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Comparing jsr166/src/jsr166e/ConcurrentHashMapV8.java (file contents):
Revision 1.47 by jsr166, Fri Jul 6 21:37:40 2012 UTC vs.
Revision 1.126 by jsr166, Mon Mar 7 23:55:31 2016 UTC

#	Line 5 | Line 5
5		*/
6
7		package jsr166e;
8	<	import jsr166e.LongAdder;
8	>
9	>	import jsr166e.ForkJoinPool;
10	>
11	>	import java.io.ObjectStreamField;
12	>	import java.io.Serializable;
13	>	import java.lang.reflect.ParameterizedType;
14	>	import java.lang.reflect.Type;
15	>	import java.util.AbstractMap;
16		import java.util.Arrays;
10	–	import java.util.Map;
11	–	import java.util.Set;
17		import java.util.Collection;
18	<	import java.util.AbstractMap;
19	<	import java.util.AbstractSet;
15	<	import java.util.AbstractCollection;
16	<	import java.util.Hashtable;
18	>	import java.util.ConcurrentModificationException;
19	>	import java.util.Enumeration;
20		import java.util.HashMap;
21	+	import java.util.Hashtable;
22		import java.util.Iterator;
23	<	import java.util.Enumeration;
20	<	import java.util.ConcurrentModificationException;
23	>	import java.util.Map;
24		import java.util.NoSuchElementException;
25	+	import java.util.Set;
26		import java.util.concurrent.ConcurrentMap;
27	<	import java.util.concurrent.ThreadLocalRandom;
27	>	import java.util.concurrent.atomic.AtomicReference;
28	>	import java.util.concurrent.atomic.AtomicInteger;
29		import java.util.concurrent.locks.LockSupport;
30	<	import java.util.concurrent.locks.AbstractQueuedSynchronizer;
26	<	import java.io.Serializable;
30	>	import java.util.concurrent.locks.ReentrantLock;
31
32		/**
33		* A hash table supporting full concurrency of retrievals and
#	Line 37 | Line 41 | import java.io.Serializable;
41		* interoperable with {@code Hashtable} in programs that rely on its
42		* thread safety but not on its synchronization details.
43		*
44	<	* <p> Retrieval operations (including {@code get}) generally do not
44	>	* <p>Retrieval operations (including {@code get}) generally do not
45		* block, so may overlap with update operations (including {@code put}
46		* and {@code remove}). Retrievals reflect the results of the most
47		* recently <em>completed</em> update operations holding upon their
48	<	* onset.  For aggregate operations such as {@code putAll} and {@code
49	<	* clear}, concurrent retrievals may reflect insertion or removal of
50	<	* only some entries.  Similarly, Iterators and Enumerations return
51	<	* elements reflecting the state of the hash table at some point at or
52	<	* since the creation of the iterator/enumeration.  They do
53	<	* <em>not</em> throw {@link ConcurrentModificationException}.
54	<	* However, iterators are designed to be used by only one thread at a
55	<	* time.  Bear in mind that the results of aggregate status methods
56	<	* including {@code size}, {@code isEmpty}, and {@code containsValue}
57	<	* are typically useful only when a map is not undergoing concurrent
58	<	* updates in other threads.  Otherwise the results of these methods
59	<	* reflect transient states that may be adequate for monitoring
60	<	* or estimation purposes, but not for program control.
48	>	* onset. (More formally, an update operation for a given key bears a
49	>	* <em>happens-before</em> relation with any (non-null) retrieval for
50	>	* that key reporting the updated value.)  For aggregate operations
51	>	* such as {@code putAll} and {@code clear}, concurrent retrievals may
52	>	* reflect insertion or removal of only some entries.  Similarly,
53	>	* Iterators and Enumerations return elements reflecting the state of
54	>	* the hash table at some point at or since the creation of the
55	>	* iterator/enumeration.  They do <em>not</em> throw {@link
56	>	* ConcurrentModificationException}.  However, iterators are designed
57	>	* to be used by only one thread at a time.  Bear in mind that the
58	>	* results of aggregate status methods including {@code size}, {@code
59	>	* isEmpty}, and {@code containsValue} are typically useful only when
60	>	* a map is not undergoing concurrent updates in other threads.
61	>	* Otherwise the results of these methods reflect transient states
62	>	* that may be adequate for monitoring or estimation purposes, but not
63	>	* for program control.
64		*
65	<	* <p> The table is dynamically expanded when there are too many
65	>	* <p>The table is dynamically expanded when there are too many
66		* collisions (i.e., keys that have distinct hash codes but fall into
67		* the same slot modulo the table size), with the expected average
68		* effect of maintaining roughly two bins per mapping (corresponding
#	Line 74 | Line 81 | import java.io.Serializable;
81		* expected {@code concurrencyLevel} as an additional hint for
82		* internal sizing.  Note that using many keys with exactly the same
83		* {@code hashCode()} is a sure way to slow down performance of any
84	<	* hash table.
84	>	* hash table. To ameliorate impact, when keys are {@link Comparable},
85	>	* this class may use comparison order among keys to help break ties.
86	>	*
87	>	* <p>A {@link Set} projection of a ConcurrentHashMapV8 may be created
88	>	* (using {@link #newKeySet()} or {@link #newKeySet(int)}), or viewed
89	>	* (using {@link #keySet(Object)} when only keys are of interest, and the
90	>	* mapped values are (perhaps transiently) not used or all take the
91	>	* same mapping value.
92		*
93		* <p>This class and its views and iterators implement all of the
94		* <em>optional</em> methods of the {@link Map} and {@link Iterator}
95		* interfaces.
96		*
97	<	* <p> Like {@link Hashtable} but unlike {@link HashMap}, this class
97	>	* <p>Like {@link Hashtable} but unlike {@link HashMap}, this class
98		* does <em>not</em> allow {@code null} to be used as a key or value.
99		*
100	+	* <p>ConcurrentHashMapV8s support a set of sequential and parallel bulk
101	+	* operations that are designed
102	+	* to be safely, and often sensibly, applied even with maps that are
103	+	* being concurrently updated by other threads; for example, when
104	+	* computing a snapshot summary of the values in a shared registry.
105	+	* There are three kinds of operation, each with four forms, accepting
106	+	* functions with Keys, Values, Entries, and (Key, Value) arguments
107	+	* and/or return values. Because the elements of a ConcurrentHashMapV8
108	+	* are not ordered in any particular way, and may be processed in
109	+	* different orders in different parallel executions, the correctness
110	+	* of supplied functions should not depend on any ordering, or on any
111	+	* other objects or values that may transiently change while
112	+	* computation is in progress; and except for forEach actions, should
113	+	* ideally be side-effect-free. Bulk operations on {@link java.util.Map.Entry}
114	+	* objects do not support method {@code setValue}.
115	+	*
116	+	* <ul>
117	+	* <li>forEach: Perform a given action on each element.
118	+	* A variant form applies a given transformation on each element
119	+	* before performing the action.
120	+	*
121	+	* <li>search: Return the first available non-null result of
122	+	* applying a given function on each element; skipping further
123	+	* search when a result is found.
124	+	*
125	+	* <li>reduce: Accumulate each element.  The supplied reduction
126	+	* function cannot rely on ordering (more formally, it should be
127	+	* both associative and commutative).  There are five variants:
128	+	*
129	+	* <ul>
130	+	*
131	+	* <li>Plain reductions. (There is not a form of this method for
132	+	* (key, value) function arguments since there is no corresponding
133	+	* return type.)
134	+	*
135	+	* <li>Mapped reductions that accumulate the results of a given
136	+	* function applied to each element.
137	+	*
138	+	* <li>Reductions to scalar doubles, longs, and ints, using a
139	+	* given basis value.
140	+	*
141	+	* </ul>
142	+	* </ul>
143	+	*
144	+	* <p>These bulk operations accept a {@code parallelismThreshold}
145	+	* argument. Methods proceed sequentially if the current map size is
146	+	* estimated to be less than the given threshold. Using a value of
147	+	* {@code Long.MAX_VALUE} suppresses all parallelism.  Using a value
148	+	* of {@code 1} results in maximal parallelism by partitioning into
149	+	* enough subtasks to fully utilize the {@link
150	+	* ForkJoinPool#commonPool()} that is used for all parallel
151	+	* computations. Normally, you would initially choose one of these
152	+	* extreme values, and then measure performance of using in-between
153	+	* values that trade off overhead versus throughput.
154	+	*
155	+	* <p>The concurrency properties of bulk operations follow
156	+	* from those of ConcurrentHashMapV8: Any non-null result returned
157	+	* from {@code get(key)} and related access methods bears a
158	+	* happens-before relation with the associated insertion or
159	+	* update.  The result of any bulk operation reflects the
160	+	* composition of these per-element relations (but is not
161	+	* necessarily atomic with respect to the map as a whole unless it
162	+	* is somehow known to be quiescent).  Conversely, because keys
163	+	* and values in the map are never null, null serves as a reliable
164	+	* atomic indicator of the current lack of any result.  To
165	+	* maintain this property, null serves as an implicit basis for
166	+	* all non-scalar reduction operations. For the double, long, and
167	+	* int versions, the basis should be one that, when combined with
168	+	* any other value, returns that other value (more formally, it
169	+	* should be the identity element for the reduction). Most common
170	+	* reductions have these properties; for example, computing a sum
171	+	* with basis 0 or a minimum with basis MAX_VALUE.
172	+	*
173	+	* <p>Search and transformation functions provided as arguments
174	+	* should similarly return null to indicate the lack of any result
175	+	* (in which case it is not used). In the case of mapped
176	+	* reductions, this also enables transformations to serve as
177	+	* filters, returning null (or, in the case of primitive
178	+	* specializations, the identity basis) if the element should not
179	+	* be combined. You can create compound transformations and
180	+	* filterings by composing them yourself under this "null means
181	+	* there is nothing there now" rule before using them in search or
182	+	* reduce operations.
183	+	*
184	+	* <p>Methods accepting and/or returning Entry arguments maintain
185	+	* key-value associations. They may be useful for example when
186	+	* finding the key for the greatest value. Note that "plain" Entry
187	+	* arguments can be supplied using {@code new
188	+	* AbstractMap.SimpleEntry(k,v)}.
189	+	*
190	+	* <p>Bulk operations may complete abruptly, throwing an
191	+	* exception encountered in the application of a supplied
192	+	* function. Bear in mind when handling such exceptions that other
193	+	* concurrently executing functions could also have thrown
194	+	* exceptions, or would have done so if the first exception had
195	+	* not occurred.
196	+	*
197	+	* <p>Speedups for parallel compared to sequential forms are common
198	+	* but not guaranteed.  Parallel operations involving brief functions
199	+	* on small maps may execute more slowly than sequential forms if the
200	+	* underlying work to parallelize the computation is more expensive
201	+	* than the computation itself.  Similarly, parallelization may not
202	+	* lead to much actual parallelism if all processors are busy
203	+	* performing unrelated tasks.
204	+	*
205	+	* <p>All arguments to all task methods must be non-null.
206	+	*
207	+	* <p><em>jsr166e note: During transition, this class
208	+	* uses nested functional interfaces with different names but the
209	+	* same forms as those expected for JDK8.</em>
210	+	*
211		* <p>This class is a member of the
212		* <a href="{@docRoot}/../technotes/guides/collections/index.html">
213		* Java Collections Framework</a>.
214		*
90	–	* <p><em>jsr166e note: This class is a candidate replacement for
91	–	* java.util.concurrent.ConcurrentHashMap.<em>
92	–	*
215		* @since 1.5
216		* @author Doug Lea
217		* @param <K> the type of keys maintained by this map
218		* @param <V> the type of mapped values
219		*/
220	<	public class ConcurrentHashMapV8<K, V>
221	<	implements ConcurrentMap<K, V>, Serializable {
220	>	public class ConcurrentHashMapV8<K,V> extends AbstractMap<K,V>
221	>	implements ConcurrentMap<K,V>, Serializable {
222		private static final long serialVersionUID = 7249069246763182397L;
223
224		/**
225	<	* A function computing a mapping from the given key to a value.
226	<	* This is a place-holder for an upcoming JDK8 interface.
225	>	* An object for traversing and partitioning elements of a source.
226	>	* This interface provides a subset of the functionality of JDK8
227	>	* java.util.Spliterator.
228		*/
229	<	public static interface MappingFunction<K, V> {
229	>	public static interface ConcurrentHashMapSpliterator<T> {
230		/**
231	<	* Returns a value for the given key, or null if there is no mapping.
232	<	*
233	<	* @param key the (non-null) key
234	<	* @return a value for the key, or null if none
231	>	* If possible, returns a new spliterator covering
232	>	* approximately one half of the elements, which will not be
233	>	* covered by this spliterator. Returns null if cannot be
234	>	* split.
235		*/
236	<	V map(K key);
114	<	}
115	<
116	<	/**
117	<	* A function computing a new mapping given a key and its current
118	<	* mapped value (or {@code null} if there is no current
119	<	* mapping). This is a place-holder for an upcoming JDK8
120	<	* interface.
121	<	*/
122	<	public static interface RemappingFunction<K, V> {
236	>	ConcurrentHashMapSpliterator<T> trySplit();
237		/**
238	<	* Returns a new value given a key and its current value.
239	<	*
126	<	* @param key the (non-null) key
127	<	* @param value the current value, or null if there is no mapping
128	<	* @return a value for the key, or null if none
129	<	*/
130	<	V remap(K key, V value);
131	<	}
132	<
133	<	/**
134	<	* A partitionable iterator. A Spliterator can be traversed
135	<	* directly, but can also be partitioned (before traversal) by
136	<	* creating another Spliterator that covers a non-overlapping
137	<	* portion of the elements, and so may be amenable to parallel
138	<	* execution.
139	<	*
140	<	* <p> This interface exports a subset of expected JDK8
141	<	* functionality.
142	<	*
143	<	* <p>Sample usage: Here is one (of the several) ways to compute
144	<	* the sum of the values held in a map using the ForkJoin
145	<	* framework. As illustrated here, Spliterators are well suited to
146	<	* designs in which a task repeatedly splits off half its work
147	<	* into forked subtasks until small enough to process directly,
148	<	* and then joins these subtasks. Variants of this style can also
149	<	* be used in completion-based designs.
150	<	*
151	<	* <pre>
152	<	* {@code ConcurrentHashMapV8<String, Long> m = ...
153	<	* // Uses parallel depth of log2 of size / (parallelism * slack of 8).
154	<	* int depth = 32 - Integer.numberOfLeadingZeros(m.size() / (aForkJoinPool.getParallelism() * 8));
155	<	* long sum = aForkJoinPool.invoke(new SumValues(m.valueSpliterator(), depth, null));
156	<	* // ...
157	<	* static class SumValues extends RecursiveTask<Long> {
158	<	*   final Spliterator<Long> s;
159	<	*   final int depth;             // number of splits before processing
160	<	*   final SumValues nextJoin;    // records forked subtasks to join
161	<	*   SumValues(Spliterator<Long> s, int depth, SumValues nextJoin) {
162	<	*     this.s = s; this.depth = depth; this.nextJoin = nextJoin;
163	<	*   }
164	<	*   public Long compute() {
165	<	*     long sum = 0;
166	<	*     SumValues subtasks = null; // fork subtasks
167	<	*     for (int d = depth - 1; d >= 0; --d)
168	<	*       (subtasks = new SumValues(s.split(), d, subtasks)).fork();
169	<	*     while (s.hasNext())        // directly process remaining elements
170	<	*       sum += s.next();
171	<	*     for (SumValues t = subtasks; t != null; t = t.nextJoin)
172	<	*       sum += t.join();         // collect subtask results
173	<	*     return sum;
174	<	*   }
175	<	* }
176	<	* }</pre>
177	<	*/
178	<	public static interface Spliterator<T> extends Iterator<T> {
179	<	/**
180	<	* Returns a Spliterator covering approximately half of the
181	<	* elements, guaranteed not to overlap with those subsequently
182	<	* returned by this Spliterator.  After invoking this method,
183	<	* the current Spliterator will <em>not</em> produce any of
184	<	* the elements of the returned Spliterator, but the two
185	<	* Spliterators together will produce all of the elements that
186	<	* would have been produced by this Spliterator had this
187	<	* method not been called. The exact number of elements
188	<	* produced by the returned Spliterator is not guaranteed, and
189	<	* may be zero (i.e., with {@code hasNext()} reporting {@code
190	<	* false}) if this Spliterator cannot be further split.
191	<	*
192	<	* @return a Spliterator covering approximately half of the
193	<	* elements
194	<	* @throws IllegalStateException if this Spliterator has
195	<	* already commenced traversing elements
238	>	* Returns an estimate of the number of elements covered by
239	>	* this Spliterator.
240		*/
241	<	Spliterator<T> split();
242	<	}
241	>	long estimateSize();
242	>
243	>	/** Applies the action to each untraversed element */
244	>	void forEachRemaining(Action<? super T> action);
245	>	/** If an element remains, applies the action and returns true. */
246	>	boolean tryAdvance(Action<? super T> action);
247	>	}
248	>
249	>	// Sams
250	>	/** Interface describing a void action of one argument */
251	>	public interface Action<A> { void apply(A a); }
252	>	/** Interface describing a void action of two arguments */
253	>	public interface BiAction<A,B> { void apply(A a, B b); }
254	>	/** Interface describing a function of one argument */
255	>	public interface Fun<A,T> { T apply(A a); }
256	>	/** Interface describing a function of two arguments */
257	>	public interface BiFun<A,B,T> { T apply(A a, B b); }
258	>	/** Interface describing a function mapping its argument to a double */
259	>	public interface ObjectToDouble<A> { double apply(A a); }
260	>	/** Interface describing a function mapping its argument to a long */
261	>	public interface ObjectToLong<A> { long apply(A a); }
262	>	/** Interface describing a function mapping its argument to an int */
263	>	public interface ObjectToInt<A> {int apply(A a); }
264	>	/** Interface describing a function mapping two arguments to a double */
265	>	public interface ObjectByObjectToDouble<A,B> { double apply(A a, B b); }
266	>	/** Interface describing a function mapping two arguments to a long */
267	>	public interface ObjectByObjectToLong<A,B> { long apply(A a, B b); }
268	>	/** Interface describing a function mapping two arguments to an int */
269	>	public interface ObjectByObjectToInt<A,B> {int apply(A a, B b); }
270	>	/** Interface describing a function mapping two doubles to a double */
271	>	public interface DoubleByDoubleToDouble { double apply(double a, double b); }
272	>	/** Interface describing a function mapping two longs to a long */
273	>	public interface LongByLongToLong { long apply(long a, long b); }
274	>	/** Interface describing a function mapping two ints to an int */
275	>	public interface IntByIntToInt { int apply(int a, int b); }
276	>
277
278		/*
279		* Overview:
#	Line 207 | Line 285 | public class ConcurrentHashMapV8<K, V>
285		* the same or better than java.util.HashMap, and to support high
286		* initial insertion rates on an empty table by many threads.
287		*
288	<	* Each key-value mapping is held in a Node.  Because Node fields
289	<	* can contain special values, they are defined using plain Object
290	<	* types. Similarly in turn, all internal methods that use them
291	<	* work off Object types. And similarly, so do the internal
292	<	* methods of auxiliary iterator and view classes.  All public
293	<	* generic typed methods relay in/out of these internal methods,
294	<	* supplying null-checks and casts as needed. This also allows
295	<	* many of the public methods to be factored into a smaller number
296	<	* of internal methods (although sadly not so for the five
297	<	* variants of put-related operations). The validation-based
298	<	* approach explained below leads to a lot of code sprawl because
299	<	* retry-control precludes factoring into smaller methods.
288	>	* This map usually acts as a binned (bucketed) hash table.  Each
289	>	* key-value mapping is held in a Node.  Most nodes are instances
290	>	* of the basic Node class with hash, key, value, and next
291	>	* fields. However, various subclasses exist: TreeNodes are
292	>	* arranged in balanced trees, not lists.  TreeBins hold the roots
293	>	* of sets of TreeNodes. ForwardingNodes are placed at the heads
294	>	* of bins during resizing. ReservationNodes are used as
295	>	* placeholders while establishing values in computeIfAbsent and
296	>	* related methods.  The types TreeBin, ForwardingNode, and
297	>	* ReservationNode do not hold normal user keys, values, or
298	>	* hashes, and are readily distinguishable during search etc
299	>	* because they have negative hash fields and null key and value
300	>	* fields. (These special nodes are either uncommon or transient,
301	>	* so the impact of carrying around some unused fields is
302	>	* insignificant.)
303		*
304		* The table is lazily initialized to a power-of-two size upon the
305		* first insertion.  Each bin in the table normally contains a
#	Line 226 | Line 307 | public class ConcurrentHashMapV8<K, V>
307		* Table accesses require volatile/atomic reads, writes, and
308		* CASes.  Because there is no other way to arrange this without
309		* adding further indirections, we use intrinsics
310	<	* (sun.misc.Unsafe) operations.  The lists of nodes within bins
311	<	* are always accurately traversable under volatile reads, so long
312	<	* as lookups check hash code and non-nullness of value before
313	<	* checking key equality.
314	<	*
315	<	* We use the top two bits of Node hash fields for control
235	<	* purposes -- they are available anyway because of addressing
236	<	* constraints.  As explained further below, these top bits are
237	<	* used as follows:
238	<	*  00 - Normal
239	<	*  01 - Locked
240	<	*  11 - Locked and may have a thread waiting for lock
241	<	*  10 - Node is a forwarding node
242	<	*
243	<	* The lower 30 bits of each Node's hash field contain a
244	<	* transformation of the key's hash code, except for forwarding
245	<	* nodes, for which the lower bits are zero (and so always have
246	<	* hash field == MOVED).
310	>	* (sun.misc.Unsafe) operations.
311	>	*
312	>	* We use the top (sign) bit of Node hash fields for control
313	>	* purposes -- it is available anyway because of addressing
314	>	* constraints.  Nodes with negative hash fields are specially
315	>	* handled or ignored in map methods.
316		*
317		* Insertion (via put or its variants) of the first node in an
318		* empty bin is performed by just CASing it to the bin.  This is
#	Line 252 | Line 321 | public class ConcurrentHashMapV8<K, V>
321		* delete, and replace) require locks.  We do not want to waste
322		* the space required to associate a distinct lock object with
323		* each bin, so instead use the first node of a bin list itself as
324	<	* a lock. Blocking support for these locks relies on the builtin
325	<	* "synchronized" monitors.  However, we also need a tryLock
257	<	* construction, so we overlay these by using bits of the Node
258	<	* hash field for lock control (see above), and so normally use
259	<	* builtin monitors only for blocking and signalling using
260	<	* wait/notifyAll constructions. See Node.tryAwaitLock.
324	>	* a lock. Locking support for these locks relies on builtin
325	>	* "synchronized" monitors.
326		*
327		* Using the first node of a list as a lock does not by itself
328		* suffice though: When a node is locked, any update must first
329		* validate that it is still the first node after locking it, and
330		* retry if not. Because new nodes are always appended to lists,
331		* once a node is first in a bin, it remains first until deleted
332	<	* or the bin becomes invalidated (upon resizing).  However,
268	<	* operations that only conditionally update may inspect nodes
269	<	* until the point of update. This is a converse of sorts to the
270	<	* lazy locking technique described by Herlihy & Shavit.
332	>	* or the bin becomes invalidated (upon resizing).
333		*
334		* The main disadvantage of per-bin locks is that other update
335		* operations on other nodes in a bin list protected by the same
#	Line 300 | Line 362 | public class ConcurrentHashMapV8<K, V>
362		* sometimes deviate significantly from uniform randomness.  This
363		* includes the case when N > (1<<30), so some keys MUST collide.
364		* Similarly for dumb or hostile usages in which multiple keys are
365	<	* designed to have identical hash codes. Also, although we guard
366	<	* against the worst effects of this (see method spread), sets of
367	<	* hashes may differ only in bits that do not impact their bin
368	<	* index for a given power-of-two mask.  So we use a secondary
369	<	* strategy that applies when the number of nodes in a bin exceeds
370	<	* a threshold, and at least one of the keys implements
309	<	* Comparable.  These TreeBins use a balanced tree to hold nodes
310	<	* (a specialized form of red-black trees), bounding search time
311	<	* to O(log N).  Each search step in a TreeBin is around twice as
365	>	* designed to have identical hash codes or ones that differs only
366	>	* in masked-out high bits. So we use a secondary strategy that
367	>	* applies when the number of nodes in a bin exceeds a
368	>	* threshold. These TreeBins use a balanced tree to hold nodes (a
369	>	* specialized form of red-black trees), bounding search time to
370	>	* O(log N).  Each search step in a TreeBin is at least twice as
371		* slow as in a regular list, but given that N cannot exceed
372		* (1<<64) (before running out of addresses) this bounds search
373		* steps, lock hold times, etc, to reasonable constants (roughly
#	Line 319 | Line 378 | public class ConcurrentHashMapV8<K, V>
378		* iterators in the same way.
379		*
380		* The table is resized when occupancy exceeds a percentage
381	<	* threshold (nominally, 0.75, but see below).  Only a single
382	<	* thread performs the resize (using field "sizeCtl", to arrange
383	<	* exclusion), but the table otherwise remains usable for reads
384	<	* and updates. Resizing proceeds by transferring bins, one by
385	<	* one, from the table to the next table.  Because we are using
386	<	* power-of-two expansion, the elements from each bin must either
387	<	* stay at same index, or move with a power of two offset. We
388	<	* eliminate unnecessary node creation by catching cases where old
389	<	* nodes can be reused because their next fields won't change.  On
390	<	* average, only about one-sixth of them need cloning when a table
391	<	* doubles. The nodes they replace will be garbage collectable as
392	<	* soon as they are no longer referenced by any reader thread that
393	<	* may be in the midst of concurrently traversing table.  Upon
394	<	* transfer, the old table bin contains only a special forwarding
395	<	* node (with hash field "MOVED") that contains the next table as
396	<	* its key. On encountering a forwarding node, access and update
397	<	* operations restart, using the new table.
398	<	*
399	<	* Each bin transfer requires its bin lock. However, unlike other
400	<	* cases, a transfer can skip a bin if it fails to acquire its
401	<	* lock, and revisit it later (unless it is a TreeBin). Method
402	<	* rebuild maintains a buffer of TRANSFER_BUFFER_SIZE bins that
403	<	* have been skipped because of failure to acquire a lock, and
404	<	* blocks only if none are available (i.e., only very rarely).
405	<	* The transfer operation must also ensure that all accessible
406	<	* bins in both the old and new table are usable by any traversal.
407	<	* When there are no lock acquisition failures, this is arranged
408	<	* simply by proceeding from the last bin (table.length - 1) up
409	<	* towards the first.  Upon seeing a forwarding node, traversals
410	<	* (see class InternalIterator) arrange to move to the new table
411	<	* without revisiting nodes.  However, when any node is skipped
412	<	* during a transfer, all earlier table bins may have become
413	<	* visible, so are initialized with a reverse-forwarding node back
414	<	* to the old table until the new ones are established. (This
415	<	* sometimes requires transiently locking a forwarding node, which
416	<	* is possible under the above encoding.) These more expensive
417	<	* mechanics trigger only when necessary.
381	>	* threshold (nominally, 0.75, but see below).  Any thread
382	>	* noticing an overfull bin may assist in resizing after the
383	>	* initiating thread allocates and sets up the replacement array.
384	>	* However, rather than stalling, these other threads may proceed
385	>	* with insertions etc.  The use of TreeBins shields us from the
386	>	* worst case effects of overfilling while resizes are in
387	>	* progress.  Resizing proceeds by transferring bins, one by one,
388	>	* from the table to the next table. However, threads claim small
389	>	* blocks of indices to transfer (via field transferIndex) before
390	>	* doing so, reducing contention.  A generation stamp in field
391	>	* sizeCtl ensures that resizings do not overlap. Because we are
392	>	* using power-of-two expansion, the elements from each bin must
393	>	* either stay at same index, or move with a power of two
394	>	* offset. We eliminate unnecessary node creation by catching
395	>	* cases where old nodes can be reused because their next fields
396	>	* won't change.  On average, only about one-sixth of them need
397	>	* cloning when a table doubles. The nodes they replace will be
398	>	* garbage collectable as soon as they are no longer referenced by
399	>	* any reader thread that may be in the midst of concurrently
400	>	* traversing table.  Upon transfer, the old table bin contains
401	>	* only a special forwarding node (with hash field "MOVED") that
402	>	* contains the next table as its key. On encountering a
403	>	* forwarding node, access and update operations restart, using
404	>	* the new table.
405	>	*
406	>	* Each bin transfer requires its bin lock, which can stall
407	>	* waiting for locks while resizing. However, because other
408	>	* threads can join in and help resize rather than contend for
409	>	* locks, average aggregate waits become shorter as resizing
410	>	* progresses.  The transfer operation must also ensure that all
411	>	* accessible bins in both the old and new table are usable by any
412	>	* traversal.  This is arranged in part by proceeding from the
413	>	* last bin (table.length - 1) up towards the first.  Upon seeing
414	>	* a forwarding node, traversals (see class Traverser) arrange to
415	>	* move to the new table without revisiting nodes.  To ensure that
416	>	* no intervening nodes are skipped even when moved out of order,
417	>	* a stack (see class TableStack) is created on first encounter of
418	>	* a forwarding node during a traversal, to maintain its place if
419	>	* later processing the current table. The need for these
420	>	* save/restore mechanics is relatively rare, but when one
421	>	* forwarding node is encountered, typically many more will be.
422	>	* So Traversers use a simple caching scheme to avoid creating so
423	>	* many new TableStack nodes. (Thanks to Peter Levart for
424	>	* suggesting use of a stack here.)
425		*
426		* The traversal scheme also applies to partial traversals of
427	<	* ranges of bins (via an alternate InternalIterator constructor)
427	>	* ranges of bins (via an alternate Traverser constructor)
428		* to support partitioned aggregate operations.  Also, read-only
429		* operations give up if ever forwarded to a null table, which
430		* provides support for shutdown-style clearing, which is also not
#	Line 370 | Line 436 | public class ConcurrentHashMapV8<K, V>
436		* These cases attempt to override the initial capacity settings,
437		* but harmlessly fail to take effect in cases of races.
438		*
439	<	* The element count is maintained using a LongAdder, which avoids
440	<	* contention on updates but can encounter cache thrashing if read
441	<	* too frequently during concurrent access. To avoid reading so
442	<	* often, resizing is attempted either when a bin lock is
443	<	* contended, or upon adding to a bin already holding two or more
444	<	* nodes (checked before adding in the xIfAbsent methods, after
445	<	* adding in others). Under uniform hash distributions, the
446	<	* probability of this occurring at threshold is around 13%,
447	<	* meaning that only about 1 in 8 puts check threshold (and after
448	<	* resizing, many fewer do so). But this approximation has high
449	<	* variance for small table sizes, so we check on any collision
450	<	* for sizes <= 64. The bulk putAll operation further reduces
451	<	* contention by only committing count updates upon these size
452	<	* checks.
439	>	* The element count is maintained using a specialization of
440	>	* LongAdder. We need to incorporate a specialization rather than
441	>	* just use a LongAdder in order to access implicit
442	>	* contention-sensing that leads to creation of multiple
443	>	* CounterCells.  The counter mechanics avoid contention on
444	>	* updates but can encounter cache thrashing if read too
445	>	* frequently during concurrent access. To avoid reading so often,
446	>	* resizing under contention is attempted only upon adding to a
447	>	* bin already holding two or more nodes. Under uniform hash
448	>	* distributions, the probability of this occurring at threshold
449	>	* is around 13%, meaning that only about 1 in 8 puts check
450	>	* threshold (and after resizing, many fewer do so).
451	>	*
452	>	* TreeBins use a special form of comparison for search and
453	>	* related operations (which is the main reason we cannot use
454	>	* existing collections such as TreeMaps). TreeBins contain
455	>	* Comparable elements, but may contain others, as well as
456	>	* elements that are Comparable but not necessarily Comparable for
457	>	* the same T, so we cannot invoke compareTo among them. To handle
458	>	* this, the tree is ordered primarily by hash value, then by
459	>	* Comparable.compareTo order if applicable.  On lookup at a node,
460	>	* if elements are not comparable or compare as 0 then both left
461	>	* and right children may need to be searched in the case of tied
462	>	* hash values. (This corresponds to the full list search that
463	>	* would be necessary if all elements were non-Comparable and had
464	>	* tied hashes.) On insertion, to keep a total ordering (or as
465	>	* close as is required here) across rebalancings, we compare
466	>	* classes and identityHashCodes as tie-breakers. The red-black
467	>	* balancing code is updated from pre-jdk-collections
468	>	* (http://gee.cs.oswego.edu/dl/classes/collections/RBCell.java)
469	>	* based in turn on Cormen, Leiserson, and Rivest "Introduction to
470	>	* Algorithms" (CLR).
471	>	*
472	>	* TreeBins also require an additional locking mechanism.  While
473	>	* list traversal is always possible by readers even during
474	>	* updates, tree traversal is not, mainly because of tree-rotations
475	>	* that may change the root node and/or its linkages.  TreeBins
476	>	* include a simple read-write lock mechanism parasitic on the
477	>	* main bin-synchronization strategy: Structural adjustments
478	>	* associated with an insertion or removal are already bin-locked
479	>	* (and so cannot conflict with other writers) but must wait for
480	>	* ongoing readers to finish. Since there can be only one such
481	>	* waiter, we use a simple scheme using a single "waiter" field to
482	>	* block writers.  However, readers need never block.  If the root
483	>	* lock is held, they proceed along the slow traversal path (via
484	>	* next-pointers) until the lock becomes available or the list is
485	>	* exhausted, whichever comes first. These cases are not fast, but
486	>	* maximize aggregate expected throughput.
487		*
488		* Maintaining API and serialization compatibility with previous
489		* versions of this class introduces several oddities. Mainly: We
490	<	* leave untouched but unused constructor arguments refering to
490	>	* leave untouched but unused constructor arguments referring to
491		* concurrencyLevel. We accept a loadFactor constructor argument,
492		* but apply it only to initial table capacity (which is the only
493		* time that we can guarantee to honor it.) We also declare an
494		* unused "Segment" class that is instantiated in minimal form
495		* only when serializing.
496	+	*
497	+	* Also, solely for compatibility with previous versions of this
498	+	* class, it extends AbstractMap, even though all of its methods
499	+	* are overridden, so it is just useless baggage.
500	+	*
501	+	* This file is organized to make things a little easier to follow
502	+	* while reading than they might otherwise: First the main static
503	+	* declarations and utilities, then fields, then main public
504	+	* methods (with a few factorings of multiple public methods into
505	+	* internal ones), then sizing methods, trees, traversers, and
506	+	* bulk operations.
507		*/
508
509		/* ---------------- Constants -------------- */
#	Line 434 | Line 545 | public class ConcurrentHashMapV8<K, V>
545		private static final float LOAD_FACTOR = 0.75f;
546
547		/**
548	<	* The buffer size for skipped bins during transfers. The
549	<	* value is arbitrary but should be large enough to avoid
550	<	* most locking stalls during resizes.
548	>	* The bin count threshold for using a tree rather than list for a
549	>	* bin.  Bins are converted to trees when adding an element to a
550	>	* bin with at least this many nodes. The value must be greater
551	>	* than 2, and should be at least 8 to mesh with assumptions in
552	>	* tree removal about conversion back to plain bins upon
553	>	* shrinkage.
554		*/
555	<	private static final int TRANSFER_BUFFER_SIZE = 32;
555	>	static final int TREEIFY_THRESHOLD = 8;
556
557		/**
558	<	* The bin count threshold for using a tree rather than list for a
559	<	* bin.  The value reflects the approximate break-even point for
560	<	* using tree-based operations.
558	>	* The bin count threshold for untreeifying a (split) bin during a
559	>	* resize operation. Should be less than TREEIFY_THRESHOLD, and at
560	>	* most 6 to mesh with shrinkage detection under removal.
561		*/
562	<	private static final int TREE_THRESHOLD = 8;
562	>	static final int UNTREEIFY_THRESHOLD = 6;
563
564	<	/*
565	<	* Encodings for special uses of Node hash fields. See above for
566	<	* explanation.
564	>	/**
565	>	* The smallest table capacity for which bins may be treeified.
566	>	* (Otherwise the table is resized if too many nodes in a bin.)
567	>	* The value should be at least 4 * TREEIFY_THRESHOLD to avoid
568	>	* conflicts between resizing and treeification thresholds.
569		*/
570	<	static final int MOVED     = 0x80000000; // hash field for forwarding nodes
455	<	static final int LOCKED    = 0x40000000; // set/tested only as a bit
456	<	static final int WAITING   = 0xc0000000; // both bits set/tested together
457	<	static final int HASH_BITS = 0x3fffffff; // usable bits of normal node hash
458	<
459	<	/* ---------------- Fields -------------- */
570	>	static final int MIN_TREEIFY_CAPACITY = 64;
571
572		/**
573	<	* The array of bins. Lazily initialized upon first insertion.
574	<	* Size is always a power of two. Accessed directly by iterators.
573	>	* Minimum number of rebinnings per transfer step. Ranges are
574	>	* subdivided to allow multiple resizer threads.  This value
575	>	* serves as a lower bound to avoid resizers encountering
576	>	* excessive memory contention.  The value should be at least
577	>	* DEFAULT_CAPACITY.
578		*/
579	<	transient volatile Node[] table;
579	>	private static final int MIN_TRANSFER_STRIDE = 16;
580
581		/**
582	<	* The counter maintaining number of elements.
582	>	* The number of bits used for generation stamp in sizeCtl.
583	>	* Must be at least 6 for 32bit arrays.
584		*/
585	<	private transient final LongAdder counter;
585	>	private static int RESIZE_STAMP_BITS = 16;
586
587		/**
588	<	* Table initialization and resizing control.  When negative, the
589	<	* table is being initialized or resized. Otherwise, when table is
475	<	* null, holds the initial table size to use upon creation, or 0
476	<	* for default. After initialization, holds the next element count
477	<	* value upon which to resize the table.
588	>	* The maximum number of threads that can help resize.
589	>	* Must fit in 32 - RESIZE_STAMP_BITS bits.
590		*/
591	<	private transient volatile int sizeCtl;
591	>	private static final int MAX_RESIZERS = (1 << (32 - RESIZE_STAMP_BITS)) - 1;
592
593	<	// views
594	<	private transient KeySet<K,V> keySet;
595	<	private transient Values<K,V> values;
596	<	private transient EntrySet<K,V> entrySet;
485	<
486	<	/** For serialization compatibility. Null unless serialized; see below */
487	<	private Segment<K,V>[] segments;
488	<
489	<	/* ---------------- Table element access -------------- */
593	>	/**
594	>	* The bit shift for recording size stamp in sizeCtl.
595	>	*/
596	>	private static final int RESIZE_STAMP_SHIFT = 32 - RESIZE_STAMP_BITS;
597
598		/*
599	<	* Volatile access methods are used for table elements as well as
493	<	* elements of in-progress next table while resizing.  Uses are
494	<	* null checked by callers, and implicitly bounds-checked, relying
495	<	* on the invariants that tab arrays have non-zero size, and all
496	<	* indices are masked with (tab.length - 1) which is never
497	<	* negative and always less than length. Note that, to be correct
498	<	* wrt arbitrary concurrency errors by users, bounds checks must
499	<	* operate on local variables, which accounts for some odd-looking
500	<	* inline assignments below.
599	>	* Encodings for Node hash fields. See above for explanation.
600		*/
601	<
602	<	static final Node tabAt(Node[] tab, int i) { // used by InternalIterator
603	<	return (Node)UNSAFE.getObjectVolatile(tab, ((long)i<<ASHIFT)+ABASE);
604	<	}
605	<
606	<	private static final boolean casTabAt(Node[] tab, int i, Node c, Node v) {
607	<	return UNSAFE.compareAndSwapObject(tab, ((long)i<<ASHIFT)+ABASE, c, v);
608	<	}
609	<
610	<	private static final void setTabAt(Node[] tab, int i, Node v) {
611	<	UNSAFE.putObjectVolatile(tab, ((long)i<<ASHIFT)+ABASE, v);
612	<	}
601	>	static final int MOVED     = -1; // hash for forwarding nodes
602	>	static final int TREEBIN   = -2; // hash for roots of trees
603	>	static final int RESERVED  = -3; // hash for transient reservations
604	>	static final int HASH_BITS = 0x7fffffff; // usable bits of normal node hash
605	>
606	>	/** Number of CPUS, to place bounds on some sizings */
607	>	static final int NCPU = Runtime.getRuntime().availableProcessors();
608	>
609	>	/** For serialization compatibility. */
610	>	private static final ObjectStreamField[] serialPersistentFields = {
611	>	new ObjectStreamField("segments", Segment[].class),
612	>	new ObjectStreamField("segmentMask", Integer.TYPE),
613	>	new ObjectStreamField("segmentShift", Integer.TYPE)
614	>	};
615
616		/* ---------------- Nodes -------------- */
617
618		/**
619	<	* Key-value entry. Note that this is never exported out as a
620	<	* user-visible Map.Entry (see MapEntry below). Nodes with a hash
621	<	* field of MOVED are special, and do not contain user keys or
622	<	* values.  Otherwise, keys are never null, and null val fields
623	<	* indicate that a node is in the process of being deleted or
624	<	* created. For purposes of read-only access, a key may be read
625	<	* before a val, but can only be used after checking val to be
626	<	* non-null.
627	<	*/
628	<	static class Node {
629	<	volatile int hash;
630	<	final Object key;
530	<	volatile Object val;
531	<	volatile Node next;
619	>	* Key-value entry.  This class is never exported out as a
620	>	* user-mutable Map.Entry (i.e., one supporting setValue; see
621	>	* MapEntry below), but can be used for read-only traversals used
622	>	* in bulk tasks.  Subclasses of Node with a negative hash field
623	>	* are special, and contain null keys and values (but are never
624	>	* exported).  Otherwise, keys and vals are never null.
625	>	*/
626	>	static class Node<K,V> implements Map.Entry<K,V> {
627	>	final int hash;
628	>	final K key;
629	>	volatile V val;
630	>	volatile Node<K,V> next;
631
632	<	Node(int hash, Object key, Object val, Node next) {
632	>	Node(int hash, K key, V val, Node<K,V> next) {
633		this.hash = hash;
634		this.key = key;
635		this.val = val;
636		this.next = next;
637		}
638
639	<	/** CompareAndSet the hash field */
640	<	final boolean casHash(int cmp, int val) {
641	<	return UNSAFE.compareAndSwapInt(this, hashOffset, cmp, val);
642	<	}
643	<
644	<	/** The number of spins before blocking for a lock */
546	<	static final int MAX_SPINS =
547	<	Runtime.getRuntime().availableProcessors() > 1 ? 64 : 1;
548	<
549	<	/**
550	<	* Spins a while if LOCKED bit set and this node is the first
551	<	* of its bin, and then sets WAITING bits on hash field and
552	<	* blocks (once) if they are still set.  It is OK for this
553	<	* method to return even if lock is not available upon exit,
554	<	* which enables these simple single-wait mechanics.
555	<	*
556	<	* The corresponding signalling operation is performed within
557	<	* callers: Upon detecting that WAITING has been set when
558	<	* unlocking lock (via a failed CAS from non-waiting LOCKED
559	<	* state), unlockers acquire the sync lock and perform a
560	<	* notifyAll.
561	<	*/
562	<	final void tryAwaitLock(Node[] tab, int i) {
563	<	if (tab != null && i >= 0 && i < tab.length) { // bounds check
564	<	int r = ThreadLocalRandom.current().nextInt(); // randomize spins
565	<	int spins = MAX_SPINS, h;
566	<	while (tabAt(tab, i) == this && ((h = hash) & LOCKED) != 0) {
567	<	if (spins >= 0) {
568	<	r ^= r << 1; r ^= r >>> 3; r ^= r << 10; // xorshift
569	<	if (r >= 0 && --spins == 0)
570	<	Thread.yield();  // yield before block
571	<	}
572	<	else if (casHash(h, h | WAITING)) {
573	<	synchronized (this) {
574	<	if (tabAt(tab, i) == this &&
575	<	(hash & WAITING) == WAITING) {
576	<	try {
577	<	wait();
578	<	} catch (InterruptedException ie) {
579	<	Thread.currentThread().interrupt();
580	<	}
581	<	}
582	<	else
583	<	notifyAll(); // possibly won race vs signaller
584	<	}
585	<	break;
586	<	}
587	<	}
588	<	}
589	<	}
590	<
591	<	// Unsafe mechanics for casHash
592	<	private static final sun.misc.Unsafe UNSAFE;
593	<	private static final long hashOffset;
594	<
595	<	static {
596	<	try {
597	<	UNSAFE = getUnsafe();
598	<	Class<?> k = Node.class;
599	<	hashOffset = UNSAFE.objectFieldOffset
600	<	(k.getDeclaredField("hash"));
601	<	} catch (Exception e) {
602	<	throw new Error(e);
603	<	}
604	<	}
605	<	}
606	<
607	<	/* ---------------- TreeBins -------------- */
608	<
609	<	/**
610	<	* Nodes for use in TreeBins
611	<	*/
612	<	static final class TreeNode extends Node {
613	<	TreeNode parent;  // red-black tree links
614	<	TreeNode left;
615	<	TreeNode right;
616	<	TreeNode prev;    // needed to unlink next upon deletion
617	<	boolean red;
618	<
619	<	TreeNode(int hash, Object key, Object val, Node next, TreeNode parent) {
620	<	super(hash, key, val, next);
621	<	this.parent = parent;
622	<	}
623	<	}
624	<
625	<	/**
626	<	* A specialized form of red-black tree for use in bins
627	<	* whose size exceeds a threshold.
