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Comparing jsr166/src/jsr166e/ConcurrentHashMapV8.java (file contents):
Revision 1.13 by jsr166, Wed Aug 31 00:22:11 2011 UTC vs.
Revision 1.111 by jsr166, Fri Jul 19 19:34:43 2013 UTC

#	Line 5 | Line 5
5		*/
6
7		package jsr166e;
8	<	import jsr166e.LongAdder;
9	<	import java.util.Map;
10	<	import java.util.Set;
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.Arrays;
16		import java.util.Collection;
17	<	import java.util.AbstractMap;
18	<	import java.util.AbstractSet;
19	<	import java.util.AbstractCollection;
15	<	import java.util.Hashtable;
17	>	import java.util.Comparator;
18	>	import java.util.ConcurrentModificationException;
19	>	import java.util.Enumeration;
20		import java.util.HashMap;
21	+	import java.util.Hashtable;
22		import java.util.Iterator;
23	<	import java.util.Enumeration;
19	<	import java.util.ConcurrentModificationException;
23	>	import java.util.Map;
24		import java.util.NoSuchElementException;
25	+	import java.util.Set;
26		import java.util.concurrent.ConcurrentMap;
27	<	import java.io.Serializable;
27	>	import java.util.concurrent.atomic.AtomicReference;
28	>	import java.util.concurrent.atomic.AtomicInteger;
29	>	import java.util.concurrent.locks.LockSupport;
30	>	import java.util.concurrent.locks.ReentrantLock;
31
32		/**
33		* A hash table supporting full concurrency of retrievals and
#	Line 33 | Line 41 | import java.io.Serializable;
41		* interoperable with {@code Hashtable} in programs that rely on its
42		* thread safety but not on its synchronization details.
43		*
44	<	* <p> Retrieval operations (including {@code get}) generally do not
44	>	* <p>Retrieval operations (including {@code get}) generally do not
45		* block, so may overlap with update operations (including {@code put}
46		* and {@code remove}). Retrievals reflect the results of the most
47		* recently <em>completed</em> update operations holding upon their
48	<	* onset.  For aggregate operations such as {@code putAll} and {@code
49	<	* clear}, concurrent retrievals may reflect insertion or removal of
50	<	* only some entries.  Similarly, Iterators and Enumerations return
51	<	* elements reflecting the state of the hash table at some point at or
52	<	* since the creation of the iterator/enumeration.  They do
53	<	* <em>not</em> throw {@link ConcurrentModificationException}.
54	<	* However, iterators are designed to be used by only one thread at a
55	<	* time.  Bear in mind that the results of aggregate status methods
56	<	* including {@code size}, {@code isEmpty}, and {@code containsValue}
57	<	* are typically useful only when a map is not undergoing concurrent
58	<	* updates in other threads.  Otherwise the results of these methods
59	<	* reflect transient states that may be adequate for monitoring
60	<	* purposes, but not for program control.
61	<	*
62	<	* <p> Resizing this or any other kind of hash table is a relatively
63	<	* slow operation, so, when possible, it is a good idea to provide
64	<	* estimates of expected table sizes in constructors. Also, for
65	<	* compatibility with previous versions of this class, constructors
66	<	* may optionally specify an expected {@code concurrencyLevel} as an
67	<	* additional hint for internal sizing.
48	>	* onset. (More formally, an update operation for a given key bears a
49	>	* <em>happens-before</em> relation with any (non-null) retrieval for
50	>	* that key reporting the updated value.)  For aggregate operations
51	>	* such as {@code putAll} and {@code clear}, concurrent retrievals may
52	>	* reflect insertion or removal of only some entries.  Similarly,
53	>	* Iterators and Enumerations return elements reflecting the state of
54	>	* the hash table at some point at or since the creation of the
55	>	* iterator/enumeration.  They do <em>not</em> throw {@link
56	>	* ConcurrentModificationException}.  However, iterators are designed
57	>	* to be used by only one thread at a time.  Bear in mind that the
58	>	* results of aggregate status methods including {@code size}, {@code
59	>	* isEmpty}, and {@code containsValue} are typically useful only when
60	>	* a map is not undergoing concurrent updates in other threads.
61	>	* Otherwise the results of these methods reflect transient states
62	>	* that may be adequate for monitoring or estimation purposes, but not
63	>	* for program control.
64	>	*
65	>	* <p>The table is dynamically expanded when there are too many
66	>	* collisions (i.e., keys that have distinct hash codes but fall into
67	>	* the same slot modulo the table size), with the expected average
68	>	* effect of maintaining roughly two bins per mapping (corresponding
69	>	* to a 0.75 load factor threshold for resizing). There may be much
70	>	* variance around this average as mappings are added and removed, but
71	>	* overall, this maintains a commonly accepted time/space tradeoff for
72	>	* hash tables.  However, resizing this or any other kind of hash
73	>	* table may be a relatively slow operation. When possible, it is a
74	>	* good idea to provide a size estimate as an optional {@code
75	>	* initialCapacity} constructor argument. An additional optional
76	>	* {@code loadFactor} constructor argument provides a further means of
77	>	* customizing initial table capacity by specifying the table density
78	>	* to be used in calculating the amount of space to allocate for the
79	>	* given number of elements.  Also, for compatibility with previous
80	>	* versions of this class, constructors may optionally specify an
81	>	* expected {@code concurrencyLevel} as an additional hint for
82	>	* internal sizing.  Note that using many keys with exactly the same
83	>	* {@code hashCode()} is a sure way to slow down performance of any
84	>	* hash table. To ameliorate impact, when keys are {@link Comparable},
85	>	* this class may use comparison order among keys to help break ties.
86	>	*
87	>	* <p>A {@link Set} projection of a ConcurrentHashMapV8 may be created
88	>	* (using {@link #newKeySet()} or {@link #newKeySet(int)}), or viewed
89	>	* (using {@link #keySet(Object)} when only keys are of interest, and the
90	>	* mapped values are (perhaps transiently) not used or all take the
91	>	* same mapping value.
92		*
93		* <p>This class and its views and iterators implement all of the
94		* <em>optional</em> methods of the {@link Map} and {@link Iterator}
95		* interfaces.
96		*
97	<	* <p> Like {@link Hashtable} but unlike {@link HashMap}, this class
97	>	* <p>Like {@link Hashtable} but unlike {@link HashMap}, this class
98		* does <em>not</em> allow {@code null} to be used as a key or value.
99		*
100	+	* <p>ConcurrentHashMapV8s support a set of sequential and parallel bulk
101	+	* operations that are designed
102	+	* to be safely, and often sensibly, applied even with maps that are
103	+	* being concurrently updated by other threads; for example, when
104	+	* computing a snapshot summary of the values in a shared registry.
105	+	* There are three kinds of operation, each with four forms, accepting
106	+	* functions with Keys, Values, Entries, and (Key, Value) arguments
107	+	* and/or return values. Because the elements of a ConcurrentHashMapV8
108	+	* are not ordered in any particular way, and may be processed in
109	+	* different orders in different parallel executions, the correctness
110	+	* of supplied functions should not depend on any ordering, or on any
111	+	* other objects or values that may transiently change while
112	+	* computation is in progress; and except for forEach actions, should
113	+	* ideally be side-effect-free. Bulk operations on {@link java.util.Map.Entry}
114	+	* objects do not support method {@code setValue}.
115	+	*
116	+	* <ul>
117	+	* <li> forEach: Perform a given action on each element.
118	+	* A variant form applies a given transformation on each element
119	+	* before performing the action.</li>
120	+	*
121	+	* <li> search: Return the first available non-null result of
122	+	* applying a given function on each element; skipping further
123	+	* search when a result is found.</li>
124	+	*
125	+	* <li> reduce: Accumulate each element.  The supplied reduction
126	+	* function cannot rely on ordering (more formally, it should be
127	+	* both associative and commutative).  There are five variants:
128	+	*
129	+	* <ul>
130	+	*
131	+	* <li> Plain reductions. (There is not a form of this method for
132	+	* (key, value) function arguments since there is no corresponding
133	+	* return type.)</li>
134	+	*
135	+	* <li> Mapped reductions that accumulate the results of a given
136	+	* function applied to each element.</li>
137	+	*
138	+	* <li> Reductions to scalar doubles, longs, and ints, using a
139	+	* given basis value.</li>
140	+	*
141	+	* </ul>
142	+	* </li>
143	+	* </ul>
144	+	*
145	+	* <p>These bulk operations accept a {@code parallelismThreshold}
146	+	* argument. Methods proceed sequentially if the current map size is
147	+	* estimated to be less than the given threshold. Using a value of
148	+	* {@code Long.MAX_VALUE} suppresses all parallelism.  Using a value
149	+	* of {@code 1} results in maximal parallelism by partitioning into
150	+	* enough subtasks to fully utilize the {@link
151	+	* ForkJoinPool#commonPool()} that is used for all parallel
152	+	* computations. Normally, you would initially choose one of these
153	+	* extreme values, and then measure performance of using in-between
154	+	* values that trade off overhead versus throughput.
155	+	*
156	+	* <p>The concurrency properties of bulk operations follow
157	+	* from those of ConcurrentHashMapV8: Any non-null result returned
158	+	* from {@code get(key)} and related access methods bears a
159	+	* happens-before relation with the associated insertion or
160	+	* update.  The result of any bulk operation reflects the
161	+	* composition of these per-element relations (but is not
162	+	* necessarily atomic with respect to the map as a whole unless it
163	+	* is somehow known to be quiescent).  Conversely, because keys
164	+	* and values in the map are never null, null serves as a reliable
165	+	* atomic indicator of the current lack of any result.  To
166	+	* maintain this property, null serves as an implicit basis for
167	+	* all non-scalar reduction operations. For the double, long, and
168	+	* int versions, the basis should be one that, when combined with
169	+	* any other value, returns that other value (more formally, it
170	+	* should be the identity element for the reduction). Most common
171	+	* reductions have these properties; for example, computing a sum
172	+	* with basis 0 or a minimum with basis MAX_VALUE.
173	+	*
174	+	* <p>Search and transformation functions provided as arguments
175	+	* should similarly return null to indicate the lack of any result
176	+	* (in which case it is not used). In the case of mapped
177	+	* reductions, this also enables transformations to serve as
178	+	* filters, returning null (or, in the case of primitive
179	+	* specializations, the identity basis) if the element should not
180	+	* be combined. You can create compound transformations and
181	+	* filterings by composing them yourself under this "null means
182	+	* there is nothing there now" rule before using them in search or
183	+	* reduce operations.
184	+	*
185	+	* <p>Methods accepting and/or returning Entry arguments maintain
186	+	* key-value associations. They may be useful for example when
187	+	* finding the key for the greatest value. Note that "plain" Entry
188	+	* arguments can be supplied using {@code new
189	+	* AbstractMap.SimpleEntry(k,v)}.
190	+	*
191	+	* <p>Bulk operations may complete abruptly, throwing an
192	+	* exception encountered in the application of a supplied
193	+	* function. Bear in mind when handling such exceptions that other
194	+	* concurrently executing functions could also have thrown
195	+	* exceptions, or would have done so if the first exception had
196	+	* not occurred.
197	+	*
198	+	* <p>Speedups for parallel compared to sequential forms are common
199	+	* but not guaranteed.  Parallel operations involving brief functions
200	+	* on small maps may execute more slowly than sequential forms if the
201	+	* underlying work to parallelize the computation is more expensive
202	+	* than the computation itself.  Similarly, parallelization may not
203	+	* lead to much actual parallelism if all processors are busy
204	+	* performing unrelated tasks.
205	+	*
206	+	* <p>All arguments to all task methods must be non-null.
207	+	*
208	+	* <p><em>jsr166e note: During transition, this class
209	+	* uses nested functional interfaces with different names but the
210	+	* same forms as those expected for JDK8.</em>
211	+	*
212		* <p>This class is a member of the
213		* <a href="{@docRoot}/../technotes/guides/collections/index.html">
214		* Java Collections Framework</a>.
215		*
72	–	* <p><em>jsr166e note: This class is a candidate replacement for
73	–	* java.util.concurrent.ConcurrentHashMap.<em>
74	–	*
216		* @since 1.5
217		* @author Doug Lea
218		* @param <K> the type of keys maintained by this map
219		* @param <V> the type of mapped values
220		*/
221	<	public class ConcurrentHashMapV8<K, V>
222	<	implements ConcurrentMap<K, V>, Serializable {
221	>	public class ConcurrentHashMapV8<K,V>
222	>	implements ConcurrentMap<K,V>, Serializable {
223		private static final long serialVersionUID = 7249069246763182397L;
224
225		/**
226	<	* A function computing a mapping from the given key to a value,
227	<	* or {@code null} if there is no mapping. This is a place-holder
228	<	* for an upcoming JDK8 interface.
229	<	*/
230	<	public static interface MappingFunction<K, V> {
231	<	/**
232	<	* Returns a value for the given key, or null if there is no
233	<	* mapping. If this function throws an (unchecked) exception,
234	<	* the exception is rethrown to its caller, and no mapping is
235	<	* recorded.  Because this function is invoked within
95	<	* atomicity control, the computation should be short and
96	<	* simple. The most common usage is to construct a new object
97	<	* serving as an initial mapped value.
98	<	*
99	<	* @param key the (non-null) key
100	<	* @return a value, or null if none
226	>	* An object for traversing and partitioning elements of a source.
227	>	* This interface provides a subset of the functionality of JDK8
228	>	* java.util.Spliterator.
229	>	*/
230	>	public static interface ConcurrentHashMapSpliterator<T> {
231	>	/**
232	>	* If possible, returns a new spliterator covering
233	>	* approximately one half of the elements, which will not be
234	>	* covered by this spliterator. Returns null if cannot be
235	>	* split.
236		*/
237	<	V map(K key);
238	<	}
237	>	ConcurrentHashMapSpliterator<T> trySplit();
238	>	/**
239	>	* Returns an estimate of the number of elements covered by
240	>	* this Spliterator.
241	>	*/
242	>	long estimateSize();
243	>
244	>	/** Applies the action to each untraversed element */
245	>	void forEachRemaining(Action<? super T> action);
246	>	/** If an element remains, applies the action and returns true. */
247	>	boolean tryAdvance(Action<? super T> action);
248	>	}
249	>
250	>	// Sams
251	>	/** Interface describing a void action of one argument */
252	>	public interface Action<A> { void apply(A a); }
253	>	/** Interface describing a void action of two arguments */
254	>	public interface BiAction<A,B> { void apply(A a, B b); }
255	>	/** Interface describing a function of one argument */
256	>	public interface Fun<A,T> { T apply(A a); }
257	>	/** Interface describing a function of two arguments */
258	>	public interface BiFun<A,B,T> { T apply(A a, B b); }
259	>	/** Interface describing a function mapping its argument to a double */
260	>	public interface ObjectToDouble<A> { double apply(A a); }
261	>	/** Interface describing a function mapping its argument to a long */
262	>	public interface ObjectToLong<A> { long apply(A a); }
263	>	/** Interface describing a function mapping its argument to an int */
264	>	public interface ObjectToInt<A> {int apply(A a); }
265	>	/** Interface describing a function mapping two arguments to a double */
266	>	public interface ObjectByObjectToDouble<A,B> { double apply(A a, B b); }
267	>	/** Interface describing a function mapping two arguments to a long */
268	>	public interface ObjectByObjectToLong<A,B> { long apply(A a, B b); }
269	>	/** Interface describing a function mapping two arguments to an int */
270	>	public interface ObjectByObjectToInt<A,B> {int apply(A a, B b); }
271	>	/** Interface describing a function mapping two doubles to a double */
272	>	public interface DoubleByDoubleToDouble { double apply(double a, double b); }
273	>	/** Interface describing a function mapping two longs to a long */
274	>	public interface LongByLongToLong { long apply(long a, long b); }
275	>	/** Interface describing a function mapping two ints to an int */
276	>	public interface IntByIntToInt { int apply(int a, int b); }
277
278		/*
279		* Overview:
#	Line 108 | Line 281 | public class ConcurrentHashMapV8<K, V>
281		* The primary design goal of this hash table is to maintain
282		* concurrent readability (typically method get(), but also
283		* iterators and related methods) while minimizing update
284	<	* contention.
