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Comparing jsr166/src/jsr166e/ConcurrentHashMapV8.java (file contents):
Revision 1.50 by jsr166, Sat Jul 7 13:01:53 2012 UTC vs.
Revision 1.121 by jsr166, Sat Dec 21 21:32:34 2013 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;
20	<	import java.util.AbstractCollection;
16	<	import java.util.Hashtable;
18	>	import java.util.Comparator;
19	>	import java.util.ConcurrentModificationException;
20	>	import java.util.Enumeration;
21		import java.util.HashMap;
22	+	import java.util.Hashtable;
23		import java.util.Iterator;
24	<	import java.util.Enumeration;
20	<	import java.util.ConcurrentModificationException;
24	>	import java.util.Map;
25		import java.util.NoSuchElementException;
26	+	import java.util.Set;
27		import java.util.concurrent.ConcurrentMap;
28	<	import java.util.concurrent.ThreadLocalRandom;
28	>	import java.util.concurrent.atomic.AtomicReference;
29	>	import java.util.concurrent.atomic.AtomicInteger;
30		import java.util.concurrent.locks.LockSupport;
31	<	import java.util.concurrent.locks.AbstractQueuedSynchronizer;
26	<	import java.io.Serializable;
31	>	import java.util.concurrent.locks.ReentrantLock;
32
33		/**
34		* A hash table supporting full concurrency of retrievals and
#	Line 37 | Line 42 | import java.io.Serializable;
42		* interoperable with {@code Hashtable} in programs that rely on its
43		* thread safety but not on its synchronization details.
44		*
45	<	* <p> Retrieval operations (including {@code get}) generally do not
45	>	* <p>Retrieval operations (including {@code get}) generally do not
46		* block, so may overlap with update operations (including {@code put}
47		* and {@code remove}). Retrievals reflect the results of the most
48		* recently <em>completed</em> update operations holding upon their
49	<	* onset.  For aggregate operations such as {@code putAll} and {@code
50	<	* clear}, concurrent retrievals may reflect insertion or removal of
51	<	* only some entries.  Similarly, Iterators and Enumerations return
52	<	* elements reflecting the state of the hash table at some point at or
53	<	* since the creation of the iterator/enumeration.  They do
54	<	* <em>not</em> throw {@link ConcurrentModificationException}.
55	<	* However, iterators are designed to be used by only one thread at a
56	<	* time.  Bear in mind that the results of aggregate status methods
57	<	* including {@code size}, {@code isEmpty}, and {@code containsValue}
58	<	* are typically useful only when a map is not undergoing concurrent
59	<	* updates in other threads.  Otherwise the results of these methods
60	<	* reflect transient states that may be adequate for monitoring
61	<	* or estimation purposes, but not for program control.
49	>	* onset. (More formally, an update operation for a given key bears a
50	>	* <em>happens-before</em> relation with any (non-null) retrieval for
51	>	* that key reporting the updated value.)  For aggregate operations
52	>	* such as {@code putAll} and {@code clear}, concurrent retrievals may
53	>	* reflect insertion or removal of only some entries.  Similarly,
54	>	* Iterators and Enumerations return elements reflecting the state of
55	>	* the hash table at some point at or since the creation of the
56	>	* iterator/enumeration.  They do <em>not</em> throw {@link
57	>	* ConcurrentModificationException}.  However, iterators are designed
58	>	* to be used by only one thread at a time.  Bear in mind that the
59	>	* results of aggregate status methods including {@code size}, {@code
60	>	* isEmpty}, and {@code containsValue} are typically useful only when
61	>	* a map is not undergoing concurrent updates in other threads.
62	>	* Otherwise the results of these methods reflect transient states
63	>	* that may be adequate for monitoring or estimation purposes, but not
64	>	* for program control.
65		*
66	<	* <p> The table is dynamically expanded when there are too many
66	>	* <p>The table is dynamically expanded when there are too many
67		* collisions (i.e., keys that have distinct hash codes but fall into
68		* the same slot modulo the table size), with the expected average
69		* effect of maintaining roughly two bins per mapping (corresponding
#	Line 74 | Line 82 | import java.io.Serializable;
82		* expected {@code concurrencyLevel} as an additional hint for
83		* internal sizing.  Note that using many keys with exactly the same
84		* {@code hashCode()} is a sure way to slow down performance of any
85	<	* hash table.
85	>	* hash table. To ameliorate impact, when keys are {@link Comparable},
86	>	* this class may use comparison order among keys to help break ties.
87	>	*
88	>	* <p>A {@link Set} projection of a ConcurrentHashMapV8 may be created
89	>	* (using {@link #newKeySet()} or {@link #newKeySet(int)}), or viewed
90	>	* (using {@link #keySet(Object)} when only keys are of interest, and the
91	>	* mapped values are (perhaps transiently) not used or all take the
92	>	* same mapping value.
93		*
94		* <p>This class and its views and iterators implement all of the
95		* <em>optional</em> methods of the {@link Map} and {@link Iterator}
96		* interfaces.
97		*
98	<	* <p> Like {@link Hashtable} but unlike {@link HashMap}, this class
98	>	* <p>Like {@link Hashtable} but unlike {@link HashMap}, this class
99		* does <em>not</em> allow {@code null} to be used as a key or value.
100		*
101	+	* <p>ConcurrentHashMapV8s support a set of sequential and parallel bulk
102	+	* operations that are designed
103	+	* to be safely, and often sensibly, applied even with maps that are
104	+	* being concurrently updated by other threads; for example, when
105	+	* computing a snapshot summary of the values in a shared registry.
106	+	* There are three kinds of operation, each with four forms, accepting
107	+	* functions with Keys, Values, Entries, and (Key, Value) arguments
108	+	* and/or return values. Because the elements of a ConcurrentHashMapV8
109	+	* are not ordered in any particular way, and may be processed in
110	+	* different orders in different parallel executions, the correctness
111	+	* of supplied functions should not depend on any ordering, or on any
112	+	* other objects or values that may transiently change while
113	+	* computation is in progress; and except for forEach actions, should
114	+	* ideally be side-effect-free. Bulk operations on {@link java.util.Map.Entry}
115	+	* objects do not support method {@code setValue}.
116	+	*
117	+	* <ul>
118	+	* <li> forEach: Perform a given action on each element.
119	+	* A variant form applies a given transformation on each element
120	+	* before performing the action.</li>
121	+	*
122	+	* <li> search: Return the first available non-null result of
123	+	* applying a given function on each element; skipping further
124	+	* search when a result is found.</li>
125	+	*
126	+	* <li> reduce: Accumulate each element.  The supplied reduction
127	+	* function cannot rely on ordering (more formally, it should be
128	+	* both associative and commutative).  There are five variants:
129	+	*
130	+	* <ul>
131	+	*
132	+	* <li> Plain reductions. (There is not a form of this method for
133	+	* (key, value) function arguments since there is no corresponding
134	+	* return type.)</li>
135	+	*
136	+	* <li> Mapped reductions that accumulate the results of a given
137	+	* function applied to each element.</li>
138	+	*
139	+	* <li> Reductions to scalar doubles, longs, and ints, using a
140	+	* given basis value.</li>
141	+	*
142	+	* </ul>
143	+	* </li>
144	+	* </ul>
145	+	*
146	+	* <p>These bulk operations accept a {@code parallelismThreshold}
147	+	* argument. Methods proceed sequentially if the current map size is
148	+	* estimated to be less than the given threshold. Using a value of
149	+	* {@code Long.MAX_VALUE} suppresses all parallelism.  Using a value
150	+	* of {@code 1} results in maximal parallelism by partitioning into
151	+	* enough subtasks to fully utilize the {@link
152	+	* ForkJoinPool#commonPool()} that is used for all parallel
153	+	* computations. Normally, you would initially choose one of these
154	+	* extreme values, and then measure performance of using in-between
155	+	* values that trade off overhead versus throughput.
156	+	*
157	+	* <p>The concurrency properties of bulk operations follow
158	+	* from those of ConcurrentHashMapV8: Any non-null result returned
159	+	* from {@code get(key)} and related access methods bears a
160	+	* happens-before relation with the associated insertion or
161	+	* update.  The result of any bulk operation reflects the
162	+	* composition of these per-element relations (but is not
163	+	* necessarily atomic with respect to the map as a whole unless it
164	+	* is somehow known to be quiescent).  Conversely, because keys
165	+	* and values in the map are never null, null serves as a reliable
166	+	* atomic indicator of the current lack of any result.  To
167	+	* maintain this property, null serves as an implicit basis for
168	+	* all non-scalar reduction operations. For the double, long, and
169	+	* int versions, the basis should be one that, when combined with
170	+	* any other value, returns that other value (more formally, it
171	+	* should be the identity element for the reduction). Most common
172	+	* reductions have these properties; for example, computing a sum
173	+	* with basis 0 or a minimum with basis MAX_VALUE.
174	+	*
175	+	* <p>Search and transformation functions provided as arguments
176	+	* should similarly return null to indicate the lack of any result
177	+	* (in which case it is not used). In the case of mapped
178	+	* reductions, this also enables transformations to serve as
179	+	* filters, returning null (or, in the case of primitive
180	+	* specializations, the identity basis) if the element should not
181	+	* be combined. You can create compound transformations and
182	+	* filterings by composing them yourself under this "null means
183	+	* there is nothing there now" rule before using them in search or
184	+	* reduce operations.
185	+	*
186	+	* <p>Methods accepting and/or returning Entry arguments maintain
187	+	* key-value associations. They may be useful for example when
188	+	* finding the key for the greatest value. Note that "plain" Entry
189	+	* arguments can be supplied using {@code new
190	+	* AbstractMap.SimpleEntry(k,v)}.
191	+	*
192	+	* <p>Bulk operations may complete abruptly, throwing an
193	+	* exception encountered in the application of a supplied
194	+	* function. Bear in mind when handling such exceptions that other
195	+	* concurrently executing functions could also have thrown
196	+	* exceptions, or would have done so if the first exception had
197	+	* not occurred.
198	+	*
199	+	* <p>Speedups for parallel compared to sequential forms are common
200	+	* but not guaranteed.  Parallel operations involving brief functions
201	+	* on small maps may execute more slowly than sequential forms if the
202	+	* underlying work to parallelize the computation is more expensive
203	+	* than the computation itself.  Similarly, parallelization may not
204	+	* lead to much actual parallelism if all processors are busy
205	+	* performing unrelated tasks.
206	+	*
207	+	* <p>All arguments to all task methods must be non-null.
208	+	*
209	+	* <p><em>jsr166e note: During transition, this class
210	+	* uses nested functional interfaces with different names but the
211	+	* same forms as those expected for JDK8.</em>
212	+	*
213		* <p>This class is a member of the
214		* <a href="{@docRoot}/../technotes/guides/collections/index.html">
215		* Java Collections Framework</a>.
216		*
90	–	* <p><em>jsr166e note: This class is a candidate replacement for
91	–	* java.util.concurrent.ConcurrentHashMap.<em>
92	–	*
217		* @since 1.5
218		* @author Doug Lea
219		* @param <K> the type of keys maintained by this map
220		* @param <V> the type of mapped values
221		*/
222	<	public class ConcurrentHashMapV8<K, V>
223	<	implements ConcurrentMap<K, V>, Serializable {
222	>	public class ConcurrentHashMapV8<K,V> extends AbstractMap<K,V>
223	>	implements ConcurrentMap<K,V>, Serializable {
224		private static final long serialVersionUID = 7249069246763182397L;
225
226		/**
227	<	* A function computing a mapping from the given key to a value.
228	<	* This is a place-holder for an upcoming JDK8 interface.
227	>	* An object for traversing and partitioning elements of a source.
228	>	* This interface provides a subset of the functionality of JDK8
229	>	* java.util.Spliterator.
230		*/
231	<	public static interface MappingFunction<K, V> {
231	>	public static interface ConcurrentHashMapSpliterator<T> {
232		/**
233	<	* Returns a value for the given key, or null if there is no mapping.
234	<	*
235	<	* @param key the (non-null) key
236	<	* @return a value for the key, or null if none
233	>	* If possible, returns a new spliterator covering
234	>	* approximately one half of the elements, which will not be
235	>	* covered by this spliterator. Returns null if cannot be
236	>	* split.
237		*/
238	<	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> {
238	>	ConcurrentHashMapSpliterator<T> trySplit();
239		/**
240	<	* Returns a new value given a key and its current value.
241	<	*
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
240	>	* Returns an estimate of the number of elements covered by
241	>	* this Spliterator.
242		*/
243	<	Spliterator<T> split();
244	<	}
243	>	long estimateSize();
244	>
245	>	/** Applies the action to each untraversed element */
246	>	void forEachRemaining(Action<? super T> action);
247	>	/** If an element remains, applies the action and returns true. */
248	>	boolean tryAdvance(Action<? super T> action);
249	>	}
250	>
251	>	// Sams
252	>	/** Interface describing a void action of one argument */
253	>	public interface Action<A> { void apply(A a); }
254	>	/** Interface describing a void action of two arguments */
255	>	public interface BiAction<A,B> { void apply(A a, B b); }
256	>	/** Interface describing a function of one argument */
257	>	public interface Fun<A,T> { T apply(A a); }
258	>	/** Interface describing a function of two arguments */
259	>	public interface BiFun<A,B,T> { T apply(A a, B b); }
260	>	/** Interface describing a function mapping its argument to a double */
261	>	public interface ObjectToDouble<A> { double apply(A a); }
262	>	/** Interface describing a function mapping its argument to a long */
263	>	public interface ObjectToLong<A> { long apply(A a); }
264	>	/** Interface describing a function mapping its argument to an int */
265	>	public interface ObjectToInt<A> {int apply(A a); }
266	>	/** Interface describing a function mapping two arguments to a double */
267	>	public interface ObjectByObjectToDouble<A,B> { double apply(A a, B b); }
268	>	/** Interface describing a function mapping two arguments to a long */
269	>	public interface ObjectByObjectToLong<A,B> { long apply(A a, B b); }
270	>	/** Interface describing a function mapping two arguments to an int */
271	>	public interface ObjectByObjectToInt<A,B> {int apply(A a, B b); }
272	>	/** Interface describing a function mapping two doubles to a double */
273	>	public interface DoubleByDoubleToDouble { double apply(double a, double b); }
274	>	/** Interface describing a function mapping two longs to a long */
275	>	public interface LongByLongToLong { long apply(long a, long b); }
276	>	/** Interface describing a function mapping two ints to an int */
277	>	public interface IntByIntToInt { int apply(int a, int b); }
278	>
279
280		/*
281		* Overview:
#	Line 207 | Line 287 | public class ConcurrentHashMapV8<K, V>
287		* the same or better than java.util.HashMap, and to support high
288		* initial insertion rates on an empty table by many threads.
289		*
290	<	* Each key-value mapping is held in a Node.  Because Node fields
291	<	* can contain special values, they are defined using plain Object
292	<	* types. Similarly in turn, all internal methods that use them
293	<	* work off Object types. And similarly, so do the internal
294	<	* methods of auxiliary iterator and view classes.  All public
295	<	* generic typed methods relay in/out of these internal methods,
296	<	* supplying null-checks and casts as needed. This also allows
297	<	* many of the public methods to be factored into a smaller number
298	<	* of internal methods (although sadly not so for the five
299	<	* variants of put-related operations). The validation-based
300	<	* approach explained below leads to a lot of code sprawl because
301	<	* retry-control precludes factoring into smaller methods.
290	>	* This map usually acts as a binned (bucketed) hash table.  Each
291	>	* key-value mapping is held in a Node.  Most nodes are instances
292	>	* of the basic Node class with hash, key, value, and next
293	>	* fields. However, various subclasses exist: TreeNodes are
294	>	* arranged in balanced trees, not lists.  TreeBins hold the roots
295	>	* of sets of TreeNodes. ForwardingNodes are placed at the heads
296	>	* of bins during resizing. ReservationNodes are used as
297	>	* placeholders while establishing values in computeIfAbsent and
298	>	* related methods.  The types TreeBin, ForwardingNode, and
299	>	* ReservationNode do not hold normal user keys, values, or
300	>	* hashes, and are readily distinguishable during search etc
301	>	* because they have negative hash fields and null key and value
302	>	* fields. (These special nodes are either uncommon or transient,
303	>	* so the impact of carrying around some unused fields is
304	>	* insignificant.)
305		*
306		* The table is lazily initialized to a power-of-two size upon the
307		* first insertion.  Each bin in the table normally contains a
#	Line 226 | Line 309 | public class ConcurrentHashMapV8<K, V>
309		* Table accesses require volatile/atomic reads, writes, and
310		* CASes.  Because there is no other way to arrange this without
311		* adding further indirections, we use intrinsics
312	<	* (sun.misc.Unsafe) operations.  The lists of nodes within bins
313	<	* are always accurately traversable under volatile reads, so long
314	<	* as lookups check hash code and non-nullness of value before
315	<	* checking key equality.
316	<	*
317	<	* 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).
312	>	* (sun.misc.Unsafe) operations.
313	>	*
314	>	* We use the top (sign) bit of Node hash fields for control
315	>	* purposes -- it is available anyway because of addressing
316	>	* constraints.  Nodes with negative hash fields are specially
317	>	* handled or ignored in map methods.
318		*
319		* Insertion (via put or its variants) of the first node in an
320		* empty bin is performed by just CASing it to the bin.  This is
#	Line 252 | Line 323 | public class ConcurrentHashMapV8<K, V>
323		* delete, and replace) require locks.  We do not want to waste
324		* the space required to associate a distinct lock object with
325		* each bin, so instead use the first node of a bin list itself as
326	<	* a lock. Blocking support for these locks relies on the builtin
327	<	* "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.
326	>	* a lock. Locking support for these locks relies on builtin
327	>	* "synchronized" monitors.
328		*
329		* Using the first node of a list as a lock does not by itself
330		* suffice though: When a node is locked, any update must first
331		* validate that it is still the first node after locking it, and
332		* retry if not. Because new nodes are always appended to lists,
333		* once a node is first in a bin, it remains first until deleted
334	<	* 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.
334	>	* or the bin becomes invalidated (upon resizing).
335		*
336		* The main disadvantage of per-bin locks is that other update
337		* operations on other nodes in a bin list protected by the same
#	Line 300 | Line 364 | public class ConcurrentHashMapV8<K, V>
364		* sometimes deviate significantly from uniform randomness.  This
365		* includes the case when N > (1<<30), so some keys MUST collide.
366		* Similarly for dumb or hostile usages in which multiple keys are
367	<	* designed to have identical hash codes. Also, although we guard
368	<	* against the worst effects of this (see method spread), sets of
369	<	* hashes may differ only in bits that do not impact their bin
370	<	* index for a given power-of-two mask.  So we use a secondary
371	<	* strategy that applies when the number of nodes in a bin exceeds
372	<	* 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
367	>	* designed to have identical hash codes or ones that differs only
368	>	* in masked-out high bits. So we use a secondary strategy that
369	>	* applies when the number of nodes in a bin exceeds a
370	>	* threshold. These TreeBins use a balanced tree to hold nodes (a
371	>	* specialized form of red-black trees), bounding search time to
372	>	* O(log N).  Each search step in a TreeBin is at least twice as
373		* slow as in a regular list, but given that N cannot exceed
374		* (1<<64) (before running out of addresses) this bounds search
375		* steps, lock hold times, etc, to reasonable constants (roughly
#	Line 319 | Line 380 | public class ConcurrentHashMapV8<K, V>
380		* iterators in the same way.
381		*
382		* The table is resized when occupancy exceeds a percentage
383	<	* threshold (nominally, 0.75, but see below).  Only a single
384	<	* thread performs the resize (using field "sizeCtl", to arrange
385	<	* exclusion), but the table otherwise remains usable for reads
386	<	* and updates. Resizing proceeds by transferring bins, one by
387	<	* one, from the table to the next table.  Because we are using
388	<	* power-of-two expansion, the elements from each bin must either
389	<	* stay at same index, or move with a power of two offset. We
390	<	* eliminate unnecessary node creation by catching cases where old
391	<	* nodes can be reused because their next fields won't change.  On
392	<	* average, only about one-sixth of them need cloning when a table
393	<	* doubles. The nodes they replace will be garbage collectable as
394	<	* soon as they are no longer referenced by any reader thread that
395	<	* may be in the midst of concurrently traversing table.  Upon
396	<	* transfer, the old table bin contains only a special forwarding
397	<	* node (with hash field "MOVED") that contains the next table as
398	<	* its key. On encountering a forwarding node, access and update
399	<	* operations restart, using the new table.
400	<	*
401	<	* Each bin transfer requires its bin lock. However, unlike other
402	<	* cases, a transfer can skip a bin if it fails to acquire its
403	<	* lock, and revisit it later (unless it is a TreeBin). Method
404	<	* rebuild maintains a buffer of TRANSFER_BUFFER_SIZE bins that
405	<	* have been skipped because of failure to acquire a lock, and
406	<	* blocks only if none are available (i.e., only very rarely).
407	<	* The transfer operation must also ensure that all accessible
408	<	* bins in both the old and new table are usable by any traversal.
409	<	* When there are no lock acquisition failures, this is arranged
410	<	* simply by proceeding from the last bin (table.length - 1) up
411	<	* towards the first.  Upon seeing a forwarding node, traversals
412	<	* (see class InternalIterator) arrange to move to the new table
413	<	* without revisiting nodes.  However, when any node is skipped
414	<	* during a transfer, all earlier table bins may have become
415	<	* visible, so are initialized with a reverse-forwarding node back
416	<	* to the old table until the new ones are established. (This
417	<	* sometimes requires transiently locking a forwarding node, which
418	<	* is possible under the above encoding.) These more expensive
419	<	* mechanics trigger only when necessary.
383	>	* threshold (nominally, 0.75, but see below).  Any thread
384	>	* noticing an overfull bin may assist in resizing after the
385	>	* initiating thread allocates and sets up the replacement array.
386	>	* However, rather than stalling, these other threads may proceed
387	>	* with insertions etc.  The use of TreeBins shields us from the
388	>	* worst case effects of overfilling while resizes are in
389	>	* progress.  Resizing proceeds by transferring bins, one by one,
390	>	* from the table to the next table. However, threads claim small
391	>	* blocks of indices to transfer (via field transferIndex) before
392	>	* doing so, reducing contention.  A generation stamp in field
393	>	* sizeCtl ensures that resizings do not overlap. Because we are
394	>	* using power-of-two expansion, the elements from each bin must
395	>	* either stay at same index, or move with a power of two
396	>	* offset. We eliminate unnecessary node creation by catching
397	>	* cases where old nodes can be reused because their next fields
398	>	* won't change.  On average, only about one-sixth of them need
399	>	* cloning when a table doubles. The nodes they replace will be
400	>	* garbage collectable as soon as they are no longer referenced by
401	>	* any reader thread that may be in the midst of concurrently
402	>	* traversing table.  Upon transfer, the old table bin contains
403	>	* only a special forwarding node (with hash field "MOVED") that
404	>	* contains the next table as its key. On encountering a
405	>	* forwarding node, access and update operations restart, using
406	>	* the new table.
407	>	*
408	>	* Each bin transfer requires its bin lock, which can stall
409	>	* waiting for locks while resizing. However, because other
410	>	* threads can join in and help resize rather than contend for
411	>	* locks, average aggregate waits become shorter as resizing
412	>	* progresses.  The transfer operation must also ensure that all
413	>	* accessible bins in both the old and new table are usable by any
414	>	* traversal.  This is arranged in part by proceeding from the
415	>	* last bin (table.length - 1) up towards the first.  Upon seeing
416	>	* a forwarding node, traversals (see class Traverser) arrange to
417	>	* move to the new table without revisiting nodes.  To ensure that
418	>	* no intervening nodes are skipped even when moved out of order,
419	>	* a stack (see class TableStack) is created on first encounter of
420	>	* a forwarding node during a traversal, to maintain its place if
421	>	* later processing the current table. The need for these
422	>	* save/restore mechanics is relatively rare, but when one
423	>	* forwarding node is encountered, typically many more will be.
424	>	* So Traversers use a simple caching scheme to avoid creating so
425	>	* many new TableStack nodes. (Thanks to Peter Levart for
426	>	* suggesting use of a stack here.)
427		*
428		* The traversal scheme also applies to partial traversals of
429	<	* ranges of bins (via an alternate InternalIterator constructor)
429	>	* ranges of bins (via an alternate Traverser constructor)
430		* to support partitioned aggregate operations.  Also, read-only
431		* operations give up if ever forwarded to a null table, which
432		* provides support for shutdown-style clearing, which is also not
#	Line 370 | Line 438 | public class ConcurrentHashMapV8<K, V>
438		* These cases attempt to override the initial capacity settings,
439		* but harmlessly fail to take effect in cases of races.
440		*
441	<	* The element count is maintained using a LongAdder, which avoids
442	<	* contention on updates but can encounter cache thrashing if read
443	<	* too frequently during concurrent access. To avoid reading so
444	<	* often, resizing is attempted either when a bin lock is
445	<	* contended, or upon adding to a bin already holding two or more
446	<	* nodes (checked before adding in the xIfAbsent methods, after
447	<	* adding in others). Under uniform hash distributions, the
448	<	* probability of this occurring at threshold is around 13%,
449	<	* meaning that only about 1 in 8 puts check threshold (and after
450	<	* resizing, many fewer do so). But this approximation has high
451	<	* variance for small table sizes, so we check on any collision
452	<	* for sizes <= 64. The bulk putAll operation further reduces
453	<	* contention by only committing count updates upon these size
454	<	* checks.
441	>	* The element count is maintained using a specialization of
442	>	* LongAdder. We need to incorporate a specialization rather than
443	>	* just use a LongAdder in order to access implicit
444	>	* contention-sensing that leads to creation of multiple
445	>	* CounterCells.  The counter mechanics avoid contention on
446	>	* updates but can encounter cache thrashing if read too
447	>	* frequently during concurrent access. To avoid reading so often,
448	>	* resizing under contention is attempted only upon adding to a
449	>	* bin already holding two or more nodes. Under uniform hash
450	>	* distributions, the probability of this occurring at threshold
451	>	* is around 13%, meaning that only about 1 in 8 puts check
452	>	* threshold (and after resizing, many fewer do so).
453	>	*
454	>	* TreeBins use a special form of comparison for search and
455	>	* related operations (which is the main reason we cannot use
456	>	* existing collections such as TreeMaps). TreeBins contain
457	>	* Comparable elements, but may contain others, as well as
458	>	* elements that are Comparable but not necessarily Comparable for
459	>	* the same T, so we cannot invoke compareTo among them. To handle
460	>	* this, the tree is ordered primarily by hash value, then by
461	>	* Comparable.compareTo order if applicable.  On lookup at a node,
462	>	* if elements are not comparable or compare as 0 then both left
463	>	* and right children may need to be searched in the case of tied
464	>	* hash values. (This corresponds to the full list search that
465	>	* would be necessary if all elements were non-Comparable and had
466	>	* tied hashes.) On insertion, to keep a total ordering (or as
467	>	* close as is required here) across rebalancings, we compare
468	>	* classes and identityHashCodes as tie-breakers. The red-black
469	>	* balancing code is updated from pre-jdk-collections
470	>	* (http://gee.cs.oswego.edu/dl/classes/collections/RBCell.java)
471	>	* based in turn on Cormen, Leiserson, and Rivest "Introduction to
472	>	* Algorithms" (CLR).
473	>	*
474	>	* TreeBins also require an additional locking mechanism.  While
475	>	* list traversal is always possible by readers even during
476	>	* updates, tree traversal is not, mainly because of tree-rotations
477	>	* that may change the root node and/or its linkages.  TreeBins
478	>	* include a simple read-write lock mechanism parasitic on the
479	>	* main bin-synchronization strategy: Structural adjustments
480	>	* associated with an insertion or removal are already bin-locked
481	>	* (and so cannot conflict with other writers) but must wait for
482	>	* ongoing readers to finish. Since there can be only one such
483	>	* waiter, we use a simple scheme using a single "waiter" field to
484	>	* block writers.  However, readers need never block.  If the root
485	>	* lock is held, they proceed along the slow traversal path (via
486	>	* next-pointers) until the lock becomes available or the list is
487	>	* exhausted, whichever comes first. These cases are not fast, but
488	>	* maximize aggregate expected throughput.
489		*
490		* Maintaining API and serialization compatibility with previous
491		* versions of this class introduces several oddities. Mainly: We
#	Line 393 | Line 495 | public class ConcurrentHashMapV8<K, V>
495		* time that we can guarantee to honor it.) We also declare an
496		* unused "Segment" class that is instantiated in minimal form
497		* only when serializing.
498	+	*
499	+	* Also, solely for compatibility with previous versions of this
500	+	* class, it extends AbstractMap, even though all of its methods
501	+	* are overridden, so it is just useless baggage.
502	+	*
503	+	* This file is organized to make things a little easier to follow
504	+	* while reading than they might otherwise: First the main static
505	+	* declarations and utilities, then fields, then main public
506	+	* methods (with a few factorings of multiple public methods into
507	+	* internal ones), then sizing methods, trees, traversers, and
508	+	* bulk operations.
509		*/
510
511		/* ---------------- Constants -------------- */
#	Line 434 | Line 547 | public class ConcurrentHashMapV8<K, V>
547		private static final float LOAD_FACTOR = 0.75f;
548
549		/**
550	<	* The buffer size for skipped bins during transfers. The
551	<	* value is arbitrary but should be large enough to avoid
552	<	* most locking stalls during resizes.
550	>	* The bin count threshold for using a tree rather than list for a
551	>	* bin.  Bins are converted to trees when adding an element to a
552	>	* bin with at least this many nodes. The value must be greater
553	>	* than 2, and should be at least 8 to mesh with assumptions in
554	>	* tree removal about conversion back to plain bins upon
555	>	* shrinkage.
556		*/
557	<	private static final int TRANSFER_BUFFER_SIZE = 32;
557	>	static final int TREEIFY_THRESHOLD = 8;
558
559		/**
560	<	* The bin count threshold for using a tree rather than list for a
561	<	* bin.  The value reflects the approximate break-even point for
562	<	* using tree-based operations.
560	>	* The bin count threshold for untreeifying a (split) bin during a
561	>	* resize operation. Should be less than TREEIFY_THRESHOLD, and at
562	>	* most 6 to mesh with shrinkage detection under removal.
563		*/
564	<	private static final int TREE_THRESHOLD = 8;
564	>	static final int UNTREEIFY_THRESHOLD = 6;
565
566	<	/*
567	<	* Encodings for special uses of Node hash fields. See above for
568	<	* explanation.
566	>	/**
567	>	* The smallest table capacity for which bins may be treeified.
568	>	* (Otherwise the table is resized if too many nodes in a bin.)
569	>	* The value should be at least 4 * TREEIFY_THRESHOLD to avoid
570	>	* conflicts between resizing and treeification thresholds.
571		*/
572	<	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 -------------- */
572	>	static final int MIN_TREEIFY_CAPACITY = 64;
573
574		/**
575	<	* The array of bins. Lazily initialized upon first insertion.
576	<	* Size is always a power of two. Accessed directly by iterators.
575	>	* Minimum number of rebinnings per transfer step. Ranges are
576	>	* subdivided to allow multiple resizer threads.  This value
577	>	* serves as a lower bound to avoid resizers encountering
578	>	* excessive memory contention.  The value should be at least
579	>	* DEFAULT_CAPACITY.
580		*/
581	<	transient volatile Node[] table;
581	>	private static final int MIN_TRANSFER_STRIDE = 16;
582
583		/**
584	<	* The counter maintaining number of elements.
584	>	* The number of bits used for generation stamp in sizeCtl.
585	>	* Must be at least 6 for 32bit arrays.
586		*/
587	<	private transient final LongAdder counter;
587	>	private static int RESIZE_STAMP_BITS = 16;
588
589		/**
590	<	* Table initialization and resizing control.  When negative, the
591	<	* 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.
590	>	* The maximum number of threads that can help resize.
591	>	* Must fit in 32 - RESIZE_STAMP_BITS bits.
592		*/
593	<	private transient volatile int sizeCtl;
593	>	private static final int MAX_RESIZERS = (1 << (32 - RESIZE_STAMP_BITS)) - 1;
594
595	<	// views
596	<	private transient KeySet<K,V> keySet;
597	<	private transient Values<K,V> values;
598	<	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 -------------- */
595	>	/**
596	>	* The bit shift for recording size stamp in sizeCtl.
597	>	*/
598	>	private static final int RESIZE_STAMP_SHIFT = 32 - RESIZE_STAMP_BITS;
599
600		/*
601	<	* 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.
601	>	* Encodings for Node hash fields. See above for explanation.
602		*/
603	<
604	<	static final Node tabAt(Node[] tab, int i) { // used by InternalIterator
605	<	return (Node)UNSAFE.getObjectVolatile(tab, ((long)i<<ASHIFT)+ABASE);
606	<	}
607	<
608	<	private static final boolean casTabAt(Node[] tab, int i, Node c, Node v) {
609	<	return UNSAFE.compareAndSwapObject(tab, ((long)i<<ASHIFT)+ABASE, c, v);
610	<	}
611	<
612	<	private static final void setTabAt(Node[] tab, int i, Node v) {
613	<	UNSAFE.putObjectVolatile(tab, ((long)i<<ASHIFT)+ABASE, v);
614	<	}
603	>	static final int MOVED     = -1; // hash for forwarding nodes
604	>	static final int TREEBIN   = -2; // hash for roots of trees
605	>	static final int RESERVED  = -3; // hash for transient reservations
606	>	static final int HASH_BITS = 0x7fffffff; // usable bits of normal node hash
607	>
608	>	/** Number of CPUS, to place bounds on some sizings */
609	>	static final int NCPU = Runtime.getRuntime().availableProcessors();
610	>
611	>	/** For serialization compatibility. */
612	>	private static final ObjectStreamField[] serialPersistentFields = {
613	>	new ObjectStreamField("segments", Segment[].class),
614	>	new ObjectStreamField("segmentMask", Integer.TYPE),
615	>	new ObjectStreamField("segmentShift", Integer.TYPE)
616	>	};
617
618		/* ---------------- Nodes -------------- */
619
620		/**
621	<	* Key-value entry. Note that this is never exported out as a
622	<	* user-visible Map.Entry (see MapEntry below). Nodes with a hash
623	<	* field of MOVED are special, and do not contain user keys or
624	<	* values.  Otherwise, keys are never null, and null val fields
625	<	* indicate that a node is in the process of being deleted or
626	<	* created. For purposes of read-only access, a key may be read
627	<	* before a val, but can only be used after checking val to be
628	<	* non-null.
629	<	*/
630	<	static class Node {
631	<	volatile int hash;
632	<	final Object key;
530	<	volatile Object val;
531	<	volatile Node next;
621	>	* Key-value entry.  This class is never exported out as a
622	>	* user-mutable Map.Entry (i.e., one supporting setValue; see
623	>	* MapEntry below), but can be used for read-only traversals used
624	>	* in bulk tasks.  Subclasses of Node with a negative hash field
625	>	* are special, and contain null keys and values (but are never
626	>	* exported).  Otherwise, keys and vals are never null.
627	>	*/
628	>	static class Node<K,V> implements Map.Entry<K,V> {
629	>	final int hash;
630	>	final K key;
631	>	volatile V val;
632	>	volatile Node<K,V> next;
633
634	<	Node(int hash, Object key, Object val, Node next) {
634	>	Node(int hash, K key, V val, Node<K,V> next) {
635		this.hash = hash;
636		this.key = key;
637		this.val = val;
638		this.next = next;
639		}
640
641	<	/** CompareAndSet the hash field */
642	<	final boolean casHash(int cmp, int val) {
643	<	return UNSAFE.compareAndSwapInt(this, hashOffset, cmp, val);
644	<	}
645	<
646	<	/** 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;
641	>	public final K getKey()       { return key; }
642	>	public final V getValue()     { return val; }
643	>	public final int hashCode()   { return key.hashCode() ^ val.hashCode(); }
644	>	public final String toString(){ return key + "=" + val; }
645	>	public final V setValue(V value) {
646	>	throw new UnsupportedOperationException();
647		}
648
649	<	/**
650	<	* Wrapper for getTreeNode used by CHM.get. Tries to obtain
651	<	* read-lock to call getTreeNode, but during failure to get
652	<	* lock, searches along next links.