628	<	*
629	<	* TreeBins use a special form of comparison for search and
630	<	* related operations (which is the main reason we cannot use
631	<	* existing collections such as TreeMaps). TreeBins contain
632	<	* Comparable elements, but may contain others, as well as
633	<	* elements that are Comparable but not necessarily Comparable<T>
634	<	* for the same T, so we cannot invoke compareTo among them. To
635	<	* handle this, the tree is ordered primarily by hash value, then
636	<	* by getClass().getName() order, and then by Comparator order
637	<	* among elements of the same class.  On lookup at a node, if
638	<	* elements are not comparable or compare as 0, both left and
639	<	* right children may need to be searched in the case of tied hash
640	<	* values. (This corresponds to the full list search that would be
641	<	* necessary if all elements were non-Comparable and had tied
642	<	* hashes.)  The red-black balancing code is updated from
643	<	* pre-jdk-collections
644	<	* (http://gee.cs.oswego.edu/dl/classes/collections/RBCell.java)
645	<	* based in turn on Cormen, Leiserson, and Rivest "Introduction to
646	<	* Algorithms" (CLR).
647	<	*
648	<	* TreeBins also maintain a separate locking discipline than
649	<	* regular bins. Because they are forwarded via special MOVED
650	<	* nodes at bin heads (which can never change once established),
651	<	* we cannot use use those nodes as locks. Instead, TreeBin
652	<	* extends AbstractQueuedSynchronizer to support a simple form of
653	<	* read-write lock. For update operations and table validation,
654	<	* the exclusive form of lock behaves in the same way as bin-head
655	<	* locks. However, lookups use shared read-lock mechanics to allow
656	<	* multiple readers in the absence of writers.  Additionally,
657	<	* these lookups do not ever block: While the lock is not
658	<	* available, they proceed along the slow traversal path (via
659	<	* next-pointers) until the lock becomes available or the list is
660	<	* exhausted, whichever comes first. (These cases are not fast,
661	<	* but maximize aggregate expected throughput.)  The AQS mechanics
662	<	* for doing this are straightforward.  The lock state is held as
663	<	* AQS getState().  Read counts are negative; the write count (1)
664	<	* is positive.  There are no signalling preferences among readers
665	<	* and writers. Since we don't need to export full Lock API, we
666	<	* just override the minimal AQS methods and use them directly.
667	<	*/
668	<	static final class TreeBin extends AbstractQueuedSynchronizer {
669	<	private static final long serialVersionUID = 2249069246763182397L;
670	<	transient TreeNode root;  // root of tree
671	<	transient TreeNode first; // head of next-pointer list
672	<
673	<	/* AQS overrides */
674	<	public final boolean isHeldExclusively() { return getState() > 0; }
675	<	public final boolean tryAcquire(int ignore) {
676	<	if (compareAndSetState(0, 1)) {
677	<	setExclusiveOwnerThread(Thread.currentThread());
678	<	return true;
679	<	}
680	<	return false;
681	<	}
682	<	public final boolean tryRelease(int ignore) {
683	<	setExclusiveOwnerThread(null);
684	<	setState(0);
685	<	return true;
686	<	}
687	<	public final int tryAcquireShared(int ignore) {
688	<	for (int c;;) {
689	<	if ((c = getState()) > 0)
690	<	return -1;
691	<	if (compareAndSetState(c, c -1))
692	<	return 1;
693	<	}
694	<	}
695	<	public final boolean tryReleaseShared(int ignore) {
696	<	int c;
697	<	do {} while (!compareAndSetState(c = getState(), c + 1));
698	<	return c == -1;
699	<	}
700	<
701	<	/** From CLR */
702	<	private void rotateLeft(TreeNode p) {
703	<	if (p != null) {
704	<	TreeNode r = p.right, pp, rl;
705	<	if ((rl = p.right = r.left) != null)
706	<	rl.parent = p;
707	<	if ((pp = r.parent = p.parent) == null)
708	<	root = r;
709	<	else if (pp.left == p)
710	<	pp.left = r;
711	<	else
712	<	pp.right = r;
713	<	r.left = p;
714	<	p.parent = r;
715	<	}
716	<	}
717	<
718	<	/** From CLR */
719	<	private void rotateRight(TreeNode p) {
720	<	if (p != null) {
721	<	TreeNode l = p.left, pp, lr;
722	<	if ((lr = p.left = l.right) != null)
723	<	lr.parent = p;
724	<	if ((pp = l.parent = p.parent) == null)
725	<	root = l;
726	<	else if (pp.right == p)
727	<	pp.right = l;
728	<	else
729	<	pp.left = l;
730	<	l.right = p;
731	<	p.parent = l;
732	<	}
733	<	}
734	<
735	<	/**
736	<	* Return the TreeNode (or null if not found) for the given key
737	<	* starting at given root.
738	<	*/
739	<	@SuppressWarnings("unchecked") // suppress Comparable cast warning
740	<	final TreeNode getTreeNode(int h, Object k, TreeNode p) {
741	<	Class<?> c = k.getClass();
742	<	while (p != null) {
743	<	int dir, ph;  Object pk; Class<?> pc;
744	<	if ((ph = p.hash) == h) {
745	<	if ((pk = p.key) == k || k.equals(pk))
746	<	return p;
747	<	if (c != (pc = pk.getClass()) ||
748	<	!(k instanceof Comparable) ||
749	<	(dir = ((Comparable)k).compareTo((Comparable)pk)) == 0) {
750	<	dir = (c == pc) ? 0 : c.getName().compareTo(pc.getName());
751	<	TreeNode r = null, s = null, pl, pr;
752	<	if (dir >= 0) {
753	<	if ((pl = p.left) != null && h <= pl.hash)
754	<	s = pl;
755	<	}
756	<	else if ((pr = p.right) != null && h >= pr.hash)
757	<	s = pr;
758	<	if (s != null && (r = getTreeNode(h, k, s)) != null)
759	<	return r;
760	<	}
761	<	}
762	<	else
763	<	dir = (h < ph) ? -1 : 1;
764	<	p = (dir > 0) ? p.right : p.left;
765	<	}
766	<	return null;
639	>	public final K getKey()     { return key; }
640	>	public final V getValue()   { return val; }
641	>	public final int hashCode() { return key.hashCode() ^ val.hashCode(); }
642	>	public final String toString() { return key + "=" + val; }
643	>	public final V setValue(V value) {
644	>	throw new UnsupportedOperationException();
645		}
646
647	<	/**
648	<	* Wrapper for getTreeNode used by CHM.get. Tries to obtain
649	<	* read-lock to call getTreeNode, but during failure to get
650	<	* lock, searches along next links.
651	<	*/
652	<	final Object getValue(int h, Object k) {
653	<	Node r = null;
776	<	int c = getState(); // Must read lock state first
777	<	for (Node e = first; e != null; e = e.next) {
778	<	if (c <= 0 && compareAndSetState(c, c - 1)) {
779	<	try {
780	<	r = getTreeNode(h, k, root);
781	<	} finally {
782	<	releaseShared(0);
783	<	}
784	<	break;
785	<	}
786	<	else if ((e.hash & HASH_BITS) == h && k.equals(e.key)) {
787	<	r = e;
788	<	break;
789	<	}
790	<	else
791	<	c = getState();
792	<	}
793	<	return r == null ? null : r.val;
647	>	public final boolean equals(Object o) {
648	>	Object k, v, u; Map.Entry<?,?> e;
649	>	return ((o instanceof Map.Entry) &&
650	>	(k = (e = (Map.Entry<?,?>)o).getKey()) != null &&
651	>	(v = e.getValue()) != null &&
652	>	(k == key || k.equals(key)) &&
653	>	(v == (u = val) || v.equals(u)));
654		}
655
656		/**
657	<	* Finds or adds a node.
798	<	* @return null if added
657	>	* Virtualized support for map.get(); overridden in subclasses.
658		*/
659	<	@SuppressWarnings("unchecked") // suppress Comparable cast warning
660	<	final TreeNode putTreeNode(int h, Object k, Object v) {
661	<	Class<?> c = k.getClass();
662	<	TreeNode pp = root, p = null;
663	<	int dir = 0;
664	<	while (pp != null) { // find existing node or leaf to insert at
665	<	int ph;  Object pk; Class<?> pc;
666	<	p = pp;
667	<	if ((ph = p.hash) == h) {
809	<	if ((pk = p.key) == k || k.equals(pk))
810	<	return p;
811	<	if (c != (pc = pk.getClass()) ||
812	<	!(k instanceof Comparable) ||
813	<	(dir = ((Comparable)k).compareTo((Comparable)pk)) == 0) {
814	<	dir = (c == pc) ? 0 : c.getName().compareTo(pc.getName());
815	<	TreeNode r = null, s = null, pl, pr;
816	<	if (dir >= 0) {
817	<	if ((pl = p.left) != null && h <= pl.hash)
818	<	s = pl;
819	<	}
820	<	else if ((pr = p.right) != null && h >= pr.hash)
821	<	s = pr;
822	<	if (s != null && (r = getTreeNode(h, k, s)) != null)
823	<	return r;
824	<	}
825	<	}
826	<	else
827	<	dir = (h < ph) ? -1 : 1;
828	<	pp = (dir > 0) ? p.right : p.left;
829	<	}
830	<
831	<	TreeNode f = first;
832	<	TreeNode x = first = new TreeNode(h, k, v, f, p);
833	<	if (p == null)
834	<	root = x;
835	<	else { // attach and rebalance; adapted from CLR
836	<	TreeNode xp, xpp;
837	<	if (f != null)
838	<	f.prev = x;
839	<	if (dir <= 0)
840	<	p.left = x;
841	<	else
842	<	p.right = x;
843	<	x.red = true;
844	<	while (x != null && (xp = x.parent) != null && xp.red &&
845	<	(xpp = xp.parent) != null) {
846	<	TreeNode xppl = xpp.left;
847	<	if (xp == xppl) {
848	<	TreeNode y = xpp.right;
849	<	if (y != null && y.red) {
850	<	y.red = false;
851	<	xp.red = false;
852	<	xpp.red = true;
853	<	x = xpp;
854	<	}
855	<	else {
856	<	if (x == xp.right) {
857	<	rotateLeft(x = xp);
858	<	xpp = (xp = x.parent) == null ? null : xp.parent;
859	<	}
860	<	if (xp != null) {
861	<	xp.red = false;
862	<	if (xpp != null) {
863	<	xpp.red = true;
864	<	rotateRight(xpp);
865	<	}
866	<	}
867	<	}
868	<	}
869	<	else {
870	<	TreeNode y = xppl;
871	<	if (y != null && y.red) {
872	<	y.red = false;
873	<	xp.red = false;
874	<	xpp.red = true;
875	<	x = xpp;
876	<	}
877	<	else {
878	<	if (x == xp.left) {
879	<	rotateRight(x = xp);
880	<	xpp = (xp = x.parent) == null ? null : xp.parent;
881	<	}
882	<	if (xp != null) {
883	<	xp.red = false;
884	<	if (xpp != null) {
885	<	xpp.red = true;
886	<	rotateLeft(xpp);
887	<	}
888	<	}
889	<	}
890	<	}
891	<	}
892	<	TreeNode r = root;
893	<	if (r != null && r.red)
894	<	r.red = false;
659	>	Node<K,V> find(int h, Object k) {
660	>	Node<K,V> e = this;
661	>	if (k != null) {
662	>	do {
663	>	K ek;
664	>	if (e.hash == h &&
665	>	((ek = e.key) == k || (ek != null && k.equals(ek))))
666	>	return e;
667	>	} while ((e = e.next) != null);
668		}
669		return null;
670		}
898	–
899	–	/**
900	–	* Removes the given node, that must be present before this
901	–	* call.  This is messier than typical red-black deletion code
902	–	* because we cannot swap the contents of an interior node
903	–	* with a leaf successor that is pinned by "next" pointers
904	–	* that are accessible independently of lock. So instead we
905	–	* swap the tree linkages.
906	–	*/
907	–	final void deleteTreeNode(TreeNode p) {
908	–	TreeNode next = (TreeNode)p.next; // unlink traversal pointers
909	–	TreeNode pred = p.prev;
910	–	if (pred == null)
911	–	first = next;
912	–	else
913	–	pred.next = next;
914	–	if (next != null)
915	–	next.prev = pred;
916	–	TreeNode replacement;
917	–	TreeNode pl = p.left;
918	–	TreeNode pr = p.right;
919	–	if (pl != null && pr != null) {
920	–	TreeNode s = pr, sl;
921	–	while ((sl = s.left) != null) // find successor
922	–	s = sl;
923	–	boolean c = s.red; s.red = p.red; p.red = c; // swap colors
924	–	TreeNode sr = s.right;
925	–	TreeNode pp = p.parent;
926	–	if (s == pr) { // p was s's direct parent
927	–	p.parent = s;
928	–	s.right = p;
929	–	}
930	–	else {
931	–	TreeNode sp = s.parent;
932	–	if ((p.parent = sp) != null) {
933	–	if (s == sp.left)
934	–	sp.left = p;
935	–	else
936	–	sp.right = p;
937	–	}
938	–	if ((s.right = pr) != null)
939	–	pr.parent = s;
940	–	}
941	–	p.left = null;
942	–	if ((p.right = sr) != null)
943	–	sr.parent = p;
944	–	if ((s.left = pl) != null)
945	–	pl.parent = s;
946	–	if ((s.parent = pp) == null)
947	–	root = s;
948	–	else if (p == pp.left)
949	–	pp.left = s;
950	–	else
951	–	pp.right = s;
952	–	replacement = sr;
953	–	}
954	–	else
955	–	replacement = (pl != null) ? pl : pr;
956	–	TreeNode pp = p.parent;
957	–	if (replacement == null) {
958	–	if (pp == null) {
959	–	root = null;
960	–	return;
961	–	}
962	–	replacement = p;
963	–	}
964	–	else {
965	–	replacement.parent = pp;
966	–	if (pp == null)
967	–	root = replacement;
968	–	else if (p == pp.left)
969	–	pp.left = replacement;
970	–	else
971	–	pp.right = replacement;
972	–	p.left = p.right = p.parent = null;
973	–	}
974	–	if (!p.red) { // rebalance, from CLR
975	–	TreeNode x = replacement;
976	–	while (x != null) {
977	–	TreeNode xp, xpl;
978	–	if (x.red || (xp = x.parent) == null) {
979	–	x.red = false;
980	–	break;
981	–	}
982	–	if (x == (xpl = xp.left)) {
983	–	TreeNode sib = xp.right;
984	–	if (sib != null && sib.red) {
985	–	sib.red = false;
986	–	xp.red = true;
987	–	rotateLeft(xp);
988	–	sib = (xp = x.parent) == null ? null : xp.right;
989	–	}
990	–	if (sib == null)
991	–	x = xp;
992	–	else {
993	–	TreeNode sl = sib.left, sr = sib.right;
994	–	if ((sr == null || !sr.red) &&
995	–	(sl == null || !sl.red)) {
996	–	sib.red = true;
997	–	x = xp;
998	–	}
999	–	else {
1000	–	if (sr == null || !sr.red) {
1001	–	if (sl != null)
1002	–	sl.red = false;
1003	–	sib.red = true;
1004	–	rotateRight(sib);
1005	–	sib = (xp = x.parent) == null ? null : xp.right;
1006	–	}
1007	–	if (sib != null) {
1008	–	sib.red = (xp == null) ? false : xp.red;
1009	–	if ((sr = sib.right) != null)
1010	–	sr.red = false;
1011	–	}
1012	–	if (xp != null) {
1013	–	xp.red = false;
1014	–	rotateLeft(xp);
1015	–	}
1016	–	x = root;
1017	–	}
1018	–	}
1019	–	}
1020	–	else { // symmetric
1021	–	TreeNode sib = xpl;
1022	–	if (sib != null && sib.red) {
1023	–	sib.red = false;
1024	–	xp.red = true;
1025	–	rotateRight(xp);
1026	–	sib = (xp = x.parent) == null ? null : xp.left;
1027	–	}
1028	–	if (sib == null)
1029	–	x = xp;
1030	–	else {
1031	–	TreeNode sl = sib.left, sr = sib.right;
1032	–	if ((sl == null || !sl.red) &&
1033	–	(sr == null || !sr.red)) {
1034	–	sib.red = true;
1035	–	x = xp;
1036	–	}
1037	–	else {
1038	–	if (sl == null || !sl.red) {
1039	–	if (sr != null)
1040	–	sr.red = false;
1041	–	sib.red = true;
1042	–	rotateLeft(sib);
1043	–	sib = (xp = x.parent) == null ? null : xp.left;
1044	–	}
1045	–	if (sib != null) {
1046	–	sib.red = (xp == null) ? false : xp.red;
1047	–	if ((sl = sib.left) != null)
1048	–	sl.red = false;
1049	–	}
1050	–	if (xp != null) {
1051	–	xp.red = false;
1052	–	rotateRight(xp);
1053	–	}
1054	–	x = root;
1055	–	}
1056	–	}
1057	–	}
1058	–	}
1059	–	}
1060	–	if (p == replacement && (pp = p.parent) != null) {
1061	–	if (p == pp.left) // detach pointers
1062	–	pp.left = null;
1063	–	else if (p == pp.right)
1064	–	pp.right = null;
1065	–	p.parent = null;
1066	–	}
1067	–	}
671		}
672
673	<	/* ---------------- Collision reduction methods -------------- */
673	>	/* ---------------- Static utilities -------------- */
674
675		/**
676	<	* Spreads higher bits to lower, and also forces top 2 bits to 0.
677	<	* Because the table uses power-of-two masking, sets of hashes
678	<	* that vary only in bits above the current mask will always
679	<	* collide. (Among known examples are sets of Float keys holding
680	<	* consecutive whole numbers in small tables.)  To counter this,
681	<	* we apply a transform that spreads the impact of higher bits
676	>	* Spreads (XORs) higher bits of hash to lower and also forces top
677	>	* bit to 0. Because the table uses power-of-two masking, sets of
678	>	* hashes that vary only in bits above the current mask will
679	>	* always collide. (Among known examples are sets of Float keys
680	>	* holding consecutive whole numbers in small tables.)  So we
681	>	* apply a transform that spreads the impact of higher bits
682		* downward. There is a tradeoff between speed, utility, and
683		* quality of bit-spreading. Because many common sets of hashes
684	<	* are already reasonably distributed across bits (so don't benefit
685	<	* from spreading), and because we use trees to handle large sets
686	<	* of collisions in bins, we don't need excessively high quality.
687	<	*/
688	<	private static final int spread(int h) {
689	<	h ^= (h >>> 18) ^ (h >>> 12);
1087	<	return (h ^ (h >>> 10)) & HASH_BITS;
1088	<	}
1089	<
1090	<	/**
1091	<	* Replaces a list bin with a tree bin. Call only when locked.
1092	<	* Fails to replace if the given key is non-comparable or table
1093	<	* is, or needs, resizing.
684	>	* are already reasonably distributed (so don't benefit from
685	>	* spreading), and because we use trees to handle large sets of
686	>	* collisions in bins, we just XOR some shifted bits in the
687	>	* cheapest possible way to reduce systematic lossage, as well as
688	>	* to incorporate impact of the highest bits that would otherwise
689	>	* never be used in index calculations because of table bounds.
690		*/
691	<	private final void replaceWithTreeBin(Node[] tab, int index, Object key) {
692	<	if ((key instanceof Comparable) &&
1097	<	(tab.length >= MAXIMUM_CAPACITY || counter.sum() < (long)sizeCtl)) {
1098	<	TreeBin t = new TreeBin();
1099	<	for (Node e = tabAt(tab, index); e != null; e = e.next)
1100	<	t.putTreeNode(e.hash & HASH_BITS, e.key, e.val);
1101	<	setTabAt(tab, index, new Node(MOVED, t, null, null));
1102	<	}
1103	<	}
1104	<
1105	<	/* ---------------- Internal access and update methods -------------- */
1106	<
1107	<	/** Implementation for get and containsKey */
1108	<	private final Object internalGet(Object k) {
1109	<	int h = spread(k.hashCode());
1110	<	retry: for (Node[] tab = table; tab != null;) {
1111	<	Node e, p; Object ek, ev; int eh;      // locals to read fields once
1112	<	for (e = tabAt(tab, (tab.length - 1) & h); e != null; e = e.next) {
1113	<	if ((eh = e.hash) == MOVED) {
1114	<	if ((ek = e.key) instanceof TreeBin)  // search TreeBin
1115	<	return ((TreeBin)ek).getValue(h, k);
1116	<	else {                        // restart with new table
1117	<	tab = (Node[])ek;
1118	<	continue retry;
1119	<	}
1120	<	}
1121	<	else if ((eh & HASH_BITS) == h && (ev = e.val) != null &&
1122	<	((ek = e.key) == k || k.equals(ek)))
1123	<	return ev;
1124	<	}
1125	<	break;
1126	<	}
1127	<	return null;
1128	<	}
1129	<
1130	<	/**
1131	<	* Implementation for the four public remove/replace methods:
1132	<	* Replaces node value with v, conditional upon match of cv if
1133	<	* non-null.  If resulting value is null, delete.
1134	<	*/
1135	<	private final Object internalReplace(Object k, Object v, Object cv) {
1136	<	int h = spread(k.hashCode());
1137	<	Object oldVal = null;
1138	<	for (Node[] tab = table;;) {
1139	<	Node f; int i, fh; Object fk;
1140	<	if (tab == null ||
1141	<	(f = tabAt(tab, i = (tab.length - 1) & h)) == null)
1142	<	break;
1143	<	else if ((fh = f.hash) == MOVED) {
1144	<	if ((fk = f.key) instanceof TreeBin) {
1145	<	TreeBin t = (TreeBin)fk;
1146	<	boolean validated = false;
1147	<	boolean deleted = false;
1148	<	t.acquire(0);
1149	<	try {
1150	<	if (tabAt(tab, i) == f) {
1151	<	validated = true;
1152	<	TreeNode p = t.getTreeNode(h, k, t.root);
1153	<	if (p != null) {
1154	<	Object pv = p.val;
1155	<	if (cv == null || cv == pv || cv.equals(pv)) {
1156	<	oldVal = pv;
1157	<	if ((p.val = v) == null) {
1158	<	deleted = true;
1159	<	t.deleteTreeNode(p);
1160	<	}
1161	<	}
1162	<	}
1163	<	}
1164	<	} finally {
1165	<	t.release(0);
1166	<	}
1167	<	if (validated) {
1168	<	if (deleted)
1169	<	counter.add(-1L);
1170	<	break;
1171	<	}
1172	<	}
1173	<	else
1174	<	tab = (Node[])fk;
1175	<	}
1176	<	else if ((fh & HASH_BITS) != h && f.next == null) // precheck
1177	<	break;                          // rules out possible existence
1178	<	else if ((fh & LOCKED) != 0) {
1179	<	checkForResize();               // try resizing if can't get lock
1180	<	f.tryAwaitLock(tab, i);
1181	<	}
1182	<	else if (f.casHash(fh, fh | LOCKED)) {
1183	<	boolean validated = false;
1184	<	boolean deleted = false;
1185	<	try {
1186	<	if (tabAt(tab, i) == f) {
1187	<	validated = true;
1188	<	for (Node e = f, pred = null;;) {
1189	<	Object ek, ev;
1190	<	if ((e.hash & HASH_BITS) == h &&
1191	<	((ev = e.val) != null) &&
1192	<	((ek = e.key) == k || k.equals(ek))) {
1193	<	if (cv == null || cv == ev || cv.equals(ev)) {
1194	<	oldVal = ev;
1195	<	if ((e.val = v) == null) {
1196	<	deleted = true;
1197	<	Node en = e.next;
1198	<	if (pred != null)
1199	<	pred.next = en;
1200	<	else
1201	<	setTabAt(tab, i, en);
1202	<	}
1203	<	}
1204	<	break;
1205	<	}
1206	<	pred = e;
1207	<	if ((e = e.next) == null)
1208	<	break;
1209	<	}
1210	<	}
1211	<	} finally {
1212	<	if (!f.casHash(fh | LOCKED, fh)) {
1213	<	f.hash = fh;
1214	<	synchronized (f) { f.notifyAll(); };
1215	<	}
1216	<	}
1217	<	if (validated) {
1218	<	if (deleted)
1219	<	counter.add(-1L);
1220	<	break;
1221	<	}
1222	<	}
1223	<	}
1224	<	return oldVal;
1225	<	}
1226	<
1227	<	/*
1228	<	* Internal versions of the five insertion methods, each a
1229	<	* little more complicated than the last. All have
1230	<	* the same basic structure as the first (internalPut):
1231	<	*  1. If table uninitialized, create
1232	<	*  2. If bin empty, try to CAS new node
1233	<	*  3. If bin stale, use new table
1234	<	*  4. if bin converted to TreeBin, validate and relay to TreeBin methods
1235	<	*  5. Lock and validate; if valid, scan and add or update
1236	<	*
1237	<	* The others interweave other checks and/or alternative actions:
1238	<	*  * Plain put checks for and performs resize after insertion.
1239	<	*  * putIfAbsent prescans for mapping without lock (and fails to add
1240	<	*    if present), which also makes pre-emptive resize checks worthwhile.
1241	<	*  * computeIfAbsent extends form used in putIfAbsent with additional
1242	<	*    mechanics to deal with, calls, potential exceptions and null
1243	<	*    returns from function call.
1244	<	*  * compute uses the same function-call mechanics, but without
1245	<	*    the prescans
1246	<	*  * putAll attempts to pre-allocate enough table space
1247	<	*    and more lazily performs count updates and checks.
1248	<	*
1249	<	* Someday when details settle down a bit more, it might be worth
1250	<	* some factoring to reduce sprawl.
1251	<	*/
1252	<
1253	<	/** Implementation for put */
1254	<	private final Object internalPut(Object k, Object v) {
1255	<	int h = spread(k.hashCode());
1256	<	int count = 0;
1257	<	for (Node[] tab = table;;) {
1258	<	int i; Node f; int fh; Object fk;
1259	<	if (tab == null)
1260	<	tab = initTable();
1261	<	else if ((f = tabAt(tab, i = (tab.length - 1) & h)) == null) {
1262	<	if (casTabAt(tab, i, null, new Node(h, k, v, null)))
1263	<	break;                   // no lock when adding to empty bin
1264	<	}
1265	<	else if ((fh = f.hash) == MOVED) {
1266	<	if ((fk = f.key) instanceof TreeBin) {
1267	<	TreeBin t = (TreeBin)fk;
1268	<	Object oldVal = null;
1269	<	t.acquire(0);
1270	<	try {
1271	<	if (tabAt(tab, i) == f) {
1272	<	count = 2;
1273	<	TreeNode p = t.putTreeNode(h, k, v);
1274	<	if (p != null) {
1275	<	oldVal = p.val;
1276	<	p.val = v;
1277	<	}
1278	<	}
1279	<	} finally {
1280	<	t.release(0);
1281	<	}
1282	<	if (count != 0) {
1283	<	if (oldVal != null)
1284	<	return oldVal;
1285	<	break;
1286	<	}
1287	<	}
1288	<	else
1289	<	tab = (Node[])fk;
1290	<	}
1291	<	else if ((fh & LOCKED) != 0) {
1292	<	checkForResize();
1293	<	f.tryAwaitLock(tab, i);
1294	<	}
1295	<	else if (f.casHash(fh, fh | LOCKED)) {
1296	<	Object oldVal = null;
1297	<	try {                        // needed in case equals() throws
1298	<	if (tabAt(tab, i) == f) {
1299	<	count = 1;
1300	<	for (Node e = f;; ++count) {
1301	<	Object ek, ev;
1302	<	if ((e.hash & HASH_BITS) == h &&
1303	<	(ev = e.val) != null &&
1304	<	((ek = e.key) == k || k.equals(ek))) {
1305	<	oldVal = ev;
1306	<	e.val = v;
1307	<	break;
1308	<	}
1309	<	Node last = e;
1310	<	if ((e = e.next) == null) {
1311	<	last.next = new Node(h, k, v, null);
1312	<	if (count >= TREE_THRESHOLD)
1313	<	replaceWithTreeBin(tab, i, k);
1314	<	break;
1315	<	}
1316	<	}
1317	<	}
1318	<	} finally {                  // unlock and signal if needed
1319	<	if (!f.casHash(fh | LOCKED, fh)) {
1320	<	f.hash = fh;
1321	<	synchronized (f) { f.notifyAll(); };
1322	<	}
1323	<	}
1324	<	if (count != 0) {
1325	<	if (oldVal != null)
1326	<	return oldVal;
1327	<	if (tab.length <= 64)
1328	<	count = 2;
1329	<	break;
1330	<	}
1331	<	}
1332	<	}
1333	<	counter.add(1L);
1334	<	if (count > 1)
1335	<	checkForResize();
1336	<	return null;
1337	<	}
1338	<
1339	<	/** Implementation for putIfAbsent */
1340	<	private final Object internalPutIfAbsent(Object k, Object v) {
1341	<	int h = spread(k.hashCode());
1342	<	int count = 0;
1343	<	for (Node[] tab = table;;) {
1344	<	int i; Node f; int fh; Object fk, fv;
1345	<	if (tab == null)
1346	<	tab = initTable();
1347	<	else if ((f = tabAt(tab, i = (tab.length - 1) & h)) == null) {
1348	<	if (casTabAt(tab, i, null, new Node(h, k, v, null)))
1349	<	break;
1350	<	}
1351	<	else if ((fh = f.hash) == MOVED) {
1352	<	if ((fk = f.key) instanceof TreeBin) {
1353	<	TreeBin t = (TreeBin)fk;
1354	<	Object oldVal = null;
1355	<	t.acquire(0);
1356	<	try {
1357	<	if (tabAt(tab, i) == f) {
1358	<	count = 2;
1359	<	TreeNode p = t.putTreeNode(h, k, v);
1360	<	if (p != null)
1361	<	oldVal = p.val;
1362	<	}
1363	<	} finally {
1364	<	t.release(0);
1365	<	}
1366	<	if (count != 0) {
1367	<	if (oldVal != null)
1368	<	return oldVal;
1369	<	break;
1370	<	}
1371	<	}
1372	<	else
1373	<	tab = (Node[])fk;
1374	<	}
1375	<	else if ((fh & HASH_BITS) == h && (fv = f.val) != null &&
1376	<	((fk = f.key) == k || k.equals(fk)))
1377	<	return fv;
1378	<	else {
1379	<	Node g = f.next;
1380	<	if (g != null) { // at least 2 nodes -- search and maybe resize
1381	<	for (Node e = g;;) {
1382	<	Object ek, ev;
1383	<	if ((e.hash & HASH_BITS) == h && (ev = e.val) != null &&
1384	<	((ek = e.key) == k || k.equals(ek)))
1385	<	return ev;
1386	<	if ((e = e.next) == null) {
1387	<	checkForResize();
1388	<	break;
1389	<	}
1390	<	}
1391	<	}
1392	<	if (((fh = f.hash) & LOCKED) != 0) {
1393	<	checkForResize();
1394	<	f.tryAwaitLock(tab, i);
1395	<	}
1396	<	else if (tabAt(tab, i) == f && f.casHash(fh, fh | LOCKED)) {
1397	<	Object oldVal = null;
1398	<	try {
1399	<	if (tabAt(tab, i) == f) {
1400	<	count = 1;
1401	<	for (Node e = f;; ++count) {
1402	<	Object ek, ev;
1403	<	if ((e.hash & HASH_BITS) == h &&
1404	<	(ev = e.val) != null &&
1405	<	((ek = e.key) == k || k.equals(ek))) {
1406	<	oldVal = ev;
1407	<	break;
1408	<	}
1409	<	Node last = e;
1410	<	if ((e = e.next) == null) {
1411	<	last.next = new Node(h, k, v, null);
1412	<	if (count >= TREE_THRESHOLD)
1413	<	replaceWithTreeBin(tab, i, k);
1414	<	break;
1415	<	}
1416	<	}
1417	<	}
1418	<	} finally {
1419	<	if (!f.casHash(fh | LOCKED, fh)) {
1420	<	f.hash = fh;
1421	<	synchronized (f) { f.notifyAll(); };
1422	<	}
1423	<	}
1424	<	if (count != 0) {
1425	<	if (oldVal != null)
1426	<	return oldVal;
1427	<	if (tab.length <= 64)
1428	<	count = 2;
1429	<	break;
1430	<	}
1431	<	}
1432	<	}
1433	<	}
1434	<	counter.add(1L);
1435	<	if (count > 1)
1436	<	checkForResize();
1437	<	return null;
1438	<	}
1439	<
1440	<	/** Implementation for computeIfAbsent */
1441	<	private final Object internalComputeIfAbsent(K k,
1442	<	MappingFunction<? super K, ?> mf) {
1443	<	int h = spread(k.hashCode());
1444	<	Object val = null;
1445	<	int count = 0;
1446	<	for (Node[] tab = table;;) {
1447	<	Node f; int i, fh; Object fk, fv;
1448	<	if (tab == null)
1449	<	tab = initTable();
1450	<	else if ((f = tabAt(tab, i = (tab.length - 1) & h)) == null) {
1451	<	Node node = new Node(fh = h | LOCKED, k, null, null);
1452	<	if (casTabAt(tab, i, null, node)) {
1453	<	count = 1;
1454	<	try {
1455	<	if ((val = mf.map(k)) != null)
1456	<	node.val = val;
1457	<	} finally {
1458	<	if (val == null)
1459	<	setTabAt(tab, i, null);
1460	<	if (!node.casHash(fh, h)) {
1461	<	node.hash = h;
1462	<	synchronized (node) { node.notifyAll(); };
1463	<	}
1464	<	}
1465	<	}
1466	<	if (count != 0)
1467	<	break;
1468	<	}
1469	<	else if ((fh = f.hash) == MOVED) {
1470	<	if ((fk = f.key) instanceof TreeBin) {
1471	<	TreeBin t = (TreeBin)fk;
1472	<	boolean added = false;
1473	<	t.acquire(0);
1474	<	try {
1475	<	if (tabAt(tab, i) == f) {
1476	<	count = 1;
1477	<	TreeNode p = t.getTreeNode(h, k, t.root);
1478	<	if (p != null)
1479	<	val = p.val;
1480	<	else if ((val = mf.map(k)) != null) {
1481	<	added = true;
1482	<	count = 2;
1483	<	t.putTreeNode(h, k, val);
1484	<	}
1485	<	}
1486	<	} finally {
1487	<	t.release(0);
1488	<	}
1489	<	if (count != 0) {
1490	<	if (!added)
1491	<	return val;
1492	<	break;
1493	<	}
1494	<	}
1495	<	else
1496	<	tab = (Node[])fk;
1497	<	}
1498	<	else if ((fh & HASH_BITS) == h && (fv = f.val) != null &&
1499	<	((fk = f.key) == k || k.equals(fk)))
1500	<	return fv;
1501	<	else {
1502	<	Node g = f.next;
1503	<	if (g != null) {
1504	<	for (Node e = g;;) {
1505	<	Object ek, ev;
1506	<	if ((e.hash & HASH_BITS) == h && (ev = e.val) != null &&
1507	<	((ek = e.key) == k || k.equals(ek)))
1508	<	return ev;
1509	<	if ((e = e.next) == null) {
1510	<	checkForResize();
1511	<	break;
1512	<	}
1513	<	}
1514	<	}
1515	<	if (((fh = f.hash) & LOCKED) != 0) {
1516	<	checkForResize();
1517	<	f.tryAwaitLock(tab, i);
1518	<	}
1519	<	else if (tabAt(tab, i) == f && f.casHash(fh, fh | LOCKED)) {
1520	<	boolean added = false;
1521	<	try {
1522	<	if (tabAt(tab, i) == f) {
1523	<	count = 1;
1524	<	for (Node e = f;; ++count) {
1525	<	Object ek, ev;
1526	<	if ((e.hash & HASH_BITS) == h &&
1527	<	(ev = e.val) != null &&
1528	<	((ek = e.key) == k || k.equals(ek))) {
1529	<	val = ev;
1530	<	break;
1531	<	}
1532	<	Node last = e;
1533	<	if ((e = e.next) == null) {
1534	<	if ((val = mf.map(k)) != null) {
1535	<	added = true;
1536	<	last.next = new Node(h, k, val, null);
1537	<	if (count >= TREE_THRESHOLD)
1538	<	replaceWithTreeBin(tab, i, k);
1539	<	}
1540	<	break;
1541	<	}
1542	<	}
1543	<	}
1544	<	} finally {
1545	<	if (!f.casHash(fh | LOCKED, fh)) {
1546	<	f.hash = fh;
1547	<	synchronized (f) { f.notifyAll(); };
1548	<	}
1549	<	}
1550	<	if (count != 0) {
1551	<	if (!added)
1552	<	return val;
1553	<	if (tab.length <= 64)
1554	<	count = 2;
1555	<	break;
1556	<	}
1557	<	}
1558	<	}
1559	<	}
1560	<	if (val != null) {
1561	<	counter.add(1L);
1562	<	if (count > 1)
1563	<	checkForResize();
1564	<	}
1565	<	return val;
1566	<	}
1567	<
1568	<	/** Implementation for compute */
1569	<	@SuppressWarnings("unchecked")
1570	<	private final Object internalCompute(K k,
1571	<	RemappingFunction<? super K, V> mf) {
1572	<	int h = spread(k.hashCode());
1573	<	Object val = null;
1574	<	int delta = 0;
1575	<	int count = 0;
1576	<	for (Node[] tab = table;;) {
1577	<	Node f; int i, fh; Object fk;
1578	<	if (tab == null)
1579	<	tab = initTable();
1580	<	else if ((f = tabAt(tab, i = (tab.length - 1) & h)) == null) {
1581	<	Node node = new Node(fh = h | LOCKED, k, null, null);
1582	<	if (casTabAt(tab, i, null, node)) {
1583	<	try {
1584	<	count = 1;
1585	<	if ((val = mf.remap(k, null)) != null) {
1586	<	node.val = val;
1587	<	delta = 1;
1588	<	}
1589	<	} finally {
1590	<	if (delta == 0)
1591	<	setTabAt(tab, i, null);
1592	<	if (!node.casHash(fh, h)) {
1593	<	node.hash = h;
1594	<	synchronized (node) { node.notifyAll(); };
1595	<	}
1596	<	}
1597	<	}
1598	<	if (count != 0)
1599	<	break;
1600	<	}
1601	<	else if ((fh = f.hash) == MOVED) {
1602	<	if ((fk = f.key) instanceof TreeBin) {
1603	<	TreeBin t = (TreeBin)fk;
1604	<	t.acquire(0);
1605	<	try {
1606	<	if (tabAt(tab, i) == f) {
1607	<	count = 1;
1608	<	TreeNode p = t.getTreeNode(h, k, t.root);
1609	<	Object pv = (p == null) ? null : p.val;
1610	<	if ((val = mf.remap(k, (V)pv)) != null) {
1611	<	if (p != null)
1612	<	p.val = val;
1613	<	else {
1614	<	count = 2;
1615	<	delta = 1;
1616	<	t.putTreeNode(h, k, val);
1617	<	}
1618	<	}
1619	<	else if (p != null) {
1620	<	delta = -1;
1621	<	t.deleteTreeNode(p);
1622	<	}
1623	<	}
1624	<	} finally {
1625	<	t.release(0);
1626	<	}
1627	<	if (count != 0)
1628	<	break;
1629	<	}
1630	<	else
1631	<	tab = (Node[])fk;
1632	<	}
1633	<	else if ((fh & LOCKED) != 0) {
1634	<	checkForResize();
1635	<	f.tryAwaitLock(tab, i);
1636	<	}
1637	<	else if (f.casHash(fh, fh | LOCKED)) {
1638	<	try {
1639	<	if (tabAt(tab, i) == f) {
1640	<	count = 1;
1641	<	for (Node e = f, pred = null;; ++count) {
1642	<	Object ek, ev;
1643	<	if ((e.hash & HASH_BITS) == h &&
1644	<	(ev = e.val) != null &&
1645	<	((ek = e.key) == k || k.equals(ek))) {
1646	<	val = mf.remap(k, (V)ev);
1647	<	if (val != null)
1648	<	e.val = val;
1649	<	else {
1650	<	delta = -1;
1651	<	Node en = e.next;
1652	<	if (pred != null)
1653	<	pred.next = en;
1654	<	else
1655	<	setTabAt(tab, i, en);
1656	<	}
1657	<	break;
1658	<	}
1659	<	pred = e;
1660	<	if ((e = e.next) == null) {
1661	<	if ((val = mf.remap(k, null)) != null) {
1662	<	pred.next = new Node(h, k, val, null);
1663	<	delta = 1;
1664	<	if (count >= TREE_THRESHOLD)
1665	<	replaceWithTreeBin(tab, i, k);
1666	<	}
1667	<	break;
1668	<	}
1669	<	}
1670	<	}
1671	<	} finally {
1672	<	if (!f.casHash(fh | LOCKED, fh)) {
1673	<	f.hash = fh;
1674	<	synchronized (f) { f.notifyAll(); };
1675	<	}
1676	<	}
1677	<	if (count != 0) {
1678	<	if (tab.length <= 64)
1679	<	count = 2;
1680	<	break;
1681	<	}
1682	<	}
1683	<	}
1684	<	if (delta != 0) {
1685	<	counter.add((long)delta);
1686	<	if (count > 1)
1687	<	checkForResize();
1688	<	}
1689	<	return val;
1690	<	}
1691	<
1692	<	/** Implementation for putAll */
1693	<	private final void internalPutAll(Map<?, ?> m) {
1694	<	tryPresize(m.size());
1695	<	long delta = 0L;     // number of uncommitted additions
1696	<	boolean npe = false; // to throw exception on exit for nulls
1697	<	try {                // to clean up counts on other exceptions
1698	<	for (Map.Entry<?, ?> entry : m.entrySet()) {
1699	<	Object k, v;
1700	<	if (entry == null || (k = entry.getKey()) == null ||
1701	<	(v = entry.getValue()) == null) {
1702	<	npe = true;
1703	<	break;
1704	<	}
1705	<	int h = spread(k.hashCode());
1706	<	for (Node[] tab = table;;) {
1707	<	int i; Node f; int fh; Object fk;
1708	<	if (tab == null)
1709	<	tab = initTable();
1710	<	else if ((f = tabAt(tab, i = (tab.length - 1) & h)) == null){
1711	<	if (casTabAt(tab, i, null, new Node(h, k, v, null))) {
1712	<	++delta;
1713	<	break;
1714	<	}
1715	<	}
1716	<	else if ((fh = f.hash) == MOVED) {
1717	<	if ((fk = f.key) instanceof TreeBin) {
1718	<	TreeBin t = (TreeBin)fk;
1719	<	boolean validated = false;
1720	<	t.acquire(0);
1721	<	try {
1722	<	if (tabAt(tab, i) == f) {
1723	<	validated = true;
1724	<	TreeNode p = t.getTreeNode(h, k, t.root);
1725	<	if (p != null)
1726	<	p.val = v;
1727	<	else {
1728	<	t.putTreeNode(h, k, v);
1729	<	++delta;
1730	<	}
1731	<	}
1732	<	} finally {
1733	<	t.release(0);
1734	<	}
1735	<	if (validated)
1736	<	break;
1737	<	}
1738	<	else
1739	<	tab = (Node[])fk;
1740	<	}
1741	<	else if ((fh & LOCKED) != 0) {
1742	<	counter.add(delta);
1743	<	delta = 0L;
1744	<	checkForResize();
1745	<	f.tryAwaitLock(tab, i);
1746	<	}
1747	<	else if (f.casHash(fh, fh | LOCKED)) {
1748	<	int count = 0;
1749	<	try {
1750	<	if (tabAt(tab, i) == f) {
1751	<	count = 1;
1752	<	for (Node e = f;; ++count) {
1753	<	Object ek, ev;
1754	<	if ((e.hash & HASH_BITS) == h &&
1755	<	(ev = e.val) != null &&
1756	<	((ek = e.key) == k || k.equals(ek))) {
1757	<	e.val = v;
1758	<	break;
1759	<	}
1760	<	Node last = e;
1761	<	if ((e = e.next) == null) {
1762	<	++delta;
1763	<	last.next = new Node(h, k, v, null);
1764	<	if (count >= TREE_THRESHOLD)
1765	<	replaceWithTreeBin(tab, i, k);
1766	<	break;
1767	<	}
1768	<	}
1769	<	}
1770	<	} finally {
1771	<	if (!f.casHash(fh | LOCKED, fh)) {
1772	<	f.hash = fh;
1773	<	synchronized (f) { f.notifyAll(); };
1774	<	}
1775	<	}
1776	<	if (count != 0) {
1777	<	if (count > 1) {
1778	<	counter.add(delta);
1779	<	delta = 0L;
1780	<	checkForResize();
1781	<	}
1782	<	break;
1783	<	}
1784	<	}
1785	<	}
1786	<	}
1787	<	} finally {
1788	<	if (delta != 0)
1789	<	counter.add(delta);
1790	<	}
1791	<	if (npe)
1792	<	throw new NullPointerException();
691	>	static final int spread(int h) {
692	>	return (h ^ (h >>> 16)) & HASH_BITS;
693		}
694
1795	–	/* ---------------- Table Initialization and Resizing -------------- */
1796	–
695		/**
696		* Returns a power of two table size for the given desired capacity.
697		* See Hackers Delight, sec 3.2
#	Line 1809 | Line 707 | public class ConcurrentHashMapV8<K, V>
707		}
708
709		/**
710	<	* Initializes table, using the size recorded in sizeCtl.