285	<	*
286	<	* Each key-value mapping is held in a Node.  Because Node fields
287	<	* can contain special values, they are defined using plain Object
288	<	* types. Similarly in turn, all internal methods that use them
289	<	* work off Object types. All public generic-typed methods relay
290	<	* in/out of these internal methods, supplying casts as needed.
284	>	* contention. Secondary goals are to keep space consumption about
285	>	* the same or better than java.util.HashMap, and to support high
286	>	* initial insertion rates on an empty table by many threads.
287	>	*
288	>	* This map usually acts as a binned (bucketed) hash table.  Each
289	>	* key-value mapping is held in a Node.  Most nodes are instances
290	>	* of the basic Node class with hash, key, value, and next
291	>	* fields. However, various subclasses exist: TreeNodes are
292	>	* arranged in balanced trees, not lists.  TreeBins hold the roots
293	>	* of sets of TreeNodes. ForwardingNodes are placed at the heads
294	>	* of bins during resizing. ReservationNodes are used as
295	>	* placeholders while establishing values in computeIfAbsent and
296	>	* related methods.  The types TreeBin, ForwardingNode, and
297	>	* ReservationNode do not hold normal user keys, values, or
298	>	* hashes, and are readily distinguishable during search etc
299	>	* because they have negative hash fields and null key and value
300	>	* fields. (These special nodes are either uncommon or transient,
301	>	* so the impact of carrying around some unused fields is
302	>	* insignificant.)
303		*
304		* The table is lazily initialized to a power-of-two size upon the
305	<	* first insertion.  Each bin in the table contains a (typically
306	<	* short) list of Nodes.  Table accesses require volatile/atomic
307	<	* reads, writes, and CASes.  Because there is no other way to
308	<	* arrange this without adding further indirections, we use
309	<	* intrinsics (sun.misc.Unsafe) operations.  The lists of nodes
310	<	* within bins are always accurately traversable under volatile
311	<	* reads, so long as lookups check hash code and non-nullness of
312	<	* key and value before checking key equality. (All valid hash
313	<	* codes are nonnegative. Negative values are reserved for special
314	<	* forwarding nodes; see below.)
315	<	*
316	<	* A bin may be locked during update (insert, delete, and replace)
317	<	* operations.  We do not want to waste the space required to
318	<	* associate a distinct lock object with each bin, so instead use
319	<	* the first node of a bin list itself as a lock, using builtin
320	<	* "synchronized" locks. These save space and we can live with
321	<	* only plain block-structured lock/unlock operations. Using the
322	<	* first node of a list as a lock does not by itself suffice
323	<	* though: When a node is locked, any update must first validate
324	<	* that it is still the first node, and retry if not. (Because new
325	<	* nodes are always appended to lists, once a node is first in a
326	<	* bin, it remains first until deleted or the bin becomes
327	<	* invalidated.)  However, update operations can and sometimes do
328	<	* still traverse the bin until the point of update, which helps
329	<	* reduce cache misses on retries.  This is a converse of sorts to
330	<	* the lazy locking technique described by Herlihy & Shavit. If
331	<	* there is no existing node during a put operation, then one can
332	<	* be CAS'ed in (without need for lock except in computeIfAbsent);
333	<	* the CAS serves as validation. This is on average the most
334	<	* common case for put operations -- under random hash codes, the
335	<	* distribution of nodes in bins follows a Poisson distribution
336	<	* (see http://en.wikipedia.org/wiki/Poisson_distribution) with a
337	<	* parameter of 0.5 on average under the default loadFactor of
338	<	* 0.75.  The expected number of locks covering different elements
339	<	* (i.e., bins with 2 or more nodes) is approximately 10% at
340	<	* steady state under default settings.  Lock contention
341	<	* probability for two threads accessing arbitrary distinct
342	<	* elements is, roughly, 1 / (8 * #elements).
343	<	*
344	<	* The table is resized when occupancy exceeds a threshold.  Only
345	<	* a single thread performs the resize (using field "resizing", to
346	<	* arrange exclusion), but the table otherwise remains usable for
347	<	* both reads and updates. Resizing proceeds by transferring bins,
348	<	* one by one, from the table to the next table.  Upon transfer,
349	<	* the old table bin contains only a special forwarding node (with
350	<	* negative hash code ("MOVED")) that contains the next table as
351	<	* its key. On encountering a forwarding node, access and update
352	<	* operations restart, using the new table. To ensure concurrent
353	<	* readability of traversals, transfers must proceed from the last
354	<	* bin (table.length - 1) up towards the first.  Any traversal
355	<	* starting from the first bin can then arrange to move to the new
356	<	* table for the rest of the traversal without revisiting nodes.
357	<	* This constrains bin transfers to a particular order, and so can
358	<	* block indefinitely waiting for the next lock, and other threads
359	<	* cannot help with the transfer. However, expected stalls are
360	<	* infrequent enough to not warrant the additional overhead and
361	<	* complexity of access and iteration schemes that could admit
362	<	* out-of-order or concurrent bin transfers.
363	<	*
364	<	* A similar traversal scheme (not yet implemented) can apply to
365	<	* partial traversals during partitioned aggregate operations.
366	<	* Also, read-only operations give up if ever forwarded to a null
367	<	* table, which provides support for shutdown-style clearing,
368	<	* which is also not currently implemented.
369	<	*
370	<	* The element count is maintained using a LongAdder, which avoids
371	<	* contention on updates but can encounter cache thrashing if read
372	<	* too frequently during concurrent updates. To avoid reading so
373	<	* often, resizing is normally attempted only upon adding to a bin
374	<	* already holding two or more nodes. Under the default threshold
375	<	* (0.75), and uniform hash distributions, the probability of this
376	<	* occurring at threshold is around 13%, meaning that only about 1
377	<	* in 8 puts check threshold (and after resizing, many fewer do
378	<	* so). But this approximation has high variance for small table
379	<	* sizes, so we check on any collision for sizes <= 64.  Further,
380	<	* to increase the probability that a resize occurs soon enough, we
381	<	* offset the threshold (see THRESHOLD_OFFSET) by the expected
382	<	* number of puts between checks. This is currently set to 8, in
383	<	* accord with the default load factor. In practice, this is
384	<	* rarely overridden, and in any case is close enough to other
385	<	* plausible values not to waste dynamic probability computation
386	<	* for more precision.
305	>	* first insertion.  Each bin in the table normally contains a
306	>	* list of Nodes (most often, the list has only zero or one Node).
307	>	* Table accesses require volatile/atomic reads, writes, and
308	>	* CASes.  Because there is no other way to arrange this without
309	>	* adding further indirections, we use intrinsics
310	>	* (sun.misc.Unsafe) operations.
311	>	*
312	>	* We use the top (sign) bit of Node hash fields for control
313	>	* purposes -- it is available anyway because of addressing
314	>	* constraints.  Nodes with negative hash fields are specially
315	>	* handled or ignored in map methods.
316	>	*
317	>	* Insertion (via put or its variants) of the first node in an
318	>	* empty bin is performed by just CASing it to the bin.  This is
319	>	* by far the most common case for put operations under most
320	>	* key/hash distributions.  Other update operations (insert,
321	>	* delete, and replace) require locks.  We do not want to waste
322	>	* the space required to associate a distinct lock object with
323	>	* each bin, so instead use the first node of a bin list itself as
324	>	* a lock. Locking support for these locks relies on builtin
325	>	* "synchronized" monitors.
326	>	*
327	>	* Using the first node of a list as a lock does not by itself
328	>	* suffice though: When a node is locked, any update must first
329	>	* validate that it is still the first node after locking it, and
330	>	* retry if not. Because new nodes are always appended to lists,
331	>	* once a node is first in a bin, it remains first until deleted
332	>	* or the bin becomes invalidated (upon resizing).
333	>	*
334	>	* The main disadvantage of per-bin locks is that other update
335	>	* operations on other nodes in a bin list protected by the same
336	>	* lock can stall, for example when user equals() or mapping
337	>	* functions take a long time.  However, statistically, under
338	>	* random hash codes, this is not a common problem.  Ideally, the
339	>	* frequency of nodes in bins follows a Poisson distribution
340	>	* (http://en.wikipedia.org/wiki/Poisson_distribution) with a
341	>	* parameter of about 0.5 on average, given the resizing threshold
342	>	* of 0.75, although with a large variance because of resizing
343	>	* granularity. Ignoring variance, the expected occurrences of
344	>	* list size k are (exp(-0.5) * pow(0.5, k) / factorial(k)). The
345	>	* first values are:
346	>	*
347	>	* 0:    0.60653066
348	>	* 1:    0.30326533
349	>	* 2:    0.07581633
350	>	* 3:    0.01263606
351	>	* 4:    0.00157952
352	>	* 5:    0.00015795
353	>	* 6:    0.00001316
354	>	* 7:    0.00000094
355	>	* 8:    0.00000006
356	>	* more: less than 1 in ten million
357	>	*
358	>	* Lock contention probability for two threads accessing distinct
359	>	* elements is roughly 1 / (8 * #elements) under random hashes.
360	>	*
361	>	* Actual hash code distributions encountered in practice
362	>	* sometimes deviate significantly from uniform randomness.  This
363	>	* includes the case when N > (1<<30), so some keys MUST collide.
364	>	* Similarly for dumb or hostile usages in which multiple keys are
365	>	* designed to have identical hash codes or ones that differs only
366	>	* in masked-out high bits. So we use a secondary strategy that
367	>	* applies when the number of nodes in a bin exceeds a
368	>	* threshold. These TreeBins use a balanced tree to hold nodes (a
369	>	* specialized form of red-black trees), bounding search time to
370	>	* O(log N).  Each search step in a TreeBin is at least twice as
371	>	* slow as in a regular list, but given that N cannot exceed
372	>	* (1<<64) (before running out of addresses) this bounds search
373	>	* steps, lock hold times, etc, to reasonable constants (roughly
374	>	* 100 nodes inspected per operation worst case) so long as keys
375	>	* are Comparable (which is very common -- String, Long, etc).
376	>	* TreeBin nodes (TreeNodes) also maintain the same "next"
377	>	* traversal pointers as regular nodes, so can be traversed in
378	>	* iterators in the same way.
379	>	*
380	>	* The table is resized when occupancy exceeds a percentage
381	>	* threshold (nominally, 0.75, but see below).  Any thread
382	>	* noticing an overfull bin may assist in resizing after the
383	>	* initiating thread allocates and sets up the replacement
384	>	* array. However, rather than stalling, these other threads may
385	>	* proceed with insertions etc.  The use of TreeBins shields us
386	>	* from the worst case effects of overfilling while resizes are in
387	>	* progress.  Resizing proceeds by transferring bins, one by one,
388	>	* from the table to the next table. To enable concurrency, the
389	>	* next table must be (incrementally) prefilled with place-holders
390	>	* serving as reverse forwarders to the old table.  Because we are
391	>	* using power-of-two expansion, the elements from each bin must
392	>	* either stay at same index, or move with a power of two
393	>	* offset. We eliminate unnecessary node creation by catching
394	>	* cases where old nodes can be reused because their next fields
395	>	* won't change.  On average, only about one-sixth of them need
396	>	* cloning when a table doubles. The nodes they replace will be
397	>	* garbage collectable as soon as they are no longer referenced by
398	>	* any reader thread that may be in the midst of concurrently
399	>	* traversing table.  Upon transfer, the old table bin contains
400	>	* only a special forwarding node (with hash field "MOVED") that
401	>	* contains the next table as its key. On encountering a
402	>	* forwarding node, access and update operations restart, using
403	>	* the new table.
404	>	*
405	>	* Each bin transfer requires its bin lock, which can stall
406	>	* waiting for locks while resizing. However, because other
407	>	* threads can join in and help resize rather than contend for
408	>	* locks, average aggregate waits become shorter as resizing
409	>	* progresses.  The transfer operation must also ensure that all
410	>	* accessible bins in both the old and new table are usable by any
411	>	* traversal.  This is arranged by proceeding from the last bin
412	>	* (table.length - 1) up towards the first.  Upon seeing a
413	>	* forwarding node, traversals (see class Traverser) arrange to
414	>	* move to the new table without revisiting nodes.  However, to
415	>	* ensure that no intervening nodes are skipped, bin splitting can
416	>	* only begin after the associated reverse-forwarders are in
417	>	* place.
418	>	*
419	>	* The traversal scheme also applies to partial traversals of
420	>	* ranges of bins (via an alternate Traverser constructor)
421	>	* to support partitioned aggregate operations.  Also, read-only
422	>	* operations give up if ever forwarded to a null table, which
423	>	* provides support for shutdown-style clearing, which is also not
424	>	* currently implemented.
425	>	*
426	>	* Lazy table initialization minimizes footprint until first use,
427	>	* and also avoids resizings when the first operation is from a
428	>	* putAll, constructor with map argument, or deserialization.
429	>	* These cases attempt to override the initial capacity settings,
430	>	* but harmlessly fail to take effect in cases of races.
431	>	*
432	>	* The element count is maintained using a specialization of
433	>	* LongAdder. We need to incorporate a specialization rather than
434	>	* just use a LongAdder in order to access implicit
435	>	* contention-sensing that leads to creation of multiple
436	>	* CounterCells.  The counter mechanics avoid contention on
437	>	* updates but can encounter cache thrashing if read too
438	>	* frequently during concurrent access. To avoid reading so often,
439	>	* resizing under contention is attempted only upon adding to a
440	>	* bin already holding two or more nodes. Under uniform hash
441	>	* distributions, the probability of this occurring at threshold
442	>	* is around 13%, meaning that only about 1 in 8 puts check
443	>	* threshold (and after resizing, many fewer do so).
444	>	*
445	>	* TreeBins use a special form of comparison for search and
446	>	* related operations (which is the main reason we cannot use
447	>	* existing collections such as TreeMaps). TreeBins contain
448	>	* Comparable elements, but may contain others, as well as
449	>	* elements that are Comparable but not necessarily Comparable
450	>	* for the same T, so we cannot invoke compareTo among them. To
451	>	* handle this, the tree is ordered primarily by hash value, then
452	>	* by Comparable.compareTo order if applicable.  On lookup at a
453	>	* node, if elements are not comparable or compare as 0 then both
454	>	* left and right children may need to be searched in the case of
455	>	* tied hash values. (This corresponds to the full list search
456	>	* that would be necessary if all elements were non-Comparable and
457	>	* had tied hashes.)  The red-black balancing code is updated from
458	>	* pre-jdk-collections
459	>	* (http://gee.cs.oswego.edu/dl/classes/collections/RBCell.java)
460	>	* based in turn on Cormen, Leiserson, and Rivest "Introduction to
461	>	* Algorithms" (CLR).
462	>	*
463	>	* TreeBins also require an additional locking mechanism.  While
464	>	* list traversal is always possible by readers even during
465	>	* updates, tree traversal is not, mainly because of tree-rotations
466	>	* that may change the root node and/or its linkages.  TreeBins
467	>	* include a simple read-write lock mechanism parasitic on the
468	>	* main bin-synchronization strategy: Structural adjustments
469	>	* associated with an insertion or removal are already bin-locked
470	>	* (and so cannot conflict with other writers) but must wait for
471	>	* ongoing readers to finish. Since there can be only one such
472	>	* waiter, we use a simple scheme using a single "waiter" field to
473	>	* block writers.  However, readers need never block.  If the root
474	>	* lock is held, they proceed along the slow traversal path (via
475	>	* next-pointers) until the lock becomes available or the list is
476	>	* exhausted, whichever comes first. These cases are not fast, but
477	>	* maximize aggregate expected throughput.
478	>	*
479	>	* Maintaining API and serialization compatibility with previous
480	>	* versions of this class introduces several oddities. Mainly: We
481	>	* leave untouched but unused constructor arguments refering to
482	>	* concurrencyLevel. We accept a loadFactor constructor argument,
483	>	* but apply it only to initial table capacity (which is the only
484	>	* time that we can guarantee to honor it.) We also declare an
485	>	* unused "Segment" class that is instantiated in minimal form
486	>	* only when serializing.