653	<	*/
654	<	final Object getValue(int h, Object k) {
655	<	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;
649	>	public final boolean equals(Object o) {
650	>	Object k, v, u; Map.Entry<?,?> e;
651	>	return ((o instanceof Map.Entry) &&
652	>	(k = (e = (Map.Entry<?,?>)o).getKey()) != null &&
653	>	(v = e.getValue()) != null &&
654	>	(k == key || k.equals(key)) &&
655	>	(v == (u = val) || v.equals(u)));
656		}
657
658		/**
659	<	* Finds or adds a node.
798	<	* @return null if added
659	>	* Virtualized support for map.get(); overridden in subclasses.
660		*/
661	<	@SuppressWarnings("unchecked") // suppress Comparable cast warning
662	<	final TreeNode putTreeNode(int h, Object k, Object v) {
663	<	Class<?> c = k.getClass();
664	<	TreeNode pp = root, p = null;
665	<	int dir = 0;
666	<	while (pp != null) { // find existing node or leaf to insert at
667	<	int ph;  Object pk; Class<?> pc;
668	<	p = pp;
669	<	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;
661	>	Node<K,V> find(int h, Object k) {
662	>	Node<K,V> e = this;
663	>	if (k != null) {
664	>	do {
665	>	K ek;
666	>	if (e.hash == h &&
667	>	((ek = e.key) == k || (ek != null && k.equals(ek))))
668	>	return e;
669	>	} while ((e = e.next) != null);
670		}
671		return null;
672		}
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	–	}
673		}
674
675	<	/* ---------------- Collision reduction methods -------------- */
675	>	/* ---------------- Static utilities -------------- */
676
677		/**
678	<	* Spreads higher bits to lower, and also forces top 2 bits to 0.
679	<	* Because the table uses power-of-two masking, sets of hashes
680	<	* that vary only in bits above the current mask will always
681	<	* collide. (Among known examples are sets of Float keys holding
682	<	* consecutive whole numbers in small tables.)  To counter this,
683	<	* we apply a transform that spreads the impact of higher bits
678	>	* Spreads (XORs) higher bits of hash to lower and also forces top
679	>	* bit to 0. Because the table uses power-of-two masking, sets of
680	>	* hashes that vary only in bits above the current mask will
681	>	* always collide. (Among known examples are sets of Float keys
682	>	* holding consecutive whole numbers in small tables.)  So we
683	>	* apply a transform that spreads the impact of higher bits
684		* downward. There is a tradeoff between speed, utility, and
685		* quality of bit-spreading. Because many common sets of hashes
686	<	* are already reasonably distributed across bits (so don't benefit
687	<	* from spreading), and because we use trees to handle large sets
688	<	* of collisions in bins, we don't need excessively high quality.
689	<	*/
690	<	private static final int spread(int h) {
691	<	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.
686	>	* are already reasonably distributed (so don't benefit from
687	>	* spreading), and because we use trees to handle large sets of
688	>	* collisions in bins, we just XOR some shifted bits in the
689	>	* cheapest possible way to reduce systematic lossage, as well as
690	>	* to incorporate impact of the highest bits that would otherwise
691	>	* never be used in index calculations because of table bounds.
692		*/
693	<	private final void replaceWithTreeBin(Node[] tab, int index, Object key) {
694	<	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();
693	>	static final int spread(int h) {
694	>	return (h ^ (h >>> 16)) & HASH_BITS;
695		}
696
1795	–	/* ---------------- Table Initialization and Resizing -------------- */
1796	–
697		/**
698		* Returns a power of two table size for the given desired capacity.
699		* See Hackers Delight, sec 3.2
#	Line 1809 | Line 709 | public class ConcurrentHashMapV8<K, V>
709		}
710
711		/**
712	<	* Initializes table, using the size recorded in sizeCtl.
712	>	* Returns x's Class if it is of the form "class C implements
713	>	* Comparable<C>", else null.
714		*/
715	<	private final Node[] initTable() {
716	<	Node[] tab; int sc;
717	<	while ((tab = table) == null) {
718	<	if ((sc = sizeCtl) < 0)
719	<	Thread.yield(); // lost initialization race; just spin
720	<	else if (UNSAFE.compareAndSwapInt(this, sizeCtlOffset, sc, -1)) {
721	<	try {
722	<	if ((tab = table) == null) {
723	<	int n = (sc > 0) ? sc : DEFAULT_CAPACITY;
724	<	tab = table = new Node[n];
725	<	sc = n - (n >>> 2);
726	<	}
727	<	} finally {
1827	<	sizeCtl = sc;
715	>	static Class<?> comparableClassFor(Object x) {
716	>	if (x instanceof Comparable) {
717	>	Class<?> c; Type[] ts, as; Type t; ParameterizedType p;
718	>	if ((c = x.getClass()) == String.class) // bypass checks
719	>	return c;
720	>	if ((ts = c.getGenericInterfaces()) != null) {
721	>	for (int i = 0; i < ts.length; ++i) {
722	>	if (((t = ts[i]) instanceof ParameterizedType) &&
723	>	((p = (ParameterizedType)t).getRawType() ==
724	>	Comparable.class) &&
725	>	(as = p.getActualTypeArguments()) != null &&
726	>	as.length == 1 && as[0] == c) // type arg is c
727	>	return c;
728		}
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;
729		}
730		}
731	+	return null;
732		}
733
734		/**
735	<	* Tries to presize table to accommodate the given number of elements.
736	<	*
1861	<	* @param size number of elements (doesn't need to be perfectly accurate)
735	>	* Returns k.compareTo(x) if x matches kc (k's screened comparable
736	>	* class), else 0.
737		*/
738	<	private final void tryPresize(int size) {
739	<	int c = (size >= (MAXIMUM_CAPACITY >>> 1)) ? MAXIMUM_CAPACITY :
740	<	tableSizeFor(size + (size >>> 1) + 1);
741	<	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	<	}
738	>	@SuppressWarnings({"rawtypes","unchecked"}) // for cast to Comparable
739	>	static int compareComparables(Class<?> kc, Object k, Object x) {
740	>	return (x == null || x.getClass() != kc ? 0 :
741	>	((Comparable)k).compareTo(x));
742		}
743
744	+	/* ---------------- Table element access -------------- */
745	+
746		/*
747	<	* Moves and/or copies the nodes in each bin to new table. See
748	<	* above for explanation.
749	<	*
750	<	* @return the new table
747	>	* Volatile access methods are used for table elements as well as
748	>	* elements of in-progress next table while resizing.  All uses of
749	>	* the tab arguments must be null checked by callers.  All callers
750	>	* also paranoically precheck that tab's length is not zero (or an
751	>	* equivalent check), thus ensuring that any index argument taking
752	>	* the form of a hash value anded with (length - 1) is a valid
753	>	* index.  Note that, to be correct wrt arbitrary concurrency
754	>	* errors by users, these checks must operate on local variables,
755	>	* which accounts for some odd-looking inline assignments below.
756	>	* Note that calls to setTabAt always occur within locked regions,
757	>	* and so in principle require only release ordering, not
758	>	* full volatile semantics, but are currently coded as volatile
759	>	* writes to be conservative.
760		*/
761	<	private static final Node[] rebuild(Node[] tab) {
762	<	int n = tab.length;
763	<	Node[] nextTab = new Node[n << 1];
764	<	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	<	}
761	>
762	>	@SuppressWarnings("unchecked")
763	>	static final <K,V> Node<K,V> tabAt(Node<K,V>[] tab, int i) {
764	>	return (Node<K,V>)U.getObjectVolatile(tab, ((long)i << ASHIFT) + ABASE);
765		}
766
767	+	static final <K,V> boolean casTabAt(Node<K,V>[] tab, int i,
768	+	Node<K,V> c, Node<K,V> v) {
769	+	return U.compareAndSwapObject(tab, ((long)i << ASHIFT) + ABASE, c, v);
770	+	}
771	+
772	+	static final <K,V> void setTabAt(Node<K,V>[] tab, int i, Node<K,V> v) {
773	+	U.putObjectVolatile(tab, ((long)i << ASHIFT) + ABASE, v);
774	+	}
775	+
776	+	/* ---------------- Fields -------------- */
777	+
778		/**
779	<	* Splits a normal bin with list headed by e into lo and hi parts;
780	<	* installs in given table.
779	>	* The array of bins. Lazily initialized upon first insertion.
780	>	* Size is always a power of two. Accessed directly by iterators.
781		*/
782	<	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	<	}
782	>	transient volatile Node<K,V>[] table;
783
784		/**
785	<	* Splits a tree bin into lo and hi parts; installs in given table.
785	>	* The next table to use; non-null only while resizing.
786		*/
787	<	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	<	}
787	>	private transient volatile Node<K,V>[] nextTable;
788
789		/**
790	<	* Implementation for clear. Steps through each bin, removing all
791	<	* nodes.
790	>	* Base counter value, used mainly when there is no contention,
791	>	* but also as a fallback during table initialization
792	>	* races. Updated via CAS.
793		*/
794	<	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	<	}
794	>	private transient volatile long baseCount;
795
796	<	/* ----------------Table Traversal -------------- */
796	>	/**
797	>	* Table initialization and resizing control.  When negative, the
798	>	* table is being initialized or resized: -1 for initialization,
799	>	* else -(1 + the number of active resizing threads).  Otherwise,
800	>	* when table is null, holds the initial table size to use upon
801	>	* creation, or 0 for default. After initialization, holds the
802	>	* next element count value upon which to resize the table.
803	>	*/
804	>	private transient volatile int sizeCtl;
805
806		/**
807	<	* 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.
807	>	* The next table index (plus one) to split while resizing.
808		*/
809	<	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	<	}
809	>	private transient volatile int transferIndex;
810
811	<	/**
812	<	* Advances next; returns nextVal or null if terminated.
813	<	* See above for explanation.
814	<	*/
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	<	}
811	>	/**
812	>	* Spinlock (locked via CAS) used when resizing and/or creating CounterCells.
813	>	*/
814	>	private transient volatile int cellsBusy;
815
816	<	public final void remove() {
817	<	if (nextVal == null)
818	<	advance();
819	<	Node e = last;
2236	<	if (e == null)
2237	<	throw new IllegalStateException();
2238	<	last = null;
2239	<	map.remove(e.key);
2240	<	}
816	>	/**
817	>	* Table of counter cells. When non-null, size is a power of 2.
818	>	*/
819	>	private transient volatile CounterCell[] counterCells;
820
821	<	public final boolean hasNext() {
822	<	return nextVal != null || advance() != null;
823	<	}
821	>	// views
822	>	private transient KeySetView<K,V> keySet;
823	>	private transient ValuesView<K,V> values;
824	>	private transient EntrySetView<K,V> entrySet;
825
2246	–	public final boolean hasMoreElements() { return hasNext(); }
2247	–	}
826
827		/* ---------------- Public operations -------------- */
828
#	Line 2252 | Line 830 | public class ConcurrentHashMapV8<K, V>
830		* Creates a new, empty map with the default initial table size (16).
831		*/
832		public ConcurrentHashMapV8() {
2255	–	this.counter = new LongAdder();
833		}
834
835		/**
#	Line 2271 | Line 848 | public class ConcurrentHashMapV8<K, V>
848		int cap = ((initialCapacity >= (MAXIMUM_CAPACITY >>> 1)) ?
849		MAXIMUM_CAPACITY :
850		tableSizeFor(initialCapacity + (initialCapacity >>> 1) + 1));
2274	–	this.counter = new LongAdder();
851		this.sizeCtl = cap;
852		}
853
#	Line 2281 | Line 857 | public class ConcurrentHashMapV8<K, V>
857		* @param m the map
858		*/
859		public ConcurrentHashMapV8(Map<? extends K, ? extends V> m) {
2284	–	this.counter = new LongAdder();
860		this.sizeCtl = DEFAULT_CAPACITY;
861	<	internalPutAll(m);
861	>	putAll(m);
862		}
863
864		/**
#	Line 2324 | Line 899 | public class ConcurrentHashMapV8<K, V>
899		* nonpositive
900		*/
901		public ConcurrentHashMapV8(int initialCapacity,
902	<	float loadFactor, int concurrencyLevel) {
902	>	float loadFactor, int concurrencyLevel) {
903		if (!(loadFactor > 0.0f) || initialCapacity < 0 || concurrencyLevel <= 0)
904		throw new IllegalArgumentException();
905		if (initialCapacity < concurrencyLevel)   // Use at least as many bins
#	Line 2332 | Line 907 | public class ConcurrentHashMapV8<K, V>
907		long size = (long)(1.0 + (long)initialCapacity / loadFactor);
908		int cap = (size >= (long)MAXIMUM_CAPACITY) ?
909		MAXIMUM_CAPACITY : tableSizeFor((int)size);
2335	–	this.counter = new LongAdder();
910		this.sizeCtl = cap;
911		}
912
913	<	/**
2340	<	* {@inheritDoc}
2341	<	*/
2342	<	public boolean isEmpty() {
2343	<	return counter.sum() <= 0L; // ignore transient negative values
2344	<	}
913	>	// Original (since JDK1.2) Map methods
914
915		/**
916		* {@inheritDoc}
917		*/
918		public int size() {
919	<	long n = counter.sum();
919	>	long n = sumCount();
920		return ((n < 0L) ? 0 :
921		(n > (long)Integer.MAX_VALUE) ? Integer.MAX_VALUE :
922		(int)n);
923		}
924
925	<	final long longSize() { // accurate version of size needed for views
926	<	long n = counter.sum();
927	<	return (n < 0L) ? 0L : n;
925	>	/**
926	>	* {@inheritDoc}
927	>	*/
928	>	public boolean isEmpty() {
929	>	return sumCount() <= 0L; // ignore transient negative values
930		}
931
932		/**
#	Line 2369 | Line 940 | public class ConcurrentHashMapV8<K, V>
940		*
941		* @throws NullPointerException if the specified key is null
942		*/
2372	–	@SuppressWarnings("unchecked")
943		public V get(Object key) {
944	<	if (key == null)
945	<	throw new NullPointerException();
946	<	return (V)internalGet(key);
944	>	Node<K,V>[] tab; Node<K,V> e, p; int n, eh; K ek;
945	>	int h = spread(key.hashCode());
946	>	if ((tab = table) != null && (n = tab.length) > 0 &&
947	>	(e = tabAt(tab, (n - 1) & h)) != null) {
948	>	if ((eh = e.hash) == h) {
949	>	if ((ek = e.key) == key || (ek != null && key.equals(ek)))
950	>	return e.val;
951	>	}
952	>	else if (eh < 0)
953	>	return (p = e.find(h, key)) != null ? p.val : null;
954	>	while ((e = e.next) != null) {
955	>	if (e.hash == h &&
956	>	((ek = e.key) == key || (ek != null && key.equals(ek))))
957	>	return e.val;
958	>	}
959	>	}
960	>	return null;
961		}
962
963		/**
964		* Tests if the specified object is a key in this table.
965		*
966	<	* @param  key   possible key
966	>	* @param  key possible key
967		* @return {@code true} if and only if the specified object
968		*         is a key in this table, as determined by the
969		*         {@code equals} method; {@code false} otherwise
970		* @throws NullPointerException if the specified key is null
971		*/
972		public boolean containsKey(Object key) {
973	<	if (key == null)
2390	<	throw new NullPointerException();
2391	<	return internalGet(key) != null;
973	>	return get(key) != null;
974		}
975
976		/**
#	Line 2404 | Line 986 | public class ConcurrentHashMapV8<K, V>
986		public boolean containsValue(Object value) {
987		if (value == null)
988		throw new NullPointerException();
989	<	Object v;
990	<	InternalIterator<K,V> it = new InternalIterator<K,V>(this);
991	<	while ((v = it.advance()) != null) {
992	<	if (v == value || value.equals(v))
993	<	return true;
989	>	Node<K,V>[] t;
990	>	if ((t = table) != null) {
991	>	Traverser<K,V> it = new Traverser<K,V>(t, t.length, 0, t.length);
992	>	for (Node<K,V> p; (p = it.advance()) != null; ) {
993	>	V v;
994	>	if ((v = p.val) == value || (v != null && value.equals(v)))
995	>	return true;
996	>	}
997		}
998		return false;
999		}
1000
1001		/**
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	–	/**
1002		* Maps the specified key to the specified value in this table.
1003		* Neither the key nor the value can be null.
1004		*
1005	<	* <p> The value can be retrieved by calling the {@code get} method
1005	>	* <p>The value can be retrieved by calling the {@code get} method
1006		* with a key that is equal to the original key.
1007		*
1008		* @param key key with which the specified value is to be associated
#	Line 2445 | Line 1011 | public class ConcurrentHashMapV8<K, V>
1011		*         {@code null} if there was no mapping for {@code key}
1012		* @throws NullPointerException if the specified key or value is null
1013		*/
2448	–	@SuppressWarnings("unchecked")
1014		public V put(K key, V value) {
1015	<	if (key == null || value == null)
2451	<	throw new NullPointerException();
2452	<	return (V)internalPut(key, value);
1015	>	return putVal(key, value, false);
1016		}
1017
1018	<	/**
1019	<	* {@inheritDoc}
1020	<	*
1021	<	* @return the previous value associated with the specified key,
1022	<	*         or {@code null} if there was no mapping for the key
1023	<	* @throws NullPointerException if the specified key or value is null
1024	<	*/
1025	<	@SuppressWarnings("unchecked")
1026	<	public V putIfAbsent(K key, V value) {
1027	<	if (key == null || value == null)
1028	<	throw new NullPointerException();
1029	<	return (V)internalPutIfAbsent(key, value);
1018	>	/** Implementation for put and putIfAbsent */
1019	>	final V putVal(K key, V value, boolean onlyIfAbsent) {
1020	>	if (key == null || value == null) throw new NullPointerException();
1021	>	int hash = spread(key.hashCode());
1022	>	int binCount = 0;
1023	>	for (Node<K,V>[] tab = table;;) {
1024	>	Node<K,V> f; int n, i, fh;
1025	>	if (tab == null || (n = tab.length) == 0)
1026	>	tab = initTable();
1027	>	else if ((f = tabAt(tab, i = (n - 1) & hash)) == null) {
1028	>	if (casTabAt(tab, i, null,
1029	>	new Node<K,V>(hash, key, value, null)))
1030	>	break;                   // no lock when adding to empty bin
1031	>	}
1032	>	else if ((fh = f.hash) == MOVED)
1033	>	tab = helpTransfer(tab, f);
1034	>	else {
1035	>	V oldVal = null;
1036	>	synchronized (f) {
1037	>	if (tabAt(tab, i) == f) {
1038	>	if (fh >= 0) {
1039	>	binCount = 1;
1040	>	for (Node<K,V> e = f;; ++binCount) {
1041	>	K ek;
1042	>	if (e.hash == hash &&
1043	>	((ek = e.key) == key ||
1044	>	(ek != null && key.equals(ek)))) {
1045	>	oldVal = e.val;
1046	>	if (!onlyIfAbsent)
1047	>	e.val = value;
1048	>	break;
1049	>	}
1050	>	Node<K,V> pred = e;
1051	>	if ((e = e.next) == null) {
1052	>	pred.next = new Node<K,V>(hash, key,
1053	>	value, null);
1054	>	break;
1055	>	}
1056	>	}
1057	>	}
1058	>	else if (f instanceof TreeBin) {
1059	>	Node<K,V> p;
1060	>	binCount = 2;
1061	>	if ((p = ((TreeBin<K,V>)f).putTreeVal(hash, key,
1062	>	value)) != null) {
1063	>	oldVal = p.val;
1064	>	if (!onlyIfAbsent)
1065	>	p.val = value;
1066	>	}
1067	>	}
1068	>	}
1069	>	}
1070	>	if (binCount != 0) {
1071	>	if (binCount >= TREEIFY_THRESHOLD)
1072	>	treeifyBin(tab, i);
1073	>	if (oldVal != null)
1074	>	return oldVal;
1075	>	break;
1076	>	}
1077	>	}
1078	>	}
1079	>	addCount(1L, binCount);
1080	>	return null;
1081		}
1082
1083		/**
#	Line 2474 | Line 1088 | public class ConcurrentHashMapV8<K, V>
1088		* @param m mappings to be stored in this map
1089		*/
1090		public void putAll(Map<? extends K, ? extends V> m) {
1091	<	internalPutAll(m);
1092	<	}
1093	<
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);
1091	>	tryPresize(m.size());
1092	>	for (Map.Entry<? extends K, ? extends V> e : m.entrySet())
1093	>	putVal(e.getKey(), e.getValue(), false);
1094		}
1095
1096		/**
#	Line 2580 | Line 1102 | public class ConcurrentHashMapV8<K, V>
1102		*         {@code null} if there was no mapping for {@code key}
1103		* @throws NullPointerException if the specified key is null
1104		*/
2583	–	@SuppressWarnings("unchecked")
1105		public V remove(Object key) {
1106	<	if (key == null)
2586	<	throw new NullPointerException();
2587	<	return (V)internalReplace(key, null, null);
1106	>	return replaceNode(key, null, null);
1107		}
1108
1109		/**
1110	<	* {@inheritDoc}
1111	<	*
1112	<	* @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
1110	>	* Implementation for the four public remove/replace methods:
1111	>	* Replaces node value with v, conditional upon match of cv if
1112	>	* non-null.  If resulting value is null, delete.
1113		*/
1114	<	@SuppressWarnings("unchecked")
1115	<	public V replace(K key, V value) {
1116	<	if (key == null || value == null)
1117	<	throw new NullPointerException();
1118	<	return (V)internalReplace(key, value, null);
1114	>	final V replaceNode(Object key, V value, Object cv) {
1115	>	int hash = spread(key.hashCode());
1116	>	for (Node<K,V>[] tab = table;;) {
1117	>	Node<K,V> f; int n, i, fh;
1118	>	if (tab == null || (n = tab.length) == 0 ||
1119	>	(f = tabAt(tab, i = (n - 1) & hash)) == null)
1120	>	break;
1121	>	else if ((fh = f.hash) == MOVED)
1122	>	tab = helpTransfer(tab, f);
1123	>	else {
1124	>	V oldVal = null;
1125	>	boolean validated = false;
1126	>	synchronized (f) {
1127	>	if (tabAt(tab, i) == f) {
1128	>	if (fh >= 0) {
1129	>	validated = true;
1130	>	for (Node<K,V> e = f, pred = null;;) {
1131	>	K ek;
1132	>	if (e.hash == hash &&
1133	>	((ek = e.key) == key ||
1134	>	(ek != null && key.equals(ek)))) {
1135	>	V ev = e.val;
1136	>	if (cv == null || cv == ev ||
1137	>	(ev != null && cv.equals(ev))) {
1138	>	oldVal = ev;
1139	>	if (value != null)
1140	>	e.val = value;
1141	>	else if (pred != null)
1142	>	pred.next = e.next;
1143	>	else
1144	>	setTabAt(tab, i, e.next);
1145	>	}
1146	>	break;
1147	>	}
1148	>	pred = e;
1149	>	if ((e = e.next) == null)
1150	>	break;
1151	>	}
1152	>	}
1153	>	else if (f instanceof TreeBin) {
1154	>	validated = true;
1155	>	TreeBin<K,V> t = (TreeBin<K,V>)f;
1156	>	TreeNode<K,V> r, p;
1157	>	if ((r = t.root) != null &&
1158	>	(p = r.findTreeNode(hash, key, null)) != null) {
1159	>	V pv = p.val;
1160	>	if (cv == null || cv == pv ||
1161	>	(pv != null && cv.equals(pv))) {
1162	>	oldVal = pv;
1163	>	if (value != null)
1164	>	p.val = value;
1165	>	else if (t.removeTreeNode(p))
1166	>	setTabAt(tab, i, untreeify(t.first));
1167	>	}
1168	>	}
1169	>	}
1170	>	}
1171	>	}
1172	>	if (validated) {
1173	>	if (oldVal != null) {
1174	>	if (value == null)
1175	>	addCount(-1L, -1);
1176	>	return oldVal;
1177	>	}
1178	>	break;
1179	>	}
1180	>	}
1181	>	}
1182	>	return null;
1183		}
1184
1185		/**
1186		* Removes all of the mappings from this map.
1187		*/
1188		public void clear() {
1189	<	internalClear();
1189	>	long delta = 0L; // negative number of deletions
1190	>	int i = 0;
1191	>	Node<K,V>[] tab = table;
1192	>	while (tab != null && i < tab.length) {
1193	>	int fh;
1194	>	Node<K,V> f = tabAt(tab, i);
1195	>	if (f == null)
1196	>	++i;
1197	>	else if ((fh = f.hash) == MOVED) {
1198	>	tab = helpTransfer(tab, f);
1199	>	i = 0; // restart
1200	>	}
1201	>	else {
1202	>	synchronized (f) {
1203	>	if (tabAt(tab, i) == f) {
1204	>	Node<K,V> p = (fh >= 0 ? f :
1205	>	(f instanceof TreeBin) ?
1206	>	((TreeBin<K,V>)f).first : null);
1207	>	while (p != null) {
1208	>	--delta;
1209	>	p = p.next;
1210	>	}
1211	>	setTabAt(tab, i++, null);
1212	>	}
1213	>	}
1214	>	}
1215	>	}
1216	>	if (delta != 0L)
1217	>	addCount(delta, -1);
1218		}
1219
1220		/**
1221		* Returns a {@link Set} view of the keys contained in this map.
1222		* The set is backed by the map, so changes to the map are
1223	<	* reflected in the set, and vice-versa.  The set supports element
1223	>	* reflected in the set, and vice-versa. The set supports element
1224		* removal, which removes the corresponding mapping from this map,
1225		* via the {@code Iterator.remove}, {@code Set.remove},
1226		* {@code removeAll}, {@code retainAll}, and {@code clear}
#	Line 2647 | Line 1232 | public class ConcurrentHashMapV8<K, V>
1232		* and guarantees to traverse elements as they existed upon
1233		* construction of the iterator, and may (but is not guaranteed to)
1234		* reflect any modifications subsequent to construction.
1235	+	*
1236	+	* @return the set view
1237		*/
1238	<	public Set<K> keySet() {
1239	<	KeySet<K,V> ks = keySet;
1240	<	return (ks != null) ? ks : (keySet = new KeySet<K,V>(this));
1238	>	public KeySetView<K,V> keySet() {
1239	>	KeySetView<K,V> ks;
1240	>	return (ks = keySet) != null ? ks : (keySet = new KeySetView<K,V>(this, null));
1241		}
1242
1243		/**
#	Line 2668 | Line 1255 | public class ConcurrentHashMapV8<K, V>
1255		* and guarantees to traverse elements as they existed upon
1256		* construction of the iterator, and may (but is not guaranteed to)
1257		* reflect any modifications subsequent to construction.
1258	+	*
1259	+	* @return the collection view
1260		*/
1261		public Collection<V> values() {
1262	<	Values<K,V> vs = values;
1263	<	return (vs != null) ? vs : (values = new Values<K,V>(this));
1262	>	ValuesView<K,V> vs;
1263	>	return (vs = values) != null ? vs : (values = new ValuesView<K,V>(this));
1264		}
1265
1266		/**
#	Line 2681 | Line 1270 | public class ConcurrentHashMapV8<K, V>
1270		* removal, which removes the corresponding mapping from the map,
1271		* via the {@code Iterator.remove}, {@code Set.remove},
1272		* {@code removeAll}, {@code retainAll}, and {@code clear}
1273	<	* operations.  It does not support the {@code add} or
2685	<	* {@code addAll} operations.
1273	>	* operations.
1274		*
1275		* <p>The view's {@code iterator} is a "weakly consistent" iterator
1276		* that will never throw {@link ConcurrentModificationException},
1277		* and guarantees to traverse elements as they existed upon
1278		* construction of the iterator, and may (but is not guaranteed to)
1279		* 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.
1280		*
1281	<	* @return an enumeration of the keys in this table
2702	<	* @see #keySet()
1281	>	* @return the set view
1282		*/
1283	<	public Enumeration<K> keys() {
1284	<	return new KeyIterator<K,V>(this);
1285	<	}
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.
2729	<	*
2730	<	* @return a partionable iterator of the values in this map
2731	<	*/
2732	<	public Spliterator<V> valueSpliterator() {
2733	<	return new ValueIterator<K,V>(this);
2734	<	}
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);
1283	>	public Set<Map.Entry<K,V>> entrySet() {
1284	>	EntrySetView<K,V> es;
1285	>	return (es = entrySet) != null ? es : (entrySet = new EntrySetView<K,V>(this));
1286		}
1287
1288		/**
#	Line 2751 | Line 1294 | public class ConcurrentHashMapV8<K, V>
1294		*/
1295		public int hashCode() {
1296		int h = 0;
1297	<	InternalIterator<K,V> it = new InternalIterator<K,V>(this);
1298	<	Object v;
1299	<	while ((v = it.advance()) != null) {
1300	<	h += it.nextKey.hashCode() ^ v.hashCode();
1297	>	Node<K,V>[] t;
1298	>	if ((t = table) != null) {
1299	>	Traverser<K,V> it = new Traverser<K,V>(t, t.length, 0, t.length);
1300	>	for (Node<K,V> p; (p = it.advance()) != null; )
1301	>	h += p.key.hashCode() ^ p.val.hashCode();
1302		}
1303		return h;
1304		}
#	Line 2771 | Line 1315 | public class ConcurrentHashMapV8<K, V>
1315		* @return a string representation of this map
1316		*/
1317		public String toString() {
1318	<	InternalIterator<K,V> it = new InternalIterator<K,V>(this);
1318	>	Node<K,V>[] t;
1319	>	int f = (t = table) == null ? 0 : t.length;
1320	>	Traverser<K,V> it = new Traverser<K,V>(t, f, 0, f);
1321		StringBuilder sb = new StringBuilder();
1322		sb.append('{');
1323	<	Object v;
1324	<	if ((v = it.advance()) != null) {
1323	>	Node<K,V> p;
1324	>	if ((p = it.advance()) != null) {
1325		for (;;) {
1326	<	Object k = it.nextKey;
1326	>	K k = p.key;
1327	>	V v = p.val;
1328		sb.append(k == this ? "(this Map)" : k);
1329		sb.append('=');
1330		sb.append(v == this ? "(this Map)" : v);
1331	<	if ((v = it.advance()) == null)
1331	>	if ((p = it.advance()) == null)
1332		break;
1333		sb.append(',').append(' ');
1334		}
#	Line 2804 | Line 1351 | public class ConcurrentHashMapV8<K, V>
1351		if (!(o instanceof Map))
1352		return false;
1353		Map<?,?> m = (Map<?,?>) o;
1354	<	InternalIterator<K,V> it = new InternalIterator<K,V>(this);
1355	<	Object val;
1356	<	while ((val = it.advance()) != null) {
1357	<	Object v = m.get(it.nextKey);
1354	>	Node<K,V>[] t;
1355	>	int f = (t = table) == null ? 0 : t.length;
1356	>	Traverser<K,V> it = new Traverser<K,V>(t, f, 0, f);
1357	>	for (Node<K,V> p; (p = it.advance()) != null; ) {
1358	>	V val = p.val;
1359	>	Object v = m.get(p.key);
1360		if (v == null || (v != val && !v.equals(val)))
1361		return false;
1362		}
#	Line 2815 | Line 1364 | public class ConcurrentHashMapV8<K, V>
1364		Object mk, mv, v;
1365		if ((mk = e.getKey()) == null ||
1366		(mv = e.getValue()) == null ||
1367	<	(v = internalGet(mk)) == null ||
1367	>	(v = get(mk)) == null ||
1368		(mv != v && !mv.equals(v)))
1369		return false;
1370		}
#	Line 2823 | Line 1372 | public class ConcurrentHashMapV8<K, V>
1372		return true;
1373		}
1374
1375	<	/* ----------------Iterators -------------- */
1375	>	/**
1376	>	* Stripped-down version of helper class used in previous version,
1377	>	* declared for the sake of serialization compatibility
1378	>	*/
1379	>	static class Segment<K,V> extends ReentrantLock implements Serializable {
1380	>	private static final long serialVersionUID = 2249069246763182397L;
1381	>	final float loadFactor;
1382	>	Segment(float lf) { this.loadFactor = lf; }
1383	>	}
1384
1385	<	static final class KeyIterator<K,V> extends InternalIterator<K,V>
1386	<	implements Spliterator<K>, Enumeration<K> {
1387	<	KeyIterator(ConcurrentHashMapV8<K, V> map) { super(map); }
1388	<	KeyIterator(InternalIterator<K,V> it, boolean split) {
1389	<	super(it, split);
1385	>	/**
1386	>	* Saves the state of the {@code ConcurrentHashMapV8} instance to a
1387	>	* stream (i.e., serializes it).
1388	>	* @param s the stream
1389	>	* @throws java.io.IOException if an I/O error occurs
1390	>	* @serialData
1391	>	* the key (Object) and value (Object)
1392	>	* for each key-value mapping, followed by a null pair.
1393	>	* The key-value mappings are emitted in no particular order.
1394	>	*/
1395	>	private void writeObject(java.io.ObjectOutputStream s)
1396	>	throws java.io.IOException {
1397	>	// For serialization compatibility
1398	>	// Emulate segment calculation from previous version of this class
1399	>	int sshift = 0;
1400	>	int ssize = 1;
1401	>	while (ssize < DEFAULT_CONCURRENCY_LEVEL) {
1402	>	++sshift;
1403	>	ssize <<= 1;
1404	>	}
1405	>	int segmentShift = 32 - sshift;
1406	>	int segmentMask = ssize - 1;
1407	>	@SuppressWarnings("unchecked") Segment<K,V>[] segments = (Segment<K,V>[])
1408	>	new Segment<?,?>[DEFAULT_CONCURRENCY_LEVEL];
1409	>	for (int i = 0; i < segments.length; ++i)
1410	>	segments[i] = new Segment<K,V>(LOAD_FACTOR);
1411	>	s.putFields().put("segments", segments);
1412	>	s.putFields().put("segmentShift", segmentShift);
1413	>	s.putFields().put("segmentMask", segmentMask);
1414	>	s.writeFields();
1415	>
1416	>	Node<K,V>[] t;
1417	>	if ((t = table) != null) {
1418	>	Traverser<K,V> it = new Traverser<K,V>(t, t.length, 0, t.length);
1419	>	for (Node<K,V> p; (p = it.advance()) != null; ) {
1420	>	s.writeObject(p.key);
1421	>	s.writeObject(p.val);
1422	>	}
1423		}
1424	<	public KeyIterator<K,V> split() {
1425	<	if (last != null || (next != null && nextVal == null))
1426	<	throw new IllegalStateException();
1427	<	return new KeyIterator<K,V>(this, true);
1424	>	s.writeObject(null);
1425	>	s.writeObject(null);
1426	>	segments = null; // throw away
1427	>	}
1428	>
1429	>	/**
1430	>	* Reconstitutes the instance from a stream (that is, deserializes it).
1431	>	* @param s the stream
1432	>	* @throws ClassNotFoundException if the class of a serialized object
1433	>	*         could not be found
1434	>	* @throws java.io.IOException if an I/O error occurs
1435	>	*/
1436	>	private void readObject(java.io.ObjectInputStream s)
1437	>	throws java.io.IOException, ClassNotFoundException {
1438	>	/*
1439	>	* To improve performance in typical cases, we create nodes
1440	>	* while reading, then place in table once size is known.
1441	>	* However, we must also validate uniqueness and deal with
1442	>	* overpopulated bins while doing so, which requires
1443	>	* specialized versions of putVal mechanics.