710	>	* Returns x's Class if it is of the form "class C implements
711	>	* Comparable<C>", else null.
712		*/
713	<	private final Node[] initTable() {
714	<	Node[] tab; int sc;
715	<	while ((tab = table) == null) {
716	<	if ((sc = sizeCtl) < 0)
717	<	Thread.yield(); // lost initialization race; just spin
718	<	else if (UNSAFE.compareAndSwapInt(this, sizeCtlOffset, sc, -1)) {
719	<	try {
720	<	if ((tab = table) == null) {
721	<	int n = (sc > 0) ? sc : DEFAULT_CAPACITY;
722	<	tab = table = new Node[n];
723	<	sc = n - (n >>> 2);
724	<	}
725	<	} finally {
1827	<	sizeCtl = sc;
713	>	static Class<?> comparableClassFor(Object x) {
714	>	if (x instanceof Comparable) {
715	>	Class<?> c; Type[] ts, as; Type t; ParameterizedType p;
716	>	if ((c = x.getClass()) == String.class) // bypass checks
717	>	return c;
718	>	if ((ts = c.getGenericInterfaces()) != null) {
719	>	for (int i = 0; i < ts.length; ++i) {
720	>	if (((t = ts[i]) instanceof ParameterizedType) &&
721	>	((p = (ParameterizedType)t).getRawType() ==
722	>	Comparable.class) &&
723	>	(as = p.getActualTypeArguments()) != null &&
724	>	as.length == 1 && as[0] == c) // type arg is c
725	>	return c;
726		}
1829	–	break;
1830	–	}
1831	–	}
1832	–	return tab;
1833	–	}
1834	–
1835	–	/**
1836	–	* If table is too small and not already resizing, creates next
1837	–	* table and transfers bins.  Rechecks occupancy after a transfer
1838	–	* to see if another resize is already needed because resizings
1839	–	* are lagging additions.
1840	–	*/
1841	–	private final void checkForResize() {
1842	–	Node[] tab; int n, sc;
1843	–	while ((tab = table) != null &&
1844	–	(n = tab.length) < MAXIMUM_CAPACITY &&
1845	–	(sc = sizeCtl) >= 0 && counter.sum() >= (long)sc &&
1846	–	UNSAFE.compareAndSwapInt(this, sizeCtlOffset, sc, -1)) {
1847	–	try {
1848	–	if (tab == table) {
1849	–	table = rebuild(tab);
1850	–	sc = (n << 1) - (n >>> 1);
1851	–	}
1852	–	} finally {
1853	–	sizeCtl = sc;
727		}
728		}
729	+	return null;
730		}
731
732		/**
733	<	* Tries to presize table to accommodate the given number of elements.
734	<	*
1861	<	* @param size number of elements (doesn't need to be perfectly accurate)
733	>	* Returns k.compareTo(x) if x matches kc (k's screened comparable
734	>	* class), else 0.
735		*/
736	<	private final void tryPresize(int size) {
737	<	int c = (size >= (MAXIMUM_CAPACITY >>> 1)) ? MAXIMUM_CAPACITY :
738	<	tableSizeFor(size + (size >>> 1) + 1);
739	<	int sc;
1867	<	while ((sc = sizeCtl) >= 0) {
1868	<	Node[] tab = table; int n;
1869	<	if (tab == null || (n = tab.length) == 0) {
1870	<	n = (sc > c) ? sc : c;
1871	<	if (UNSAFE.compareAndSwapInt(this, sizeCtlOffset, sc, -1)) {
1872	<	try {
1873	<	if (table == tab) {
1874	<	table = new Node[n];
1875	<	sc = n - (n >>> 2);
1876	<	}
1877	<	} finally {
1878	<	sizeCtl = sc;
1879	<	}
1880	<	}
1881	<	}
1882	<	else if (c <= sc || n >= MAXIMUM_CAPACITY)
1883	<	break;
1884	<	else if (UNSAFE.compareAndSwapInt(this, sizeCtlOffset, sc, -1)) {
1885	<	try {
1886	<	if (table == tab) {
1887	<	table = rebuild(tab);
1888	<	sc = (n << 1) - (n >>> 1);
1889	<	}
1890	<	} finally {
1891	<	sizeCtl = sc;
1892	<	}
1893	<	}
1894	<	}
736	>	@SuppressWarnings({"rawtypes","unchecked"}) // for cast to Comparable
737	>	static int compareComparables(Class<?> kc, Object k, Object x) {
738	>	return (x == null || x.getClass() != kc ? 0 :
739	>	((Comparable)k).compareTo(x));
740		}
741
742	+	/* ---------------- Table element access -------------- */
743	+
744		/*
745	<	* Moves and/or copies the nodes in each bin to new table. See
746	<	* above for explanation.
747	<	*
748	<	* @return the new table
745	>	* Volatile access methods are used for table elements as well as
746	>	* elements of in-progress next table while resizing.  All uses of
747	>	* the tab arguments must be null checked by callers.  All callers
748	>	* also paranoically precheck that tab's length is not zero (or an
749	>	* equivalent check), thus ensuring that any index argument taking
750	>	* the form of a hash value anded with (length - 1) is a valid
751	>	* index.  Note that, to be correct wrt arbitrary concurrency
752	>	* errors by users, these checks must operate on local variables,
753	>	* which accounts for some odd-looking inline assignments below.
754	>	* Note that calls to setTabAt always occur within locked regions,
755	>	* and so in principle require only release ordering, not
756	>	* full volatile semantics, but are currently coded as volatile
757	>	* writes to be conservative.
758		*/
759	<	private static final Node[] rebuild(Node[] tab) {
760	<	int n = tab.length;
761	<	Node[] nextTab = new Node[n << 1];
762	<	Node fwd = new Node(MOVED, nextTab, null, null);
1907	<	int[] buffer = null;       // holds bins to revisit; null until needed
1908	<	Node rev = null;           // reverse forwarder; null until needed
1909	<	int nbuffered = 0;         // the number of bins in buffer list
1910	<	int bufferIndex = 0;       // buffer index of current buffered bin
1911	<	int bin = n - 1;           // current non-buffered bin or -1 if none
1912	<
1913	<	for (int i = bin;;) {      // start upwards sweep
1914	<	int fh; Node f;
1915	<	if ((f = tabAt(tab, i)) == null) {
1916	<	if (bin >= 0) {    // no lock needed (or available)
1917	<	if (!casTabAt(tab, i, f, fwd))
1918	<	continue;
1919	<	}
1920	<	else {             // transiently use a locked forwarding node
1921	<	Node g = new Node(MOVED|LOCKED, nextTab, null, null);
1922	<	if (!casTabAt(tab, i, f, g))
1923	<	continue;
1924	<	setTabAt(nextTab, i, null);
1925	<	setTabAt(nextTab, i + n, null);
1926	<	setTabAt(tab, i, fwd);
1927	<	if (!g.casHash(MOVED|LOCKED, MOVED)) {
1928	<	g.hash = MOVED;
1929	<	synchronized (g) { g.notifyAll(); }
1930	<	}
1931	<	}
1932	<	}
1933	<	else if ((fh = f.hash) == MOVED) {
1934	<	Object fk = f.key;
1935	<	if (fk instanceof TreeBin) {
1936	<	TreeBin t = (TreeBin)fk;
1937	<	boolean validated = false;
1938	<	t.acquire(0);
1939	<	try {
1940	<	if (tabAt(tab, i) == f) {
1941	<	validated = true;
1942	<	splitTreeBin(nextTab, i, t);
1943	<	setTabAt(tab, i, fwd);
1944	<	}
1945	<	} finally {
1946	<	t.release(0);
1947	<	}
1948	<	if (!validated)
1949	<	continue;
1950	<	}
1951	<	}
1952	<	else if ((fh & LOCKED) == 0 && f.casHash(fh, fh|LOCKED)) {
1953	<	boolean validated = false;
1954	<	try {              // split to lo and hi lists; copying as needed
1955	<	if (tabAt(tab, i) == f) {
1956	<	validated = true;
1957	<	splitBin(nextTab, i, f);
1958	<	setTabAt(tab, i, fwd);
1959	<	}
1960	<	} finally {
1961	<	if (!f.casHash(fh | LOCKED, fh)) {
1962	<	f.hash = fh;
1963	<	synchronized (f) { f.notifyAll(); };
1964	<	}
1965	<	}
1966	<	if (!validated)
1967	<	continue;
1968	<	}
1969	<	else {
1970	<	if (buffer == null) // initialize buffer for revisits
1971	<	buffer = new int[TRANSFER_BUFFER_SIZE];
1972	<	if (bin < 0 && bufferIndex > 0) {
1973	<	int j = buffer[--bufferIndex];
1974	<	buffer[bufferIndex] = i;
1975	<	i = j;         // swap with another bin
1976	<	continue;
1977	<	}
1978	<	if (bin < 0 || nbuffered >= TRANSFER_BUFFER_SIZE) {
1979	<	f.tryAwaitLock(tab, i);
1980	<	continue;      // no other options -- block
1981	<	}
1982	<	if (rev == null)   // initialize reverse-forwarder
1983	<	rev = new Node(MOVED, tab, null, null);
1984	<	if (tabAt(tab, i) != f || (f.hash & LOCKED) == 0)
1985	<	continue;      // recheck before adding to list
1986	<	buffer[nbuffered++] = i;
1987	<	setTabAt(nextTab, i, rev);     // install place-holders
1988	<	setTabAt(nextTab, i + n, rev);
1989	<	}
1990	<
1991	<	if (bin > 0)
1992	<	i = --bin;
1993	<	else if (buffer != null && nbuffered > 0) {
1994	<	bin = -1;
1995	<	i = buffer[bufferIndex = --nbuffered];
1996	<	}
1997	<	else
1998	<	return nextTab;
1999	<	}
759	>
760	>	@SuppressWarnings("unchecked")
761	>	static final <K,V> Node<K,V> tabAt(Node<K,V>[] tab, int i) {
762	>	return (Node<K,V>)U.getObjectVolatile(tab, ((long)i << ASHIFT) + ABASE);
763		}
764
765	+	static final <K,V> boolean casTabAt(Node<K,V>[] tab, int i,
766	+	Node<K,V> c, Node<K,V> v) {
767	+	return U.compareAndSwapObject(tab, ((long)i << ASHIFT) + ABASE, c, v);
768	+	}
769	+
770	+	static final <K,V> void setTabAt(Node<K,V>[] tab, int i, Node<K,V> v) {
771	+	U.putObjectVolatile(tab, ((long)i << ASHIFT) + ABASE, v);
772	+	}
773	+
774	+	/* ---------------- Fields -------------- */
775	+
776		/**
777	<	* Splits a normal bin with list headed by e into lo and hi parts;
778	<	* installs in given table.
777	>	* The array of bins. Lazily initialized upon first insertion.
778	>	* Size is always a power of two. Accessed directly by iterators.
779		*/
780	<	private static void splitBin(Node[] nextTab, int i, Node e) {
2007	<	int bit = nextTab.length >>> 1; // bit to split on
2008	<	int runBit = e.hash & bit;
2009	<	Node lastRun = e, lo = null, hi = null;
2010	<	for (Node p = e.next; p != null; p = p.next) {
2011	<	int b = p.hash & bit;
2012	<	if (b != runBit) {
2013	<	runBit = b;
2014	<	lastRun = p;
2015	<	}
2016	<	}
2017	<	if (runBit == 0)
2018	<	lo = lastRun;
2019	<	else
2020	<	hi = lastRun;
2021	<	for (Node p = e; p != lastRun; p = p.next) {
2022	<	int ph = p.hash & HASH_BITS;
2023	<	Object pk = p.key, pv = p.val;
2024	<	if ((ph & bit) == 0)
2025	<	lo = new Node(ph, pk, pv, lo);
2026	<	else
2027	<	hi = new Node(ph, pk, pv, hi);
2028	<	}
2029	<	setTabAt(nextTab, i, lo);
2030	<	setTabAt(nextTab, i + bit, hi);
2031	<	}
780	>	transient volatile Node<K,V>[] table;
781
782		/**
783	<	* Splits a tree bin into lo and hi parts; installs in given table.
783	>	* The next table to use; non-null only while resizing.
784		*/
785	<	private static void splitTreeBin(Node[] nextTab, int i, TreeBin t) {
2037	<	int bit = nextTab.length >>> 1;
2038	<	TreeBin lt = new TreeBin();
2039	<	TreeBin ht = new TreeBin();
2040	<	int lc = 0, hc = 0;
2041	<	for (Node e = t.first; e != null; e = e.next) {
2042	<	int h = e.hash & HASH_BITS;
2043	<	Object k = e.key, v = e.val;
2044	<	if ((h & bit) == 0) {
2045	<	++lc;
2046	<	lt.putTreeNode(h, k, v);
2047	<	}
2048	<	else {
2049	<	++hc;
2050	<	ht.putTreeNode(h, k, v);
2051	<	}
2052	<	}
2053	<	Node ln, hn; // throw away trees if too small
2054	<	if (lc <= (TREE_THRESHOLD >>> 1)) {
2055	<	ln = null;
2056	<	for (Node p = lt.first; p != null; p = p.next)
2057	<	ln = new Node(p.hash, p.key, p.val, ln);
2058	<	}
2059	<	else
2060	<	ln = new Node(MOVED, lt, null, null);
2061	<	setTabAt(nextTab, i, ln);
2062	<	if (hc <= (TREE_THRESHOLD >>> 1)) {
2063	<	hn = null;
2064	<	for (Node p = ht.first; p != null; p = p.next)
2065	<	hn = new Node(p.hash, p.key, p.val, hn);
2066	<	}
2067	<	else
2068	<	hn = new Node(MOVED, ht, null, null);
2069	<	setTabAt(nextTab, i + bit, hn);
2070	<	}
785	>	private transient volatile Node<K,V>[] nextTable;
786
787		/**
788	<	* Implementation for clear. Steps through each bin, removing all
789	<	* nodes.
788	>	* Base counter value, used mainly when there is no contention,
789	>	* but also as a fallback during table initialization
790	>	* races. Updated via CAS.
791		*/
792	<	private final void internalClear() {
2077	<	long delta = 0L; // negative number of deletions
2078	<	int i = 0;
2079	<	Node[] tab = table;
2080	<	while (tab != null && i < tab.length) {
2081	<	int fh; Object fk;
2082	<	Node f = tabAt(tab, i);
2083	<	if (f == null)
2084	<	++i;
2085	<	else if ((fh = f.hash) == MOVED) {
2086	<	if ((fk = f.key) instanceof TreeBin) {
2087	<	TreeBin t = (TreeBin)fk;
2088	<	t.acquire(0);
2089	<	try {
2090	<	if (tabAt(tab, i) == f) {
2091	<	for (Node p = t.first; p != null; p = p.next) {
2092	<	p.val = null;
2093	<	--delta;
2094	<	}
2095	<	t.first = null;
2096	<	t.root = null;
2097	<	++i;
2098	<	}
2099	<	} finally {
2100	<	t.release(0);
2101	<	}
2102	<	}
2103	<	else
2104	<	tab = (Node[])fk;
2105	<	}
2106	<	else if ((fh & LOCKED) != 0) {
2107	<	counter.add(delta); // opportunistically update count
2108	<	delta = 0L;
2109	<	f.tryAwaitLock(tab, i);
2110	<	}
2111	<	else if (f.casHash(fh, fh | LOCKED)) {
2112	<	try {
2113	<	if (tabAt(tab, i) == f) {
2114	<	for (Node e = f; e != null; e = e.next) {
2115	<	e.val = null;
2116	<	--delta;
2117	<	}
2118	<	setTabAt(tab, i, null);
2119	<	++i;
2120	<	}
2121	<	} finally {
2122	<	if (!f.casHash(fh | LOCKED, fh)) {
2123	<	f.hash = fh;
2124	<	synchronized (f) { f.notifyAll(); };
2125	<	}
2126	<	}
2127	<	}
2128	<	}
2129	<	if (delta != 0)
2130	<	counter.add(delta);
2131	<	}
792	>	private transient volatile long baseCount;
793
794	<	/* ----------------Table Traversal -------------- */
794	>	/**
795	>	* Table initialization and resizing control.  When negative, the
796	>	* table is being initialized or resized: -1 for initialization,
797	>	* else -(1 + the number of active resizing threads).  Otherwise,
798	>	* when table is null, holds the initial table size to use upon
799	>	* creation, or 0 for default. After initialization, holds the
800	>	* next element count value upon which to resize the table.
801	>	*/
802	>	private transient volatile int sizeCtl;
803
804		/**
805	<	* Encapsulates traversal for methods such as containsValue; also
2137	<	* serves as a base class for other iterators.
2138	<	*
2139	<	* At each step, the iterator snapshots the key ("nextKey") and
2140	<	* value ("nextVal") of a valid node (i.e., one that, at point of
2141	<	* snapshot, has a non-null user value). Because val fields can
2142	<	* change (including to null, indicating deletion), field nextVal
2143	<	* might not be accurate at point of use, but still maintains the
2144	<	* weak consistency property of holding a value that was once
2145	<	* valid.
2146	<	*
2147	<	* Internal traversals directly access these fields, as in:
2148	<	* {@code while (it.advance() != null) { process(it.nextKey); }}
2149	<	*
2150	<	* Exported iterators must track whether the iterator has advanced
2151	<	* (in hasNext vs next) (by setting/checking/nulling field
2152	<	* nextVal), and then extract key, value, or key-value pairs as
2153	<	* return values of next().
2154	<	*
2155	<	* The iterator visits once each still-valid node that was
2156	<	* reachable upon iterator construction. It might miss some that
2157	<	* were added to a bin after the bin was visited, which is OK wrt
2158	<	* consistency guarantees. Maintaining this property in the face
2159	<	* of possible ongoing resizes requires a fair amount of
2160	<	* bookkeeping state that is difficult to optimize away amidst
2161	<	* volatile accesses.  Even so, traversal maintains reasonable
2162	<	* throughput.
2163	<	*
2164	<	* Normally, iteration proceeds bin-by-bin traversing lists.
2165	<	* However, if the table has been resized, then all future steps
2166	<	* must traverse both the bin at the current index as well as at
2167	<	* (index + baseSize); and so on for further resizings. To
2168	<	* paranoically cope with potential sharing by users of iterators
2169	<	* across threads, iteration terminates if a bounds checks fails
2170	<	* for a table read.
805	>	* The next table index (plus one) to split while resizing.
806		*/
807	<	static class InternalIterator<K,V> {
2173	<	final ConcurrentHashMapV8<K, V> map;
2174	<	Node next;           // the next entry to use
2175	<	Node last;           // the last entry used
2176	<	Object nextKey;      // cached key field of next
2177	<	Object nextVal;      // cached val field of next
2178	<	Node[] tab;          // current table; updated if resized
2179	<	int index;           // index of bin to use next
2180	<	int baseIndex;       // current index of initial table
2181	<	int baseLimit;       // index bound for initial table
2182	<	final int baseSize;  // initial table size
2183	<
2184	<	/** Creates iterator for all entries in the table. */
2185	<	InternalIterator(ConcurrentHashMapV8<K, V> map) {
2186	<	this.tab = (this.map = map).table;
2187	<	baseLimit = baseSize = (tab == null) ? 0 : tab.length;
2188	<	}
2189	<
2190	<	/** Creates iterator for clone() and split() methods. */
2191	<	InternalIterator(InternalIterator<K,V> it, boolean split) {
2192	<	this.map = it.map;
2193	<	this.tab = it.tab;
2194	<	this.baseSize = it.baseSize;
2195	<	int lo = it.baseIndex;
2196	<	int hi = this.baseLimit = it.baseLimit;
2197	<	this.index = this.baseIndex =
2198	<	(split) ? (it.baseLimit = (lo + hi + 1) >>> 1) : lo;
2199	<	}
807	>	private transient volatile int transferIndex;
808
809	<	/**
810	<	* Advances next; returns nextVal or null if terminated
811	<	* See above for explanation.
812	<	*/
2205	<	final Object advance() {
2206	<	Node e = last = next;
2207	<	Object ev = null;
2208	<	outer: do {
2209	<	if (e != null)                  // advance past used/skipped node
2210	<	e = e.next;
2211	<	while (e == null) {             // get to next non-null bin
2212	<	Node[] t; int b, i, n; Object ek; // checks must use locals
2213	<	if ((b = baseIndex) >= baseLimit || (i = index) < 0 ||
2214	<	(t = tab) == null || i >= (n = t.length))
2215	<	break outer;
2216	<	else if ((e = tabAt(t, i)) != null && e.hash == MOVED) {
2217	<	if ((ek = e.key) instanceof TreeBin)
2218	<	e = ((TreeBin)ek).first;
2219	<	else {
2220	<	tab = (Node[])ek;
2221	<	continue;           // restarts due to null val
2222	<	}
2223	<	}                           // visit upper slots if present
2224	<	index = (i += baseSize) < n ? i : (baseIndex = b + 1);
2225	<	}
2226	<	nextKey = e.key;
2227	<	} while ((ev = e.val) == null);    // skip deleted or special nodes
2228	<	next = e;
2229	<	return nextVal = ev;
2230	<	}
809	>	/**
810	>	* Spinlock (locked via CAS) used when resizing and/or creating CounterCells.
811	>	*/
812	>	private transient volatile int cellsBusy;
813
814	<	public final void remove() {
815	<	if (nextVal == null)
816	<	advance();
817	<	Node e = last;
2236	<	if (e == null)
2237	<	throw new IllegalStateException();
2238	<	last = null;
2239	<	map.remove(e.key);
2240	<	}
814	>	/**
815	>	* Table of counter cells. When non-null, size is a power of 2.
816	>	*/
817	>	private transient volatile CounterCell[] counterCells;
818
819	<	public final boolean hasNext() {
820	<	return nextVal != null || advance() != null;
821	<	}
819	>	// views
820	>	private transient KeySetView<K,V> keySet;
821	>	private transient ValuesView<K,V> values;
822	>	private transient EntrySetView<K,V> entrySet;
823
2246	–	public final boolean hasMoreElements() { return hasNext(); }
2247	–	}
824
825		/* ---------------- Public operations -------------- */
826
827		/**
828	<	* Creates a new, empty map with the default initial table size (16),
828	>	* Creates a new, empty map with the default initial table size (16).
829		*/
830		public ConcurrentHashMapV8() {
2255	–	this.counter = new LongAdder();
831		}
832
833		/**
#	Line 2271 | Line 846 | public class ConcurrentHashMapV8<K, V>
846		int cap = ((initialCapacity >= (MAXIMUM_CAPACITY >>> 1)) ?
847		MAXIMUM_CAPACITY :
848		tableSizeFor(initialCapacity + (initialCapacity >>> 1) + 1));
2274	–	this.counter = new LongAdder();
849		this.sizeCtl = cap;
850		}
851
#	Line 2281 | Line 855 | public class ConcurrentHashMapV8<K, V>
855		* @param m the map
856		*/
857		public ConcurrentHashMapV8(Map<? extends K, ? extends V> m) {
2284	–	this.counter = new LongAdder();
858		this.sizeCtl = DEFAULT_CAPACITY;
859	<	internalPutAll(m);
859	>	putAll(m);
860		}
861
862		/**
#	Line 2324 | Line 897 | public class ConcurrentHashMapV8<K, V>
897		* nonpositive
898		*/
899		public ConcurrentHashMapV8(int initialCapacity,
900	<	float loadFactor, int concurrencyLevel) {
900	>	float loadFactor, int concurrencyLevel) {
901		if (!(loadFactor > 0.0f) || initialCapacity < 0 || concurrencyLevel <= 0)
902		throw new IllegalArgumentException();
903		if (initialCapacity < concurrencyLevel)   // Use at least as many bins
904		initialCapacity = concurrencyLevel;   // as estimated threads
905		long size = (long)(1.0 + (long)initialCapacity / loadFactor);
906	<	int cap = ((size >= (long)MAXIMUM_CAPACITY) ?
907	<	MAXIMUM_CAPACITY: tableSizeFor((int)size));
2335	<	this.counter = new LongAdder();
906	>	int cap = (size >= (long)MAXIMUM_CAPACITY) ?
907	>	MAXIMUM_CAPACITY : tableSizeFor((int)size);
908		this.sizeCtl = cap;
909		}
910
911	<	/**
2340	<	* {@inheritDoc}
2341	<	*/
2342	<	public boolean isEmpty() {
2343	<	return counter.sum() <= 0L; // ignore transient negative values
2344	<	}
911	>	// Original (since JDK1.2) Map methods
912
913		/**
914		* {@inheritDoc}
915		*/
916		public int size() {
917	<	long n = counter.sum();
917	>	long n = sumCount();
918		return ((n < 0L) ? 0 :
919		(n > (long)Integer.MAX_VALUE) ? Integer.MAX_VALUE :
920		(int)n);
921		}
922
923	<	final long longSize() { // accurate version of size needed for views
924	<	long n = counter.sum();
925	<	return (n < 0L) ? 0L : n;
923	>	/**
924	>	* {@inheritDoc}
925	>	*/
926	>	public boolean isEmpty() {
927	>	return sumCount() <= 0L; // ignore transient negative values
928		}
929
930		/**
#	Line 2369 | Line 938 | public class ConcurrentHashMapV8<K, V>
938		*
939		* @throws NullPointerException if the specified key is null
940		*/
2372	–	@SuppressWarnings("unchecked")
941		public V get(Object key) {
942	<	if (key == null)
943	<	throw new NullPointerException();
944	<	return (V)internalGet(key);
942	>	Node<K,V>[] tab; Node<K,V> e, p; int n, eh; K ek;
943	>	int h = spread(key.hashCode());
944	>	if ((tab = table) != null && (n = tab.length) > 0 &&
945	>	(e = tabAt(tab, (n - 1) & h)) != null) {
946	>	if ((eh = e.hash) == h) {
947	>	if ((ek = e.key) == key || (ek != null && key.equals(ek)))
948	>	return e.val;
949	>	}
950	>	else if (eh < 0)
951	>	return (p = e.find(h, key)) != null ? p.val : null;
952	>	while ((e = e.next) != null) {
953	>	if (e.hash == h &&
954	>	((ek = e.key) == key || (ek != null && key.equals(ek))))
955	>	return e.val;
956	>	}
957	>	}
958	>	return null;
959		}
960
961		/**
962		* Tests if the specified object is a key in this table.
963		*
964	<	* @param  key   possible key
964	>	* @param  key possible key
965		* @return {@code true} if and only if the specified object
966		*         is a key in this table, as determined by the
967		*         {@code equals} method; {@code false} otherwise
968		* @throws NullPointerException if the specified key is null
969		*/
970		public boolean containsKey(Object key) {
971	<	if (key == null)
2390	<	throw new NullPointerException();
2391	<	return internalGet(key) != null;
971	>	return get(key) != null;
972		}
973
974		/**
#	Line 2404 | Line 984 | public class ConcurrentHashMapV8<K, V>
984		public boolean containsValue(Object value) {
985		if (value == null)
986		throw new NullPointerException();
987	<	Object v;
988	<	InternalIterator<K,V> it = new InternalIterator<K,V>(this);
989	<	while ((v = it.advance()) != null) {
990	<	if (v == value || value.equals(v))
991	<	return true;
987	>	Node<K,V>[] t;
988	>	if ((t = table) != null) {
989	>	Traverser<K,V> it = new Traverser<K,V>(t, t.length, 0, t.length);
990	>	for (Node<K,V> p; (p = it.advance()) != null; ) {
991	>	V v;
992	>	if ((v = p.val) == value || (v != null && value.equals(v)))
993	>	return true;
994	>	}
995		}
996		return false;
997		}
998
999		/**
2417	–	* Legacy method testing if some key maps into the specified value
2418	–	* in this table.  This method is identical in functionality to
2419	–	* {@link #containsValue}, and exists solely to ensure
2420	–	* full compatibility with class {@link java.util.Hashtable},
2421	–	* which supported this method prior to introduction of the
2422	–	* Java Collections framework.
2423	–	*
2424	–	* @param  value a value to search for
2425	–	* @return {@code true} if and only if some key maps to the
2426	–	*         {@code value} argument in this table as
2427	–	*         determined by the {@code equals} method;
2428	–	*         {@code false} otherwise
2429	–	* @throws NullPointerException if the specified value is null
2430	–	*/
2431	–	public boolean contains(Object value) {
2432	–	return containsValue(value);
2433	–	}
2434	–
2435	–	/**
1000		* Maps the specified key to the specified value in this table.
1001		* Neither the key nor the value can be null.
1002		*
1003	<	* <p> The value can be retrieved by calling the {@code get} method
1003	>	* <p>The value can be retrieved by calling the {@code get} method
1004		* with a key that is equal to the original key.
1005		*
1006		* @param key key with which the specified value is to be associated
#	Line 2445 | Line 1009 | public class ConcurrentHashMapV8<K, V>
1009		*         {@code null} if there was no mapping for {@code key}
1010		* @throws NullPointerException if the specified key or value is null
1011		*/
2448	–	@SuppressWarnings("unchecked")
1012		public V put(K key, V value) {
1013	<	if (key == null || value == null)
2451	<	throw new NullPointerException();
2452	<	return (V)internalPut(key, value);
1013	>	return putVal(key, value, false);
1014		}
1015
1016	<	/**
1017	<	* {@inheritDoc}
1018	<	*
1019	<	* @return the previous value associated with the specified key,
1020	<	*         or {@code null} if there was no mapping for the key
1021	<	* @throws NullPointerException if the specified key or value is null
1022	<	*/
1023	<	@SuppressWarnings("unchecked")
1024	<	public V putIfAbsent(K key, V value) {
1025	<	if (key == null || value == null)
1026	<	throw new NullPointerException();
1027	<	return (V)internalPutIfAbsent(key, value);
1016	>	/** Implementation for put and putIfAbsent */
1017	>	final V putVal(K key, V value, boolean onlyIfAbsent) {
1018	>	if (key == null || value == null) throw new NullPointerException();
1019	>	int hash = spread(key.hashCode());
1020	>	int binCount = 0;
1021	>	for (Node<K,V>[] tab = table;;) {
1022	>	Node<K,V> f; int n, i, fh;
1023	>	if (tab == null || (n = tab.length) == 0)
1024	>	tab = initTable();
1025	>	else if ((f = tabAt(tab, i = (n - 1) & hash)) == null) {
1026	>	if (casTabAt(tab, i, null,
1027	>	new Node<K,V>(hash, key, value, null)))
1028	>	break;                   // no lock when adding to empty bin
1029	>	}
1030	>	else if ((fh = f.hash) == MOVED)
1031	>	tab = helpTransfer(tab, f);
1032	>	else {
1033	>	V oldVal = null;
1034	>	synchronized (f) {
1035	>	if (tabAt(tab, i) == f) {
1036	>	if (fh >= 0) {
1037	>	binCount = 1;
1038	>	for (Node<K,V> e = f;; ++binCount) {
1039	>	K ek;
1040	>	if (e.hash == hash &&
1041	>	((ek = e.key) == key ||
1042	>	(ek != null && key.equals(ek)))) {
1043	>	oldVal = e.val;
1044	>	if (!onlyIfAbsent)
1045	>	e.val = value;
1046	>	break;
1047	>	}
1048	>	Node<K,V> pred = e;
1049	>	if ((e = e.next) == null) {
1050	>	pred.next = new Node<K,V>(hash, key,
1051	>	value, null);
1052	>	break;
1053	>	}
1054	>	}
1055	>	}
1056	>	else if (f instanceof TreeBin) {
1057	>	Node<K,V> p;
1058	>	binCount = 2;
1059	>	if ((p = ((TreeBin<K,V>)f).putTreeVal(hash, key,
1060	>	value)) != null) {
1061	>	oldVal = p.val;
1062	>	if (!onlyIfAbsent)
1063	>	p.val = value;
1064	>	}
1065	>	}
1066	>	}
1067	>	}
1068	>	if (binCount != 0) {
1069	>	if (binCount >= TREEIFY_THRESHOLD)
1070	>	treeifyBin(tab, i);
1071	>	if (oldVal != null)
1072	>	return oldVal;
1073	>	break;
1074	>	}
1075	>	}
1076	>	}
1077	>	addCount(1L, binCount);
1078	>	return null;
1079		}
1080
1081		/**
#	Line 2474 | Line 1086 | public class ConcurrentHashMapV8<K, V>
1086		* @param m mappings to be stored in this map
1087		*/
1088		public void putAll(Map<? extends K, ? extends V> m) {
1089	<	internalPutAll(m);
1090	<	}
1091	<
2480	<	/**
2481	<	* If the specified key is not already associated with a value,
2482	<	* computes its value using the given mappingFunction and enters
2483	<	* it into the map unless null.  This is equivalent to
2484	<	* <pre> {@code
2485	<	* if (map.containsKey(key))
2486	<	*   return map.get(key);
2487	<	* value = mappingFunction.map(key);
2488	<	* if (value != null)
2489	<	*   map.put(key, value);
2490	<	* return value;}</pre>
2491	<	*
2492	<	* except that the action is performed atomically.  If the
2493	<	* function returns {@code null} no mapping is recorded. If the
2494	<	* function itself throws an (unchecked) exception, the exception
2495	<	* is rethrown to its caller, and no mapping is recorded.  Some
2496	<	* attempted update operations on this map by other threads may be
2497	<	* blocked while computation is in progress, so the computation
2498	<	* should be short and simple, and must not attempt to update any
2499	<	* other mappings of this Map. The most appropriate usage is to
2500	<	* construct a new object serving as an initial mapped value, or
2501	<	* memoized result, as in:
2502	<	*
2503	<	*  <pre> {@code
2504	<	* map.computeIfAbsent(key, new MappingFunction<K, V>() {
2505	<	*   public V map(K k) { return new Value(f(k)); }});}</pre>
2506	<	*
2507	<	* @param key key with which the specified value is to be associated
2508	<	* @param mappingFunction the function to compute a value
2509	<	* @return the current (existing or computed) value associated with
2510	<	*         the specified key, or null if the computed value is null.
2511	<	* @throws NullPointerException if the specified key or mappingFunction
2512	<	*         is null
2513	<	* @throws IllegalStateException if the computation detectably
2514	<	*         attempts a recursive update to this map that would
2515	<	*         otherwise never complete
2516	<	* @throws RuntimeException or Error if the mappingFunction does so,
2517	<	*         in which case the mapping is left unestablished
2518	<	*/
2519	<	@SuppressWarnings("unchecked")
2520	<	public V computeIfAbsent(K key, MappingFunction<? super K, ? extends V> mappingFunction) {
2521	<	if (key == null || mappingFunction == null)
2522	<	throw new NullPointerException();
2523	<	return (V)internalComputeIfAbsent(key, mappingFunction);
2524	<	}
2525	<
2526	<	/**
2527	<	* Computes a new mapping value given a key and
2528	<	* its current mapped value (or {@code null} if there is no current
2529	<	* mapping). This is equivalent to
2530	<	*  <pre> {@code
2531	<	*   value = remappingFunction.remap(key, map.get(key));
2532	<	*   if (value != null)
2533	<	*     map.put(key, value);
2534	<	*   else
2535	<	*     map.remove(key);
2536	<	* }</pre>
2537	<	*
2538	<	* except that the action is performed atomically.  If the
2539	<	* function returns {@code null}, the mapping is removed.  If the
2540	<	* function itself throws an (unchecked) exception, the exception
2541	<	* is rethrown to its caller, and the current mapping is left
2542	<	* unchanged.  Some attempted update operations on this map by
2543	<	* other threads may be blocked while computation is in progress,
2544	<	* so the computation should be short and simple, and must not
2545	<	* attempt to update any other mappings of this Map. For example,
2546	<	* to either create or append new messages to a value mapping:
2547	<	*
2548	<	* <pre> {@code
2549	<	* Map<Key, String> map = ...;
2550	<	* final String msg = ...;
2551	<	* map.compute(key, new RemappingFunction<Key, String>() {
2552	<	*   public String remap(Key k, String v) {
2553	<	*    return (v == null) ? msg : v + msg;});}}</pre>
2554	<	*
2555	<	* @param key key with which the specified value is to be associated
2556	<	* @param remappingFunction the function to compute a value
2557	<	* @return the new value associated with
2558	<	*         the specified key, or null if none.
2559	<	* @throws NullPointerException if the specified key or remappingFunction
2560	<	*         is null
2561	<	* @throws IllegalStateException if the computation detectably
2562	<	*         attempts a recursive update to this map that would
2563	<	*         otherwise never complete
2564	<	* @throws RuntimeException or Error if the remappingFunction does so,
2565	<	*         in which case the mapping is unchanged
2566	<	*/
2567	<	@SuppressWarnings("unchecked")
2568	<	public V compute(K key, RemappingFunction<? super K, V> remappingFunction) {
2569	<	if (key == null || remappingFunction == null)
2570	<	throw new NullPointerException();
2571	<	return (V)internalCompute(key, remappingFunction);
1089	>	tryPresize(m.size());
1090	>	for (Map.Entry<? extends K, ? extends V> e : m.entrySet())
1091	>	putVal(e.getKey(), e.getValue(), false);
1092		}
1093
1094		/**
#	Line 2580 | Line 1100 | public class ConcurrentHashMapV8<K, V>
1100		*         {@code null} if there was no mapping for {@code key}
1101		* @throws NullPointerException if the specified key is null
1102		*/
2583	–	@SuppressWarnings("unchecked")
1103		public V remove(Object key) {
1104	<	if (key == null)
2586	<	throw new NullPointerException();
2587	<	return (V)internalReplace(key, null, null);
1104	>	return replaceNode(key, null, null);
1105		}
1106
1107		/**
1108	<	* {@inheritDoc}
1109	<	*
1110	<	* @throws NullPointerException if the specified key is null
2594	<	*/
2595	<	public boolean remove(Object key, Object value) {
2596	<	if (key == null)
2597	<	throw new NullPointerException();
2598	<	if (value == null)
2599	<	return false;
2600	<	return internalReplace(key, null, value) != null;
2601	<	}
2602	<
2603	<	/**
2604	<	* {@inheritDoc}
2605	<	*
2606	<	* @throws NullPointerException if any of the arguments are null
2607	<	*/
2608	<	public boolean replace(K key, V oldValue, V newValue) {
2609	<	if (key == null || oldValue == null || newValue == null)
2610	<	throw new NullPointerException();
2611	<	return internalReplace(key, newValue, oldValue) != null;
2612	<	}
2613	<
2614	<	/**
2615	<	* {@inheritDoc}
2616	<	*
2617	<	* @return the previous value associated with the specified key,
2618	<	*         or {@code null} if there was no mapping for the key
2619	<	* @throws NullPointerException if the specified key or value is null
1108	>	* Implementation for the four public remove/replace methods:
1109	>	* Replaces node value with v, conditional upon match of cv if
1110	>	* non-null.  If resulting value is null, delete.
1111		*/
1112	<	@SuppressWarnings("unchecked")
1113	<	public V replace(K key, V value) {
1114	<	if (key == null || value == null)
1115	<	throw new NullPointerException();
1116	<	return (V)internalReplace(key, value, null);
1112	>	final V replaceNode(Object key, V value, Object cv) {
1113	>	int hash = spread(key.hashCode());
1114	>	for (Node<K,V>[] tab = table;;) {
1115	>	Node<K,V> f; int n, i, fh;
1116	>	if (tab == null || (n = tab.length) == 0 ||
1117	>	(f = tabAt(tab, i = (n - 1) & hash)) == null)
1118	>	break;
1119	>	else if ((fh = f.hash) == MOVED)
1120	>	tab = helpTransfer(tab, f);
1121	>	else {
1122	>	V oldVal = null;
1123	>	boolean validated = false;
1124	>	synchronized (f) {
1125	>	if (tabAt(tab, i) == f) {
1126	>	if (fh >= 0) {
1127	>	validated = true;
1128	>	for (Node<K,V> e = f, pred = null;;) {
1129	>	K ek;
1130	>	if (e.hash == hash &&
1131	>	((ek = e.key) == key ||
1132	>	(ek != null && key.equals(ek)))) {
1133	>	V ev = e.val;
1134	>	if (cv == null || cv == ev ||
1135	>	(ev != null && cv.equals(ev))) {
1136	>	oldVal = ev;
1137	>	if (value != null)
1138	>	e.val = value;
1139	>	else if (pred != null)
1140	>	pred.next = e.next;
1141	>	else
1142	>	setTabAt(tab, i, e.next);
1143	>	}
1144	>	break;
1145	>	}
1146	>	pred = e;
1147	>	if ((e = e.next) == null)
1148	>	break;
1149	>	}
1150	>	}
1151	>	else if (f instanceof TreeBin) {
1152	>	validated = true;
1153	>	TreeBin<K,V> t = (TreeBin<K,V>)f;
1154	>	TreeNode<K,V> r, p;
1155	>	if ((r = t.root) != null &&
1156	>	(p = r.findTreeNode(hash, key, null)) != null) {
1157	>	V pv = p.val;
1158	>	if (cv == null || cv == pv ||
1159	>	(pv != null && cv.equals(pv))) {
1160	>	oldVal = pv;
1161	>	if (value != null)
1162	>	p.val = value;
1163	>	else if (t.removeTreeNode(p))
1164	>	setTabAt(tab, i, untreeify(t.first));
1165	>	}
1166	>	}
1167	>	}
1168	>	}
1169	>	}
1170	>	if (validated) {
1171	>	if (oldVal != null) {
1172	>	if (value == null)
1173	>	addCount(-1L, -1);
1174	>	return oldVal;
1175	>	}
1176	>	break;
1177	>	}
1178	>	}
1179	>	}
1180	>	return null;
1181		}
1182
1183		/**
1184		* Removes all of the mappings from this map.
1185		*/
1186		public void clear() {
1187	<	internalClear();
1187	>	long delta = 0L; // negative number of deletions
1188	>	int i = 0;
1189	>	Node<K,V>[] tab = table;
1190	>	while (tab != null && i < tab.length) {
1191	>	int fh;
1192	>	Node<K,V> f = tabAt(tab, i);
1193	>	if (f == null)
1194	>	++i;
1195	>	else if ((fh = f.hash) == MOVED) {
1196	>	tab = helpTransfer(tab, f);
1197	>	i = 0; // restart
1198	>	}
1199	>	else {
1200	>	synchronized (f) {
1201	>	if (tabAt(tab, i) == f) {
1202	>	Node<K,V> p = (fh >= 0 ? f :
1203	>	(f instanceof TreeBin) ?
1204	>	((TreeBin<K,V>)f).first : null);
1205	>	while (p != null) {
1206	>	--delta;
1207	>	p = p.next;
1208	>	}
1209	>	setTabAt(tab, i++, null);
1210	>	}
1211	>	}
1212	>	}
1213	>	}
1214	>	if (delta != 0L)
1215	>	addCount(delta, -1);
1216		}
1217
1218		/**
1219		* Returns a {@link Set} view of the keys contained in this map.
1220		* The set is backed by the map, so changes to the map are
1221	<	* reflected in the set, and vice-versa.  The set supports element
1221	>	* reflected in the set, and vice-versa. The set supports element
1222		* removal, which removes the corresponding mapping from this map,
1223		* via the {@code Iterator.remove}, {@code Set.remove},
1224		* {@code removeAll}, {@code retainAll}, and {@code clear}
#	Line 2647 | Line 1230 | public class ConcurrentHashMapV8<K, V>
1230		* and guarantees to traverse elements as they existed upon
1231		* construction of the iterator, and may (but is not guaranteed to)
1232		* reflect any modifications subsequent to construction.
1233	+	*
1234	+	* @return the set view
1235		*/
1236	<	public Set<K> keySet() {
1237	<	KeySet<K,V> ks = keySet;
1238	<	return (ks != null) ? ks : (keySet = new KeySet<K,V>(this));
1236	>	public KeySetView<K,V> keySet() {
1237	>	KeySetView<K,V> ks;
1238	>	return (ks = keySet) != null ? ks : (keySet = new KeySetView<K,V>(this, null));
1239		}
1240
1241		/**
#	Line 2668 | Line 1253 | public class ConcurrentHashMapV8<K, V>
1253		* and guarantees to traverse elements as they existed upon
1254		* construction of the iterator, and may (but is not guaranteed to)
1255		* reflect any modifications subsequent to construction.
1256	+	*
1257	+	* @return the collection view
1258		*/
1259		public Collection<V> values() {
1260	<	Values<K,V> vs = values;
1261	<	return (vs != null) ? vs : (values = new Values<K,V>(this));
1260	>	ValuesView<K,V> vs;
1261	>	return (vs = values) != null ? vs : (values = new ValuesView<K,V>(this));
1262		}
1263
1264		/**
#	Line 2681 | Line 1268 | public class ConcurrentHashMapV8<K, V>
1268		* removal, which removes the corresponding mapping from the map,
1269		* via the {@code Iterator.remove}, {@code Set.remove},
1270		* {@code removeAll}, {@code retainAll}, and {@code clear}
1271	<	* operations.  It does not support the {@code add} or
2685	<	* {@code addAll} operations.
1271	>	* operations.
1272		*
1273		* <p>The view's {@code iterator} is a "weakly consistent" iterator
1274		* that will never throw {@link ConcurrentModificationException},
1275		* and guarantees to traverse elements as they existed upon
1276		* construction of the iterator, and may (but is not guaranteed to)
1277		* reflect any modifications subsequent to construction.
2692	–	*/
2693	–	public Set<Map.Entry<K,V>> entrySet() {
2694	–	EntrySet<K,V> es = entrySet;
2695	–	return (es != null) ? es : (entrySet = new EntrySet<K,V>(this));
2696	–	}
2697	–
2698	–	/**
2699	–	* Returns an enumeration of the keys in this table.