487	>	*
488	>	* This file is organized to make things a little easier to follow
489	>	* while reading than they might otherwise: First the main static
490	>	* declarations and utilities, then fields, then main public
491	>	* methods (with a few factorings of multiple public methods into
492	>	* internal ones), then sizing methods, trees, traversers, and
493	>	* bulk operations.
494		*/
495
496		/* ---------------- Constants -------------- */
497
498		/**
499	<	* The smallest allowed table capacity.  Must be a power of 2, at
500	<	* least 2.
499	>	* The largest possible table capacity.  This value must be
500	>	* exactly 1<<30 to stay within Java array allocation and indexing
501	>	* bounds for power of two table sizes, and is further required
502	>	* because the top two bits of 32bit hash fields are used for
503	>	* control purposes.
504		*/
505	<	static final int MINIMUM_CAPACITY = 2;
505	>	private static final int MAXIMUM_CAPACITY = 1 << 30;
506
507		/**
508	<	* The largest allowed table capacity.  Must be a power of 2, at
509	<	* most 1<<30.
508	>	* The default initial table capacity.  Must be a power of 2
509	>	* (i.e., at least 1) and at most MAXIMUM_CAPACITY.
510		*/
511	<	static final int MAXIMUM_CAPACITY = 1 << 30;
511	>	private static final int DEFAULT_CAPACITY = 16;
512
513		/**
514	<	* The default initial table capacity.  Must be a power of 2, at
515	<	* least MINIMUM_CAPACITY and at most MAXIMUM_CAPACITY.
514	>	* The largest possible (non-power of two) array size.
515	>	* Needed by toArray and related methods.
516		*/
517	<	static final int DEFAULT_CAPACITY = 16;
517	>	static final int MAX_ARRAY_SIZE = Integer.MAX_VALUE - 8;
518
519		/**
520	<	* The default load factor for this table, used when not otherwise
521	<	* specified in a constructor.
520	>	* The default concurrency level for this table. Unused but
521	>	* defined for compatibility with previous versions of this class.
522		*/
523	<	static final float DEFAULT_LOAD_FACTOR = 0.75f;
523	>	private static final int DEFAULT_CONCURRENCY_LEVEL = 16;
524
525		/**
526	<	* The default concurrency level for this table. Unused, but
527	<	* defined for compatibility with previous versions of this class.
526	>	* The load factor for this table. Overrides of this value in
527	>	* constructors affect only the initial table capacity.  The
528	>	* actual floating point value isn't normally used -- it is
529	>	* simpler to use expressions such as {@code n - (n >>> 2)} for
530	>	* the associated resizing threshold.
531		*/
532	<	static final int DEFAULT_CONCURRENCY_LEVEL = 16;
532	>	private static final float LOAD_FACTOR = 0.75f;
533
534		/**
535	<	* The count value to offset thresholds to compensate for checking
536	<	* for resizing only when inserting into bins with two or more
537	<	* elements. See above for explanation.
535	>	* The bin count threshold for using a tree rather than list for a
536	>	* bin.  Bins are converted to trees when adding an element to a
537	>	* bin with at least this many nodes. The value must be greater
538	>	* than 2, and should be at least 8 to mesh with assumptions in
539	>	* tree removal about conversion back to plain bins upon
540	>	* shrinkage.
541		*/
542	<	static final int THRESHOLD_OFFSET = 8;
542	>	static final int TREEIFY_THRESHOLD = 8;
543
544		/**
545	<	* Special node hash value indicating to use table in node.key
546	<	* Must be negative.
545	>	* The bin count threshold for untreeifying a (split) bin during a
546	>	* resize operation. Should be less than TREEIFY_THRESHOLD, and at
547	>	* most 6 to mesh with shrinkage detection under removal.
548		*/
549	<	static final int MOVED = -1;
248	<
249	<	/* ---------------- Fields -------------- */
549	>	static final int UNTREEIFY_THRESHOLD = 6;
550
551		/**
552	<	* The array of bins. Lazily initialized upon first insertion.
553	<	* Size is always a power of two. Accessed directly by inner
554	<	* classes.
552	>	* The smallest table capacity for which bins may be treeified.
553	>	* (Otherwise the table is resized if too many nodes in a bin.)
554	>	* The value should be at least 4 * TREEIFY_THRESHOLD to avoid
555	>	* conflicts between resizing and treeification thresholds.
556		*/
557	<	transient volatile Node[] table;
257	<
258	<	/** The counter maintaining number of elements. */
259	<	private transient final LongAdder counter;
260	<	/** Nonzero when table is being initialized or resized. Updated via CAS. */
261	<	private transient volatile int resizing;
262	<	/** The target load factor for the table. */
263	<	private transient float loadFactor;
264	<	/** The next element count value upon which to resize the table. */
265	<	private transient int threshold;
266	<	/** The initial capacity of the table. */
267	<	private transient int initCap;
268	<
269	<	// views
270	<	transient Set<K> keySet;
271	<	transient Set<Map.Entry<K,V>> entrySet;
272	<	transient Collection<V> values;
273	<
274	<	/** For serialization compatibility. Null unless serialized; see below */
275	<	Segment<K,V>[] segments;
557	>	static final int MIN_TREEIFY_CAPACITY = 64;
558
559		/**
560	<	* Applies a supplemental hash function to a given hashCode, which
561	<	* defends against poor quality hash functions.  The result must
562	<	* be non-negative, and for reasonable performance must have good
563	<	* avalanche properties; i.e., that each bit of the argument
564	<	* affects each bit (except sign bit) of the result.
560	>	* Minimum number of rebinnings per transfer step. Ranges are
561	>	* subdivided to allow multiple resizer threads.  This value
562	>	* serves as a lower bound to avoid resizers encountering
563	>	* excessive memory contention.  The value should be at least
564	>	* DEFAULT_CAPACITY.
565		*/
566	<	private static final int spread(int h) {
285	<	// Apply base step of MurmurHash; see http://code.google.com/p/smhasher/
286	<	h ^= h >>> 16;
287	<	h *= 0x85ebca6b;
288	<	h ^= h >>> 13;
289	<	h *= 0xc2b2ae35;
290	<	return (h >>> 16) ^ (h & 0x7fffffff); // mask out sign bit
291	<	}
566	>	private static final int MIN_TRANSFER_STRIDE = 16;
567
568	<	/**
569	<	* Key-value entry. Note that this is never exported out as a
570	<	* user-visible Map.Entry.
568	>	/*
569	>	* Encodings for Node hash fields. See above for explanation.
570	>	*/
571	>	static final int MOVED     = -1; // hash for forwarding nodes
572	>	static final int TREEBIN   = -2; // hash for roots of trees
573	>	static final int RESERVED  = -3; // hash for transient reservations
574	>	static final int HASH_BITS = 0x7fffffff; // usable bits of normal node hash
575	>
576	>	/** Number of CPUS, to place bounds on some sizings */
577	>	static final int NCPU = Runtime.getRuntime().availableProcessors();
578	>
579	>	/** For serialization compatibility. */
580	>	private static final ObjectStreamField[] serialPersistentFields = {
581	>	new ObjectStreamField("segments", Segment[].class),
582	>	new ObjectStreamField("segmentMask", Integer.TYPE),
583	>	new ObjectStreamField("segmentShift", Integer.TYPE)
584	>	};
585	>
586	>	/* ---------------- Nodes -------------- */
587	>
588	>	/**
589	>	* Key-value entry.  This class is never exported out as a
590	>	* user-mutable Map.Entry (i.e., one supporting setValue; see
591	>	* MapEntry below), but can be used for read-only traversals used
592	>	* in bulk tasks.  Subclasses of Node with a negative hash field
593	>	* are special, and contain null keys and values (but are never
594	>	* exported).  Otherwise, keys and vals are never null.
595		*/
596	<	static final class Node {
596	>	static class Node<K,V> implements Map.Entry<K,V> {
597		final int hash;
598	<	final Object key;
599	<	volatile Object val;
600	<	volatile Node next;
598	>	final K key;
599	>	volatile V val;
600	>	volatile Node<K,V> next;
601
602	<	Node(int hash, Object key, Object val, Node next) {
602	>	Node(int hash, K key, V val, Node<K,V> next) {
603		this.hash = hash;
604		this.key = key;
605		this.val = val;
606		this.next = next;
607		}
608	+
609	+	public final K getKey()       { return key; }
610	+	public final V getValue()     { return val; }
611	+	public final int hashCode()   { return key.hashCode() ^ val.hashCode(); }
612	+	public final String toString(){ return key + "=" + val; }
613	+	public final V setValue(V value) {
614	+	throw new UnsupportedOperationException();
615	+	}
616	+
617	+	public final boolean equals(Object o) {
618	+	Object k, v, u; Map.Entry<?,?> e;
619	+	return ((o instanceof Map.Entry) &&
620	+	(k = (e = (Map.Entry<?,?>)o).getKey()) != null &&
621	+	(v = e.getValue()) != null &&
622	+	(k == key || k.equals(key)) &&
623	+	(v == (u = val) || v.equals(u)));
624	+	}
625	+
626	+	/**
627	+	* Virtualized support for map.get(); overridden in subclasses.
628	+	*/
629	+	Node<K,V> find(int h, Object k) {
630	+	Node<K,V> e = this;
631	+	if (k != null) {
632	+	do {
633	+	K ek;
634	+	if (e.hash == h &&
635	+	((ek = e.key) == k || (ek != null && k.equals(ek))))
636	+	return e;
637	+	} while ((e = e.next) != null);
638	+	}
639	+	return null;
640	+	}
641		}
642
643	+	/* ---------------- Static utilities -------------- */
644	+
645	+	/**
646	+	* Spreads (XORs) higher bits of hash to lower and also forces top
647	+	* bit to 0. Because the table uses power-of-two masking, sets of
648	+	* hashes that vary only in bits above the current mask will
649	+	* always collide. (Among known examples are sets of Float keys
650	+	* holding consecutive whole numbers in small tables.)  So we
651	+	* apply a transform that spreads the impact of higher bits
652	+	* downward. There is a tradeoff between speed, utility, and
653	+	* quality of bit-spreading. Because many common sets of hashes
654	+	* are already reasonably distributed (so don't benefit from
655	+	* spreading), and because we use trees to handle large sets of
656	+	* collisions in bins, we just XOR some shifted bits in the
657	+	* cheapest possible way to reduce systematic lossage, as well as
658	+	* to incorporate impact of the highest bits that would otherwise
659	+	* never be used in index calculations because of table bounds.
660	+	*/
661	+	static final int spread(int h) {
662	+	return (h ^ (h >>> 16)) & HASH_BITS;
663	+	}
664	+
665	+	/**
666	+	* Returns a power of two table size for the given desired capacity.
667	+	* See Hackers Delight, sec 3.2
668	+	*/
669	+	private static final int tableSizeFor(int c) {
670	+	int n = c - 1;
671	+	n |= n >>> 1;
672	+	n |= n >>> 2;
673	+	n |= n >>> 4;
674	+	n |= n >>> 8;
675	+	n |= n >>> 16;
676	+	return (n < 0) ? 1 : (n >= MAXIMUM_CAPACITY) ? MAXIMUM_CAPACITY : n + 1;
677	+	}
678	+
679	+	/**
680	+	* Returns x's Class if it is of the form "class C implements
681	+	* Comparable<C>", else null.
682	+	*/
683	+	static Class<?> comparableClassFor(Object x) {
684	+	if (x instanceof Comparable) {
685	+	Class<?> c; Type[] ts, as; Type t; ParameterizedType p;
686	+	if ((c = x.getClass()) == String.class) // bypass checks
687	+	return c;
688	+	if ((ts = c.getGenericInterfaces()) != null) {
689	+	for (int i = 0; i < ts.length; ++i) {
690	+	if (((t = ts[i]) instanceof ParameterizedType) &&
691	+	((p = (ParameterizedType)t).getRawType() ==
692	+	Comparable.class) &&
693	+	(as = p.getActualTypeArguments()) != null &&
694	+	as.length == 1 && as[0] == c) // type arg is c
695	+	return c;
696	+	}
697	+	}
698	+	}
699	+	return null;
700	+	}
701	+
702	+	/**
703	+	* Returns k.compareTo(x) if x matches kc (k's screened comparable
704	+	* class), else 0.
705	+	*/
706	+	@SuppressWarnings({"rawtypes","unchecked"}) // for cast to Comparable
707	+	static int compareComparables(Class<?> kc, Object k, Object x) {
708	+	return (x == null || x.getClass() != kc ? 0 :
709	+	((Comparable)k).compareTo(x));
710	+	}
711	+
712	+	/* ---------------- Table element access -------------- */
713	+
714		/*
715		* Volatile access methods are used for table elements as well as
716	<	* elements of in-progress next table while resizing.  Uses in
717	<	* access and update methods are null checked by callers, and
718	<	* implicitly bounds-checked, relying on the invariants that tab
719	<	* arrays have non-zero size, and all indices are masked with
720	<	* (tab.length - 1) which is never negative and always less than
721	<	* length. The "relaxed" non-volatile forms are used only during
722	<	* table initialization. The only other usage is in
723	<	* HashIterator.advance, which performs explicit checks.
716	>	* elements of in-progress next table while resizing.  All uses of
717	>	* the tab arguments must be null checked by callers.  All callers
718	>	* also paranoically precheck that tab's length is not zero (or an
719	>	* equivalent check), thus ensuring that any index argument taking
720	>	* the form of a hash value anded with (length - 1) is a valid
721	>	* index.  Note that, to be correct wrt arbitrary concurrency
722	>	* errors by users, these checks must operate on local variables,
723	>	* which accounts for some odd-looking inline assignments below.
724	>	* Note that calls to setTabAt always occur within locked regions,
725	>	* and so in principle require only release ordering, not need
726	>	* full volatile semantics, but are currently coded as volatile
727	>	* writes to be conservative.
728	>	*/
729	>
730	>	@SuppressWarnings("unchecked")
731	>	static final <K,V> Node<K,V> tabAt(Node<K,V>[] tab, int i) {
732	>	return (Node<K,V>)U.getObjectVolatile(tab, ((long)i << ASHIFT) + ABASE);
733	>	}
734	>
735	>	static final <K,V> boolean casTabAt(Node<K,V>[] tab, int i,
736	>	Node<K,V> c, Node<K,V> v) {
737	>	return U.compareAndSwapObject(tab, ((long)i << ASHIFT) + ABASE, c, v);
738	>	}
739	>
740	>	static final <K,V> void setTabAt(Node<K,V>[] tab, int i, Node<K,V> v) {
741	>	U.putObjectVolatile(tab, ((long)i << ASHIFT) + ABASE, v);
742	>	}
743	>
744	>	/* ---------------- Fields -------------- */
745	>
746	>	/**
747	>	* The array of bins. Lazily initialized upon first insertion.
748	>	* Size is always a power of two. Accessed directly by iterators.
749	>	*/
750	>	transient volatile Node<K,V>[] table;
751	>
752	>	/**
753	>	* The next table to use; non-null only while resizing.
754	>	*/
755	>	private transient volatile Node<K,V>[] nextTable;
756	>
757	>	/**
758	>	* Base counter value, used mainly when there is no contention,
759	>	* but also as a fallback during table initialization
760	>	* races. Updated via CAS.
761		*/
762	+	private transient volatile long baseCount;
763
764	<	static final Node tabAt(Node[] tab, int i) { // used in HashIterator
765	<	return (Node)UNSAFE.getObjectVolatile(tab, ((long)i<<ASHIFT)+ABASE);
764	>	/**
765	>	* Table initialization and resizing control.  When negative, the
766	>	* table is being initialized or resized: -1 for initialization,
767	>	* else -(1 + the number of active resizing threads).  Otherwise,
768	>	* when table is null, holds the initial table size to use upon
769	>	* creation, or 0 for default. After initialization, holds the
770	>	* next element count value upon which to resize the table.
771	>	*/
772	>	private transient volatile int sizeCtl;
773	>
774	>	/**
775	>	* The next table index (plus one) to split while resizing.
776	>	*/
777	>	private transient volatile int transferIndex;
778	>
779	>	/**
780	>	* The least available table index to split while resizing.
781	>	*/
782	>	private transient volatile int transferOrigin;
783	>
784	>	/**
785	>	* Spinlock (locked via CAS) used when resizing and/or creating CounterCells.