1444	>	*/
1445	>	sizeCtl = -1; // force exclusion for table construction
1446	>	s.defaultReadObject();
1447	>	long size = 0L;
1448	>	Node<K,V> p = null;
1449	>	for (;;) {
1450	>	@SuppressWarnings("unchecked") K k = (K) s.readObject();
1451	>	@SuppressWarnings("unchecked") V v = (V) s.readObject();
1452	>	if (k != null && v != null) {
1453	>	p = new Node<K,V>(spread(k.hashCode()), k, v, p);
1454	>	++size;
1455	>	}
1456	>	else
1457	>	break;
1458		}
1459	<	public KeyIterator<K,V> clone() {
1460	<	if (last != null || (next != null && nextVal == null))
1461	<	throw new IllegalStateException();
1462	<	return new KeyIterator<K,V>(this, false);
1459	>	if (size == 0L)
1460	>	sizeCtl = 0;
1461	>	else {
1462	>	int n;
1463	>	if (size >= (long)(MAXIMUM_CAPACITY >>> 1))
1464	>	n = MAXIMUM_CAPACITY;
1465	>	else {
1466	>	int sz = (int)size;
1467	>	n = tableSizeFor(sz + (sz >>> 1) + 1);
1468	>	}
1469	>	@SuppressWarnings("unchecked")
1470	>	Node<K,V>[] tab = (Node<K,V>[])new Node<?,?>[n];
1471	>	int mask = n - 1;
1472	>	long added = 0L;
1473	>	while (p != null) {
1474	>	boolean insertAtFront;
1475	>	Node<K,V> next = p.next, first;
1476	>	int h = p.hash, j = h & mask;
1477	>	if ((first = tabAt(tab, j)) == null)
1478	>	insertAtFront = true;
1479	>	else {
1480	>	K k = p.key;
1481	>	if (first.hash < 0) {
1482	>	TreeBin<K,V> t = (TreeBin<K,V>)first;
1483	>	if (t.putTreeVal(h, k, p.val) == null)
1484	>	++added;
1485	>	insertAtFront = false;
1486	>	}
1487	>	else {
1488	>	int binCount = 0;
1489	>	insertAtFront = true;
1490	>	Node<K,V> q; K qk;
1491	>	for (q = first; q != null; q = q.next) {
1492	>	if (q.hash == h &&
1493	>	((qk = q.key) == k ||
1494	>	(qk != null && k.equals(qk)))) {
1495	>	insertAtFront = false;
1496	>	break;
1497	>	}
1498	>	++binCount;
1499	>	}
1500	>	if (insertAtFront && binCount >= TREEIFY_THRESHOLD) {
1501	>	insertAtFront = false;
1502	>	++added;
1503	>	p.next = first;
1504	>	TreeNode<K,V> hd = null, tl = null;
1505	>	for (q = p; q != null; q = q.next) {
1506	>	TreeNode<K,V> t = new TreeNode<K,V>
1507	>	(q.hash, q.key, q.val, null, null);
1508	>	if ((t.prev = tl) == null)
1509	>	hd = t;
1510	>	else
1511	>	tl.next = t;
1512	>	tl = t;
1513	>	}
1514	>	setTabAt(tab, j, new TreeBin<K,V>(hd));
1515	>	}
1516	>	}
1517	>	}
1518	>	if (insertAtFront) {
1519	>	++added;
1520	>	p.next = first;
1521	>	setTabAt(tab, j, p);
1522	>	}
1523	>	p = next;
1524	>	}
1525	>	table = tab;
1526	>	sizeCtl = n - (n >>> 2);
1527	>	baseCount = added;
1528		}
1529	+	}
1530
1531	<	@SuppressWarnings("unchecked")
1532	<	public final K next() {
1533	<	if (nextVal == null && advance() == null)
1534	<	throw new NoSuchElementException();
1535	<	Object k = nextKey;
1536	<	nextVal = null;
1537	<	return (K) k;
1531	>	// ConcurrentMap methods
1532	>
1533	>	/**
1534	>	* {@inheritDoc}
1535	>	*
1536	>	* @return the previous value associated with the specified key,
1537	>	*         or {@code null} if there was no mapping for the key
1538	>	* @throws NullPointerException if the specified key or value is null
1539	>	*/
1540	>	public V putIfAbsent(K key, V value) {
1541	>	return putVal(key, value, true);
1542	>	}
1543	>
1544	>	/**
1545	>	* {@inheritDoc}
1546	>	*
1547	>	* @throws NullPointerException if the specified key is null
1548	>	*/
1549	>	public boolean remove(Object key, Object value) {
1550	>	if (key == null)
1551	>	throw new NullPointerException();
1552	>	return value != null && replaceNode(key, null, value) != null;
1553	>	}
1554	>
1555	>	/**
1556	>	* {@inheritDoc}
1557	>	*
1558	>	* @throws NullPointerException if any of the arguments are null
1559	>	*/
1560	>	public boolean replace(K key, V oldValue, V newValue) {
1561	>	if (key == null || oldValue == null || newValue == null)
1562	>	throw new NullPointerException();
1563	>	return replaceNode(key, newValue, oldValue) != null;
1564	>	}
1565	>
1566	>	/**
1567	>	* {@inheritDoc}
1568	>	*
1569	>	* @return the previous value associated with the specified key,
1570	>	*         or {@code null} if there was no mapping for the key
1571	>	* @throws NullPointerException if the specified key or value is null
1572	>	*/
1573	>	public V replace(K key, V value) {
1574	>	if (key == null || value == null)
1575	>	throw new NullPointerException();
1576	>	return replaceNode(key, value, null);
1577	>	}
1578	>
1579	>	// Overrides of JDK8+ Map extension method defaults
1580	>
1581	>	/**
1582	>	* Returns the value to which the specified key is mapped, or the
1583	>	* given default value if this map contains no mapping for the
1584	>	* key.
1585	>	*
1586	>	* @param key the key whose associated value is to be returned
1587	>	* @param defaultValue the value to return if this map contains
1588	>	* no mapping for the given key
1589	>	* @return the mapping for the key, if present; else the default value
1590	>	* @throws NullPointerException if the specified key is null
1591	>	*/
1592	>	public V getOrDefault(Object key, V defaultValue) {
1593	>	V v;
1594	>	return (v = get(key)) == null ? defaultValue : v;
1595	>	}
1596	>
1597	>	public void forEach(BiAction<? super K, ? super V> action) {
1598	>	if (action == null) throw new NullPointerException();
1599	>	Node<K,V>[] t;
1600	>	if ((t = table) != null) {
1601	>	Traverser<K,V> it = new Traverser<K,V>(t, t.length, 0, t.length);
1602	>	for (Node<K,V> p; (p = it.advance()) != null; ) {
1603	>	action.apply(p.key, p.val);
1604	>	}
1605		}
1606	+	}
1607
1608	<	public final K nextElement() { return next(); }
1608	>	public void replaceAll(BiFun<? super K, ? super V, ? extends V> function) {
1609	>	if (function == null) throw new NullPointerException();
1610	>	Node<K,V>[] t;
1611	>	if ((t = table) != null) {
1612	>	Traverser<K,V> it = new Traverser<K,V>(t, t.length, 0, t.length);
1613	>	for (Node<K,V> p; (p = it.advance()) != null; ) {
1614	>	V oldValue = p.val;
1615	>	for (K key = p.key;;) {
1616	>	V newValue = function.apply(key, oldValue);
1617	>	if (newValue == null)
1618	>	throw new NullPointerException();
1619	>	if (replaceNode(key, newValue, oldValue) != null ||
1620	>	(oldValue = get(key)) == null)
1621	>	break;
1622	>	}
1623	>	}
1624	>	}
1625		}
1626
1627	<	static final class ValueIterator<K,V> extends InternalIterator<K,V>
1628	<	implements Spliterator<V>, Enumeration<V> {
1629	<	ValueIterator(ConcurrentHashMapV8<K, V> map) { super(map); }
1630	<	ValueIterator(InternalIterator<K,V> it, boolean split) {
1631	<	super(it, split);
1627	>	/**
1628	>	* If the specified key is not already associated with a value,
1629	>	* attempts to compute its value using the given mapping function
1630	>	* and enters it into this map unless {@code null}.  The entire
1631	>	* method invocation is performed atomically, so the function is
1632	>	* applied at most once per key.  Some attempted update operations
1633	>	* on this map by other threads may be blocked while computation
1634	>	* is in progress, so the computation should be short and simple,
1635	>	* and must not attempt to update any other mappings of this map.
1636	>	*
1637	>	* @param key key with which the specified value is to be associated
1638	>	* @param mappingFunction the function to compute a value
1639	>	* @return the current (existing or computed) value associated with
1640	>	*         the specified key, or null if the computed value is null
1641	>	* @throws NullPointerException if the specified key or mappingFunction
1642	>	*         is null
1643	>	* @throws IllegalStateException if the computation detectably
1644	>	*         attempts a recursive update to this map that would
1645	>	*         otherwise never complete
1646	>	* @throws RuntimeException or Error if the mappingFunction does so,
1647	>	*         in which case the mapping is left unestablished
1648	>	*/
1649	>	public V computeIfAbsent(K key, Fun<? super K, ? extends V> mappingFunction) {
1650	>	if (key == null || mappingFunction == null)
1651	>	throw new NullPointerException();
1652	>	int h = spread(key.hashCode());
1653	>	V val = null;
1654	>	int binCount = 0;
1655	>	for (Node<K,V>[] tab = table;;) {
1656	>	Node<K,V> f; int n, i, fh;
1657	>	if (tab == null || (n = tab.length) == 0)
1658	>	tab = initTable();
1659	>	else if ((f = tabAt(tab, i = (n - 1) & h)) == null) {
1660	>	Node<K,V> r = new ReservationNode<K,V>();
1661	>	synchronized (r) {
1662	>	if (casTabAt(tab, i, null, r)) {
1663	>	binCount = 1;
1664	>	Node<K,V> node = null;
1665	>	try {
1666	>	if ((val = mappingFunction.apply(key)) != null)
1667	>	node = new Node<K,V>(h, key, val, null);
1668	>	} finally {
1669	>	setTabAt(tab, i, node);
1670	>	}
1671	>	}
1672	>	}
1673	>	if (binCount != 0)
1674	>	break;
1675	>	}
1676	>	else if ((fh = f.hash) == MOVED)
1677	>	tab = helpTransfer(tab, f);
1678	>	else {
1679	>	boolean added = false;
1680	>	synchronized (f) {
1681	>	if (tabAt(tab, i) == f) {
1682	>	if (fh >= 0) {
1683	>	binCount = 1;
1684	>	for (Node<K,V> e = f;; ++binCount) {
1685	>	K ek; V ev;
1686	>	if (e.hash == h &&
1687	>	((ek = e.key) == key ||
1688	>	(ek != null && key.equals(ek)))) {
1689	>	val = e.val;
1690	>	break;
1691	>	}
1692	>	Node<K,V> pred = e;
1693	>	if ((e = e.next) == null) {
1694	>	if ((val = mappingFunction.apply(key)) != null) {
1695	>	added = true;
1696	>	pred.next = new Node<K,V>(h, key, val, null);
1697	>	}
1698	>	break;
1699	>	}
1700	>	}
1701	>	}
1702	>	else if (f instanceof TreeBin) {
1703	>	binCount = 2;
1704	>	TreeBin<K,V> t = (TreeBin<K,V>)f;
1705	>	TreeNode<K,V> r, p;
1706	>	if ((r = t.root) != null &&
1707	>	(p = r.findTreeNode(h, key, null)) != null)
1708	>	val = p.val;
1709	>	else if ((val = mappingFunction.apply(key)) != null) {
1710	>	added = true;
1711	>	t.putTreeVal(h, key, val);
1712	>	}
1713	>	}
1714	>	}
1715	>	}
1716	>	if (binCount != 0) {
1717	>	if (binCount >= TREEIFY_THRESHOLD)
1718	>	treeifyBin(tab, i);
1719	>	if (!added)
1720	>	return val;
1721	>	break;
1722	>	}
1723	>	}
1724		}
1725	<	public ValueIterator<K,V> split() {
1726	<	if (last != null || (next != null && nextVal == null))
1727	<	throw new IllegalStateException();
1728	<	return new ValueIterator<K,V>(this, true);
1725	>	if (val != null)
1726	>	addCount(1L, binCount);
1727	>	return val;
1728	>	}
1729	>
1730	>	/**
1731	>	* If the value for the specified key is present, attempts to
1732	>	* compute a new mapping given the key and its current mapped
1733	>	* value.  The entire method invocation is performed atomically.
1734	>	* Some attempted update operations on this map by other threads
1735	>	* may be blocked while computation is in progress, so the
1736	>	* computation should be short and simple, and must not attempt to
1737	>	* update any other mappings of this map.
1738	>	*
1739	>	* @param key key with which a value may be associated
1740	>	* @param remappingFunction the function to compute a value
1741	>	* @return the new value associated with the specified key, or null if none
1742	>	* @throws NullPointerException if the specified key or remappingFunction
1743	>	*         is null
1744	>	* @throws IllegalStateException if the computation detectably
1745	>	*         attempts a recursive update to this map that would
1746	>	*         otherwise never complete
1747	>	* @throws RuntimeException or Error if the remappingFunction does so,
1748	>	*         in which case the mapping is unchanged
1749	>	*/
1750	>	public V computeIfPresent(K key, BiFun<? super K, ? super V, ? extends V> remappingFunction) {
1751	>	if (key == null || remappingFunction == null)
1752	>	throw new NullPointerException();
1753	>	int h = spread(key.hashCode());
1754	>	V val = null;
1755	>	int delta = 0;
1756	>	int binCount = 0;
1757	>	for (Node<K,V>[] tab = table;;) {
1758	>	Node<K,V> f; int n, i, fh;
1759	>	if (tab == null || (n = tab.length) == 0)
1760	>	tab = initTable();
1761	>	else if ((f = tabAt(tab, i = (n - 1) & h)) == null)
1762	>	break;
1763	>	else if ((fh = f.hash) == MOVED)
1764	>	tab = helpTransfer(tab, f);
1765	>	else {
1766	>	synchronized (f) {
1767	>	if (tabAt(tab, i) == f) {
1768	>	if (fh >= 0) {
1769	>	binCount = 1;
1770	>	for (Node<K,V> e = f, pred = null;; ++binCount) {
1771	>	K ek;
1772	>	if (e.hash == h &&
1773	>	((ek = e.key) == key ||
1774	>	(ek != null && key.equals(ek)))) {
1775	>	val = remappingFunction.apply(key, e.val);
1776	>	if (val != null)
1777	>	e.val = val;
1778	>	else {
1779	>	delta = -1;
1780	>	Node<K,V> en = e.next;
1781	>	if (pred != null)
1782	>	pred.next = en;
1783	>	else
1784	>	setTabAt(tab, i, en);
1785	>	}
1786	>	break;
1787	>	}
1788	>	pred = e;
1789	>	if ((e = e.next) == null)
1790	>	break;
1791	>	}
1792	>	}
1793	>	else if (f instanceof TreeBin) {
1794	>	binCount = 2;
1795	>	TreeBin<K,V> t = (TreeBin<K,V>)f;
1796	>	TreeNode<K,V> r, p;
1797	>	if ((r = t.root) != null &&
1798	>	(p = r.findTreeNode(h, key, null)) != null) {
1799	>	val = remappingFunction.apply(key, p.val);
1800	>	if (val != null)
1801	>	p.val = val;
1802	>	else {
1803	>	delta = -1;
1804	>	if (t.removeTreeNode(p))
1805	>	setTabAt(tab, i, untreeify(t.first));
1806	>	}
1807	>	}
1808	>	}
1809	>	}
1810	>	}
1811	>	if (binCount != 0)
1812	>	break;
1813	>	}
1814	>	}
1815	>	if (delta != 0)
1816	>	addCount((long)delta, binCount);
1817	>	return val;
1818	>	}
1819	>
1820	>	/**
1821	>	* Attempts to compute a mapping for the specified key and its
1822	>	* current mapped value (or {@code null} if there is no current
1823	>	* mapping). The entire method invocation is performed atomically.
1824	>	* Some attempted update operations on this map by other threads
1825	>	* may be blocked while computation is in progress, so the
1826	>	* computation should be short and simple, and must not attempt to
1827	>	* update any other mappings of this Map.
1828	>	*
1829	>	* @param key key with which the specified value is to be associated
1830	>	* @param remappingFunction the function to compute a value
1831	>	* @return the new value associated with the specified key, or null if none
1832	>	* @throws NullPointerException if the specified key or remappingFunction
1833	>	*         is null
1834	>	* @throws IllegalStateException if the computation detectably
1835	>	*         attempts a recursive update to this map that would
1836	>	*         otherwise never complete
1837	>	* @throws RuntimeException or Error if the remappingFunction does so,
1838	>	*         in which case the mapping is unchanged
1839	>	*/
1840	>	public V compute(K key,
1841	>	BiFun<? super K, ? super V, ? extends V> remappingFunction) {
1842	>	if (key == null || remappingFunction == null)
1843	>	throw new NullPointerException();
1844	>	int h = spread(key.hashCode());
1845	>	V val = null;
1846	>	int delta = 0;
1847	>	int binCount = 0;
1848	>	for (Node<K,V>[] tab = table;;) {
1849	>	Node<K,V> f; int n, i, fh;
1850	>	if (tab == null || (n = tab.length) == 0)
1851	>	tab = initTable();
1852	>	else if ((f = tabAt(tab, i = (n - 1) & h)) == null) {
1853	>	Node<K,V> r = new ReservationNode<K,V>();
1854	>	synchronized (r) {
1855	>	if (casTabAt(tab, i, null, r)) {
1856	>	binCount = 1;
1857	>	Node<K,V> node = null;
1858	>	try {
1859	>	if ((val = remappingFunction.apply(key, null)) != null) {
1860	>	delta = 1;
1861	>	node = new Node<K,V>(h, key, val, null);
1862	>	}
1863	>	} finally {
1864	>	setTabAt(tab, i, node);
1865	>	}
1866	>	}
1867	>	}
1868	>	if (binCount != 0)
1869	>	break;
1870	>	}
1871	>	else if ((fh = f.hash) == MOVED)
1872	>	tab = helpTransfer(tab, f);
1873	>	else {
1874	>	synchronized (f) {
1875	>	if (tabAt(tab, i) == f) {
1876	>	if (fh >= 0) {
1877	>	binCount = 1;
1878	>	for (Node<K,V> e = f, pred = null;; ++binCount) {
1879	>	K ek;
1880	>	if (e.hash == h &&
1881	>	((ek = e.key) == key ||
1882	>	(ek != null && key.equals(ek)))) {
1883	>	val = remappingFunction.apply(key, e.val);
1884	>	if (val != null)
1885	>	e.val = val;
1886	>	else {
1887	>	delta = -1;
1888	>	Node<K,V> en = e.next;
1889	>	if (pred != null)
1890	>	pred.next = en;
1891	>	else
1892	>	setTabAt(tab, i, en);
1893	>	}
1894	>	break;
1895	>	}
1896	>	pred = e;
1897	>	if ((e = e.next) == null) {
1898	>	val = remappingFunction.apply(key, null);
1899	>	if (val != null) {
1900	>	delta = 1;
1901	>	pred.next =
1902	>	new Node<K,V>(h, key, val, null);
1903	>	}
1904	>	break;
1905	>	}
1906	>	}
1907	>	}
1908	>	else if (f instanceof TreeBin) {
1909	>	binCount = 1;
1910	>	TreeBin<K,V> t = (TreeBin<K,V>)f;
1911	>	TreeNode<K,V> r, p;
1912	>	if ((r = t.root) != null)
1913	>	p = r.findTreeNode(h, key, null);
1914	>	else
1915	>	p = null;
1916	>	V pv = (p == null) ? null : p.val;
1917	>	val = remappingFunction.apply(key, pv);
1918	>	if (val != null) {
1919	>	if (p != null)
1920	>	p.val = val;
1921	>	else {
1922	>	delta = 1;
1923	>	t.putTreeVal(h, key, val);
1924	>	}
1925	>	}
1926	>	else if (p != null) {
1927	>	delta = -1;
1928	>	if (t.removeTreeNode(p))
1929	>	setTabAt(tab, i, untreeify(t.first));
1930	>	}
1931	>	}
1932	>	}
1933	>	}
1934	>	if (binCount != 0) {
1935	>	if (binCount >= TREEIFY_THRESHOLD)
1936	>	treeifyBin(tab, i);
1937	>	break;
1938	>	}
1939	>	}
1940		}
1941	+	if (delta != 0)
1942	+	addCount((long)delta, binCount);
1943	+	return val;
1944	+	}
1945	+
1946	+	/**
1947	+	* If the specified key is not already associated with a
1948	+	* (non-null) value, associates it with the given value.
1949	+	* Otherwise, replaces the value with the results of the given
1950	+	* remapping function, or removes if {@code null}. The entire
1951	+	* method invocation is performed atomically.  Some attempted
1952	+	* update operations on this map by other threads may be blocked
1953	+	* while computation is in progress, so the computation should be
1954	+	* short and simple, and must not attempt to update any other
1955	+	* mappings of this Map.
1956	+	*
1957	+	* @param key key with which the specified value is to be associated
1958	+	* @param value the value to use if absent
1959	+	* @param remappingFunction the function to recompute a value if present
1960	+	* @return the new value associated with the specified key, or null if none
1961	+	* @throws NullPointerException if the specified key or the
1962	+	*         remappingFunction is null
1963	+	* @throws RuntimeException or Error if the remappingFunction does so,
1964	+	*         in which case the mapping is unchanged
1965	+	*/
1966	+	public V merge(K key, V value, BiFun<? super V, ? super V, ? extends V> remappingFunction) {
1967	+	if (key == null || value == null || remappingFunction == null)
1968	+	throw new NullPointerException();
1969	+	int h = spread(key.hashCode());
1970	+	V val = null;
1971	+	int delta = 0;
1972	+	int binCount = 0;
1973	+	for (Node<K,V>[] tab = table;;) {
1974	+	Node<K,V> f; int n, i, fh;
1975	+	if (tab == null || (n = tab.length) == 0)
1976	+	tab = initTable();
1977	+	else if ((f = tabAt(tab, i = (n - 1) & h)) == null) {
1978	+	if (casTabAt(tab, i, null, new Node<K,V>(h, key, value, null))) {
1979	+	delta = 1;
1980	+	val = value;
1981	+	break;
1982	+	}
1983	+	}
1984	+	else if ((fh = f.hash) == MOVED)
1985	+	tab = helpTransfer(tab, f);
1986	+	else {
1987	+	synchronized (f) {
1988	+	if (tabAt(tab, i) == f) {
1989	+	if (fh >= 0) {
1990	+	binCount = 1;
1991	+	for (Node<K,V> e = f, pred = null;; ++binCount) {
1992	+	K ek;
1993	+	if (e.hash == h &&
1994	+	((ek = e.key) == key ||
1995	+	(ek != null && key.equals(ek)))) {
1996	+	val = remappingFunction.apply(e.val, value);
1997	+	if (val != null)
1998	+	e.val = val;
1999	+	else {
2000	+	delta = -1;
2001	+	Node<K,V> en = e.next;
2002	+	if (pred != null)
2003	+	pred.next = en;
2004	+	else
2005	+	setTabAt(tab, i, en);
2006	+	}
2007	+	break;
2008	+	}
2009	+	pred = e;
2010	+	if ((e = e.next) == null) {
2011	+	delta = 1;
2012	+	val = value;
2013	+	pred.next =
2014	+	new Node<K,V>(h, key, val, null);
2015	+	break;
2016	+	}
2017	+	}
2018	+	}
2019	+	else if (f instanceof TreeBin) {
2020	+	binCount = 2;
2021	+	TreeBin<K,V> t = (TreeBin<K,V>)f;
2022	+	TreeNode<K,V> r = t.root;
2023	+	TreeNode<K,V> p = (r == null) ? null :
2024	+	r.findTreeNode(h, key, null);
2025	+	val = (p == null) ? value :
2026	+	remappingFunction.apply(p.val, value);
2027	+	if (val != null) {
2028	+	if (p != null)
2029	+	p.val = val;
2030	+	else {
2031	+	delta = 1;
2032	+	t.putTreeVal(h, key, val);
2033	+	}
2034	+	}
2035	+	else if (p != null) {
2036	+	delta = -1;
2037	+	if (t.removeTreeNode(p))
2038	+	setTabAt(tab, i, untreeify(t.first));
2039	+	}
2040	+	}
2041	+	}
2042	+	}
2043	+	if (binCount != 0) {
2044	+	if (binCount >= TREEIFY_THRESHOLD)
2045	+	treeifyBin(tab, i);
2046	+	break;
2047	+	}
2048	+	}
2049	+	}
2050	+	if (delta != 0)
2051	+	addCount((long)delta, binCount);
2052	+	return val;
2053	+	}
2054	+
2055	+	// Hashtable legacy methods
2056	+
2057	+	/**
2058	+	* Legacy method testing if some key maps into the specified value
2059	+	* in this table.  This method is identical in functionality to
2060	+	* {@link #containsValue(Object)}, and exists solely to ensure
2061	+	* full compatibility with class {@link java.util.Hashtable},
2062	+	* which supported this method prior to introduction of the
2063	+	* Java Collections framework.
2064	+	*
2065	+	* @param  value a value to search for
2066	+	* @return {@code true} if and only if some key maps to the
2067	+	*         {@code value} argument in this table as
2068	+	*         determined by the {@code equals} method;
2069	+	*         {@code false} otherwise
2070	+	* @throws NullPointerException if the specified value is null
2071	+	*/
2072	+	@Deprecated public boolean contains(Object value) {
2073	+	return containsValue(value);
2074	+	}
2075	+
2076	+	/**
2077	+	* Returns an enumeration of the keys in this table.
2078	+	*
2079	+	* @return an enumeration of the keys in this table
2080	+	* @see #keySet()
2081	+	*/
2082	+	public Enumeration<K> keys() {
2083	+	Node<K,V>[] t;
2084	+	int f = (t = table) == null ? 0 : t.length;
2085	+	return new KeyIterator<K,V>(t, f, 0, f, this);
2086	+	}
2087	+
2088	+	/**
2089	+	* Returns an enumeration of the values in this table.
2090	+	*
2091	+	* @return an enumeration of the values in this table
2092	+	* @see #values()
2093	+	*/
2094	+	public Enumeration<V> elements() {
2095	+	Node<K,V>[] t;
2096	+	int f = (t = table) == null ? 0 : t.length;
2097	+	return new ValueIterator<K,V>(t, f, 0, f, this);
2098	+	}
2099	+
2100	+	// ConcurrentHashMapV8-only methods
2101	+
2102	+	/**
2103	+	* Returns the number of mappings. This method should be used
2104	+	* instead of {@link #size} because a ConcurrentHashMapV8 may
2105	+	* contain more mappings than can be represented as an int. The
2106	+	* value returned is an estimate; the actual count may differ if
2107	+	* there are concurrent insertions or removals.
2108	+	*
2109	+	* @return the number of mappings
2110	+	* @since 1.8
2111	+	*/
2112	+	public long mappingCount() {
2113	+	long n = sumCount();
2114	+	return (n < 0L) ? 0L : n; // ignore transient negative values
2115	+	}
2116	+
2117	+	/**
2118	+	* Creates a new {@link Set} backed by a ConcurrentHashMapV8
2119	+	* from the given type to {@code Boolean.TRUE}.
2120	+	*
2121	+	* @return the new set
2122	+	* @since 1.8
2123	+	*/
2124	+	public static <K> KeySetView<K,Boolean> newKeySet() {
2125	+	return new KeySetView<K,Boolean>
2126	+	(new ConcurrentHashMapV8<K,Boolean>(), Boolean.TRUE);
2127	+	}
2128	+
2129	+	/**
2130	+	* Creates a new {@link Set} backed by a ConcurrentHashMapV8
2131	+	* from the given type to {@code Boolean.TRUE}.
2132	+	*
2133	+	* @param initialCapacity The implementation performs internal
2134	+	* sizing to accommodate this many elements.
2135	+	* @return the new set
2136	+	* @throws IllegalArgumentException if the initial capacity of
2137	+	* elements is negative
2138	+	* @since 1.8
2139	+	*/
2140	+	public static <K> KeySetView<K,Boolean> newKeySet(int initialCapacity) {
2141	+	return new KeySetView<K,Boolean>
2142	+	(new ConcurrentHashMapV8<K,Boolean>(initialCapacity), Boolean.TRUE);
2143	+	}
2144	+
2145	+	/**
2146	+	* Returns a {@link Set} view of the keys in this map, using the
2147	+	* given common mapped value for any additions (i.e., {@link
2148	+	* Collection#add} and {@link Collection#addAll(Collection)}).
2149	+	* This is of course only appropriate if it is acceptable to use
2150	+	* the same value for all additions from this view.
2151	+	*
2152	+	* @param mappedValue the mapped value to use for any additions
2153	+	* @return the set view
2154	+	* @throws NullPointerException if the mappedValue is null
2155	+	*/
2156	+	public KeySetView<K,V> keySet(V mappedValue) {
2157	+	if (mappedValue == null)
2158	+	throw new NullPointerException();
2159	+	return new KeySetView<K,V>(this, mappedValue);
2160	+	}
2161	+
2162	+	/* ---------------- Special Nodes -------------- */
2163	+
2164	+	/**
2165	+	* A node inserted at head of bins during transfer operations.
2166	+	*/
2167	+	static final class ForwardingNode<K,V> extends Node<K,V> {
2168	+	final Node<K,V>[] nextTable;
2169	+	ForwardingNode(Node<K,V>[] tab) {
2170	+	super(MOVED, null, null, null);
2171	+	this.nextTable = tab;
2172	+	}
2173	+
2174	+	Node<K,V> find(int h, Object k) {
2175	+	// loop to avoid arbitrarily deep recursion on forwarding nodes
2176	+	outer: for (Node<K,V>[] tab = nextTable;;) {
2177	+	Node<K,V> e; int n;
2178	+	if (k == null || tab == null || (n = tab.length) == 0 ||
2179	+	(e = tabAt(tab, (n - 1) & h)) == null)
2180	+	return null;
2181	+	for (;;) {
2182	+	int eh; K ek;
2183	+	if ((eh = e.hash) == h &&
2184	+	((ek = e.key) == k || (ek != null && k.equals(ek))))
2185	+	return e;
2186	+	if (eh < 0) {
2187	+	if (e instanceof ForwardingNode) {
2188	+	tab = ((ForwardingNode<K,V>)e).nextTable;
2189	+	continue outer;
2190	+	}
2191	+	else
2192	+	return e.find(h, k);
2193	+	}
2194	+	if ((e = e.next) == null)
2195	+	return null;
2196	+	}
2197	+	}
2198	+	}
2199	+	}
2200	+
2201	+	/**
2202	+	* A place-holder node used in computeIfAbsent and compute
2203	+	*/
2204	+	static final class ReservationNode<K,V> extends Node<K,V> {
2205	+	ReservationNode() {
2206	+	super(RESERVED, null, null, null);
2207	+	}
2208	+
2209	+	Node<K,V> find(int h, Object k) {
2210	+	return null;
2211	+	}
2212	+	}
2213	+
2214	+	/* ---------------- Table Initialization and Resizing -------------- */
2215	+
2216	+	/**
2217	+	* Returns the stamp bits for resizing a table of size n.
2218	+	* Must be negative when shifted left by RESIZE_STAMP_SHIFT.
2219	+	*/
2220	+	static final int resizeStamp(int n) {
2221	+	return Integer.numberOfLeadingZeros(n) | (1 << (RESIZE_STAMP_BITS - 1));
2222	+	}
2223	+
2224	+	/**
2225	+	* Initializes table, using the size recorded in sizeCtl.
2226	+	*/
2227	+	private final Node<K,V>[] initTable() {
2228	+	Node<K,V>[] tab; int sc;
2229	+	while ((tab = table) == null || tab.length == 0) {
2230	+	if ((sc = sizeCtl) < 0)
2231	+	Thread.yield(); // lost initialization race; just spin
2232	+	else if (U.compareAndSwapInt(this, SIZECTL, sc, -1)) {
2233	+	try {
2234	+	if ((tab = table) == null || tab.length == 0) {
2235	+	int n = (sc > 0) ? sc : DEFAULT_CAPACITY;
2236	+	@SuppressWarnings("unchecked")
2237	+	Node<K,V>[] nt = (Node<K,V>[])new Node<?,?>[n];
2238	+	table = tab = nt;
2239	+	sc = n - (n >>> 2);
2240	+	}
2241	+	} finally {
2242	+	sizeCtl = sc;
2243	+	}
2244	+	break;
2245	+	}
2246	+	}
2247	+	return tab;
2248	+	}
2249	+
2250	+	/**
2251	+	* Adds to count, and if table is too small and not already
2252	+	* resizing, initiates transfer. If already resizing, helps
2253	+	* perform transfer if work is available.  Rechecks occupancy
2254	+	* after a transfer to see if another resize is already needed
2255	+	* because resizings are lagging additions.
2256	+	*
2257	+	* @param x the count to add
2258	+	* @param check if <0, don't check resize, if <= 1 only check if uncontended
2259	+	*/
2260	+	private final void addCount(long x, int check) {
2261	+	CounterCell[] as; long b, s;
2262	+	if ((as = counterCells) != null ||
2263	+	!U.compareAndSwapLong(this, BASECOUNT, b = baseCount, s = b + x)) {
2264	+	CounterHashCode hc; CounterCell a; long v; int m;
2265	+	boolean uncontended = true;
2266	+	if ((hc = threadCounterHashCode.get()) == null ||
2267	+	as == null || (m = as.length - 1) < 0 ||
2268	+	(a = as[m & hc.code]) == null ||
2269	+	!(uncontended =
2270	+	U.compareAndSwapLong(a, CELLVALUE, v = a.value, v + x))) {
2271	+	fullAddCount(x, hc, uncontended);
2272	+	return;
2273	+	}
2274	+	if (check <= 1)
2275	+	return;
2276	+	s = sumCount();
2277	+	}
2278	+	if (check >= 0) {
2279	+	Node<K,V>[] tab, nt; int n, sc;
2280	+	while (s >= (long)(sc = sizeCtl) && (tab = table) != null &&
2281	+	(n = tab.length) < MAXIMUM_CAPACITY) {
2282	+	int rs = resizeStamp(n);
2283	+	if (sc < 0) {
2284	+	if ((sc >>> RESIZE_STAMP_SHIFT) != rs || sc == rs + 1 ||
2285	+	sc == rs + MAX_RESIZERS || (nt = nextTable) == null ||
2286	+	transferIndex <= 0)
2287	+	break;
2288	+	if (U.compareAndSwapInt(this, SIZECTL, sc, sc + 1))
2289	+	transfer(tab, nt);
2290	+	}
2291	+	else if (U.compareAndSwapInt(this, SIZECTL, sc,
2292	+	(rs << RESIZE_STAMP_SHIFT) + 2))
2293	+	transfer(tab, null);
2294	+	s = sumCount();
2295	+	}
2296	+	}
2297	+	}
2298	+
2299	+	/**
2300	+	* Helps transfer if a resize is in progress.
2301	+	*/
2302	+	final Node<K,V>[] helpTransfer(Node<K,V>[] tab, Node<K,V> f) {
2303	+	Node<K,V>[] nextTab; int sc;
2304	+	if (tab != null && (f instanceof ForwardingNode) &&
2305	+	(nextTab = ((ForwardingNode<K,V>)f).nextTable) != null) {
2306	+	int rs = resizeStamp(tab.length);
2307	+	while (nextTab == nextTable && table == tab &&
2308	+	(sc = sizeCtl) < 0) {
2309	+	if ((sc >>> RESIZE_STAMP_SHIFT) != rs || sc == rs + 1 ||
2310	+	sc == rs + MAX_RESIZERS || transferIndex <= 0)
2311	+	break;
2312	+	if (U.compareAndSwapInt(this, SIZECTL, sc, sc + 1)) {
2313	+	transfer(tab, nextTab);
2314	+	break;
2315	+	}
2316	+	}
2317	+	return nextTab;
2318	+	}
2319	+	return table;
2320	+	}
2321	+
2322	+	/**
2323	+	* Tries to presize table to accommodate the given number of elements.
2324	+	*
2325	+	* @param size number of elements (doesn't need to be perfectly accurate)
2326	+	*/
2327	+	private final void tryPresize(int size) {
2328	+	int c = (size >= (MAXIMUM_CAPACITY >>> 1)) ? MAXIMUM_CAPACITY :
2329	+	tableSizeFor(size + (size >>> 1) + 1);
2330	+	int sc;
2331	+	while ((sc = sizeCtl) >= 0) {
2332	+	Node<K,V>[] tab = table; int n;
2333	+	if (tab == null || (n = tab.length) == 0) {
2334	+	n = (sc > c) ? sc : c;
2335	+	if (U.compareAndSwapInt(this, SIZECTL, sc, -1)) {
2336	+	try {
2337	+	if (table == tab) {
2338	+	@SuppressWarnings("unchecked")
2339	+	Node<K,V>[] nt = (Node<K,V>[])new Node<?,?>[n];
2340	+	table = nt;
2341	+	sc = n - (n >>> 2);
2342	+	}
2343	+	} finally {
2344	+	sizeCtl = sc;
2345	+	}
2346	+	}
2347	+	}
2348	+	else if (c <= sc || n >= MAXIMUM_CAPACITY)
2349	+	break;
2350	+	else if (tab == table) {
2351	+	int rs = resizeStamp(n);
2352	+	if (sc < 0) {
2353	+	Node<K,V>[] nt;
2354	+	if ((sc >>> RESIZE_STAMP_SHIFT) != rs || sc == rs + 1 ||
2355	+	sc == rs + MAX_RESIZERS || (nt = nextTable) == null ||
2356	+	transferIndex <= 0)
2357	+	break;
2358	+	if (U.compareAndSwapInt(this, SIZECTL, sc, sc + 1))
2359	+	transfer(tab, nt);
2360	+	}
2361	+	else if (U.compareAndSwapInt(this, SIZECTL, sc,
2362	+	(rs << RESIZE_STAMP_SHIFT) + 2))
2363	+	transfer(tab, null);
2364	+	}
2365	+	}
2366	+	}
2367	+
2368	+	/**
2369	+	* Moves and/or copies the nodes in each bin to new table. See
2370	+	* above for explanation.