2700	–	*
2701	–	* @return an enumeration of the keys in this table
2702	–	* @see #keySet()
2703	–	*/
2704	–	public Enumeration<K> keys() {
2705	–	return new KeyIterator<K,V>(this);
2706	–	}
2707	–
2708	–	/**
2709	–	* Returns an enumeration of the values in this table.
2710	–	*
2711	–	* @return an enumeration of the values in this table
2712	–	* @see #values()
2713	–	*/
2714	–	public Enumeration<V> elements() {
2715	–	return new ValueIterator<K,V>(this);
2716	–	}
2717	–
2718	–	/**
2719	–	* Returns a partionable iterator of the keys in this map.
2720	–	*
2721	–	* @return a partionable iterator of the keys in this map
2722	–	*/
2723	–	public Spliterator<K> keySpliterator() {
2724	–	return new KeyIterator<K,V>(this);
2725	–	}
2726	–
2727	–	/**
2728	–	* Returns a partionable iterator of the values in this map.
1278		*
1279	<	* @return a partionable iterator of the values in this map
1279	>	* @return the set view
1280		*/
1281	<	public Spliterator<V> valueSpliterator() {
1282	<	return new ValueIterator<K,V>(this);
1283	<	}
2735	<
2736	<	/**
2737	<	* Returns a partionable iterator of the entries in this map.
2738	<	*
2739	<	* @return a partionable iterator of the entries in this map
2740	<	*/
2741	<	public Spliterator<Map.Entry<K,V>> entrySpliterator() {
2742	<	return new EntryIterator<K,V>(this);
1281	>	public Set<Map.Entry<K,V>> entrySet() {
1282	>	EntrySetView<K,V> es;
1283	>	return (es = entrySet) != null ? es : (entrySet = new EntrySetView<K,V>(this));
1284		}
1285
1286		/**
#	Line 2751 | Line 1292 | public class ConcurrentHashMapV8<K, V>
1292		*/
1293		public int hashCode() {
1294		int h = 0;
1295	<	InternalIterator<K,V> it = new InternalIterator<K,V>(this);
1296	<	Object v;
1297	<	while ((v = it.advance()) != null) {
1298	<	h += it.nextKey.hashCode() ^ v.hashCode();
1295	>	Node<K,V>[] t;
1296	>	if ((t = table) != null) {
1297	>	Traverser<K,V> it = new Traverser<K,V>(t, t.length, 0, t.length);
1298	>	for (Node<K,V> p; (p = it.advance()) != null; )
1299	>	h += p.key.hashCode() ^ p.val.hashCode();
1300		}
1301		return h;
1302		}
#	Line 2771 | Line 1313 | public class ConcurrentHashMapV8<K, V>
1313		* @return a string representation of this map
1314		*/
1315		public String toString() {
1316	<	InternalIterator<K,V> it = new InternalIterator<K,V>(this);
1316	>	Node<K,V>[] t;
1317	>	int f = (t = table) == null ? 0 : t.length;
1318	>	Traverser<K,V> it = new Traverser<K,V>(t, f, 0, f);
1319		StringBuilder sb = new StringBuilder();
1320		sb.append('{');
1321	<	Object v;
1322	<	if ((v = it.advance()) != null) {
1321	>	Node<K,V> p;
1322	>	if ((p = it.advance()) != null) {
1323		for (;;) {
1324	<	Object k = it.nextKey;
1324	>	K k = p.key;
1325	>	V v = p.val;
1326		sb.append(k == this ? "(this Map)" : k);
1327		sb.append('=');
1328		sb.append(v == this ? "(this Map)" : v);
1329	<	if ((v = it.advance()) == null)
1329	>	if ((p = it.advance()) == null)
1330		break;
1331		sb.append(',').append(' ');
1332		}
#	Line 2804 | Line 1349 | public class ConcurrentHashMapV8<K, V>
1349		if (!(o instanceof Map))
1350		return false;
1351		Map<?,?> m = (Map<?,?>) o;
1352	<	InternalIterator<K,V> it = new InternalIterator<K,V>(this);
1353	<	Object val;
1354	<	while ((val = it.advance()) != null) {
1355	<	Object v = m.get(it.nextKey);
1352	>	Node<K,V>[] t;
1353	>	int f = (t = table) == null ? 0 : t.length;
1354	>	Traverser<K,V> it = new Traverser<K,V>(t, f, 0, f);
1355	>	for (Node<K,V> p; (p = it.advance()) != null; ) {
1356	>	V val = p.val;
1357	>	Object v = m.get(p.key);
1358		if (v == null || (v != val && !v.equals(val)))
1359		return false;
1360		}
#	Line 2815 | Line 1362 | public class ConcurrentHashMapV8<K, V>
1362		Object mk, mv, v;
1363		if ((mk = e.getKey()) == null ||
1364		(mv = e.getValue()) == null ||
1365	<	(v = internalGet(mk)) == null ||
1365	>	(v = get(mk)) == null ||
1366		(mv != v && !mv.equals(v)))
1367		return false;
1368		}
#	Line 2823 | Line 1370 | public class ConcurrentHashMapV8<K, V>
1370		return true;
1371		}
1372
1373	<	/* ----------------Iterators -------------- */
1373	>	/**
1374	>	* Stripped-down version of helper class used in previous version,
1375	>	* declared for the sake of serialization compatibility
1376	>	*/
1377	>	static class Segment<K,V> extends ReentrantLock implements Serializable {
1378	>	private static final long serialVersionUID = 2249069246763182397L;
1379	>	final float loadFactor;
1380	>	Segment(float lf) { this.loadFactor = lf; }
1381	>	}
1382
1383	<	static final class KeyIterator<K,V> extends InternalIterator<K,V>
1384	<	implements Spliterator<K>, Enumeration<K> {
1385	<	KeyIterator(ConcurrentHashMapV8<K, V> map) { super(map); }
1386	<	KeyIterator(InternalIterator<K,V> it, boolean split) {
1387	<	super(it, split);
1383	>	/**
1384	>	* Saves the state of the {@code ConcurrentHashMapV8} instance to a
1385	>	* stream (i.e., serializes it).
1386	>	* @param s the stream
1387	>	* @throws java.io.IOException if an I/O error occurs
1388	>	* @serialData
1389	>	* the key (Object) and value (Object)
1390	>	* for each key-value mapping, followed by a null pair.
1391	>	* The key-value mappings are emitted in no particular order.
1392	>	*/
1393	>	private void writeObject(java.io.ObjectOutputStream s)
1394	>	throws java.io.IOException {
1395	>	// For serialization compatibility
1396	>	// Emulate segment calculation from previous version of this class
1397	>	int sshift = 0;
1398	>	int ssize = 1;
1399	>	while (ssize < DEFAULT_CONCURRENCY_LEVEL) {
1400	>	++sshift;
1401	>	ssize <<= 1;
1402	>	}
1403	>	int segmentShift = 32 - sshift;
1404	>	int segmentMask = ssize - 1;
1405	>	@SuppressWarnings("unchecked") Segment<K,V>[] segments = (Segment<K,V>[])
1406	>	new Segment<?,?>[DEFAULT_CONCURRENCY_LEVEL];
1407	>	for (int i = 0; i < segments.length; ++i)
1408	>	segments[i] = new Segment<K,V>(LOAD_FACTOR);
1409	>	s.putFields().put("segments", segments);
1410	>	s.putFields().put("segmentShift", segmentShift);
1411	>	s.putFields().put("segmentMask", segmentMask);
1412	>	s.writeFields();
1413	>
1414	>	Node<K,V>[] t;
1415	>	if ((t = table) != null) {
1416	>	Traverser<K,V> it = new Traverser<K,V>(t, t.length, 0, t.length);
1417	>	for (Node<K,V> p; (p = it.advance()) != null; ) {
1418	>	s.writeObject(p.key);
1419	>	s.writeObject(p.val);
1420	>	}
1421		}
1422	<	public KeyIterator<K,V> split() {
1423	<	if (last != null || (next != null && nextVal == null))
1424	<	throw new IllegalStateException();
1425	<	return new KeyIterator<K,V>(this, true);
1422	>	s.writeObject(null);
1423	>	s.writeObject(null);
1424	>	segments = null; // throw away
1425	>	}
1426	>
1427	>	/**
1428	>	* Reconstitutes the instance from a stream (that is, deserializes it).
1429	>	* @param s the stream
1430	>	* @throws ClassNotFoundException if the class of a serialized object
1431	>	*         could not be found
1432	>	* @throws java.io.IOException if an I/O error occurs
1433	>	*/
1434	>	private void readObject(java.io.ObjectInputStream s)
1435	>	throws java.io.IOException, ClassNotFoundException {
1436	>	/*
1437	>	* To improve performance in typical cases, we create nodes
1438	>	* while reading, then place in table once size is known.
1439	>	* However, we must also validate uniqueness and deal with
1440	>	* overpopulated bins while doing so, which requires
1441	>	* specialized versions of putVal mechanics.
1442	>	*/
1443	>	sizeCtl = -1; // force exclusion for table construction
1444	>	s.defaultReadObject();
1445	>	long size = 0L;
1446	>	Node<K,V> p = null;
1447	>	for (;;) {
1448	>	@SuppressWarnings("unchecked") K k = (K) s.readObject();
1449	>	@SuppressWarnings("unchecked") V v = (V) s.readObject();
1450	>	if (k != null && v != null) {
1451	>	p = new Node<K,V>(spread(k.hashCode()), k, v, p);
1452	>	++size;
1453	>	}
1454	>	else
1455	>	break;
1456		}
1457	<	public KeyIterator<K,V> clone() {
1458	<	if (last != null || (next != null && nextVal == null))
1459	<	throw new IllegalStateException();
1460	<	return new KeyIterator<K,V>(this, false);
1457	>	if (size == 0L)
1458	>	sizeCtl = 0;
1459	>	else {
1460	>	int n;
1461	>	if (size >= (long)(MAXIMUM_CAPACITY >>> 1))
1462	>	n = MAXIMUM_CAPACITY;
1463	>	else {
1464	>	int sz = (int)size;
1465	>	n = tableSizeFor(sz + (sz >>> 1) + 1);
1466	>	}
1467	>	@SuppressWarnings("unchecked")
1468	>	Node<K,V>[] tab = (Node<K,V>[])new Node<?,?>[n];
1469	>	int mask = n - 1;
1470	>	long added = 0L;
1471	>	while (p != null) {
1472	>	boolean insertAtFront;
1473	>	Node<K,V> next = p.next, first;
1474	>	int h = p.hash, j = h & mask;
1475	>	if ((first = tabAt(tab, j)) == null)
1476	>	insertAtFront = true;
1477	>	else {
1478	>	K k = p.key;
1479	>	if (first.hash < 0) {
1480	>	TreeBin<K,V> t = (TreeBin<K,V>)first;
1481	>	if (t.putTreeVal(h, k, p.val) == null)
1482	>	++added;
1483	>	insertAtFront = false;
1484	>	}
1485	>	else {
1486	>	int binCount = 0;
1487	>	insertAtFront = true;
1488	>	Node<K,V> q; K qk;
1489	>	for (q = first; q != null; q = q.next) {
1490	>	if (q.hash == h &&
1491	>	((qk = q.key) == k ||
1492	>	(qk != null && k.equals(qk)))) {
1493	>	insertAtFront = false;
1494	>	break;
1495	>	}
1496	>	++binCount;
1497	>	}
1498	>	if (insertAtFront && binCount >= TREEIFY_THRESHOLD) {
1499	>	insertAtFront = false;
1500	>	++added;
1501	>	p.next = first;
1502	>	TreeNode<K,V> hd = null, tl = null;
1503	>	for (q = p; q != null; q = q.next) {
1504	>	TreeNode<K,V> t = new TreeNode<K,V>
1505	>	(q.hash, q.key, q.val, null, null);
1506	>	if ((t.prev = tl) == null)
1507	>	hd = t;
1508	>	else
1509	>	tl.next = t;
1510	>	tl = t;
1511	>	}
1512	>	setTabAt(tab, j, new TreeBin<K,V>(hd));
1513	>	}
1514	>	}
1515	>	}
1516	>	if (insertAtFront) {
1517	>	++added;
1518	>	p.next = first;
1519	>	setTabAt(tab, j, p);
1520	>	}
1521	>	p = next;
1522	>	}
1523	>	table = tab;
1524	>	sizeCtl = n - (n >>> 2);
1525	>	baseCount = added;
1526		}
1527	+	}
1528
1529	<	@SuppressWarnings("unchecked")
1530	<	public final K next() {
1531	<	if (nextVal == null && advance() == null)
1532	<	throw new NoSuchElementException();
1533	<	Object k = nextKey;
1534	<	nextVal = null;
1535	<	return (K) k;
1529	>	// ConcurrentMap methods
1530	>
1531	>	/**
1532	>	* {@inheritDoc}
1533	>	*
1534	>	* @return the previous value associated with the specified key,
1535	>	*         or {@code null} if there was no mapping for the key
1536	>	* @throws NullPointerException if the specified key or value is null
1537	>	*/
1538	>	public V putIfAbsent(K key, V value) {
1539	>	return putVal(key, value, true);
1540	>	}
1541	>
1542	>	/**
1543	>	* {@inheritDoc}
1544	>	*
1545	>	* @throws NullPointerException if the specified key is null
1546	>	*/
1547	>	public boolean remove(Object key, Object value) {
1548	>	if (key == null)
1549	>	throw new NullPointerException();
1550	>	return value != null && replaceNode(key, null, value) != null;
1551	>	}
1552	>
1553	>	/**
1554	>	* {@inheritDoc}
1555	>	*
1556	>	* @throws NullPointerException if any of the arguments are null
1557	>	*/
1558	>	public boolean replace(K key, V oldValue, V newValue) {
1559	>	if (key == null || oldValue == null || newValue == null)
1560	>	throw new NullPointerException();
1561	>	return replaceNode(key, newValue, oldValue) != null;
1562	>	}
1563	>
1564	>	/**
1565	>	* {@inheritDoc}
1566	>	*
1567	>	* @return the previous value associated with the specified key,
1568	>	*         or {@code null} if there was no mapping for the key
1569	>	* @throws NullPointerException if the specified key or value is null
1570	>	*/
1571	>	public V replace(K key, V value) {
1572	>	if (key == null || value == null)
1573	>	throw new NullPointerException();
1574	>	return replaceNode(key, value, null);
1575	>	}
1576	>
1577	>	// Overrides of JDK8+ Map extension method defaults
1578	>
1579	>	/**
1580	>	* Returns the value to which the specified key is mapped, or the
1581	>	* given default value if this map contains no mapping for the
1582	>	* key.
1583	>	*
1584	>	* @param key the key whose associated value is to be returned
1585	>	* @param defaultValue the value to return if this map contains
1586	>	* no mapping for the given key
1587	>	* @return the mapping for the key, if present; else the default value
1588	>	* @throws NullPointerException if the specified key is null
1589	>	*/
1590	>	public V getOrDefault(Object key, V defaultValue) {
1591	>	V v;
1592	>	return (v = get(key)) == null ? defaultValue : v;
1593	>	}
1594	>
1595	>	public void forEach(BiAction<? super K, ? super V> action) {
1596	>	if (action == null) throw new NullPointerException();
1597	>	Node<K,V>[] t;
1598	>	if ((t = table) != null) {
1599	>	Traverser<K,V> it = new Traverser<K,V>(t, t.length, 0, t.length);
1600	>	for (Node<K,V> p; (p = it.advance()) != null; ) {
1601	>	action.apply(p.key, p.val);
1602	>	}
1603		}
1604	+	}
1605
1606	<	public final K nextElement() { return next(); }
1606	>	public void replaceAll(BiFun<? super K, ? super V, ? extends V> function) {
1607	>	if (function == null) throw new NullPointerException();
1608	>	Node<K,V>[] t;
1609	>	if ((t = table) != null) {
1610	>	Traverser<K,V> it = new Traverser<K,V>(t, t.length, 0, t.length);
1611	>	for (Node<K,V> p; (p = it.advance()) != null; ) {
1612	>	V oldValue = p.val;
1613	>	for (K key = p.key;;) {
1614	>	V newValue = function.apply(key, oldValue);
1615	>	if (newValue == null)
1616	>	throw new NullPointerException();
1617	>	if (replaceNode(key, newValue, oldValue) != null ||
1618	>	(oldValue = get(key)) == null)
1619	>	break;
1620	>	}
1621	>	}
1622	>	}
1623		}
1624
1625	<	static final class ValueIterator<K,V> extends InternalIterator<K,V>
1626	<	implements Spliterator<V>, Enumeration<V> {
1627	<	ValueIterator(ConcurrentHashMapV8<K, V> map) { super(map); }
1628	<	ValueIterator(InternalIterator<K,V> it, boolean split) {
1629	<	super(it, split);
1625	>	/**
1626	>	* If the specified key is not already associated with a value,
1627	>	* attempts to compute its value using the given mapping function
1628	>	* and enters it into this map unless {@code null}.  The entire
1629	>	* method invocation is performed atomically, so the function is
1630	>	* applied at most once per key.  Some attempted update operations
1631	>	* on this map by other threads may be blocked while computation
1632	>	* is in progress, so the computation should be short and simple,
1633	>	* and must not attempt to update any other mappings of this map.
1634	>	*
1635	>	* @param key key with which the specified value is to be associated
1636	>	* @param mappingFunction the function to compute a value
1637	>	* @return the current (existing or computed) value associated with
1638	>	*         the specified key, or null if the computed value is null
1639	>	* @throws NullPointerException if the specified key or mappingFunction
1640	>	*         is null
1641	>	* @throws IllegalStateException if the computation detectably
1642	>	*         attempts a recursive update to this map that would
1643	>	*         otherwise never complete
1644	>	* @throws RuntimeException or Error if the mappingFunction does so,
1645	>	*         in which case the mapping is left unestablished
1646	>	*/
1647	>	public V computeIfAbsent(K key, Fun<? super K, ? extends V> mappingFunction) {
1648	>	if (key == null || mappingFunction == null)
1649	>	throw new NullPointerException();
1650	>	int h = spread(key.hashCode());
1651	>	V val = null;
1652	>	int binCount = 0;
1653	>	for (Node<K,V>[] tab = table;;) {
1654	>	Node<K,V> f; int n, i, fh;
1655	>	if (tab == null || (n = tab.length) == 0)
1656	>	tab = initTable();
1657	>	else if ((f = tabAt(tab, i = (n - 1) & h)) == null) {
1658	>	Node<K,V> r = new ReservationNode<K,V>();
1659	>	synchronized (r) {
1660	>	if (casTabAt(tab, i, null, r)) {
1661	>	binCount = 1;
1662	>	Node<K,V> node = null;
1663	>	try {
1664	>	if ((val = mappingFunction.apply(key)) != null)
1665	>	node = new Node<K,V>(h, key, val, null);
1666	>	} finally {
1667	>	setTabAt(tab, i, node);
1668	>	}
1669	>	}
1670	>	}
1671	>	if (binCount != 0)
1672	>	break;
1673	>	}
1674	>	else if ((fh = f.hash) == MOVED)
1675	>	tab = helpTransfer(tab, f);
1676	>	else {
1677	>	boolean added = false;
1678	>	synchronized (f) {
1679	>	if (tabAt(tab, i) == f) {
1680	>	if (fh >= 0) {
1681	>	binCount = 1;
1682	>	for (Node<K,V> e = f;; ++binCount) {
1683	>	K ek; V ev;
1684	>	if (e.hash == h &&
1685	>	((ek = e.key) == key ||
1686	>	(ek != null && key.equals(ek)))) {
1687	>	val = e.val;
1688	>	break;
1689	>	}
1690	>	Node<K,V> pred = e;
1691	>	if ((e = e.next) == null) {
1692	>	if ((val = mappingFunction.apply(key)) != null) {
1693	>	added = true;
1694	>	pred.next = new Node<K,V>(h, key, val, null);
1695	>	}
1696	>	break;
1697	>	}
1698	>	}
1699	>	}
1700	>	else if (f instanceof TreeBin) {
1701	>	binCount = 2;
1702	>	TreeBin<K,V> t = (TreeBin<K,V>)f;
1703	>	TreeNode<K,V> r, p;
1704	>	if ((r = t.root) != null &&
1705	>	(p = r.findTreeNode(h, key, null)) != null)
1706	>	val = p.val;
1707	>	else if ((val = mappingFunction.apply(key)) != null) {
1708	>	added = true;
1709	>	t.putTreeVal(h, key, val);
1710	>	}
1711	>	}
1712	>	}
1713	>	}
1714	>	if (binCount != 0) {
1715	>	if (binCount >= TREEIFY_THRESHOLD)
1716	>	treeifyBin(tab, i);
1717	>	if (!added)
1718	>	return val;
1719	>	break;
1720	>	}
1721	>	}
1722		}
1723	<	public ValueIterator<K,V> split() {
1724	<	if (last != null || (next != null && nextVal == null))
1725	<	throw new IllegalStateException();
1726	<	return new ValueIterator<K,V>(this, true);
1723	>	if (val != null)
1724	>	addCount(1L, binCount);
1725	>	return val;
1726	>	}
1727	>
1728	>	/**
1729	>	* If the value for the specified key is present, attempts to
1730	>	* compute a new mapping given the key and its current mapped
1731	>	* value.  The entire method invocation is performed atomically.
1732	>	* Some attempted update operations on this map by other threads
1733	>	* may be blocked while computation is in progress, so the
1734	>	* computation should be short and simple, and must not attempt to
1735	>	* update any other mappings of this map.
1736	>	*
1737	>	* @param key key with which a value may be associated
1738	>	* @param remappingFunction the function to compute a value
1739	>	* @return the new value associated with the specified key, or null if none
1740	>	* @throws NullPointerException if the specified key or remappingFunction
1741	>	*         is null
1742	>	* @throws IllegalStateException if the computation detectably
1743	>	*         attempts a recursive update to this map that would
1744	>	*         otherwise never complete
1745	>	* @throws RuntimeException or Error if the remappingFunction does so,
1746	>	*         in which case the mapping is unchanged
1747	>	*/
1748	>	public V computeIfPresent(K key, BiFun<? super K, ? super V, ? extends V> remappingFunction) {
1749	>	if (key == null || remappingFunction == null)
1750	>	throw new NullPointerException();
1751	>	int h = spread(key.hashCode());
1752	>	V val = null;
1753	>	int delta = 0;
1754	>	int binCount = 0;
1755	>	for (Node<K,V>[] tab = table;;) {
1756	>	Node<K,V> f; int n, i, fh;
1757	>	if (tab == null || (n = tab.length) == 0)
1758	>	tab = initTable();
1759	>	else if ((f = tabAt(tab, i = (n - 1) & h)) == null)
1760	>	break;
1761	>	else if ((fh = f.hash) == MOVED)
1762	>	tab = helpTransfer(tab, f);
1763	>	else {
1764	>	synchronized (f) {
1765	>	if (tabAt(tab, i) == f) {
1766	>	if (fh >= 0) {
1767	>	binCount = 1;
1768	>	for (Node<K,V> e = f, pred = null;; ++binCount) {
1769	>	K ek;
1770	>	if (e.hash == h &&
1771	>	((ek = e.key) == key ||
1772	>	(ek != null && key.equals(ek)))) {
1773	>	val = remappingFunction.apply(key, e.val);
1774	>	if (val != null)
1775	>	e.val = val;
1776	>	else {
1777	>	delta = -1;
1778	>	Node<K,V> en = e.next;
1779	>	if (pred != null)
1780	>	pred.next = en;
1781	>	else
1782	>	setTabAt(tab, i, en);
1783	>	}
1784	>	break;
1785	>	}
1786	>	pred = e;
1787	>	if ((e = e.next) == null)
1788	>	break;
1789	>	}
1790	>	}
1791	>	else if (f instanceof TreeBin) {
1792	>	binCount = 2;
1793	>	TreeBin<K,V> t = (TreeBin<K,V>)f;
1794	>	TreeNode<K,V> r, p;
1795	>	if ((r = t.root) != null &&
1796	>	(p = r.findTreeNode(h, key, null)) != null) {
1797	>	val = remappingFunction.apply(key, p.val);
1798	>	if (val != null)
1799	>	p.val = val;
1800	>	else {
1801	>	delta = -1;
1802	>	if (t.removeTreeNode(p))
1803	>	setTabAt(tab, i, untreeify(t.first));
1804	>	}
1805	>	}
1806	>	}
1807	>	}
1808	>	}
1809	>	if (binCount != 0)
1810	>	break;
1811	>	}
1812		}
1813	+	if (delta != 0)
1814	+	addCount((long)delta, binCount);
1815	+	return val;
1816	+	}
1817
1818	<	public ValueIterator<K,V> clone() {
1819	<	if (last != null || (next != null && nextVal == null))
1818	>	/**
1819	>	* Attempts to compute a mapping for the specified key and its
1820	>	* current mapped value (or {@code null} if there is no current
1821	>	* mapping). The entire method invocation is performed atomically.
1822	>	* Some attempted update operations on this map by other threads
1823	>	* may be blocked while computation is in progress, so the
1824	>	* computation should be short and simple, and must not attempt to
1825	>	* update any other mappings of this Map.
1826	>	*
1827	>	* @param key key with which the specified value is to be associated
1828	>	* @param remappingFunction the function to compute a value
1829	>	* @return the new value associated with the specified key, or null if none
1830	>	* @throws NullPointerException if the specified key or remappingFunction
1831	>	*         is null
1832	>	* @throws IllegalStateException if the computation detectably
1833	>	*         attempts a recursive update to this map that would
1834	>	*         otherwise never complete
1835	>	* @throws RuntimeException or Error if the remappingFunction does so,
1836	>	*         in which case the mapping is unchanged
1837	>	*/
1838	>	public V compute(K key,
1839	>	BiFun<? super K, ? super V, ? extends V> remappingFunction) {
1840	>	if (key == null || remappingFunction == null)
1841	>	throw new NullPointerException();
1842	>	int h = spread(key.hashCode());
1843	>	V val = null;
1844	>	int delta = 0;
1845	>	int binCount = 0;
1846	>	for (Node<K,V>[] tab = table;;) {
1847	>	Node<K,V> f; int n, i, fh;
1848	>	if (tab == null || (n = tab.length) == 0)
1849	>	tab = initTable();
1850	>	else if ((f = tabAt(tab, i = (n - 1) & h)) == null) {
1851	>	Node<K,V> r = new ReservationNode<K,V>();
1852	>	synchronized (r) {
1853	>	if (casTabAt(tab, i, null, r)) {
1854	>	binCount = 1;
1855	>	Node<K,V> node = null;
1856	>	try {
1857	>	if ((val = remappingFunction.apply(key, null)) != null) {
1858	>	delta = 1;
1859	>	node = new Node<K,V>(h, key, val, null);
1860	>	}
1861	>	} finally {
1862	>	setTabAt(tab, i, node);
1863	>	}
1864	>	}
1865	>	}
1866	>	if (binCount != 0)
1867	>	break;
1868	>	}
1869	>	else if ((fh = f.hash) == MOVED)
1870	>	tab = helpTransfer(tab, f);
1871	>	else {
1872	>	synchronized (f) {
1873	>	if (tabAt(tab, i) == f) {
1874	>	if (fh >= 0) {
1875	>	binCount = 1;
1876	>	for (Node<K,V> e = f, pred = null;; ++binCount) {
1877	>	K ek;
1878	>	if (e.hash == h &&
1879	>	((ek = e.key) == key ||
1880	>	(ek != null && key.equals(ek)))) {
1881	>	val = remappingFunction.apply(key, e.val);
1882	>	if (val != null)
1883	>	e.val = val;
1884	>	else {
1885	>	delta = -1;
1886	>	Node<K,V> en = e.next;
1887	>	if (pred != null)
1888	>	pred.next = en;
1889	>	else
1890	>	setTabAt(tab, i, en);
1891	>	}
1892	>	break;
1893	>	}
1894	>	pred = e;
1895	>	if ((e = e.next) == null) {
1896	>	val = remappingFunction.apply(key, null);
1897	>	if (val != null) {
1898	>	delta = 1;
1899	>	pred.next =
1900	>	new Node<K,V>(h, key, val, null);
1901	>	}
1902	>	break;
1903	>	}
1904	>	}
1905	>	}
1906	>	else if (f instanceof TreeBin) {
1907	>	binCount = 1;
1908	>	TreeBin<K,V> t = (TreeBin<K,V>)f;
1909	>	TreeNode<K,V> r, p;
1910	>	if ((r = t.root) != null)
1911	>	p = r.findTreeNode(h, key, null);
1912	>	else
1913	>	p = null;
1914	>	V pv = (p == null) ? null : p.val;
1915	>	val = remappingFunction.apply(key, pv);
1916	>	if (val != null) {
1917	>	if (p != null)
1918	>	p.val = val;
1919	>	else {
1920	>	delta = 1;
1921	>	t.putTreeVal(h, key, val);
1922	>	}
1923	>	}
1924	>	else if (p != null) {
1925	>	delta = -1;
1926	>	if (t.removeTreeNode(p))
1927	>	setTabAt(tab, i, untreeify(t.first));
1928	>	}
1929	>	}
1930	>	}
1931	>	}
1932	>	if (binCount != 0) {
1933	>	if (binCount >= TREEIFY_THRESHOLD)
1934	>	treeifyBin(tab, i);
1935	>	break;
1936	>	}
1937	>	}
1938	>	}
1939	>	if (delta != 0)
1940	>	addCount((long)delta, binCount);
1941	>	return val;
1942	>	}
1943	>
1944	>	/**
1945	>	* If the specified key is not already associated with a
1946	>	* (non-null) value, associates it with the given value.
1947	>	* Otherwise, replaces the value with the results of the given
1948	>	* remapping function, or removes if {@code null}. The entire
1949	>	* method invocation is performed atomically.  Some attempted
1950	>	* update operations on this map by other threads may be blocked
1951	>	* while computation is in progress, so the computation should be
1952	>	* short and simple, and must not attempt to update any other
1953	>	* mappings of this Map.
1954	>	*
1955	>	* @param key key with which the specified value is to be associated
1956	>	* @param value the value to use if absent
1957	>	* @param remappingFunction the function to recompute a value if present
1958	>	* @return the new value associated with the specified key, or null if none
1959	>	* @throws NullPointerException if the specified key or the
1960	>	*         remappingFunction is null
1961	>	* @throws RuntimeException or Error if the remappingFunction does so,
1962	>	*         in which case the mapping is unchanged
1963	>	*/
1964	>	public V merge(K key, V value, BiFun<? super V, ? super V, ? extends V> remappingFunction) {
1965	>	if (key == null || value == null || remappingFunction == null)
1966	>	throw new NullPointerException();
1967	>	int h = spread(key.hashCode());
1968	>	V val = null;
1969	>	int delta = 0;
1970	>	int binCount = 0;
1971	>	for (Node<K,V>[] tab = table;;) {
1972	>	Node<K,V> f; int n, i, fh;
1973	>	if (tab == null || (n = tab.length) == 0)
1974	>	tab = initTable();
1975	>	else if ((f = tabAt(tab, i = (n - 1) & h)) == null) {
1976	>	if (casTabAt(tab, i, null, new Node<K,V>(h, key, value, null))) {
1977	>	delta = 1;
1978	>	val = value;
1979	>	break;
1980	>	}
1981	>	}
1982	>	else if ((fh = f.hash) == MOVED)
1983	>	tab = helpTransfer(tab, f);
1984	>	else {
1985	>	synchronized (f) {
1986	>	if (tabAt(tab, i) == f) {
1987	>	if (fh >= 0) {
1988	>	binCount = 1;
1989	>	for (Node<K,V> e = f, pred = null;; ++binCount) {
1990	>	K ek;
1991	>	if (e.hash == h &&
1992	>	((ek = e.key) == key ||
1993	>	(ek != null && key.equals(ek)))) {
1994	>	val = remappingFunction.apply(e.val, value);
1995	>	if (val != null)
1996	>	e.val = val;
1997	>	else {
1998	>	delta = -1;
1999	>	Node<K,V> en = e.next;
2000	>	if (pred != null)
2001	>	pred.next = en;
2002	>	else
2003	>	setTabAt(tab, i, en);
2004	>	}
2005	>	break;
2006	>	}
2007	>	pred = e;
2008	>	if ((e = e.next) == null) {
2009	>	delta = 1;
2010	>	val = value;
2011	>	pred.next =
2012	>	new Node<K,V>(h, key, val, null);
2013	>	break;
2014	>	}
2015	>	}
2016	>	}
2017	>	else if (f instanceof TreeBin) {
2018	>	binCount = 2;
2019	>	TreeBin<K,V> t = (TreeBin<K,V>)f;
2020	>	TreeNode<K,V> r = t.root;
2021	>	TreeNode<K,V> p = (r == null) ? null :
2022	>	r.findTreeNode(h, key, null);
2023	>	val = (p == null) ? value :
2024	>	remappingFunction.apply(p.val, value);
2025	>	if (val != null) {
2026	>	if (p != null)
2027	>	p.val = val;
2028	>	else {
2029	>	delta = 1;
2030	>	t.putTreeVal(h, key, val);
2031	>	}
2032	>	}
2033	>	else if (p != null) {
2034	>	delta = -1;
2035	>	if (t.removeTreeNode(p))
2036	>	setTabAt(tab, i, untreeify(t.first));
2037	>	}
2038	>	}
2039	>	}
2040	>	}
2041	>	if (binCount != 0) {
2042	>	if (binCount >= TREEIFY_THRESHOLD)
2043	>	treeifyBin(tab, i);
2044	>	break;
2045	>	}
2046	>	}
2047	>	}
2048	>	if (delta != 0)
2049	>	addCount((long)delta, binCount);
2050	>	return val;
2051	>	}
2052	>
2053	>	// Hashtable legacy methods
2054	>
2055	>	/**
2056	>	* Legacy method testing if some key maps into the specified value
2057	>	* in this table.  This method is identical in functionality to
2058	>	* {@link #containsValue(Object)}, and exists solely to ensure
2059	>	* full compatibility with class {@link java.util.Hashtable},
2060	>	* which supported this method prior to introduction of the
2061	>	* Java Collections framework.
2062	>	*
2063	>	* @param  value a value to search for
2064	>	* @return {@code true} if and only if some key maps to the
2065	>	*         {@code value} argument in this table as
2066	>	*         determined by the {@code equals} method;
2067	>	*         {@code false} otherwise
2068	>	* @throws NullPointerException if the specified value is null
2069	>	*/
2070	>	@Deprecated public boolean contains(Object value) {
2071	>	return containsValue(value);
2072	>	}
2073	>
2074	>	/**
2075	>	* Returns an enumeration of the keys in this table.
2076	>	*
2077	>	* @return an enumeration of the keys in this table
2078	>	* @see #keySet()
2079	>	*/
2080	>	public Enumeration<K> keys() {
2081	>	Node<K,V>[] t;
2082	>	int f = (t = table) == null ? 0 : t.length;
2083	>	return new KeyIterator<K,V>(t, f, 0, f, this);
2084	>	}
2085	>
2086	>	/**
2087	>	* Returns an enumeration of the values in this table.
2088	>	*
2089	>	* @return an enumeration of the values in this table
2090	>	* @see #values()
2091	>	*/
2092	>	public Enumeration<V> elements() {
2093	>	Node<K,V>[] t;
2094	>	int f = (t = table) == null ? 0 : t.length;
2095	>	return new ValueIterator<K,V>(t, f, 0, f, this);
2096	>	}
2097	>
2098	>	// ConcurrentHashMapV8-only methods
2099	>
2100	>	/**
2101	>	* Returns the number of mappings. This method should be used
2102	>	* instead of {@link #size} because a ConcurrentHashMapV8 may
2103	>	* contain more mappings than can be represented as an int. The
2104	>	* value returned is an estimate; the actual count may differ if
2105	>	* there are concurrent insertions or removals.
2106	>	*
2107	>	* @return the number of mappings
2108	>	* @since 1.8
2109	>	*/
2110	>	public long mappingCount() {
2111	>	long n = sumCount();
2112	>	return (n < 0L) ? 0L : n; // ignore transient negative values
2113	>	}
2114	>
2115	>	/**
2116	>	* Creates a new {@link Set} backed by a ConcurrentHashMapV8
2117	>	* from the given type to {@code Boolean.TRUE}.
2118	>	*
2119	>	* @return the new set
2120	>	* @since 1.8
2121	>	*/
2122	>	public static <K> KeySetView<K,Boolean> newKeySet() {
2123	>	return new KeySetView<K,Boolean>
2124	>	(new ConcurrentHashMapV8<K,Boolean>(), Boolean.TRUE);
2125	>	}
2126	>
2127	>	/**
2128	>	* Creates a new {@link Set} backed by a ConcurrentHashMapV8
2129	>	* from the given type to {@code Boolean.TRUE}.
2130	>	*
2131	>	* @param initialCapacity The implementation performs internal
2132	>	* sizing to accommodate this many elements.
2133	>	* @return the new set
2134	>	* @throws IllegalArgumentException if the initial capacity of
2135	>	* elements is negative
2136	>	* @since 1.8
2137	>	*/
2138	>	public static <K> KeySetView<K,Boolean> newKeySet(int initialCapacity) {
2139	>	return new KeySetView<K,Boolean>
2140	>	(new ConcurrentHashMapV8<K,Boolean>(initialCapacity), Boolean.TRUE);
2141	>	}
2142	>
2143	>	/**
2144	>	* Returns a {@link Set} view of the keys in this map, using the
2145	>	* given common mapped value for any additions (i.e., {@link
2146	>	* Collection#add} and {@link Collection#addAll(Collection)}).
2147	>	* This is of course only appropriate if it is acceptable to use
2148	>	* the same value for all additions from this view.
2149	>	*
2150	>	* @param mappedValue the mapped value to use for any additions
2151	>	* @return the set view
2152	>	* @throws NullPointerException if the mappedValue is null
2153	>	*/
2154	>	public KeySetView<K,V> keySet(V mappedValue) {
2155	>	if (mappedValue == null)
2156	>	throw new NullPointerException();
2157	>	return new KeySetView<K,V>(this, mappedValue);
2158	>	}
2159	>
2160	>	/* ---------------- Special Nodes -------------- */
2161	>
2162	>	/**
2163	>	* A node inserted at head of bins during transfer operations.
2164	>	*/
2165	>	static final class ForwardingNode<K,V> extends Node<K,V> {
2166	>	final Node<K,V>[] nextTable;
2167	>	ForwardingNode(Node<K,V>[] tab) {
2168	>	super(MOVED, null, null, null);
2169	>	this.nextTable = tab;
2170	>	}
2171	>
2172	>	Node<K,V> find(int h, Object k) {
2173	>	// loop to avoid arbitrarily deep recursion on forwarding nodes
2174	>	outer: for (Node<K,V>[] tab = nextTable;;) {
2175	>	Node<K,V> e; int n;
2176	>	if (k == null || tab == null || (n = tab.length) == 0 ||
2177	>	(e = tabAt(tab, (n - 1) & h)) == null)
2178	>	return null;
2179	>	for (;;) {
2180	>	int eh; K ek;
2181	>	if ((eh = e.hash) == h &&
2182	>	((ek = e.key) == k || (ek != null && k.equals(ek))))
2183	>	return e;
2184	>	if (eh < 0) {
2185	>	if (e instanceof ForwardingNode) {
2186	>	tab = ((ForwardingNode<K,V>)e).nextTable;
2187	>	continue outer;
2188	>	}
2189	>	else
2190	>	return e.find(h, k);
2191	>	}
2192	>	if ((e = e.next) == null)
2193	>	return null;
2194	>	}
2195	>	}
2196	>	}
2197	>	}
2198	>
2199	>	/**
2200	>	* A place-holder node used in computeIfAbsent and compute
2201	>	*/
2202	>	static final class ReservationNode<K,V> extends Node<K,V> {
2203	>	ReservationNode() {
2204	>	super(RESERVED, null, null, null);
2205	>	}
2206	>
2207	>	Node<K,V> find(int h, Object k) {
2208	>	return null;
2209	>	}
2210	>	}
2211	>
2212	>	/* ---------------- Table Initialization and Resizing -------------- */
2213	>
2214	>	/**
2215	>	* Returns the stamp bits for resizing a table of size n.
2216	>	* Must be negative when shifted left by RESIZE_STAMP_SHIFT.
2217	>	*/
2218	>	static final int resizeStamp(int n) {
2219	>	return Integer.numberOfLeadingZeros(n) | (1 << (RESIZE_STAMP_BITS - 1));
2220	>	}
2221	>
2222	>	/**
2223	>	* Initializes table, using the size recorded in sizeCtl.
2224	>	*/
2225	>	private final Node<K,V>[] initTable() {
2226	>	Node<K,V>[] tab; int sc;
2227	>	while ((tab = table) == null || tab.length == 0) {
2228	>	if ((sc = sizeCtl) < 0)
2229	>	Thread.yield(); // lost initialization race; just spin
2230	>	else if (U.compareAndSwapInt(this, SIZECTL, sc, -1)) {
2231	>	try {
2232	>	if ((tab = table) == null || tab.length == 0) {
2233	>	int n = (sc > 0) ? sc : DEFAULT_CAPACITY;
2234	>	@SuppressWarnings("unchecked")
2235	>	Node<K,V>[] nt = (Node<K,V>[])new Node<?,?>[n];
2236	>	table = tab = nt;
2237	>	sc = n - (n >>> 2);
2238	>	}
2239	>	} finally {
2240	>	sizeCtl = sc;
2241	>	}
2242	>	break;
2243	>	}
2244	>	}
2245	>	return tab;
2246	>	}
2247	>
2248	>	/**
2249	>	* Adds to count, and if table is too small and not already
2250	>	* resizing, initiates transfer. If already resizing, helps
2251	>	* perform transfer if work is available.  Rechecks occupancy
2252	>	* after a transfer to see if another resize is already needed
2253	>	* because resizings are lagging additions.
2254	>	*
2255	>	* @param x the count to add
2256	>	* @param check if <0, don't check resize, if <= 1 only check if uncontended
2257	>	*/
2258	>	private final void addCount(long x, int check) {
2259	>	CounterCell[] as; long b, s;
2260	>	if ((as = counterCells) != null ||
2261	>	!U.compareAndSwapLong(this, BASECOUNT, b = baseCount, s = b + x)) {
2262	>	CounterHashCode hc; CounterCell a; long v; int m;
2263	>	boolean uncontended = true;
2264	>	if ((hc = threadCounterHashCode.get()) == null ||
2265	>	as == null || (m = as.length - 1) < 0 ||
2266	>	(a = as[m & hc.code]) == null ||
2267	>	!(uncontended =
2268	>	U.compareAndSwapLong(a, CELLVALUE, v = a.value, v + x))) {
2269	>	fullAddCount(x, hc, uncontended);
2270	>	return;
2271	>	}
2272	>	if (check <= 1)
2273	>	return;
2274	>	s = sumCount();
2275	>	}
2276	>	if (check >= 0) {
2277	>	Node<K,V>[] tab, nt; int n, sc;
2278	>	while (s >= (long)(sc = sizeCtl) && (tab = table) != null &&
2279	>	(n = tab.length) < MAXIMUM_CAPACITY) {
2280	>	int rs = resizeStamp(n);
2281	>	if (sc < 0) {
2282	>	if ((sc >>> RESIZE_STAMP_SHIFT) != rs || sc == rs + 1 ||
2283	>	sc == rs + MAX_RESIZERS || (nt = nextTable) == null ||
2284	>	transferIndex <= 0)
2285	>	break;
2286	>	if (U.compareAndSwapInt(this, SIZECTL, sc, sc + 1))
2287	>	transfer(tab, nt);
2288	>	}
2289	>	else if (U.compareAndSwapInt(this, SIZECTL, sc,
2290	>	(rs << RESIZE_STAMP_SHIFT) + 2))
2291	>	transfer(tab, null);
2292	>	s = sumCount();
2293	>	}
2294	>	}
2295	>	}
2296	>
2297	>	/**
2298	>	* Helps transfer if a resize is in progress.
2299	>	*/
2300	>	final Node<K,V>[] helpTransfer(Node<K,V>[] tab, Node<K,V> f) {
2301	>	Node<K,V>[] nextTab; int sc;
2302	>	if (tab != null && (f instanceof ForwardingNode) &&
2303	>	(nextTab = ((ForwardingNode<K,V>)f).nextTable) != null) {
2304	>	int rs = resizeStamp(tab.length);
2305	>	while (nextTab == nextTable && table == tab &&
2306	>	(sc = sizeCtl) < 0) {
2307	>	if ((sc >>> RESIZE_STAMP_SHIFT) != rs || sc == rs + 1 ||
2308	>	sc == rs + MAX_RESIZERS || transferIndex <= 0)
2309	>	break;
2310	>	if (U.compareAndSwapInt(this, SIZECTL, sc, sc + 1)) {
2311	>	transfer(tab, nextTab);
2312	>	break;
2313	>	}
2314	>	}
2315	>	return nextTab;
2316	>	}
2317	>	return table;
2318	>	}
2319	>
2320	>	/**
2321	>	* Tries to presize table to accommodate the given number of elements.