786	>	*/
787	>	private transient volatile int cellsBusy;
788	>
789	>	/**
790	>	* Table of counter cells. When non-null, size is a power of 2.
791	>	*/
792	>	private transient volatile CounterCell[] counterCells;
793	>
794	>	// views
795	>	private transient KeySetView<K,V> keySet;
796	>	private transient ValuesView<K,V> values;
797	>	private transient EntrySetView<K,V> entrySet;
798	>
799	>
800	>	/* ---------------- Public operations -------------- */
801	>
802	>	/**
803	>	* Creates a new, empty map with the default initial table size (16).
804	>	*/
805	>	public ConcurrentHashMapV8() {
806		}
807
808	<	private static final boolean casTabAt(Node[] tab, int i, Node c, Node v) {
809	<	return UNSAFE.compareAndSwapObject(tab, ((long)i<<ASHIFT)+ABASE, c, v);
808	>	/**
809	>	* Creates a new, empty map with an initial table size
810	>	* accommodating the specified number of elements without the need
811	>	* to dynamically resize.
812	>	*
813	>	* @param initialCapacity The implementation performs internal
814	>	* sizing to accommodate this many elements.
815	>	* @throws IllegalArgumentException if the initial capacity of
816	>	* elements is negative
817	>	*/
818	>	public ConcurrentHashMapV8(int initialCapacity) {
819	>	if (initialCapacity < 0)
820	>	throw new IllegalArgumentException();
821	>	int cap = ((initialCapacity >= (MAXIMUM_CAPACITY >>> 1)) ?
822	>	MAXIMUM_CAPACITY :
823	>	tableSizeFor(initialCapacity + (initialCapacity >>> 1) + 1));
824	>	this.sizeCtl = cap;
825		}
826
827	<	private static final void setTabAt(Node[] tab, int i, Node v) {
828	<	UNSAFE.putObjectVolatile(tab, ((long)i<<ASHIFT)+ABASE, v);
827	>	/**
828	>	* Creates a new map with the same mappings as the given map.
829	>	*
830	>	* @param m the map
831	>	*/
832	>	public ConcurrentHashMapV8(Map<? extends K, ? extends V> m) {
833	>	this.sizeCtl = DEFAULT_CAPACITY;
834	>	putAll(m);
835	>	}
836	>
837	>	/**
838	>	* Creates a new, empty map with an initial table size based on
839	>	* the given number of elements ({@code initialCapacity}) and
840	>	* initial table density ({@code loadFactor}).
841	>	*
842	>	* @param initialCapacity the initial capacity. The implementation
843	>	* performs internal sizing to accommodate this many elements,
844	>	* given the specified load factor.
845	>	* @param loadFactor the load factor (table density) for
846	>	* establishing the initial table size
847	>	* @throws IllegalArgumentException if the initial capacity of
848	>	* elements is negative or the load factor is nonpositive
849	>	*
850	>	* @since 1.6
851	>	*/
852	>	public ConcurrentHashMapV8(int initialCapacity, float loadFactor) {
853	>	this(initialCapacity, loadFactor, 1);
854		}
855
856	<	private static final Node relaxedTabAt(Node[] tab, int i) {
857	<	return (Node)UNSAFE.getObject(tab, ((long)i<<ASHIFT)+ABASE);
856	>	/**
857	>	* Creates a new, empty map with an initial table size based on
858	>	* the given number of elements ({@code initialCapacity}), table
859	>	* density ({@code loadFactor}), and number of concurrently
860	>	* updating threads ({@code concurrencyLevel}).
861	>	*
862	>	* @param initialCapacity the initial capacity. The implementation
863	>	* performs internal sizing to accommodate this many elements,
864	>	* given the specified load factor.
865	>	* @param loadFactor the load factor (table density) for
866	>	* establishing the initial table size
867	>	* @param concurrencyLevel the estimated number of concurrently
868	>	* updating threads. The implementation may use this value as
869	>	* a sizing hint.
870	>	* @throws IllegalArgumentException if the initial capacity is
871	>	* negative or the load factor or concurrencyLevel are
872	>	* nonpositive
873	>	*/
874	>	public ConcurrentHashMapV8(int initialCapacity,
875	>	float loadFactor, int concurrencyLevel) {
876	>	if (!(loadFactor > 0.0f) || initialCapacity < 0 || concurrencyLevel <= 0)
877	>	throw new IllegalArgumentException();
878	>	if (initialCapacity < concurrencyLevel)   // Use at least as many bins
879	>	initialCapacity = concurrencyLevel;   // as estimated threads
880	>	long size = (long)(1.0 + (long)initialCapacity / loadFactor);
881	>	int cap = (size >= (long)MAXIMUM_CAPACITY) ?
882	>	MAXIMUM_CAPACITY : tableSizeFor((int)size);
883	>	this.sizeCtl = cap;
884		}
885
886	<	private static final void relaxedSetTabAt(Node[] tab, int i, Node v) {
887	<	UNSAFE.putObject(tab, ((long)i<<ASHIFT)+ABASE, v);
886	>	// Original (since JDK1.2) Map methods
887	>
888	>	/**
889	>	* {@inheritDoc}
890	>	*/
891	>	public int size() {
892	>	long n = sumCount();
893	>	return ((n < 0L) ? 0 :
894	>	(n > (long)Integer.MAX_VALUE) ? Integer.MAX_VALUE :
895	>	(int)n);
896		}
897
898	<	/* ---------------- Access and update operations -------------- */
898	>	/**
899	>	* {@inheritDoc}
900	>	*/
901	>	public boolean isEmpty() {
902	>	return sumCount() <= 0L; // ignore transient negative values
903	>	}
904
905	<	/** Implementation for get and containsKey */
906	<	private final Object internalGet(Object k) {
907	<	int h = spread(k.hashCode());
908	<	Node[] tab = table;
909	<	retry: while (tab != null) {
910	<	Node e = tabAt(tab, (tab.length - 1) & h);
911	<	while (e != null) {
912	<	int eh = e.hash;
913	<	if (eh == h) {
914	<	Object ek = e.key, ev = e.val;
915	<	if (ev != null && ek != null && (k == ek || k.equals(ek)))
916	<	return ev;
917	<	}
918	<	else if (eh < 0) { // bin was moved during resize
919	<	tab = (Node[])e.key;
920	<	continue retry;
921	<	}
922	<	e = e.next;
905	>	/**
906	>	* Returns the value to which the specified key is mapped,
907	>	* or {@code null} if this map contains no mapping for the key.
908	>	*
909	>	* <p>More formally, if this map contains a mapping from a key
910	>	* {@code k} to a value {@code v} such that {@code key.equals(k)},
911	>	* then this method returns {@code v}; otherwise it returns
912	>	* {@code null}.  (There can be at most one such mapping.)
913	>	*
914	>	* @throws NullPointerException if the specified key is null
915	>	*/
916	>	public V get(Object key) {
917	>	Node<K,V>[] tab; Node<K,V> e, p; int n, eh; K ek;
918	>	int h = spread(key.hashCode());
919	>	if ((tab = table) != null && (n = tab.length) > 0 &&
920	>	(e = tabAt(tab, (n - 1) & h)) != null) {
921	>	if ((eh = e.hash) == h) {
922	>	if ((ek = e.key) == key || (ek != null && key.equals(ek)))
923	>	return e.val;
924	>	}
925	>	else if (eh < 0)
926	>	return (p = e.find(h, key)) != null ? p.val : null;
927	>	while ((e = e.next) != null) {
928	>	if (e.hash == h &&
929	>	((ek = e.key) == key || (ek != null && key.equals(ek))))
930	>	return e.val;
931		}
364	–	break;
932		}
933		return null;
934		}
935
936	+	/**
937	+	* Tests if the specified object is a key in this table.
938	+	*
939	+	* @param  key possible key
940	+	* @return {@code true} if and only if the specified object
941	+	*         is a key in this table, as determined by the
942	+	*         {@code equals} method; {@code false} otherwise
943	+	* @throws NullPointerException if the specified key is null
944	+	*/
945	+	public boolean containsKey(Object key) {
946	+	return get(key) != null;
947	+	}
948	+
949	+	/**
950	+	* Returns {@code true} if this map maps one or more keys to the
951	+	* specified value. Note: This method may require a full traversal
952	+	* of the map, and is much slower than method {@code containsKey}.
953	+	*
954	+	* @param value value whose presence in this map is to be tested
955	+	* @return {@code true} if this map maps one or more keys to the
956	+	*         specified value
957	+	* @throws NullPointerException if the specified value is null
958	+	*/
959	+	public boolean containsValue(Object value) {
960	+	if (value == null)
961	+	throw new NullPointerException();
962	+	Node<K,V>[] t;
963	+	if ((t = table) != null) {
964	+	Traverser<K,V> it = new Traverser<K,V>(t, t.length, 0, t.length);
965	+	for (Node<K,V> p; (p = it.advance()) != null; ) {
966	+	V v;
967	+	if ((v = p.val) == value || (v != null && value.equals(v)))
968	+	return true;
969	+	}
970	+	}
971	+	return false;
972	+	}
973	+
974	+	/**
975	+	* Maps the specified key to the specified value in this table.
976	+	* Neither the key nor the value can be null.
977	+	*
978	+	* <p>The value can be retrieved by calling the {@code get} method
979	+	* with a key that is equal to the original key.
980	+	*
981	+	* @param key key with which the specified value is to be associated
982	+	* @param value value to be associated with the specified key
983	+	* @return the previous value associated with {@code key}, or
984	+	*         {@code null} if there was no mapping for {@code key}
985	+	* @throws NullPointerException if the specified key or value is null
986	+	*/
987	+	public V put(K key, V value) {
988	+	return putVal(key, value, false);
989	+	}
990
991		/** Implementation for put and putIfAbsent */
992	<	private final Object internalPut(Object k, Object v, boolean replace) {
993	<	int h = spread(k.hashCode());
994	<	Object oldVal = null;  // the previous value or null if none
995	<	Node[] tab = table;
996	<	for (;;) {
997	<	Node e; int i;
998	<	if (tab == null)
999	<	tab = grow(0);
1000	<	else if ((e = tabAt(tab, i = (tab.length - 1) & h)) == null) {
1001	<	if (casTabAt(tab, i, null, new Node(h, k, v, null)))
1002	<	break;
992	>	final V putVal(K key, V value, boolean onlyIfAbsent) {
993	>	if (key == null || value == null) throw new NullPointerException();
994	>	int hash = spread(key.hashCode());
995	>	int binCount = 0;
996	>	for (Node<K,V>[] tab = table;;) {
997	>	Node<K,V> f; int n, i, fh;
998	>	if (tab == null || (n = tab.length) == 0)
999	>	tab = initTable();
1000	>	else if ((f = tabAt(tab, i = (n - 1) & hash)) == null) {
1001	>	if (casTabAt(tab, i, null,
1002	>	new Node<K,V>(hash, key, value, null)))
1003	>	break;                   // no lock when adding to empty bin
1004		}
1005	<	else if (e.hash < 0)
1006	<	tab = (Node[])e.key;
1005	>	else if ((fh = f.hash) == MOVED)
1006	>	tab = helpTransfer(tab, f);
1007		else {
1008	<	boolean validated = false;
1009	<	boolean checkSize = false;
1010	<	synchronized (e) {
1011	<	if (tabAt(tab, i) == e) {
1012	<	validated = true;
1013	<	for (Node first = e;;) {
1014	<	Object ek, ev;
1015	<	if (e.hash == h &&
1016	<	(ek = e.key) != null &&
1017	<	(ev = e.val) != null &&
1018	<	(k == ek || k.equals(ek))) {
1019	<	oldVal = ev;
1020	<	if (replace)
1021	<	e.val = v;
1022	<	break;
1008	>	V oldVal = null;
1009	>	synchronized (f) {
1010	>	if (tabAt(tab, i) == f) {
1011	>	if (fh >= 0) {
1012	>	binCount = 1;
1013	>	for (Node<K,V> e = f;; ++binCount) {
1014	>	K ek;
1015	>	if (e.hash == hash &&
1016	>	((ek = e.key) == key ||
1017	>	(ek != null && key.equals(ek)))) {
1018	>	oldVal = e.val;
1019	>	if (!onlyIfAbsent)
1020	>	e.val = value;
1021	>	break;
1022	>	}
1023	>	Node<K,V> pred = e;
1024	>	if ((e = e.next) == null) {
1025	>	pred.next = new Node<K,V>(hash, key,
1026	>	value, null);
1027	>	break;
1028	>	}
1029		}
1030	<	Node last = e;
1031	<	if ((e = e.next) == null) {
1032	<	last.next = new Node(h, k, v, null);
1033	<	if (last != first || tab.length <= 64)
1034	<	checkSize = true;
1035	<	break;
1030	>	}
1031	>	else if (f instanceof TreeBin) {
1032	>	Node<K,V> p;
1033	>	binCount = 2;
1034	>	if ((p = ((TreeBin<K,V>)f).putTreeVal(hash, key,
1035	>	value)) != null) {
1036	>	oldVal = p.val;
1037	>	if (!onlyIfAbsent)
1038	>	p.val = value;
1039		}
1040		}
1041		}
1042		}
1043	<	if (validated) {
1044	<	if (checkSize && tab.length < MAXIMUM_CAPACITY &&
1045	<	resizing == 0 && counter.sum() >= threshold)
1046	<	grow(0);
1043	>	if (binCount != 0) {
1044	>	if (binCount >= TREEIFY_THRESHOLD)
1045	>	treeifyBin(tab, i);
1046	>	if (oldVal != null)
1047	>	return oldVal;
1048		break;
1049		}
1050		}
1051		}
1052	<	if (oldVal == null)
1053	<	counter.increment();
1054	<	return oldVal;
1052	>	addCount(1L, binCount);
1053	>	return null;
1054	>	}
1055	>
1056	>	/**
1057	>	* Copies all of the mappings from the specified map to this one.
1058	>	* These mappings replace any mappings that this map had for any of the
1059	>	* keys currently in the specified map.
1060	>	*
1061	>	* @param m mappings to be stored in this map
1062	>	*/
1063	>	public void putAll(Map<? extends K, ? extends V> m) {
1064	>	tryPresize(m.size());
1065	>	for (Map.Entry<? extends K, ? extends V> e : m.entrySet())
1066	>	putVal(e.getKey(), e.getValue(), false);
1067	>	}
1068	>
1069	>	/**
1070	>	* Removes the key (and its corresponding value) from this map.
1071	>	* This method does nothing if the key is not in the map.
1072	>	*
1073	>	* @param  key the key that needs to be removed
1074	>	* @return the previous value associated with {@code key}, or
1075	>	*         {@code null} if there was no mapping for {@code key}
1076	>	* @throws NullPointerException if the specified key is null
1077	>	*/
1078	>	public V remove(Object key) {
1079	>	return replaceNode(key, null, null);
1080		}
1081
1082		/**
#	Line 427 | Line 1084 | public class ConcurrentHashMapV8<K, V>
1084		* Replaces node value with v, conditional upon match of cv if
1085		* non-null.  If resulting value is null, delete.