2371	+	*/
2372	+	private final void transfer(Node<K,V>[] tab, Node<K,V>[] nextTab) {
2373	+	int n = tab.length, stride;
2374	+	if ((stride = (NCPU > 1) ? (n >>> 3) / NCPU : n) < MIN_TRANSFER_STRIDE)
2375	+	stride = MIN_TRANSFER_STRIDE; // subdivide range
2376	+	if (nextTab == null) {            // initiating
2377	+	try {
2378	+	@SuppressWarnings("unchecked")
2379	+	Node<K,V>[] nt = (Node<K,V>[])new Node<?,?>[n << 1];
2380	+	nextTab = nt;
2381	+	} catch (Throwable ex) {      // try to cope with OOME
2382	+	sizeCtl = Integer.MAX_VALUE;
2383	+	return;
2384	+	}
2385	+	nextTable = nextTab;
2386	+	transferIndex = n;
2387	+	}
2388	+	int nextn = nextTab.length;
2389	+	ForwardingNode<K,V> fwd = new ForwardingNode<K,V>(nextTab);
2390	+	boolean advance = true;
2391	+	boolean finishing = false; // to ensure sweep before committing nextTab
2392	+	for (int i = 0, bound = 0;;) {
2393	+	Node<K,V> f; int fh;
2394	+	while (advance) {
2395	+	int nextIndex, nextBound;
2396	+	if (--i >= bound || finishing)
2397	+	advance = false;
2398	+	else if ((nextIndex = transferIndex) <= 0) {
2399	+	i = -1;
2400	+	advance = false;
2401	+	}
2402	+	else if (U.compareAndSwapInt
2403	+	(this, TRANSFERINDEX, nextIndex,
2404	+	nextBound = (nextIndex > stride ?
2405	+	nextIndex - stride : 0))) {
2406	+	bound = nextBound;
2407	+	i = nextIndex - 1;
2408	+	advance = false;
2409	+	}
2410	+	}
2411	+	if (i < 0 || i >= n || i + n >= nextn) {
2412	+	int sc;
2413	+	if (finishing) {
2414	+	nextTable = null;
2415	+	table = nextTab;
2416	+	sizeCtl = (n << 1) - (n >>> 1);
2417	+	return;
2418	+	}
2419	+	if (U.compareAndSwapInt(this, SIZECTL, sc = sizeCtl, sc - 1)) {
2420	+	if ((sc - 2) != resizeStamp(n) << RESIZE_STAMP_SHIFT)
2421	+	return;
2422	+	finishing = advance = true;
2423	+	i = n; // recheck before commit
2424	+	}
2425	+	}
2426	+	else if ((f = tabAt(tab, i)) == null)
2427	+	advance = casTabAt(tab, i, null, fwd);
2428	+	else if ((fh = f.hash) == MOVED)
2429	+	advance = true; // already processed
2430	+	else {
2431	+	synchronized (f) {
2432	+	if (tabAt(tab, i) == f) {
2433	+	Node<K,V> ln, hn;
2434	+	if (fh >= 0) {
2435	+	int runBit = fh & n;
2436	+	Node<K,V> lastRun = f;
2437	+	for (Node<K,V> p = f.next; p != null; p = p.next) {
2438	+	int b = p.hash & n;
2439	+	if (b != runBit) {
2440	+	runBit = b;
2441	+	lastRun = p;
2442	+	}
2443	+	}
2444	+	if (runBit == 0) {
2445	+	ln = lastRun;
2446	+	hn = null;
2447	+	}
2448	+	else {
2449	+	hn = lastRun;
2450	+	ln = null;
2451	+	}
2452	+	for (Node<K,V> p = f; p != lastRun; p = p.next) {
2453	+	int ph = p.hash; K pk = p.key; V pv = p.val;
2454	+	if ((ph & n) == 0)
2455	+	ln = new Node<K,V>(ph, pk, pv, ln);
2456	+	else
2457	+	hn = new Node<K,V>(ph, pk, pv, hn);
2458	+	}
2459	+	setTabAt(nextTab, i, ln);
2460	+	setTabAt(nextTab, i + n, hn);
2461	+	setTabAt(tab, i, fwd);
2462	+	advance = true;
2463	+	}
2464	+	else if (f instanceof TreeBin) {
2465	+	TreeBin<K,V> t = (TreeBin<K,V>)f;
2466	+	TreeNode<K,V> lo = null, loTail = null;
2467	+	TreeNode<K,V> hi = null, hiTail = null;
2468	+	int lc = 0, hc = 0;
2469	+	for (Node<K,V> e = t.first; e != null; e = e.next) {
2470	+	int h = e.hash;
2471	+	TreeNode<K,V> p = new TreeNode<K,V>
2472	+	(h, e.key, e.val, null, null);
2473	+	if ((h & n) == 0) {
2474	+	if ((p.prev = loTail) == null)
2475	+	lo = p;
2476	+	else
2477	+	loTail.next = p;
2478	+	loTail = p;
2479	+	++lc;
2480	+	}
2481	+	else {
2482	+	if ((p.prev = hiTail) == null)
2483	+	hi = p;
2484	+	else
2485	+	hiTail.next = p;
2486	+	hiTail = p;
2487	+	++hc;
2488	+	}
2489	+	}
2490	+	ln = (lc <= UNTREEIFY_THRESHOLD) ? untreeify(lo) :
2491	+	(hc != 0) ? new TreeBin<K,V>(lo) : t;
2492	+	hn = (hc <= UNTREEIFY_THRESHOLD) ? untreeify(hi) :
2493	+	(lc != 0) ? new TreeBin<K,V>(hi) : t;
2494	+	setTabAt(nextTab, i, ln);
2495	+	setTabAt(nextTab, i + n, hn);
2496	+	setTabAt(tab, i, fwd);
2497	+	advance = true;
2498	+	}
2499	+	}
2500	+	}
2501	+	}
2502	+	}
2503	+	}
2504	+
2505	+	/* ---------------- Conversion from/to TreeBins -------------- */
2506	+
2507	+	/**
2508	+	* Replaces all linked nodes in bin at given index unless table is
2509	+	* too small, in which case resizes instead.
2510	+	*/
2511	+	private final void treeifyBin(Node<K,V>[] tab, int index) {
2512	+	Node<K,V> b; int n, sc;
2513	+	if (tab != null) {
2514	+	if ((n = tab.length) < MIN_TREEIFY_CAPACITY)
2515	+	tryPresize(n << 1);
2516	+	else if ((b = tabAt(tab, index)) != null && b.hash >= 0) {
2517	+	synchronized (b) {
2518	+	if (tabAt(tab, index) == b) {
2519	+	TreeNode<K,V> hd = null, tl = null;
2520	+	for (Node<K,V> e = b; e != null; e = e.next) {
2521	+	TreeNode<K,V> p =
2522	+	new TreeNode<K,V>(e.hash, e.key, e.val,
2523	+	null, null);
2524	+	if ((p.prev = tl) == null)
2525	+	hd = p;
2526	+	else
2527	+	tl.next = p;
2528	+	tl = p;
2529	+	}
2530	+	setTabAt(tab, index, new TreeBin<K,V>(hd));
2531	+	}
2532	+	}
2533	+	}
2534	+	}
2535	+	}
2536	+
2537	+	/**
2538	+	* Returns a list on non-TreeNodes replacing those in given list.
2539	+	*/
2540	+	static <K,V> Node<K,V> untreeify(Node<K,V> b) {
2541	+	Node<K,V> hd = null, tl = null;
2542	+	for (Node<K,V> q = b; q != null; q = q.next) {
2543	+	Node<K,V> p = new Node<K,V>(q.hash, q.key, q.val, null);
2544	+	if (tl == null)
2545	+	hd = p;
2546	+	else
2547	+	tl.next = p;
2548	+	tl = p;
2549	+	}
2550	+	return hd;
2551	+	}
2552	+
2553	+	/* ---------------- TreeNodes -------------- */
2554	+
2555	+	/**
2556	+	* Nodes for use in TreeBins
2557	+	*/
2558	+	static final class TreeNode<K,V> extends Node<K,V> {
2559	+	TreeNode<K,V> parent;  // red-black tree links
2560	+	TreeNode<K,V> left;
2561	+	TreeNode<K,V> right;
2562	+	TreeNode<K,V> prev;    // needed to unlink next upon deletion
2563	+	boolean red;
2564	+
2565	+	TreeNode(int hash, K key, V val, Node<K,V> next,
2566	+	TreeNode<K,V> parent) {
2567	+	super(hash, key, val, next);
2568	+	this.parent = parent;
2569	+	}
2570	+
2571	+	Node<K,V> find(int h, Object k) {
2572	+	return findTreeNode(h, k, null);
2573	+	}
2574	+
2575	+	/**
2576	+	* Returns the TreeNode (or null if not found) for the given key
2577	+	* starting at given root.
2578	+	*/
2579	+	final TreeNode<K,V> findTreeNode(int h, Object k, Class<?> kc) {
2580	+	if (k != null) {
2581	+	TreeNode<K,V> p = this;
2582	+	do {
2583	+	int ph, dir; K pk; TreeNode<K,V> q;
2584	+	TreeNode<K,V> pl = p.left, pr = p.right;
2585	+	if ((ph = p.hash) > h)
2586	+	p = pl;
2587	+	else if (ph < h)
2588	+	p = pr;
2589	+	else if ((pk = p.key) == k || (pk != null && k.equals(pk)))
2590	+	return p;
2591	+	else if (pl == null)
2592	+	p = pr;
2593	+	else if (pr == null)
2594	+	p = pl;
2595	+	else if ((kc != null ||
2596	+	(kc = comparableClassFor(k)) != null) &&
2597	+	(dir = compareComparables(kc, k, pk)) != 0)
2598	+	p = (dir < 0) ? pl : pr;
2599	+	else if ((q = pr.findTreeNode(h, k, kc)) != null)
2600	+	return q;
2601	+	else
2602	+	p = pl;
2603	+	} while (p != null);
2604	+	}
2605	+	return null;
2606	+	}
2607	+	}
2608	+
2609	+	/* ---------------- TreeBins -------------- */
2610	+
2611	+	/**
2612	+	* TreeNodes used at the heads of bins. TreeBins do not hold user
2613	+	* keys or values, but instead point to list of TreeNodes and
2614	+	* their root. They also maintain a parasitic read-write lock
2615	+	* forcing writers (who hold bin lock) to wait for readers (who do
2616	+	* not) to complete before tree restructuring operations.
2617	+	*/
2618	+	static final class TreeBin<K,V> extends Node<K,V> {
2619	+	TreeNode<K,V> root;
2620	+	volatile TreeNode<K,V> first;
2621	+	volatile Thread waiter;
2622	+	volatile int lockState;
2623	+	// values for lockState
2624	+	static final int WRITER = 1; // set while holding write lock
2625	+	static final int WAITER = 2; // set when waiting for write lock
2626	+	static final int READER = 4; // increment value for setting read lock
2627	+
2628	+	/**
2629	+	* Tie-breaking utility for ordering insertions when equal
2630	+	* hashCodes and non-comparable. We don't require a total
2631	+	* order, just a consistent insertion rule to maintain
2632	+	* equivalence across rebalancings. Tie-breaking further than
2633	+	* necessary simplifies testing a bit.
2634	+	*/
2635	+	static int tieBreakOrder(Object a, Object b) {
2636	+	int d;
2637	+	if (a == null || b == null ||
2638	+	(d = a.getClass().getName().
2639	+	compareTo(b.getClass().getName())) == 0)
2640	+	d = (System.identityHashCode(a) <= System.identityHashCode(b) ?
2641	+	-1 : 1);
2642	+	return d;
2643	+	}
2644	+
2645	+	/**
2646	+	* Creates bin with initial set of nodes headed by b.
2647	+	*/
2648	+	TreeBin(TreeNode<K,V> b) {
2649	+	super(TREEBIN, null, null, null);
2650	+	this.first = b;
2651	+	TreeNode<K,V> r = null;
2652	+	for (TreeNode<K,V> x = b, next; x != null; x = next) {
2653	+	next = (TreeNode<K,V>)x.next;
2654	+	x.left = x.right = null;
2655	+	if (r == null) {
2656	+	x.parent = null;
2657	+	x.red = false;
2658	+	r = x;
2659	+	}
2660	+	else {
2661	+	K k = x.key;
2662	+	int h = x.hash;
2663	+	Class<?> kc = null;
2664	+	for (TreeNode<K,V> p = r;;) {
2665	+	int dir, ph;
2666	+	K pk = p.key;
2667	+	if ((ph = p.hash) > h)
2668	+	dir = -1;
2669	+	else if (ph < h)
2670	+	dir = 1;
2671	+	else if ((kc == null &&
2672	+	(kc = comparableClassFor(k)) == null) ||
2673	+	(dir = compareComparables(kc, k, pk)) == 0)
2674	+	dir = tieBreakOrder(k, pk);
2675	+	TreeNode<K,V> xp = p;
2676	+	if ((p = (dir <= 0) ? p.left : p.right) == null) {
2677	+	x.parent = xp;
2678	+	if (dir <= 0)
2679	+	xp.left = x;
2680	+	else
2681	+	xp.right = x;
2682	+	r = balanceInsertion(r, x);
2683	+	break;
2684	+	}
2685	+	}
2686	+	}
2687	+	}
2688	+	this.root = r;
2689	+	assert checkInvariants(root);
2690	+	}
2691	+
2692	+	/**
2693	+	* Acquires write lock for tree restructuring.
2694	+	*/
2695	+	private final void lockRoot() {
2696	+	if (!U.compareAndSwapInt(this, LOCKSTATE, 0, WRITER))
2697	+	contendedLock(); // offload to separate method
2698	+	}
2699	+
2700	+	/**
2701	+	* Releases write lock for tree restructuring.
2702	+	*/
2703	+	private final void unlockRoot() {
2704	+	lockState = 0;
2705	+	}
2706	+
2707	+	/**
2708	+	* Possibly blocks awaiting root lock.
2709	+	*/
2710	+	private final void contendedLock() {
2711	+	boolean waiting = false;
2712	+	for (int s;;) {
2713	+	if (((s = lockState) & ~WAITER) == 0) {
2714	+	if (U.compareAndSwapInt(this, LOCKSTATE, s, WRITER)) {
2715	+	if (waiting)
2716	+	waiter = null;
2717	+	return;
2718	+	}
2719	+	}
2720	+	else if ((s & WAITER) == 0) {
2721	+	if (U.compareAndSwapInt(this, LOCKSTATE, s, s | WAITER)) {
2722	+	waiting = true;
2723	+	waiter = Thread.currentThread();
2724	+	}
2725	+	}
2726	+	else if (waiting)
2727	+	LockSupport.park(this);
2728	+	}
2729	+	}
2730	+
2731	+	/**
2732	+	* Returns matching node or null if none. Tries to search
2733	+	* using tree comparisons from root, but continues linear
2734	+	* search when lock not available.
2735	+	*/
2736	+	final Node<K,V> find(int h, Object k) {
2737	+	if (k != null) {
2738	+	for (Node<K,V> e = first; e != null; ) {
2739	+	int s; K ek;
2740	+	if (((s = lockState) & (WAITER|WRITER)) != 0) {
2741	+	if (e.hash == h &&
2742	+	((ek = e.key) == k || (ek != null && k.equals(ek))))
2743	+	return e;
2744	+	e = e.next;
2745	+	}
2746	+	else if (U.compareAndSwapInt(this, LOCKSTATE, s,
2747	+	s + READER)) {
2748	+	TreeNode<K,V> r, p;
2749	+	try {
2750	+	p = ((r = root) == null ? null :
2751	+	r.findTreeNode(h, k, null));
2752	+	} finally {
2753	+	Thread w;
2754	+	int ls;
2755	+	do {} while (!U.compareAndSwapInt
2756	+	(this, LOCKSTATE,
2757	+	ls = lockState, ls - READER));
2758	+	if (ls == (READER|WAITER) && (w = waiter) != null)
2759	+	LockSupport.unpark(w);
2760	+	}
2761	+	return p;
2762	+	}
2763	+	}
2764	+	}
2765	+	return null;
2766	+	}
2767	+
2768	+	/**
2769	+	* Finds or adds a node.
2770	+	* @return null if added
2771	+	*/
2772	+	final TreeNode<K,V> putTreeVal(int h, K k, V v) {
2773	+	Class<?> kc = null;
2774	+	boolean searched = false;
2775	+	for (TreeNode<K,V> p = root;;) {
2776	+	int dir, ph; K pk;
2777	+	if (p == null) {
2778	+	first = root = new TreeNode<K,V>(h, k, v, null, null);
2779	+	break;
2780	+	}
2781	+	else if ((ph = p.hash) > h)
2782	+	dir = -1;
2783	+	else if (ph < h)
2784	+	dir = 1;
2785	+	else if ((pk = p.key) == k || (pk != null && k.equals(pk)))
2786	+	return p;
2787	+	else if ((kc == null &&
2788	+	(kc = comparableClassFor(k)) == null) ||
2789	+	(dir = compareComparables(kc, k, pk)) == 0) {
2790	+	if (!searched) {
2791	+	TreeNode<K,V> q, ch;
2792	+	searched = true;
2793	+	if (((ch = p.left) != null &&
2794	+	(q = ch.findTreeNode(h, k, kc)) != null) ||
2795	+	((ch = p.right) != null &&
2796	+	(q = ch.findTreeNode(h, k, kc)) != null))
2797	+	return q;
2798	+	}
2799	+	dir = tieBreakOrder(k, pk);
2800	+	}
2801	+
2802	+	TreeNode<K,V> xp = p;
2803	+	if ((p = (dir <= 0) ? p.left : p.right) == null) {
2804	+	TreeNode<K,V> x, f = first;
2805	+	first = x = new TreeNode<K,V>(h, k, v, f, xp);
2806	+	if (f != null)
2807	+	f.prev = x;
2808	+	if (dir <= 0)
2809	+	xp.left = x;
2810	+	else
2811	+	xp.right = x;
2812	+	if (!xp.red)
2813	+	x.red = true;
2814	+	else {
2815	+	lockRoot();
2816	+	try {
2817	+	root = balanceInsertion(root, x);
2818	+	} finally {
2819	+	unlockRoot();
2820	+	}
2821	+	}
2822	+	break;
2823	+	}
2824	+	}
2825	+	assert checkInvariants(root);
2826	+	return null;
2827	+	}
2828	+
2829	+	/**
2830	+	* Removes the given node, that must be present before this
2831	+	* call.  This is messier than typical red-black deletion code
2832	+	* because we cannot swap the contents of an interior node
2833	+	* with a leaf successor that is pinned by "next" pointers
2834	+	* that are accessible independently of lock. So instead we
2835	+	* swap the tree linkages.
2836	+	*
2837	+	* @return true if now too small, so should be untreeified
2838	+	*/
2839	+	final boolean removeTreeNode(TreeNode<K,V> p) {
2840	+	TreeNode<K,V> next = (TreeNode<K,V>)p.next;
2841	+	TreeNode<K,V> pred = p.prev;  // unlink traversal pointers
2842	+	TreeNode<K,V> r, rl;
2843	+	if (pred == null)
2844	+	first = next;
2845	+	else
2846	+	pred.next = next;
2847	+	if (next != null)
2848	+	next.prev = pred;
2849	+	if (first == null) {
2850	+	root = null;
2851	+	return true;
2852	+	}
2853	+	if ((r = root) == null || r.right == null || // too small
2854	+	(rl = r.left) == null || rl.left == null)
2855	+	return true;
2856	+	lockRoot();
2857	+	try {
2858	+	TreeNode<K,V> replacement;
2859	+	TreeNode<K,V> pl = p.left;
2860	+	TreeNode<K,V> pr = p.right;
2861	+	if (pl != null && pr != null) {
2862	+	TreeNode<K,V> s = pr, sl;
2863	+	while ((sl = s.left) != null) // find successor
2864	+	s = sl;
2865	+	boolean c = s.red; s.red = p.red; p.red = c; // swap colors
2866	+	TreeNode<K,V> sr = s.right;
2867	+	TreeNode<K,V> pp = p.parent;
2868	+	if (s == pr) { // p was s's direct parent
2869	+	p.parent = s;
2870	+	s.right = p;
2871	+	}
2872	+	else {
2873	+	TreeNode<K,V> sp = s.parent;
2874	+	if ((p.parent = sp) != null) {
2875	+	if (s == sp.left)
2876	+	sp.left = p;
2877	+	else
2878	+	sp.right = p;
2879	+	}
2880	+	if ((s.right = pr) != null)
2881	+	pr.parent = s;
2882	+	}
2883	+	p.left = null;
2884	+	if ((p.right = sr) != null)
2885	+	sr.parent = p;
2886	+	if ((s.left = pl) != null)
2887	+	pl.parent = s;
2888	+	if ((s.parent = pp) == null)
2889	+	r = s;
2890	+	else if (p == pp.left)
2891	+	pp.left = s;
2892	+	else
2893	+	pp.right = s;
2894	+	if (sr != null)
2895	+	replacement = sr;
2896	+	else
2897	+	replacement = p;
2898	+	}
2899	+	else if (pl != null)
2900	+	replacement = pl;
2901	+	else if (pr != null)
2902	+	replacement = pr;
2903	+	else
2904	+	replacement = p;
2905	+	if (replacement != p) {
2906	+	TreeNode<K,V> pp = replacement.parent = p.parent;
2907	+	if (pp == null)
2908	+	r = replacement;
2909	+	else if (p == pp.left)
2910	+	pp.left = replacement;
2911	+	else
2912	+	pp.right = replacement;
2913	+	p.left = p.right = p.parent = null;
2914	+	}
2915
2916	<	public ValueIterator<K,V> clone() {
2917	<	if (last != null || (next != null && nextVal == null))
2916	>	root = (p.red) ? r : balanceDeletion(r, replacement);
2917	>
2918	>	if (p == replacement) {  // detach pointers
2919	>	TreeNode<K,V> pp;
2920	>	if ((pp = p.parent) != null) {
2921	>	if (p == pp.left)
2922	>	pp.left = null;
2923	>	else if (p == pp.right)
2924	>	pp.right = null;
2925	>	p.parent = null;
2926	>	}
2927	>	}
2928	>	} finally {
2929	>	unlockRoot();
2930	>	}
2931	>	assert checkInvariants(root);
2932	>	return false;
2933	>	}
2934	>
2935	>	/* ------------------------------------------------------------ */
2936	>	// Red-black tree methods, all adapted from CLR
2937	>
2938	>	static <K,V> TreeNode<K,V> rotateLeft(TreeNode<K,V> root,
2939	>	TreeNode<K,V> p) {
2940	>	TreeNode<K,V> r, pp, rl;
2941	>	if (p != null && (r = p.right) != null) {
2942	>	if ((rl = p.right = r.left) != null)
2943	>	rl.parent = p;
2944	>	if ((pp = r.parent = p.parent) == null)
2945	>	(root = r).red = false;
2946	>	else if (pp.left == p)
2947	>	pp.left = r;
2948	>	else
2949	>	pp.right = r;
2950	>	r.left = p;
2951	>	p.parent = r;
2952	>	}
2953	>	return root;
2954	>	}
2955	>
2956	>	static <K,V> TreeNode<K,V> rotateRight(TreeNode<K,V> root,
2957	>	TreeNode<K,V> p) {
2958	>	TreeNode<K,V> l, pp, lr;
2959	>	if (p != null && (l = p.left) != null) {
2960	>	if ((lr = p.left = l.right) != null)
2961	>	lr.parent = p;
2962	>	if ((pp = l.parent = p.parent) == null)
2963	>	(root = l).red = false;
2964	>	else if (pp.right == p)
2965	>	pp.right = l;
2966	>	else
2967	>	pp.left = l;
2968	>	l.right = p;
2969	>	p.parent = l;
2970	>	}
2971	>	return root;
2972	>	}
2973	>
2974	>	static <K,V> TreeNode<K,V> balanceInsertion(TreeNode<K,V> root,
2975	>	TreeNode<K,V> x) {
2976	>	x.red = true;
2977	>	for (TreeNode<K,V> xp, xpp, xppl, xppr;;) {
2978	>	if ((xp = x.parent) == null) {
2979	>	x.red = false;
2980	>	return x;
2981	>	}
2982	>	else if (!xp.red || (xpp = xp.parent) == null)
2983	>	return root;
2984	>	if (xp == (xppl = xpp.left)) {
2985	>	if ((xppr = xpp.right) != null && xppr.red) {
2986	>	xppr.red = false;
2987	>	xp.red = false;
2988	>	xpp.red = true;
2989	>	x = xpp;
2990	>	}
2991	>	else {
2992	>	if (x == xp.right) {
2993	>	root = rotateLeft(root, x = xp);
2994	>	xpp = (xp = x.parent) == null ? null : xp.parent;
2995	>	}
2996	>	if (xp != null) {
2997	>	xp.red = false;
2998	>	if (xpp != null) {
2999	>	xpp.red = true;
3000	>	root = rotateRight(root, xpp);
3001	>	}
3002	>	}
3003	>	}
3004	>	}
3005	>	else {
3006	>	if (xppl != null && xppl.red) {
3007	>	xppl.red = false;
3008	>	xp.red = false;
3009	>	xpp.red = true;
3010	>	x = xpp;
3011	>	}
3012	>	else {
3013	>	if (x == xp.left) {
3014	>	root = rotateRight(root, x = xp);
3015	>	xpp = (xp = x.parent) == null ? null : xp.parent;
3016	>	}
3017	>	if (xp != null) {
3018	>	xp.red = false;
3019	>	if (xpp != null) {
3020	>	xpp.red = true;
3021	>	root = rotateLeft(root, xpp);
3022	>	}
3023	>	}
3024	>	}
3025	>	}
3026	>	}
3027	>	}
3028	>
3029	>	static <K,V> TreeNode<K,V> balanceDeletion(TreeNode<K,V> root,
3030	>	TreeNode<K,V> x) {
3031	>	for (TreeNode<K,V> xp, xpl, xpr;;) {
3032	>	if (x == null || x == root)
3033	>	return root;
3034	>	else if ((xp = x.parent) == null) {
3035	>	x.red = false;
3036	>	return x;
3037	>	}
3038	>	else if (x.red) {
3039	>	x.red = false;
3040	>	return root;
3041	>	}
3042	>	else if ((xpl = xp.left) == x) {
3043	>	if ((xpr = xp.right) != null && xpr.red) {
3044	>	xpr.red = false;
3045	>	xp.red = true;
3046	>	root = rotateLeft(root, xp);
3047	>	xpr = (xp = x.parent) == null ? null : xp.right;
3048	>	}
3049	>	if (xpr == null)
3050	>	x = xp;
3051	>	else {
3052	>	TreeNode<K,V> sl = xpr.left, sr = xpr.right;
3053	>	if ((sr == null || !sr.red) &&
3054	>	(sl == null || !sl.red)) {
3055	>	xpr.red = true;
3056	>	x = xp;
3057	>	}
3058	>	else {
3059	>	if (sr == null || !sr.red) {
3060	>	if (sl != null)
3061	>	sl.red = false;
3062	>	xpr.red = true;
3063	>	root = rotateRight(root, xpr);
3064	>	xpr = (xp = x.parent) == null ?
3065	>	null : xp.right;
3066	>	}
3067	>	if (xpr != null) {
3068	>	xpr.red = (xp == null) ? false : xp.red;
3069	>	if ((sr = xpr.right) != null)
3070	>	sr.red = false;
3071	>	}
3072	>	if (xp != null) {
3073	>	xp.red = false;
3074	>	root = rotateLeft(root, xp);
3075	>	}
3076	>	x = root;
3077	>	}
3078	>	}
3079	>	}
3080	>	else { // symmetric
3081	>	if (xpl != null && xpl.red) {
3082	>	xpl.red = false;
3083	>	xp.red = true;
3084	>	root = rotateRight(root, xp);
3085	>	xpl = (xp = x.parent) == null ? null : xp.left;
3086	>	}
3087	>	if (xpl == null)
3088	>	x = xp;
3089	>	else {
3090	>	TreeNode<K,V> sl = xpl.left, sr = xpl.right;
3091	>	if ((sl == null || !sl.red) &&
3092	>	(sr == null || !sr.red)) {
3093	>	xpl.red = true;
3094	>	x = xp;
3095	>	}
3096	>	else {
3097	>	if (sl == null || !sl.red) {
3098	>	if (sr != null)
3099	>	sr.red = false;
3100	>	xpl.red = true;
3101	>	root = rotateLeft(root, xpl);
3102	>	xpl = (xp = x.parent) == null ?
3103	>	null : xp.left;
3104	>	}
3105	>	if (xpl != null) {
3106	>	xpl.red = (xp == null) ? false : xp.red;
3107	>	if ((sl = xpl.left) != null)
3108	>	sl.red = false;
3109	>	}
3110	>	if (xp != null) {
3111	>	xp.red = false;
3112	>	root = rotateRight(root, xp);
3113	>	}
3114	>	x = root;
3115	>	}
3116	>	}
3117	>	}
3118	>	}
3119	>	}
3120	>
3121	>	/**
3122	>	* Recursive invariant check
3123	>	*/
3124	>	static <K,V> boolean checkInvariants(TreeNode<K,V> t) {
3125	>	TreeNode<K,V> tp = t.parent, tl = t.left, tr = t.right,
3126	>	tb = t.prev, tn = (TreeNode<K,V>)t.next;
3127	>	if (tb != null && tb.next != t)
3128	>	return false;
3129	>	if (tn != null && tn.prev != t)
3130	>	return false;
3131	>	if (tp != null && t != tp.left && t != tp.right)
3132	>	return false;
3133	>	if (tl != null && (tl.parent != t || tl.hash > t.hash))
3134	>	return false;
3135	>	if (tr != null && (tr.parent != t || tr.hash < t.hash))
3136	>	return false;
3137	>	if (t.red && tl != null && tl.red && tr != null && tr.red)
3138	>	return false;
3139	>	if (tl != null && !checkInvariants(tl))
3140	>	return false;
3141	>	if (tr != null && !checkInvariants(tr))
3142	>	return false;
3143	>	return true;
3144	>	}
3145	>
3146	>	private static final sun.misc.Unsafe U;
3147	>	private static final long LOCKSTATE;
3148	>	static {
3149	>	try {
3150	>	U = getUnsafe();
3151	>	Class<?> k = TreeBin.class;
3152	>	LOCKSTATE = U.objectFieldOffset
3153	>	(k.getDeclaredField("lockState"));
3154	>	} catch (Exception e) {
3155	>	throw new Error(e);
3156	>	}
3157	>	}
3158	>	}
3159	>
3160	>	/* ----------------Table Traversal -------------- */
3161	>
3162	>	/**
3163	>	* Records the table, its length, and current traversal index for a
3164	>	* traverser that must process a region of a forwarded table before
3165	>	* proceeding with current table.
3166	>	*/
3167	>	static final class TableStack<K,V> {
3168	>	int length;
3169	>	int index;
3170	>	Node<K,V>[] tab;
3171	>	TableStack<K,V> next;
3172	>	}
3173	>
3174	>	/**
3175	>	* Encapsulates traversal for methods such as containsValue; also
3176	>	* serves as a base class for other iterators and spliterators.
3177	>	*
3178	>	* Method advance visits once each still-valid node that was
3179	>	* reachable upon iterator construction. It might miss some that
3180	>	* were added to a bin after the bin was visited, which is OK wrt
3181	>	* consistency guarantees. Maintaining this property in the face
3182	>	* of possible ongoing resizes requires a fair amount of
3183	>	* bookkeeping state that is difficult to optimize away amidst
3184	>	* volatile accesses.  Even so, traversal maintains reasonable
3185	>	* throughput.
3186	>	*
3187	>	* Normally, iteration proceeds bin-by-bin traversing lists.
3188	>	* However, if the table has been resized, then all future steps
3189	>	* must traverse both the bin at the current index as well as at
3190	>	* (index + baseSize); and so on for further resizings. To
3191	>	* paranoically cope with potential sharing by users of iterators
3192	>	* across threads, iteration terminates if a bounds checks fails
3193	>	* for a table read.
3194	>	*/
3195	>	static class Traverser<K,V> {
3196	>	Node<K,V>[] tab;        // current table; updated if resized
3197	>	Node<K,V> next;         // the next entry to use
3198	>	TableStack<K,V> stack, spare; // to save/restore on ForwardingNodes
3199	>	int index;              // index of bin to use next
3200	>	int baseIndex;          // current index of initial table
3201	>	int baseLimit;          // index bound for initial table
3202	>	final int baseSize;     // initial table size
3203	>
3204	>	Traverser(Node<K,V>[] tab, int size, int index, int limit) {
3205	>	this.tab = tab;
3206	>	this.baseSize = size;
3207	>	this.baseIndex = this.index = index;
3208	>	this.baseLimit = limit;
3209	>	this.next = null;
3210	>	}
3211	>
3212	>	/**
3213	>	* Advances if possible, returning next valid node, or null if none.
3214	>	*/
3215	>	final Node<K,V> advance() {
3216	>	Node<K,V> e;
3217	>	if ((e = next) != null)
3218	>	e = e.next;
3219	>	for (;;) {
3220	>	Node<K,V>[] t; int i, n;  // must use locals in checks
3221	>	if (e != null)
3222	>	return next = e;
3223	>	if (baseIndex >= baseLimit || (t = tab) == null ||
3224	>	(n = t.length) <= (i = index) || i < 0)
3225	>	return next = null;
3226	>	if ((e = tabAt(t, i)) != null && e.hash < 0) {
3227	>	if (e instanceof ForwardingNode) {
3228	>	tab = ((ForwardingNode<K,V>)e).nextTable;
3229	>	e = null;
3230	>	pushState(t, i, n);
3231	>	continue;
3232	>	}
3233	>	else if (e instanceof TreeBin)
3234	>	e = ((TreeBin<K,V>)e).first;
3235	>	else
3236	>	e = null;
3237	>	}
3238	>	if (stack != null)
3239	>	recoverState(n);
3240	>	else if ((index = i + baseSize) >= n)
3241	>	index = ++baseIndex; // visit upper slots if present
3242	>	}
3243	>	}
3244	>
3245	>	/**
3246	>	* Saves traversal state upon encountering a forwarding node.
3247	>	*/
3248	>	private void pushState(Node<K,V>[] t, int i, int n) {
3249	>	TableStack<K,V> s = spare;  // reuse if possible
3250	>	if (s != null)
3251	>	spare = s.next;
3252	>	else
3253	>	s = new TableStack<K,V>();
3254	>	s.tab = t;
3255	>	s.length = n;
3256	>	s.index = i;
3257	>	s.next = stack;
3258	>	stack = s;
3259	>	}
3260	>
3261	>	/**
3262	>	* Possibly pops traversal state.
3263	>	*
3264	>	* @param n length of current table
3265	>	*/
3266	>	private void recoverState(int n) {
3267	>	TableStack<K,V> s; int len;
3268	>	while ((s = stack) != null && (index += (len = s.length)) >= n) {
3269	>	n = len;
3270	>	index = s.index;
3271	>	tab = s.tab;
3272	>	s.tab = null;
3273	>	TableStack<K,V> next = s.next;
3274	>	s.next = spare; // save for reuse
3275	>	stack = next;
3276	>	spare = s;
3277	>	}
3278	>	if (s == null && (index += baseSize) >= n)
3279	>	index = ++baseIndex;
3280	>	}
3281	>	}
3282	>
3283	>	/**
3284	>	* Base of key, value, and entry Iterators. Adds fields to
3285	>	* Traverser to support iterator.remove.