2322	>	*
2323	>	* @param size number of elements (doesn't need to be perfectly accurate)
2324	>	*/
2325	>	private final void tryPresize(int size) {
2326	>	int c = (size >= (MAXIMUM_CAPACITY >>> 1)) ? MAXIMUM_CAPACITY :
2327	>	tableSizeFor(size + (size >>> 1) + 1);
2328	>	int sc;
2329	>	while ((sc = sizeCtl) >= 0) {
2330	>	Node<K,V>[] tab = table; int n;
2331	>	if (tab == null || (n = tab.length) == 0) {
2332	>	n = (sc > c) ? sc : c;
2333	>	if (U.compareAndSwapInt(this, SIZECTL, sc, -1)) {
2334	>	try {
2335	>	if (table == tab) {
2336	>	@SuppressWarnings("unchecked")
2337	>	Node<K,V>[] nt = (Node<K,V>[])new Node<?,?>[n];
2338	>	table = nt;
2339	>	sc = n - (n >>> 2);
2340	>	}
2341	>	} finally {
2342	>	sizeCtl = sc;
2343	>	}
2344	>	}
2345	>	}
2346	>	else if (c <= sc || n >= MAXIMUM_CAPACITY)
2347	>	break;
2348	>	else if (tab == table) {
2349	>	int rs = resizeStamp(n);
2350	>	if (sc < 0) {
2351	>	Node<K,V>[] nt;
2352	>	if ((sc >>> RESIZE_STAMP_SHIFT) != rs || sc == rs + 1 ||
2353	>	sc == rs + MAX_RESIZERS || (nt = nextTable) == null ||
2354	>	transferIndex <= 0)
2355	>	break;
2356	>	if (U.compareAndSwapInt(this, SIZECTL, sc, sc + 1))
2357	>	transfer(tab, nt);
2358	>	}
2359	>	else if (U.compareAndSwapInt(this, SIZECTL, sc,
2360	>	(rs << RESIZE_STAMP_SHIFT) + 2))
2361	>	transfer(tab, null);
2362	>	}
2363	>	}
2364	>	}
2365	>
2366	>	/**
2367	>	* Moves and/or copies the nodes in each bin to new table. See
2368	>	* above for explanation.
2369	>	*/
2370	>	private final void transfer(Node<K,V>[] tab, Node<K,V>[] nextTab) {
2371	>	int n = tab.length, stride;
2372	>	if ((stride = (NCPU > 1) ? (n >>> 3) / NCPU : n) < MIN_TRANSFER_STRIDE)
2373	>	stride = MIN_TRANSFER_STRIDE; // subdivide range
2374	>	if (nextTab == null) {            // initiating
2375	>	try {
2376	>	@SuppressWarnings("unchecked")
2377	>	Node<K,V>[] nt = (Node<K,V>[])new Node<?,?>[n << 1];
2378	>	nextTab = nt;
2379	>	} catch (Throwable ex) {      // try to cope with OOME
2380	>	sizeCtl = Integer.MAX_VALUE;
2381	>	return;
2382	>	}
2383	>	nextTable = nextTab;
2384	>	transferIndex = n;
2385	>	}
2386	>	int nextn = nextTab.length;
2387	>	ForwardingNode<K,V> fwd = new ForwardingNode<K,V>(nextTab);
2388	>	boolean advance = true;
2389	>	boolean finishing = false; // to ensure sweep before committing nextTab
2390	>	for (int i = 0, bound = 0;;) {
2391	>	Node<K,V> f; int fh;
2392	>	while (advance) {
2393	>	int nextIndex, nextBound;
2394	>	if (--i >= bound || finishing)
2395	>	advance = false;
2396	>	else if ((nextIndex = transferIndex) <= 0) {
2397	>	i = -1;
2398	>	advance = false;
2399	>	}
2400	>	else if (U.compareAndSwapInt
2401	>	(this, TRANSFERINDEX, nextIndex,
2402	>	nextBound = (nextIndex > stride ?
2403	>	nextIndex - stride : 0))) {
2404	>	bound = nextBound;
2405	>	i = nextIndex - 1;
2406	>	advance = false;
2407	>	}
2408	>	}
2409	>	if (i < 0 || i >= n || i + n >= nextn) {
2410	>	int sc;
2411	>	if (finishing) {
2412	>	nextTable = null;
2413	>	table = nextTab;
2414	>	sizeCtl = (n << 1) - (n >>> 1);
2415	>	return;
2416	>	}
2417	>	if (U.compareAndSwapInt(this, SIZECTL, sc = sizeCtl, sc - 1)) {
2418	>	if ((sc - 2) != resizeStamp(n) << RESIZE_STAMP_SHIFT)
2419	>	return;
2420	>	finishing = advance = true;
2421	>	i = n; // recheck before commit
2422	>	}
2423	>	}
2424	>	else if ((f = tabAt(tab, i)) == null)
2425	>	advance = casTabAt(tab, i, null, fwd);
2426	>	else if ((fh = f.hash) == MOVED)
2427	>	advance = true; // already processed
2428	>	else {
2429	>	synchronized (f) {
2430	>	if (tabAt(tab, i) == f) {
2431	>	Node<K,V> ln, hn;
2432	>	if (fh >= 0) {
2433	>	int runBit = fh & n;
2434	>	Node<K,V> lastRun = f;
2435	>	for (Node<K,V> p = f.next; p != null; p = p.next) {
2436	>	int b = p.hash & n;
2437	>	if (b != runBit) {
2438	>	runBit = b;
2439	>	lastRun = p;
2440	>	}
2441	>	}
2442	>	if (runBit == 0) {
2443	>	ln = lastRun;
2444	>	hn = null;
2445	>	}
2446	>	else {
2447	>	hn = lastRun;
2448	>	ln = null;
2449	>	}
2450	>	for (Node<K,V> p = f; p != lastRun; p = p.next) {
2451	>	int ph = p.hash; K pk = p.key; V pv = p.val;
2452	>	if ((ph & n) == 0)
2453	>	ln = new Node<K,V>(ph, pk, pv, ln);
2454	>	else
2455	>	hn = new Node<K,V>(ph, pk, pv, hn);
2456	>	}
2457	>	setTabAt(nextTab, i, ln);
2458	>	setTabAt(nextTab, i + n, hn);
2459	>	setTabAt(tab, i, fwd);
2460	>	advance = true;
2461	>	}
2462	>	else if (f instanceof TreeBin) {
2463	>	TreeBin<K,V> t = (TreeBin<K,V>)f;
2464	>	TreeNode<K,V> lo = null, loTail = null;
2465	>	TreeNode<K,V> hi = null, hiTail = null;
2466	>	int lc = 0, hc = 0;
2467	>	for (Node<K,V> e = t.first; e != null; e = e.next) {
2468	>	int h = e.hash;
2469	>	TreeNode<K,V> p = new TreeNode<K,V>
2470	>	(h, e.key, e.val, null, null);
2471	>	if ((h & n) == 0) {
2472	>	if ((p.prev = loTail) == null)
2473	>	lo = p;
2474	>	else
2475	>	loTail.next = p;
2476	>	loTail = p;
2477	>	++lc;
2478	>	}
2479	>	else {
2480	>	if ((p.prev = hiTail) == null)
2481	>	hi = p;
2482	>	else
2483	>	hiTail.next = p;
2484	>	hiTail = p;
2485	>	++hc;
2486	>	}
2487	>	}
2488	>	ln = (lc <= UNTREEIFY_THRESHOLD) ? untreeify(lo) :
2489	>	(hc != 0) ? new TreeBin<K,V>(lo) : t;
2490	>	hn = (hc <= UNTREEIFY_THRESHOLD) ? untreeify(hi) :
2491	>	(lc != 0) ? new TreeBin<K,V>(hi) : t;
2492	>	setTabAt(nextTab, i, ln);
2493	>	setTabAt(nextTab, i + n, hn);
2494	>	setTabAt(tab, i, fwd);
2495	>	advance = true;
2496	>	}
2497	>	}
2498	>	}
2499	>	}
2500	>	}
2501	>	}
2502	>
2503	>	/* ---------------- Conversion from/to TreeBins -------------- */
2504	>
2505	>	/**
2506	>	* Replaces all linked nodes in bin at given index unless table is
2507	>	* too small, in which case resizes instead.
2508	>	*/
2509	>	private final void treeifyBin(Node<K,V>[] tab, int index) {
2510	>	Node<K,V> b; int n, sc;
2511	>	if (tab != null) {
2512	>	if ((n = tab.length) < MIN_TREEIFY_CAPACITY)
2513	>	tryPresize(n << 1);
2514	>	else if ((b = tabAt(tab, index)) != null && b.hash >= 0) {
2515	>	synchronized (b) {
2516	>	if (tabAt(tab, index) == b) {
2517	>	TreeNode<K,V> hd = null, tl = null;
2518	>	for (Node<K,V> e = b; e != null; e = e.next) {
2519	>	TreeNode<K,V> p =
2520	>	new TreeNode<K,V>(e.hash, e.key, e.val,
2521	>	null, null);
2522	>	if ((p.prev = tl) == null)
2523	>	hd = p;
2524	>	else
2525	>	tl.next = p;
2526	>	tl = p;
2527	>	}
2528	>	setTabAt(tab, index, new TreeBin<K,V>(hd));
2529	>	}
2530	>	}
2531	>	}
2532	>	}
2533	>	}
2534	>
2535	>	/**
2536	>	* Returns a list of non-TreeNodes replacing those in given list.
2537	>	*/
2538	>	static <K,V> Node<K,V> untreeify(Node<K,V> b) {
2539	>	Node<K,V> hd = null, tl = null;
2540	>	for (Node<K,V> q = b; q != null; q = q.next) {
2541	>	Node<K,V> p = new Node<K,V>(q.hash, q.key, q.val, null);
2542	>	if (tl == null)
2543	>	hd = p;
2544	>	else
2545	>	tl.next = p;
2546	>	tl = p;
2547	>	}
2548	>	return hd;
2549	>	}
2550	>
2551	>	/* ---------------- TreeNodes -------------- */
2552	>
2553	>	/**
2554	>	* Nodes for use in TreeBins
2555	>	*/
2556	>	static final class TreeNode<K,V> extends Node<K,V> {
2557	>	TreeNode<K,V> parent;  // red-black tree links
2558	>	TreeNode<K,V> left;
2559	>	TreeNode<K,V> right;
2560	>	TreeNode<K,V> prev;    // needed to unlink next upon deletion
2561	>	boolean red;
2562	>
2563	>	TreeNode(int hash, K key, V val, Node<K,V> next,
2564	>	TreeNode<K,V> parent) {
2565	>	super(hash, key, val, next);
2566	>	this.parent = parent;
2567	>	}
2568	>
2569	>	Node<K,V> find(int h, Object k) {
2570	>	return findTreeNode(h, k, null);
2571	>	}
2572	>
2573	>	/**
2574	>	* Returns the TreeNode (or null if not found) for the given key
2575	>	* starting at given root.
2576	>	*/
2577	>	final TreeNode<K,V> findTreeNode(int h, Object k, Class<?> kc) {
2578	>	if (k != null) {
2579	>	TreeNode<K,V> p = this;
2580	>	do {
2581	>	int ph, dir; K pk; TreeNode<K,V> q;
2582	>	TreeNode<K,V> pl = p.left, pr = p.right;
2583	>	if ((ph = p.hash) > h)
2584	>	p = pl;
2585	>	else if (ph < h)
2586	>	p = pr;
2587	>	else if ((pk = p.key) == k || (pk != null && k.equals(pk)))
2588	>	return p;
2589	>	else if (pl == null)
2590	>	p = pr;
2591	>	else if (pr == null)
2592	>	p = pl;
2593	>	else if ((kc != null ||
2594	>	(kc = comparableClassFor(k)) != null) &&
2595	>	(dir = compareComparables(kc, k, pk)) != 0)
2596	>	p = (dir < 0) ? pl : pr;
2597	>	else if ((q = pr.findTreeNode(h, k, kc)) != null)
2598	>	return q;
2599	>	else
2600	>	p = pl;
2601	>	} while (p != null);
2602	>	}
2603	>	return null;
2604	>	}
2605	>	}
2606	>
2607	>	/* ---------------- TreeBins -------------- */
2608	>
2609	>	/**
2610	>	* TreeNodes used at the heads of bins. TreeBins do not hold user
2611	>	* keys or values, but instead point to list of TreeNodes and
2612	>	* their root. They also maintain a parasitic read-write lock
2613	>	* forcing writers (who hold bin lock) to wait for readers (who do
2614	>	* not) to complete before tree restructuring operations.
2615	>	*/
2616	>	static final class TreeBin<K,V> extends Node<K,V> {
2617	>	TreeNode<K,V> root;
2618	>	volatile TreeNode<K,V> first;
2619	>	volatile Thread waiter;
2620	>	volatile int lockState;
2621	>	// values for lockState
2622	>	static final int WRITER = 1; // set while holding write lock
2623	>	static final int WAITER = 2; // set when waiting for write lock
2624	>	static final int READER = 4; // increment value for setting read lock
2625	>
2626	>	/**
2627	>	* Tie-breaking utility for ordering insertions when equal
2628	>	* hashCodes and non-comparable. We don't require a total
2629	>	* order, just a consistent insertion rule to maintain
2630	>	* equivalence across rebalancings. Tie-breaking further than
2631	>	* necessary simplifies testing a bit.
2632	>	*/
2633	>	static int tieBreakOrder(Object a, Object b) {
2634	>	int d;
2635	>	if (a == null || b == null ||
2636	>	(d = a.getClass().getName().
2637	>	compareTo(b.getClass().getName())) == 0)
2638	>	d = (System.identityHashCode(a) <= System.identityHashCode(b) ?
2639	>	-1 : 1);
2640	>	return d;
2641	>	}
2642	>
2643	>	/**
2644	>	* Creates bin with initial set of nodes headed by b.
2645	>	*/
2646	>	TreeBin(TreeNode<K,V> b) {
2647	>	super(TREEBIN, null, null, null);
2648	>	this.first = b;
2649	>	TreeNode<K,V> r = null;
2650	>	for (TreeNode<K,V> x = b, next; x != null; x = next) {
2651	>	next = (TreeNode<K,V>)x.next;
2652	>	x.left = x.right = null;
2653	>	if (r == null) {
2654	>	x.parent = null;
2655	>	x.red = false;
2656	>	r = x;
2657	>	}
2658	>	else {
2659	>	K k = x.key;
2660	>	int h = x.hash;
2661	>	Class<?> kc = null;
2662	>	for (TreeNode<K,V> p = r;;) {
2663	>	int dir, ph;
2664	>	K pk = p.key;
2665	>	if ((ph = p.hash) > h)
2666	>	dir = -1;
2667	>	else if (ph < h)
2668	>	dir = 1;
2669	>	else if ((kc == null &&
2670	>	(kc = comparableClassFor(k)) == null) ||
2671	>	(dir = compareComparables(kc, k, pk)) == 0)
2672	>	dir = tieBreakOrder(k, pk);
2673	>	TreeNode<K,V> xp = p;
2674	>	if ((p = (dir <= 0) ? p.left : p.right) == null) {
2675	>	x.parent = xp;
2676	>	if (dir <= 0)
2677	>	xp.left = x;
2678	>	else
2679	>	xp.right = x;
2680	>	r = balanceInsertion(r, x);
2681	>	break;
2682	>	}
2683	>	}
2684	>	}
2685	>	}
2686	>	this.root = r;
2687	>	assert checkInvariants(root);
2688	>	}
2689	>
2690	>	/**
2691	>	* Acquires write lock for tree restructuring.
2692	>	*/
2693	>	private final void lockRoot() {
2694	>	if (!U.compareAndSwapInt(this, LOCKSTATE, 0, WRITER))
2695	>	contendedLock(); // offload to separate method
2696	>	}
2697	>
2698	>	/**
2699	>	* Releases write lock for tree restructuring.
2700	>	*/
2701	>	private final void unlockRoot() {
2702	>	lockState = 0;
2703	>	}
2704	>
2705	>	/**
2706	>	* Possibly blocks awaiting root lock.
2707	>	*/
2708	>	private final void contendedLock() {
2709	>	boolean waiting = false;
2710	>	for (int s;;) {
2711	>	if (((s = lockState) & ~WAITER) == 0) {
2712	>	if (U.compareAndSwapInt(this, LOCKSTATE, s, WRITER)) {
2713	>	if (waiting)
2714	>	waiter = null;
2715	>	return;
2716	>	}
2717	>	}
2718	>	else if ((s & WAITER) == 0) {
2719	>	if (U.compareAndSwapInt(this, LOCKSTATE, s, s | WAITER)) {
2720	>	waiting = true;
2721	>	waiter = Thread.currentThread();
2722	>	}
2723	>	}
2724	>	else if (waiting)
2725	>	LockSupport.park(this);
2726	>	}
2727	>	}
2728	>
2729	>	/**
2730	>	* Returns matching node or null if none. Tries to search
2731	>	* using tree comparisons from root, but continues linear
2732	>	* search when lock not available.
2733	>	*/
2734	>	final Node<K,V> find(int h, Object k) {
2735	>	if (k != null) {
2736	>	for (Node<K,V> e = first; e != null; ) {
2737	>	int s; K ek;
2738	>	if (((s = lockState) & (WAITER|WRITER)) != 0) {
2739	>	if (e.hash == h &&
2740	>	((ek = e.key) == k || (ek != null && k.equals(ek))))
2741	>	return e;
2742	>	e = e.next;
2743	>	}
2744	>	else if (U.compareAndSwapInt(this, LOCKSTATE, s,
2745	>	s + READER)) {
2746	>	TreeNode<K,V> r, p;
2747	>	try {
2748	>	p = ((r = root) == null ? null :
2749	>	r.findTreeNode(h, k, null));
2750	>	} finally {
2751	>	Thread w;
2752	>	int ls;
2753	>	do {} while (!U.compareAndSwapInt
2754	>	(this, LOCKSTATE,
2755	>	ls = lockState, ls - READER));
2756	>	if (ls == (READER|WAITER) && (w = waiter) != null)
2757	>	LockSupport.unpark(w);
2758	>	}
2759	>	return p;
2760	>	}
2761	>	}
2762	>	}
2763	>	return null;
2764	>	}
2765	>
2766	>	/**
2767	>	* Finds or adds a node.
2768	>	* @return null if added
2769	>	*/
2770	>	final TreeNode<K,V> putTreeVal(int h, K k, V v) {
2771	>	Class<?> kc = null;
2772	>	boolean searched = false;
2773	>	for (TreeNode<K,V> p = root;;) {
2774	>	int dir, ph; K pk;
2775	>	if (p == null) {
2776	>	first = root = new TreeNode<K,V>(h, k, v, null, null);
2777	>	break;
2778	>	}
2779	>	else if ((ph = p.hash) > h)
2780	>	dir = -1;
2781	>	else if (ph < h)
2782	>	dir = 1;
2783	>	else if ((pk = p.key) == k || (pk != null && k.equals(pk)))
2784	>	return p;
2785	>	else if ((kc == null &&
2786	>	(kc = comparableClassFor(k)) == null) ||
2787	>	(dir = compareComparables(kc, k, pk)) == 0) {
2788	>	if (!searched) {
2789	>	TreeNode<K,V> q, ch;
2790	>	searched = true;
2791	>	if (((ch = p.left) != null &&
2792	>	(q = ch.findTreeNode(h, k, kc)) != null) ||
2793	>	((ch = p.right) != null &&
2794	>	(q = ch.findTreeNode(h, k, kc)) != null))
2795	>	return q;
2796	>	}
2797	>	dir = tieBreakOrder(k, pk);
2798	>	}
2799	>
2800	>	TreeNode<K,V> xp = p;
2801	>	if ((p = (dir <= 0) ? p.left : p.right) == null) {
2802	>	TreeNode<K,V> x, f = first;
2803	>	first = x = new TreeNode<K,V>(h, k, v, f, xp);
2804	>	if (f != null)
2805	>	f.prev = x;
2806	>	if (dir <= 0)
2807	>	xp.left = x;
2808	>	else
2809	>	xp.right = x;
2810	>	if (!xp.red)
2811	>	x.red = true;
2812	>	else {
2813	>	lockRoot();
2814	>	try {
2815	>	root = balanceInsertion(root, x);
2816	>	} finally {
2817	>	unlockRoot();
2818	>	}
2819	>	}
2820	>	break;
2821	>	}
2822	>	}
2823	>	assert checkInvariants(root);
2824	>	return null;
2825	>	}
2826	>
2827	>	/**
2828	>	* Removes the given node, that must be present before this
2829	>	* call.  This is messier than typical red-black deletion code
2830	>	* because we cannot swap the contents of an interior node
2831	>	* with a leaf successor that is pinned by "next" pointers
2832	>	* that are accessible independently of lock. So instead we
2833	>	* swap the tree linkages.
2834	>	*
2835	>	* @return true if now too small, so should be untreeified
2836	>	*/
2837	>	final boolean removeTreeNode(TreeNode<K,V> p) {
2838	>	TreeNode<K,V> next = (TreeNode<K,V>)p.next;
2839	>	TreeNode<K,V> pred = p.prev;  // unlink traversal pointers
2840	>	TreeNode<K,V> r, rl;
2841	>	if (pred == null)
2842	>	first = next;
2843	>	else
2844	>	pred.next = next;
2845	>	if (next != null)
2846	>	next.prev = pred;
2847	>	if (first == null) {
2848	>	root = null;
2849	>	return true;
2850	>	}
2851	>	if ((r = root) == null || r.right == null || // too small
2852	>	(rl = r.left) == null || rl.left == null)
2853	>	return true;
2854	>	lockRoot();
2855	>	try {
2856	>	TreeNode<K,V> replacement;
2857	>	TreeNode<K,V> pl = p.left;
2858	>	TreeNode<K,V> pr = p.right;
2859	>	if (pl != null && pr != null) {
2860	>	TreeNode<K,V> s = pr, sl;
2861	>	while ((sl = s.left) != null) // find successor
2862	>	s = sl;
2863	>	boolean c = s.red; s.red = p.red; p.red = c; // swap colors
2864	>	TreeNode<K,V> sr = s.right;
2865	>	TreeNode<K,V> pp = p.parent;
2866	>	if (s == pr) { // p was s's direct parent
2867	>	p.parent = s;
2868	>	s.right = p;
2869	>	}
2870	>	else {
2871	>	TreeNode<K,V> sp = s.parent;
2872	>	if ((p.parent = sp) != null) {
2873	>	if (s == sp.left)
2874	>	sp.left = p;
2875	>	else
2876	>	sp.right = p;
2877	>	}
2878	>	if ((s.right = pr) != null)
2879	>	pr.parent = s;
2880	>	}
2881	>	p.left = null;
2882	>	if ((p.right = sr) != null)
2883	>	sr.parent = p;
2884	>	if ((s.left = pl) != null)
2885	>	pl.parent = s;
2886	>	if ((s.parent = pp) == null)
2887	>	r = s;
2888	>	else if (p == pp.left)
2889	>	pp.left = s;
2890	>	else
2891	>	pp.right = s;
2892	>	if (sr != null)
2893	>	replacement = sr;
2894	>	else
2895	>	replacement = p;
2896	>	}
2897	>	else if (pl != null)
2898	>	replacement = pl;
2899	>	else if (pr != null)
2900	>	replacement = pr;
2901	>	else
2902	>	replacement = p;
2903	>	if (replacement != p) {
2904	>	TreeNode<K,V> pp = replacement.parent = p.parent;
2905	>	if (pp == null)
2906	>	r = replacement;
2907	>	else if (p == pp.left)
2908	>	pp.left = replacement;
2909	>	else
2910	>	pp.right = replacement;
2911	>	p.left = p.right = p.parent = null;
2912	>	}
2913	>
2914	>	root = (p.red) ? r : balanceDeletion(r, replacement);
2915	>
2916	>	if (p == replacement) {  // detach pointers
2917	>	TreeNode<K,V> pp;
2918	>	if ((pp = p.parent) != null) {
2919	>	if (p == pp.left)
2920	>	pp.left = null;
2921	>	else if (p == pp.right)
2922	>	pp.right = null;
2923	>	p.parent = null;
2924	>	}
2925	>	}
2926	>	} finally {
2927	>	unlockRoot();
2928	>	}
2929	>	assert checkInvariants(root);
2930	>	return false;
2931	>	}
2932	>
2933	>	/* ------------------------------------------------------------ */
2934	>	// Red-black tree methods, all adapted from CLR
2935	>
2936	>	static <K,V> TreeNode<K,V> rotateLeft(TreeNode<K,V> root,
2937	>	TreeNode<K,V> p) {
2938	>	TreeNode<K,V> r, pp, rl;
2939	>	if (p != null && (r = p.right) != null) {
2940	>	if ((rl = p.right = r.left) != null)
2941	>	rl.parent = p;
2942	>	if ((pp = r.parent = p.parent) == null)
2943	>	(root = r).red = false;
2944	>	else if (pp.left == p)
2945	>	pp.left = r;
2946	>	else
2947	>	pp.right = r;
2948	>	r.left = p;
2949	>	p.parent = r;
2950	>	}
2951	>	return root;
2952	>	}
2953	>
2954	>	static <K,V> TreeNode<K,V> rotateRight(TreeNode<K,V> root,
2955	>	TreeNode<K,V> p) {
2956	>	TreeNode<K,V> l, pp, lr;
2957	>	if (p != null && (l = p.left) != null) {
2958	>	if ((lr = p.left = l.right) != null)
2959	>	lr.parent = p;
2960	>	if ((pp = l.parent = p.parent) == null)
2961	>	(root = l).red = false;
2962	>	else if (pp.right == p)
2963	>	pp.right = l;
2964	>	else
2965	>	pp.left = l;
2966	>	l.right = p;
2967	>	p.parent = l;
2968	>	}
2969	>	return root;
2970	>	}
2971	>
2972	>	static <K,V> TreeNode<K,V> balanceInsertion(TreeNode<K,V> root,
2973	>	TreeNode<K,V> x) {
2974	>	x.red = true;
2975	>	for (TreeNode<K,V> xp, xpp, xppl, xppr;;) {
2976	>	if ((xp = x.parent) == null) {
2977	>	x.red = false;
2978	>	return x;
2979	>	}
2980	>	else if (!xp.red || (xpp = xp.parent) == null)
2981	>	return root;
2982	>	if (xp == (xppl = xpp.left)) {
2983	>	if ((xppr = xpp.right) != null && xppr.red) {
2984	>	xppr.red = false;
2985	>	xp.red = false;
2986	>	xpp.red = true;
2987	>	x = xpp;
2988	>	}
2989	>	else {
2990	>	if (x == xp.right) {
2991	>	root = rotateLeft(root, x = xp);
2992	>	xpp = (xp = x.parent) == null ? null : xp.parent;
2993	>	}
2994	>	if (xp != null) {
2995	>	xp.red = false;
2996	>	if (xpp != null) {
2997	>	xpp.red = true;
2998	>	root = rotateRight(root, xpp);
2999	>	}
3000	>	}
3001	>	}
3002	>	}
3003	>	else {
3004	>	if (xppl != null && xppl.red) {
3005	>	xppl.red = false;
3006	>	xp.red = false;
3007	>	xpp.red = true;
3008	>	x = xpp;
3009	>	}
3010	>	else {
3011	>	if (x == xp.left) {
3012	>	root = rotateRight(root, x = xp);
3013	>	xpp = (xp = x.parent) == null ? null : xp.parent;
3014	>	}
3015	>	if (xp != null) {
3016	>	xp.red = false;
3017	>	if (xpp != null) {
3018	>	xpp.red = true;
3019	>	root = rotateLeft(root, xpp);
3020	>	}
3021	>	}
3022	>	}
3023	>	}
3024	>	}
3025	>	}
3026	>
3027	>	static <K,V> TreeNode<K,V> balanceDeletion(TreeNode<K,V> root,
3028	>	TreeNode<K,V> x) {
3029	>	for (TreeNode<K,V> xp, xpl, xpr;;) {
3030	>	if (x == null || x == root)
3031	>	return root;
3032	>	else if ((xp = x.parent) == null) {
3033	>	x.red = false;
3034	>	return x;
3035	>	}
3036	>	else if (x.red) {
3037	>	x.red = false;
3038	>	return root;
3039	>	}
3040	>	else if ((xpl = xp.left) == x) {
3041	>	if ((xpr = xp.right) != null && xpr.red) {
3042	>	xpr.red = false;
3043	>	xp.red = true;
3044	>	root = rotateLeft(root, xp);
3045	>	xpr = (xp = x.parent) == null ? null : xp.right;
3046	>	}
3047	>	if (xpr == null)
3048	>	x = xp;
3049	>	else {
3050	>	TreeNode<K,V> sl = xpr.left, sr = xpr.right;
3051	>	if ((sr == null || !sr.red) &&
3052	>	(sl == null || !sl.red)) {
3053	>	xpr.red = true;
3054	>	x = xp;
3055	>	}
3056	>	else {
3057	>	if (sr == null || !sr.red) {
3058	>	if (sl != null)
3059	>	sl.red = false;
3060	>	xpr.red = true;
3061	>	root = rotateRight(root, xpr);
3062	>	xpr = (xp = x.parent) == null ?
3063	>	null : xp.right;
3064	>	}
3065	>	if (xpr != null) {
3066	>	xpr.red = (xp == null) ? false : xp.red;
3067	>	if ((sr = xpr.right) != null)
3068	>	sr.red = false;
3069	>	}
3070	>	if (xp != null) {
3071	>	xp.red = false;
3072	>	root = rotateLeft(root, xp);
3073	>	}
3074	>	x = root;
3075	>	}
3076	>	}
3077	>	}
3078	>	else { // symmetric
3079	>	if (xpl != null && xpl.red) {
3080	>	xpl.red = false;
3081	>	xp.red = true;
3082	>	root = rotateRight(root, xp);
3083	>	xpl = (xp = x.parent) == null ? null : xp.left;
3084	>	}
3085	>	if (xpl == null)
3086	>	x = xp;
3087	>	else {
3088	>	TreeNode<K,V> sl = xpl.left, sr = xpl.right;
3089	>	if ((sl == null || !sl.red) &&
3090	>	(sr == null || !sr.red)) {
3091	>	xpl.red = true;
3092	>	x = xp;
3093	>	}
3094	>	else {
3095	>	if (sl == null || !sl.red) {
3096	>	if (sr != null)
3097	>	sr.red = false;
3098	>	xpl.red = true;
3099	>	root = rotateLeft(root, xpl);
3100	>	xpl = (xp = x.parent) == null ?
3101	>	null : xp.left;
3102	>	}
3103	>	if (xpl != null) {
3104	>	xpl.red = (xp == null) ? false : xp.red;
3105	>	if ((sl = xpl.left) != null)
3106	>	sl.red = false;
3107	>	}
3108	>	if (xp != null) {
3109	>	xp.red = false;
3110	>	root = rotateRight(root, xp);
3111	>	}
3112	>	x = root;
3113	>	}
3114	>	}
3115	>	}
3116	>	}
3117	>	}
3118	>
3119	>	/**
3120	>	* Recursive invariant check
3121	>	*/
3122	>	static <K,V> boolean checkInvariants(TreeNode<K,V> t) {
3123	>	TreeNode<K,V> tp = t.parent, tl = t.left, tr = t.right,
3124	>	tb = t.prev, tn = (TreeNode<K,V>)t.next;
3125	>	if (tb != null && tb.next != t)
3126	>	return false;
3127	>	if (tn != null && tn.prev != t)
3128	>	return false;
3129	>	if (tp != null && t != tp.left && t != tp.right)
3130	>	return false;
3131	>	if (tl != null && (tl.parent != t || tl.hash > t.hash))
3132	>	return false;
3133	>	if (tr != null && (tr.parent != t || tr.hash < t.hash))
3134	>	return false;
3135	>	if (t.red && tl != null && tl.red && tr != null && tr.red)
3136	>	return false;
3137	>	if (tl != null && !checkInvariants(tl))
3138	>	return false;
3139	>	if (tr != null && !checkInvariants(tr))
3140	>	return false;
3141	>	return true;
3142	>	}
3143	>
3144	>	private static final sun.misc.Unsafe U;
3145	>	private static final long LOCKSTATE;
3146	>	static {
3147	>	try {
3148	>	U = getUnsafe();
3149	>	Class<?> k = TreeBin.class;
3150	>	LOCKSTATE = U.objectFieldOffset
3151	>	(k.getDeclaredField("lockState"));
3152	>	} catch (Exception e) {
3153	>	throw new Error(e);
3154	>	}
3155	>	}
3156	>	}
3157	>
3158	>	/* ----------------Table Traversal -------------- */
3159	>
3160	>	/**
3161	>	* Records the table, its length, and current traversal index for a
3162	>	* traverser that must process a region of a forwarded table before
3163	>	* proceeding with current table.
3164	>	*/
3165	>	static final class TableStack<K,V> {
3166	>	int length;
3167	>	int index;
3168	>	Node<K,V>[] tab;
3169	>	TableStack<K,V> next;
3170	>	}
3171	>
3172	>	/**
3173	>	* Encapsulates traversal for methods such as containsValue; also
3174	>	* serves as a base class for other iterators and spliterators.
3175	>	*
3176	>	* Method advance visits once each still-valid node that was
3177	>	* reachable upon iterator construction. It might miss some that
3178	>	* were added to a bin after the bin was visited, which is OK wrt
3179	>	* consistency guarantees. Maintaining this property in the face
3180	>	* of possible ongoing resizes requires a fair amount of
3181	>	* bookkeeping state that is difficult to optimize away amidst
3182	>	* volatile accesses.  Even so, traversal maintains reasonable
3183	>	* throughput.
3184	>	*
3185	>	* Normally, iteration proceeds bin-by-bin traversing lists.
3186	>	* However, if the table has been resized, then all future steps
3187	>	* must traverse both the bin at the current index as well as at
3188	>	* (index + baseSize); and so on for further resizings. To
3189	>	* paranoically cope with potential sharing by users of iterators
3190	>	* across threads, iteration terminates if a bounds checks fails
3191	>	* for a table read.
3192	>	*/
3193	>	static class Traverser<K,V> {
3194	>	Node<K,V>[] tab;        // current table; updated if resized
3195	>	Node<K,V> next;         // the next entry to use
3196	>	TableStack<K,V> stack, spare; // to save/restore on ForwardingNodes
3197	>	int index;              // index of bin to use next
3198	>	int baseIndex;          // current index of initial table
3199	>	int baseLimit;          // index bound for initial table
3200	>	final int baseSize;     // initial table size
3201	>
3202	>	Traverser(Node<K,V>[] tab, int size, int index, int limit) {
3203	>	this.tab = tab;
3204	>	this.baseSize = size;
3205	>	this.baseIndex = this.index = index;
3206	>	this.baseLimit = limit;
3207	>	this.next = null;
3208	>	}
3209	>
3210	>	/**
3211	>	* Advances if possible, returning next valid node, or null if none.
3212	>	*/
3213	>	final Node<K,V> advance() {
3214	>	Node<K,V> e;
3215	>	if ((e = next) != null)
3216	>	e = e.next;
3217	>	for (;;) {
3218	>	Node<K,V>[] t; int i, n;  // must use locals in checks
3219	>	if (e != null)
3220	>	return next = e;
3221	>	if (baseIndex >= baseLimit || (t = tab) == null ||
3222	>	(n = t.length) <= (i = index) || i < 0)
3223	>	return next = null;
3224	>	if ((e = tabAt(t, i)) != null && e.hash < 0) {
3225	>	if (e instanceof ForwardingNode) {
3226	>	tab = ((ForwardingNode<K,V>)e).nextTable;
3227	>	e = null;
3228	>	pushState(t, i, n);
3229	>	continue;
3230	>	}
3231	>	else if (e instanceof TreeBin)
3232	>	e = ((TreeBin<K,V>)e).first;
3233	>	else
3234	>	e = null;
3235	>	}
3236	>	if (stack != null)
3237	>	recoverState(n);
3238	>	else if ((index = i + baseSize) >= n)
3239	>	index = ++baseIndex; // visit upper slots if present
3240	>	}
3241	>	}
3242	>
3243	>	/**
3244	>	* Saves traversal state upon encountering a forwarding node.
3245	>	*/
3246	>	private void pushState(Node<K,V>[] t, int i, int n) {
3247	>	TableStack<K,V> s = spare;  // reuse if possible
3248	>	if (s != null)
3249	>	spare = s.next;
3250	>	else
3251	>	s = new TableStack<K,V>();
3252	>	s.tab = t;
3253	>	s.length = n;
3254	>	s.index = i;
3255	>	s.next = stack;
3256	>	stack = s;
3257	>	}
3258	>
3259	>	/**
3260	>	* Possibly pops traversal state.
3261	>	*
3262	>	* @param n length of current table
3263	>	*/
3264	>	private void recoverState(int n) {
3265	>	TableStack<K,V> s; int len;
3266	>	while ((s = stack) != null && (index += (len = s.length)) >= n) {
3267	>	n = len;
3268	>	index = s.index;
3269	>	tab = s.tab;
3270	>	s.tab = null;
3271	>	TableStack<K,V> next = s.next;
3272	>	s.next = spare; // save for reuse
3273	>	stack = next;
3274	>	spare = s;
3275	>	}
3276	>	if (s == null && (index += baseSize) >= n)
3277	>	index = ++baseIndex;
3278	>	}
3279	>	}
3280	>
3281	>	/**
3282	>	* Base of key, value, and entry Iterators. Adds fields to
3283	>	* Traverser to support iterator.remove.
3284	>	*/
3285	>	static class BaseIterator<K,V> extends Traverser<K,V> {
3286	>	final ConcurrentHashMapV8<K,V> map;
3287	>	Node<K,V> lastReturned;
3288	>	BaseIterator(Node<K,V>[] tab, int size, int index, int limit,
3289	>	ConcurrentHashMapV8<K,V> map) {
3290	>	super(tab, size, index, limit);
3291	>	this.map = map;
3292	>	advance();
3293	>	}
3294	>
3295	>	public final boolean hasNext() { return next != null; }
3296	>	public final boolean hasMoreElements() { return next != null; }
3297	>
3298	>	public final void remove() {
3299	>	Node<K,V> p;
3300	>	if ((p = lastReturned) == null)
3301		throw new IllegalStateException();
3302	<	return new ValueIterator<K,V>(this, false);
3302	>	lastReturned = null;
3303	>	map.replaceNode(p.key, null, null);
3304		}
3305	+	}
3306
3307	<	@SuppressWarnings("unchecked")
3308	<	public final V next() {
3309	<	Object v;
3310	<	if ((v = nextVal) == null && (v = advance()) == null)
3307	>	static final class KeyIterator<K,V> extends BaseIterator<K,V>
3308	>	implements Iterator<K>, Enumeration<K> {
3309	>	KeyIterator(Node<K,V>[] tab, int index, int size, int limit,
3310	>	ConcurrentHashMapV8<K,V> map) {
3311	>	super(tab, index, size, limit, map);
3312	>	}
3313	>
3314	>	public final K next() {
3315	>	Node<K,V> p;
3316	>	if ((p = next) == null)
3317		throw new NoSuchElementException();
3318	<	nextVal = null;
3319	<	return (V) v;
3318	>	K k = p.key;
3319	>	lastReturned = p;
3320	>	advance();
3321	>	return k;
3322		}
3323
3324	<	public final V nextElement() { return next(); }
3324	>	public final K nextElement() { return next(); }
3325		}
3326
3327	<	static final class EntryIterator<K,V> extends InternalIterator<K,V>
3328	<	implements Spliterator<Map.Entry<K,V>> {
3329	<	EntryIterator(ConcurrentHashMapV8<K, V> map) { super(map); }
3330	<	EntryIterator(InternalIterator<K,V> it, boolean split) {
3331	<	super(it, split);
3327	>	static final class ValueIterator<K,V> extends BaseIterator<K,V>
3328	>	implements Iterator<V>, Enumeration<V> {
3329	>	ValueIterator(Node<K,V>[] tab, int index, int size, int limit,
3330	>	ConcurrentHashMapV8<K,V> map) {
3331	>	super(tab, index, size, limit, map);
3332		}
3333	<	public EntryIterator<K,V> split() {
3334	<	if (last != null || (next != null && nextVal == null))
3335	<	throw new IllegalStateException();
3336	<	return new EntryIterator<K,V>(this, true);
3333	>
3334	>	public final V next() {
3335	>	Node<K,V> p;
3336	>	if ((p = next) == null)
3337	>	throw new NoSuchElementException();
3338	>	V v = p.val;
3339	>	lastReturned = p;
3340	>	advance();
3341	>	return v;
3342		}
3343	<	public EntryIterator<K,V> clone() {
3344	<	if (last != null || (next != null && nextVal == null))
3345	<	throw new IllegalStateException();
3346	<	return new EntryIterator<K,V>(this, false);
3343	>
3344	>	public final V nextElement() { return next(); }
3345	>	}
3346	>
3347	>	static final class EntryIterator<K,V> extends BaseIterator<K,V>
3348	>	implements Iterator<Map.Entry<K,V>> {
3349	>	EntryIterator(Node<K,V>[] tab, int index, int size, int limit,
3350	>	ConcurrentHashMapV8<K,V> map) {
3351	>	super(tab, index, size, limit, map);
3352		}
3353
2904	–	@SuppressWarnings("unchecked")
3354		public final Map.Entry<K,V> next() {
3355	<	Object v;
3356	<	if ((v = nextVal) == null && (v = advance()) == null)
3355	>	Node<K,V> p;
3356	>	if ((p = next) == null)
3357		throw new NoSuchElementException();
3358	<	Object k = nextKey;
3359	<	nextVal = null;
3360	<	return new MapEntry<K,V>((K)k, (V)v, map);
3358	>	K k = p.key;
3359	>	V v = p.val;
3360	>	lastReturned = p;
3361	>	advance();
3362	>	return new MapEntry<K,V>(k, v, map);
3363		}
3364		}
3365
3366		/**
3367	<	* Exported Entry for iterators
3367	>	* Exported Entry for EntryIterator
3368		*/
3369	<	static final class MapEntry<K,V> implements Map.Entry<K, V> {
3369	>	static final class MapEntry<K,V> implements Map.Entry<K,V> {
3370		final K key; // non-null
3371		V val;       // non-null
3372	<	final ConcurrentHashMapV8<K, V> map;
3373	<	MapEntry(K key, V val, ConcurrentHashMapV8<K, V> map) {
3372	>	final ConcurrentHashMapV8<K,V> map;
3373	>	MapEntry(K key, V val, ConcurrentHashMapV8<K,V> map) {
3374		this.key = key;
3375		this.val = val;
3376		this.map = map;
3377		}
3378	<	public final K getKey()       { return key; }
3379	<	public final V getValue()     { return val; }
3380	<	public final int hashCode()   { return key.hashCode() ^ val.hashCode(); }
3381	<	public final String toString(){ return key + "=" + val; }
3378	>	public K getKey()        { return key; }
3379	>	public V getValue()      { return val; }
3380	>	public int hashCode()    { return key.hashCode() ^ val.hashCode(); }
3381	>	public String toString() { return key + "=" + val; }
3382
3383	<	public final boolean equals(Object o) {
3383	>	public boolean equals(Object o) {
3384		Object k, v; Map.Entry<?,?> e;
3385		return ((o instanceof Map.Entry) &&
3386		(k = (e = (Map.Entry<?,?>)o).getKey()) != null &&
#	Line 2940 | Line 3391 | public class ConcurrentHashMapV8<K, V>
3391
3392		/**
3393		* Sets our entry's value and writes through to the map. The
3394	<	* value to return is somewhat arbitrary here. Since a we do
3395	<	* not necessarily track asynchronous changes, the most recent
3394	>	* value to return is somewhat arbitrary here. Since we do not
3395	>	* necessarily track asynchronous changes, the most recent
3396		* "previous" value could be different from what we return (or
3397	<	* could even have been removed in which case the put will
3397	>	* could even have been removed, in which case the put will
3398		* re-establish). We do not and cannot guarantee more.