1086		*/
1087	<	private final Object internalReplace(Object k, Object v, Object cv) {
1088	<	int h = spread(k.hashCode());
1089	<	Object oldVal = null;
1090	<	Node e; int i;
1091	<	Node[] tab = table;
1092	<	while (tab != null &&
1093	<	(e = tabAt(tab, i = (tab.length - 1) & h)) != null) {
1094	<	if (e.hash < 0)
1095	<	tab = (Node[])e.key;
1087	>	final V replaceNode(Object key, V value, Object cv) {
1088	>	int hash = spread(key.hashCode());
1089	>	for (Node<K,V>[] tab = table;;) {
1090	>	Node<K,V> f; int n, i, fh;
1091	>	if (tab == null || (n = tab.length) == 0 ||
1092	>	(f = tabAt(tab, i = (n - 1) & hash)) == null)
1093	>	break;
1094	>	else if ((fh = f.hash) == MOVED)
1095	>	tab = helpTransfer(tab, f);
1096		else {
1097	+	V oldVal = null;
1098		boolean validated = false;
1099	<	boolean deleted = false;
1100	<	synchronized (e) {
1101	<	if (tabAt(tab, i) == e) {
1102	<	validated = true;
1103	<	Node pred = null;
1104	<	do {
1105	<	Object ek, ev;
1106	<	if (e.hash == h &&
1107	<	(ek = e.key) != null &&
1108	<	(ev = e.val) != null &&
1109	<	(k == ek || k.equals(ek))) {
1110	<	if (cv == null || cv == ev || cv.equals(ev)) {
1111	<	oldVal = ev;
1112	<	if ((e.val = v) == null) {
1113	<	deleted = true;
1114	<	Node en = e.next;
1115	<	if (pred != null)
458	<	pred.next = en;
1099	>	synchronized (f) {
1100	>	if (tabAt(tab, i) == f) {
1101	>	if (fh >= 0) {
1102	>	validated = true;
1103	>	for (Node<K,V> e = f, pred = null;;) {
1104	>	K ek;
1105	>	if (e.hash == hash &&
1106	>	((ek = e.key) == key ||
1107	>	(ek != null && key.equals(ek)))) {
1108	>	V ev = e.val;
1109	>	if (cv == null || cv == ev ||
1110	>	(ev != null && cv.equals(ev))) {
1111	>	oldVal = ev;
1112	>	if (value != null)
1113	>	e.val = value;
1114	>	else if (pred != null)
1115	>	pred.next = e.next;
1116		else
1117	<	setTabAt(tab, i, en);
1117	>	setTabAt(tab, i, e.next);
1118		}
1119	+	break;
1120	+	}
1121	+	pred = e;
1122	+	if ((e = e.next) == null)
1123	+	break;
1124	+	}
1125	+	}
1126	+	else if (f instanceof TreeBin) {
1127	+	validated = true;
1128	+	TreeBin<K,V> t = (TreeBin<K,V>)f;
1129	+	TreeNode<K,V> r, p;
1130	+	if ((r = t.root) != null &&
1131	+	(p = r.findTreeNode(hash, key, null)) != null) {
1132	+	V pv = p.val;
1133	+	if (cv == null || cv == pv ||
1134	+	(pv != null && cv.equals(pv))) {
1135	+	oldVal = pv;
1136	+	if (value != null)
1137	+	p.val = value;
1138	+	else if (t.removeTreeNode(p))
1139	+	setTabAt(tab, i, untreeify(t.first));
1140		}
463	–	break;
1141		}
1142	<	pred = e;
466	<	} while ((e = e.next) != null);
1142	>	}
1143		}
1144		}
1145		if (validated) {
1146	<	if (deleted)
1147	<	counter.decrement();
1146	>	if (oldVal != null) {
1147	>	if (value == null)
1148	>	addCount(-1L, -1);
1149	>	return oldVal;
1150	>	}
1151		break;
1152		}
1153		}
1154		}
1155	<	return oldVal;
1155	>	return null;
1156		}
1157
1158	<	/** Implementation for computeIfAbsent and compute */
1159	<	@SuppressWarnings("unchecked")
1160	<	private final V internalCompute(K k,
1161	<	MappingFunction<? super K, ? extends V> f,
1162	<	boolean replace) {
1163	<	int h = spread(k.hashCode());
1164	<	V val = null;
1165	<	boolean added = false;
1166	<	Node[] tab = table;
1158	>	/**
1159	>	* Removes all of the mappings from this map.
1160	>	*/
1161	>	public void clear() {
1162	>	long delta = 0L; // negative number of deletions
1163	>	int i = 0;
1164	>	Node<K,V>[] tab = table;
1165	>	while (tab != null && i < tab.length) {
1166	>	int fh;
1167	>	Node<K,V> f = tabAt(tab, i);
1168	>	if (f == null)
1169	>	++i;
1170	>	else if ((fh = f.hash) == MOVED) {
1171	>	tab = helpTransfer(tab, f);
1172	>	i = 0; // restart
1173	>	}
1174	>	else {
1175	>	synchronized (f) {
1176	>	if (tabAt(tab, i) == f) {
1177	>	Node<K,V> p = (fh >= 0 ? f :
1178	>	(f instanceof TreeBin) ?
1179	>	((TreeBin<K,V>)f).first : null);
1180	>	while (p != null) {
1181	>	--delta;
1182	>	p = p.next;
1183	>	}
1184	>	setTabAt(tab, i++, null);
1185	>	}
1186	>	}
1187	>	}
1188	>	}
1189	>	if (delta != 0L)
1190	>	addCount(delta, -1);
1191	>	}
1192	>
1193	>	/**
1194	>	* Returns a {@link Set} view of the keys contained in this map.
1195	>	* The set is backed by the map, so changes to the map are
1196	>	* reflected in the set, and vice-versa. The set supports element
1197	>	* removal, which removes the corresponding mapping from this map,
1198	>	* via the {@code Iterator.remove}, {@code Set.remove},
1199	>	* {@code removeAll}, {@code retainAll}, and {@code clear}
1200	>	* operations.  It does not support the {@code add} or
1201	>	* {@code addAll} operations.
1202	>	*
1203	>	* <p>The view's {@code iterator} is a "weakly consistent" iterator
1204	>	* that will never throw {@link ConcurrentModificationException},
1205	>	* and guarantees to traverse elements as they existed upon
1206	>	* construction of the iterator, and may (but is not guaranteed to)
1207	>	* reflect any modifications subsequent to construction.
1208	>	*
1209	>	* @return the set view
1210	>	*/
1211	>	public KeySetView<K,V> keySet() {
1212	>	KeySetView<K,V> ks;
1213	>	return (ks = keySet) != null ? ks : (keySet = new KeySetView<K,V>(this, null));
1214	>	}
1215	>
1216	>	/**
1217	>	* Returns a {@link Collection} view of the values contained in this map.
1218	>	* The collection is backed by the map, so changes to the map are
1219	>	* reflected in the collection, and vice-versa.  The collection
1220	>	* supports element removal, which removes the corresponding
1221	>	* mapping from this map, via the {@code Iterator.remove},
1222	>	* {@code Collection.remove}, {@code removeAll},
1223	>	* {@code retainAll}, and {@code clear} operations.  It does not
1224	>	* support the {@code add} or {@code addAll} operations.
1225	>	*
1226	>	* <p>The view's {@code iterator} is a "weakly consistent" iterator
1227	>	* that will never throw {@link ConcurrentModificationException},
1228	>	* and guarantees to traverse elements as they existed upon
1229	>	* construction of the iterator, and may (but is not guaranteed to)
1230	>	* reflect any modifications subsequent to construction.
1231	>	*
1232	>	* @return the collection view
1233	>	*/
1234	>	public Collection<V> values() {
1235	>	ValuesView<K,V> vs;
1236	>	return (vs = values) != null ? vs : (values = new ValuesView<K,V>(this));
1237	>	}
1238	>
1239	>	/**
1240	>	* Returns a {@link Set} view of the mappings contained in this map.
1241	>	* The set is backed by the map, so changes to the map are
1242	>	* reflected in the set, and vice-versa.  The set supports element
1243	>	* removal, which removes the corresponding mapping from the map,
1244	>	* via the {@code Iterator.remove}, {@code Set.remove},
1245	>	* {@code removeAll}, {@code retainAll}, and {@code clear}
1246	>	* operations.
1247	>	*
1248	>	* <p>The view's {@code iterator} is a "weakly consistent" iterator
1249	>	* that will never throw {@link ConcurrentModificationException},
1250	>	* and guarantees to traverse elements as they existed upon
1251	>	* construction of the iterator, and may (but is not guaranteed to)
1252	>	* reflect any modifications subsequent to construction.
1253	>	*
1254	>	* @return the set view
1255	>	*/
1256	>	public Set<Map.Entry<K,V>> entrySet() {
1257	>	EntrySetView<K,V> es;
1258	>	return (es = entrySet) != null ? es : (entrySet = new EntrySetView<K,V>(this));
1259	>	}
1260	>
1261	>	/**
1262	>	* Returns the hash code value for this {@link Map}, i.e.,
1263	>	* the sum of, for each key-value pair in the map,
1264	>	* {@code key.hashCode() ^ value.hashCode()}.
1265	>	*
1266	>	* @return the hash code value for this map
1267	>	*/
1268	>	public int hashCode() {
1269	>	int h = 0;
1270	>	Node<K,V>[] t;
1271	>	if ((t = table) != null) {
1272	>	Traverser<K,V> it = new Traverser<K,V>(t, t.length, 0, t.length);
1273	>	for (Node<K,V> p; (p = it.advance()) != null; )
1274	>	h += p.key.hashCode() ^ p.val.hashCode();
1275	>	}
1276	>	return h;
1277	>	}
1278	>
1279	>	/**
1280	>	* Returns a string representation of this map.  The string
1281	>	* representation consists of a list of key-value mappings (in no
1282	>	* particular order) enclosed in braces ("{@code {}}").  Adjacent
1283	>	* mappings are separated by the characters {@code ", "} (comma
1284	>	* and space).  Each key-value mapping is rendered as the key
1285	>	* followed by an equals sign ("{@code =}") followed by the
1286	>	* associated value.
1287	>	*
1288	>	* @return a string representation of this map
1289	>	*/
1290	>	public String toString() {
1291	>	Node<K,V>[] t;
1292	>	int f = (t = table) == null ? 0 : t.length;
1293	>	Traverser<K,V> it = new Traverser<K,V>(t, f, 0, f);
1294	>	StringBuilder sb = new StringBuilder();
1295	>	sb.append('{');
1296	>	Node<K,V> p;
1297	>	if ((p = it.advance()) != null) {
1298	>	for (;;) {
1299	>	K k = p.key;
1300	>	V v = p.val;
1301	>	sb.append(k == this ? "(this Map)" : k);
1302	>	sb.append('=');
1303	>	sb.append(v == this ? "(this Map)" : v);
1304	>	if ((p = it.advance()) == null)
1305	>	break;
1306	>	sb.append(',').append(' ');
1307	>	}
1308	>	}
1309	>	return sb.append('}').toString();
1310	>	}
1311	>
1312	>	/**
1313	>	* Compares the specified object with this map for equality.
1314	>	* Returns {@code true} if the given object is a map with the same
1315	>	* mappings as this map.  This operation may return misleading
1316	>	* results if either map is concurrently modified during execution
1317	>	* of this method.
1318	>	*
1319	>	* @param o object to be compared for equality with this map
1320	>	* @return {@code true} if the specified object is equal to this map
1321	>	*/
1322	>	public boolean equals(Object o) {
1323	>	if (o != this) {
1324	>	if (!(o instanceof Map))
1325	>	return false;
1326	>	Map<?,?> m = (Map<?,?>) o;
1327	>	Node<K,V>[] t;
1328	>	int f = (t = table) == null ? 0 : t.length;
1329	>	Traverser<K,V> it = new Traverser<K,V>(t, f, 0, f);
1330	>	for (Node<K,V> p; (p = it.advance()) != null; ) {
1331	>	V val = p.val;
1332	>	Object v = m.get(p.key);
1333	>	if (v == null || (v != val && !v.equals(val)))
1334	>	return false;
1335	>	}
1336	>	for (Map.Entry<?,?> e : m.entrySet()) {
1337	>	Object mk, mv, v;
1338	>	if ((mk = e.getKey()) == null ||
1339	>	(mv = e.getValue()) == null ||
1340	>	(v = get(mk)) == null ||
1341	>	(mv != v && !mv.equals(v)))
1342	>	return false;
1343	>	}
1344	>	}
1345	>	return true;
1346	>	}
1347	>
1348	>	/**
1349	>	* Stripped-down version of helper class used in previous version,
1350	>	* declared for the sake of serialization compatibility
1351	>	*/
1352	>	static class Segment<K,V> extends ReentrantLock implements Serializable {
1353	>	private static final long serialVersionUID = 2249069246763182397L;
1354	>	final float loadFactor;
1355	>	Segment(float lf) { this.loadFactor = lf; }
1356	>	}
1357	>
1358	>	/**
1359	>	* Saves the state of the {@code ConcurrentHashMapV8} instance to a
1360	>	* stream (i.e., serializes it).
1361	>	* @param s the stream
1362	>	* @serialData
1363	>	* the key (Object) and value (Object)
1364	>	* for each key-value mapping, followed by a null pair.
1365	>	* The key-value mappings are emitted in no particular order.
1366	>	*/
1367	>	private void writeObject(java.io.ObjectOutputStream s)
1368	>	throws java.io.IOException {
1369	>	// For serialization compatibility
1370	>	// Emulate segment calculation from previous version of this class
1371	>	int sshift = 0;
1372	>	int ssize = 1;
1373	>	while (ssize < DEFAULT_CONCURRENCY_LEVEL) {
1374	>	++sshift;
1375	>	ssize <<= 1;
1376	>	}
1377	>	int segmentShift = 32 - sshift;
1378	>	int segmentMask = ssize - 1;
1379	>	@SuppressWarnings("unchecked") Segment<K,V>[] segments = (Segment<K,V>[])
1380	>	new Segment<?,?>[DEFAULT_CONCURRENCY_LEVEL];
1381	>	for (int i = 0; i < segments.length; ++i)
1382	>	segments[i] = new Segment<K,V>(LOAD_FACTOR);
1383	>	s.putFields().put("segments", segments);
1384	>	s.putFields().put("segmentShift", segmentShift);
1385	>	s.putFields().put("segmentMask", segmentMask);
1386	>	s.writeFields();
1387	>
1388	>	Node<K,V>[] t;
1389	>	if ((t = table) != null) {
1390	>	Traverser<K,V> it = new Traverser<K,V>(t, t.length, 0, t.length);
1391	>	for (Node<K,V> p; (p = it.advance()) != null; ) {
1392	>	s.writeObject(p.key);
1393	>	s.writeObject(p.val);
1394	>	}
1395	>	}
1396	>	s.writeObject(null);
1397	>	s.writeObject(null);
1398	>	segments = null; // throw away
1399	>	}
1400	>
1401	>	/**
1402	>	* Reconstitutes the instance from a stream (that is, deserializes it).
1403	>	* @param s the stream
1404	>	*/
1405	>	private void readObject(java.io.ObjectInputStream s)
1406	>	throws java.io.IOException, ClassNotFoundException {
1407	>	/*
1408	>	* To improve performance in typical cases, we create nodes
1409	>	* while reading, then place in table once size is known.
1410	>	* However, we must also validate uniqueness and deal with
1411	>	* overpopulated bins while doing so, which requires
1412	>	* specialized versions of putVal mechanics.