3286	>	*/
3287	>	static class BaseIterator<K,V> extends Traverser<K,V> {
3288	>	final ConcurrentHashMapV8<K,V> map;
3289	>	Node<K,V> lastReturned;
3290	>	BaseIterator(Node<K,V>[] tab, int size, int index, int limit,
3291	>	ConcurrentHashMapV8<K,V> map) {
3292	>	super(tab, size, index, limit);
3293	>	this.map = map;
3294	>	advance();
3295	>	}
3296	>
3297	>	public final boolean hasNext() { return next != null; }
3298	>	public final boolean hasMoreElements() { return next != null; }
3299	>
3300	>	public final void remove() {
3301	>	Node<K,V> p;
3302	>	if ((p = lastReturned) == null)
3303		throw new IllegalStateException();
3304	<	return new ValueIterator<K,V>(this, false);
3304	>	lastReturned = null;
3305	>	map.replaceNode(p.key, null, null);
3306		}
3307	+	}
3308
3309	<	@SuppressWarnings("unchecked")
3310	<	public final V next() {
3311	<	Object v;
3312	<	if ((v = nextVal) == null && (v = advance()) == null)
3309	>	static final class KeyIterator<K,V> extends BaseIterator<K,V>
3310	>	implements Iterator<K>, Enumeration<K> {
3311	>	KeyIterator(Node<K,V>[] tab, int index, int size, int limit,
3312	>	ConcurrentHashMapV8<K,V> map) {
3313	>	super(tab, index, size, limit, map);
3314	>	}
3315	>
3316	>	public final K next() {
3317	>	Node<K,V> p;
3318	>	if ((p = next) == null)
3319		throw new NoSuchElementException();
3320	<	nextVal = null;
3321	<	return (V) v;
3320	>	K k = p.key;
3321	>	lastReturned = p;
3322	>	advance();
3323	>	return k;
3324		}
3325
3326	<	public final V nextElement() { return next(); }
3326	>	public final K nextElement() { return next(); }
3327		}
3328
3329	<	static final class EntryIterator<K,V> extends InternalIterator<K,V>
3330	<	implements Spliterator<Map.Entry<K,V>> {
3331	<	EntryIterator(ConcurrentHashMapV8<K, V> map) { super(map); }
3332	<	EntryIterator(InternalIterator<K,V> it, boolean split) {
3333	<	super(it, split);
3329	>	static final class ValueIterator<K,V> extends BaseIterator<K,V>
3330	>	implements Iterator<V>, Enumeration<V> {
3331	>	ValueIterator(Node<K,V>[] tab, int index, int size, int limit,
3332	>	ConcurrentHashMapV8<K,V> map) {
3333	>	super(tab, index, size, limit, map);
3334		}
3335	<	public EntryIterator<K,V> split() {
3336	<	if (last != null || (next != null && nextVal == null))
3337	<	throw new IllegalStateException();
3338	<	return new EntryIterator<K,V>(this, true);
3335	>
3336	>	public final V next() {
3337	>	Node<K,V> p;
3338	>	if ((p = next) == null)
3339	>	throw new NoSuchElementException();
3340	>	V v = p.val;
3341	>	lastReturned = p;
3342	>	advance();
3343	>	return v;
3344		}
3345	<	public EntryIterator<K,V> clone() {
3346	<	if (last != null || (next != null && nextVal == null))
3347	<	throw new IllegalStateException();
3348	<	return new EntryIterator<K,V>(this, false);
3345	>
3346	>	public final V nextElement() { return next(); }
3347	>	}
3348	>
3349	>	static final class EntryIterator<K,V> extends BaseIterator<K,V>
3350	>	implements Iterator<Map.Entry<K,V>> {
3351	>	EntryIterator(Node<K,V>[] tab, int index, int size, int limit,
3352	>	ConcurrentHashMapV8<K,V> map) {
3353	>	super(tab, index, size, limit, map);
3354		}
3355
2904	–	@SuppressWarnings("unchecked")
3356		public final Map.Entry<K,V> next() {
3357	<	Object v;
3358	<	if ((v = nextVal) == null && (v = advance()) == null)
3357	>	Node<K,V> p;
3358	>	if ((p = next) == null)
3359		throw new NoSuchElementException();
3360	<	Object k = nextKey;
3361	<	nextVal = null;
3362	<	return new MapEntry<K,V>((K)k, (V)v, map);
3360	>	K k = p.key;
3361	>	V v = p.val;
3362	>	lastReturned = p;
3363	>	advance();
3364	>	return new MapEntry<K,V>(k, v, map);
3365		}
3366		}
3367
3368		/**
3369	<	* Exported Entry for iterators
3369	>	* Exported Entry for EntryIterator
3370		*/
3371	<	static final class MapEntry<K,V> implements Map.Entry<K, V> {
3371	>	static final class MapEntry<K,V> implements Map.Entry<K,V> {
3372		final K key; // non-null
3373		V val;       // non-null
3374	<	final ConcurrentHashMapV8<K, V> map;
3375	<	MapEntry(K key, V val, ConcurrentHashMapV8<K, V> map) {
3374	>	final ConcurrentHashMapV8<K,V> map;
3375	>	MapEntry(K key, V val, ConcurrentHashMapV8<K,V> map) {
3376		this.key = key;
3377		this.val = val;
3378		this.map = map;
3379		}
3380	<	public final K getKey()       { return key; }
3381	<	public final V getValue()     { return val; }
3382	<	public final int hashCode()   { return key.hashCode() ^ val.hashCode(); }
3383	<	public final String toString(){ return key + "=" + val; }
3380	>	public K getKey()        { return key; }
3381	>	public V getValue()      { return val; }
3382	>	public int hashCode()    { return key.hashCode() ^ val.hashCode(); }
3383	>	public String toString() { return key + "=" + val; }
3384
3385	<	public final boolean equals(Object o) {
3385	>	public boolean equals(Object o) {
3386		Object k, v; Map.Entry<?,?> e;
3387		return ((o instanceof Map.Entry) &&
3388		(k = (e = (Map.Entry<?,?>)o).getKey()) != null &&
#	Line 2943 | Line 3396 | public class ConcurrentHashMapV8<K, V>
3396		* value to return is somewhat arbitrary here. Since we do not
3397		* necessarily track asynchronous changes, the most recent
3398		* "previous" value could be different from what we return (or
3399	<	* could even have been removed in which case the put will
3399	>	* could even have been removed, in which case the put will
3400		* re-establish). We do not and cannot guarantee more.
3401		*/
3402	<	public final V setValue(V value) {
3402	>	public V setValue(V value) {
3403		if (value == null) throw new NullPointerException();
3404		V v = val;
3405		val = value;
#	Line 2955 | Line 3408 | public class ConcurrentHashMapV8<K, V>
3408		}
3409		}
3410
3411	+	static final class KeySpliterator<K,V> extends Traverser<K,V>
3412	+	implements ConcurrentHashMapSpliterator<K> {
3413	+	long est;               // size estimate
3414	+	KeySpliterator(Node<K,V>[] tab, int size, int index, int limit,
3415	+	long est) {
3416	+	super(tab, size, index, limit);
3417	+	this.est = est;
3418	+	}
3419	+
3420	+	public ConcurrentHashMapSpliterator<K> trySplit() {
3421	+	int i, f, h;
3422	+	return (h = ((i = baseIndex) + (f = baseLimit)) >>> 1) <= i ? null :
3423	+	new KeySpliterator<K,V>(tab, baseSize, baseLimit = h,
3424	+	f, est >>>= 1);
3425	+	}
3426	+
3427	+	public void forEachRemaining(Action<? super K> action) {
3428	+	if (action == null) throw new NullPointerException();
3429	+	for (Node<K,V> p; (p = advance()) != null;)
3430	+	action.apply(p.key);
3431	+	}
3432	+
3433	+	public boolean tryAdvance(Action<? super K> action) {
3434	+	if (action == null) throw new NullPointerException();
3435	+	Node<K,V> p;
3436	+	if ((p = advance()) == null)
3437	+	return false;
3438	+	action.apply(p.key);
3439	+	return true;
3440	+	}
3441	+
3442	+	public long estimateSize() { return est; }
3443	+
3444	+	}
3445	+
3446	+	static final class ValueSpliterator<K,V> extends Traverser<K,V>
3447	+	implements ConcurrentHashMapSpliterator<V> {
3448	+	long est;               // size estimate
3449	+	ValueSpliterator(Node<K,V>[] tab, int size, int index, int limit,
3450	+	long est) {
3451	+	super(tab, size, index, limit);
3452	+	this.est = est;
3453	+	}
3454	+
3455	+	public ConcurrentHashMapSpliterator<V> trySplit() {
3456	+	int i, f, h;
3457	+	return (h = ((i = baseIndex) + (f = baseLimit)) >>> 1) <= i ? null :
3458	+	new ValueSpliterator<K,V>(tab, baseSize, baseLimit = h,
3459	+	f, est >>>= 1);
3460	+	}
3461	+
3462	+	public void forEachRemaining(Action<? super V> action) {
3463	+	if (action == null) throw new NullPointerException();
3464	+	for (Node<K,V> p; (p = advance()) != null;)
3465	+	action.apply(p.val);
3466	+	}
3467	+
3468	+	public boolean tryAdvance(Action<? super V> action) {
3469	+	if (action == null) throw new NullPointerException();
3470	+	Node<K,V> p;
3471	+	if ((p = advance()) == null)
3472	+	return false;
3473	+	action.apply(p.val);
3474	+	return true;
3475	+	}
3476	+
3477	+	public long estimateSize() { return est; }
3478	+
3479	+	}
3480	+
3481	+	static final class EntrySpliterator<K,V> extends Traverser<K,V>
3482	+	implements ConcurrentHashMapSpliterator<Map.Entry<K,V>> {
3483	+	final ConcurrentHashMapV8<K,V> map; // To export MapEntry
3484	+	long est;               // size estimate
3485	+	EntrySpliterator(Node<K,V>[] tab, int size, int index, int limit,
3486	+	long est, ConcurrentHashMapV8<K,V> map) {
3487	+	super(tab, size, index, limit);
3488	+	this.map = map;
3489	+	this.est = est;
3490	+	}
3491	+
3492	+	public ConcurrentHashMapSpliterator<Map.Entry<K,V>> trySplit() {
3493	+	int i, f, h;
3494	+	return (h = ((i = baseIndex) + (f = baseLimit)) >>> 1) <= i ? null :
3495	+	new EntrySpliterator<K,V>(tab, baseSize, baseLimit = h,
3496	+	f, est >>>= 1, map);
3497	+	}
3498	+
3499	+	public void forEachRemaining(Action<? super Map.Entry<K,V>> action) {
3500	+	if (action == null) throw new NullPointerException();
3501	+	for (Node<K,V> p; (p = advance()) != null; )
3502	+	action.apply(new MapEntry<K,V>(p.key, p.val, map));
3503	+	}
3504	+
3505	+	public boolean tryAdvance(Action<? super Map.Entry<K,V>> action) {
3506	+	if (action == null) throw new NullPointerException();
3507	+	Node<K,V> p;
3508	+	if ((p = advance()) == null)
3509	+	return false;
3510	+	action.apply(new MapEntry<K,V>(p.key, p.val, map));
3511	+	return true;
3512	+	}
3513	+
3514	+	public long estimateSize() { return est; }
3515	+
3516	+	}
3517	+
3518	+	// Parallel bulk operations
3519	+
3520	+	/**
3521	+	* Computes initial batch value for bulk tasks. The returned value
3522	+	* is approximately exp2 of the number of times (minus one) to
3523	+	* split task by two before executing leaf action. This value is
3524	+	* faster to compute and more convenient to use as a guide to
3525	+	* splitting than is the depth, since it is used while dividing by
3526	+	* two anyway.
3527	+	*/
3528	+	final int batchFor(long b) {
3529	+	long n;
3530	+	if (b == Long.MAX_VALUE || (n = sumCount()) <= 1L || n < b)
3531	+	return 0;
3532	+	int sp = ForkJoinPool.getCommonPoolParallelism() << 2; // slack of 4
3533	+	return (b <= 0L || (n /= b) >= sp) ? sp : (int)n;
3534	+	}
3535	+
3536	+	/**
3537	+	* Performs the given action for each (key, value).
3538	+	*
3539	+	* @param parallelismThreshold the (estimated) number of elements
3540	+	* needed for this operation to be executed in parallel
3541	+	* @param action the action
3542	+	* @since 1.8
3543	+	*/
3544	+	public void forEach(long parallelismThreshold,
3545	+	BiAction<? super K,? super V> action) {
3546	+	if (action == null) throw new NullPointerException();
3547	+	new ForEachMappingTask<K,V>
3548	+	(null, batchFor(parallelismThreshold), 0, 0, table,
3549	+	action).invoke();
3550	+	}
3551	+
3552	+	/**
3553	+	* Performs the given action for each non-null transformation
3554	+	* of each (key, value).
3555	+	*
3556	+	* @param parallelismThreshold the (estimated) number of elements
3557	+	* needed for this operation to be executed in parallel
3558	+	* @param transformer a function returning the transformation
3559	+	* for an element, or null if there is no transformation (in
3560	+	* which case the action is not applied)
3561	+	* @param action the action
3562	+	* @since 1.8
3563	+	*/
3564	+	public <U> void forEach(long parallelismThreshold,
3565	+	BiFun<? super K, ? super V, ? extends U> transformer,
3566	+	Action<? super U> action) {
3567	+	if (transformer == null || action == null)
3568	+	throw new NullPointerException();
3569	+	new ForEachTransformedMappingTask<K,V,U>
3570	+	(null, batchFor(parallelismThreshold), 0, 0, table,
3571	+	transformer, action).invoke();
3572	+	}
3573	+
3574	+	/**
3575	+	* Returns a non-null result from applying the given search
3576	+	* function on each (key, value), or null if none.  Upon
3577	+	* success, further element processing is suppressed and the
3578	+	* results of any other parallel invocations of the search
3579	+	* function are ignored.
3580	+	*
3581	+	* @param parallelismThreshold the (estimated) number of elements
3582	+	* needed for this operation to be executed in parallel
3583	+	* @param searchFunction a function returning a non-null
3584	+	* result on success, else null
3585	+	* @return a non-null result from applying the given search
3586	+	* function on each (key, value), or null if none
3587	+	* @since 1.8
3588	+	*/
3589	+	public <U> U search(long parallelismThreshold,
3590	+	BiFun<? super K, ? super V, ? extends U> searchFunction) {
3591	+	if (searchFunction == null) throw new NullPointerException();
3592	+	return new SearchMappingsTask<K,V,U>
3593	+	(null, batchFor(parallelismThreshold), 0, 0, table,
3594	+	searchFunction, new AtomicReference<U>()).invoke();
3595	+	}
3596	+
3597	+	/**
3598	+	* Returns the result of accumulating the given transformation
3599	+	* of all (key, value) pairs using the given reducer to
3600	+	* combine values, or null if none.
3601	+	*
3602	+	* @param parallelismThreshold the (estimated) number of elements
3603	+	* needed for this operation to be executed in parallel
3604	+	* @param transformer a function returning the transformation
3605	+	* for an element, or null if there is no transformation (in
3606	+	* which case it is not combined)
3607	+	* @param reducer a commutative associative combining function
3608	+	* @return the result of accumulating the given transformation
3609	+	* of all (key, value) pairs
3610	+	* @since 1.8
3611	+	*/
3612	+	public <U> U reduce(long parallelismThreshold,
3613	+	BiFun<? super K, ? super V, ? extends U> transformer,
3614	+	BiFun<? super U, ? super U, ? extends U> reducer) {
3615	+	if (transformer == null || reducer == null)
3616	+	throw new NullPointerException();
3617	+	return new MapReduceMappingsTask<K,V,U>
3618	+	(null, batchFor(parallelismThreshold), 0, 0, table,
3619	+	null, transformer, reducer).invoke();
3620	+	}
3621	+
3622	+	/**
3623	+	* Returns the result of accumulating the given transformation
3624	+	* of all (key, value) pairs using the given reducer to
3625	+	* combine values, and the given basis as an identity value.
3626	+	*
3627	+	* @param parallelismThreshold the (estimated) number of elements
3628	+	* needed for this operation to be executed in parallel
3629	+	* @param transformer a function returning the transformation
3630	+	* for an element
3631	+	* @param basis the identity (initial default value) for the reduction
3632	+	* @param reducer a commutative associative combining function
3633	+	* @return the result of accumulating the given transformation
3634	+	* of all (key, value) pairs
3635	+	* @since 1.8
3636	+	*/
3637	+	public double reduceToDouble(long parallelismThreshold,
3638	+	ObjectByObjectToDouble<? super K, ? super V> transformer,
3639	+	double basis,
3640	+	DoubleByDoubleToDouble reducer) {
3641	+	if (transformer == null || reducer == null)
3642	+	throw new NullPointerException();
3643	+	return new MapReduceMappingsToDoubleTask<K,V>
3644	+	(null, batchFor(parallelismThreshold), 0, 0, table,
3645	+	null, transformer, basis, reducer).invoke();
3646	+	}
3647	+
3648	+	/**
3649	+	* Returns the result of accumulating the given transformation
3650	+	* of all (key, value) pairs using the given reducer to
3651	+	* combine values, and the given basis as an identity value.
3652	+	*
3653	+	* @param parallelismThreshold the (estimated) number of elements
3654	+	* needed for this operation to be executed in parallel
3655	+	* @param transformer a function returning the transformation
3656	+	* for an element
3657	+	* @param basis the identity (initial default value) for the reduction
3658	+	* @param reducer a commutative associative combining function
3659	+	* @return the result of accumulating the given transformation
3660	+	* of all (key, value) pairs
3661	+	* @since 1.8
3662	+	*/
3663	+	public long reduceToLong(long parallelismThreshold,
3664	+	ObjectByObjectToLong<? super K, ? super V> transformer,
3665	+	long basis,
3666	+	LongByLongToLong reducer) {
3667	+	if (transformer == null || reducer == null)
3668	+	throw new NullPointerException();
3669	+	return new MapReduceMappingsToLongTask<K,V>
3670	+	(null, batchFor(parallelismThreshold), 0, 0, table,
3671	+	null, transformer, basis, reducer).invoke();
3672	+	}
3673	+
3674	+	/**
3675	+	* Returns the result of accumulating the given transformation
3676	+	* of all (key, value) pairs using the given reducer to
3677	+	* combine values, and the given basis as an identity value.
3678	+	*
3679	+	* @param parallelismThreshold the (estimated) number of elements
3680	+	* needed for this operation to be executed in parallel
3681	+	* @param transformer a function returning the transformation
3682	+	* for an element
3683	+	* @param basis the identity (initial default value) for the reduction
3684	+	* @param reducer a commutative associative combining function
3685	+	* @return the result of accumulating the given transformation
3686	+	* of all (key, value) pairs
3687	+	* @since 1.8
3688	+	*/
3689	+	public int reduceToInt(long parallelismThreshold,
3690	+	ObjectByObjectToInt<? super K, ? super V> transformer,
3691	+	int basis,
3692	+	IntByIntToInt reducer) {
3693	+	if (transformer == null || reducer == null)
3694	+	throw new NullPointerException();
3695	+	return new MapReduceMappingsToIntTask<K,V>
3696	+	(null, batchFor(parallelismThreshold), 0, 0, table,
3697	+	null, transformer, basis, reducer).invoke();
3698	+	}
3699	+
3700	+	/**
3701	+	* Performs the given action for each key.
3702	+	*
3703	+	* @param parallelismThreshold the (estimated) number of elements
3704	+	* needed for this operation to be executed in parallel
3705	+	* @param action the action
3706	+	* @since 1.8
3707	+	*/
3708	+	public void forEachKey(long parallelismThreshold,
3709	+	Action<? super K> action) {
3710	+	if (action == null) throw new NullPointerException();
3711	+	new ForEachKeyTask<K,V>
3712	+	(null, batchFor(parallelismThreshold), 0, 0, table,
3713	+	action).invoke();
3714	+	}
3715	+
3716	+	/**
3717	+	* Performs the given action for each non-null transformation
3718	+	* of each key.
3719	+	*
3720	+	* @param parallelismThreshold the (estimated) number of elements
3721	+	* needed for this operation to be executed in parallel
3722	+	* @param transformer a function returning the transformation
3723	+	* for an element, or null if there is no transformation (in
3724	+	* which case the action is not applied)
3725	+	* @param action the action
3726	+	* @since 1.8
3727	+	*/
3728	+	public <U> void forEachKey(long parallelismThreshold,
3729	+	Fun<? super K, ? extends U> transformer,
3730	+	Action<? super U> action) {
3731	+	if (transformer == null || action == null)
3732	+	throw new NullPointerException();
3733	+	new ForEachTransformedKeyTask<K,V,U>
3734	+	(null, batchFor(parallelismThreshold), 0, 0, table,
3735	+	transformer, action).invoke();
3736	+	}
3737	+
3738	+	/**
3739	+	* Returns a non-null result from applying the given search
3740	+	* function on each key, or null if none. Upon success,
3741	+	* further element processing is suppressed and the results of
3742	+	* any other parallel invocations of the search function are
3743	+	* ignored.
3744	+	*
3745	+	* @param parallelismThreshold the (estimated) number of elements
3746	+	* needed for this operation to be executed in parallel
3747	+	* @param searchFunction a function returning a non-null
3748	+	* result on success, else null
3749	+	* @return a non-null result from applying the given search
3750	+	* function on each key, or null if none
3751	+	* @since 1.8
3752	+	*/
3753	+	public <U> U searchKeys(long parallelismThreshold,
3754	+	Fun<? super K, ? extends U> searchFunction) {
3755	+	if (searchFunction == null) throw new NullPointerException();
3756	+	return new SearchKeysTask<K,V,U>
3757	+	(null, batchFor(parallelismThreshold), 0, 0, table,
3758	+	searchFunction, new AtomicReference<U>()).invoke();
3759	+	}
3760	+
3761	+	/**
3762	+	* Returns the result of accumulating all keys using the given
3763	+	* reducer to combine values, or null if none.
3764	+	*
3765	+	* @param parallelismThreshold the (estimated) number of elements
3766	+	* needed for this operation to be executed in parallel
3767	+	* @param reducer a commutative associative combining function
3768	+	* @return the result of accumulating all keys using the given
3769	+	* reducer to combine values, or null if none
3770	+	* @since 1.8
3771	+	*/
3772	+	public K reduceKeys(long parallelismThreshold,
3773	+	BiFun<? super K, ? super K, ? extends K> reducer) {
3774	+	if (reducer == null) throw new NullPointerException();
3775	+	return new ReduceKeysTask<K,V>
3776	+	(null, batchFor(parallelismThreshold), 0, 0, table,
3777	+	null, reducer).invoke();
3778	+	}
3779	+
3780	+	/**
3781	+	* Returns the result of accumulating the given transformation
3782	+	* of all keys using the given reducer to combine values, or
3783	+	* null if none.
3784	+	*
3785	+	* @param parallelismThreshold the (estimated) number of elements
3786	+	* needed for this operation to be executed in parallel
3787	+	* @param transformer a function returning the transformation
3788	+	* for an element, or null if there is no transformation (in
3789	+	* which case it is not combined)
3790	+	* @param reducer a commutative associative combining function
3791	+	* @return the result of accumulating the given transformation
3792	+	* of all keys
3793	+	* @since 1.8
3794	+	*/
3795	+	public <U> U reduceKeys(long parallelismThreshold,
3796	+	Fun<? super K, ? extends U> transformer,
3797	+	BiFun<? super U, ? super U, ? extends U> reducer) {
3798	+	if (transformer == null || reducer == null)
3799	+	throw new NullPointerException();
3800	+	return new MapReduceKeysTask<K,V,U>
3801	+	(null, batchFor(parallelismThreshold), 0, 0, table,
3802	+	null, transformer, reducer).invoke();
3803	+	}
3804	+
3805	+	/**
3806	+	* Returns the result of accumulating the given transformation
3807	+	* of all keys using the given reducer to combine values, and
3808	+	* the given basis as an identity value.
3809	+	*
3810	+	* @param parallelismThreshold the (estimated) number of elements
3811	+	* needed for this operation to be executed in parallel
3812	+	* @param transformer a function returning the transformation
3813	+	* for an element
3814	+	* @param basis the identity (initial default value) for the reduction
3815	+	* @param reducer a commutative associative combining function
3816	+	* @return the result of accumulating the given transformation
3817	+	* of all keys
3818	+	* @since 1.8
3819	+	*/
3820	+	public double reduceKeysToDouble(long parallelismThreshold,
3821	+	ObjectToDouble<? super K> transformer,
3822	+	double basis,
3823	+	DoubleByDoubleToDouble reducer) {
3824	+	if (transformer == null || reducer == null)
3825	+	throw new NullPointerException();
3826	+	return new MapReduceKeysToDoubleTask<K,V>
3827	+	(null, batchFor(parallelismThreshold), 0, 0, table,
3828	+	null, transformer, basis, reducer).invoke();
3829	+	}
3830	+
3831	+	/**
3832	+	* Returns the result of accumulating the given transformation
3833	+	* of all keys using the given reducer to combine values, and
3834	+	* the given basis as an identity value.
3835	+	*
3836	+	* @param parallelismThreshold the (estimated) number of elements
3837	+	* needed for this operation to be executed in parallel
3838	+	* @param transformer a function returning the transformation
3839	+	* for an element
3840	+	* @param basis the identity (initial default value) for the reduction
3841	+	* @param reducer a commutative associative combining function
3842	+	* @return the result of accumulating the given transformation
3843	+	* of all keys
3844	+	* @since 1.8
3845	+	*/
3846	+	public long reduceKeysToLong(long parallelismThreshold,
3847	+	ObjectToLong<? super K> transformer,
3848	+	long basis,
3849	+	LongByLongToLong reducer) {
3850	+	if (transformer == null || reducer == null)
3851	+	throw new NullPointerException();
3852	+	return new MapReduceKeysToLongTask<K,V>
3853	+	(null, batchFor(parallelismThreshold), 0, 0, table,
3854	+	null, transformer, basis, reducer).invoke();
3855	+	}
3856	+
3857	+	/**
3858	+	* Returns the result of accumulating the given transformation
3859	+	* of all keys using the given reducer to combine values, and
3860	+	* the given basis as an identity value.
3861	+	*
3862	+	* @param parallelismThreshold the (estimated) number of elements
3863	+	* needed for this operation to be executed in parallel
3864	+	* @param transformer a function returning the transformation
3865	+	* for an element
3866	+	* @param basis the identity (initial default value) for the reduction
3867	+	* @param reducer a commutative associative combining function
3868	+	* @return the result of accumulating the given transformation
3869	+	* of all keys
3870	+	* @since 1.8
3871	+	*/
3872	+	public int reduceKeysToInt(long parallelismThreshold,
3873	+	ObjectToInt<? super K> transformer,
3874	+	int basis,
3875	+	IntByIntToInt reducer) {
3876	+	if (transformer == null || reducer == null)
3877	+	throw new NullPointerException();
3878	+	return new MapReduceKeysToIntTask<K,V>
3879	+	(null, batchFor(parallelismThreshold), 0, 0, table,
3880	+	null, transformer, basis, reducer).invoke();
3881	+	}
3882	+
3883	+	/**
3884	+	* Performs the given action for each value.
3885	+	*
3886	+	* @param parallelismThreshold the (estimated) number of elements
3887	+	* needed for this operation to be executed in parallel
3888	+	* @param action the action
3889	+	* @since 1.8
3890	+	*/
3891	+	public void forEachValue(long parallelismThreshold,
3892	+	Action<? super V> action) {
3893	+	if (action == null)
3894	+	throw new NullPointerException();
3895	+	new ForEachValueTask<K,V>
3896	+	(null, batchFor(parallelismThreshold), 0, 0, table,
3897	+	action).invoke();
3898	+	}
3899	+
3900	+	/**
3901	+	* Performs the given action for each non-null transformation
3902	+	* of each value.
3903	+	*
3904	+	* @param parallelismThreshold the (estimated) number of elements
3905	+	* needed for this operation to be executed in parallel
3906	+	* @param transformer a function returning the transformation
3907	+	* for an element, or null if there is no transformation (in
3908	+	* which case the action is not applied)
3909	+	* @param action the action
3910	+	* @since 1.8
3911	+	*/
3912	+	public <U> void forEachValue(long parallelismThreshold,
3913	+	Fun<? super V, ? extends U> transformer,
3914	+	Action<? super U> action) {
3915	+	if (transformer == null || action == null)
3916	+	throw new NullPointerException();
3917	+	new ForEachTransformedValueTask<K,V,U>
3918	+	(null, batchFor(parallelismThreshold), 0, 0, table,
3919	+	transformer, action).invoke();
3920	+	}
3921	+
3922	+	/**
3923	+	* Returns a non-null result from applying the given search
3924	+	* function on each value, or null if none.  Upon success,
3925	+	* further element processing is suppressed and the results of
3926	+	* any other parallel invocations of the search function are
3927	+	* ignored.
3928	+	*
3929	+	* @param parallelismThreshold the (estimated) number of elements
3930	+	* needed for this operation to be executed in parallel
3931	+	* @param searchFunction a function returning a non-null
3932	+	* result on success, else null
3933	+	* @return a non-null result from applying the given search
3934	+	* function on each value, or null if none
3935	+	* @since 1.8
3936	+	*/
3937	+	public <U> U searchValues(long parallelismThreshold,
3938	+	Fun<? super V, ? extends U> searchFunction) {
3939	+	if (searchFunction == null) throw new NullPointerException();
3940	+	return new SearchValuesTask<K,V,U>
3941	+	(null, batchFor(parallelismThreshold), 0, 0, table,
3942	+	searchFunction, new AtomicReference<U>()).invoke();
3943	+	}
3944	+
3945	+	/**
3946	+	* Returns the result of accumulating all values using the
3947	+	* given reducer to combine values, or null if none.
3948	+	*
3949	+	* @param parallelismThreshold the (estimated) number of elements
3950	+	* needed for this operation to be executed in parallel
3951	+	* @param reducer a commutative associative combining function
3952	+	* @return the result of accumulating all values
3953	+	* @since 1.8
3954	+	*/
3955	+	public V reduceValues(long parallelismThreshold,
3956	+	BiFun<? super V, ? super V, ? extends V> reducer) {
3957	+	if (reducer == null) throw new NullPointerException();
3958	+	return new ReduceValuesTask<K,V>
3959	+	(null, batchFor(parallelismThreshold), 0, 0, table,
3960	+	null, reducer).invoke();
3961	+	}
3962	+
3963	+	/**
3964	+	* Returns the result of accumulating the given transformation
3965	+	* of all values using the given reducer to combine values, or
3966	+	* null if none.
3967	+	*
3968	+	* @param parallelismThreshold the (estimated) number of elements
3969	+	* needed for this operation to be executed in parallel
3970	+	* @param transformer a function returning the transformation
3971	+	* for an element, or null if there is no transformation (in
3972	+	* which case it is not combined)
3973	+	* @param reducer a commutative associative combining function
3974	+	* @return the result of accumulating the given transformation
3975	+	* of all values
3976	+	* @since 1.8
3977	+	*/
3978	+	public <U> U reduceValues(long parallelismThreshold,
3979	+	Fun<? super V, ? extends U> transformer,
3980	+	BiFun<? super U, ? super U, ? extends U> reducer) {
3981	+	if (transformer == null || reducer == null)
3982	+	throw new NullPointerException();
3983	+	return new MapReduceValuesTask<K,V,U>
3984	+	(null, batchFor(parallelismThreshold), 0, 0, table,
3985	+	null, transformer, reducer).invoke();
3986	+	}
3987	+
3988	+	/**
3989	+	* Returns the result of accumulating the given transformation
3990	+	* of all values using the given reducer to combine values,
3991	+	* and the given basis as an identity value.
3992	+	*
3993	+	* @param parallelismThreshold the (estimated) number of elements
3994	+	* needed for this operation to be executed in parallel
3995	+	* @param transformer a function returning the transformation
3996	+	* for an element
3997	+	* @param basis the identity (initial default value) for the reduction
3998	+	* @param reducer a commutative associative combining function
3999	+	* @return the result of accumulating the given transformation
4000	+	* of all values
4001	+	* @since 1.8
4002	+	*/
4003	+	public double reduceValuesToDouble(long parallelismThreshold,
4004	+	ObjectToDouble<? super V> transformer,
4005	+	double basis,
4006	+	DoubleByDoubleToDouble reducer) {
4007	+	if (transformer == null || reducer == null)
4008	+	throw new NullPointerException();
4009	+	return new MapReduceValuesToDoubleTask<K,V>
4010	+	(null, batchFor(parallelismThreshold), 0, 0, table,
4011	+	null, transformer, basis, reducer).invoke();
4012	+	}
4013	+
4014	+	/**
4015	+	* Returns the result of accumulating the given transformation
4016	+	* of all values using the given reducer to combine values,
4017	+	* and the given basis as an identity value.
4018	+	*
4019	+	* @param parallelismThreshold the (estimated) number of elements
4020	+	* needed for this operation to be executed in parallel
4021	+	* @param transformer a function returning the transformation
4022	+	* for an element
4023	+	* @param basis the identity (initial default value) for the reduction
4024	+	* @param reducer a commutative associative combining function
4025	+	* @return the result of accumulating the given transformation
4026	+	* of all values
4027	+	* @since 1.8
4028	+	*/
4029	+	public long reduceValuesToLong(long parallelismThreshold,
4030	+	ObjectToLong<? super V> transformer,
4031	+	long basis,
4032	+	LongByLongToLong reducer) {
4033	+	if (transformer == null || reducer == null)
4034	+	throw new NullPointerException();
4035	+	return new MapReduceValuesToLongTask<K,V>
4036	+	(null, batchFor(parallelismThreshold), 0, 0, table,
4037	+	null, transformer, basis, reducer).invoke();
4038	+	}
4039	+
4040	+	/**
4041	+	* Returns the result of accumulating the given transformation
4042	+	* of all values using the given reducer to combine values,
4043	+	* and the given basis as an identity value.
4044	+	*
4045	+	* @param parallelismThreshold the (estimated) number of elements
4046	+	* needed for this operation to be executed in parallel
4047	+	* @param transformer a function returning the transformation
4048	+	* for an element
4049	+	* @param basis the identity (initial default value) for the reduction
4050	+	* @param reducer a commutative associative combining function
4051	+	* @return the result of accumulating the given transformation
4052	+	* of all values
4053	+	* @since 1.8
4054	+	*/
4055	+	public int reduceValuesToInt(long parallelismThreshold,
4056	+	ObjectToInt<? super V> transformer,
4057	+	int basis,
4058	+	IntByIntToInt reducer) {
4059	+	if (transformer == null || reducer == null)
4060	+	throw new NullPointerException();
4061	+	return new MapReduceValuesToIntTask<K,V>
4062	+	(null, batchFor(parallelismThreshold), 0, 0, table,
4063	+	null, transformer, basis, reducer).invoke();
4064	+	}
4065	+
4066	+	/**
4067	+	* Performs the given action for each entry.
4068	+	*
4069	+	* @param parallelismThreshold the (estimated) number of elements
4070	+	* needed for this operation to be executed in parallel
4071	+	* @param action the action
4072	+	* @since 1.8
4073	+	*/
4074	+	public void forEachEntry(long parallelismThreshold,
4075	+	Action<? super Map.Entry<K,V>> action) {
4076	+	if (action == null) throw new NullPointerException();
4077	+	new ForEachEntryTask<K,V>(null, batchFor(parallelismThreshold), 0, 0, table,
4078	+	action).invoke();
4079	+	}
4080	+
4081	+	/**
4082	+	* Performs the given action for each non-null transformation
4083	+	* of each entry.
4084	+	*
4085	+	* @param parallelismThreshold the (estimated) number of elements
4086	+	* needed for this operation to be executed in parallel
4087	+	* @param transformer a function returning the transformation
4088	+	* for an element, or null if there is no transformation (in
4089	+	* which case the action is not applied)
4090	+	* @param action the action
4091	+	* @since 1.8
4092	+	*/
4093	+	public <U> void forEachEntry(long parallelismThreshold,
4094	+	Fun<Map.Entry<K,V>, ? extends U> transformer,
4095	+	Action<? super U> action) {
4096	+	if (transformer == null || action == null)
4097	+	throw new NullPointerException();
4098	+	new ForEachTransformedEntryTask<K,V,U>
4099	+	(null, batchFor(parallelismThreshold), 0, 0, table,
4100	+	transformer, action).invoke();
4101	+	}
4102	+
4103	+	/**
4104	+	* Returns a non-null result from applying the given search
4105	+	* function on each entry, or null if none.  Upon success,
4106	+	* further element processing is suppressed and the results of
4107	+	* any other parallel invocations of the search function are
4108	+	* ignored.