3399		*/
3400	<	public final V setValue(V value) {
3400	>	public V setValue(V value) {
3401		if (value == null) throw new NullPointerException();
3402		V v = val;
3403		val = value;
#	Line 2955 | Line 3406 | public class ConcurrentHashMapV8<K, V>
3406		}
3407		}
3408
3409	+	static final class KeySpliterator<K,V> extends Traverser<K,V>
3410	+	implements ConcurrentHashMapSpliterator<K> {
3411	+	long est;               // size estimate
3412	+	KeySpliterator(Node<K,V>[] tab, int size, int index, int limit,
3413	+	long est) {
3414	+	super(tab, size, index, limit);
3415	+	this.est = est;
3416	+	}
3417	+
3418	+	public ConcurrentHashMapSpliterator<K> trySplit() {
3419	+	int i, f, h;
3420	+	return (h = ((i = baseIndex) + (f = baseLimit)) >>> 1) <= i ? null :
3421	+	new KeySpliterator<K,V>(tab, baseSize, baseLimit = h,
3422	+	f, est >>>= 1);
3423	+	}
3424	+
3425	+	public void forEachRemaining(Action<? super K> action) {
3426	+	if (action == null) throw new NullPointerException();
3427	+	for (Node<K,V> p; (p = advance()) != null;)
3428	+	action.apply(p.key);
3429	+	}
3430	+
3431	+	public boolean tryAdvance(Action<? super K> action) {
3432	+	if (action == null) throw new NullPointerException();
3433	+	Node<K,V> p;
3434	+	if ((p = advance()) == null)
3435	+	return false;
3436	+	action.apply(p.key);
3437	+	return true;
3438	+	}
3439	+
3440	+	public long estimateSize() { return est; }
3441	+
3442	+	}
3443	+
3444	+	static final class ValueSpliterator<K,V> extends Traverser<K,V>
3445	+	implements ConcurrentHashMapSpliterator<V> {
3446	+	long est;               // size estimate
3447	+	ValueSpliterator(Node<K,V>[] tab, int size, int index, int limit,
3448	+	long est) {
3449	+	super(tab, size, index, limit);
3450	+	this.est = est;
3451	+	}
3452	+
3453	+	public ConcurrentHashMapSpliterator<V> trySplit() {
3454	+	int i, f, h;
3455	+	return (h = ((i = baseIndex) + (f = baseLimit)) >>> 1) <= i ? null :
3456	+	new ValueSpliterator<K,V>(tab, baseSize, baseLimit = h,
3457	+	f, est >>>= 1);
3458	+	}
3459	+
3460	+	public void forEachRemaining(Action<? super V> action) {
3461	+	if (action == null) throw new NullPointerException();
3462	+	for (Node<K,V> p; (p = advance()) != null;)
3463	+	action.apply(p.val);
3464	+	}
3465	+
3466	+	public boolean tryAdvance(Action<? super V> action) {
3467	+	if (action == null) throw new NullPointerException();
3468	+	Node<K,V> p;
3469	+	if ((p = advance()) == null)
3470	+	return false;
3471	+	action.apply(p.val);
3472	+	return true;
3473	+	}
3474	+
3475	+	public long estimateSize() { return est; }
3476	+
3477	+	}
3478	+
3479	+	static final class EntrySpliterator<K,V> extends Traverser<K,V>
3480	+	implements ConcurrentHashMapSpliterator<Map.Entry<K,V>> {
3481	+	final ConcurrentHashMapV8<K,V> map; // To export MapEntry
3482	+	long est;               // size estimate
3483	+	EntrySpliterator(Node<K,V>[] tab, int size, int index, int limit,
3484	+	long est, ConcurrentHashMapV8<K,V> map) {
3485	+	super(tab, size, index, limit);
3486	+	this.map = map;
3487	+	this.est = est;
3488	+	}
3489	+
3490	+	public ConcurrentHashMapSpliterator<Map.Entry<K,V>> trySplit() {
3491	+	int i, f, h;
3492	+	return (h = ((i = baseIndex) + (f = baseLimit)) >>> 1) <= i ? null :
3493	+	new EntrySpliterator<K,V>(tab, baseSize, baseLimit = h,
3494	+	f, est >>>= 1, map);
3495	+	}
3496	+
3497	+	public void forEachRemaining(Action<? super Map.Entry<K,V>> action) {
3498	+	if (action == null) throw new NullPointerException();
3499	+	for (Node<K,V> p; (p = advance()) != null; )
3500	+	action.apply(new MapEntry<K,V>(p.key, p.val, map));
3501	+	}
3502	+
3503	+	public boolean tryAdvance(Action<? super Map.Entry<K,V>> action) {
3504	+	if (action == null) throw new NullPointerException();
3505	+	Node<K,V> p;
3506	+	if ((p = advance()) == null)
3507	+	return false;
3508	+	action.apply(new MapEntry<K,V>(p.key, p.val, map));
3509	+	return true;
3510	+	}
3511	+
3512	+	public long estimateSize() { return est; }
3513	+
3514	+	}
3515	+
3516	+	// Parallel bulk operations
3517	+
3518	+	/**
3519	+	* Computes initial batch value for bulk tasks. The returned value
3520	+	* is approximately exp2 of the number of times (minus one) to
3521	+	* split task by two before executing leaf action. This value is
3522	+	* faster to compute and more convenient to use as a guide to
3523	+	* splitting than is the depth, since it is used while dividing by
3524	+	* two anyway.
3525	+	*/
3526	+	final int batchFor(long b) {
3527	+	long n;
3528	+	if (b == Long.MAX_VALUE || (n = sumCount()) <= 1L || n < b)
3529	+	return 0;
3530	+	int sp = ForkJoinPool.getCommonPoolParallelism() << 2; // slack of 4
3531	+	return (b <= 0L || (n /= b) >= sp) ? sp : (int)n;
3532	+	}
3533	+
3534	+	/**
3535	+	* Performs the given action for each (key, value).
3536	+	*
3537	+	* @param parallelismThreshold the (estimated) number of elements
3538	+	* needed for this operation to be executed in parallel
3539	+	* @param action the action
3540	+	* @since 1.8
3541	+	*/
3542	+	public void forEach(long parallelismThreshold,
3543	+	BiAction<? super K,? super V> action) {
3544	+	if (action == null) throw new NullPointerException();
3545	+	new ForEachMappingTask<K,V>
3546	+	(null, batchFor(parallelismThreshold), 0, 0, table,
3547	+	action).invoke();
3548	+	}
3549	+
3550	+	/**
3551	+	* Performs the given action for each non-null transformation
3552	+	* of each (key, value).
3553	+	*
3554	+	* @param parallelismThreshold the (estimated) number of elements
3555	+	* needed for this operation to be executed in parallel
3556	+	* @param transformer a function returning the transformation
3557	+	* for an element, or null if there is no transformation (in
3558	+	* which case the action is not applied)
3559	+	* @param action the action
3560	+	* @since 1.8
3561	+	*/
3562	+	public <U> void forEach(long parallelismThreshold,
3563	+	BiFun<? super K, ? super V, ? extends U> transformer,
3564	+	Action<? super U> action) {
3565	+	if (transformer == null || action == null)
3566	+	throw new NullPointerException();
3567	+	new ForEachTransformedMappingTask<K,V,U>
3568	+	(null, batchFor(parallelismThreshold), 0, 0, table,
3569	+	transformer, action).invoke();
3570	+	}
3571	+
3572	+	/**
3573	+	* Returns a non-null result from applying the given search
3574	+	* function on each (key, value), or null if none.  Upon
3575	+	* success, further element processing is suppressed and the
3576	+	* results of any other parallel invocations of the search
3577	+	* function are ignored.
3578	+	*
3579	+	* @param parallelismThreshold the (estimated) number of elements
3580	+	* needed for this operation to be executed in parallel
3581	+	* @param searchFunction a function returning a non-null
3582	+	* result on success, else null
3583	+	* @return a non-null result from applying the given search
3584	+	* function on each (key, value), or null if none
3585	+	* @since 1.8
3586	+	*/
3587	+	public <U> U search(long parallelismThreshold,
3588	+	BiFun<? super K, ? super V, ? extends U> searchFunction) {
3589	+	if (searchFunction == null) throw new NullPointerException();
3590	+	return new SearchMappingsTask<K,V,U>
3591	+	(null, batchFor(parallelismThreshold), 0, 0, table,
3592	+	searchFunction, new AtomicReference<U>()).invoke();
3593	+	}
3594	+
3595	+	/**
3596	+	* Returns the result of accumulating the given transformation
3597	+	* of all (key, value) pairs using the given reducer to
3598	+	* combine values, or null if none.
3599	+	*
3600	+	* @param parallelismThreshold the (estimated) number of elements
3601	+	* needed for this operation to be executed in parallel
3602	+	* @param transformer a function returning the transformation
3603	+	* for an element, or null if there is no transformation (in
3604	+	* which case it is not combined)
3605	+	* @param reducer a commutative associative combining function
3606	+	* @return the result of accumulating the given transformation
3607	+	* of all (key, value) pairs
3608	+	* @since 1.8
3609	+	*/
3610	+	public <U> U reduce(long parallelismThreshold,
3611	+	BiFun<? super K, ? super V, ? extends U> transformer,
3612	+	BiFun<? super U, ? super U, ? extends U> reducer) {
3613	+	if (transformer == null || reducer == null)
3614	+	throw new NullPointerException();
3615	+	return new MapReduceMappingsTask<K,V,U>
3616	+	(null, batchFor(parallelismThreshold), 0, 0, table,
3617	+	null, transformer, reducer).invoke();
3618	+	}
3619	+
3620	+	/**
3621	+	* Returns the result of accumulating the given transformation
3622	+	* of all (key, value) pairs using the given reducer to
3623	+	* combine values, and the given basis as an identity value.
3624	+	*
3625	+	* @param parallelismThreshold the (estimated) number of elements
3626	+	* needed for this operation to be executed in parallel
3627	+	* @param transformer a function returning the transformation
3628	+	* for an element
3629	+	* @param basis the identity (initial default value) for the reduction
3630	+	* @param reducer a commutative associative combining function
3631	+	* @return the result of accumulating the given transformation
3632	+	* of all (key, value) pairs
3633	+	* @since 1.8
3634	+	*/
3635	+	public double reduceToDouble(long parallelismThreshold,
3636	+	ObjectByObjectToDouble<? super K, ? super V> transformer,
3637	+	double basis,
3638	+	DoubleByDoubleToDouble reducer) {
3639	+	if (transformer == null || reducer == null)
3640	+	throw new NullPointerException();
3641	+	return new MapReduceMappingsToDoubleTask<K,V>
3642	+	(null, batchFor(parallelismThreshold), 0, 0, table,
3643	+	null, transformer, basis, reducer).invoke();
3644	+	}
3645	+
3646	+	/**
3647	+	* Returns the result of accumulating the given transformation
3648	+	* of all (key, value) pairs using the given reducer to
3649	+	* combine values, and the given basis as an identity value.
3650	+	*
3651	+	* @param parallelismThreshold the (estimated) number of elements
3652	+	* needed for this operation to be executed in parallel
3653	+	* @param transformer a function returning the transformation
3654	+	* for an element
3655	+	* @param basis the identity (initial default value) for the reduction
3656	+	* @param reducer a commutative associative combining function
3657	+	* @return the result of accumulating the given transformation
3658	+	* of all (key, value) pairs
3659	+	* @since 1.8
3660	+	*/
3661	+	public long reduceToLong(long parallelismThreshold,
3662	+	ObjectByObjectToLong<? super K, ? super V> transformer,
3663	+	long basis,
3664	+	LongByLongToLong reducer) {
3665	+	if (transformer == null || reducer == null)
3666	+	throw new NullPointerException();
3667	+	return new MapReduceMappingsToLongTask<K,V>
3668	+	(null, batchFor(parallelismThreshold), 0, 0, table,
3669	+	null, transformer, basis, reducer).invoke();
3670	+	}
3671	+
3672	+	/**
3673	+	* Returns the result of accumulating the given transformation
3674	+	* of all (key, value) pairs using the given reducer to
3675	+	* combine values, and the given basis as an identity value.
3676	+	*
3677	+	* @param parallelismThreshold the (estimated) number of elements
3678	+	* needed for this operation to be executed in parallel
3679	+	* @param transformer a function returning the transformation
3680	+	* for an element
3681	+	* @param basis the identity (initial default value) for the reduction
3682	+	* @param reducer a commutative associative combining function
3683	+	* @return the result of accumulating the given transformation
3684	+	* of all (key, value) pairs
3685	+	* @since 1.8
3686	+	*/
3687	+	public int reduceToInt(long parallelismThreshold,
3688	+	ObjectByObjectToInt<? super K, ? super V> transformer,
3689	+	int basis,
3690	+	IntByIntToInt reducer) {
3691	+	if (transformer == null || reducer == null)
3692	+	throw new NullPointerException();
3693	+	return new MapReduceMappingsToIntTask<K,V>
3694	+	(null, batchFor(parallelismThreshold), 0, 0, table,
3695	+	null, transformer, basis, reducer).invoke();
3696	+	}
3697	+
3698	+	/**
3699	+	* Performs the given action for each key.
3700	+	*
3701	+	* @param parallelismThreshold the (estimated) number of elements
3702	+	* needed for this operation to be executed in parallel
3703	+	* @param action the action
3704	+	* @since 1.8
3705	+	*/
3706	+	public void forEachKey(long parallelismThreshold,
3707	+	Action<? super K> action) {
3708	+	if (action == null) throw new NullPointerException();
3709	+	new ForEachKeyTask<K,V>
3710	+	(null, batchFor(parallelismThreshold), 0, 0, table,
3711	+	action).invoke();
3712	+	}
3713	+
3714	+	/**
3715	+	* Performs the given action for each non-null transformation
3716	+	* of each key.
3717	+	*
3718	+	* @param parallelismThreshold the (estimated) number of elements
3719	+	* needed for this operation to be executed in parallel
3720	+	* @param transformer a function returning the transformation
3721	+	* for an element, or null if there is no transformation (in
3722	+	* which case the action is not applied)
3723	+	* @param action the action
3724	+	* @since 1.8
3725	+	*/
3726	+	public <U> void forEachKey(long parallelismThreshold,
3727	+	Fun<? super K, ? extends U> transformer,
3728	+	Action<? super U> action) {
3729	+	if (transformer == null || action == null)
3730	+	throw new NullPointerException();
3731	+	new ForEachTransformedKeyTask<K,V,U>
3732	+	(null, batchFor(parallelismThreshold), 0, 0, table,
3733	+	transformer, action).invoke();
3734	+	}
3735	+
3736	+	/**
3737	+	* Returns a non-null result from applying the given search
3738	+	* function on each key, or null if none. Upon success,
3739	+	* further element processing is suppressed and the results of
3740	+	* any other parallel invocations of the search function are
3741	+	* ignored.
3742	+	*
3743	+	* @param parallelismThreshold the (estimated) number of elements
3744	+	* needed for this operation to be executed in parallel
3745	+	* @param searchFunction a function returning a non-null
3746	+	* result on success, else null
3747	+	* @return a non-null result from applying the given search
3748	+	* function on each key, or null if none
3749	+	* @since 1.8
3750	+	*/
3751	+	public <U> U searchKeys(long parallelismThreshold,
3752	+	Fun<? super K, ? extends U> searchFunction) {
3753	+	if (searchFunction == null) throw new NullPointerException();
3754	+	return new SearchKeysTask<K,V,U>
3755	+	(null, batchFor(parallelismThreshold), 0, 0, table,
3756	+	searchFunction, new AtomicReference<U>()).invoke();
3757	+	}
3758	+
3759	+	/**
3760	+	* Returns the result of accumulating all keys using the given
3761	+	* reducer to combine values, or null if none.
3762	+	*
3763	+	* @param parallelismThreshold the (estimated) number of elements
3764	+	* needed for this operation to be executed in parallel
3765	+	* @param reducer a commutative associative combining function
3766	+	* @return the result of accumulating all keys using the given
3767	+	* reducer to combine values, or null if none
3768	+	* @since 1.8
3769	+	*/
3770	+	public K reduceKeys(long parallelismThreshold,
3771	+	BiFun<? super K, ? super K, ? extends K> reducer) {
3772	+	if (reducer == null) throw new NullPointerException();
3773	+	return new ReduceKeysTask<K,V>
3774	+	(null, batchFor(parallelismThreshold), 0, 0, table,
3775	+	null, reducer).invoke();
3776	+	}
3777	+
3778	+	/**
3779	+	* Returns the result of accumulating the given transformation
3780	+	* of all keys using the given reducer to combine values, or
3781	+	* null if none.
3782	+	*
3783	+	* @param parallelismThreshold the (estimated) number of elements
3784	+	* needed for this operation to be executed in parallel
3785	+	* @param transformer a function returning the transformation
3786	+	* for an element, or null if there is no transformation (in
3787	+	* which case it is not combined)
3788	+	* @param reducer a commutative associative combining function
3789	+	* @return the result of accumulating the given transformation
3790	+	* of all keys
3791	+	* @since 1.8
3792	+	*/
3793	+	public <U> U reduceKeys(long parallelismThreshold,
3794	+	Fun<? super K, ? extends U> transformer,
3795	+	BiFun<? super U, ? super U, ? extends U> reducer) {
3796	+	if (transformer == null || reducer == null)
3797	+	throw new NullPointerException();
3798	+	return new MapReduceKeysTask<K,V,U>
3799	+	(null, batchFor(parallelismThreshold), 0, 0, table,
3800	+	null, transformer, reducer).invoke();
3801	+	}
3802	+
3803	+	/**
3804	+	* Returns the result of accumulating the given transformation
3805	+	* of all keys using the given reducer to combine values, and
3806	+	* the given basis as an identity value.
3807	+	*
3808	+	* @param parallelismThreshold the (estimated) number of elements
3809	+	* needed for this operation to be executed in parallel
3810	+	* @param transformer a function returning the transformation
3811	+	* for an element
3812	+	* @param basis the identity (initial default value) for the reduction
3813	+	* @param reducer a commutative associative combining function
3814	+	* @return the result of accumulating the given transformation
3815	+	* of all keys
3816	+	* @since 1.8
3817	+	*/
3818	+	public double reduceKeysToDouble(long parallelismThreshold,
3819	+	ObjectToDouble<? super K> transformer,
3820	+	double basis,
3821	+	DoubleByDoubleToDouble reducer) {
3822	+	if (transformer == null || reducer == null)
3823	+	throw new NullPointerException();
3824	+	return new MapReduceKeysToDoubleTask<K,V>
3825	+	(null, batchFor(parallelismThreshold), 0, 0, table,
3826	+	null, transformer, basis, reducer).invoke();
3827	+	}
3828	+
3829	+	/**
3830	+	* Returns the result of accumulating the given transformation
3831	+	* of all keys using the given reducer to combine values, and
3832	+	* the given basis as an identity value.
3833	+	*
3834	+	* @param parallelismThreshold the (estimated) number of elements
3835	+	* needed for this operation to be executed in parallel
3836	+	* @param transformer a function returning the transformation
3837	+	* for an element
3838	+	* @param basis the identity (initial default value) for the reduction
3839	+	* @param reducer a commutative associative combining function
3840	+	* @return the result of accumulating the given transformation
3841	+	* of all keys
3842	+	* @since 1.8
3843	+	*/
3844	+	public long reduceKeysToLong(long parallelismThreshold,
3845	+	ObjectToLong<? super K> transformer,
3846	+	long basis,
3847	+	LongByLongToLong reducer) {
3848	+	if (transformer == null || reducer == null)
3849	+	throw new NullPointerException();
3850	+	return new MapReduceKeysToLongTask<K,V>
3851	+	(null, batchFor(parallelismThreshold), 0, 0, table,
3852	+	null, transformer, basis, reducer).invoke();
3853	+	}
3854	+
3855	+	/**
3856	+	* Returns the result of accumulating the given transformation
3857	+	* of all keys using the given reducer to combine values, and
3858	+	* the given basis as an identity value.
3859	+	*
3860	+	* @param parallelismThreshold the (estimated) number of elements
3861	+	* needed for this operation to be executed in parallel
3862	+	* @param transformer a function returning the transformation
3863	+	* for an element
3864	+	* @param basis the identity (initial default value) for the reduction
3865	+	* @param reducer a commutative associative combining function
3866	+	* @return the result of accumulating the given transformation
3867	+	* of all keys
3868	+	* @since 1.8
3869	+	*/
3870	+	public int reduceKeysToInt(long parallelismThreshold,
3871	+	ObjectToInt<? super K> transformer,
3872	+	int basis,
3873	+	IntByIntToInt reducer) {
3874	+	if (transformer == null || reducer == null)
3875	+	throw new NullPointerException();
3876	+	return new MapReduceKeysToIntTask<K,V>
3877	+	(null, batchFor(parallelismThreshold), 0, 0, table,
3878	+	null, transformer, basis, reducer).invoke();
3879	+	}
3880	+
3881	+	/**
3882	+	* Performs the given action for each value.
3883	+	*
3884	+	* @param parallelismThreshold the (estimated) number of elements
3885	+	* needed for this operation to be executed in parallel
3886	+	* @param action the action
3887	+	* @since 1.8
3888	+	*/
3889	+	public void forEachValue(long parallelismThreshold,
3890	+	Action<? super V> action) {
3891	+	if (action == null)
3892	+	throw new NullPointerException();
3893	+	new ForEachValueTask<K,V>
3894	+	(null, batchFor(parallelismThreshold), 0, 0, table,
3895	+	action).invoke();
3896	+	}
3897	+
3898	+	/**
3899	+	* Performs the given action for each non-null transformation
3900	+	* of each value.
3901	+	*
3902	+	* @param parallelismThreshold the (estimated) number of elements
3903	+	* needed for this operation to be executed in parallel
3904	+	* @param transformer a function returning the transformation
3905	+	* for an element, or null if there is no transformation (in
3906	+	* which case the action is not applied)
3907	+	* @param action the action
3908	+	* @since 1.8
3909	+	*/
3910	+	public <U> void forEachValue(long parallelismThreshold,
3911	+	Fun<? super V, ? extends U> transformer,
3912	+	Action<? super U> action) {
3913	+	if (transformer == null || action == null)
3914	+	throw new NullPointerException();
3915	+	new ForEachTransformedValueTask<K,V,U>
3916	+	(null, batchFor(parallelismThreshold), 0, 0, table,
3917	+	transformer, action).invoke();
3918	+	}
3919	+
3920	+	/**
3921	+	* Returns a non-null result from applying the given search
3922	+	* function on each value, or null if none.  Upon success,
3923	+	* further element processing is suppressed and the results of
3924	+	* any other parallel invocations of the search function are
3925	+	* ignored.
3926	+	*
3927	+	* @param parallelismThreshold the (estimated) number of elements
3928	+	* needed for this operation to be executed in parallel
3929	+	* @param searchFunction a function returning a non-null
3930	+	* result on success, else null
3931	+	* @return a non-null result from applying the given search
3932	+	* function on each value, or null if none
3933	+	* @since 1.8
3934	+	*/
3935	+	public <U> U searchValues(long parallelismThreshold,
3936	+	Fun<? super V, ? extends U> searchFunction) {
3937	+	if (searchFunction == null) throw new NullPointerException();
3938	+	return new SearchValuesTask<K,V,U>
3939	+	(null, batchFor(parallelismThreshold), 0, 0, table,
3940	+	searchFunction, new AtomicReference<U>()).invoke();
3941	+	}
3942	+
3943	+	/**
3944	+	* Returns the result of accumulating all values using the
3945	+	* given reducer to combine values, or null if none.
3946	+	*
3947	+	* @param parallelismThreshold the (estimated) number of elements
3948	+	* needed for this operation to be executed in parallel
3949	+	* @param reducer a commutative associative combining function
3950	+	* @return the result of accumulating all values
3951	+	* @since 1.8
3952	+	*/
3953	+	public V reduceValues(long parallelismThreshold,
3954	+	BiFun<? super V, ? super V, ? extends V> reducer) {
3955	+	if (reducer == null) throw new NullPointerException();
3956	+	return new ReduceValuesTask<K,V>
3957	+	(null, batchFor(parallelismThreshold), 0, 0, table,
3958	+	null, reducer).invoke();
3959	+	}
3960	+
3961	+	/**
3962	+	* Returns the result of accumulating the given transformation
3963	+	* of all values using the given reducer to combine values, or
3964	+	* null if none.
3965	+	*
3966	+	* @param parallelismThreshold the (estimated) number of elements
3967	+	* needed for this operation to be executed in parallel
3968	+	* @param transformer a function returning the transformation
3969	+	* for an element, or null if there is no transformation (in
3970	+	* which case it is not combined)
3971	+	* @param reducer a commutative associative combining function
3972	+	* @return the result of accumulating the given transformation
3973	+	* of all values
3974	+	* @since 1.8
3975	+	*/
3976	+	public <U> U reduceValues(long parallelismThreshold,
3977	+	Fun<? super V, ? extends U> transformer,
3978	+	BiFun<? super U, ? super U, ? extends U> reducer) {
3979	+	if (transformer == null || reducer == null)
3980	+	throw new NullPointerException();
3981	+	return new MapReduceValuesTask<K,V,U>
3982	+	(null, batchFor(parallelismThreshold), 0, 0, table,
3983	+	null, transformer, reducer).invoke();
3984	+	}
3985	+
3986	+	/**
3987	+	* Returns the result of accumulating the given transformation
3988	+	* of all values using the given reducer to combine values,
3989	+	* and the given basis as an identity value.
3990	+	*
3991	+	* @param parallelismThreshold the (estimated) number of elements
3992	+	* needed for this operation to be executed in parallel
3993	+	* @param transformer a function returning the transformation
3994	+	* for an element
3995	+	* @param basis the identity (initial default value) for the reduction
3996	+	* @param reducer a commutative associative combining function
3997	+	* @return the result of accumulating the given transformation
3998	+	* of all values
3999	+	* @since 1.8
4000	+	*/
4001	+	public double reduceValuesToDouble(long parallelismThreshold,
4002	+	ObjectToDouble<? super V> transformer,
4003	+	double basis,
4004	+	DoubleByDoubleToDouble reducer) {
4005	+	if (transformer == null || reducer == null)
4006	+	throw new NullPointerException();
4007	+	return new MapReduceValuesToDoubleTask<K,V>
4008	+	(null, batchFor(parallelismThreshold), 0, 0, table,
4009	+	null, transformer, basis, reducer).invoke();
4010	+	}
4011	+
4012	+	/**
4013	+	* Returns the result of accumulating the given transformation
4014	+	* of all values using the given reducer to combine values,
4015	+	* and the given basis as an identity value.
4016	+	*
4017	+	* @param parallelismThreshold the (estimated) number of elements
4018	+	* needed for this operation to be executed in parallel
4019	+	* @param transformer a function returning the transformation
4020	+	* for an element
4021	+	* @param basis the identity (initial default value) for the reduction
4022	+	* @param reducer a commutative associative combining function
4023	+	* @return the result of accumulating the given transformation
4024	+	* of all values
4025	+	* @since 1.8
4026	+	*/
4027	+	public long reduceValuesToLong(long parallelismThreshold,
4028	+	ObjectToLong<? super V> transformer,
4029	+	long basis,
4030	+	LongByLongToLong reducer) {
4031	+	if (transformer == null || reducer == null)
4032	+	throw new NullPointerException();
4033	+	return new MapReduceValuesToLongTask<K,V>
4034	+	(null, batchFor(parallelismThreshold), 0, 0, table,
4035	+	null, transformer, basis, reducer).invoke();
4036	+	}
4037	+
4038	+	/**
4039	+	* Returns the result of accumulating the given transformation
4040	+	* of all values using the given reducer to combine values,
4041	+	* and the given basis as an identity value.
4042	+	*
4043	+	* @param parallelismThreshold the (estimated) number of elements
4044	+	* needed for this operation to be executed in parallel
4045	+	* @param transformer a function returning the transformation
4046	+	* for an element
4047	+	* @param basis the identity (initial default value) for the reduction
4048	+	* @param reducer a commutative associative combining function
4049	+	* @return the result of accumulating the given transformation
4050	+	* of all values
4051	+	* @since 1.8
4052	+	*/
4053	+	public int reduceValuesToInt(long parallelismThreshold,
4054	+	ObjectToInt<? super V> transformer,
4055	+	int basis,
4056	+	IntByIntToInt reducer) {
4057	+	if (transformer == null || reducer == null)
4058	+	throw new NullPointerException();
4059	+	return new MapReduceValuesToIntTask<K,V>
4060	+	(null, batchFor(parallelismThreshold), 0, 0, table,
4061	+	null, transformer, basis, reducer).invoke();
4062	+	}
4063	+
4064	+	/**
4065	+	* Performs the given action for each entry.
4066	+	*
4067	+	* @param parallelismThreshold the (estimated) number of elements
4068	+	* needed for this operation to be executed in parallel
4069	+	* @param action the action
4070	+	* @since 1.8
4071	+	*/
4072	+	public void forEachEntry(long parallelismThreshold,
4073	+	Action<? super Map.Entry<K,V>> action) {
4074	+	if (action == null) throw new NullPointerException();
4075	+	new ForEachEntryTask<K,V>(null, batchFor(parallelismThreshold), 0, 0, table,
4076	+	action).invoke();
4077	+	}
4078	+
4079	+	/**
4080	+	* Performs the given action for each non-null transformation
4081	+	* of each entry.
4082	+	*
4083	+	* @param parallelismThreshold the (estimated) number of elements
4084	+	* needed for this operation to be executed in parallel
4085	+	* @param transformer a function returning the transformation
4086	+	* for an element, or null if there is no transformation (in
4087	+	* which case the action is not applied)
4088	+	* @param action the action
4089	+	* @since 1.8
4090	+	*/
4091	+	public <U> void forEachEntry(long parallelismThreshold,
4092	+	Fun<Map.Entry<K,V>, ? extends U> transformer,
4093	+	Action<? super U> action) {
4094	+	if (transformer == null || action == null)
4095	+	throw new NullPointerException();
4096	+	new ForEachTransformedEntryTask<K,V,U>
4097	+	(null, batchFor(parallelismThreshold), 0, 0, table,
4098	+	transformer, action).invoke();
4099	+	}
4100	+
4101	+	/**
4102	+	* Returns a non-null result from applying the given search
4103	+	* function on each entry, or null if none.  Upon success,
4104	+	* further element processing is suppressed and the results of
4105	+	* any other parallel invocations of the search function are
4106	+	* ignored.
4107	+	*
4108	+	* @param parallelismThreshold the (estimated) number of elements
4109	+	* needed for this operation to be executed in parallel
4110	+	* @param searchFunction a function returning a non-null
4111	+	* result on success, else null
4112	+	* @return a non-null result from applying the given search
4113	+	* function on each entry, or null if none
4114	+	* @since 1.8
4115	+	*/
4116	+	public <U> U searchEntries(long parallelismThreshold,
4117	+	Fun<Map.Entry<K,V>, ? extends U> searchFunction) {
4118	+	if (searchFunction == null) throw new NullPointerException();
4119	+	return new SearchEntriesTask<K,V,U>
4120	+	(null, batchFor(parallelismThreshold), 0, 0, table,
4121	+	searchFunction, new AtomicReference<U>()).invoke();
4122	+	}
4123	+
4124	+	/**
4125	+	* Returns the result of accumulating all entries using the
4126	+	* given reducer to combine values, or null if none.
4127	+	*
4128	+	* @param parallelismThreshold the (estimated) number of elements
4129	+	* needed for this operation to be executed in parallel
4130	+	* @param reducer a commutative associative combining function
4131	+	* @return the result of accumulating all entries
4132	+	* @since 1.8
4133	+	*/
4134	+	public Map.Entry<K,V> reduceEntries(long parallelismThreshold,
4135	+	BiFun<Map.Entry<K,V>, Map.Entry<K,V>, ? extends Map.Entry<K,V>> reducer) {
4136	+	if (reducer == null) throw new NullPointerException();
4137	+	return new ReduceEntriesTask<K,V>
4138	+	(null, batchFor(parallelismThreshold), 0, 0, table,
4139	+	null, reducer).invoke();
4140	+	}
4141	+
4142	+	/**
4143	+	* Returns the result of accumulating the given transformation
4144	+	* of all entries using the given reducer to combine values,
4145	+	* or null if none.
4146	+	*
4147	+	* @param parallelismThreshold the (estimated) number of elements
4148	+	* needed for this operation to be executed in parallel
4149	+	* @param transformer a function returning the transformation
4150	+	* for an element, or null if there is no transformation (in
4151	+	* which case it is not combined)
4152	+	* @param reducer a commutative associative combining function
4153	+	* @return the result of accumulating the given transformation
4154	+	* of all entries
4155	+	* @since 1.8
4156	+	*/
4157	+	public <U> U reduceEntries(long parallelismThreshold,
4158	+	Fun<Map.Entry<K,V>, ? extends U> transformer,
4159	+	BiFun<? super U, ? super U, ? extends U> reducer) {
4160	+	if (transformer == null || reducer == null)
4161	+	throw new NullPointerException();
4162	+	return new MapReduceEntriesTask<K,V,U>
4163	+	(null, batchFor(parallelismThreshold), 0, 0, table,
4164	+	null, transformer, reducer).invoke();
4165	+	}
4166	+
4167	+	/**
4168	+	* Returns the result of accumulating the given transformation
4169	+	* of all entries using the given reducer to combine values,
4170	+	* and the given basis as an identity value.
4171	+	*
4172	+	* @param parallelismThreshold the (estimated) number of elements
4173	+	* needed for this operation to be executed in parallel
4174	+	* @param transformer a function returning the transformation
4175	+	* for an element
4176	+	* @param basis the identity (initial default value) for the reduction
4177	+	* @param reducer a commutative associative combining function
4178	+	* @return the result of accumulating the given transformation
4179	+	* of all entries
4180	+	* @since 1.8
4181	+	*/
4182	+	public double reduceEntriesToDouble(long parallelismThreshold,
4183	+	ObjectToDouble<Map.Entry<K,V>> transformer,
4184	+	double basis,
4185	+	DoubleByDoubleToDouble reducer) {
4186	+	if (transformer == null || reducer == null)
4187	+	throw new NullPointerException();
4188	+	return new MapReduceEntriesToDoubleTask<K,V>
4189	+	(null, batchFor(parallelismThreshold), 0, 0, table,
4190	+	null, transformer, basis, reducer).invoke();
4191	+	}
4192	+
4193	+	/**
4194	+	* Returns the result of accumulating the given transformation
4195	+	* of all entries using the given reducer to combine values,
4196	+	* and the given basis as an identity value.
4197	+	*
4198	+	* @param parallelismThreshold the (estimated) number of elements
4199	+	* needed for this operation to be executed in parallel
4200	+	* @param transformer a function returning the transformation
4201	+	* for an element
4202	+	* @param basis the identity (initial default value) for the reduction
4203	+	* @param reducer a commutative associative combining function
4204	+	* @return the result of accumulating the given transformation
4205	+	* of all entries
4206	+	* @since 1.8
4207	+	*/
4208	+	public long reduceEntriesToLong(long parallelismThreshold,
4209	+	ObjectToLong<Map.Entry<K,V>> transformer,
4210	+	long basis,
4211	+	LongByLongToLong reducer) {
4212	+	if (transformer == null || reducer == null)
4213	+	throw new NullPointerException();
4214	+	return new MapReduceEntriesToLongTask<K,V>
4215	+	(null, batchFor(parallelismThreshold), 0, 0, table,
4216	+	null, transformer, basis, reducer).invoke();
4217	+	}
4218	+
4219	+	/**
4220	+	* Returns the result of accumulating the given transformation
4221	+	* of all entries using the given reducer to combine values,
4222	+	* and the given basis as an identity value.
4223	+	*
4224	+	* @param parallelismThreshold the (estimated) number of elements
4225	+	* needed for this operation to be executed in parallel
4226	+	* @param transformer a function returning the transformation
4227	+	* for an element
4228	+	* @param basis the identity (initial default value) for the reduction
4229	+	* @param reducer a commutative associative combining function
4230	+	* @return the result of accumulating the given transformation
4231	+	* of all entries
4232	+	* @since 1.8
4233	+	*/
4234	+	public int reduceEntriesToInt(long parallelismThreshold,
4235	+	ObjectToInt<Map.Entry<K,V>> transformer,
4236	+	int basis,
4237	+	IntByIntToInt reducer) {
4238	+	if (transformer == null || reducer == null)
4239	+	throw new NullPointerException();
4240	+	return new MapReduceEntriesToIntTask<K,V>
4241	+	(null, batchFor(parallelismThreshold), 0, 0, table,
4242	+	null, transformer, basis, reducer).invoke();
4243	+	}
4244	+
4245	+
4246		/* ----------------Views -------------- */
4247
4248		/**
4249		* Base class for views.
4250		*/
4251	<	static abstract class MapView<K, V> {
4252	<	final ConcurrentHashMapV8<K, V> map;
4253	<	MapView(ConcurrentHashMapV8<K, V> map)  { this.map = map; }
4254	<	public final int size()                 { return map.size(); }
4255	<	public final boolean isEmpty()          { return map.isEmpty(); }
4256	<	public final void clear()               { map.clear(); }
4251	>	abstract static class CollectionView<K,V,E>
4252	>	implements Collection<E>, java.io.Serializable {
4253	>	private static final long serialVersionUID = 7249069246763182397L;
4254	>	final ConcurrentHashMapV8<K,V> map;
4255	>	CollectionView(ConcurrentHashMapV8<K,V> map)  { this.map = map; }
4256	>
4257	>	/**
4258	>	* Returns the map backing this view.
4259	>	*
4260	>	* @return the map backing this view
4261	>	*/
4262	>	public ConcurrentHashMapV8<K,V> getMap() { return map; }
4263	>
4264	>	/**
4265	>	* Removes all of the elements from this view, by removing all
4266	>	* the mappings from the map backing this view.
4267	>	*/
4268	>	public final void clear()      { map.clear(); }
4269	>	public final int size()        { return map.size(); }
4270	>	public final boolean isEmpty() { return map.isEmpty(); }
4271
4272		// implementations below rely on concrete classes supplying these
4273	<	abstract public Iterator<?> iterator();
4274	<	abstract public boolean contains(Object o);
4275	<	abstract public boolean remove(Object o);
4273	>	// abstract methods
4274	>	/**
4275	>	* Returns a "weakly consistent" iterator that will never
4276	>	* throw {@link ConcurrentModificationException}, and
4277	>	* guarantees to traverse elements as they existed upon
4278	>	* construction of the iterator, and may (but is not
4279	>	* guaranteed to) reflect any modifications subsequent to
4280	>	* construction.
4281	>	*/
4282	>	public abstract Iterator<E> iterator();
4283	>	public abstract boolean contains(Object o);
4284	>	public abstract boolean remove(Object o);
4285
4286		private static final String oomeMsg = "Required array size too large";
4287
4288		public final Object[] toArray() {
4289	<	long sz = map.longSize();
4290	<	if (sz > (long)(MAX_ARRAY_SIZE))
4289	>	long sz = map.mappingCount();
4290	>	if (sz > MAX_ARRAY_SIZE)
4291		throw new OutOfMemoryError(oomeMsg);
4292		int n = (int)sz;
4293		Object[] r = new Object[n];
4294		int i = 0;
4295	<	Iterator<?> it = iterator();
2985	<	while (it.hasNext()) {
4295	>	for (E e : this) {
4296		if (i == n) {
4297		if (n >= MAX_ARRAY_SIZE)
4298		throw new OutOfMemoryError(oomeMsg);
#	Line 2992 | Line 4302 | public class ConcurrentHashMapV8<K, V>
4302		n += (n >>> 1) + 1;
4303		r = Arrays.copyOf(r, n);
4304		}
4305	<	r[i++] = it.next();
4305	>	r[i++] = e;
4306		}
4307		return (i == n) ? r : Arrays.copyOf(r, i);
4308		}
4309
4310		@SuppressWarnings("unchecked")
4311		public final <T> T[] toArray(T[] a) {
4312	<	long sz = map.longSize();
4313	<	if (sz > (long)(MAX_ARRAY_SIZE))
4312	>	long sz = map.mappingCount();
4313	>	if (sz > MAX_ARRAY_SIZE)
4314		throw new OutOfMemoryError(oomeMsg);
4315		int m = (int)sz;
4316		T[] r = (a.length >= m) ? a :
#	Line 3008 | Line 4318 | public class ConcurrentHashMapV8<K, V>
4318		.newInstance(a.getClass().getComponentType(), m);
4319		int n = r.length;
4320		int i = 0;
4321	<	Iterator<?> it = iterator();
3012	<	while (it.hasNext()) {
4321	>	for (E e : this) {
4322		if (i == n) {
4323		if (n >= MAX_ARRAY_SIZE)
4324		throw new OutOfMemoryError(oomeMsg);
#	Line 3019 | Line 4328 | public class ConcurrentHashMapV8<K, V>
4328		n += (n >>> 1) + 1;
4329		r = Arrays.copyOf(r, n);
4330		}
4331	<	r[i++] = (T)it.next();
4331	>	r[i++] = (T)e;
4332		}
4333		if (a == r && i < n) {
4334		r[i] = null; // null-terminate
#	Line 3028 | Line 4337 | public class ConcurrentHashMapV8<K, V>
4337		return (i == n) ? r : Arrays.copyOf(r, i);
4338		}
4339
4340	<	public final int hashCode() {
4341	<	int h = 0;
4342	<	for (Iterator<?> it = iterator(); it.hasNext();)
4343	<	h += it.next().hashCode();
4344	<	return h;
4345	<	}
4346	<
4340	>	/**
4341	>	* Returns a string representation of this collection.
4342	>	* The string representation consists of the string representations
4343	>	* of the collection's elements in the order they are returned by
4344	>	* its iterator, enclosed in square brackets ({@code "[]"}).
4345	>	* Adjacent elements are separated by the characters {@code ", "}
4346	>	* (comma and space).  Elements are converted to strings as by
4347	>	* {@link String#valueOf(Object)}.
4348	>	*
4349	>	* @return a string representation of this collection
4350	>	*/
4351		public final String toString() {
4352		StringBuilder sb = new StringBuilder();
4353		sb.append('[');
4354	<	Iterator<?> it = iterator();
4354	>	Iterator<E> it = iterator();
4355		if (it.hasNext()) {
4356		for (;;) {
4357		Object e = it.next();
#	Line 3053 | Line 4366 | public class ConcurrentHashMapV8<K, V>
4366
4367		public final boolean containsAll(Collection<?> c) {
4368		if (c != this) {
4369	<	for (Iterator<?> it = c.iterator(); it.hasNext();) {
3057	<	Object e = it.next();
4369	>	for (Object e : c) {
4370		if (e == null || !contains(e))
4371		return false;
4372		}
#	Line 3064 | Line 4376 | public class ConcurrentHashMapV8<K, V>
4376
4377		public final boolean removeAll(Collection<?> c) {
4378		boolean modified = false;
4379	<	for (Iterator<?> it = iterator(); it.hasNext();) {
4379	>	for (Iterator<E> it = iterator(); it.hasNext();) {
4380		if (c.contains(it.next())) {
4381		it.remove();
4382		modified = true;
#	Line 3075 | Line 4387 | public class ConcurrentHashMapV8<K, V>
4387
4388		public final boolean retainAll(Collection<?> c) {
4389		boolean modified = false;
4390	<	for (Iterator<?> it = iterator(); it.hasNext();) {
4390	>	for (Iterator<E> it = iterator(); it.hasNext();) {
4391		if (!c.contains(it.next())) {
4392		it.remove();
4393		modified = true;
#	Line 3086 | Line 4398 | public class ConcurrentHashMapV8<K, V>
4398
4399		}
4400
4401	<	static final class KeySet<K,V> extends MapView<K,V> implements Set<K> {
4402	<	KeySet(ConcurrentHashMapV8<K, V> map)   { super(map); }
4403	<	public final boolean contains(Object o) { return map.containsKey(o); }
4404	<	public final boolean remove(Object o)   { return map.remove(o) != null; }
4405	<	public final Iterator<K> iterator() {
4406	<	return new KeyIterator<K,V>(map);
4401	>	/**
4402	>	* A view of a ConcurrentHashMapV8 as a {@link Set} of keys, in
4403	>	* which additions may optionally be enabled by mapping to a
4404	>	* common value.  This class cannot be directly instantiated.
4405	>	* See {@link #keySet() keySet()},
4406	>	* {@link #keySet(Object) keySet(V)},
4407	>	* {@link #newKeySet() newKeySet()},
4408	>	* {@link #newKeySet(int) newKeySet(int)}.
4409	>	*
4410	>	* @since 1.8
4411	>	*/
4412	>	public static class KeySetView<K,V> extends CollectionView<K,V,K>
4413	>	implements Set<K>, java.io.Serializable {
4414	>	private static final long serialVersionUID = 7249069246763182397L;
4415	>	private final V value;
4416	>	KeySetView(ConcurrentHashMapV8<K,V> map, V value) {  // non-public
4417	>	super(map);
4418	>	this.value = value;
4419		}
4420	<	public final boolean add(K e) {
4421	<	throw new UnsupportedOperationException();
4420	>
4421	>	/**
4422	>	* Returns the default mapped value for additions,
4423	>	* or {@code null} if additions are not supported.
4424	>	*
4425	>	* @return the default mapped value for additions, or {@code null}
4426	>	* if not supported
4427	>	*/
4428	>	public V getMappedValue() { return value; }
4429	>
4430	>	/**
4431	>	* {@inheritDoc}
4432	>	* @throws NullPointerException if the specified key is null
4433	>	*/
4434	>	public boolean contains(Object o) { return map.containsKey(o); }
4435	>
4436	>	/**
4437	>	* Removes the key from this map view, by removing the key (and its
4438	>	* corresponding value) from the backing map.  This method does
4439	>	* nothing if the key is not in the map.
4440	>	*
4441	>	* @param  o the key to be removed from the backing map
4442	>	* @return {@code true} if the backing map contained the specified key
4443	>	* @throws NullPointerException if the specified key is null
4444	>	*/
4445	>	public boolean remove(Object o) { return map.remove(o) != null; }
4446	>
4447	>	/**
4448	>	* @return an iterator over the keys of the backing map
4449	>	*/
4450	>	public Iterator<K> iterator() {
4451	>	Node<K,V>[] t;
4452	>	ConcurrentHashMapV8<K,V> m = map;
4453	>	int f = (t = m.table) == null ? 0 : t.length;
4454	>	return new KeyIterator<K,V>(t, f, 0, f, m);
4455		}
4456	<	public final boolean addAll(Collection<? extends K> c) {
4457	<	throw new UnsupportedOperationException();
4456	>
4457	>	/**
4458	>	* Adds the specified key to this set view by mapping the key to
4459	>	* the default mapped value in the backing map, if defined.
4460	>	*
4461	>	* @param e key to be added
4462	>	* @return {@code true} if this set changed as a result of the call
4463	>	* @throws NullPointerException if the specified key is null
4464	>	* @throws UnsupportedOperationException if no default mapped value
4465	>	* for additions was provided
4466	>	*/
4467	>	public boolean add(K e) {
4468	>	V v;
4469	>	if ((v = value) == null)
4470	>	throw new UnsupportedOperationException();
4471	>	return map.putVal(e, v, true) == null;
4472	>	}
4473	>
4474	>	/**
4475	>	* Adds all of the elements in the specified collection to this set,
4476	>	* as if by calling {@link #add} on each one.