1413	>	*/
1414	>	sizeCtl = -1; // force exclusion for table construction
1415	>	s.defaultReadObject();
1416	>	long size = 0L;
1417	>	Node<K,V> p = null;
1418		for (;;) {
1419	<	Node e; int i;
1420	<	if (tab == null)
1421	<	tab = grow(0);
1422	<	else if ((e = tabAt(tab, i = (tab.length - 1) & h)) == null) {
1423	<	Node node = new Node(h, k, null, null);
1424	<	boolean validated = false;
1425	<	synchronized (node) {
1426	<	if (casTabAt(tab, i, null, node)) {
1427	<	validated = true;
1419	>	@SuppressWarnings("unchecked") K k = (K) s.readObject();
1420	>	@SuppressWarnings("unchecked") V v = (V) s.readObject();
1421	>	if (k != null && v != null) {
1422	>	p = new Node<K,V>(spread(k.hashCode()), k, v, p);
1423	>	++size;
1424	>	}
1425	>	else
1426	>	break;
1427	>	}
1428	>	if (size == 0L)
1429	>	sizeCtl = 0;
1430	>	else {
1431	>	int n;
1432	>	if (size >= (long)(MAXIMUM_CAPACITY >>> 1))
1433	>	n = MAXIMUM_CAPACITY;
1434	>	else {
1435	>	int sz = (int)size;
1436	>	n = tableSizeFor(sz + (sz >>> 1) + 1);
1437	>	}
1438	>	@SuppressWarnings({"rawtypes","unchecked"})
1439	>	Node<K,V>[] tab = (Node<K,V>[])new Node[n];
1440	>	int mask = n - 1;
1441	>	long added = 0L;
1442	>	while (p != null) {
1443	>	boolean insertAtFront;
1444	>	Node<K,V> next = p.next, first;
1445	>	int h = p.hash, j = h & mask;
1446	>	if ((first = tabAt(tab, j)) == null)
1447	>	insertAtFront = true;
1448	>	else {
1449	>	K k = p.key;
1450	>	if (first.hash < 0) {
1451	>	TreeBin<K,V> t = (TreeBin<K,V>)first;
1452	>	if (t.putTreeVal(h, k, p.val) == null)
1453	>	++added;
1454	>	insertAtFront = false;
1455	>	}
1456	>	else {
1457	>	int binCount = 0;
1458	>	insertAtFront = true;
1459	>	Node<K,V> q; K qk;
1460	>	for (q = first; q != null; q = q.next) {
1461	>	if (q.hash == h &&
1462	>	((qk = q.key) == k ||
1463	>	(qk != null && k.equals(qk)))) {
1464	>	insertAtFront = false;
1465	>	break;
1466	>	}
1467	>	++binCount;
1468	>	}
1469	>	if (insertAtFront && binCount >= TREEIFY_THRESHOLD) {
1470	>	insertAtFront = false;
1471	>	++added;
1472	>	p.next = first;
1473	>	TreeNode<K,V> hd = null, tl = null;
1474	>	for (q = p; q != null; q = q.next) {
1475	>	TreeNode<K,V> t = new TreeNode<K,V>
1476	>	(q.hash, q.key, q.val, null, null);
1477	>	if ((t.prev = tl) == null)
1478	>	hd = t;
1479	>	else
1480	>	tl.next = t;
1481	>	tl = t;
1482	>	}
1483	>	setTabAt(tab, j, new TreeBin<K,V>(hd));
1484	>	}
1485	>	}
1486	>	}
1487	>	if (insertAtFront) {
1488	>	++added;
1489	>	p.next = first;
1490	>	setTabAt(tab, j, p);
1491	>	}
1492	>	p = next;
1493	>	}
1494	>	table = tab;
1495	>	sizeCtl = n - (n >>> 2);
1496	>	baseCount = added;
1497	>	}
1498	>	}
1499	>
1500	>	// ConcurrentMap methods
1501	>
1502	>	/**
1503	>	* {@inheritDoc}
1504	>	*
1505	>	* @return the previous value associated with the specified key,
1506	>	*         or {@code null} if there was no mapping for the key
1507	>	* @throws NullPointerException if the specified key or value is null
1508	>	*/
1509	>	public V putIfAbsent(K key, V value) {
1510	>	return putVal(key, value, true);
1511	>	}
1512	>
1513	>	/**
1514	>	* {@inheritDoc}
1515	>	*
1516	>	* @throws NullPointerException if the specified key is null
1517	>	*/
1518	>	public boolean remove(Object key, Object value) {
1519	>	if (key == null)
1520	>	throw new NullPointerException();
1521	>	return value != null && replaceNode(key, null, value) != null;
1522	>	}
1523	>
1524	>	/**
1525	>	* {@inheritDoc}
1526	>	*
1527	>	* @throws NullPointerException if any of the arguments are null
1528	>	*/
1529	>	public boolean replace(K key, V oldValue, V newValue) {
1530	>	if (key == null || oldValue == null || newValue == null)
1531	>	throw new NullPointerException();
1532	>	return replaceNode(key, newValue, oldValue) != null;
1533	>	}
1534	>
1535	>	/**
1536	>	* {@inheritDoc}
1537	>	*
1538	>	* @return the previous value associated with the specified key,
1539	>	*         or {@code null} if there was no mapping for the key
1540	>	* @throws NullPointerException if the specified key or value is null
1541	>	*/
1542	>	public V replace(K key, V value) {
1543	>	if (key == null || value == null)
1544	>	throw new NullPointerException();
1545	>	return replaceNode(key, value, null);
1546	>	}
1547	>
1548	>	// Overrides of JDK8+ Map extension method defaults
1549	>
1550	>	/**
1551	>	* Returns the value to which the specified key is mapped, or the
1552	>	* given default value if this map contains no mapping for the
1553	>	* key.
1554	>	*
1555	>	* @param key the key whose associated value is to be returned
1556	>	* @param defaultValue the value to return if this map contains
1557	>	* no mapping for the given key
1558	>	* @return the mapping for the key, if present; else the default value
1559	>	* @throws NullPointerException if the specified key is null
1560	>	*/
1561	>	public V getOrDefault(Object key, V defaultValue) {
1562	>	V v;
1563	>	return (v = get(key)) == null ? defaultValue : v;
1564	>	}
1565	>
1566	>	public void forEach(BiAction<? super K, ? super V> action) {
1567	>	if (action == null) throw new NullPointerException();
1568	>	Node<K,V>[] t;
1569	>	if ((t = table) != null) {
1570	>	Traverser<K,V> it = new Traverser<K,V>(t, t.length, 0, t.length);
1571	>	for (Node<K,V> p; (p = it.advance()) != null; ) {
1572	>	action.apply(p.key, p.val);
1573	>	}
1574	>	}
1575	>	}
1576	>
1577	>	public void replaceAll(BiFun<? super K, ? super V, ? extends V> function) {
1578	>	if (function == null) throw new NullPointerException();
1579	>	Node<K,V>[] t;
1580	>	if ((t = table) != null) {
1581	>	Traverser<K,V> it = new Traverser<K,V>(t, t.length, 0, t.length);
1582	>	for (Node<K,V> p; (p = it.advance()) != null; ) {
1583	>	V oldValue = p.val;
1584	>	for (K key = p.key;;) {
1585	>	V newValue = function.apply(key, oldValue);
1586	>	if (newValue == null)
1587	>	throw new NullPointerException();
1588	>	if (replaceNode(key, newValue, oldValue) != null ||
1589	>	(oldValue = get(key)) == null)
1590	>	break;
1591	>	}
1592	>	}
1593	>	}
1594	>	}
1595	>
1596	>	/**
1597	>	* If the specified key is not already associated with a value,
1598	>	* attempts to compute its value using the given mapping function
1599	>	* and enters it into this map unless {@code null}.  The entire
1600	>	* method invocation is performed atomically, so the function is
1601	>	* applied at most once per key.  Some attempted update operations
1602	>	* on this map by other threads may be blocked while computation
1603	>	* is in progress, so the computation should be short and simple,
1604	>	* and must not attempt to update any other mappings of this map.
1605	>	*
1606	>	* @param key key with which the specified value is to be associated
1607	>	* @param mappingFunction the function to compute a value
1608	>	* @return the current (existing or computed) value associated with
1609	>	*         the specified key, or null if the computed value is null
1610	>	* @throws NullPointerException if the specified key or mappingFunction
1611	>	*         is null
1612	>	* @throws IllegalStateException if the computation detectably
1613	>	*         attempts a recursive update to this map that would
1614	>	*         otherwise never complete
1615	>	* @throws RuntimeException or Error if the mappingFunction does so,
1616	>	*         in which case the mapping is left unestablished
1617	>	*/
1618	>	public V computeIfAbsent(K key, Fun<? super K, ? extends V> mappingFunction) {
1619	>	if (key == null || mappingFunction == null)
1620	>	throw new NullPointerException();
1621	>	int h = spread(key.hashCode());
1622	>	V val = null;
1623	>	int binCount = 0;
1624	>	for (Node<K,V>[] tab = table;;) {
1625	>	Node<K,V> f; int n, i, fh;
1626	>	if (tab == null || (n = tab.length) == 0)
1627	>	tab = initTable();
1628	>	else if ((f = tabAt(tab, i = (n - 1) & h)) == null) {
1629	>	Node<K,V> r = new ReservationNode<K,V>();
1630	>	synchronized (r) {
1631	>	if (casTabAt(tab, i, null, r)) {
1632	>	binCount = 1;
1633	>	Node<K,V> node = null;
1634		try {
1635	<	val = f.map(k);
1636	<	if (val != null) {
1637	<	node.val = val;
1635	>	if ((val = mappingFunction.apply(key)) != null)
1636	>	node = new Node<K,V>(h, key, val, null);
1637	>	} finally {
1638	>	setTabAt(tab, i, node);
1639	>	}
1640	>	}
1641	>	}
1642	>	if (binCount != 0)
1643	>	break;
1644	>	}
1645	>	else if ((fh = f.hash) == MOVED)
1646	>	tab = helpTransfer(tab, f);
1647	>	else {
1648	>	boolean added = false;
1649	>	synchronized (f) {
1650	>	if (tabAt(tab, i) == f) {
1651	>	if (fh >= 0) {
1652	>	binCount = 1;
1653	>	for (Node<K,V> e = f;; ++binCount) {
1654	>	K ek; V ev;
1655	>	if (e.hash == h &&
1656	>	((ek = e.key) == key ||
1657	>	(ek != null && key.equals(ek)))) {
1658	>	val = e.val;
1659	>	break;
1660	>	}
1661	>	Node<K,V> pred = e;
1662	>	if ((e = e.next) == null) {
1663	>	if ((val = mappingFunction.apply(key)) != null) {
1664	>	added = true;
1665	>	pred.next = new Node<K,V>(h, key, val, null);
1666	>	}
1667	>	break;
1668	>	}
1669	>	}
1670	>	}
1671	>	else if (f instanceof TreeBin) {
1672	>	binCount = 2;
1673	>	TreeBin<K,V> t = (TreeBin<K,V>)f;
1674	>	TreeNode<K,V> r, p;
1675	>	if ((r = t.root) != null &&
1676	>	(p = r.findTreeNode(h, key, null)) != null)
1677	>	val = p.val;
1678	>	else if ((val = mappingFunction.apply(key)) != null) {
1679		added = true;
1680	+	t.putTreeVal(h, key, val);
1681	+	}
1682	+	}
1683	+	}
1684	+	}
1685	+	if (binCount != 0) {
1686	+	if (binCount >= TREEIFY_THRESHOLD)
1687	+	treeifyBin(tab, i);
1688	+	if (!added)
1689	+	return val;
1690	+	break;
1691	+	}
1692	+	}
1693	+	}
1694	+	if (val != null)
1695	+	addCount(1L, binCount);
1696	+	return val;
1697	+	}
1698	+
1699	+	/**
1700	+	* If the value for the specified key is present, attempts to
1701	+	* compute a new mapping given the key and its current mapped
1702	+	* value.  The entire method invocation is performed atomically.
1703	+	* Some attempted update operations on this map by other threads
1704	+	* may be blocked while computation is in progress, so the
1705	+	* computation should be short and simple, and must not attempt to
1706	+	* update any other mappings of this map.
1707	+	*
1708	+	* @param key key with which a value may be associated
1709	+	* @param remappingFunction the function to compute a value
1710	+	* @return the new value associated with the specified key, or null if none
1711	+	* @throws NullPointerException if the specified key or remappingFunction
1712	+	*         is null
1713	+	* @throws IllegalStateException if the computation detectably
1714	+	*         attempts a recursive update to this map that would
1715	+	*         otherwise never complete
1716	+	* @throws RuntimeException or Error if the remappingFunction does so,
1717	+	*         in which case the mapping is unchanged
1718	+	*/
1719	+	public V computeIfPresent(K key, BiFun<? super K, ? super V, ? extends V> remappingFunction) {
1720	+	if (key == null || remappingFunction == null)
1721	+	throw new NullPointerException();
1722	+	int h = spread(key.hashCode());
1723	+	V val = null;
1724	+	int delta = 0;
1725	+	int binCount = 0;
1726	+	for (Node<K,V>[] tab = table;;) {
1727	+	Node<K,V> f; int n, i, fh;
1728	+	if (tab == null || (n = tab.length) == 0)
1729	+	tab = initTable();
1730	+	else if ((f = tabAt(tab, i = (n - 1) & h)) == null)
1731	+	break;
1732	+	else if ((fh = f.hash) == MOVED)
1733	+	tab = helpTransfer(tab, f);
1734	+	else {
1735	+	synchronized (f) {
1736	+	if (tabAt(tab, i) == f) {
1737	+	if (fh >= 0) {
1738	+	binCount = 1;
1739	+	for (Node<K,V> e = f, pred = null;; ++binCount) {
1740	+	K ek;
1741	+	if (e.hash == h &&
1742	+	((ek = e.key) == key ||
1743	+	(ek != null && key.equals(ek)))) {
1744	+	val = remappingFunction.apply(key, e.val);
1745	+	if (val != null)
1746	+	e.val = val;
1747	+	else {
1748	+	delta = -1;
1749	+	Node<K,V> en = e.next;
1750	+	if (pred != null)
1751	+	pred.next = en;
1752	+	else
1753	+	setTabAt(tab, i, en);
1754	+	}
1755	+	break;
1756	+	}
1757	+	pred = e;
1758	+	if ((e = e.next) == null)
1759	+	break;
1760	+	}
1761	+	}
1762	+	else if (f instanceof TreeBin) {
1763	+	binCount = 2;
1764	+	TreeBin<K,V> t = (TreeBin<K,V>)f;
1765	+	TreeNode<K,V> r, p;
1766	+	if ((r = t.root) != null &&
1767	+	(p = r.findTreeNode(h, key, null)) != null) {
1768	+	val = remappingFunction.apply(key, p.val);
1769	+	if (val != null)
1770	+	p.val = val;
1771	+	else {
1772	+	delta = -1;
1773	+	if (t.removeTreeNode(p))
1774	+	setTabAt(tab, i, untreeify(t.first));
1775	+	}
1776	+	}
1777	+	}
1778	+	}
1779	+	}
1780	+	if (binCount != 0)
1781	+	break;
1782	+	}
1783	+	}
1784	+	if (delta != 0)
1785	+	addCount((long)delta, binCount);
1786	+	return val;
1787	+	}
1788	+
1789	+	/**
1790	+	* Attempts to compute a mapping for the specified key and its
1791	+	* current mapped value (or {@code null} if there is no current
1792	+	* mapping). The entire method invocation is performed atomically.
1793	+	* Some attempted update operations on this map by other threads
1794	+	* may be blocked while computation is in progress, so the
1795	+	* computation should be short and simple, and must not attempt to
1796	+	* update any other mappings of this Map.