4109	+	*
4110	+	* @param parallelismThreshold the (estimated) number of elements
4111	+	* needed for this operation to be executed in parallel
4112	+	* @param searchFunction a function returning a non-null
4113	+	* result on success, else null
4114	+	* @return a non-null result from applying the given search
4115	+	* function on each entry, or null if none
4116	+	* @since 1.8
4117	+	*/
4118	+	public <U> U searchEntries(long parallelismThreshold,
4119	+	Fun<Map.Entry<K,V>, ? extends U> searchFunction) {
4120	+	if (searchFunction == null) throw new NullPointerException();
4121	+	return new SearchEntriesTask<K,V,U>
4122	+	(null, batchFor(parallelismThreshold), 0, 0, table,
4123	+	searchFunction, new AtomicReference<U>()).invoke();
4124	+	}
4125	+
4126	+	/**
4127	+	* Returns the result of accumulating all entries using the
4128	+	* given reducer to combine values, or null if none.
4129	+	*
4130	+	* @param parallelismThreshold the (estimated) number of elements
4131	+	* needed for this operation to be executed in parallel
4132	+	* @param reducer a commutative associative combining function
4133	+	* @return the result of accumulating all entries
4134	+	* @since 1.8
4135	+	*/
4136	+	public Map.Entry<K,V> reduceEntries(long parallelismThreshold,
4137	+	BiFun<Map.Entry<K,V>, Map.Entry<K,V>, ? extends Map.Entry<K,V>> reducer) {
4138	+	if (reducer == null) throw new NullPointerException();
4139	+	return new ReduceEntriesTask<K,V>
4140	+	(null, batchFor(parallelismThreshold), 0, 0, table,
4141	+	null, reducer).invoke();
4142	+	}
4143	+
4144	+	/**
4145	+	* Returns the result of accumulating the given transformation
4146	+	* of all entries using the given reducer to combine values,
4147	+	* or null if none.
4148	+	*
4149	+	* @param parallelismThreshold the (estimated) number of elements
4150	+	* needed for this operation to be executed in parallel
4151	+	* @param transformer a function returning the transformation
4152	+	* for an element, or null if there is no transformation (in
4153	+	* which case it is not combined)
4154	+	* @param reducer a commutative associative combining function
4155	+	* @return the result of accumulating the given transformation
4156	+	* of all entries
4157	+	* @since 1.8
4158	+	*/
4159	+	public <U> U reduceEntries(long parallelismThreshold,
4160	+	Fun<Map.Entry<K,V>, ? extends U> transformer,
4161	+	BiFun<? super U, ? super U, ? extends U> reducer) {
4162	+	if (transformer == null || reducer == null)
4163	+	throw new NullPointerException();
4164	+	return new MapReduceEntriesTask<K,V,U>
4165	+	(null, batchFor(parallelismThreshold), 0, 0, table,
4166	+	null, transformer, reducer).invoke();
4167	+	}
4168	+
4169	+	/**
4170	+	* Returns the result of accumulating the given transformation
4171	+	* of all entries using the given reducer to combine values,
4172	+	* and the given basis as an identity value.
4173	+	*
4174	+	* @param parallelismThreshold the (estimated) number of elements
4175	+	* needed for this operation to be executed in parallel
4176	+	* @param transformer a function returning the transformation
4177	+	* for an element
4178	+	* @param basis the identity (initial default value) for the reduction
4179	+	* @param reducer a commutative associative combining function
4180	+	* @return the result of accumulating the given transformation
4181	+	* of all entries
4182	+	* @since 1.8
4183	+	*/
4184	+	public double reduceEntriesToDouble(long parallelismThreshold,
4185	+	ObjectToDouble<Map.Entry<K,V>> transformer,
4186	+	double basis,
4187	+	DoubleByDoubleToDouble reducer) {
4188	+	if (transformer == null || reducer == null)
4189	+	throw new NullPointerException();
4190	+	return new MapReduceEntriesToDoubleTask<K,V>
4191	+	(null, batchFor(parallelismThreshold), 0, 0, table,
4192	+	null, transformer, basis, reducer).invoke();
4193	+	}
4194	+
4195	+	/**
4196	+	* Returns the result of accumulating the given transformation
4197	+	* of all entries using the given reducer to combine values,
4198	+	* and the given basis as an identity value.
4199	+	*
4200	+	* @param parallelismThreshold the (estimated) number of elements
4201	+	* needed for this operation to be executed in parallel
4202	+	* @param transformer a function returning the transformation
4203	+	* for an element
4204	+	* @param basis the identity (initial default value) for the reduction
4205	+	* @param reducer a commutative associative combining function
4206	+	* @return the result of accumulating the given transformation
4207	+	* of all entries
4208	+	* @since 1.8
4209	+	*/
4210	+	public long reduceEntriesToLong(long parallelismThreshold,
4211	+	ObjectToLong<Map.Entry<K,V>> transformer,
4212	+	long basis,
4213	+	LongByLongToLong reducer) {
4214	+	if (transformer == null || reducer == null)
4215	+	throw new NullPointerException();
4216	+	return new MapReduceEntriesToLongTask<K,V>
4217	+	(null, batchFor(parallelismThreshold), 0, 0, table,
4218	+	null, transformer, basis, reducer).invoke();
4219	+	}
4220	+
4221	+	/**
4222	+	* Returns the result of accumulating the given transformation
4223	+	* of all entries using the given reducer to combine values,
4224	+	* and the given basis as an identity value.
4225	+	*
4226	+	* @param parallelismThreshold the (estimated) number of elements
4227	+	* needed for this operation to be executed in parallel
4228	+	* @param transformer a function returning the transformation
4229	+	* for an element
4230	+	* @param basis the identity (initial default value) for the reduction
4231	+	* @param reducer a commutative associative combining function
4232	+	* @return the result of accumulating the given transformation
4233	+	* of all entries
4234	+	* @since 1.8
4235	+	*/
4236	+	public int reduceEntriesToInt(long parallelismThreshold,
4237	+	ObjectToInt<Map.Entry<K,V>> transformer,
4238	+	int basis,
4239	+	IntByIntToInt reducer) {
4240	+	if (transformer == null || reducer == null)
4241	+	throw new NullPointerException();
4242	+	return new MapReduceEntriesToIntTask<K,V>
4243	+	(null, batchFor(parallelismThreshold), 0, 0, table,
4244	+	null, transformer, basis, reducer).invoke();
4245	+	}
4246	+
4247	+
4248		/* ----------------Views -------------- */
4249
4250		/**
4251		* Base class for views.
4252		*/
4253	<	static abstract class MapView<K, V> {
4254	<	final ConcurrentHashMapV8<K, V> map;
4255	<	MapView(ConcurrentHashMapV8<K, V> map)  { this.map = map; }
4256	<	public final int size()                 { return map.size(); }
4257	<	public final boolean isEmpty()          { return map.isEmpty(); }
4258	<	public final void clear()               { map.clear(); }
4253	>	abstract static class CollectionView<K,V,E>
4254	>	implements Collection<E>, java.io.Serializable {
4255	>	private static final long serialVersionUID = 7249069246763182397L;
4256	>	final ConcurrentHashMapV8<K,V> map;
4257	>	CollectionView(ConcurrentHashMapV8<K,V> map)  { this.map = map; }
4258	>
4259	>	/**
4260	>	* Returns the map backing this view.
4261	>	*
4262	>	* @return the map backing this view
4263	>	*/
4264	>	public ConcurrentHashMapV8<K,V> getMap() { return map; }
4265	>
4266	>	/**
4267	>	* Removes all of the elements from this view, by removing all
4268	>	* the mappings from the map backing this view.
4269	>	*/
4270	>	public final void clear()      { map.clear(); }
4271	>	public final int size()        { return map.size(); }
4272	>	public final boolean isEmpty() { return map.isEmpty(); }
4273
4274		// implementations below rely on concrete classes supplying these
4275	<	abstract public Iterator<?> iterator();
4276	<	abstract public boolean contains(Object o);
4277	<	abstract public boolean remove(Object o);
4275	>	// abstract methods
4276	>	/**
4277	>	* Returns a "weakly consistent" iterator that will never
4278	>	* throw {@link ConcurrentModificationException}, and
4279	>	* guarantees to traverse elements as they existed upon
4280	>	* construction of the iterator, and may (but is not
4281	>	* guaranteed to) reflect any modifications subsequent to
4282	>	* construction.
4283	>	*/
4284	>	public abstract Iterator<E> iterator();
4285	>	public abstract boolean contains(Object o);
4286	>	public abstract boolean remove(Object o);
4287
4288		private static final String oomeMsg = "Required array size too large";
4289
4290		public final Object[] toArray() {
4291	<	long sz = map.longSize();
4292	<	if (sz > (long)(MAX_ARRAY_SIZE))
4291	>	long sz = map.mappingCount();
4292	>	if (sz > MAX_ARRAY_SIZE)
4293		throw new OutOfMemoryError(oomeMsg);
4294		int n = (int)sz;
4295		Object[] r = new Object[n];
4296		int i = 0;
4297	<	Iterator<?> it = iterator();
2985	<	while (it.hasNext()) {
4297	>	for (E e : this) {
4298		if (i == n) {
4299		if (n >= MAX_ARRAY_SIZE)
4300		throw new OutOfMemoryError(oomeMsg);
#	Line 2992 | Line 4304 | public class ConcurrentHashMapV8<K, V>
4304		n += (n >>> 1) + 1;
4305		r = Arrays.copyOf(r, n);
4306		}
4307	<	r[i++] = it.next();
4307	>	r[i++] = e;
4308		}
4309		return (i == n) ? r : Arrays.copyOf(r, i);
4310		}
4311
4312		@SuppressWarnings("unchecked")
4313		public final <T> T[] toArray(T[] a) {
4314	<	long sz = map.longSize();
4315	<	if (sz > (long)(MAX_ARRAY_SIZE))
4314	>	long sz = map.mappingCount();
4315	>	if (sz > MAX_ARRAY_SIZE)
4316		throw new OutOfMemoryError(oomeMsg);
4317		int m = (int)sz;
4318		T[] r = (a.length >= m) ? a :
#	Line 3008 | Line 4320 | public class ConcurrentHashMapV8<K, V>
4320		.newInstance(a.getClass().getComponentType(), m);
4321		int n = r.length;
4322		int i = 0;
4323	<	Iterator<?> it = iterator();
3012	<	while (it.hasNext()) {
4323	>	for (E e : this) {
4324		if (i == n) {
4325		if (n >= MAX_ARRAY_SIZE)
4326		throw new OutOfMemoryError(oomeMsg);
#	Line 3019 | Line 4330 | public class ConcurrentHashMapV8<K, V>
4330		n += (n >>> 1) + 1;
4331		r = Arrays.copyOf(r, n);
4332		}
4333	<	r[i++] = (T)it.next();
4333	>	r[i++] = (T)e;
4334		}
4335		if (a == r && i < n) {
4336		r[i] = null; // null-terminate
#	Line 3028 | Line 4339 | public class ConcurrentHashMapV8<K, V>
4339		return (i == n) ? r : Arrays.copyOf(r, i);
4340		}
4341
4342	<	public final int hashCode() {
4343	<	int h = 0;
4344	<	for (Iterator<?> it = iterator(); it.hasNext();)
4345	<	h += it.next().hashCode();
4346	<	return h;
4347	<	}
4348	<
4342	>	/**
4343	>	* Returns a string representation of this collection.
4344	>	* The string representation consists of the string representations
4345	>	* of the collection's elements in the order they are returned by
4346	>	* its iterator, enclosed in square brackets ({@code "[]"}).
4347	>	* Adjacent elements are separated by the characters {@code ", "}
4348	>	* (comma and space).  Elements are converted to strings as by
4349	>	* {@link String#valueOf(Object)}.
4350	>	*
4351	>	* @return a string representation of this collection
4352	>	*/
4353		public final String toString() {
4354		StringBuilder sb = new StringBuilder();
4355		sb.append('[');
4356	<	Iterator<?> it = iterator();
4356	>	Iterator<E> it = iterator();
4357		if (it.hasNext()) {
4358		for (;;) {
4359		Object e = it.next();
#	Line 3053 | Line 4368 | public class ConcurrentHashMapV8<K, V>
4368
4369		public final boolean containsAll(Collection<?> c) {
4370		if (c != this) {
4371	<	for (Iterator<?> it = c.iterator(); it.hasNext();) {
3057	<	Object e = it.next();
4371	>	for (Object e : c) {
4372		if (e == null || !contains(e))
4373		return false;
4374		}
#	Line 3064 | Line 4378 | public class ConcurrentHashMapV8<K, V>
4378
4379		public final boolean removeAll(Collection<?> c) {
4380		boolean modified = false;
4381	<	for (Iterator<?> it = iterator(); it.hasNext();) {
4381	>	for (Iterator<E> it = iterator(); it.hasNext();) {
4382		if (c.contains(it.next())) {
4383		it.remove();
4384		modified = true;
#	Line 3075 | Line 4389 | public class ConcurrentHashMapV8<K, V>
4389
4390		public final boolean retainAll(Collection<?> c) {
4391		boolean modified = false;
4392	<	for (Iterator<?> it = iterator(); it.hasNext();) {
4392	>	for (Iterator<E> it = iterator(); it.hasNext();) {
4393		if (!c.contains(it.next())) {
4394		it.remove();
4395		modified = true;
#	Line 3086 | Line 4400 | public class ConcurrentHashMapV8<K, V>
4400
4401		}
4402
4403	<	static final class KeySet<K,V> extends MapView<K,V> implements Set<K> {
4404	<	KeySet(ConcurrentHashMapV8<K, V> map)   { super(map); }
4405	<	public final boolean contains(Object o) { return map.containsKey(o); }
4406	<	public final boolean remove(Object o)   { return map.remove(o) != null; }
4407	<	public final Iterator<K> iterator() {
4408	<	return new KeyIterator<K,V>(map);
4403	>	/**
4404	>	* A view of a ConcurrentHashMapV8 as a {@link Set} of keys, in
4405	>	* which additions may optionally be enabled by mapping to a
4406	>	* common value.  This class cannot be directly instantiated.
4407	>	* See {@link #keySet() keySet()},
4408	>	* {@link #keySet(Object) keySet(V)},
4409	>	* {@link #newKeySet() newKeySet()},
4410	>	* {@link #newKeySet(int) newKeySet(int)}.
4411	>	*
4412	>	* @since 1.8
4413	>	*/
4414	>	public static class KeySetView<K,V> extends CollectionView<K,V,K>
4415	>	implements Set<K>, java.io.Serializable {
4416	>	private static final long serialVersionUID = 7249069246763182397L;
4417	>	private final V value;
4418	>	KeySetView(ConcurrentHashMapV8<K,V> map, V value) {  // non-public
4419	>	super(map);
4420	>	this.value = value;
4421		}
4422	<	public final boolean add(K e) {
4423	<	throw new UnsupportedOperationException();
4422	>
4423	>	/**
4424	>	* Returns the default mapped value for additions,
4425	>	* or {@code null} if additions are not supported.
4426	>	*
4427	>	* @return the default mapped value for additions, or {@code null}
4428	>	* if not supported
4429	>	*/
4430	>	public V getMappedValue() { return value; }
4431	>
4432	>	/**
4433	>	* {@inheritDoc}
4434	>	* @throws NullPointerException if the specified key is null
4435	>	*/
4436	>	public boolean contains(Object o) { return map.containsKey(o); }
4437	>
4438	>	/**
4439	>	* Removes the key from this map view, by removing the key (and its
4440	>	* corresponding value) from the backing map.  This method does
4441	>	* nothing if the key is not in the map.
4442	>	*
4443	>	* @param  o the key to be removed from the backing map
4444	>	* @return {@code true} if the backing map contained the specified key
4445	>	* @throws NullPointerException if the specified key is null
4446	>	*/
4447	>	public boolean remove(Object o) { return map.remove(o) != null; }
4448	>
4449	>	/**
4450	>	* @return an iterator over the keys of the backing map
4451	>	*/
4452	>	public Iterator<K> iterator() {
4453	>	Node<K,V>[] t;
4454	>	ConcurrentHashMapV8<K,V> m = map;
4455	>	int f = (t = m.table) == null ? 0 : t.length;
4456	>	return new KeyIterator<K,V>(t, f, 0, f, m);
4457		}
4458	<	public final boolean addAll(Collection<? extends K> c) {
4459	<	throw new UnsupportedOperationException();
4458	>
4459	>	/**
4460	>	* Adds the specified key to this set view by mapping the key to
4461	>	* the default mapped value in the backing map, if defined.
4462	>	*
4463	>	* @param e key to be added
4464	>	* @return {@code true} if this set changed as a result of the call
4465	>	* @throws NullPointerException if the specified key is null
4466	>	* @throws UnsupportedOperationException if no default mapped value
4467	>	* for additions was provided
4468	>	*/
4469	>	public boolean add(K e) {
4470	>	V v;
4471	>	if ((v = value) == null)
4472	>	throw new UnsupportedOperationException();
4473	>	return map.putVal(e, v, true) == null;
4474	>	}
4475	>
4476	>	/**
4477	>	* Adds all of the elements in the specified collection to this set,
4478	>	* as if by calling {@link #add} on each one.
4479	>	*
4480	>	* @param c the elements to be inserted into this set
4481	>	* @return {@code true} if this set changed as a result of the call
4482	>	* @throws NullPointerException if the collection or any of its
4483	>	* elements are {@code null}
4484	>	* @throws UnsupportedOperationException if no default mapped value
4485	>	* for additions was provided
4486	>	*/
4487	>	public boolean addAll(Collection<? extends K> c) {
4488	>	boolean added = false;
4489	>	V v;
4490	>	if ((v = value) == null)
4491	>	throw new UnsupportedOperationException();
4492	>	for (K e : c) {
4493	>	if (map.putVal(e, v, true) == null)
4494	>	added = true;
4495	>	}
4496	>	return added;
4497		}
4498	+
4499	+	public int hashCode() {
4500	+	int h = 0;
4501	+	for (K e : this)
4502	+	h += e.hashCode();
4503	+	return h;
4504	+	}
4505	+
4506		public boolean equals(Object o) {
4507		Set<?> c;
4508		return ((o instanceof Set) &&
4509		((c = (Set<?>)o) == this ||
4510		(containsAll(c) && c.containsAll(this))));
4511		}
4512	+
4513	+	public ConcurrentHashMapSpliterator<K> spliterator() {
4514	+	Node<K,V>[] t;
4515	+	ConcurrentHashMapV8<K,V> m = map;
4516	+	long n = m.sumCount();
4517	+	int f = (t = m.table) == null ? 0 : t.length;
4518	+	return new KeySpliterator<K,V>(t, f, 0, f, n < 0L ? 0L : n);
4519	+	}
4520	+
4521	+	public void forEach(Action<? super K> action) {
4522	+	if (action == null) throw new NullPointerException();
4523	+	Node<K,V>[] t;
4524	+	if ((t = map.table) != null) {
4525	+	Traverser<K,V> it = new Traverser<K,V>(t, t.length, 0, t.length);
4526	+	for (Node<K,V> p; (p = it.advance()) != null; )
4527	+	action.apply(p.key);
4528	+	}
4529	+	}
4530		}
4531
4532	<	static final class Values<K,V> extends MapView<K,V>
4533	<	implements Collection<V> {
4534	<	Values(ConcurrentHashMapV8<K, V> map)   { super(map); }
4535	<	public final boolean contains(Object o) { return map.containsValue(o); }
4532	>	/**
4533	>	* A view of a ConcurrentHashMapV8 as a {@link Collection} of
4534	>	* values, in which additions are disabled. This class cannot be
4535	>	* directly instantiated. See {@link #values()}.
4536	>	*/
4537	>	static final class ValuesView<K,V> extends CollectionView<K,V,V>
4538	>	implements Collection<V>, java.io.Serializable {
4539	>	private static final long serialVersionUID = 2249069246763182397L;
4540	>	ValuesView(ConcurrentHashMapV8<K,V> map) { super(map); }
4541	>	public final boolean contains(Object o) {
4542	>	return map.containsValue(o);
4543	>	}
4544	>
4545		public final boolean remove(Object o) {
4546		if (o != null) {
4547	<	Iterator<V> it = new ValueIterator<K,V>(map);
3117	<	while (it.hasNext()) {
4547	>	for (Iterator<V> it = iterator(); it.hasNext();) {
4548		if (o.equals(it.next())) {
4549		it.remove();
4550		return true;
#	Line 3123 | Line 4553 | public class ConcurrentHashMapV8<K, V>
4553		}
4554		return false;
4555		}
4556	+
4557		public final Iterator<V> iterator() {
4558	<	return new ValueIterator<K,V>(map);
4558	>	ConcurrentHashMapV8<K,V> m = map;
4559	>	Node<K,V>[] t;
4560	>	int f = (t = m.table) == null ? 0 : t.length;
4561	>	return new ValueIterator<K,V>(t, f, 0, f, m);
4562		}
4563	+
4564		public final boolean add(V e) {
4565		throw new UnsupportedOperationException();
4566		}
4567		public final boolean addAll(Collection<? extends V> c) {
4568		throw new UnsupportedOperationException();
4569		}
4570	+
4571	+	public ConcurrentHashMapSpliterator<V> spliterator() {
4572	+	Node<K,V>[] t;
4573	+	ConcurrentHashMapV8<K,V> m = map;
4574	+	long n = m.sumCount();
4575	+	int f = (t = m.table) == null ? 0 : t.length;
4576	+	return new ValueSpliterator<K,V>(t, f, 0, f, n < 0L ? 0L : n);
4577	+	}
4578	+
4579	+	public void forEach(Action<? super V> action) {
4580	+	if (action == null) throw new NullPointerException();
4581	+	Node<K,V>[] t;
4582	+	if ((t = map.table) != null) {
4583	+	Traverser<K,V> it = new Traverser<K,V>(t, t.length, 0, t.length);
4584	+	for (Node<K,V> p; (p = it.advance()) != null; )
4585	+	action.apply(p.val);
4586	+	}
4587	+	}
4588		}
4589
4590	<	static final class EntrySet<K,V> extends MapView<K,V>
4591	<	implements Set<Map.Entry<K,V>> {
4592	<	EntrySet(ConcurrentHashMapV8<K, V> map) { super(map); }
4593	<	public final boolean contains(Object o) {
4590	>	/**
4591	>	* A view of a ConcurrentHashMapV8 as a {@link Set} of (key, value)
4592	>	* entries.  This class cannot be directly instantiated. See
4593	>	* {@link #entrySet()}.
4594	>	*/
4595	>	static final class EntrySetView<K,V> extends CollectionView<K,V,Map.Entry<K,V>>
4596	>	implements Set<Map.Entry<K,V>>, java.io.Serializable {
4597	>	private static final long serialVersionUID = 2249069246763182397L;
4598	>	EntrySetView(ConcurrentHashMapV8<K,V> map) { super(map); }
4599	>
4600	>	public boolean contains(Object o) {
4601		Object k, v, r; Map.Entry<?,?> e;
4602		return ((o instanceof Map.Entry) &&
4603		(k = (e = (Map.Entry<?,?>)o).getKey()) != null &&
#	Line 3145 | Line 4605 | public class ConcurrentHashMapV8<K, V>
4605		(v = e.getValue()) != null &&
4606		(v == r || v.equals(r)));
4607		}
4608	<	public final boolean remove(Object o) {
4608	>
4609	>	public boolean remove(Object o) {
4610		Object k, v; Map.Entry<?,?> e;
4611		return ((o instanceof Map.Entry) &&
4612		(k = (e = (Map.Entry<?,?>)o).getKey()) != null &&
4613		(v = e.getValue()) != null &&
4614		map.remove(k, v));
4615		}
4616	<	public final Iterator<Map.Entry<K,V>> iterator() {
4617	<	return new EntryIterator<K,V>(map);
4616	>
4617	>	/**
4618	>	* @return an iterator over the entries of the backing map
4619	>	*/
4620	>	public Iterator<Map.Entry<K,V>> iterator() {
4621	>	ConcurrentHashMapV8<K,V> m = map;
4622	>	Node<K,V>[] t;
4623	>	int f = (t = m.table) == null ? 0 : t.length;
4624	>	return new EntryIterator<K,V>(t, f, 0, f, m);
4625		}
4626	<	public final boolean add(Entry<K,V> e) {
4627	<	throw new UnsupportedOperationException();
4626	>
4627	>	public boolean add(Entry<K,V> e) {
4628	>	return map.putVal(e.getKey(), e.getValue(), false) == null;
4629		}
4630	<	public final boolean addAll(Collection<? extends Entry<K,V>> c) {
4631	<	throw new UnsupportedOperationException();
4630	>
4631	>	public boolean addAll(Collection<? extends Entry<K,V>> c) {
4632	>	boolean added = false;
4633	>	for (Entry<K,V> e : c) {
4634	>	if (add(e))
4635	>	added = true;
4636	>	}
4637	>	return added;
4638		}
4639	<	public boolean equals(Object o) {
4639	>
4640	>	public final int hashCode() {
4641	>	int h = 0;
4642	>	Node<K,V>[] t;
4643	>	if ((t = map.table) != null) {
4644	>	Traverser<K,V> it = new Traverser<K,V>(t, t.length, 0, t.length);
4645	>	for (Node<K,V> p; (p = it.advance()) != null; ) {
4646	>	h += p.hashCode();
4647	>	}
4648	>	}
4649	>	return h;
4650	>	}
4651	>
4652	>	public final boolean equals(Object o) {
4653		Set<?> c;
4654		return ((o instanceof Set) &&
4655		((c = (Set<?>)o) == this ||
4656		(containsAll(c) && c.containsAll(this))));
4657		}
4658	+
4659	+	public ConcurrentHashMapSpliterator<Map.Entry<K,V>> spliterator() {
4660	+	Node<K,V>[] t;
4661	+	ConcurrentHashMapV8<K,V> m = map;
4662	+	long n = m.sumCount();
4663	+	int f = (t = m.table) == null ? 0 : t.length;
4664	+	return new EntrySpliterator<K,V>(t, f, 0, f, n < 0L ? 0L : n, m);
4665	+	}
4666	+
4667	+	public void forEach(Action<? super Map.Entry<K,V>> action) {
4668	+	if (action == null) throw new NullPointerException();
4669	+	Node<K,V>[] t;
4670	+	if ((t = map.table) != null) {
4671	+	Traverser<K,V> it = new Traverser<K,V>(t, t.length, 0, t.length);
4672	+	for (Node<K,V> p; (p = it.advance()) != null; )
4673	+	action.apply(new MapEntry<K,V>(p.key, p.val, map));
4674	+	}
4675	+	}
4676	+
4677		}
4678
4679	<	/* ---------------- Serialization Support -------------- */
4679	>	// -------------------------------------------------------
4680
4681		/**
4682	<	* Stripped-down version of helper class used in previous version,
4683	<	* declared for the sake of serialization compatibility
4682	>	* Base class for bulk tasks. Repeats some fields and code from
4683	>	* class Traverser, because we need to subclass CountedCompleter.
4684		*/
4685	<	static class Segment<K,V> implements Serializable {
4686	<	private static final long serialVersionUID = 2249069246763182397L;
4687	<	final float loadFactor;
4688	<	Segment(float lf) { this.loadFactor = lf; }
4685	>	abstract static class BulkTask<K,V,R> extends CountedCompleter<R> {
4686	>	Node<K,V>[] tab;        // same as Traverser
4687	>	Node<K,V> next;
4688	>	int index;
4689	>	int baseIndex;
4690	>	int baseLimit;
4691	>	final int baseSize;
4692	>	int batch;              // split control
4693	>
4694	>	BulkTask(BulkTask<K,V,?> par, int b, int i, int f, Node<K,V>[] t) {
4695	>	super(par);
4696	>	this.batch = b;
4697	>	this.index = this.baseIndex = i;
4698	>	if ((this.tab = t) == null)
4699	>	this.baseSize = this.baseLimit = 0;
4700	>	else if (par == null)
4701	>	this.baseSize = this.baseLimit = t.length;
4702	>	else {
4703	>	this.baseLimit = f;
4704	>	this.baseSize = par.baseSize;
4705	>	}
4706	>	}
4707	>
4708	>	/**
4709	>	* Same as Traverser version
4710	>	*/
4711	>	final Node<K,V> advance() {
4712	>	Node<K,V> e;
4713	>	if ((e = next) != null)
4714	>	e = e.next;
4715	>	for (;;) {
4716	>	Node<K,V>[] t; int i, n; K ek;  // must use locals in checks
4717	>	if (e != null)
4718	>	return next = e;
4719	>	if (baseIndex >= baseLimit || (t = tab) == null ||
4720	>	(n = t.length) <= (i = index) || i < 0)
4721	>	return next = null;
4722	>	if ((e = tabAt(t, index)) != null && e.hash < 0) {
4723	>	if (e instanceof ForwardingNode) {
4724	>	tab = ((ForwardingNode<K,V>)e).nextTable;
4725	>	e = null;
4726	>	continue;
4727	>	}
4728	>	else if (e instanceof TreeBin)
4729	>	e = ((TreeBin<K,V>)e).first;
4730	>	else
4731	>	e = null;
4732	>	}
4733	>	if ((index += baseSize) >= n)
4734	>	index = ++baseIndex;    // visit upper slots if present
4735	>	}
4736	>	}
4737		}
4738
4739	<	/**
4740	<	* Saves the state of the {@code ConcurrentHashMapV8} instance to a
4741	<	* stream (i.e., serializes it).
4742	<	* @param s the stream
4743	<	* @serialData
4744	<	* the key (Object) and value (Object)
4745	<	* for each key-value mapping, followed by a null pair.
4746	<	* The key-value mappings are emitted in no particular order.
4747	<	*/
4748	<	@SuppressWarnings("unchecked")
4749	<	private void writeObject(java.io.ObjectOutputStream s)
4750	<	throws java.io.IOException {
4751	<	if (segments == null) { // for serialization compatibility
4752	<	segments = (Segment<K,V>[])
4753	<	new Segment<?,?>[DEFAULT_CONCURRENCY_LEVEL];
4754	<	for (int i = 0; i < segments.length; ++i)
4755	<	segments[i] = new Segment<K,V>(LOAD_FACTOR);
4756	<	}
4757	<	s.defaultWriteObject();
4758	<	InternalIterator<K,V> it = new InternalIterator<K,V>(this);
4759	<	Object v;
4760	<	while ((v = it.advance()) != null) {
4761	<	s.writeObject(it.nextKey);
4762	<	s.writeObject(v);
4739	>	/*
4740	>	* Task classes. Coded in a regular but ugly format/style to
4741	>	* simplify checks that each variant differs in the right way from
4742	>	* others. The null screenings exist because compilers cannot tell
4743	>	* that we've already null-checked task arguments, so we force
4744	>	* simplest hoisted bypass to help avoid convoluted traps.