4477	>	*
4478	>	* @param c the elements to be inserted into this set
4479	>	* @return {@code true} if this set changed as a result of the call
4480	>	* @throws NullPointerException if the collection or any of its
4481	>	* elements are {@code null}
4482	>	* @throws UnsupportedOperationException if no default mapped value
4483	>	* for additions was provided
4484	>	*/
4485	>	public boolean addAll(Collection<? extends K> c) {
4486	>	boolean added = false;
4487	>	V v;
4488	>	if ((v = value) == null)
4489	>	throw new UnsupportedOperationException();
4490	>	for (K e : c) {
4491	>	if (map.putVal(e, v, true) == null)
4492	>	added = true;
4493	>	}
4494	>	return added;
4495		}
4496	+
4497	+	public int hashCode() {
4498	+	int h = 0;
4499	+	for (K e : this)
4500	+	h += e.hashCode();
4501	+	return h;
4502	+	}
4503	+
4504		public boolean equals(Object o) {
4505		Set<?> c;
4506		return ((o instanceof Set) &&
4507		((c = (Set<?>)o) == this ||
4508		(containsAll(c) && c.containsAll(this))));
4509		}
4510	+
4511	+	public ConcurrentHashMapSpliterator<K> spliterator() {
4512	+	Node<K,V>[] t;
4513	+	ConcurrentHashMapV8<K,V> m = map;
4514	+	long n = m.sumCount();
4515	+	int f = (t = m.table) == null ? 0 : t.length;
4516	+	return new KeySpliterator<K,V>(t, f, 0, f, n < 0L ? 0L : n);
4517	+	}
4518	+
4519	+	public void forEach(Action<? super K> action) {
4520	+	if (action == null) throw new NullPointerException();
4521	+	Node<K,V>[] t;
4522	+	if ((t = map.table) != null) {
4523	+	Traverser<K,V> it = new Traverser<K,V>(t, t.length, 0, t.length);
4524	+	for (Node<K,V> p; (p = it.advance()) != null; )
4525	+	action.apply(p.key);
4526	+	}
4527	+	}
4528		}
4529
4530	<	static final class Values<K,V> extends MapView<K,V>
4531	<	implements Collection<V> {
4532	<	Values(ConcurrentHashMapV8<K, V> map)   { super(map); }
4533	<	public final boolean contains(Object o) { return map.containsValue(o); }
4530	>	/**
4531	>	* A view of a ConcurrentHashMapV8 as a {@link Collection} of
4532	>	* values, in which additions are disabled. This class cannot be
4533	>	* directly instantiated. See {@link #values()}.
4534	>	*/
4535	>	static final class ValuesView<K,V> extends CollectionView<K,V,V>
4536	>	implements Collection<V>, java.io.Serializable {
4537	>	private static final long serialVersionUID = 2249069246763182397L;
4538	>	ValuesView(ConcurrentHashMapV8<K,V> map) { super(map); }
4539	>	public final boolean contains(Object o) {
4540	>	return map.containsValue(o);
4541	>	}
4542	>
4543		public final boolean remove(Object o) {
4544		if (o != null) {
4545	<	Iterator<V> it = new ValueIterator<K,V>(map);
3117	<	while (it.hasNext()) {
4545	>	for (Iterator<V> it = iterator(); it.hasNext();) {
4546		if (o.equals(it.next())) {
4547		it.remove();
4548		return true;
#	Line 3123 | Line 4551 | public class ConcurrentHashMapV8<K, V>
4551		}
4552		return false;
4553		}
4554	+
4555		public final Iterator<V> iterator() {
4556	<	return new ValueIterator<K,V>(map);
4556	>	ConcurrentHashMapV8<K,V> m = map;
4557	>	Node<K,V>[] t;
4558	>	int f = (t = m.table) == null ? 0 : t.length;
4559	>	return new ValueIterator<K,V>(t, f, 0, f, m);
4560		}
4561	+
4562		public final boolean add(V e) {
4563		throw new UnsupportedOperationException();
4564		}
4565		public final boolean addAll(Collection<? extends V> c) {
4566		throw new UnsupportedOperationException();
4567		}
4568	+
4569	+	public ConcurrentHashMapSpliterator<V> spliterator() {
4570	+	Node<K,V>[] t;
4571	+	ConcurrentHashMapV8<K,V> m = map;
4572	+	long n = m.sumCount();
4573	+	int f = (t = m.table) == null ? 0 : t.length;
4574	+	return new ValueSpliterator<K,V>(t, f, 0, f, n < 0L ? 0L : n);
4575	+	}
4576	+
4577	+	public void forEach(Action<? super V> action) {
4578	+	if (action == null) throw new NullPointerException();
4579	+	Node<K,V>[] t;
4580	+	if ((t = map.table) != null) {
4581	+	Traverser<K,V> it = new Traverser<K,V>(t, t.length, 0, t.length);
4582	+	for (Node<K,V> p; (p = it.advance()) != null; )
4583	+	action.apply(p.val);
4584	+	}
4585	+	}
4586		}
4587
4588	<	static final class EntrySet<K,V> extends MapView<K,V>
4589	<	implements Set<Map.Entry<K,V>> {
4590	<	EntrySet(ConcurrentHashMapV8<K, V> map) { super(map); }
4591	<	public final boolean contains(Object o) {
4588	>	/**
4589	>	* A view of a ConcurrentHashMapV8 as a {@link Set} of (key, value)
4590	>	* entries.  This class cannot be directly instantiated. See
4591	>	* {@link #entrySet()}.
4592	>	*/
4593	>	static final class EntrySetView<K,V> extends CollectionView<K,V,Map.Entry<K,V>>
4594	>	implements Set<Map.Entry<K,V>>, java.io.Serializable {
4595	>	private static final long serialVersionUID = 2249069246763182397L;
4596	>	EntrySetView(ConcurrentHashMapV8<K,V> map) { super(map); }
4597	>
4598	>	public boolean contains(Object o) {
4599		Object k, v, r; Map.Entry<?,?> e;
4600		return ((o instanceof Map.Entry) &&
4601		(k = (e = (Map.Entry<?,?>)o).getKey()) != null &&
#	Line 3145 | Line 4603 | public class ConcurrentHashMapV8<K, V>
4603		(v = e.getValue()) != null &&
4604		(v == r || v.equals(r)));
4605		}
4606	<	public final boolean remove(Object o) {
4606	>
4607	>	public boolean remove(Object o) {
4608		Object k, v; Map.Entry<?,?> e;
4609		return ((o instanceof Map.Entry) &&
4610		(k = (e = (Map.Entry<?,?>)o).getKey()) != null &&
4611		(v = e.getValue()) != null &&
4612		map.remove(k, v));
4613		}
4614	<	public final Iterator<Map.Entry<K,V>> iterator() {
4615	<	return new EntryIterator<K,V>(map);
4614	>
4615	>	/**
4616	>	* @return an iterator over the entries of the backing map
4617	>	*/
4618	>	public Iterator<Map.Entry<K,V>> iterator() {
4619	>	ConcurrentHashMapV8<K,V> m = map;
4620	>	Node<K,V>[] t;
4621	>	int f = (t = m.table) == null ? 0 : t.length;
4622	>	return new EntryIterator<K,V>(t, f, 0, f, m);
4623		}
4624	<	public final boolean add(Entry<K,V> e) {
4625	<	throw new UnsupportedOperationException();
4624	>
4625	>	public boolean add(Entry<K,V> e) {
4626	>	return map.putVal(e.getKey(), e.getValue(), false) == null;
4627		}
4628	<	public final boolean addAll(Collection<? extends Entry<K,V>> c) {
4629	<	throw new UnsupportedOperationException();
4628	>
4629	>	public boolean addAll(Collection<? extends Entry<K,V>> c) {
4630	>	boolean added = false;
4631	>	for (Entry<K,V> e : c) {
4632	>	if (add(e))
4633	>	added = true;
4634	>	}
4635	>	return added;
4636		}
4637	<	public boolean equals(Object o) {
4637	>
4638	>	public final int hashCode() {
4639	>	int h = 0;
4640	>	Node<K,V>[] t;
4641	>	if ((t = map.table) != null) {
4642	>	Traverser<K,V> it = new Traverser<K,V>(t, t.length, 0, t.length);
4643	>	for (Node<K,V> p; (p = it.advance()) != null; ) {
4644	>	h += p.hashCode();
4645	>	}
4646	>	}
4647	>	return h;
4648	>	}
4649	>
4650	>	public final boolean equals(Object o) {
4651		Set<?> c;
4652		return ((o instanceof Set) &&
4653		((c = (Set<?>)o) == this ||
4654		(containsAll(c) && c.containsAll(this))));
4655		}
4656	+
4657	+	public ConcurrentHashMapSpliterator<Map.Entry<K,V>> spliterator() {
4658	+	Node<K,V>[] t;
4659	+	ConcurrentHashMapV8<K,V> m = map;
4660	+	long n = m.sumCount();
4661	+	int f = (t = m.table) == null ? 0 : t.length;
4662	+	return new EntrySpliterator<K,V>(t, f, 0, f, n < 0L ? 0L : n, m);
4663	+	}
4664	+
4665	+	public void forEach(Action<? super Map.Entry<K,V>> action) {
4666	+	if (action == null) throw new NullPointerException();
4667	+	Node<K,V>[] t;
4668	+	if ((t = map.table) != null) {
4669	+	Traverser<K,V> it = new Traverser<K,V>(t, t.length, 0, t.length);
4670	+	for (Node<K,V> p; (p = it.advance()) != null; )
4671	+	action.apply(new MapEntry<K,V>(p.key, p.val, map));
4672	+	}
4673	+	}
4674	+
4675		}
4676
4677	<	/* ---------------- Serialization Support -------------- */
4677	>	// -------------------------------------------------------
4678
4679		/**
4680	<	* Stripped-down version of helper class used in previous version,
4681	<	* declared for the sake of serialization compatibility
4680	>	* Base class for bulk tasks. Repeats some fields and code from
4681	>	* class Traverser, because we need to subclass CountedCompleter.
4682		*/
4683	<	static class Segment<K,V> implements Serializable {
4684	<	private static final long serialVersionUID = 2249069246763182397L;
4685	<	final float loadFactor;
4686	<	Segment(float lf) { this.loadFactor = lf; }
4683	>	abstract static class BulkTask<K,V,R> extends CountedCompleter<R> {
4684	>	Node<K,V>[] tab;        // same as Traverser
4685	>	Node<K,V> next;
4686	>	int index;
4687	>	int baseIndex;
4688	>	int baseLimit;
4689	>	final int baseSize;
4690	>	int batch;              // split control
4691	>
4692	>	BulkTask(BulkTask<K,V,?> par, int b, int i, int f, Node<K,V>[] t) {
4693	>	super(par);
4694	>	this.batch = b;
4695	>	this.index = this.baseIndex = i;
4696	>	if ((this.tab = t) == null)
4697	>	this.baseSize = this.baseLimit = 0;
4698	>	else if (par == null)
4699	>	this.baseSize = this.baseLimit = t.length;
4700	>	else {
4701	>	this.baseLimit = f;
4702	>	this.baseSize = par.baseSize;
4703	>	}
4704	>	}
4705	>
4706	>	/**
4707	>	* Same as Traverser version
4708	>	*/
4709	>	final Node<K,V> advance() {
4710	>	Node<K,V> e;
4711	>	if ((e = next) != null)
4712	>	e = e.next;
4713	>	for (;;) {
4714	>	Node<K,V>[] t; int i, n; K ek;  // must use locals in checks
4715	>	if (e != null)
4716	>	return next = e;
4717	>	if (baseIndex >= baseLimit || (t = tab) == null ||
4718	>	(n = t.length) <= (i = index) || i < 0)
4719	>	return next = null;
4720	>	if ((e = tabAt(t, index)) != null && e.hash < 0) {
4721	>	if (e instanceof ForwardingNode) {
4722	>	tab = ((ForwardingNode<K,V>)e).nextTable;
4723	>	e = null;
4724	>	continue;
4725	>	}
4726	>	else if (e instanceof TreeBin)
4727	>	e = ((TreeBin<K,V>)e).first;
4728	>	else
4729	>	e = null;
4730	>	}
4731	>	if ((index += baseSize) >= n)
4732	>	index = ++baseIndex;    // visit upper slots if present
4733	>	}
4734	>	}
4735		}
4736
4737	<	/**
4738	<	* Saves the state of the {@code ConcurrentHashMapV8} instance to a
4739	<	* stream (i.e., serializes it).
4740	<	* @param s the stream
4741	<	* @serialData
4742	<	* the key (Object) and value (Object)
4743	<	* for each key-value mapping, followed by a null pair.
4744	<	* The key-value mappings are emitted in no particular order.
4745	<	*/
4746	<	@SuppressWarnings("unchecked")
4747	<	private void writeObject(java.io.ObjectOutputStream s)
4748	<	throws java.io.IOException {
4749	<	if (segments == null) { // for serialization compatibility
4750	<	segments = (Segment<K,V>[])
4751	<	new Segment<?,?>[DEFAULT_CONCURRENCY_LEVEL];
4752	<	for (int i = 0; i < segments.length; ++i)
4753	<	segments[i] = new Segment<K,V>(LOAD_FACTOR);
4754	<	}
4755	<	s.defaultWriteObject();
4756	<	InternalIterator<K,V> it = new InternalIterator<K,V>(this);
4757	<	Object v;
4758	<	while ((v = it.advance()) != null) {
4759	<	s.writeObject(it.nextKey);
4760	<	s.writeObject(v);
4737	>	/*
4738	>	* Task classes. Coded in a regular but ugly format/style to
4739	>	* simplify checks that each variant differs in the right way from
4740	>	* others. The null screenings exist because compilers cannot tell
4741	>	* that we've already null-checked task arguments, so we force
4742	>	* simplest hoisted bypass to help avoid convoluted traps.
4743	>	*/
4744	>	@SuppressWarnings("serial")
4745	>	static final class ForEachKeyTask<K,V>
4746	>	extends BulkTask<K,V,Void> {
4747	>	final Action<? super K> action;
4748	>	ForEachKeyTask
4749	>	(BulkTask<K,V,?> p, int b, int i, int f, Node<K,V>[] t,
4750	>	Action<? super K> action) {
4751	>	super(p, b, i, f, t);
4752	>	this.action = action;
4753	>	}
4754	>	public final void compute() {
4755	>	final Action<? super K> action;
4756	>	if ((action = this.action) != null) {
4757	>	for (int i = baseIndex, f, h; batch > 0 &&
4758	>	(h = ((f = baseLimit) + i) >>> 1) > i;) {
4759	>	addToPendingCount(1);
4760	>	new ForEachKeyTask<K,V>
4761	>	(this, batch >>>= 1, baseLimit = h, f, tab,
4762	>	action).fork();
4763	>	}
4764	>	for (Node<K,V> p; (p = advance()) != null;)
4765	>	action.apply(p.key);
4766	>	propagateCompletion();
4767	>	}
4768	>	}
4769	>	}
4770	>
4771	>	@SuppressWarnings("serial")
4772	>	static final class ForEachValueTask<K,V>
4773	>	extends BulkTask<K,V,Void> {
4774	>	final Action<? super V> action;
4775	>	ForEachValueTask
4776	>	(BulkTask<K,V,?> p, int b, int i, int f, Node<K,V>[] t,
4777	>	Action<? super V> action) {
4778	>	super(p, b, i, f, t);
4779	>	this.action = action;
4780	>	}
4781	>	public final void compute() {
4782	>	final Action<? super V> action;
4783	>	if ((action = this.action) != null) {
4784	>	for (int i = baseIndex, f, h; batch > 0 &&
4785	>	(h = ((f = baseLimit) + i) >>> 1) > i;) {
4786	>	addToPendingCount(1);
4787	>	new ForEachValueTask<K,V>
4788	>	(this, batch >>>= 1, baseLimit = h, f, tab,
4789	>	action).fork();
4790	>	}
4791	>	for (Node<K,V> p; (p = advance()) != null;)
4792	>	action.apply(p.val);
4793	>	propagateCompletion();
4794	>	}
4795	>	}
4796	>	}
4797	>
4798	>	@SuppressWarnings("serial")
4799	>	static final class ForEachEntryTask<K,V>
4800	>	extends BulkTask<K,V,Void> {
4801	>	final Action<? super Entry<K,V>> action;
4802	>	ForEachEntryTask
4803	>	(BulkTask<K,V,?> p, int b, int i, int f, Node<K,V>[] t,
4804	>	Action<? super Entry<K,V>> action) {
4805	>	super(p, b, i, f, t);
4806	>	this.action = action;
4807	>	}
4808	>	public final void compute() {
4809	>	final Action<? super Entry<K,V>> action;
4810	>	if ((action = this.action) != null) {
4811	>	for (int i = baseIndex, f, h; batch > 0 &&
4812	>	(h = ((f = baseLimit) + i) >>> 1) > i;) {
4813	>	addToPendingCount(1);
4814	>	new ForEachEntryTask<K,V>
4815	>	(this, batch >>>= 1, baseLimit = h, f, tab,
4816	>	action).fork();
4817	>	}
4818	>	for (Node<K,V> p; (p = advance()) != null; )
4819	>	action.apply(p);
4820	>	propagateCompletion();
4821	>	}
4822	>	}
4823	>	}
4824	>
4825	>	@SuppressWarnings("serial")
4826	>	static final class ForEachMappingTask<K,V>
4827	>	extends BulkTask<K,V,Void> {
4828	>	final BiAction<? super K, ? super V> action;
4829	>	ForEachMappingTask
4830	>	(BulkTask<K,V,?> p, int b, int i, int f, Node<K,V>[] t,
4831	>	BiAction<? super K,? super V> action) {
4832	>	super(p, b, i, f, t);
4833	>	this.action = action;
4834	>	}
4835	>	public final void compute() {
4836	>	final BiAction<? super K, ? super V> action;
4837	>	if ((action = this.action) != null) {
4838	>	for (int i = baseIndex, f, h; batch > 0 &&
4839	>	(h = ((f = baseLimit) + i) >>> 1) > i;) {
4840	>	addToPendingCount(1);
4841	>	new ForEachMappingTask<K,V>
4842	>	(this, batch >>>= 1, baseLimit = h, f, tab,
4843	>	action).fork();
4844	>	}
4845	>	for (Node<K,V> p; (p = advance()) != null; )
4846	>	action.apply(p.key, p.val);
4847	>	propagateCompletion();
4848	>	}
4849	>	}
4850	>	}
4851	>
4852	>	@SuppressWarnings("serial")
4853	>	static final class ForEachTransformedKeyTask<K,V,U>
4854	>	extends BulkTask<K,V,Void> {
4855	>	final Fun<? super K, ? extends U> transformer;
4856	>	final Action<? super U> action;
4857	>	ForEachTransformedKeyTask
4858	>	(BulkTask<K,V,?> p, int b, int i, int f, Node<K,V>[] t,
4859	>	Fun<? super K, ? extends U> transformer, Action<? super U> action) {
4860	>	super(p, b, i, f, t);
4861	>	this.transformer = transformer; this.action = action;
4862	>	}
4863	>	public final void compute() {
4864	>	final Fun<? super K, ? extends U> transformer;
4865	>	final Action<? super U> action;
4866	>	if ((transformer = this.transformer) != null &&
4867	>	(action = this.action) != null) {
4868	>	for (int i = baseIndex, f, h; batch > 0 &&
4869	>	(h = ((f = baseLimit) + i) >>> 1) > i;) {
4870	>	addToPendingCount(1);
4871	>	new ForEachTransformedKeyTask<K,V,U>
4872	>	(this, batch >>>= 1, baseLimit = h, f, tab,
4873	>	transformer, action).fork();
4874	>	}
4875	>	for (Node<K,V> p; (p = advance()) != null; ) {
4876	>	U u;
4877	>	if ((u = transformer.apply(p.key)) != null)
4878	>	action.apply(u);
4879	>	}
4880	>	propagateCompletion();
4881	>	}
4882	>	}
4883	>	}
4884	>
4885	>	@SuppressWarnings("serial")
4886	>	static final class ForEachTransformedValueTask<K,V,U>
4887	>	extends BulkTask<K,V,Void> {
4888	>	final Fun<? super V, ? extends U> transformer;
4889	>	final Action<? super U> action;
4890	>	ForEachTransformedValueTask
4891	>	(BulkTask<K,V,?> p, int b, int i, int f, Node<K,V>[] t,
4892	>	Fun<? super V, ? extends U> transformer, Action<? super U> action) {
4893	>	super(p, b, i, f, t);
4894	>	this.transformer = transformer; this.action = action;
4895	>	}
4896	>	public final void compute() {
4897	>	final Fun<? super V, ? extends U> transformer;
4898	>	final Action<? super U> action;
4899	>	if ((transformer = this.transformer) != null &&
4900	>	(action = this.action) != null) {
4901	>	for (int i = baseIndex, f, h; batch > 0 &&
4902	>	(h = ((f = baseLimit) + i) >>> 1) > i;) {
4903	>	addToPendingCount(1);
4904	>	new ForEachTransformedValueTask<K,V,U>
4905	>	(this, batch >>>= 1, baseLimit = h, f, tab,
4906	>	transformer, action).fork();
4907	>	}
4908	>	for (Node<K,V> p; (p = advance()) != null; ) {
4909	>	U u;
4910	>	if ((u = transformer.apply(p.val)) != null)
4911	>	action.apply(u);
4912	>	}
4913	>	propagateCompletion();
4914	>	}
4915	>	}
4916	>	}
4917	>
4918	>	@SuppressWarnings("serial")
4919	>	static final class ForEachTransformedEntryTask<K,V,U>
4920	>	extends BulkTask<K,V,Void> {
4921	>	final Fun<Map.Entry<K,V>, ? extends U> transformer;
4922	>	final Action<? super U> action;
4923	>	ForEachTransformedEntryTask
4924	>	(BulkTask<K,V,?> p, int b, int i, int f, Node<K,V>[] t,
4925	>	Fun<Map.Entry<K,V>, ? extends U> transformer, Action<? super U> action) {
4926	>	super(p, b, i, f, t);
4927	>	this.transformer = transformer; this.action = action;
4928	>	}
4929	>	public final void compute() {
4930	>	final Fun<Map.Entry<K,V>, ? extends U> transformer;
4931	>	final Action<? super U> action;
4932	>	if ((transformer = this.transformer) != null &&
4933	>	(action = this.action) != null) {
4934	>	for (int i = baseIndex, f, h; batch > 0 &&
4935	>	(h = ((f = baseLimit) + i) >>> 1) > i;) {
4936	>	addToPendingCount(1);
4937	>	new ForEachTransformedEntryTask<K,V,U>
4938	>	(this, batch >>>= 1, baseLimit = h, f, tab,
4939	>	transformer, action).fork();
4940	>	}
4941	>	for (Node<K,V> p; (p = advance()) != null; ) {
4942	>	U u;
4943	>	if ((u = transformer.apply(p)) != null)
4944	>	action.apply(u);
4945	>	}
4946	>	propagateCompletion();
4947	>	}
4948	>	}
4949	>	}
4950	>
4951	>	@SuppressWarnings("serial")
4952	>	static final class ForEachTransformedMappingTask<K,V,U>
4953	>	extends BulkTask<K,V,Void> {
4954	>	final BiFun<? super K, ? super V, ? extends U> transformer;
4955	>	final Action<? super U> action;
4956	>	ForEachTransformedMappingTask
4957	>	(BulkTask<K,V,?> p, int b, int i, int f, Node<K,V>[] t,
4958	>	BiFun<? super K, ? super V, ? extends U> transformer,
4959	>	Action<? super U> action) {
4960	>	super(p, b, i, f, t);
4961	>	this.transformer = transformer; this.action = action;
4962	>	}
4963	>	public final void compute() {
4964	>	final BiFun<? super K, ? super V, ? extends U> transformer;
4965	>	final Action<? super U> action;
4966	>	if ((transformer = this.transformer) != null &&
4967	>	(action = this.action) != null) {
4968	>	for (int i = baseIndex, f, h; batch > 0 &&
4969	>	(h = ((f = baseLimit) + i) >>> 1) > i;) {
4970	>	addToPendingCount(1);
4971	>	new ForEachTransformedMappingTask<K,V,U>
4972	>	(this, batch >>>= 1, baseLimit = h, f, tab,
4973	>	transformer, action).fork();
4974	>	}
4975	>	for (Node<K,V> p; (p = advance()) != null; ) {
4976	>	U u;
4977	>	if ((u = transformer.apply(p.key, p.val)) != null)
4978	>	action.apply(u);
4979	>	}
4980	>	propagateCompletion();
4981	>	}
4982	>	}
4983	>	}
4984	>
4985	>	@SuppressWarnings("serial")
4986	>	static final class SearchKeysTask<K,V,U>
4987	>	extends BulkTask<K,V,U> {
4988	>	final Fun<? super K, ? extends U> searchFunction;
4989	>	final AtomicReference<U> result;
4990	>	SearchKeysTask
4991	>	(BulkTask<K,V,?> p, int b, int i, int f, Node<K,V>[] t,
4992	>	Fun<? super K, ? extends U> searchFunction,
4993	>	AtomicReference<U> result) {
4994	>	super(p, b, i, f, t);
4995	>	this.searchFunction = searchFunction; this.result = result;
4996	>	}
4997	>	public final U getRawResult() { return result.get(); }
4998	>	public final void compute() {
4999	>	final Fun<? super K, ? extends U> searchFunction;
5000	>	final AtomicReference<U> result;
5001	>	if ((searchFunction = this.searchFunction) != null &&
5002	>	(result = this.result) != null) {
5003	>	for (int i = baseIndex, f, h; batch > 0 &&
5004	>	(h = ((f = baseLimit) + i) >>> 1) > i;) {
5005	>	if (result.get() != null)
5006	>	return;
5007	>	addToPendingCount(1);
5008	>	new SearchKeysTask<K,V,U>
5009	>	(this, batch >>>= 1, baseLimit = h, f, tab,
5010	>	searchFunction, result).fork();
5011	>	}
5012	>	while (result.get() == null) {
5013	>	U u;
5014	>	Node<K,V> p;
5015	>	if ((p = advance()) == null) {
5016	>	propagateCompletion();
5017	>	break;
5018	>	}
5019	>	if ((u = searchFunction.apply(p.key)) != null) {
5020	>	if (result.compareAndSet(null, u))
5021	>	quietlyCompleteRoot();
5022	>	break;
5023	>	}
5024	>	}
5025	>	}
5026		}
3209	–	s.writeObject(null);
3210	–	s.writeObject(null);
3211	–	segments = null; // throw away
5027		}
5028
5029	<	/**
5030	<	* Reconstitutes the instance from a stream (that is, deserializes it).
5031	<	* @param s the stream
5032	<	*/
5033	<	@SuppressWarnings("unchecked")
5034	<	private void readObject(java.io.ObjectInputStream s)
5035	<	throws java.io.IOException, ClassNotFoundException {
5036	<	s.defaultReadObject();
5037	<	this.segments = null; // unneeded
5038	<	// initialize transient final field
5039	<	UNSAFE.putObjectVolatile(this, counterOffset, new LongAdder());
5029	>	@SuppressWarnings("serial")
5030	>	static final class SearchValuesTask<K,V,U>
5031	>	extends BulkTask<K,V,U> {
5032	>	final Fun<? super V, ? extends U> searchFunction;
5033	>	final AtomicReference<U> result;
5034	>	SearchValuesTask
5035	>	(BulkTask<K,V,?> p, int b, int i, int f, Node<K,V>[] t,
5036	>	Fun<? super V, ? extends U> searchFunction,
5037	>	AtomicReference<U> result) {
5038	>	super(p, b, i, f, t);
5039	>	this.searchFunction = searchFunction; this.result = result;
5040	>	}
5041	>	public final U getRawResult() { return result.get(); }
5042	>	public final void compute() {
5043	>	final Fun<? super V, ? extends U> searchFunction;
5044	>	final AtomicReference<U> result;
5045	>	if ((searchFunction = this.searchFunction) != null &&
5046	>	(result = this.result) != null) {
5047	>	for (int i = baseIndex, f, h; batch > 0 &&
5048	>	(h = ((f = baseLimit) + i) >>> 1) > i;) {
5049	>	if (result.get() != null)
5050	>	return;
5051	>	addToPendingCount(1);
5052	>	new SearchValuesTask<K,V,U>
5053	>	(this, batch >>>= 1, baseLimit = h, f, tab,
5054	>	searchFunction, result).fork();
5055	>	}
5056	>	while (result.get() == null) {
5057	>	U u;
5058	>	Node<K,V> p;
5059	>	if ((p = advance()) == null) {
5060	>	propagateCompletion();
5061	>	break;
5062	>	}
5063	>	if ((u = searchFunction.apply(p.val)) != null) {
5064	>	if (result.compareAndSet(null, u))
5065	>	quietlyCompleteRoot();
5066	>	break;
5067	>	}
5068	>	}
5069	>	}
5070	>	}
5071	>	}
5072
5073	<	// Create all nodes, then place in table once size is known
5074	<	long size = 0L;
5075	<	Node p = null;
5076	<	for (;;) {
5077	<	K k = (K) s.readObject();
5078	<	V v = (V) s.readObject();
5079	<	if (k != null && v != null) {
5080	<	int h = spread(k.hashCode());
5081	<	p = new Node(h, k, v, p);
5082	<	++size;
5073	>	@SuppressWarnings("serial")
5074	>	static final class SearchEntriesTask<K,V,U>
5075	>	extends BulkTask<K,V,U> {
5076	>	final Fun<Entry<K,V>, ? extends U> searchFunction;
5077	>	final AtomicReference<U> result;
5078	>	SearchEntriesTask
5079	>	(BulkTask<K,V,?> p, int b, int i, int f, Node<K,V>[] t,
5080	>	Fun<Entry<K,V>, ? extends U> searchFunction,
5081	>	AtomicReference<U> result) {
5082	>	super(p, b, i, f, t);
5083	>	this.searchFunction = searchFunction; this.result = result;
5084	>	}
5085	>	public final U getRawResult() { return result.get(); }
5086	>	public final void compute() {
5087	>	final Fun<Entry<K,V>, ? extends U> searchFunction;
5088	>	final AtomicReference<U> result;
5089	>	if ((searchFunction = this.searchFunction) != null &&
5090	>	(result = this.result) != null) {
5091	>	for (int i = baseIndex, f, h; batch > 0 &&
5092	>	(h = ((f = baseLimit) + i) >>> 1) > i;) {
5093	>	if (result.get() != null)
5094	>	return;
5095	>	addToPendingCount(1);
5096	>	new SearchEntriesTask<K,V,U>
5097	>	(this, batch >>>= 1, baseLimit = h, f, tab,
5098	>	searchFunction, result).fork();
5099	>	}
5100	>	while (result.get() == null) {
5101	>	U u;
5102	>	Node<K,V> p;
5103	>	if ((p = advance()) == null) {
5104	>	propagateCompletion();
5105	>	break;
5106	>	}
5107	>	if ((u = searchFunction.apply(p)) != null) {
5108	>	if (result.compareAndSet(null, u))
5109	>	quietlyCompleteRoot();
5110	>	return;
5111	>	}
5112	>	}
5113		}
3237	–	else
3238	–	break;
5114		}
5115	<	if (p != null) {
5116	<	boolean init = false;
5117	<	int n;
5118	<	if (size >= (long)(MAXIMUM_CAPACITY >>> 1))
5119	<	n = MAXIMUM_CAPACITY;
5120	<	else {
5121	<	int sz = (int)size;
5122	<	n = tableSizeFor(sz + (sz >>> 1) + 1);
5115	>	}
5116	>
5117	>	@SuppressWarnings("serial")
5118	>	static final class SearchMappingsTask<K,V,U>
5119	>	extends BulkTask<K,V,U> {
5120	>	final BiFun<? super K, ? super V, ? extends U> searchFunction;
5121	>	final AtomicReference<U> result;
5122	>	SearchMappingsTask
5123	>	(BulkTask<K,V,?> p, int b, int i, int f, Node<K,V>[] t,
5124	>	BiFun<? super K, ? super V, ? extends U> searchFunction,
5125	>	AtomicReference<U> result) {
5126	>	super(p, b, i, f, t);
5127	>	this.searchFunction = searchFunction; this.result = result;
5128	>	}
5129	>	public final U getRawResult() { return result.get(); }
5130	>	public final void compute() {
5131	>	final BiFun<? super K, ? super V, ? extends U> searchFunction;
5132	>	final AtomicReference<U> result;
5133	>	if ((searchFunction = this.searchFunction) != null &&
5134	>	(result = this.result) != null) {
5135	>	for (int i = baseIndex, f, h; batch > 0 &&
5136	>	(h = ((f = baseLimit) + i) >>> 1) > i;) {
5137	>	if (result.get() != null)
5138	>	return;
5139	>	addToPendingCount(1);
5140	>	new SearchMappingsTask<K,V,U>
5141	>	(this, batch >>>= 1, baseLimit = h, f, tab,
5142	>	searchFunction, result).fork();
5143	>	}
5144	>	while (result.get() == null) {
5145	>	U u;
5146	>	Node<K,V> p;
5147	>	if ((p = advance()) == null) {
5148	>	propagateCompletion();
5149	>	break;
5150	>	}
5151	>	if ((u = searchFunction.apply(p.key, p.val)) != null) {
5152	>	if (result.compareAndSet(null, u))
5153	>	quietlyCompleteRoot();
5154	>	break;
5155	>	}
5156	>	}
5157		}
5158	<	int sc = sizeCtl;
5159	<	boolean collide = false;
5160	<	if (n > sc &&
5161	<	UNSAFE.compareAndSwapInt(this, sizeCtlOffset, sc, -1)) {
5162	<	try {
5163	<	if (table == null) {
5164	<	init = true;
5165	<	Node[] tab = new Node[n];
5166	<	int mask = n - 1;
5167	<	while (p != null) {
5168	<	int j = p.hash & mask;
5169	<	Node next = p.next;
5170	<	Node q = p.next = tabAt(tab, j);
5171	<	setTabAt(tab, j, p);
5172	<	if (!collide && q != null && q.hash == p.hash)
5173	<	collide = true;
5174	<	p = next;
5158	>	}
5159	>	}
5160	>
5161	>	@SuppressWarnings("serial")
5162	>	static final class ReduceKeysTask<K,V>
5163	>	extends BulkTask<K,V,K> {
5164	>	final BiFun<? super K, ? super K, ? extends K> reducer;
5165	>	K result;
5166	>	ReduceKeysTask<K,V> rights, nextRight;
5167	>	ReduceKeysTask
5168	>	(BulkTask<K,V,?> p, int b, int i, int f, Node<K,V>[] t,
5169	>	ReduceKeysTask<K,V> nextRight,
5170	>	BiFun<? super K, ? super K, ? extends K> reducer) {
5171	>	super(p, b, i, f, t); this.nextRight = nextRight;
5172	>	this.reducer = reducer;
5173	>	}
5174	>	public final K getRawResult() { return result; }
5175	>	public final void compute() {
5176	>	final BiFun<? super K, ? super K, ? extends K> reducer;
5177	>	if ((reducer = this.reducer) != null) {
5178	>	for (int i = baseIndex, f, h; batch > 0 &&
5179	>	(h = ((f = baseLimit) + i) >>> 1) > i;) {
5180	>	addToPendingCount(1);
5181	>	(rights = new ReduceKeysTask<K,V>
5182	>	(this, batch >>>= 1, baseLimit = h, f, tab,
5183	>	rights, reducer)).fork();
5184	>	}
5185	>	K r = null;
5186	>	for (Node<K,V> p; (p = advance()) != null; ) {
5187	>	K u = p.key;
5188	>	r = (r == null) ? u : u == null ? r : reducer.apply(r, u);
5189	>	}
5190	>	result = r;
5191	>	CountedCompleter<?> c;
5192	>	for (c = firstComplete(); c != null; c = c.nextComplete()) {
5193	>	@SuppressWarnings("unchecked") ReduceKeysTask<K,V>
5194	>	t = (ReduceKeysTask<K,V>)c,
5195	>	s = t.rights;
5196	>	while (s != null) {
5197	>	K tr, sr;
5198	>	if ((sr = s.result) != null)
5199	>	t.result = (((tr = t.result) == null) ? sr :
5200	>	reducer.apply(tr, sr));
5201	>	s = t.rights = s.nextRight;
5202	>	}
5203	>	}
5204	>	}
5205	>	}
5206	>	}
5207	>
5208	>	@SuppressWarnings("serial")
5209	>	static final class ReduceValuesTask<K,V>
5210	>	extends BulkTask<K,V,V> {
5211	>	final BiFun<? super V, ? super V, ? extends V> reducer;
5212	>	V result;
5213	>	ReduceValuesTask<K,V> rights, nextRight;
5214	>	ReduceValuesTask
5215	>	(BulkTask<K,V,?> p, int b, int i, int f, Node<K,V>[] t,
5216	>	ReduceValuesTask<K,V> nextRight,
5217	>	BiFun<? super V, ? super V, ? extends V> reducer) {
5218	>	super(p, b, i, f, t); this.nextRight = nextRight;
5219	>	this.reducer = reducer;
5220	>	}
5221	>	public final V getRawResult() { return result; }
5222	>	public final void compute() {
5223	>	final BiFun<? super V, ? super V, ? extends V> reducer;
5224	>	if ((reducer = this.reducer) != null) {
5225	>	for (int i = baseIndex, f, h; batch > 0 &&
5226	>	(h = ((f = baseLimit) + i) >>> 1) > i;) {
5227	>	addToPendingCount(1);
5228	>	(rights = new ReduceValuesTask<K,V>
5229	>	(this, batch >>>= 1, baseLimit = h, f, tab,
5230	>	rights, reducer)).fork();
5231	>	}
5232	>	V r = null;
5233	>	for (Node<K,V> p; (p = advance()) != null; ) {
5234	>	V v = p.val;
5235	>	r = (r == null) ? v : reducer.apply(r, v);
5236	>	}
5237	>	result = r;
5238	>	CountedCompleter<?> c;
5239	>	for (c = firstComplete(); c != null; c = c.nextComplete()) {
5240	>	@SuppressWarnings("unchecked") ReduceValuesTask<K,V>
5241	>	t = (ReduceValuesTask<K,V>)c,
5242	>	s = t.rights;
5243	>	while (s != null) {
5244	>	V tr, sr;
5245	>	if ((sr = s.result) != null)
5246	>	t.result = (((tr = t.result) == null) ? sr :
5247	>	reducer.apply(tr, sr));
5248	>	s = t.rights = s.nextRight;
5249	>	}
5250	>	}
5251	>	}
5252	>	}
5253	>	}
5254	>
5255	>	@SuppressWarnings("serial")
5256	>	static final class ReduceEntriesTask<K,V>
5257	>	extends BulkTask<K,V,Map.Entry<K,V>> {
5258	>	final BiFun<Map.Entry<K,V>, Map.Entry<K,V>, ? extends Map.Entry<K,V>> reducer;
5259	>	Map.Entry<K,V> result;
5260	>	ReduceEntriesTask<K,V> rights, nextRight;
5261	>	ReduceEntriesTask
5262	>	(BulkTask<K,V,?> p, int b, int i, int f, Node<K,V>[] t,
5263	>	ReduceEntriesTask<K,V> nextRight,
5264	>	BiFun<Entry<K,V>, Map.Entry<K,V>, ? extends Map.Entry<K,V>> reducer) {
5265	>	super(p, b, i, f, t); this.nextRight = nextRight;
5266	>	this.reducer = reducer;
5267	>	}
5268	>	public final Map.Entry<K,V> getRawResult() { return result; }
5269	>	public final void compute() {
5270	>	final BiFun<Map.Entry<K,V>, Map.Entry<K,V>, ? extends Map.Entry<K,V>> reducer;
5271	>	if ((reducer = this.reducer) != null) {
5272	>	for (int i = baseIndex, f, h; batch > 0 &&
5273	>	(h = ((f = baseLimit) + i) >>> 1) > i;) {
5274	>	addToPendingCount(1);
5275	>	(rights = new ReduceEntriesTask<K,V>
5276	>	(this, batch >>>= 1, baseLimit = h, f, tab,
5277	>	rights, reducer)).fork();
5278	>	}
5279	>	Map.Entry<K,V> r = null;
5280	>	for (Node<K,V> p; (p = advance()) != null; )
5281	>	r = (r == null) ? p : reducer.apply(r, p);
5282	>	result = r;
5283	>	CountedCompleter<?> c;
5284	>	for (c = firstComplete(); c != null; c = c.nextComplete()) {
5285	>	@SuppressWarnings("unchecked") ReduceEntriesTask<K,V>
5286	>	t = (ReduceEntriesTask<K,V>)c,
5287	>	s = t.rights;
5288	>	while (s != null) {
5289	>	Map.Entry<K,V> tr, sr;
5290	>	if ((sr = s.result) != null)
5291	>	t.result = (((tr = t.result) == null) ? sr :
5292	>	reducer.apply(tr, sr));
5293	>	s = t.rights = s.nextRight;
5294	>	}
5295	>	}
5296	>	}
5297	>	}
5298	>	}
5299	>
5300	>	@SuppressWarnings("serial")
5301	>	static final class MapReduceKeysTask<K,V,U>
5302	>	extends BulkTask<K,V,U> {
5303	>	final Fun<? super K, ? extends U> transformer;
5304	>	final BiFun<? super U, ? super U, ? extends U> reducer;
5305	>	U result;
5306	>	MapReduceKeysTask<K,V,U> rights, nextRight;
5307	>	MapReduceKeysTask
5308	>	(BulkTask<K,V,?> p, int b, int i, int f, Node<K,V>[] t,
5309	>	MapReduceKeysTask<K,V,U> nextRight,
5310	>	Fun<? super K, ? extends U> transformer,
5311	>	BiFun<? super U, ? super U, ? extends U> reducer) {
5312	>	super(p, b, i, f, t); this.nextRight = nextRight;
5313	>	this.transformer = transformer;
5314	>	this.reducer = reducer;
5315	>	}
5316	>	public final U getRawResult() { return result; }
5317	>	public final void compute() {
5318	>	final Fun<? super K, ? extends U> transformer;
5319	>	final BiFun<? super U, ? super U, ? extends U> reducer;
5320	>	if ((transformer = this.transformer) != null &&
5321	>	(reducer = this.reducer) != null) {
5322	>	for (int i = baseIndex, f, h; batch > 0 &&
5323	>	(h = ((f = baseLimit) + i) >>> 1) > i;) {
5324	>	addToPendingCount(1);
5325	>	(rights = new MapReduceKeysTask<K,V,U>
5326	>	(this, batch >>>= 1, baseLimit = h, f, tab,
5327	>	rights, transformer, reducer)).fork();
5328	>	}
5329	>	U r = null;
5330	>	for (Node<K,V> p; (p = advance()) != null; ) {
5331	>	U u;
5332	>	if ((u = transformer.apply(p.key)) != null)
5333	>	r = (r == null) ? u : reducer.apply(r, u);
5334	>	}
5335	>	result = r;
5336	>	CountedCompleter<?> c;
5337	>	for (c = firstComplete(); c != null; c = c.nextComplete()) {
5338	>	@SuppressWarnings("unchecked") MapReduceKeysTask<K,V,U>
5339	>	t = (MapReduceKeysTask<K,V,U>)c,
5340	>	s = t.rights;
5341	>	while (s != null) {
5342	>	U tr, sr;
5343	>	if ((sr = s.result) != null)
5344	>	t.result = (((tr = t.result) == null) ? sr :
5345	>	reducer.apply(tr, sr));
5346	>	s = t.rights = s.nextRight;
5347	>	}
5348	>	}
5349	>	}
5350	>	}
5351	>	}
5352	>
5353	>	@SuppressWarnings("serial")
5354	>	static final class MapReduceValuesTask<K,V,U>
5355	>	extends BulkTask<K,V,U> {
5356	>	final Fun<? super V, ? extends U> transformer;
5357	>	final BiFun<? super U, ? super U, ? extends U> reducer;
5358	>	U result;
5359	>	MapReduceValuesTask<K,V,U> rights, nextRight;
5360	>	MapReduceValuesTask
5361	>	(BulkTask<K,V,?> p, int b, int i, int f, Node<K,V>[] t,
5362	>	MapReduceValuesTask<K,V,U> nextRight,
5363	>	Fun<? super V, ? extends U> transformer,
5364	>	BiFun<? super U, ? super U, ? extends U> reducer) {
5365	>	super(p, b, i, f, t); this.nextRight = nextRight;
5366	>	this.transformer = transformer;
5367	>	this.reducer = reducer;
5368	>	}
5369	>	public final U getRawResult() { return result; }
5370	>	public final void compute() {
5371	>	final Fun<? super V, ? extends U> transformer;
5372	>	final BiFun<? super U, ? super U, ? extends U> reducer;
5373	>	if ((transformer = this.transformer) != null &&
5374	>	(reducer = this.reducer) != null) {
5375	>	for (int i = baseIndex, f, h; batch > 0 &&
5376	>	(h = ((f = baseLimit) + i) >>> 1) > i;) {
5377	>	addToPendingCount(1);
5378	>	(rights = new MapReduceValuesTask<K,V,U>
5379	>	(this, batch >>>= 1, baseLimit = h, f, tab,
5380	>	rights, transformer, reducer)).fork();
5381	>	}
5382	>	U r = null;
5383	>	for (Node<K,V> p; (p = advance()) != null; ) {
5384	>	U u;
5385	>	if ((u = transformer.apply(p.val)) != null)
5386	>	r = (r == null) ? u : reducer.apply(r, u);
5387	>	}
5388	>	result = r;
5389	>	CountedCompleter<?> c;