1797	+	*
1798	+	* @param key key with which the specified value is to be associated
1799	+	* @param remappingFunction the function to compute a value
1800	+	* @return the new value associated with the specified key, or null if none
1801	+	* @throws NullPointerException if the specified key or remappingFunction
1802	+	*         is null
1803	+	* @throws IllegalStateException if the computation detectably
1804	+	*         attempts a recursive update to this map that would
1805	+	*         otherwise never complete
1806	+	* @throws RuntimeException or Error if the remappingFunction does so,
1807	+	*         in which case the mapping is unchanged
1808	+	*/
1809	+	public V compute(K key,
1810	+	BiFun<? super K, ? super V, ? extends V> remappingFunction) {
1811	+	if (key == null || remappingFunction == null)
1812	+	throw new NullPointerException();
1813	+	int h = spread(key.hashCode());
1814	+	V val = null;
1815	+	int delta = 0;
1816	+	int binCount = 0;
1817	+	for (Node<K,V>[] tab = table;;) {
1818	+	Node<K,V> f; int n, i, fh;
1819	+	if (tab == null || (n = tab.length) == 0)
1820	+	tab = initTable();
1821	+	else if ((f = tabAt(tab, i = (n - 1) & h)) == null) {
1822	+	Node<K,V> r = new ReservationNode<K,V>();
1823	+	synchronized (r) {
1824	+	if (casTabAt(tab, i, null, r)) {
1825	+	binCount = 1;
1826	+	Node<K,V> node = null;
1827	+	try {
1828	+	if ((val = remappingFunction.apply(key, null)) != null) {
1829	+	delta = 1;
1830	+	node = new Node<K,V>(h, key, val, null);
1831		}
1832		} finally {
1833	<	if (!added)
506	<	setTabAt(tab, i, null);
1833	>	setTabAt(tab, i, node);
1834		}
1835		}
1836		}
1837	<	if (validated)
1837	>	if (binCount != 0)
1838		break;
1839		}
1840	<	else if (e.hash < 0)
1841	<	tab = (Node[])e.key;
515	<	else if (Thread.holdsLock(e))
516	<	throw new IllegalStateException("Recursive map computation");
1840	>	else if ((fh = f.hash) == MOVED)
1841	>	tab = helpTransfer(tab, f);
1842		else {
1843	<	boolean validated = false;
1844	<	boolean checkSize = false;
1845	<	synchronized (e) {
1846	<	if (tabAt(tab, i) == e) {
1847	<	validated = true;
1848	<	for (Node first = e;;) {
1849	<	Object ek, ev, fv;
1850	<	if (e.hash == h &&
1851	<	(ek = e.key) != null &&
1852	<	(ev = e.val) != null &&
1853	<	(k == ek || k.equals(ek))) {
1854	<	if (replace && (fv = f.map(k)) != null)
1855	<	ev = e.val = fv;
1856	<	val = (V)ev;
1857	<	break;
1843	>	synchronized (f) {
1844	>	if (tabAt(tab, i) == f) {
1845	>	if (fh >= 0) {
1846	>	binCount = 1;
1847	>	for (Node<K,V> e = f, pred = null;; ++binCount) {
1848	>	K ek;
1849	>	if (e.hash == h &&
1850	>	((ek = e.key) == key ||
1851	>	(ek != null && key.equals(ek)))) {
1852	>	val = remappingFunction.apply(key, e.val);
1853	>	if (val != null)
1854	>	e.val = val;
1855	>	else {
1856	>	delta = -1;
1857	>	Node<K,V> en = e.next;
1858	>	if (pred != null)
1859	>	pred.next = en;
1860	>	else
1861	>	setTabAt(tab, i, en);
1862	>	}
1863	>	break;
1864	>	}
1865	>	pred = e;
1866	>	if ((e = e.next) == null) {
1867	>	val = remappingFunction.apply(key, null);
1868	>	if (val != null) {
1869	>	delta = 1;
1870	>	pred.next =
1871	>	new Node<K,V>(h, key, val, null);
1872	>	}
1873	>	break;
1874	>	}
1875		}
1876	<	Node last = e;
1877	<	if ((e = e.next) == null) {
1878	<	if ((val = f.map(k)) != null) {
1879	<	last.next = new Node(h, k, val, null);
1880	<	added = true;
1881	<	if (last != first || tab.length <= 64)
1882	<	checkSize = true;
1876	>	}
1877	>	else if (f instanceof TreeBin) {
1878	>	binCount = 1;
1879	>	TreeBin<K,V> t = (TreeBin<K,V>)f;
1880	>	TreeNode<K,V> r, p;
1881	>	if ((r = t.root) != null)
1882	>	p = r.findTreeNode(h, key, null);
1883	>	else
1884	>	p = null;
1885	>	V pv = (p == null) ? null : p.val;
1886	>	val = remappingFunction.apply(key, pv);
1887	>	if (val != null) {
1888	>	if (p != null)
1889	>	p.val = val;
1890	>	else {
1891	>	delta = 1;
1892	>	t.putTreeVal(h, key, val);
1893		}
1894	<	break;
1894	>	}
1895	>	else if (p != null) {
1896	>	delta = -1;
1897	>	if (t.removeTreeNode(p))
1898	>	setTabAt(tab, i, untreeify(t.first));
1899		}
1900		}
1901		}
1902		}
1903	<	if (validated) {
1904	<	if (checkSize && tab.length < MAXIMUM_CAPACITY &&
1905	<	resizing == 0 && counter.sum() >= threshold)
550	<	grow(0);
1903	>	if (binCount != 0) {
1904	>	if (binCount >= TREEIFY_THRESHOLD)
1905	>	treeifyBin(tab, i);
1906		break;
1907		}
1908		}
1909		}
1910	<	if (added)
1911	<	counter.increment();
1910	>	if (delta != 0)
1911	>	addCount((long)delta, binCount);
1912		return val;
1913		}
1914
1915	<	/*
1916	<	* Reclassifies nodes in each bin to new table.  Because we are
1917	<	* using power-of-two expansion, the elements from each bin must
1918	<	* either stay at same index, or move with a power of two
1919	<	* offset. We eliminate unnecessary node creation by catching
1920	<	* cases where old nodes can be reused because their next fields
1921	<	* won't change.  Statistically, at the default threshold, only
1922	<	* about one-sixth of them need cloning when a table doubles. The
1923	<	* nodes they replace will be garbage collectable as soon as they
1924	<	* are no longer referenced by any reader thread that may be in
1925	<	* the midst of concurrently traversing table.
1926	<	*
1927	<	* Transfers are done from the bottom up to preserve iterator
1928	<	* traversability. On each step, the old bin is locked,
1929	<	* moved/copied, and then replaced with a forwarding node.
1930	<	*/
1931	<	private static final void transfer(Node[] tab, Node[] nextTab) {
1932	<	int n = tab.length;
1933	<	int mask = nextTab.length - 1;
1934	<	Node fwd = new Node(MOVED, nextTab, null, null);
1935	<	for (int i = n - 1; i >= 0; --i) {
1936	<	for (Node e;;) {
1937	<	if ((e = tabAt(tab, i)) == null) {
1938	<	if (casTabAt(tab, i, e, fwd))
1939	<	break;
1915	>	/**
1916	>	* If the specified key is not already associated with a
1917	>	* (non-null) value, associates it with the given value.
1918	>	* Otherwise, replaces the value with the results of the given
1919	>	* remapping function, or removes if {@code null}. The entire
1920	>	* method invocation is performed atomically.  Some attempted
1921	>	* update operations on this map by other threads may be blocked
1922	>	* while computation is in progress, so the computation should be
1923	>	* short and simple, and must not attempt to update any other
1924	>	* mappings of this Map.
1925	>	*
1926	>	* @param key key with which the specified value is to be associated
1927	>	* @param value the value to use if absent
1928	>	* @param remappingFunction the function to recompute a value if present
1929	>	* @return the new value associated with the specified key, or null if none
1930	>	* @throws NullPointerException if the specified key or the
1931	>	*         remappingFunction is null
1932	>	* @throws RuntimeException or Error if the remappingFunction does so,
1933	>	*         in which case the mapping is unchanged
1934	>	*/
1935	>	public V merge(K key, V value, BiFun<? super V, ? super V, ? extends V> remappingFunction) {
1936	>	if (key == null || value == null || remappingFunction == null)
1937	>	throw new NullPointerException();
1938	>	int h = spread(key.hashCode());
1939	>	V val = null;
1940	>	int delta = 0;
1941	>	int binCount = 0;
1942	>	for (Node<K,V>[] tab = table;;) {
1943	>	Node<K,V> f; int n, i, fh;
1944	>	if (tab == null || (n = tab.length) == 0)
1945	>	tab = initTable();
1946	>	else if ((f = tabAt(tab, i = (n - 1) & h)) == null) {
1947	>	if (casTabAt(tab, i, null, new Node<K,V>(h, key, value, null))) {
1948	>	delta = 1;
1949	>	val = value;
1950	>	break;
1951		}
1952	<	else {
1953	<	int idx = e.hash & mask;
1954	<	boolean validated = false;
1955	<	synchronized (e) {
1956	<	if (tabAt(tab, i) == e) {
1957	<	validated = true;
1958	<	Node lastRun = e;
1959	<	for (Node p = e.next; p != null; p = p.next) {
1960	<	int j = p.hash & mask;
1961	<	if (j != idx) {
1962	<	idx = j;
1963	<	lastRun = p;
1952	>	}
1953	>	else if ((fh = f.hash) == MOVED)
1954	>	tab = helpTransfer(tab, f);
1955	>	else {
1956	>	synchronized (f) {
1957	>	if (tabAt(tab, i) == f) {
1958	>	if (fh >= 0) {
1959	>	binCount = 1;
1960	>	for (Node<K,V> e = f, pred = null;; ++binCount) {
1961	>	K ek;
1962	>	if (e.hash == h &&
1963	>	((ek = e.key) == key ||
1964	>	(ek != null && key.equals(ek)))) {
1965	>	val = remappingFunction.apply(e.val, value);
1966	>	if (val != null)
1967	>	e.val = val;
1968	>	else {
1969	>	delta = -1;
1970	>	Node<K,V> en = e.next;
1971	>	if (pred != null)
1972	>	pred.next = en;
1973	>	else
1974	>	setTabAt(tab, i, en);
1975	>	}
1976	>	break;
1977	>	}
1978	>	pred = e;
1979	>	if ((e = e.next) == null) {
1980	>	delta = 1;
1981	>	val = value;
1982	>	pred.next =
1983	>	new Node<K,V>(h, key, val, null);
1984	>	break;
1985		}
1986		}
1987	<	relaxedSetTabAt(nextTab, idx, lastRun);
1988	<	for (Node p = e; p != lastRun; p = p.next) {
1989	<	int h = p.hash;
1990	<	int j = h & mask;
1991	<	Node r = relaxedTabAt(nextTab, j);
1992	<	relaxedSetTabAt(nextTab, j,
1993	<	new Node(h, p.key, p.val, r));
1987	>	}
1988	>	else if (f instanceof TreeBin) {
1989	>	binCount = 2;
1990	>	TreeBin<K,V> t = (TreeBin<K,V>)f;
1991	>	TreeNode<K,V> r = t.root;
1992	>	TreeNode<K,V> p = (r == null) ? null :
1993	>	r.findTreeNode(h, key, null);
1994	>	val = (p == null) ? value :
1995	>	remappingFunction.apply(p.val, value);
1996	>	if (val != null) {
1997	>	if (p != null)
1998	>	p.val = val;
1999	>	else {
2000	>	delta = 1;
2001	>	t.putTreeVal(h, key, val);
2002	>	}
2003	>	}
2004	>	else if (p != null) {
2005	>	delta = -1;
2006	>	if (t.removeTreeNode(p))
2007	>	setTabAt(tab, i, untreeify(t.first));
2008		}
608	–	setTabAt(tab, i, fwd);
2009		}
2010		}
2011	<	if (validated)
2012	<	break;
2011	>	}
2012	>	if (binCount != 0) {
2013	>	if (binCount >= TREEIFY_THRESHOLD)
2014	>	treeifyBin(tab, i);
2015	>	break;
2016		}
2017		}
2018		}
2019	+	if (delta != 0)
2020	+	addCount((long)delta, binCount);
2021	+	return val;
2022		}
2023
2024	+	// Hashtable legacy methods
2025	+
2026		/**
2027	<	* If not already resizing, initializes or creates next table and
2028	<	* transfers bins. Rechecks occupancy after a transfer to see if
2029	<	* another resize is already needed because resizings are lagging
2030	<	* additions.
2031	<	*
2032	<	* @param sizeHint overridden capacity target (nonzero only from putAll)
2033	<	* @return current table
2034	<	*/
2035	<	private final Node[] grow(int sizeHint) {
2036	<	if (resizing == 0 &&
2037	<	UNSAFE.compareAndSwapInt(this, resizingOffset, 0, 1)) {
2038	<	try {
2027	>	* Legacy method testing if some key maps into the specified value
2028	>	* in this table.  This method is identical in functionality to
2029	>	* {@link #containsValue(Object)}, and exists solely to ensure
2030	>	* full compatibility with class {@link java.util.Hashtable},
2031	>	* which supported this method prior to introduction of the
2032	>	* Java Collections framework.
2033	>	*
2034	>	* @param  value a value to search for
2035	>	* @return {@code true} if and only if some key maps to the
2036	>	*         {@code value} argument in this table as
2037	>	*         determined by the {@code equals} method;
2038	>	*         {@code false} otherwise
2039	>	* @throws NullPointerException if the specified value is null
2040	>	*/
2041	>	@Deprecated public boolean contains(Object value) {
2042	>	return containsValue(value);
2043	>	}
2044	>
2045	>	/**
2046	>	* Returns an enumeration of the keys in this table.
2047	>	*
2048	>	* @return an enumeration of the keys in this table
2049	>	* @see #keySet()
2050	>	*/
2051	>	public Enumeration<K> keys() {
2052	>	Node<K,V>[] t;
2053	>	int f = (t = table) == null ? 0 : t.length;
2054	>	return new KeyIterator<K,V>(t, f, 0, f, this);
2055	>	}
2056	>
2057	>	/**
2058	>	* Returns an enumeration of the values in this table.
2059	>	*
2060	>	* @return an enumeration of the values in this table
2061	>	* @see #values()
2062	>	*/
2063	>	public Enumeration<V> elements() {
2064	>	Node<K,V>[] t;
2065	>	int f = (t = table) == null ? 0 : t.length;
2066	>	return new ValueIterator<K,V>(t, f, 0, f, this);
2067	>	}
2068	>
2069	>	// ConcurrentHashMapV8-only methods
2070	>
2071	>	/**
2072	>	* Returns the number of mappings. This method should be used
2073	>	* instead of {@link #size} because a ConcurrentHashMapV8 may
2074	>	* contain more mappings than can be represented as an int. The
2075	>	* value returned is an estimate; the actual count may differ if
2076	>	* there are concurrent insertions or removals.
2077	>	*
2078	>	* @return the number of mappings
2079	>	* @since 1.8
2080	>	*/
2081	>	public long mappingCount() {
2082	>	long n = sumCount();
2083	>	return (n < 0L) ? 0L : n; // ignore transient negative values
2084	>	}
2085	>
2086	>	/**
2087	>	* Creates a new {@link Set} backed by a ConcurrentHashMapV8
2088	>	* from the given type to {@code Boolean.TRUE}.
2089	>	*
2090	>	* @return the new set
2091	>	* @since 1.8
2092	>	*/
2093	>	public static <K> KeySetView<K,Boolean> newKeySet() {
2094	>	return new KeySetView<K,Boolean>
2095	>	(new ConcurrentHashMapV8<K,Boolean>(), Boolean.TRUE);
2096	>	}
2097	>
2098	>	/**
2099	>	* Creates a new {@link Set} backed by a ConcurrentHashMapV8
2100	>	* from the given type to {@code Boolean.TRUE}.
2101	>	*
2102	>	* @param initialCapacity The implementation performs internal
2103	>	* sizing to accommodate this many elements.
2104	>	* @return the new set
2105	>	* @throws IllegalArgumentException if the initial capacity of
2106	>	* elements is negative
2107	>	* @since 1.8
2108	>	*/
2109	>	public static <K> KeySetView<K,Boolean> newKeySet(int initialCapacity) {
2110	>	return new KeySetView<K,Boolean>
2111	>	(new ConcurrentHashMapV8<K,Boolean>(initialCapacity), Boolean.TRUE);
2112	>	}
2113	>
2114	>	/**
2115	>	* Returns a {@link Set} view of the keys in this map, using the
2116	>	* given common mapped value for any additions (i.e., {@link
2117	>	* Collection#add} and {@link Collection#addAll(Collection)}).
2118	>	* This is of course only appropriate if it is acceptable to use
2119	>	* the same value for all additions from this view.
2120	>	*
2121	>	* @param mappedValue the mapped value to use for any additions
2122	>	* @return the set view
2123	>	* @throws NullPointerException if the mappedValue is null
2124	>	*/
2125	>	public KeySetView<K,V> keySet(V mappedValue) {
2126	>	if (mappedValue == null)
2127	>	throw new NullPointerException();
2128	>	return new KeySetView<K,V>(this, mappedValue);
2129	>	}
2130	>
2131	>	/* ---------------- Special Nodes -------------- */
2132	>
2133	>	/**
2134	>	* A node inserted at head of bins during transfer operations.