4745	>	*/
4746	>	@SuppressWarnings("serial")
4747	>	static final class ForEachKeyTask<K,V>
4748	>	extends BulkTask<K,V,Void> {
4749	>	final Action<? super K> action;
4750	>	ForEachKeyTask
4751	>	(BulkTask<K,V,?> p, int b, int i, int f, Node<K,V>[] t,
4752	>	Action<? super K> action) {
4753	>	super(p, b, i, f, t);
4754	>	this.action = action;
4755	>	}
4756	>	public final void compute() {
4757	>	final Action<? super K> action;
4758	>	if ((action = this.action) != null) {
4759	>	for (int i = baseIndex, f, h; batch > 0 &&
4760	>	(h = ((f = baseLimit) + i) >>> 1) > i;) {
4761	>	addToPendingCount(1);
4762	>	new ForEachKeyTask<K,V>
4763	>	(this, batch >>>= 1, baseLimit = h, f, tab,
4764	>	action).fork();
4765	>	}
4766	>	for (Node<K,V> p; (p = advance()) != null;)
4767	>	action.apply(p.key);
4768	>	propagateCompletion();
4769	>	}
4770	>	}
4771	>	}
4772	>
4773	>	@SuppressWarnings("serial")
4774	>	static final class ForEachValueTask<K,V>
4775	>	extends BulkTask<K,V,Void> {
4776	>	final Action<? super V> action;
4777	>	ForEachValueTask
4778	>	(BulkTask<K,V,?> p, int b, int i, int f, Node<K,V>[] t,
4779	>	Action<? super V> action) {
4780	>	super(p, b, i, f, t);
4781	>	this.action = action;
4782	>	}
4783	>	public final void compute() {
4784	>	final Action<? super V> action;
4785	>	if ((action = this.action) != null) {
4786	>	for (int i = baseIndex, f, h; batch > 0 &&
4787	>	(h = ((f = baseLimit) + i) >>> 1) > i;) {
4788	>	addToPendingCount(1);
4789	>	new ForEachValueTask<K,V>
4790	>	(this, batch >>>= 1, baseLimit = h, f, tab,
4791	>	action).fork();
4792	>	}
4793	>	for (Node<K,V> p; (p = advance()) != null;)
4794	>	action.apply(p.val);
4795	>	propagateCompletion();
4796	>	}
4797	>	}
4798	>	}
4799	>
4800	>	@SuppressWarnings("serial")
4801	>	static final class ForEachEntryTask<K,V>
4802	>	extends BulkTask<K,V,Void> {
4803	>	final Action<? super Entry<K,V>> action;
4804	>	ForEachEntryTask
4805	>	(BulkTask<K,V,?> p, int b, int i, int f, Node<K,V>[] t,
4806	>	Action<? super Entry<K,V>> action) {
4807	>	super(p, b, i, f, t);
4808	>	this.action = action;
4809	>	}
4810	>	public final void compute() {
4811	>	final Action<? super Entry<K,V>> action;
4812	>	if ((action = this.action) != null) {
4813	>	for (int i = baseIndex, f, h; batch > 0 &&
4814	>	(h = ((f = baseLimit) + i) >>> 1) > i;) {
4815	>	addToPendingCount(1);
4816	>	new ForEachEntryTask<K,V>
4817	>	(this, batch >>>= 1, baseLimit = h, f, tab,
4818	>	action).fork();
4819	>	}
4820	>	for (Node<K,V> p; (p = advance()) != null; )
4821	>	action.apply(p);
4822	>	propagateCompletion();
4823	>	}
4824	>	}
4825	>	}
4826	>
4827	>	@SuppressWarnings("serial")
4828	>	static final class ForEachMappingTask<K,V>
4829	>	extends BulkTask<K,V,Void> {
4830	>	final BiAction<? super K, ? super V> action;
4831	>	ForEachMappingTask
4832	>	(BulkTask<K,V,?> p, int b, int i, int f, Node<K,V>[] t,
4833	>	BiAction<? super K,? super V> action) {
4834	>	super(p, b, i, f, t);
4835	>	this.action = action;
4836	>	}
4837	>	public final void compute() {
4838	>	final BiAction<? super K, ? super V> action;
4839	>	if ((action = this.action) != null) {
4840	>	for (int i = baseIndex, f, h; batch > 0 &&
4841	>	(h = ((f = baseLimit) + i) >>> 1) > i;) {
4842	>	addToPendingCount(1);
4843	>	new ForEachMappingTask<K,V>
4844	>	(this, batch >>>= 1, baseLimit = h, f, tab,
4845	>	action).fork();
4846	>	}
4847	>	for (Node<K,V> p; (p = advance()) != null; )
4848	>	action.apply(p.key, p.val);
4849	>	propagateCompletion();
4850	>	}
4851	>	}
4852	>	}
4853	>
4854	>	@SuppressWarnings("serial")
4855	>	static final class ForEachTransformedKeyTask<K,V,U>
4856	>	extends BulkTask<K,V,Void> {
4857	>	final Fun<? super K, ? extends U> transformer;
4858	>	final Action<? super U> action;
4859	>	ForEachTransformedKeyTask
4860	>	(BulkTask<K,V,?> p, int b, int i, int f, Node<K,V>[] t,
4861	>	Fun<? super K, ? extends U> transformer, Action<? super U> action) {
4862	>	super(p, b, i, f, t);
4863	>	this.transformer = transformer; this.action = action;
4864	>	}
4865	>	public final void compute() {
4866	>	final Fun<? super K, ? extends U> transformer;
4867	>	final Action<? super U> action;
4868	>	if ((transformer = this.transformer) != null &&
4869	>	(action = this.action) != null) {
4870	>	for (int i = baseIndex, f, h; batch > 0 &&
4871	>	(h = ((f = baseLimit) + i) >>> 1) > i;) {
4872	>	addToPendingCount(1);
4873	>	new ForEachTransformedKeyTask<K,V,U>
4874	>	(this, batch >>>= 1, baseLimit = h, f, tab,
4875	>	transformer, action).fork();
4876	>	}
4877	>	for (Node<K,V> p; (p = advance()) != null; ) {
4878	>	U u;
4879	>	if ((u = transformer.apply(p.key)) != null)
4880	>	action.apply(u);
4881	>	}
4882	>	propagateCompletion();
4883	>	}
4884	>	}
4885	>	}
4886	>
4887	>	@SuppressWarnings("serial")
4888	>	static final class ForEachTransformedValueTask<K,V,U>
4889	>	extends BulkTask<K,V,Void> {
4890	>	final Fun<? super V, ? extends U> transformer;
4891	>	final Action<? super U> action;
4892	>	ForEachTransformedValueTask
4893	>	(BulkTask<K,V,?> p, int b, int i, int f, Node<K,V>[] t,
4894	>	Fun<? super V, ? extends U> transformer, Action<? super U> action) {
4895	>	super(p, b, i, f, t);
4896	>	this.transformer = transformer; this.action = action;
4897	>	}
4898	>	public final void compute() {
4899	>	final Fun<? super V, ? extends U> transformer;
4900	>	final Action<? super U> action;
4901	>	if ((transformer = this.transformer) != null &&
4902	>	(action = this.action) != null) {
4903	>	for (int i = baseIndex, f, h; batch > 0 &&
4904	>	(h = ((f = baseLimit) + i) >>> 1) > i;) {
4905	>	addToPendingCount(1);
4906	>	new ForEachTransformedValueTask<K,V,U>
4907	>	(this, batch >>>= 1, baseLimit = h, f, tab,
4908	>	transformer, action).fork();
4909	>	}
4910	>	for (Node<K,V> p; (p = advance()) != null; ) {
4911	>	U u;
4912	>	if ((u = transformer.apply(p.val)) != null)
4913	>	action.apply(u);
4914	>	}
4915	>	propagateCompletion();
4916	>	}
4917	>	}
4918	>	}
4919	>
4920	>	@SuppressWarnings("serial")
4921	>	static final class ForEachTransformedEntryTask<K,V,U>
4922	>	extends BulkTask<K,V,Void> {
4923	>	final Fun<Map.Entry<K,V>, ? extends U> transformer;
4924	>	final Action<? super U> action;
4925	>	ForEachTransformedEntryTask
4926	>	(BulkTask<K,V,?> p, int b, int i, int f, Node<K,V>[] t,
4927	>	Fun<Map.Entry<K,V>, ? extends U> transformer, Action<? super U> action) {
4928	>	super(p, b, i, f, t);
4929	>	this.transformer = transformer; this.action = action;
4930	>	}
4931	>	public final void compute() {
4932	>	final Fun<Map.Entry<K,V>, ? extends U> transformer;
4933	>	final Action<? super U> action;
4934	>	if ((transformer = this.transformer) != null &&
4935	>	(action = this.action) != null) {
4936	>	for (int i = baseIndex, f, h; batch > 0 &&
4937	>	(h = ((f = baseLimit) + i) >>> 1) > i;) {
4938	>	addToPendingCount(1);
4939	>	new ForEachTransformedEntryTask<K,V,U>
4940	>	(this, batch >>>= 1, baseLimit = h, f, tab,
4941	>	transformer, action).fork();
4942	>	}
4943	>	for (Node<K,V> p; (p = advance()) != null; ) {
4944	>	U u;
4945	>	if ((u = transformer.apply(p)) != null)
4946	>	action.apply(u);
4947	>	}
4948	>	propagateCompletion();
4949	>	}
4950	>	}
4951	>	}
4952	>
4953	>	@SuppressWarnings("serial")
4954	>	static final class ForEachTransformedMappingTask<K,V,U>
4955	>	extends BulkTask<K,V,Void> {
4956	>	final BiFun<? super K, ? super V, ? extends U> transformer;
4957	>	final Action<? super U> action;
4958	>	ForEachTransformedMappingTask
4959	>	(BulkTask<K,V,?> p, int b, int i, int f, Node<K,V>[] t,
4960	>	BiFun<? super K, ? super V, ? extends U> transformer,
4961	>	Action<? super U> action) {
4962	>	super(p, b, i, f, t);
4963	>	this.transformer = transformer; this.action = action;
4964	>	}
4965	>	public final void compute() {
4966	>	final BiFun<? super K, ? super V, ? extends U> transformer;
4967	>	final Action<? super U> action;
4968	>	if ((transformer = this.transformer) != null &&
4969	>	(action = this.action) != null) {
4970	>	for (int i = baseIndex, f, h; batch > 0 &&
4971	>	(h = ((f = baseLimit) + i) >>> 1) > i;) {
4972	>	addToPendingCount(1);
4973	>	new ForEachTransformedMappingTask<K,V,U>
4974	>	(this, batch >>>= 1, baseLimit = h, f, tab,
4975	>	transformer, action).fork();
4976	>	}
4977	>	for (Node<K,V> p; (p = advance()) != null; ) {
4978	>	U u;
4979	>	if ((u = transformer.apply(p.key, p.val)) != null)
4980	>	action.apply(u);
4981	>	}
4982	>	propagateCompletion();
4983	>	}
4984	>	}
4985	>	}
4986	>
4987	>	@SuppressWarnings("serial")
4988	>	static final class SearchKeysTask<K,V,U>
4989	>	extends BulkTask<K,V,U> {
4990	>	final Fun<? super K, ? extends U> searchFunction;
4991	>	final AtomicReference<U> result;
4992	>	SearchKeysTask
4993	>	(BulkTask<K,V,?> p, int b, int i, int f, Node<K,V>[] t,
4994	>	Fun<? super K, ? extends U> searchFunction,
4995	>	AtomicReference<U> result) {
4996	>	super(p, b, i, f, t);
4997	>	this.searchFunction = searchFunction; this.result = result;
4998	>	}
4999	>	public final U getRawResult() { return result.get(); }
5000	>	public final void compute() {
5001	>	final Fun<? super K, ? extends U> searchFunction;
5002	>	final AtomicReference<U> result;
5003	>	if ((searchFunction = this.searchFunction) != null &&
5004	>	(result = this.result) != null) {
5005	>	for (int i = baseIndex, f, h; batch > 0 &&
5006	>	(h = ((f = baseLimit) + i) >>> 1) > i;) {
5007	>	if (result.get() != null)
5008	>	return;
5009	>	addToPendingCount(1);
5010	>	new SearchKeysTask<K,V,U>
5011	>	(this, batch >>>= 1, baseLimit = h, f, tab,
5012	>	searchFunction, result).fork();
5013	>	}
5014	>	while (result.get() == null) {
5015	>	U u;
5016	>	Node<K,V> p;
5017	>	if ((p = advance()) == null) {
5018	>	propagateCompletion();
5019	>	break;
5020	>	}
5021	>	if ((u = searchFunction.apply(p.key)) != null) {
5022	>	if (result.compareAndSet(null, u))
5023	>	quietlyCompleteRoot();
5024	>	break;
5025	>	}
5026	>	}
5027	>	}
5028		}
3209	–	s.writeObject(null);
3210	–	s.writeObject(null);
3211	–	segments = null; // throw away
5029		}
5030
5031	<	/**
5032	<	* Reconstitutes the instance from a stream (that is, deserializes it).
5033	<	* @param s the stream
5034	<	*/
5035	<	@SuppressWarnings("unchecked")
5036	<	private void readObject(java.io.ObjectInputStream s)
5037	<	throws java.io.IOException, ClassNotFoundException {
5038	<	s.defaultReadObject();
5039	<	this.segments = null; // unneeded
5040	<	// initialize transient final field
5041	<	UNSAFE.putObjectVolatile(this, counterOffset, new LongAdder());
5031	>	@SuppressWarnings("serial")
5032	>	static final class SearchValuesTask<K,V,U>
5033	>	extends BulkTask<K,V,U> {
5034	>	final Fun<? super V, ? extends U> searchFunction;
5035	>	final AtomicReference<U> result;
5036	>	SearchValuesTask
5037	>	(BulkTask<K,V,?> p, int b, int i, int f, Node<K,V>[] t,
5038	>	Fun<? super V, ? extends U> searchFunction,
5039	>	AtomicReference<U> result) {
5040	>	super(p, b, i, f, t);
5041	>	this.searchFunction = searchFunction; this.result = result;
5042	>	}
5043	>	public final U getRawResult() { return result.get(); }
5044	>	public final void compute() {
5045	>	final Fun<? super V, ? extends U> searchFunction;
5046	>	final AtomicReference<U> result;
5047	>	if ((searchFunction = this.searchFunction) != null &&
5048	>	(result = this.result) != null) {
5049	>	for (int i = baseIndex, f, h; batch > 0 &&
5050	>	(h = ((f = baseLimit) + i) >>> 1) > i;) {
5051	>	if (result.get() != null)
5052	>	return;
5053	>	addToPendingCount(1);
5054	>	new SearchValuesTask<K,V,U>
5055	>	(this, batch >>>= 1, baseLimit = h, f, tab,
5056	>	searchFunction, result).fork();
5057	>	}
5058	>	while (result.get() == null) {
5059	>	U u;
5060	>	Node<K,V> p;
5061	>	if ((p = advance()) == null) {
5062	>	propagateCompletion();
5063	>	break;
5064	>	}
5065	>	if ((u = searchFunction.apply(p.val)) != null) {
5066	>	if (result.compareAndSet(null, u))
5067	>	quietlyCompleteRoot();
5068	>	break;
5069	>	}
5070	>	}
5071	>	}
5072	>	}
5073	>	}
5074
5075	<	// Create all nodes, then place in table once size is known
5076	<	long size = 0L;
5077	<	Node p = null;
5078	<	for (;;) {
5079	<	K k = (K) s.readObject();
5080	<	V v = (V) s.readObject();
5081	<	if (k != null && v != null) {
5082	<	int h = spread(k.hashCode());
5083	<	p = new Node(h, k, v, p);
5084	<	++size;
5075	>	@SuppressWarnings("serial")
5076	>	static final class SearchEntriesTask<K,V,U>
5077	>	extends BulkTask<K,V,U> {
5078	>	final Fun<Entry<K,V>, ? extends U> searchFunction;
5079	>	final AtomicReference<U> result;
5080	>	SearchEntriesTask
5081	>	(BulkTask<K,V,?> p, int b, int i, int f, Node<K,V>[] t,
5082	>	Fun<Entry<K,V>, ? extends U> searchFunction,
5083	>	AtomicReference<U> result) {
5084	>	super(p, b, i, f, t);
5085	>	this.searchFunction = searchFunction; this.result = result;
5086	>	}
5087	>	public final U getRawResult() { return result.get(); }
5088	>	public final void compute() {
5089	>	final Fun<Entry<K,V>, ? extends U> searchFunction;
5090	>	final AtomicReference<U> result;
5091	>	if ((searchFunction = this.searchFunction) != null &&
5092	>	(result = this.result) != null) {
5093	>	for (int i = baseIndex, f, h; batch > 0 &&
5094	>	(h = ((f = baseLimit) + i) >>> 1) > i;) {
5095	>	if (result.get() != null)
5096	>	return;
5097	>	addToPendingCount(1);
5098	>	new SearchEntriesTask<K,V,U>
5099	>	(this, batch >>>= 1, baseLimit = h, f, tab,
5100	>	searchFunction, result).fork();
5101	>	}
5102	>	while (result.get() == null) {
5103	>	U u;
5104	>	Node<K,V> p;
5105	>	if ((p = advance()) == null) {
5106	>	propagateCompletion();
5107	>	break;
5108	>	}
5109	>	if ((u = searchFunction.apply(p)) != null) {
5110	>	if (result.compareAndSet(null, u))
5111	>	quietlyCompleteRoot();
5112	>	return;
5113	>	}
5114	>	}
5115		}
3237	–	else
3238	–	break;
5116		}
5117	<	if (p != null) {
5118	<	boolean init = false;
5119	<	int n;
5120	<	if (size >= (long)(MAXIMUM_CAPACITY >>> 1))
5121	<	n = MAXIMUM_CAPACITY;
5122	<	else {
5123	<	int sz = (int)size;
5124	<	n = tableSizeFor(sz + (sz >>> 1) + 1);
5117	>	}
5118	>
5119	>	@SuppressWarnings("serial")
5120	>	static final class SearchMappingsTask<K,V,U>
5121	>	extends BulkTask<K,V,U> {
5122	>	final BiFun<? super K, ? super V, ? extends U> searchFunction;
5123	>	final AtomicReference<U> result;
5124	>	SearchMappingsTask
5125	>	(BulkTask<K,V,?> p, int b, int i, int f, Node<K,V>[] t,
5126	>	BiFun<? super K, ? super V, ? extends U> searchFunction,
5127	>	AtomicReference<U> result) {
5128	>	super(p, b, i, f, t);
5129	>	this.searchFunction = searchFunction; this.result = result;
5130	>	}
5131	>	public final U getRawResult() { return result.get(); }
5132	>	public final void compute() {
5133	>	final BiFun<? super K, ? super V, ? extends U> searchFunction;
5134	>	final AtomicReference<U> result;
5135	>	if ((searchFunction = this.searchFunction) != null &&
5136	>	(result = this.result) != null) {
5137	>	for (int i = baseIndex, f, h; batch > 0 &&
5138	>	(h = ((f = baseLimit) + i) >>> 1) > i;) {
5139	>	if (result.get() != null)
5140	>	return;
5141	>	addToPendingCount(1);
5142	>	new SearchMappingsTask<K,V,U>
5143	>	(this, batch >>>= 1, baseLimit = h, f, tab,
5144	>	searchFunction, result).fork();
5145	>	}
5146	>	while (result.get() == null) {
5147	>	U u;
5148	>	Node<K,V> p;
5149	>	if ((p = advance()) == null) {
5150	>	propagateCompletion();
5151	>	break;
5152	>	}
5153	>	if ((u = searchFunction.apply(p.key, p.val)) != null) {
5154	>	if (result.compareAndSet(null, u))
5155	>	quietlyCompleteRoot();
5156	>	break;
5157	>	}
5158	>	}
5159		}
5160	<	int sc = sizeCtl;
5161	<	boolean collide = false;
5162	<	if (n > sc &&
5163	<	UNSAFE.compareAndSwapInt(this, sizeCtlOffset, sc, -1)) {
5164	<	try {
5165	<	if (table == null) {
5166	<	init = true;
5167	<	Node[] tab = new Node[n];
5168	<	int mask = n - 1;
5169	<	while (p != null) {
5170	<	int j = p.hash & mask;
5171	<	Node next = p.next;
5172	<	Node q = p.next = tabAt(tab, j);
5173	<	setTabAt(tab, j, p);
5174	<	if (!collide && q != null && q.hash == p.hash)
5175	<	collide = true;
5176	<	p = next;
5160	>	}
5161	>	}
5162	>
5163	>	@SuppressWarnings("serial")
5164	>	static final class ReduceKeysTask<K,V>
5165	>	extends BulkTask<K,V,K> {
5166	>	final BiFun<? super K, ? super K, ? extends K> reducer;
5167	>	K result;
5168	>	ReduceKeysTask<K,V> rights, nextRight;
5169	>	ReduceKeysTask
5170	>	(BulkTask<K,V,?> p, int b, int i, int f, Node<K,V>[] t,
5171	>	ReduceKeysTask<K,V> nextRight,
5172	>	BiFun<? super K, ? super K, ? extends K> reducer) {
5173	>	super(p, b, i, f, t); this.nextRight = nextRight;
5174	>	this.reducer = reducer;
5175	>	}
5176	>	public final K getRawResult() { return result; }
5177	>	public final void compute() {
5178	>	final BiFun<? super K, ? super K, ? extends K> reducer;
5179	>	if ((reducer = this.reducer) != null) {
5180	>	for (int i = baseIndex, f, h; batch > 0 &&
5181	>	(h = ((f = baseLimit) + i) >>> 1) > i;) {
5182	>	addToPendingCount(1);
5183	>	(rights = new ReduceKeysTask<K,V>
5184	>	(this, batch >>>= 1, baseLimit = h, f, tab,
5185	>	rights, reducer)).fork();
5186	>	}
5187	>	K r = null;
5188	>	for (Node<K,V> p; (p = advance()) != null; ) {
5189	>	K u = p.key;
5190	>	r = (r == null) ? u : u == null ? r : reducer.apply(r, u);
5191	>	}
5192	>	result = r;
5193	>	CountedCompleter<?> c;
5194	>	for (c = firstComplete(); c != null; c = c.nextComplete()) {
5195	>	@SuppressWarnings("unchecked") ReduceKeysTask<K,V>
5196	>	t = (ReduceKeysTask<K,V>)c,
5197	>	s = t.rights;
5198	>	while (s != null) {
5199	>	K tr, sr;
5200	>	if ((sr = s.result) != null)
5201	>	t.result = (((tr = t.result) == null) ? sr :
5202	>	reducer.apply(tr, sr));
5203	>	s = t.rights = s.nextRight;
5204	>	}
5205	>	}
5206	>	}
5207	>	}
5208	>	}
5209	>
5210	>	@SuppressWarnings("serial")
5211	>	static final class ReduceValuesTask<K,V>
5212	>	extends BulkTask<K,V,V> {
5213	>	final BiFun<? super V, ? super V, ? extends V> reducer;
5214	>	V result;
5215	>	ReduceValuesTask<K,V> rights, nextRight;
5216	>	ReduceValuesTask
5217	>	(BulkTask<K,V,?> p, int b, int i, int f, Node<K,V>[] t,
5218	>	ReduceValuesTask<K,V> nextRight,
5219	>	BiFun<? super V, ? super V, ? extends V> reducer) {
5220	>	super(p, b, i, f, t); this.nextRight = nextRight;
5221	>	this.reducer = reducer;
5222	>	}
5223	>	public final V getRawResult() { return result; }
5224	>	public final void compute() {
5225	>	final BiFun<? super V, ? super V, ? extends V> reducer;
5226	>	if ((reducer = this.reducer) != null) {
5227	>	for (int i = baseIndex, f, h; batch > 0 &&
5228	>	(h = ((f = baseLimit) + i) >>> 1) > i;) {
5229	>	addToPendingCount(1);
5230	>	(rights = new ReduceValuesTask<K,V>
5231	>	(this, batch >>>= 1, baseLimit = h, f, tab,
5232	>	rights, reducer)).fork();
5233	>	}
5234	>	V r = null;
5235	>	for (Node<K,V> p; (p = advance()) != null; ) {
5236	>	V v = p.val;
5237	>	r = (r == null) ? v : reducer.apply(r, v);
5238	>	}
5239	>	result = r;
5240	>	CountedCompleter<?> c;
5241	>	for (c = firstComplete(); c != null; c = c.nextComplete()) {
5242	>	@SuppressWarnings("unchecked") ReduceValuesTask<K,V>
5243	>	t = (ReduceValuesTask<K,V>)c,
5244	>	s = t.rights;
5245	>	while (s != null) {
5246	>	V tr, sr;
5247	>	if ((sr = s.result) != null)
5248	>	t.result = (((tr = t.result) == null) ? sr :
5249	>	reducer.apply(tr, sr));
5250	>	s = t.rights = s.nextRight;
5251	>	}
5252	>	}
5253	>	}
5254	>	}
5255	>	}
5256	>
5257	>	@SuppressWarnings("serial")
5258	>	static final class ReduceEntriesTask<K,V>
5259	>	extends BulkTask<K,V,Map.Entry<K,V>> {
5260	>	final BiFun<Map.Entry<K,V>, Map.Entry<K,V>, ? extends Map.Entry<K,V>> reducer;
5261	>	Map.Entry<K,V> result;
5262	>	ReduceEntriesTask<K,V> rights, nextRight;
5263	>	ReduceEntriesTask
5264	>	(BulkTask<K,V,?> p, int b, int i, int f, Node<K,V>[] t,
5265	>	ReduceEntriesTask<K,V> nextRight,
5266	>	BiFun<Entry<K,V>, Map.Entry<K,V>, ? extends Map.Entry<K,V>> reducer) {
5267	>	super(p, b, i, f, t); this.nextRight = nextRight;
5268	>	this.reducer = reducer;
5269	>	}
5270	>	public final Map.Entry<K,V> getRawResult() { return result; }
5271	>	public final void compute() {
5272	>	final BiFun<Map.Entry<K,V>, Map.Entry<K,V>, ? extends Map.Entry<K,V>> reducer;
5273	>	if ((reducer = this.reducer) != null) {
5274	>	for (int i = baseIndex, f, h; batch > 0 &&
5275	>	(h = ((f = baseLimit) + i) >>> 1) > i;) {
5276	>	addToPendingCount(1);
5277	>	(rights = new ReduceEntriesTask<K,V>
5278	>	(this, batch >>>= 1, baseLimit = h, f, tab,
5279	>	rights, reducer)).fork();
5280	>	}
5281	>	Map.Entry<K,V> r = null;
5282	>	for (Node<K,V> p; (p = advance()) != null; )
5283	>	r = (r == null) ? p : reducer.apply(r, p);
5284	>	result = r;
5285	>	CountedCompleter<?> c;
5286	>	for (c = firstComplete(); c != null; c = c.nextComplete()) {
5287	>	@SuppressWarnings("unchecked") ReduceEntriesTask<K,V>
5288	>	t = (ReduceEntriesTask<K,V>)c,
5289	>	s = t.rights;
5290	>	while (s != null) {
5291	>	Map.Entry<K,V> tr, sr;
5292	>	if ((sr = s.result) != null)
5293	>	t.result = (((tr = t.result) == null) ? sr :
5294	>	reducer.apply(tr, sr));
5295	>	s = t.rights = s.nextRight;
5296	>	}
5297	>	}
5298	>	}
5299	>	}
5300	>	}
5301	>
5302	>	@SuppressWarnings("serial")
5303	>	static final class MapReduceKeysTask<K,V,U>
5304	>	extends BulkTask<K,V,U> {
5305	>	final Fun<? super K, ? extends U> transformer;
5306	>	final BiFun<? super U, ? super U, ? extends U> reducer;
5307	>	U result;
5308	>	MapReduceKeysTask<K,V,U> rights, nextRight;
5309	>	MapReduceKeysTask
5310	>	(BulkTask<K,V,?> p, int b, int i, int f, Node<K,V>[] t,
5311	>	MapReduceKeysTask<K,V,U> nextRight,
5312	>	Fun<? super K, ? extends U> transformer,
5313	>	BiFun<? super U, ? super U, ? extends U> reducer) {
5314	>	super(p, b, i, f, t); this.nextRight = nextRight;
5315	>	this.transformer = transformer;
5316	>	this.reducer = reducer;
5317	>	}
5318	>	public final U getRawResult() { return result; }
5319	>	public final void compute() {
5320	>	final Fun<? super K, ? extends U> transformer;
5321	>	final BiFun<? super U, ? super U, ? extends U> reducer;
5322	>	if ((transformer = this.transformer) != null &&
5323	>	(reducer = this.reducer) != null) {
5324	>	for (int i = baseIndex, f, h; batch > 0 &&
5325	>	(h = ((f = baseLimit) + i) >>> 1) > i;) {
5326	>	addToPendingCount(1);
5327	>	(rights = new MapReduceKeysTask<K,V,U>
5328	>	(this, batch >>>= 1, baseLimit = h, f, tab,
5329	>	rights, transformer, reducer)).fork();
5330	>	}
5331	>	U r = null;
5332	>	for (Node<K,V> p; (p = advance()) != null; ) {
5333	>	U u;
5334	>	if ((u = transformer.apply(p.key)) != null)
5335	>	r = (r == null) ? u : reducer.apply(r, u);
5336	>	}
5337	>	result = r;
5338	>	CountedCompleter<?> c;
5339	>	for (c = firstComplete(); c != null; c = c.nextComplete()) {
5340	>	@SuppressWarnings("unchecked") MapReduceKeysTask<K,V,U>
5341	>	t = (MapReduceKeysTask<K,V,U>)c,
5342	>	s = t.rights;
5343	>	while (s != null) {
5344	>	U tr, sr;
5345	>	if ((sr = s.result) != null)
5346	>	t.result = (((tr = t.result) == null) ? sr :
5347	>	reducer.apply(tr, sr));
5348	>	s = t.rights = s.nextRight;
5349	>	}
5350	>	}
5351	>	}
5352	>	}
5353	>	}
5354	>
5355	>	@SuppressWarnings("serial")
5356	>	static final class MapReduceValuesTask<K,V,U>
5357	>	extends BulkTask<K,V,U> {
5358	>	final Fun<? super V, ? extends U> transformer;
5359	>	final BiFun<? super U, ? super U, ? extends U> reducer;
5360	>	U result;
5361	>	MapReduceValuesTask<K,V,U> rights, nextRight;
5362	>	MapReduceValuesTask
5363	>	(BulkTask<K,V,?> p, int b, int i, int f, Node<K,V>[] t,
5364	>	MapReduceValuesTask<K,V,U> nextRight,
5365	>	Fun<? super V, ? extends U> transformer,
5366	>	BiFun<? super U, ? super U, ? extends U> reducer) {
5367	>	super(p, b, i, f, t); this.nextRight = nextRight;
5368	>	this.transformer = transformer;
5369	>	this.reducer = reducer;
5370	>	}
5371	>	public final U getRawResult() { return result; }
5372	>	public final void compute() {
5373	>	final Fun<? super V, ? extends U> transformer;
5374	>	final BiFun<? super U, ? super U, ? extends U> reducer;
5375	>	if ((transformer = this.transformer) != null &&
5376	>	(reducer = this.reducer) != null) {
5377	>	for (int i = baseIndex, f, h; batch > 0 &&
5378	>	(h = ((f = baseLimit) + i) >>> 1) > i;) {
5379	>	addToPendingCount(1);
5380	>	(rights = new MapReduceValuesTask<K,V,U>
5381	>	(this, batch >>>= 1, baseLimit = h, f, tab,
5382	>	rights, transformer, reducer)).fork();
5383	>	}
5384	>	U r = null;
5385	>	for (Node<K,V> p; (p = advance()) != null; ) {
5386	>	U u;
5387	>	if ((u = transformer.apply(p.val)) != null)
5388	>	r = (r == null) ? u : reducer.apply(r, u);
5389	>	}
5390	>	result = r;
5391	>	CountedCompleter<?> c;
5392	>	for (c = firstComplete(); c != null; c = c.nextComplete()) {
5393	>	@SuppressWarnings("unchecked") MapReduceValuesTask<K,V,U>
5394	>	t = (MapReduceValuesTask<K,V,U>)c,
5395	>	s = t.rights;
5396	>	while (s != null) {
5397	>	U tr, sr;
5398	>	if ((sr = s.result) != null)
5399	>	t.result = (((tr = t.result) == null) ? sr :
5400	>	reducer.apply(tr, sr));
5401	>	s = t.rights = s.nextRight;
5402	>	}
5403	>	}
5404	>	}
5405	>	}
5406	>	}
5407	>
5408	>	@SuppressWarnings("serial")
5409	>	static final class MapReduceEntriesTask<K,V,U>
5410	>	extends BulkTask<K,V,U> {
5411	>	final Fun<Map.Entry<K,V>, ? extends U> transformer;
5412	>	final BiFun<? super U, ? super U, ? extends U> reducer;
5413	>	U result;
5414	>	MapReduceEntriesTask<K,V,U> rights, nextRight;
5415	>	MapReduceEntriesTask
5416	>	(BulkTask<K,V,?> p, int b, int i, int f, Node<K,V>[] t,
5417	>	MapReduceEntriesTask<K,V,U> nextRight,
5418	>	Fun<Map.Entry<K,V>, ? extends U> transformer,
5419	>	BiFun<? super U, ? super U, ? extends U> reducer) {
5420	>	super(p, b, i, f, t); this.nextRight = nextRight;
5421	>	this.transformer = transformer;
5422	>	this.reducer = reducer;
5423	>	}
5424	>	public final U getRawResult() { return result; }
5425	>	public final void compute() {
5426	>	final Fun<Map.Entry<K,V>, ? extends U> transformer;
5427	>	final BiFun<? super U, ? super U, ? extends U> reducer;
5428	>	if ((transformer = this.transformer) != null &&
5429	>	(reducer = this.reducer) != null) {
5430	>	for (int i = baseIndex, f, h; batch > 0 &&
5431	>	(h = ((f = baseLimit) + i) >>> 1) > i;) {
5432	>	addToPendingCount(1);
5433	>	(rights = new MapReduceEntriesTask<K,V,U>
5434	>	(this, batch >>>= 1, baseLimit = h, f, tab,
5435	>	rights, transformer, reducer)).fork();
5436	>	}
5437	>	U r = null;
5438	>	for (Node<K,V> p; (p = advance()) != null; ) {
5439	>	U u;
5440	>	if ((u = transformer.apply(p)) != null)
5441	>	r = (r == null) ? u : reducer.apply(r, u);
5442	>	}
5443	>	result = r;
5444	>	CountedCompleter<?> c;
5445	>	for (c = firstComplete(); c != null; c = c.nextComplete()) {
5446	>	@SuppressWarnings("unchecked") MapReduceEntriesTask<K,V,U>
5447	>	t = (MapReduceEntriesTask<K,V,U>)c,
5448	>	s = t.rights;
5449	>	while (s != null) {
5450	>	U tr, sr;
5451	>	if ((sr = s.result) != null)
5452	>	t.result = (((tr = t.result) == null) ? sr :
5453	>	reducer.apply(tr, sr));
5454	>	s = t.rights = s.nextRight;
5455	>	}
5456	>	}
5457	>	}
5458	>	}
5459	>	}
5460	>
5461	>	@SuppressWarnings("serial")
5462	>	static final class MapReduceMappingsTask<K,V,U>
5463	>	extends BulkTask<K,V,U> {
5464	>	final BiFun<? super K, ? super V, ? extends U> transformer;
5465	>	final BiFun<? super U, ? super U, ? extends U> reducer;
5466	>	U result;
5467	>	MapReduceMappingsTask<K,V,U> rights, nextRight;
5468	>	MapReduceMappingsTask
5469	>	(BulkTask<K,V,?> p, int b, int i, int f, Node<K,V>[] t,
5470	>	MapReduceMappingsTask<K,V,U> nextRight,
5471	>	BiFun<? super K, ? super V, ? extends U> transformer,
5472	>	BiFun<? super U, ? super U, ? extends U> reducer) {
5473	>	super(p, b, i, f, t); this.nextRight = nextRight;
5474	>	this.transformer = transformer;
5475	>	this.reducer = reducer;
5476	>	}
5477	>	public final U getRawResult() { return result; }
5478	>	public final void compute() {
5479	>	final BiFun<? super K, ? super V, ? extends U> transformer;
5480	>	final BiFun<? super U, ? super U, ? extends U> reducer;
5481	>	if ((transformer = this.transformer) != null &&
5482	>	(reducer = this.reducer) != null) {
5483	>	for (int i = baseIndex, f, h; batch > 0 &&
5484	>	(h = ((f = baseLimit) + i) >>> 1) > i;) {
5485	>	addToPendingCount(1);
5486	>	(rights = new MapReduceMappingsTask<K,V,U>
5487	>	(this, batch >>>= 1, baseLimit = h, f, tab,
5488	>	rights, transformer, reducer)).fork();
5489	>	}
5490	>	U r = null;
5491	>	for (Node<K,V> p; (p = advance()) != null; ) {
5492	>	U u;
5493	>	if ((u = transformer.apply(p.key, p.val)) != null)
5494	>	r = (r == null) ? u : reducer.apply(r, u);
5495	>	}
5496	>	result = r;
5497	>	CountedCompleter<?> c;
5498	>	for (c = firstComplete(); c != null; c = c.nextComplete()) {
5499	>	@SuppressWarnings("unchecked") MapReduceMappingsTask<K,V,U>
5500	>	t = (MapReduceMappingsTask<K,V,U>)c,
5501	>	s = t.rights;
5502	>	while (s != null) {
5503	>	U tr, sr;
5504	>	if ((sr = s.result) != null)
5505	>	t.result = (((tr = t.result) == null) ? sr :
5506	>	reducer.apply(tr, sr));
5507	>	s = t.rights = s.nextRight;
5508	>	}
5509	>	}
5510	>	}
5511	>	}
5512	>	}
5513	>
5514	>	@SuppressWarnings("serial")
5515	>	static final class MapReduceKeysToDoubleTask<K,V>
5516	>	extends BulkTask<K,V,Double> {
5517	>	final ObjectToDouble<? super K> transformer;
5518	>	final DoubleByDoubleToDouble reducer;
5519	>	final double basis;
5520	>	double result;
5521	>	MapReduceKeysToDoubleTask<K,V> rights, nextRight;
5522	>	MapReduceKeysToDoubleTask
5523	>	(BulkTask<K,V,?> p, int b, int i, int f, Node<K,V>[] t,
5524	>	MapReduceKeysToDoubleTask<K,V> nextRight,
5525	>	ObjectToDouble<? super K> transformer,
5526	>	double basis,
5527	>	DoubleByDoubleToDouble reducer) {
5528	>	super(p, b, i, f, t); this.nextRight = nextRight;
5529	>	this.transformer = transformer;
5530	>	this.basis = basis; this.reducer = reducer;
5531	>	}
5532	>	public final Double getRawResult() { return result; }
5533	>	public final void compute() {
5534	>	final ObjectToDouble<? super K> transformer;
5535	>	final DoubleByDoubleToDouble reducer;
5536	>	if ((transformer = this.transformer) != null &&
5537	>	(reducer = this.reducer) != null) {
5538	>	double r = this.basis;
5539	>	for (int i = baseIndex, f, h; batch > 0 &&
5540	>	(h = ((f = baseLimit) + i) >>> 1) > i;) {