5390	>	for (c = firstComplete(); c != null; c = c.nextComplete()) {
5391	>	@SuppressWarnings("unchecked") MapReduceValuesTask<K,V,U>
5392	>	t = (MapReduceValuesTask<K,V,U>)c,
5393	>	s = t.rights;
5394	>	while (s != null) {
5395	>	U tr, sr;
5396	>	if ((sr = s.result) != null)
5397	>	t.result = (((tr = t.result) == null) ? sr :
5398	>	reducer.apply(tr, sr));
5399	>	s = t.rights = s.nextRight;
5400	>	}
5401	>	}
5402	>	}
5403	>	}
5404	>	}
5405	>
5406	>	@SuppressWarnings("serial")
5407	>	static final class MapReduceEntriesTask<K,V,U>
5408	>	extends BulkTask<K,V,U> {
5409	>	final Fun<Map.Entry<K,V>, ? extends U> transformer;
5410	>	final BiFun<? super U, ? super U, ? extends U> reducer;
5411	>	U result;
5412	>	MapReduceEntriesTask<K,V,U> rights, nextRight;
5413	>	MapReduceEntriesTask
5414	>	(BulkTask<K,V,?> p, int b, int i, int f, Node<K,V>[] t,
5415	>	MapReduceEntriesTask<K,V,U> nextRight,
5416	>	Fun<Map.Entry<K,V>, ? extends U> transformer,
5417	>	BiFun<? super U, ? super U, ? extends U> reducer) {
5418	>	super(p, b, i, f, t); this.nextRight = nextRight;
5419	>	this.transformer = transformer;
5420	>	this.reducer = reducer;
5421	>	}
5422	>	public final U getRawResult() { return result; }
5423	>	public final void compute() {
5424	>	final Fun<Map.Entry<K,V>, ? extends U> transformer;
5425	>	final BiFun<? super U, ? super U, ? extends U> reducer;
5426	>	if ((transformer = this.transformer) != null &&
5427	>	(reducer = this.reducer) != null) {
5428	>	for (int i = baseIndex, f, h; batch > 0 &&
5429	>	(h = ((f = baseLimit) + i) >>> 1) > i;) {
5430	>	addToPendingCount(1);
5431	>	(rights = new MapReduceEntriesTask<K,V,U>
5432	>	(this, batch >>>= 1, baseLimit = h, f, tab,
5433	>	rights, transformer, reducer)).fork();
5434	>	}
5435	>	U r = null;
5436	>	for (Node<K,V> p; (p = advance()) != null; ) {
5437	>	U u;
5438	>	if ((u = transformer.apply(p)) != null)
5439	>	r = (r == null) ? u : reducer.apply(r, u);
5440	>	}
5441	>	result = r;
5442	>	CountedCompleter<?> c;
5443	>	for (c = firstComplete(); c != null; c = c.nextComplete()) {
5444	>	@SuppressWarnings("unchecked") MapReduceEntriesTask<K,V,U>
5445	>	t = (MapReduceEntriesTask<K,V,U>)c,
5446	>	s = t.rights;
5447	>	while (s != null) {
5448	>	U tr, sr;
5449	>	if ((sr = s.result) != null)
5450	>	t.result = (((tr = t.result) == null) ? sr :
5451	>	reducer.apply(tr, sr));
5452	>	s = t.rights = s.nextRight;
5453	>	}
5454	>	}
5455	>	}
5456	>	}
5457	>	}
5458	>
5459	>	@SuppressWarnings("serial")
5460	>	static final class MapReduceMappingsTask<K,V,U>
5461	>	extends BulkTask<K,V,U> {
5462	>	final BiFun<? super K, ? super V, ? extends U> transformer;
5463	>	final BiFun<? super U, ? super U, ? extends U> reducer;
5464	>	U result;
5465	>	MapReduceMappingsTask<K,V,U> rights, nextRight;
5466	>	MapReduceMappingsTask
5467	>	(BulkTask<K,V,?> p, int b, int i, int f, Node<K,V>[] t,
5468	>	MapReduceMappingsTask<K,V,U> nextRight,
5469	>	BiFun<? super K, ? super V, ? extends U> transformer,
5470	>	BiFun<? super U, ? super U, ? extends U> reducer) {
5471	>	super(p, b, i, f, t); this.nextRight = nextRight;
5472	>	this.transformer = transformer;
5473	>	this.reducer = reducer;
5474	>	}
5475	>	public final U getRawResult() { return result; }
5476	>	public final void compute() {
5477	>	final BiFun<? super K, ? super V, ? extends U> transformer;
5478	>	final BiFun<? super U, ? super U, ? extends U> reducer;
5479	>	if ((transformer = this.transformer) != null &&
5480	>	(reducer = this.reducer) != null) {
5481	>	for (int i = baseIndex, f, h; batch > 0 &&
5482	>	(h = ((f = baseLimit) + i) >>> 1) > i;) {
5483	>	addToPendingCount(1);
5484	>	(rights = new MapReduceMappingsTask<K,V,U>
5485	>	(this, batch >>>= 1, baseLimit = h, f, tab,
5486	>	rights, transformer, reducer)).fork();
5487	>	}
5488	>	U r = null;
5489	>	for (Node<K,V> p; (p = advance()) != null; ) {
5490	>	U u;
5491	>	if ((u = transformer.apply(p.key, p.val)) != null)
5492	>	r = (r == null) ? u : reducer.apply(r, u);
5493	>	}
5494	>	result = r;
5495	>	CountedCompleter<?> c;
5496	>	for (c = firstComplete(); c != null; c = c.nextComplete()) {
5497	>	@SuppressWarnings("unchecked") MapReduceMappingsTask<K,V,U>
5498	>	t = (MapReduceMappingsTask<K,V,U>)c,
5499	>	s = t.rights;
5500	>	while (s != null) {
5501	>	U tr, sr;
5502	>	if ((sr = s.result) != null)
5503	>	t.result = (((tr = t.result) == null) ? sr :
5504	>	reducer.apply(tr, sr));
5505	>	s = t.rights = s.nextRight;
5506	>	}
5507	>	}
5508	>	}
5509	>	}
5510	>	}
5511	>
5512	>	@SuppressWarnings("serial")
5513	>	static final class MapReduceKeysToDoubleTask<K,V>
5514	>	extends BulkTask<K,V,Double> {
5515	>	final ObjectToDouble<? super K> transformer;
5516	>	final DoubleByDoubleToDouble reducer;
5517	>	final double basis;
5518	>	double result;
5519	>	MapReduceKeysToDoubleTask<K,V> rights, nextRight;
5520	>	MapReduceKeysToDoubleTask
5521	>	(BulkTask<K,V,?> p, int b, int i, int f, Node<K,V>[] t,
5522	>	MapReduceKeysToDoubleTask<K,V> nextRight,
5523	>	ObjectToDouble<? super K> transformer,
5524	>	double basis,
5525	>	DoubleByDoubleToDouble reducer) {
5526	>	super(p, b, i, f, t); this.nextRight = nextRight;
5527	>	this.transformer = transformer;
5528	>	this.basis = basis; this.reducer = reducer;
5529	>	}
5530	>	public final Double getRawResult() { return result; }
5531	>	public final void compute() {
5532	>	final ObjectToDouble<? super K> transformer;
5533	>	final DoubleByDoubleToDouble reducer;
5534	>	if ((transformer = this.transformer) != null &&
5535	>	(reducer = this.reducer) != null) {
5536	>	double r = this.basis;
5537	>	for (int i = baseIndex, f, h; batch > 0 &&
5538	>	(h = ((f = baseLimit) + i) >>> 1) > i;) {
5539	>	addToPendingCount(1);
5540	>	(rights = new MapReduceKeysToDoubleTask<K,V>
5541	>	(this, batch >>>= 1, baseLimit = h, f, tab,
5542	>	rights, transformer, r, reducer)).fork();
5543	>	}
5544	>	for (Node<K,V> p; (p = advance()) != null; )
5545	>	r = reducer.apply(r, transformer.apply(p.key));
5546	>	result = r;
5547	>	CountedCompleter<?> c;
5548	>	for (c = firstComplete(); c != null; c = c.nextComplete()) {
5549	>	@SuppressWarnings("unchecked") MapReduceKeysToDoubleTask<K,V>
5550	>	t = (MapReduceKeysToDoubleTask<K,V>)c,
5551	>	s = t.rights;
5552	>	while (s != null) {
5553	>	t.result = reducer.apply(t.result, s.result);
5554	>	s = t.rights = s.nextRight;
5555	>	}
5556	>	}
5557	>	}
5558	>	}
5559	>	}
5560	>
5561	>	@SuppressWarnings("serial")
5562	>	static final class MapReduceValuesToDoubleTask<K,V>
5563	>	extends BulkTask<K,V,Double> {
5564	>	final ObjectToDouble<? super V> transformer;
5565	>	final DoubleByDoubleToDouble reducer;
5566	>	final double basis;
5567	>	double result;
5568	>	MapReduceValuesToDoubleTask<K,V> rights, nextRight;
5569	>	MapReduceValuesToDoubleTask
5570	>	(BulkTask<K,V,?> p, int b, int i, int f, Node<K,V>[] t,
5571	>	MapReduceValuesToDoubleTask<K,V> nextRight,
5572	>	ObjectToDouble<? super V> transformer,
5573	>	double basis,
5574	>	DoubleByDoubleToDouble reducer) {
5575	>	super(p, b, i, f, t); this.nextRight = nextRight;
5576	>	this.transformer = transformer;
5577	>	this.basis = basis; this.reducer = reducer;
5578	>	}
5579	>	public final Double getRawResult() { return result; }
5580	>	public final void compute() {
5581	>	final ObjectToDouble<? super V> transformer;
5582	>	final DoubleByDoubleToDouble reducer;
5583	>	if ((transformer = this.transformer) != null &&
5584	>	(reducer = this.reducer) != null) {
5585	>	double r = this.basis;
5586	>	for (int i = baseIndex, f, h; batch > 0 &&
5587	>	(h = ((f = baseLimit) + i) >>> 1) > i;) {
5588	>	addToPendingCount(1);
5589	>	(rights = new MapReduceValuesToDoubleTask<K,V>
5590	>	(this, batch >>>= 1, baseLimit = h, f, tab,
5591	>	rights, transformer, r, reducer)).fork();
5592	>	}
5593	>	for (Node<K,V> p; (p = advance()) != null; )
5594	>	r = reducer.apply(r, transformer.apply(p.val));
5595	>	result = r;
5596	>	CountedCompleter<?> c;
5597	>	for (c = firstComplete(); c != null; c = c.nextComplete()) {
5598	>	@SuppressWarnings("unchecked") MapReduceValuesToDoubleTask<K,V>
5599	>	t = (MapReduceValuesToDoubleTask<K,V>)c,
5600	>	s = t.rights;
5601	>	while (s != null) {
5602	>	t.result = reducer.apply(t.result, s.result);
5603	>	s = t.rights = s.nextRight;
5604	>	}
5605	>	}
5606	>	}
5607	>	}
5608	>	}
5609	>
5610	>	@SuppressWarnings("serial")
5611	>	static final class MapReduceEntriesToDoubleTask<K,V>
5612	>	extends BulkTask<K,V,Double> {
5613	>	final ObjectToDouble<Map.Entry<K,V>> transformer;
5614	>	final DoubleByDoubleToDouble reducer;
5615	>	final double basis;
5616	>	double result;
5617	>	MapReduceEntriesToDoubleTask<K,V> rights, nextRight;
5618	>	MapReduceEntriesToDoubleTask
5619	>	(BulkTask<K,V,?> p, int b, int i, int f, Node<K,V>[] t,
5620	>	MapReduceEntriesToDoubleTask<K,V> nextRight,
5621	>	ObjectToDouble<Map.Entry<K,V>> transformer,
5622	>	double basis,
5623	>	DoubleByDoubleToDouble reducer) {
5624	>	super(p, b, i, f, t); this.nextRight = nextRight;
5625	>	this.transformer = transformer;
5626	>	this.basis = basis; this.reducer = reducer;
5627	>	}
5628	>	public final Double getRawResult() { return result; }
5629	>	public final void compute() {
5630	>	final ObjectToDouble<Map.Entry<K,V>> transformer;
5631	>	final DoubleByDoubleToDouble reducer;
5632	>	if ((transformer = this.transformer) != null &&
5633	>	(reducer = this.reducer) != null) {
5634	>	double r = this.basis;
5635	>	for (int i = baseIndex, f, h; batch > 0 &&
5636	>	(h = ((f = baseLimit) + i) >>> 1) > i;) {
5637	>	addToPendingCount(1);
5638	>	(rights = new MapReduceEntriesToDoubleTask<K,V>
5639	>	(this, batch >>>= 1, baseLimit = h, f, tab,
5640	>	rights, transformer, r, reducer)).fork();
5641	>	}
5642	>	for (Node<K,V> p; (p = advance()) != null; )
5643	>	r = reducer.apply(r, transformer.apply(p));
5644	>	result = r;
5645	>	CountedCompleter<?> c;
5646	>	for (c = firstComplete(); c != null; c = c.nextComplete()) {
5647	>	@SuppressWarnings("unchecked") MapReduceEntriesToDoubleTask<K,V>
5648	>	t = (MapReduceEntriesToDoubleTask<K,V>)c,
5649	>	s = t.rights;
5650	>	while (s != null) {
5651	>	t.result = reducer.apply(t.result, s.result);
5652	>	s = t.rights = s.nextRight;
5653	>	}
5654	>	}
5655	>	}
5656	>	}
5657	>	}
5658	>
5659	>	@SuppressWarnings("serial")
5660	>	static final class MapReduceMappingsToDoubleTask<K,V>
5661	>	extends BulkTask<K,V,Double> {
5662	>	final ObjectByObjectToDouble<? super K, ? super V> transformer;
5663	>	final DoubleByDoubleToDouble reducer;
5664	>	final double basis;
5665	>	double result;
5666	>	MapReduceMappingsToDoubleTask<K,V> rights, nextRight;
5667	>	MapReduceMappingsToDoubleTask
5668	>	(BulkTask<K,V,?> p, int b, int i, int f, Node<K,V>[] t,
5669	>	MapReduceMappingsToDoubleTask<K,V> nextRight,
5670	>	ObjectByObjectToDouble<? super K, ? super V> transformer,
5671	>	double basis,
5672	>	DoubleByDoubleToDouble reducer) {
5673	>	super(p, b, i, f, t); this.nextRight = nextRight;
5674	>	this.transformer = transformer;
5675	>	this.basis = basis; this.reducer = reducer;
5676	>	}
5677	>	public final Double getRawResult() { return result; }
5678	>	public final void compute() {
5679	>	final ObjectByObjectToDouble<? super K, ? super V> transformer;
5680	>	final DoubleByDoubleToDouble reducer;
5681	>	if ((transformer = this.transformer) != null &&
5682	>	(reducer = this.reducer) != null) {
5683	>	double r = this.basis;
5684	>	for (int i = baseIndex, f, h; batch > 0 &&
5685	>	(h = ((f = baseLimit) + i) >>> 1) > i;) {
5686	>	addToPendingCount(1);
5687	>	(rights = new MapReduceMappingsToDoubleTask<K,V>
5688	>	(this, batch >>>= 1, baseLimit = h, f, tab,
5689	>	rights, transformer, r, reducer)).fork();
5690	>	}
5691	>	for (Node<K,V> p; (p = advance()) != null; )
5692	>	r = reducer.apply(r, transformer.apply(p.key, p.val));
5693	>	result = r;
5694	>	CountedCompleter<?> c;
5695	>	for (c = firstComplete(); c != null; c = c.nextComplete()) {
5696	>	@SuppressWarnings("unchecked") MapReduceMappingsToDoubleTask<K,V>
5697	>	t = (MapReduceMappingsToDoubleTask<K,V>)c,
5698	>	s = t.rights;
5699	>	while (s != null) {
5700	>	t.result = reducer.apply(t.result, s.result);
5701	>	s = t.rights = s.nextRight;
5702	>	}
5703	>	}
5704	>	}
5705	>	}
5706	>	}
5707	>
5708	>	@SuppressWarnings("serial")
5709	>	static final class MapReduceKeysToLongTask<K,V>
5710	>	extends BulkTask<K,V,Long> {
5711	>	final ObjectToLong<? super K> transformer;
5712	>	final LongByLongToLong reducer;
5713	>	final long basis;
5714	>	long result;
5715	>	MapReduceKeysToLongTask<K,V> rights, nextRight;
5716	>	MapReduceKeysToLongTask
5717	>	(BulkTask<K,V,?> p, int b, int i, int f, Node<K,V>[] t,
5718	>	MapReduceKeysToLongTask<K,V> nextRight,
5719	>	ObjectToLong<? super K> transformer,
5720	>	long basis,
5721	>	LongByLongToLong reducer) {
5722	>	super(p, b, i, f, t); this.nextRight = nextRight;
5723	>	this.transformer = transformer;
5724	>	this.basis = basis; this.reducer = reducer;
5725	>	}
5726	>	public final Long getRawResult() { return result; }
5727	>	public final void compute() {
5728	>	final ObjectToLong<? super K> transformer;
5729	>	final LongByLongToLong reducer;
5730	>	if ((transformer = this.transformer) != null &&
5731	>	(reducer = this.reducer) != null) {
5732	>	long r = this.basis;
5733	>	for (int i = baseIndex, f, h; batch > 0 &&
5734	>	(h = ((f = baseLimit) + i) >>> 1) > i;) {
5735	>	addToPendingCount(1);
5736	>	(rights = new MapReduceKeysToLongTask<K,V>
5737	>	(this, batch >>>= 1, baseLimit = h, f, tab,
5738	>	rights, transformer, r, reducer)).fork();
5739	>	}
5740	>	for (Node<K,V> p; (p = advance()) != null; )
5741	>	r = reducer.apply(r, transformer.apply(p.key));
5742	>	result = r;
5743	>	CountedCompleter<?> c;
5744	>	for (c = firstComplete(); c != null; c = c.nextComplete()) {
5745	>	@SuppressWarnings("unchecked") MapReduceKeysToLongTask<K,V>
5746	>	t = (MapReduceKeysToLongTask<K,V>)c,
5747	>	s = t.rights;
5748	>	while (s != null) {
5749	>	t.result = reducer.apply(t.result, s.result);
5750	>	s = t.rights = s.nextRight;
5751	>	}
5752	>	}
5753	>	}
5754	>	}
5755	>	}
5756	>
5757	>	@SuppressWarnings("serial")
5758	>	static final class MapReduceValuesToLongTask<K,V>
5759	>	extends BulkTask<K,V,Long> {
5760	>	final ObjectToLong<? super V> transformer;
5761	>	final LongByLongToLong reducer;
5762	>	final long basis;
5763	>	long result;
5764	>	MapReduceValuesToLongTask<K,V> rights, nextRight;
5765	>	MapReduceValuesToLongTask
5766	>	(BulkTask<K,V,?> p, int b, int i, int f, Node<K,V>[] t,
5767	>	MapReduceValuesToLongTask<K,V> nextRight,
5768	>	ObjectToLong<? super V> transformer,
5769	>	long basis,
5770	>	LongByLongToLong reducer) {
5771	>	super(p, b, i, f, t); this.nextRight = nextRight;
5772	>	this.transformer = transformer;
5773	>	this.basis = basis; this.reducer = reducer;
5774	>	}
5775	>	public final Long getRawResult() { return result; }
5776	>	public final void compute() {
5777	>	final ObjectToLong<? super V> transformer;
5778	>	final LongByLongToLong reducer;
5779	>	if ((transformer = this.transformer) != null &&
5780	>	(reducer = this.reducer) != null) {
5781	>	long r = this.basis;
5782	>	for (int i = baseIndex, f, h; batch > 0 &&
5783	>	(h = ((f = baseLimit) + i) >>> 1) > i;) {
5784	>	addToPendingCount(1);
5785	>	(rights = new MapReduceValuesToLongTask<K,V>
5786	>	(this, batch >>>= 1, baseLimit = h, f, tab,
5787	>	rights, transformer, r, reducer)).fork();
5788	>	}
5789	>	for (Node<K,V> p; (p = advance()) != null; )
5790	>	r = reducer.apply(r, transformer.apply(p.val));
5791	>	result = r;
5792	>	CountedCompleter<?> c;
5793	>	for (c = firstComplete(); c != null; c = c.nextComplete()) {
5794	>	@SuppressWarnings("unchecked") MapReduceValuesToLongTask<K,V>
5795	>	t = (MapReduceValuesToLongTask<K,V>)c,
5796	>	s = t.rights;
5797	>	while (s != null) {
5798	>	t.result = reducer.apply(t.result, s.result);
5799	>	s = t.rights = s.nextRight;
5800	>	}
5801	>	}
5802	>	}
5803	>	}
5804	>	}
5805	>
5806	>	@SuppressWarnings("serial")
5807	>	static final class MapReduceEntriesToLongTask<K,V>
5808	>	extends BulkTask<K,V,Long> {
5809	>	final ObjectToLong<Map.Entry<K,V>> transformer;
5810	>	final LongByLongToLong reducer;
5811	>	final long basis;
5812	>	long result;
5813	>	MapReduceEntriesToLongTask<K,V> rights, nextRight;
5814	>	MapReduceEntriesToLongTask
5815	>	(BulkTask<K,V,?> p, int b, int i, int f, Node<K,V>[] t,
5816	>	MapReduceEntriesToLongTask<K,V> nextRight,
5817	>	ObjectToLong<Map.Entry<K,V>> transformer,
5818	>	long basis,
5819	>	LongByLongToLong reducer) {
5820	>	super(p, b, i, f, t); this.nextRight = nextRight;
5821	>	this.transformer = transformer;
5822	>	this.basis = basis; this.reducer = reducer;
5823	>	}
5824	>	public final Long getRawResult() { return result; }
5825	>	public final void compute() {
5826	>	final ObjectToLong<Map.Entry<K,V>> transformer;
5827	>	final LongByLongToLong reducer;
5828	>	if ((transformer = this.transformer) != null &&
5829	>	(reducer = this.reducer) != null) {
5830	>	long r = this.basis;
5831	>	for (int i = baseIndex, f, h; batch > 0 &&
5832	>	(h = ((f = baseLimit) + i) >>> 1) > i;) {
5833	>	addToPendingCount(1);
5834	>	(rights = new MapReduceEntriesToLongTask<K,V>
5835	>	(this, batch >>>= 1, baseLimit = h, f, tab,
5836	>	rights, transformer, r, reducer)).fork();
5837	>	}
5838	>	for (Node<K,V> p; (p = advance()) != null; )
5839	>	r = reducer.apply(r, transformer.apply(p));
5840	>	result = r;
5841	>	CountedCompleter<?> c;
5842	>	for (c = firstComplete(); c != null; c = c.nextComplete()) {
5843	>	@SuppressWarnings("unchecked") MapReduceEntriesToLongTask<K,V>
5844	>	t = (MapReduceEntriesToLongTask<K,V>)c,
5845	>	s = t.rights;
5846	>	while (s != null) {
5847	>	t.result = reducer.apply(t.result, s.result);
5848	>	s = t.rights = s.nextRight;
5849	>	}
5850	>	}
5851	>	}
5852	>	}
5853	>	}
5854	>
5855	>	@SuppressWarnings("serial")
5856	>	static final class MapReduceMappingsToLongTask<K,V>
5857	>	extends BulkTask<K,V,Long> {
5858	>	final ObjectByObjectToLong<? super K, ? super V> transformer;
5859	>	final LongByLongToLong reducer;
5860	>	final long basis;
5861	>	long result;
5862	>	MapReduceMappingsToLongTask<K,V> rights, nextRight;
5863	>	MapReduceMappingsToLongTask
5864	>	(BulkTask<K,V,?> p, int b, int i, int f, Node<K,V>[] t,
5865	>	MapReduceMappingsToLongTask<K,V> nextRight,
5866	>	ObjectByObjectToLong<? super K, ? super V> transformer,
5867	>	long basis,
5868	>	LongByLongToLong reducer) {
5869	>	super(p, b, i, f, t); this.nextRight = nextRight;
5870	>	this.transformer = transformer;
5871	>	this.basis = basis; this.reducer = reducer;
5872	>	}
5873	>	public final Long getRawResult() { return result; }
5874	>	public final void compute() {
5875	>	final ObjectByObjectToLong<? super K, ? super V> transformer;
5876	>	final LongByLongToLong reducer;
5877	>	if ((transformer = this.transformer) != null &&
5878	>	(reducer = this.reducer) != null) {
5879	>	long r = this.basis;
5880	>	for (int i = baseIndex, f, h; batch > 0 &&
5881	>	(h = ((f = baseLimit) + i) >>> 1) > i;) {
5882	>	addToPendingCount(1);
5883	>	(rights = new MapReduceMappingsToLongTask<K,V>
5884	>	(this, batch >>>= 1, baseLimit = h, f, tab,
5885	>	rights, transformer, r, reducer)).fork();
5886	>	}
5887	>	for (Node<K,V> p; (p = advance()) != null; )
5888	>	r = reducer.apply(r, transformer.apply(p.key, p.val));
5889	>	result = r;
5890	>	CountedCompleter<?> c;
5891	>	for (c = firstComplete(); c != null; c = c.nextComplete()) {
5892	>	@SuppressWarnings("unchecked") MapReduceMappingsToLongTask<K,V>
5893	>	t = (MapReduceMappingsToLongTask<K,V>)c,
5894	>	s = t.rights;
5895	>	while (s != null) {
5896	>	t.result = reducer.apply(t.result, s.result);
5897	>	s = t.rights = s.nextRight;
5898	>	}
5899	>	}
5900	>	}
5901	>	}
5902	>	}
5903	>
5904	>	@SuppressWarnings("serial")
5905	>	static final class MapReduceKeysToIntTask<K,V>
5906	>	extends BulkTask<K,V,Integer> {
5907	>	final ObjectToInt<? super K> transformer;
5908	>	final IntByIntToInt reducer;
5909	>	final int basis;
5910	>	int result;
5911	>	MapReduceKeysToIntTask<K,V> rights, nextRight;
5912	>	MapReduceKeysToIntTask
5913	>	(BulkTask<K,V,?> p, int b, int i, int f, Node<K,V>[] t,
5914	>	MapReduceKeysToIntTask<K,V> nextRight,
5915	>	ObjectToInt<? super K> transformer,
5916	>	int basis,
5917	>	IntByIntToInt reducer) {
5918	>	super(p, b, i, f, t); this.nextRight = nextRight;
5919	>	this.transformer = transformer;
5920	>	this.basis = basis; this.reducer = reducer;
5921	>	}
5922	>	public final Integer getRawResult() { return result; }
5923	>	public final void compute() {
5924	>	final ObjectToInt<? super K> transformer;
5925	>	final IntByIntToInt reducer;
5926	>	if ((transformer = this.transformer) != null &&
5927	>	(reducer = this.reducer) != null) {
5928	>	int r = this.basis;
5929	>	for (int i = baseIndex, f, h; batch > 0 &&
5930	>	(h = ((f = baseLimit) + i) >>> 1) > i;) {
5931	>	addToPendingCount(1);
5932	>	(rights = new MapReduceKeysToIntTask<K,V>
5933	>	(this, batch >>>= 1, baseLimit = h, f, tab,
5934	>	rights, transformer, r, reducer)).fork();
5935	>	}
5936	>	for (Node<K,V> p; (p = advance()) != null; )
5937	>	r = reducer.apply(r, transformer.apply(p.key));
5938	>	result = r;
5939	>	CountedCompleter<?> c;
5940	>	for (c = firstComplete(); c != null; c = c.nextComplete()) {
5941	>	@SuppressWarnings("unchecked") MapReduceKeysToIntTask<K,V>
5942	>	t = (MapReduceKeysToIntTask<K,V>)c,
5943	>	s = t.rights;
5944	>	while (s != null) {
5945	>	t.result = reducer.apply(t.result, s.result);
5946	>	s = t.rights = s.nextRight;
5947	>	}
5948	>	}
5949	>	}
5950	>	}
5951	>	}
5952	>
5953	>	@SuppressWarnings("serial")
5954	>	static final class MapReduceValuesToIntTask<K,V>
5955	>	extends BulkTask<K,V,Integer> {
5956	>	final ObjectToInt<? super V> transformer;
5957	>	final IntByIntToInt reducer;
5958	>	final int basis;
5959	>	int result;
5960	>	MapReduceValuesToIntTask<K,V> rights, nextRight;
5961	>	MapReduceValuesToIntTask
5962	>	(BulkTask<K,V,?> p, int b, int i, int f, Node<K,V>[] t,
5963	>	MapReduceValuesToIntTask<K,V> nextRight,
5964	>	ObjectToInt<? super V> transformer,
5965	>	int basis,
5966	>	IntByIntToInt reducer) {
5967	>	super(p, b, i, f, t); this.nextRight = nextRight;
5968	>	this.transformer = transformer;
5969	>	this.basis = basis; this.reducer = reducer;
5970	>	}
5971	>	public final Integer getRawResult() { return result; }
5972	>	public final void compute() {
5973	>	final ObjectToInt<? super V> transformer;
5974	>	final IntByIntToInt reducer;
5975	>	if ((transformer = this.transformer) != null &&
5976	>	(reducer = this.reducer) != null) {
5977	>	int r = this.basis;
5978	>	for (int i = baseIndex, f, h; batch > 0 &&
5979	>	(h = ((f = baseLimit) + i) >>> 1) > i;) {
5980	>	addToPendingCount(1);
5981	>	(rights = new MapReduceValuesToIntTask<K,V>
5982	>	(this, batch >>>= 1, baseLimit = h, f, tab,
5983	>	rights, transformer, r, reducer)).fork();
5984	>	}
5985	>	for (Node<K,V> p; (p = advance()) != null; )
5986	>	r = reducer.apply(r, transformer.apply(p.val));
5987	>	result = r;
5988	>	CountedCompleter<?> c;
5989	>	for (c = firstComplete(); c != null; c = c.nextComplete()) {
5990	>	@SuppressWarnings("unchecked") MapReduceValuesToIntTask<K,V>
5991	>	t = (MapReduceValuesToIntTask<K,V>)c,
5992	>	s = t.rights;
5993	>	while (s != null) {
5994	>	t.result = reducer.apply(t.result, s.result);
5995	>	s = t.rights = s.nextRight;
5996	>	}
5997	>	}
5998	>	}
5999	>	}
6000	>	}
6001	>
6002	>	@SuppressWarnings("serial")
6003	>	static final class MapReduceEntriesToIntTask<K,V>
6004	>	extends BulkTask<K,V,Integer> {
6005	>	final ObjectToInt<Map.Entry<K,V>> transformer;
6006	>	final IntByIntToInt reducer;
6007	>	final int basis;
6008	>	int result;
6009	>	MapReduceEntriesToIntTask<K,V> rights, nextRight;
6010	>	MapReduceEntriesToIntTask
6011	>	(BulkTask<K,V,?> p, int b, int i, int f, Node<K,V>[] t,
6012	>	MapReduceEntriesToIntTask<K,V> nextRight,
6013	>	ObjectToInt<Map.Entry<K,V>> transformer,
6014	>	int basis,
6015	>	IntByIntToInt reducer) {
6016	>	super(p, b, i, f, t); this.nextRight = nextRight;
6017	>	this.transformer = transformer;
6018	>	this.basis = basis; this.reducer = reducer;
6019	>	}
6020	>	public final Integer getRawResult() { return result; }
6021	>	public final void compute() {
6022	>	final ObjectToInt<Map.Entry<K,V>> transformer;
6023	>	final IntByIntToInt reducer;
6024	>	if ((transformer = this.transformer) != null &&
6025	>	(reducer = this.reducer) != null) {
6026	>	int r = this.basis;
6027	>	for (int i = baseIndex, f, h; batch > 0 &&
6028	>	(h = ((f = baseLimit) + i) >>> 1) > i;) {
6029	>	addToPendingCount(1);
6030	>	(rights = new MapReduceEntriesToIntTask<K,V>
6031	>	(this, batch >>>= 1, baseLimit = h, f, tab,
6032	>	rights, transformer, r, reducer)).fork();
6033	>	}
6034	>	for (Node<K,V> p; (p = advance()) != null; )
6035	>	r = reducer.apply(r, transformer.apply(p));
6036	>	result = r;
6037	>	CountedCompleter<?> c;
6038	>	for (c = firstComplete(); c != null; c = c.nextComplete()) {
6039	>	@SuppressWarnings("unchecked") MapReduceEntriesToIntTask<K,V>
6040	>	t = (MapReduceEntriesToIntTask<K,V>)c,
6041	>	s = t.rights;
6042	>	while (s != null) {
6043	>	t.result = reducer.apply(t.result, s.result);
6044	>	s = t.rights = s.nextRight;
6045	>	}
6046	>	}
6047	>	}
6048	>	}
6049	>	}
6050	>
6051	>	@SuppressWarnings("serial")
6052	>	static final class MapReduceMappingsToIntTask<K,V>
6053	>	extends BulkTask<K,V,Integer> {
6054	>	final ObjectByObjectToInt<? super K, ? super V> transformer;
6055	>	final IntByIntToInt reducer;
6056	>	final int basis;
6057	>	int result;
6058	>	MapReduceMappingsToIntTask<K,V> rights, nextRight;
6059	>	MapReduceMappingsToIntTask
6060	>	(BulkTask<K,V,?> p, int b, int i, int f, Node<K,V>[] t,
6061	>	MapReduceMappingsToIntTask<K,V> nextRight,
6062	>	ObjectByObjectToInt<? super K, ? super V> transformer,
6063	>	int basis,
6064	>	IntByIntToInt reducer) {
6065	>	super(p, b, i, f, t); this.nextRight = nextRight;
6066	>	this.transformer = transformer;
6067	>	this.basis = basis; this.reducer = reducer;
6068	>	}
6069	>	public final Integer getRawResult() { return result; }
6070	>	public final void compute() {
6071	>	final ObjectByObjectToInt<? super K, ? super V> transformer;
6072	>	final IntByIntToInt reducer;
6073	>	if ((transformer = this.transformer) != null &&
6074	>	(reducer = this.reducer) != null) {
6075	>	int r = this.basis;
6076	>	for (int i = baseIndex, f, h; batch > 0 &&
6077	>	(h = ((f = baseLimit) + i) >>> 1) > i;) {
6078	>	addToPendingCount(1);
6079	>	(rights = new MapReduceMappingsToIntTask<K,V>
6080	>	(this, batch >>>= 1, baseLimit = h, f, tab,
6081	>	rights, transformer, r, reducer)).fork();
6082	>	}
6083	>	for (Node<K,V> p; (p = advance()) != null; )
6084	>	r = reducer.apply(r, transformer.apply(p.key, p.val));
6085	>	result = r;
6086	>	CountedCompleter<?> c;
6087	>	for (c = firstComplete(); c != null; c = c.nextComplete()) {
6088	>	@SuppressWarnings("unchecked") MapReduceMappingsToIntTask<K,V>
6089	>	t = (MapReduceMappingsToIntTask<K,V>)c,
6090	>	s = t.rights;
6091	>	while (s != null) {
6092	>	t.result = reducer.apply(t.result, s.result);
6093	>	s = t.rights = s.nextRight;
6094	>	}
6095	>	}
6096	>	}
6097	>	}
6098	>	}
6099	>
6100	>	/* ---------------- Counters -------------- */
6101	>
6102	>	// Adapted from LongAdder and Striped64.
6103	>	// See their internal docs for explanation.
6104	>
6105	>	// A padded cell for distributing counts
6106	>	static final class CounterCell {
6107	>	volatile long p0, p1, p2, p3, p4, p5, p6;
6108	>	volatile long value;
6109	>	volatile long q0, q1, q2, q3, q4, q5, q6;
6110	>	CounterCell(long x) { value = x; }
6111	>	}
6112	>
6113	>	/**
6114	>	* Holder for the thread-local hash code determining which
6115	>	* CounterCell to use. The code is initialized via the
6116	>	* counterHashCodeGenerator, but may be moved upon collisions.
6117	>	*/
6118	>	static final class CounterHashCode {
6119	>	int code;
6120	>	}
6121	>
6122	>	/**
6123	>	* Generates initial value for per-thread CounterHashCodes.
6124	>	*/
6125	>	static final AtomicInteger counterHashCodeGenerator = new AtomicInteger();
6126	>
6127	>	/**
6128	>	* Increment for counterHashCodeGenerator. See class ThreadLocal
6129	>	* for explanation.
6130	>	*/
6131	>	static final int SEED_INCREMENT = 0x61c88647;
6132	>
6133	>	/**
6134	>	* Per-thread counter hash codes. Shared across all instances.
6135	>	*/
6136	>	static final ThreadLocal<CounterHashCode> threadCounterHashCode =
6137	>	new ThreadLocal<CounterHashCode>();
6138	>
6139	>
6140	>	final long sumCount() {
6141	>	CounterCell[] as = counterCells; CounterCell a;
6142	>	long sum = baseCount;
6143	>	if (as != null) {
6144	>	for (int i = 0; i < as.length; ++i) {
6145	>	if ((a = as[i]) != null)
6146	>	sum += a.value;
6147	>	}
6148	>	}
6149	>	return sum;
6150	>	}
6151	>
6152	>	// See LongAdder version for explanation
6153	>	private final void fullAddCount(long x, CounterHashCode hc,
6154	>	boolean wasUncontended) {
6155	>	int h;
6156	>	if (hc == null) {
6157	>	hc = new CounterHashCode();
6158	>	int s = counterHashCodeGenerator.addAndGet(SEED_INCREMENT);
6159	>	h = hc.code = (s == 0) ? 1 : s; // Avoid zero
6160	>	threadCounterHashCode.set(hc);
6161	>	}
6162	>	else
6163	>	h = hc.code;
6164	>	boolean collide = false;                // True if last slot nonempty
6165	>	for (;;) {
6166	>	CounterCell[] as; CounterCell a; int n; long v;
6167	>	if ((as = counterCells) != null && (n = as.length) > 0) {
6168	>	if ((a = as[(n - 1) & h]) == null) {
6169	>	if (cellsBusy == 0) {            // Try to attach new Cell
6170	>	CounterCell r = new CounterCell(x); // Optimistic create
6171	>	if (cellsBusy == 0 &&
6172	>	U.compareAndSwapInt(this, CELLSBUSY, 0, 1)) {
6173	>	boolean created = false;
6174	>	try {               // Recheck under lock
6175	>	CounterCell[] rs; int m, j;
6176	>	if ((rs = counterCells) != null &&
6177	>	(m = rs.length) > 0 &&
6178	>	rs[j = (m - 1) & h] == null) {
6179	>	rs[j] = r;
6180	>	created = true;
6181	>	}
6182	>	} finally {
6183	>	cellsBusy = 0;
6184	>	}
6185	>	if (created)
6186	>	break;
6187	>	continue;           // Slot is now non-empty
6188		}
3267	–	table = tab;
3268	–	counter.add(size);
3269	–	sc = n - (n >>> 2);
6189		}
6190	<	} finally {
3272	<	sizeCtl = sc;
6190	>	collide = false;
6191		}
6192	<	if (collide) { // rescan and convert to TreeBins
6193	<	Node[] tab = table;
6194	<	for (int i = 0; i < tab.length; ++i) {
6195	<	int c = 0;
6196	<	for (Node e = tabAt(tab, i); e != null; e = e.next) {
6197	<	if (++c > TREE_THRESHOLD &&
6198	<	(e.key instanceof Comparable)) {
6199	<	replaceWithTreeBin(tab, i, e.key);
6200	<	break;
6201	<	}
6192	>	else if (!wasUncontended)       // CAS already known to fail
6193	>	wasUncontended = true;      // Continue after rehash
6194	>	else if (U.compareAndSwapLong(a, CELLVALUE, v = a.value, v + x))
6195	>	break;
6196	>	else if (counterCells != as || n >= NCPU)
6197	>	collide = false;            // At max size or stale
6198	>	else if (!collide)
6199	>	collide = true;
6200	>	else if (cellsBusy == 0 &&
6201	>	U.compareAndSwapInt(this, CELLSBUSY, 0, 1)) {
6202	>	try {
6203	>	if (counterCells == as) {// Expand table unless stale
6204	>	CounterCell[] rs = new CounterCell[n << 1];
6205	>	for (int i = 0; i < n; ++i)
6206	>	rs[i] = as[i];
6207	>	counterCells = rs;
6208		}
6209	+	} finally {
6210	+	cellsBusy = 0;
6211		}
6212	+	collide = false;
6213	+	continue;                   // Retry with expanded table
6214		}
6215	<	}
6216	<	if (!init) { // Can only happen if unsafely published.
6217	<	while (p != null) {
6218	<	internalPut(p.key, p.val);
6219	<	p = p.next;
6215	>	h ^= h << 13;                   // Rehash
6216	>	h ^= h >>> 17;
6217	>	h ^= h << 5;
6218	>	}
6219	>	else if (cellsBusy == 0 && counterCells == as &&
6220	>	U.compareAndSwapInt(this, CELLSBUSY, 0, 1)) {
6221	>	boolean init = false;
6222	>	try {                           // Initialize table
6223	>	if (counterCells == as) {
6224	>	CounterCell[] rs = new CounterCell[2];
6225	>	rs[h & 1] = new CounterCell(x);
6226	>	counterCells = rs;
6227	>	init = true;
6228	>	}
6229	>	} finally {
6230	>	cellsBusy = 0;
6231		}
6232	+	if (init)
6233	+	break;
6234		}
6235	+	else if (U.compareAndSwapLong(this, BASECOUNT, v = baseCount, v + x))
6236	+	break;                          // Fall back on using base
6237		}
6238	+	hc.code = h;                            // Record index for next time
6239		}
6240
6241		// Unsafe mechanics
6242	<	private static final sun.misc.Unsafe UNSAFE;
6243	<	private static final long counterOffset;
6244	<	private static final long sizeCtlOffset;
6242	>	private static final sun.misc.Unsafe U;
6243	>	private static final long SIZECTL;
6244	>	private static final long TRANSFERINDEX;
6245	>	private static final long BASECOUNT;
6246	>	private static final long CELLSBUSY;
6247	>	private static final long CELLVALUE;
6248		private static final long ABASE;
6249		private static final int ASHIFT;
6250
6251		static {
3305	–	int ss;
6252		try {
6253	<	UNSAFE = getUnsafe();
6253	>	U = getUnsafe();
6254		Class<?> k = ConcurrentHashMapV8.class;
6255	<	counterOffset = UNSAFE.objectFieldOffset
3310	<	(k.getDeclaredField("counter"));
3311	<	sizeCtlOffset = UNSAFE.objectFieldOffset
6255	>	SIZECTL = U.objectFieldOffset
6256		(k.getDeclaredField("sizeCtl"));
6257	<	Class<?> sc = Node[].class;
6258	<	ABASE = UNSAFE.arrayBaseOffset(sc);
6259	<	ss = UNSAFE.arrayIndexScale(sc);
6257	>	TRANSFERINDEX = U.objectFieldOffset
6258	>	(k.getDeclaredField("transferIndex"));
6259	>	BASECOUNT = U.objectFieldOffset
6260	>	(k.getDeclaredField("baseCount"));
6261	>	CELLSBUSY = U.objectFieldOffset
6262	>	(k.getDeclaredField("cellsBusy"));
6263	>	Class<?> ck = CounterCell.class;
6264	>	CELLVALUE = U.objectFieldOffset
6265	>	(ck.getDeclaredField("value"));
6266	>	Class<?> ak = Node[].class;
6267	>	ABASE = U.arrayBaseOffset(ak);
6268	>	int scale = U.arrayIndexScale(ak);
6269	>	if ((scale & (scale - 1)) != 0)
6270	>	throw new Error("data type scale not a power of two");
6271	>	ASHIFT = 31 - Integer.numberOfLeadingZeros(scale);
6272		} catch (Exception e) {
6273		throw new Error(e);
6274		}
3319	–	if ((ss & (ss-1)) != 0)
3320	–	throw new Error("data type scale not a power of two");
3321	–	ASHIFT = 31 - Integer.numberOfLeadingZeros(ss);
6275		}
6276
6277		/**
#	Line 3331 | Line 6284 | public class ConcurrentHashMapV8<K, V>
6284		private static sun.misc.Unsafe getUnsafe() {
6285		try {
6286		return sun.misc.Unsafe.getUnsafe();
6287	<	} catch (SecurityException se) {
6288	<	try {
6289	<	return java.security.AccessController.doPrivileged
6290	<	(new java.security
6291	<	.PrivilegedExceptionAction<sun.misc.Unsafe>() {
6292	<	public sun.misc.Unsafe run() throws Exception {
6293	<	java.lang.reflect.Field f = sun.misc
6294	<	.Unsafe.class.getDeclaredField("theUnsafe");
6295	<	f.setAccessible(true);
6296	<	return (sun.misc.Unsafe) f.get(null);
6297	<	}});
6298	<	} catch (java.security.PrivilegedActionException e) {
6299	<	throw new RuntimeException("Could not initialize intrinsics",
6300	<	e.getCause());
6301	<	}
6287	>	} catch (SecurityException tryReflectionInstead) {}
6288	>	try {
6289	>	return java.security.AccessController.doPrivileged
6290	>	(new java.security.PrivilegedExceptionAction<sun.misc.Unsafe>() {
6291	>	public sun.misc.Unsafe run() throws Exception {
6292	>	Class<sun.misc.Unsafe> k = sun.misc.Unsafe.class;
6293	>	for (java.lang.reflect.Field f : k.getDeclaredFields()) {
6294	>	f.setAccessible(true);
6295	>	Object x = f.get(null);
6296	>	if (k.isInstance(x))
6297	>	return k.cast(x);
6298	>	}
6299	>	throw new NoSuchFieldError("the Unsafe");
6300	>	}});
6301	>	} catch (java.security.PrivilegedActionException e) {
6302	>	throw new RuntimeException("Could not initialize intrinsics",
6303	>	e.getCause());
6304		}
6305		}
3351	–
6306		}

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