5541	>	addToPendingCount(1);
5542	>	(rights = new MapReduceKeysToDoubleTask<K,V>
5543	>	(this, batch >>>= 1, baseLimit = h, f, tab,
5544	>	rights, transformer, r, reducer)).fork();
5545	>	}
5546	>	for (Node<K,V> p; (p = advance()) != null; )
5547	>	r = reducer.apply(r, transformer.apply(p.key));
5548	>	result = r;
5549	>	CountedCompleter<?> c;
5550	>	for (c = firstComplete(); c != null; c = c.nextComplete()) {
5551	>	@SuppressWarnings("unchecked") MapReduceKeysToDoubleTask<K,V>
5552	>	t = (MapReduceKeysToDoubleTask<K,V>)c,
5553	>	s = t.rights;
5554	>	while (s != null) {
5555	>	t.result = reducer.apply(t.result, s.result);
5556	>	s = t.rights = s.nextRight;
5557	>	}
5558	>	}
5559	>	}
5560	>	}
5561	>	}
5562	>
5563	>	@SuppressWarnings("serial")
5564	>	static final class MapReduceValuesToDoubleTask<K,V>
5565	>	extends BulkTask<K,V,Double> {
5566	>	final ObjectToDouble<? super V> transformer;
5567	>	final DoubleByDoubleToDouble reducer;
5568	>	final double basis;
5569	>	double result;
5570	>	MapReduceValuesToDoubleTask<K,V> rights, nextRight;
5571	>	MapReduceValuesToDoubleTask
5572	>	(BulkTask<K,V,?> p, int b, int i, int f, Node<K,V>[] t,
5573	>	MapReduceValuesToDoubleTask<K,V> nextRight,
5574	>	ObjectToDouble<? super V> transformer,
5575	>	double basis,
5576	>	DoubleByDoubleToDouble reducer) {
5577	>	super(p, b, i, f, t); this.nextRight = nextRight;
5578	>	this.transformer = transformer;
5579	>	this.basis = basis; this.reducer = reducer;
5580	>	}
5581	>	public final Double getRawResult() { return result; }
5582	>	public final void compute() {
5583	>	final ObjectToDouble<? super V> transformer;
5584	>	final DoubleByDoubleToDouble reducer;
5585	>	if ((transformer = this.transformer) != null &&
5586	>	(reducer = this.reducer) != null) {
5587	>	double r = this.basis;
5588	>	for (int i = baseIndex, f, h; batch > 0 &&
5589	>	(h = ((f = baseLimit) + i) >>> 1) > i;) {
5590	>	addToPendingCount(1);
5591	>	(rights = new MapReduceValuesToDoubleTask<K,V>
5592	>	(this, batch >>>= 1, baseLimit = h, f, tab,
5593	>	rights, transformer, r, reducer)).fork();
5594	>	}
5595	>	for (Node<K,V> p; (p = advance()) != null; )
5596	>	r = reducer.apply(r, transformer.apply(p.val));
5597	>	result = r;
5598	>	CountedCompleter<?> c;
5599	>	for (c = firstComplete(); c != null; c = c.nextComplete()) {
5600	>	@SuppressWarnings("unchecked") MapReduceValuesToDoubleTask<K,V>
5601	>	t = (MapReduceValuesToDoubleTask<K,V>)c,
5602	>	s = t.rights;
5603	>	while (s != null) {
5604	>	t.result = reducer.apply(t.result, s.result);
5605	>	s = t.rights = s.nextRight;
5606	>	}
5607	>	}
5608	>	}
5609	>	}
5610	>	}
5611	>
5612	>	@SuppressWarnings("serial")
5613	>	static final class MapReduceEntriesToDoubleTask<K,V>
5614	>	extends BulkTask<K,V,Double> {
5615	>	final ObjectToDouble<Map.Entry<K,V>> transformer;
5616	>	final DoubleByDoubleToDouble reducer;
5617	>	final double basis;
5618	>	double result;
5619	>	MapReduceEntriesToDoubleTask<K,V> rights, nextRight;
5620	>	MapReduceEntriesToDoubleTask
5621	>	(BulkTask<K,V,?> p, int b, int i, int f, Node<K,V>[] t,
5622	>	MapReduceEntriesToDoubleTask<K,V> nextRight,
5623	>	ObjectToDouble<Map.Entry<K,V>> transformer,
5624	>	double basis,
5625	>	DoubleByDoubleToDouble reducer) {
5626	>	super(p, b, i, f, t); this.nextRight = nextRight;
5627	>	this.transformer = transformer;
5628	>	this.basis = basis; this.reducer = reducer;
5629	>	}
5630	>	public final Double getRawResult() { return result; }
5631	>	public final void compute() {
5632	>	final ObjectToDouble<Map.Entry<K,V>> transformer;
5633	>	final DoubleByDoubleToDouble reducer;
5634	>	if ((transformer = this.transformer) != null &&
5635	>	(reducer = this.reducer) != null) {
5636	>	double r = this.basis;
5637	>	for (int i = baseIndex, f, h; batch > 0 &&
5638	>	(h = ((f = baseLimit) + i) >>> 1) > i;) {
5639	>	addToPendingCount(1);
5640	>	(rights = new MapReduceEntriesToDoubleTask<K,V>
5641	>	(this, batch >>>= 1, baseLimit = h, f, tab,
5642	>	rights, transformer, r, reducer)).fork();
5643	>	}
5644	>	for (Node<K,V> p; (p = advance()) != null; )
5645	>	r = reducer.apply(r, transformer.apply(p));
5646	>	result = r;
5647	>	CountedCompleter<?> c;
5648	>	for (c = firstComplete(); c != null; c = c.nextComplete()) {
5649	>	@SuppressWarnings("unchecked") MapReduceEntriesToDoubleTask<K,V>
5650	>	t = (MapReduceEntriesToDoubleTask<K,V>)c,
5651	>	s = t.rights;
5652	>	while (s != null) {
5653	>	t.result = reducer.apply(t.result, s.result);
5654	>	s = t.rights = s.nextRight;
5655	>	}
5656	>	}
5657	>	}
5658	>	}
5659	>	}
5660	>
5661	>	@SuppressWarnings("serial")
5662	>	static final class MapReduceMappingsToDoubleTask<K,V>
5663	>	extends BulkTask<K,V,Double> {
5664	>	final ObjectByObjectToDouble<? super K, ? super V> transformer;
5665	>	final DoubleByDoubleToDouble reducer;
5666	>	final double basis;
5667	>	double result;
5668	>	MapReduceMappingsToDoubleTask<K,V> rights, nextRight;
5669	>	MapReduceMappingsToDoubleTask
5670	>	(BulkTask<K,V,?> p, int b, int i, int f, Node<K,V>[] t,
5671	>	MapReduceMappingsToDoubleTask<K,V> nextRight,
5672	>	ObjectByObjectToDouble<? super K, ? super V> transformer,
5673	>	double basis,
5674	>	DoubleByDoubleToDouble reducer) {
5675	>	super(p, b, i, f, t); this.nextRight = nextRight;
5676	>	this.transformer = transformer;
5677	>	this.basis = basis; this.reducer = reducer;
5678	>	}
5679	>	public final Double getRawResult() { return result; }
5680	>	public final void compute() {
5681	>	final ObjectByObjectToDouble<? super K, ? super V> transformer;
5682	>	final DoubleByDoubleToDouble reducer;
5683	>	if ((transformer = this.transformer) != null &&
5684	>	(reducer = this.reducer) != null) {
5685	>	double r = this.basis;
5686	>	for (int i = baseIndex, f, h; batch > 0 &&
5687	>	(h = ((f = baseLimit) + i) >>> 1) > i;) {
5688	>	addToPendingCount(1);
5689	>	(rights = new MapReduceMappingsToDoubleTask<K,V>
5690	>	(this, batch >>>= 1, baseLimit = h, f, tab,
5691	>	rights, transformer, r, reducer)).fork();
5692	>	}
5693	>	for (Node<K,V> p; (p = advance()) != null; )
5694	>	r = reducer.apply(r, transformer.apply(p.key, p.val));
5695	>	result = r;
5696	>	CountedCompleter<?> c;
5697	>	for (c = firstComplete(); c != null; c = c.nextComplete()) {
5698	>	@SuppressWarnings("unchecked") MapReduceMappingsToDoubleTask<K,V>
5699	>	t = (MapReduceMappingsToDoubleTask<K,V>)c,
5700	>	s = t.rights;
5701	>	while (s != null) {
5702	>	t.result = reducer.apply(t.result, s.result);
5703	>	s = t.rights = s.nextRight;
5704	>	}
5705	>	}
5706	>	}
5707	>	}
5708	>	}
5709	>
5710	>	@SuppressWarnings("serial")
5711	>	static final class MapReduceKeysToLongTask<K,V>
5712	>	extends BulkTask<K,V,Long> {
5713	>	final ObjectToLong<? super K> transformer;
5714	>	final LongByLongToLong reducer;
5715	>	final long basis;
5716	>	long result;
5717	>	MapReduceKeysToLongTask<K,V> rights, nextRight;
5718	>	MapReduceKeysToLongTask
5719	>	(BulkTask<K,V,?> p, int b, int i, int f, Node<K,V>[] t,
5720	>	MapReduceKeysToLongTask<K,V> nextRight,
5721	>	ObjectToLong<? super K> transformer,
5722	>	long basis,
5723	>	LongByLongToLong reducer) {
5724	>	super(p, b, i, f, t); this.nextRight = nextRight;
5725	>	this.transformer = transformer;
5726	>	this.basis = basis; this.reducer = reducer;
5727	>	}
5728	>	public final Long getRawResult() { return result; }
5729	>	public final void compute() {
5730	>	final ObjectToLong<? super K> transformer;
5731	>	final LongByLongToLong reducer;
5732	>	if ((transformer = this.transformer) != null &&
5733	>	(reducer = this.reducer) != null) {
5734	>	long r = this.basis;
5735	>	for (int i = baseIndex, f, h; batch > 0 &&
5736	>	(h = ((f = baseLimit) + i) >>> 1) > i;) {
5737	>	addToPendingCount(1);
5738	>	(rights = new MapReduceKeysToLongTask<K,V>
5739	>	(this, batch >>>= 1, baseLimit = h, f, tab,
5740	>	rights, transformer, r, reducer)).fork();
5741	>	}
5742	>	for (Node<K,V> p; (p = advance()) != null; )
5743	>	r = reducer.apply(r, transformer.apply(p.key));
5744	>	result = r;
5745	>	CountedCompleter<?> c;
5746	>	for (c = firstComplete(); c != null; c = c.nextComplete()) {
5747	>	@SuppressWarnings("unchecked") MapReduceKeysToLongTask<K,V>
5748	>	t = (MapReduceKeysToLongTask<K,V>)c,
5749	>	s = t.rights;
5750	>	while (s != null) {
5751	>	t.result = reducer.apply(t.result, s.result);
5752	>	s = t.rights = s.nextRight;
5753	>	}
5754	>	}
5755	>	}
5756	>	}
5757	>	}
5758	>
5759	>	@SuppressWarnings("serial")
5760	>	static final class MapReduceValuesToLongTask<K,V>
5761	>	extends BulkTask<K,V,Long> {
5762	>	final ObjectToLong<? super V> transformer;
5763	>	final LongByLongToLong reducer;
5764	>	final long basis;
5765	>	long result;
5766	>	MapReduceValuesToLongTask<K,V> rights, nextRight;
5767	>	MapReduceValuesToLongTask
5768	>	(BulkTask<K,V,?> p, int b, int i, int f, Node<K,V>[] t,
5769	>	MapReduceValuesToLongTask<K,V> nextRight,
5770	>	ObjectToLong<? super V> transformer,
5771	>	long basis,
5772	>	LongByLongToLong reducer) {
5773	>	super(p, b, i, f, t); this.nextRight = nextRight;
5774	>	this.transformer = transformer;
5775	>	this.basis = basis; this.reducer = reducer;
5776	>	}
5777	>	public final Long getRawResult() { return result; }
5778	>	public final void compute() {
5779	>	final ObjectToLong<? super V> transformer;
5780	>	final LongByLongToLong reducer;
5781	>	if ((transformer = this.transformer) != null &&
5782	>	(reducer = this.reducer) != null) {
5783	>	long r = this.basis;
5784	>	for (int i = baseIndex, f, h; batch > 0 &&
5785	>	(h = ((f = baseLimit) + i) >>> 1) > i;) {
5786	>	addToPendingCount(1);
5787	>	(rights = new MapReduceValuesToLongTask<K,V>
5788	>	(this, batch >>>= 1, baseLimit = h, f, tab,
5789	>	rights, transformer, r, reducer)).fork();
5790	>	}
5791	>	for (Node<K,V> p; (p = advance()) != null; )
5792	>	r = reducer.apply(r, transformer.apply(p.val));
5793	>	result = r;
5794	>	CountedCompleter<?> c;
5795	>	for (c = firstComplete(); c != null; c = c.nextComplete()) {
5796	>	@SuppressWarnings("unchecked") MapReduceValuesToLongTask<K,V>
5797	>	t = (MapReduceValuesToLongTask<K,V>)c,
5798	>	s = t.rights;
5799	>	while (s != null) {
5800	>	t.result = reducer.apply(t.result, s.result);
5801	>	s = t.rights = s.nextRight;
5802	>	}
5803	>	}
5804	>	}
5805	>	}
5806	>	}
5807	>
5808	>	@SuppressWarnings("serial")
5809	>	static final class MapReduceEntriesToLongTask<K,V>
5810	>	extends BulkTask<K,V,Long> {
5811	>	final ObjectToLong<Map.Entry<K,V>> transformer;
5812	>	final LongByLongToLong reducer;
5813	>	final long basis;
5814	>	long result;
5815	>	MapReduceEntriesToLongTask<K,V> rights, nextRight;
5816	>	MapReduceEntriesToLongTask
5817	>	(BulkTask<K,V,?> p, int b, int i, int f, Node<K,V>[] t,
5818	>	MapReduceEntriesToLongTask<K,V> nextRight,
5819	>	ObjectToLong<Map.Entry<K,V>> transformer,
5820	>	long basis,
5821	>	LongByLongToLong reducer) {
5822	>	super(p, b, i, f, t); this.nextRight = nextRight;
5823	>	this.transformer = transformer;
5824	>	this.basis = basis; this.reducer = reducer;
5825	>	}
5826	>	public final Long getRawResult() { return result; }
5827	>	public final void compute() {
5828	>	final ObjectToLong<Map.Entry<K,V>> transformer;
5829	>	final LongByLongToLong reducer;
5830	>	if ((transformer = this.transformer) != null &&
5831	>	(reducer = this.reducer) != null) {
5832	>	long r = this.basis;
5833	>	for (int i = baseIndex, f, h; batch > 0 &&
5834	>	(h = ((f = baseLimit) + i) >>> 1) > i;) {
5835	>	addToPendingCount(1);
5836	>	(rights = new MapReduceEntriesToLongTask<K,V>
5837	>	(this, batch >>>= 1, baseLimit = h, f, tab,
5838	>	rights, transformer, r, reducer)).fork();
5839	>	}
5840	>	for (Node<K,V> p; (p = advance()) != null; )
5841	>	r = reducer.apply(r, transformer.apply(p));
5842	>	result = r;
5843	>	CountedCompleter<?> c;
5844	>	for (c = firstComplete(); c != null; c = c.nextComplete()) {
5845	>	@SuppressWarnings("unchecked") MapReduceEntriesToLongTask<K,V>
5846	>	t = (MapReduceEntriesToLongTask<K,V>)c,
5847	>	s = t.rights;
5848	>	while (s != null) {
5849	>	t.result = reducer.apply(t.result, s.result);
5850	>	s = t.rights = s.nextRight;
5851	>	}
5852	>	}
5853	>	}
5854	>	}
5855	>	}
5856	>
5857	>	@SuppressWarnings("serial")
5858	>	static final class MapReduceMappingsToLongTask<K,V>
5859	>	extends BulkTask<K,V,Long> {
5860	>	final ObjectByObjectToLong<? super K, ? super V> transformer;
5861	>	final LongByLongToLong reducer;
5862	>	final long basis;
5863	>	long result;
5864	>	MapReduceMappingsToLongTask<K,V> rights, nextRight;
5865	>	MapReduceMappingsToLongTask
5866	>	(BulkTask<K,V,?> p, int b, int i, int f, Node<K,V>[] t,
5867	>	MapReduceMappingsToLongTask<K,V> nextRight,
5868	>	ObjectByObjectToLong<? super K, ? super V> transformer,
5869	>	long basis,
5870	>	LongByLongToLong reducer) {
5871	>	super(p, b, i, f, t); this.nextRight = nextRight;
5872	>	this.transformer = transformer;
5873	>	this.basis = basis; this.reducer = reducer;
5874	>	}
5875	>	public final Long getRawResult() { return result; }
5876	>	public final void compute() {
5877	>	final ObjectByObjectToLong<? super K, ? super V> transformer;
5878	>	final LongByLongToLong reducer;
5879	>	if ((transformer = this.transformer) != null &&
5880	>	(reducer = this.reducer) != null) {
5881	>	long r = this.basis;
5882	>	for (int i = baseIndex, f, h; batch > 0 &&
5883	>	(h = ((f = baseLimit) + i) >>> 1) > i;) {
5884	>	addToPendingCount(1);
5885	>	(rights = new MapReduceMappingsToLongTask<K,V>
5886	>	(this, batch >>>= 1, baseLimit = h, f, tab,
5887	>	rights, transformer, r, reducer)).fork();
5888	>	}
5889	>	for (Node<K,V> p; (p = advance()) != null; )
5890	>	r = reducer.apply(r, transformer.apply(p.key, p.val));
5891	>	result = r;
5892	>	CountedCompleter<?> c;
5893	>	for (c = firstComplete(); c != null; c = c.nextComplete()) {
5894	>	@SuppressWarnings("unchecked") MapReduceMappingsToLongTask<K,V>
5895	>	t = (MapReduceMappingsToLongTask<K,V>)c,
5896	>	s = t.rights;
5897	>	while (s != null) {
5898	>	t.result = reducer.apply(t.result, s.result);
5899	>	s = t.rights = s.nextRight;
5900	>	}
5901	>	}
5902	>	}
5903	>	}
5904	>	}
5905	>
5906	>	@SuppressWarnings("serial")
5907	>	static final class MapReduceKeysToIntTask<K,V>
5908	>	extends BulkTask<K,V,Integer> {
5909	>	final ObjectToInt<? super K> transformer;
5910	>	final IntByIntToInt reducer;
5911	>	final int basis;
5912	>	int result;
5913	>	MapReduceKeysToIntTask<K,V> rights, nextRight;
5914	>	MapReduceKeysToIntTask
5915	>	(BulkTask<K,V,?> p, int b, int i, int f, Node<K,V>[] t,
5916	>	MapReduceKeysToIntTask<K,V> nextRight,
5917	>	ObjectToInt<? super K> transformer,
5918	>	int basis,
5919	>	IntByIntToInt reducer) {
5920	>	super(p, b, i, f, t); this.nextRight = nextRight;
5921	>	this.transformer = transformer;
5922	>	this.basis = basis; this.reducer = reducer;
5923	>	}
5924	>	public final Integer getRawResult() { return result; }
5925	>	public final void compute() {
5926	>	final ObjectToInt<? super K> transformer;
5927	>	final IntByIntToInt reducer;
5928	>	if ((transformer = this.transformer) != null &&
5929	>	(reducer = this.reducer) != null) {
5930	>	int r = this.basis;
5931	>	for (int i = baseIndex, f, h; batch > 0 &&
5932	>	(h = ((f = baseLimit) + i) >>> 1) > i;) {
5933	>	addToPendingCount(1);
5934	>	(rights = new MapReduceKeysToIntTask<K,V>
5935	>	(this, batch >>>= 1, baseLimit = h, f, tab,
5936	>	rights, transformer, r, reducer)).fork();
5937	>	}
5938	>	for (Node<K,V> p; (p = advance()) != null; )
5939	>	r = reducer.apply(r, transformer.apply(p.key));
5940	>	result = r;
5941	>	CountedCompleter<?> c;
5942	>	for (c = firstComplete(); c != null; c = c.nextComplete()) {
5943	>	@SuppressWarnings("unchecked") MapReduceKeysToIntTask<K,V>
5944	>	t = (MapReduceKeysToIntTask<K,V>)c,
5945	>	s = t.rights;
5946	>	while (s != null) {
5947	>	t.result = reducer.apply(t.result, s.result);
5948	>	s = t.rights = s.nextRight;
5949	>	}
5950	>	}
5951	>	}
5952	>	}
5953	>	}
5954	>
5955	>	@SuppressWarnings("serial")
5956	>	static final class MapReduceValuesToIntTask<K,V>
5957	>	extends BulkTask<K,V,Integer> {
5958	>	final ObjectToInt<? super V> transformer;
5959	>	final IntByIntToInt reducer;
5960	>	final int basis;
5961	>	int result;
5962	>	MapReduceValuesToIntTask<K,V> rights, nextRight;
5963	>	MapReduceValuesToIntTask
5964	>	(BulkTask<K,V,?> p, int b, int i, int f, Node<K,V>[] t,
5965	>	MapReduceValuesToIntTask<K,V> nextRight,
5966	>	ObjectToInt<? super V> transformer,
5967	>	int basis,
5968	>	IntByIntToInt reducer) {
5969	>	super(p, b, i, f, t); this.nextRight = nextRight;
5970	>	this.transformer = transformer;
5971	>	this.basis = basis; this.reducer = reducer;
5972	>	}
5973	>	public final Integer getRawResult() { return result; }
5974	>	public final void compute() {
5975	>	final ObjectToInt<? super V> transformer;
5976	>	final IntByIntToInt reducer;
5977	>	if ((transformer = this.transformer) != null &&
5978	>	(reducer = this.reducer) != null) {
5979	>	int r = this.basis;
5980	>	for (int i = baseIndex, f, h; batch > 0 &&
5981	>	(h = ((f = baseLimit) + i) >>> 1) > i;) {
5982	>	addToPendingCount(1);
5983	>	(rights = new MapReduceValuesToIntTask<K,V>
5984	>	(this, batch >>>= 1, baseLimit = h, f, tab,
5985	>	rights, transformer, r, reducer)).fork();
5986	>	}
5987	>	for (Node<K,V> p; (p = advance()) != null; )
5988	>	r = reducer.apply(r, transformer.apply(p.val));
5989	>	result = r;
5990	>	CountedCompleter<?> c;
5991	>	for (c = firstComplete(); c != null; c = c.nextComplete()) {
5992	>	@SuppressWarnings("unchecked") MapReduceValuesToIntTask<K,V>
5993	>	t = (MapReduceValuesToIntTask<K,V>)c,
5994	>	s = t.rights;
5995	>	while (s != null) {
5996	>	t.result = reducer.apply(t.result, s.result);
5997	>	s = t.rights = s.nextRight;
5998	>	}
5999	>	}
6000	>	}
6001	>	}
6002	>	}
6003	>
6004	>	@SuppressWarnings("serial")
6005	>	static final class MapReduceEntriesToIntTask<K,V>
6006	>	extends BulkTask<K,V,Integer> {
6007	>	final ObjectToInt<Map.Entry<K,V>> transformer;
6008	>	final IntByIntToInt reducer;
6009	>	final int basis;
6010	>	int result;
6011	>	MapReduceEntriesToIntTask<K,V> rights, nextRight;
6012	>	MapReduceEntriesToIntTask
6013	>	(BulkTask<K,V,?> p, int b, int i, int f, Node<K,V>[] t,
6014	>	MapReduceEntriesToIntTask<K,V> nextRight,
6015	>	ObjectToInt<Map.Entry<K,V>> transformer,
6016	>	int basis,
6017	>	IntByIntToInt reducer) {
6018	>	super(p, b, i, f, t); this.nextRight = nextRight;
6019	>	this.transformer = transformer;
6020	>	this.basis = basis; this.reducer = reducer;
6021	>	}
6022	>	public final Integer getRawResult() { return result; }
6023	>	public final void compute() {
6024	>	final ObjectToInt<Map.Entry<K,V>> transformer;
6025	>	final IntByIntToInt reducer;
6026	>	if ((transformer = this.transformer) != null &&
6027	>	(reducer = this.reducer) != null) {
6028	>	int r = this.basis;
6029	>	for (int i = baseIndex, f, h; batch > 0 &&
6030	>	(h = ((f = baseLimit) + i) >>> 1) > i;) {
6031	>	addToPendingCount(1);
6032	>	(rights = new MapReduceEntriesToIntTask<K,V>
6033	>	(this, batch >>>= 1, baseLimit = h, f, tab,
6034	>	rights, transformer, r, reducer)).fork();
6035	>	}
6036	>	for (Node<K,V> p; (p = advance()) != null; )
6037	>	r = reducer.apply(r, transformer.apply(p));
6038	>	result = r;
6039	>	CountedCompleter<?> c;
6040	>	for (c = firstComplete(); c != null; c = c.nextComplete()) {
6041	>	@SuppressWarnings("unchecked") MapReduceEntriesToIntTask<K,V>
6042	>	t = (MapReduceEntriesToIntTask<K,V>)c,
6043	>	s = t.rights;
6044	>	while (s != null) {
6045	>	t.result = reducer.apply(t.result, s.result);
6046	>	s = t.rights = s.nextRight;
6047	>	}
6048	>	}
6049	>	}
6050	>	}
6051	>	}
6052	>
6053	>	@SuppressWarnings("serial")
6054	>	static final class MapReduceMappingsToIntTask<K,V>
6055	>	extends BulkTask<K,V,Integer> {
6056	>	final ObjectByObjectToInt<? super K, ? super V> transformer;
6057	>	final IntByIntToInt reducer;
6058	>	final int basis;
6059	>	int result;
6060	>	MapReduceMappingsToIntTask<K,V> rights, nextRight;
6061	>	MapReduceMappingsToIntTask
6062	>	(BulkTask<K,V,?> p, int b, int i, int f, Node<K,V>[] t,
6063	>	MapReduceMappingsToIntTask<K,V> nextRight,
6064	>	ObjectByObjectToInt<? super K, ? super V> transformer,
6065	>	int basis,
6066	>	IntByIntToInt reducer) {
6067	>	super(p, b, i, f, t); this.nextRight = nextRight;
6068	>	this.transformer = transformer;
6069	>	this.basis = basis; this.reducer = reducer;
6070	>	}
6071	>	public final Integer getRawResult() { return result; }
6072	>	public final void compute() {
6073	>	final ObjectByObjectToInt<? super K, ? super V> transformer;
6074	>	final IntByIntToInt reducer;
6075	>	if ((transformer = this.transformer) != null &&
6076	>	(reducer = this.reducer) != null) {
6077	>	int r = this.basis;
6078	>	for (int i = baseIndex, f, h; batch > 0 &&
6079	>	(h = ((f = baseLimit) + i) >>> 1) > i;) {
6080	>	addToPendingCount(1);
6081	>	(rights = new MapReduceMappingsToIntTask<K,V>
6082	>	(this, batch >>>= 1, baseLimit = h, f, tab,
6083	>	rights, transformer, r, reducer)).fork();
6084	>	}
6085	>	for (Node<K,V> p; (p = advance()) != null; )
6086	>	r = reducer.apply(r, transformer.apply(p.key, p.val));
6087	>	result = r;
6088	>	CountedCompleter<?> c;
6089	>	for (c = firstComplete(); c != null; c = c.nextComplete()) {
6090	>	@SuppressWarnings("unchecked") MapReduceMappingsToIntTask<K,V>
6091	>	t = (MapReduceMappingsToIntTask<K,V>)c,
6092	>	s = t.rights;
6093	>	while (s != null) {
6094	>	t.result = reducer.apply(t.result, s.result);
6095	>	s = t.rights = s.nextRight;
6096	>	}
6097	>	}
6098	>	}
6099	>	}
6100	>	}
6101	>
6102	>	/* ---------------- Counters -------------- */
6103	>
6104	>	// Adapted from LongAdder and Striped64.
6105	>	// See their internal docs for explanation.
6106	>
6107	>	// A padded cell for distributing counts
6108	>	static final class CounterCell {
6109	>	volatile long p0, p1, p2, p3, p4, p5, p6;
6110	>	volatile long value;
6111	>	volatile long q0, q1, q2, q3, q4, q5, q6;
6112	>	CounterCell(long x) { value = x; }
6113	>	}
6114	>
6115	>	/**
6116	>	* Holder for the thread-local hash code determining which
6117	>	* CounterCell to use. The code is initialized via the
6118	>	* counterHashCodeGenerator, but may be moved upon collisions.
6119	>	*/
6120	>	static final class CounterHashCode {
6121	>	int code;
6122	>	}
6123	>
6124	>	/**
6125	>	* Generates initial value for per-thread CounterHashCodes.
6126	>	*/
6127	>	static final AtomicInteger counterHashCodeGenerator = new AtomicInteger();
6128	>
6129	>	/**
6130	>	* Increment for counterHashCodeGenerator. See class ThreadLocal
6131	>	* for explanation.
6132	>	*/
6133	>	static final int SEED_INCREMENT = 0x61c88647;
6134	>
6135	>	/**
6136	>	* Per-thread counter hash codes. Shared across all instances.
6137	>	*/
6138	>	static final ThreadLocal<CounterHashCode> threadCounterHashCode =
6139	>	new ThreadLocal<CounterHashCode>();
6140	>
6141	>
6142	>	final long sumCount() {
6143	>	CounterCell[] as = counterCells; CounterCell a;
6144	>	long sum = baseCount;
6145	>	if (as != null) {
6146	>	for (int i = 0; i < as.length; ++i) {
6147	>	if ((a = as[i]) != null)
6148	>	sum += a.value;
6149	>	}
6150	>	}
6151	>	return sum;
6152	>	}
6153	>
6154	>	// See LongAdder version for explanation
6155	>	private final void fullAddCount(long x, CounterHashCode hc,
6156	>	boolean wasUncontended) {
6157	>	int h;
6158	>	if (hc == null) {
6159	>	hc = new CounterHashCode();
6160	>	int s = counterHashCodeGenerator.addAndGet(SEED_INCREMENT);
6161	>	h = hc.code = (s == 0) ? 1 : s; // Avoid zero
6162	>	threadCounterHashCode.set(hc);
6163	>	}
6164	>	else
6165	>	h = hc.code;
6166	>	boolean collide = false;                // True if last slot nonempty
6167	>	for (;;) {
6168	>	CounterCell[] as; CounterCell a; int n; long v;
6169	>	if ((as = counterCells) != null && (n = as.length) > 0) {
6170	>	if ((a = as[(n - 1) & h]) == null) {
6171	>	if (cellsBusy == 0) {            // Try to attach new Cell
6172	>	CounterCell r = new CounterCell(x); // Optimistic create
6173	>	if (cellsBusy == 0 &&
6174	>	U.compareAndSwapInt(this, CELLSBUSY, 0, 1)) {
6175	>	boolean created = false;
6176	>	try {               // Recheck under lock
6177	>	CounterCell[] rs; int m, j;
6178	>	if ((rs = counterCells) != null &&
6179	>	(m = rs.length) > 0 &&
6180	>	rs[j = (m - 1) & h] == null) {
6181	>	rs[j] = r;
6182	>	created = true;
6183	>	}
6184	>	} finally {
6185	>	cellsBusy = 0;
6186	>	}
6187	>	if (created)
6188	>	break;
6189	>	continue;           // Slot is now non-empty
6190		}
3267	–	table = tab;
3268	–	counter.add(size);
3269	–	sc = n - (n >>> 2);
6191		}
6192	<	} finally {
3272	<	sizeCtl = sc;
6192	>	collide = false;
6193		}
6194	<	if (collide) { // rescan and convert to TreeBins
6195	<	Node[] tab = table;
6196	<	for (int i = 0; i < tab.length; ++i) {
6197	<	int c = 0;
6198	<	for (Node e = tabAt(tab, i); e != null; e = e.next) {
6199	<	if (++c > TREE_THRESHOLD &&
6200	<	(e.key instanceof Comparable)) {
6201	<	replaceWithTreeBin(tab, i, e.key);
6202	<	break;
6203	<	}
6194	>	else if (!wasUncontended)       // CAS already known to fail
6195	>	wasUncontended = true;      // Continue after rehash
6196	>	else if (U.compareAndSwapLong(a, CELLVALUE, v = a.value, v + x))
6197	>	break;
6198	>	else if (counterCells != as || n >= NCPU)
6199	>	collide = false;            // At max size or stale
6200	>	else if (!collide)
6201	>	collide = true;
6202	>	else if (cellsBusy == 0 &&
6203	>	U.compareAndSwapInt(this, CELLSBUSY, 0, 1)) {
6204	>	try {
6205	>	if (counterCells == as) {// Expand table unless stale
6206	>	CounterCell[] rs = new CounterCell[n << 1];
6207	>	for (int i = 0; i < n; ++i)
6208	>	rs[i] = as[i];
6209	>	counterCells = rs;
6210		}
6211	+	} finally {
6212	+	cellsBusy = 0;
6213		}
6214	+	collide = false;
6215	+	continue;                   // Retry with expanded table
6216		}
6217	<	}
6218	<	if (!init) { // Can only happen if unsafely published.
6219	<	while (p != null) {
6220	<	internalPut(p.key, p.val);
6221	<	p = p.next;
6217	>	h ^= h << 13;                   // Rehash
6218	>	h ^= h >>> 17;
6219	>	h ^= h << 5;
6220	>	}
6221	>	else if (cellsBusy == 0 && counterCells == as &&
6222	>	U.compareAndSwapInt(this, CELLSBUSY, 0, 1)) {
6223	>	boolean init = false;
6224	>	try {                           // Initialize table
6225	>	if (counterCells == as) {
6226	>	CounterCell[] rs = new CounterCell[2];
6227	>	rs[h & 1] = new CounterCell(x);
6228	>	counterCells = rs;
6229	>	init = true;
6230	>	}
6231	>	} finally {
6232	>	cellsBusy = 0;
6233		}
6234	+	if (init)
6235	+	break;
6236		}
6237	+	else if (U.compareAndSwapLong(this, BASECOUNT, v = baseCount, v + x))
6238	+	break;                          // Fall back on using base
6239		}
6240	+	hc.code = h;                            // Record index for next time
6241		}
6242
6243		// Unsafe mechanics
6244	<	private static final sun.misc.Unsafe UNSAFE;
6245	<	private static final long counterOffset;
6246	<	private static final long sizeCtlOffset;
6244	>	private static final sun.misc.Unsafe U;
6245	>	private static final long SIZECTL;
6246	>	private static final long TRANSFERINDEX;
6247	>	private static final long BASECOUNT;
6248	>	private static final long CELLSBUSY;
6249	>	private static final long CELLVALUE;
6250		private static final long ABASE;
6251		private static final int ASHIFT;
6252
6253		static {
3305	–	int ss;
6254		try {
6255	<	UNSAFE = getUnsafe();
6255	>	U = getUnsafe();
6256		Class<?> k = ConcurrentHashMapV8.class;
6257	<	counterOffset = UNSAFE.objectFieldOffset
3310	<	(k.getDeclaredField("counter"));
3311	<	sizeCtlOffset = UNSAFE.objectFieldOffset
6257	>	SIZECTL = U.objectFieldOffset
6258		(k.getDeclaredField("sizeCtl"));
6259	<	Class<?> sc = Node[].class;
6260	<	ABASE = UNSAFE.arrayBaseOffset(sc);
6261	<	ss = UNSAFE.arrayIndexScale(sc);
6259	>	TRANSFERINDEX = U.objectFieldOffset
6260	>	(k.getDeclaredField("transferIndex"));
6261	>	BASECOUNT = U.objectFieldOffset
6262	>	(k.getDeclaredField("baseCount"));
6263	>	CELLSBUSY = U.objectFieldOffset
6264	>	(k.getDeclaredField("cellsBusy"));
6265	>	Class<?> ck = CounterCell.class;
6266	>	CELLVALUE = U.objectFieldOffset
6267	>	(ck.getDeclaredField("value"));
6268	>	Class<?> ak = Node[].class;
6269	>	ABASE = U.arrayBaseOffset(ak);
6270	>	int scale = U.arrayIndexScale(ak);
6271	>	if ((scale & (scale - 1)) != 0)
6272	>	throw new Error("data type scale not a power of two");
6273	>	ASHIFT = 31 - Integer.numberOfLeadingZeros(scale);
6274		} catch (Exception e) {
6275		throw new Error(e);
6276		}
3319	–	if ((ss & (ss-1)) != 0)
3320	–	throw new Error("data type scale not a power of two");
3321	–	ASHIFT = 31 - Integer.numberOfLeadingZeros(ss);
6277		}
6278
6279		/**
#	Line 3331 | Line 6286 | public class ConcurrentHashMapV8<K, V>
6286		private static sun.misc.Unsafe getUnsafe() {
6287		try {
6288		return sun.misc.Unsafe.getUnsafe();
6289	<	} catch (SecurityException se) {
6290	<	try {
6291	<	return java.security.AccessController.doPrivileged
6292	<	(new java.security
6293	<	.PrivilegedExceptionAction<sun.misc.Unsafe>() {
6294	<	public sun.misc.Unsafe run() throws Exception {
6295	<	java.lang.reflect.Field f = sun.misc
6296	<	.Unsafe.class.getDeclaredField("theUnsafe");
6297	<	f.setAccessible(true);
6298	<	return (sun.misc.Unsafe) f.get(null);
6299	<	}});
6300	<	} catch (java.security.PrivilegedActionException e) {
6301	<	throw new RuntimeException("Could not initialize intrinsics",
6302	<	e.getCause());
6303	<	}
6289	>	} catch (SecurityException tryReflectionInstead) {}
6290	>	try {
6291	>	return java.security.AccessController.doPrivileged
6292	>	(new java.security.PrivilegedExceptionAction<sun.misc.Unsafe>() {
6293	>	public sun.misc.Unsafe run() throws Exception {
6294	>	Class<sun.misc.Unsafe> k = sun.misc.Unsafe.class;
6295	>	for (java.lang.reflect.Field f : k.getDeclaredFields()) {
6296	>	f.setAccessible(true);
6297	>	Object x = f.get(null);
6298	>	if (k.isInstance(x))
6299	>	return k.cast(x);
6300	>	}
6301	>	throw new NoSuchFieldError("the Unsafe");
6302	>	}});
6303	>	} catch (java.security.PrivilegedActionException e) {
6304	>	throw new RuntimeException("Could not initialize intrinsics",
6305	>	e.getCause());
6306		}
6307		}
3351	–
6308		}

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