2135	>	*/
2136	>	static final class ForwardingNode<K,V> extends Node<K,V> {
2137	>	final Node<K,V>[] nextTable;
2138	>	ForwardingNode(Node<K,V>[] tab) {
2139	>	super(MOVED, null, null, null);
2140	>	this.nextTable = tab;
2141	>	}
2142	>
2143	>	Node<K,V> find(int h, Object k) {
2144	>	// loop to avoid arbitrarily deep recursion on forwarding nodes
2145	>	outer: for (Node<K,V>[] tab = nextTable;;) {
2146	>	Node<K,V> e; int n;
2147	>	if (k == null || tab == null || (n = tab.length) == 0 ||
2148	>	(e = tabAt(tab, (n - 1) & h)) == null)
2149	>	return null;
2150		for (;;) {
2151	<	int cap, n;
2152	<	Node[] tab = table;
2153	<	if (tab == null) {
2154	<	int c = initCap;
2155	<	if (c < sizeHint)
2156	<	c = sizeHint;
2157	<	if (c == DEFAULT_CAPACITY)
2158	<	cap = c;
640	<	else if (c >= MAXIMUM_CAPACITY)
641	<	cap = MAXIMUM_CAPACITY;
642	<	else {
643	<	cap = MINIMUM_CAPACITY;
644	<	while (cap < c)
645	<	cap <<= 1;
2151	>	int eh; K ek;
2152	>	if ((eh = e.hash) == h &&
2153	>	((ek = e.key) == k || (ek != null && k.equals(ek))))
2154	>	return e;
2155	>	if (eh < 0) {
2156	>	if (e instanceof ForwardingNode) {
2157	>	tab = ((ForwardingNode<K,V>)e).nextTable;
2158	>	continue outer;
2159		}
2160	+	else
2161	+	return e.find(h, k);
2162		}
2163	<	else if ((n = tab.length) < MAXIMUM_CAPACITY &&
2164	<	(sizeHint <= 0 || n < sizeHint))
2165	<	cap = n << 1;
2166	<	else
2167	<	break;
2168	<	threshold = (int)(cap * loadFactor) - THRESHOLD_OFFSET;
2169	<	Node[] nextTab = new Node[cap];
2170	<	if (tab != null)
2171	<	transfer(tab, nextTab);
2172	<	table = nextTab;
2173	<	if (tab == null || cap >= MAXIMUM_CAPACITY ||
2174	<	((sizeHint > 0) ? cap >= sizeHint :
2175	<	counter.sum() < threshold))
2163	>	if ((e = e.next) == null)
2164	>	return null;
2165	>	}
2166	>	}
2167	>	}
2168	>	}
2169	>
2170	>	/**
2171	>	* A place-holder node used in computeIfAbsent and compute
2172	>	*/
2173	>	static final class ReservationNode<K,V> extends Node<K,V> {
2174	>	ReservationNode() {
2175	>	super(RESERVED, null, null, null);
2176	>	}
2177	>
2178	>	Node<K,V> find(int h, Object k) {
2179	>	return null;
2180	>	}
2181	>	}
2182	>
2183	>	/* ---------------- Table Initialization and Resizing -------------- */
2184	>
2185	>	/**
2186	>	* Initializes table, using the size recorded in sizeCtl.
2187	>	*/
2188	>	private final Node<K,V>[] initTable() {
2189	>	Node<K,V>[] tab; int sc;
2190	>	while ((tab = table) == null || tab.length == 0) {
2191	>	if ((sc = sizeCtl) < 0)
2192	>	Thread.yield(); // lost initialization race; just spin
2193	>	else if (U.compareAndSwapInt(this, SIZECTL, sc, -1)) {
2194	>	try {
2195	>	if ((tab = table) == null || tab.length == 0) {
2196	>	int n = (sc > 0) ? sc : DEFAULT_CAPACITY;
2197	>	@SuppressWarnings({"rawtypes","unchecked"})
2198	>	Node<K,V>[] nt = (Node<K,V>[])new Node[n];
2199	>	table = tab = nt;
2200	>	sc = n - (n >>> 2);
2201	>	}
2202	>	} finally {
2203	>	sizeCtl = sc;
2204	>	}
2205	>	break;
2206	>	}
2207	>	}
2208	>	return tab;
2209	>	}
2210	>
2211	>	/**
2212	>	* Adds to count, and if table is too small and not already
2213	>	* resizing, initiates transfer. If already resizing, helps
2214	>	* perform transfer if work is available.  Rechecks occupancy
2215	>	* after a transfer to see if another resize is already needed
2216	>	* because resizings are lagging additions.
2217	>	*
2218	>	* @param x the count to add
2219	>	* @param check if <0, don't check resize, if <= 1 only check if uncontended
2220	>	*/
2221	>	private final void addCount(long x, int check) {
2222	>	CounterCell[] as; long b, s;
2223	>	if ((as = counterCells) != null ||
2224	>	!U.compareAndSwapLong(this, BASECOUNT, b = baseCount, s = b + x)) {
2225	>	CounterHashCode hc; CounterCell a; long v; int m;
2226	>	boolean uncontended = true;
2227	>	if ((hc = threadCounterHashCode.get()) == null ||
2228	>	as == null || (m = as.length - 1) < 0 ||
2229	>	(a = as[m & hc.code]) == null ||
2230	>	!(uncontended =
2231	>	U.compareAndSwapLong(a, CELLVALUE, v = a.value, v + x))) {
2232	>	fullAddCount(x, hc, uncontended);
2233	>	return;
2234	>	}
2235	>	if (check <= 1)
2236	>	return;
2237	>	s = sumCount();
2238	>	}
2239	>	if (check >= 0) {
2240	>	Node<K,V>[] tab, nt; int sc;
2241	>	while (s >= (long)(sc = sizeCtl) && (tab = table) != null &&
2242	>	tab.length < MAXIMUM_CAPACITY) {
2243	>	if (sc < 0) {
2244	>	if (sc == -1 || transferIndex <= transferOrigin ||
2245	>	(nt = nextTable) == null)
2246		break;
2247	+	if (U.compareAndSwapInt(this, SIZECTL, sc, sc - 1))
2248	+	transfer(tab, nt);
2249		}
2250	<	} finally {
2251	<	resizing = 0;
2250	>	else if (U.compareAndSwapInt(this, SIZECTL, sc, -2))
2251	>	transfer(tab, null);
2252	>	s = sumCount();
2253		}
2254		}
2255	<	else if (table == null)
2256	<	Thread.yield(); // lost initialization race; just spin
2255	>	}
2256	>
2257	>	/**
2258	>	* Helps transfer if a resize is in progress.
2259	>	*/
2260	>	final Node<K,V>[] helpTransfer(Node<K,V>[] tab, Node<K,V> f) {
2261	>	Node<K,V>[] nextTab; int sc;
2262	>	if ((f instanceof ForwardingNode) &&
2263	>	(nextTab = ((ForwardingNode<K,V>)f).nextTable) != null) {
2264	>	if (nextTab == nextTable && tab == table &&
2265	>	transferIndex > transferOrigin && (sc = sizeCtl) < -1 &&
2266	>	U.compareAndSwapInt(this, SIZECTL, sc, sc - 1))
2267	>	transfer(tab, nextTab);
2268	>	return nextTab;
2269	>	}
2270		return table;
2271		}
2272
2273		/**
2274	<	* Implementation for putAll and constructor with Map
2275	<	* argument. Tries to first override initial capacity or grow
2276	<	* based on map size to pre-allocate table space.
2274	>	* Tries to presize table to accommodate the given number of elements.
2275	>	*
2276	>	* @param size number of elements (doesn't need to be perfectly accurate)
2277		*/
2278	<	private final void internalPutAll(Map<? extends K, ? extends V> m) {
2279	<	int s = m.size();
2280	<	grow((s >= (MAXIMUM_CAPACITY >>> 1)) ? s : s + (s >>> 1));
2281	<	for (Map.Entry<? extends K, ? extends V> e : m.entrySet()) {
2282	<	Object k = e.getKey();
2283	<	Object v = e.getValue();
2284	<	if (k == null || v == null)
2285	<	throw new NullPointerException();
2286	<	internalPut(k, v, true);
2278	>	private final void tryPresize(int size) {
2279	>	int c = (size >= (MAXIMUM_CAPACITY >>> 1)) ? MAXIMUM_CAPACITY :
2280	>	tableSizeFor(size + (size >>> 1) + 1);
2281	>	int sc;
2282	>	while ((sc = sizeCtl) >= 0) {
2283	>	Node<K,V>[] tab = table; int n;
2284	>	if (tab == null || (n = tab.length) == 0) {
2285	>	n = (sc > c) ? sc : c;
2286	>	if (U.compareAndSwapInt(this, SIZECTL, sc, -1)) {
2287	>	try {
2288	>	if (table == tab) {
2289	>	@SuppressWarnings({"rawtypes","unchecked"})
2290	>	Node<K,V>[] nt = (Node<K,V>[])new Node[n];
2291	>	table = nt;
2292	>	sc = n - (n >>> 2);
2293	>	}
2294	>	} finally {
2295	>	sizeCtl = sc;
2296	>	}
2297	>	}
2298	>	}
2299	>	else if (c <= sc || n >= MAXIMUM_CAPACITY)
2300	>	break;
2301	>	else if (tab == table &&
2302	>	U.compareAndSwapInt(this, SIZECTL, sc, -2))
2303	>	transfer(tab, null);
2304		}
2305		}
2306
2307		/**
2308	<	* Implementation for clear. Steps through each bin, removing all nodes.
2308	>	* Moves and/or copies the nodes in each bin to new table. See
2309	>	* above for explanation.
2310		*/
2311	<	private final void internalClear() {
2312	<	long deletions = 0L;
2313	<	int i = 0;
2314	<	Node[] tab = table;
2315	<	while (tab != null && i < tab.length) {
2316	<	Node e = tabAt(tab, i);
2317	<	if (e == null)
2318	<	++i;
2319	<	else if (e.hash < 0)
2320	<	tab = (Node[])e.key;
2311	>	private final void transfer(Node<K,V>[] tab, Node<K,V>[] nextTab) {
2312	>	int n = tab.length, stride;
2313	>	if ((stride = (NCPU > 1) ? (n >>> 3) / NCPU : n) < MIN_TRANSFER_STRIDE)
2314	>	stride = MIN_TRANSFER_STRIDE; // subdivide range
2315	>	if (nextTab == null) {            // initiating
2316	>	try {
2317	>	@SuppressWarnings({"rawtypes","unchecked"})
2318	>	Node<K,V>[] nt = (Node<K,V>[])new Node[n << 1];
2319	>	nextTab = nt;
2320	>	} catch (Throwable ex) {      // try to cope with OOME
2321	>	sizeCtl = Integer.MAX_VALUE;
2322	>	return;
2323	>	}
2324	>	nextTable = nextTab;
2325	>	transferOrigin = n;
2326	>	transferIndex = n;
2327	>	ForwardingNode<K,V> rev = new ForwardingNode<K,V>(tab);
2328	>	for (int k = n; k > 0;) {    // progressively reveal ready slots
2329	>	int nextk = (k > stride) ? k - stride : 0;
2330	>	for (int m = nextk; m < k; ++m)
2331	>	nextTab[m] = rev;
2332	>	for (int m = n + nextk; m < n + k; ++m)
2333	>	nextTab[m] = rev;
2334	>	U.putOrderedInt(this, TRANSFERORIGIN, k = nextk);
2335	>	}
2336	>	}
2337	>	int nextn = nextTab.length;
2338	>	ForwardingNode<K,V> fwd = new ForwardingNode<K,V>(nextTab);
2339	>	boolean advance = true;
2340	>	boolean finishing = false; // to ensure sweep before committing nextTab
2341	>	for (int i = 0, bound = 0;;) {
2342	>	int nextIndex, nextBound, fh; Node<K,V> f;
2343	>	while (advance) {
2344	>	if (--i >= bound || finishing)
2345	>	advance = false;
2346	>	else if ((nextIndex = transferIndex) <= transferOrigin) {
2347	>	i = -1;
2348	>	advance = false;
2349	>	}
2350	>	else if (U.compareAndSwapInt
2351	>	(this, TRANSFERINDEX, nextIndex,
2352	>	nextBound = (nextIndex > stride ?
2353	>	nextIndex - stride : 0))) {
2354	>	bound = nextBound;
2355	>	i = nextIndex - 1;
2356	>	advance = false;
2357	>	}
2358	>	}
2359	>	if (i < 0 || i >= n || i + n >= nextn) {
2360	>	if (finishing) {
2361	>	nextTable = null;
2362	>	table = nextTab;
2363	>	sizeCtl = (n << 1) - (n >>> 1);
2364	>	return;
2365	>	}
2366	>	for (int sc;;) {
2367	>	if (U.compareAndSwapInt(this, SIZECTL, sc = sizeCtl, ++sc)) {
2368	>	if (sc != -1)
2369	>	return;
2370	>	finishing = advance = true;
2371	>	i = n; // recheck before commit
2372	>	break;
2373	>	}
2374	>	}
2375	>	}
2376	>	else if ((f = tabAt(tab, i)) == null) {
2377	>	if (casTabAt(tab, i, null, fwd)) {
2378	>	setTabAt(nextTab, i, null);
2379	>	setTabAt(nextTab, i + n, null);
2380	>	advance = true;
2381	>	}
2382	>	}
2383	>	else if ((fh = f.hash) == MOVED)
2384	>	advance = true; // already processed
2385		else {
2386	<	boolean validated = false;
2387	<	synchronized (e) {
2388	<	if (tabAt(tab, i) == e) {
2389	<	validated = true;
2390	<	do {
2391	<	if (e.val != null) {
2392	<	e.val = null;
2393	<	++deletions;
2386	>	synchronized (f) {
2387	>	if (tabAt(tab, i) == f) {
2388	>	Node<K,V> ln, hn;
2389	>	if (fh >= 0) {
2390	>	int runBit = fh & n;
2391	>	Node<K,V> lastRun = f;
2392	>	for (Node<K,V> p = f.next; p != null; p = p.next) {
2393	>	int b = p.hash & n;
2394	>	if (b != runBit) {
2395	>	runBit = b;
2396	>	lastRun = p;
2397	>	}
2398	>	}
2399	>	if (runBit == 0) {
2400	>	ln = lastRun;
2401	>	hn = null;
2402		}
2403	<	} while ((e = e.next) != null);
2404	<	setTabAt(tab, i, null);
2403	>	else {
2404	>	hn = lastRun;
2405	>	ln = null;
2406	>	}
2407	>	for (Node<K,V> p = f; p != lastRun; p = p.next) {
2408	>	int ph = p.hash; K pk = p.key; V pv = p.val;
2409	>	if ((ph & n) == 0)
2410	>	ln = new Node<K,V>(ph, pk, pv, ln);
2411	>	else
2412	>	hn = new Node<K,V>(ph, pk, pv, hn);
2413	>	}
2414	>	setTabAt(nextTab, i, ln);
2415	>	setTabAt(nextTab, i + n, hn);
2416	>	setTabAt(tab, i, fwd);
2417	>	advance = true;
2418	>	}
2419	>	else if (f instanceof TreeBin) {
2420	>	TreeBin<K,V> t = (TreeBin<K,V>)f;
2421	>	TreeNode<K,V> lo = null, loTail = null;
2422	>	TreeNode<K,V> hi = null, hiTail = null;
2423	>	int lc = 0, hc = 0;
2424	>	for (Node<K,V> e = t.first; e != null; e = e.next) {
2425	>	int h = e.hash;
2426	>	TreeNode<K,V> p = new TreeNode<K,V>
2427	>	(h, e.key, e.val, null, null);
2428	>	if ((h & n) == 0) {
2429	>	if ((p.prev = loTail) == null)
2430	>	lo = p;
2431	>	else
2432	>	loTail.next = p;
2433	>	loTail = p;
2434	>	++lc;
2435	>	}
2436	>	else {
2437	>	if ((p.prev = hiTail) == null)
2438	>	hi = p;
2439	>	else
2440	>	hiTail.next = p;
2441	>	hiTail = p;
2442	>	++hc;
2443	>	}
2444	>	}
2445	>	ln = (lc <= UNTREEIFY_THRESHOLD) ? untreeify(lo) :
2446	>	(hc != 0) ? new TreeBin<K,V>(lo) : t;
2447	>	hn = (hc <= UNTREEIFY_THRESHOLD) ? untreeify(hi) :
2448	>	(lc != 0) ? new TreeBin<K,V>(hi) : t;
2449	>	setTabAt(nextTab, i, ln);
2450	>	setTabAt(nextTab, i + n, hn);
2451	>	setTabAt(tab, i, fwd);
2452	>	advance = true;
2453	>	}
2454		}
2455		}
2456	<	if (validated) {
2457	<	++i;
2458	<	if (deletions > THRESHOLD_OFFSET) { // bound lag in counts
2459	<	counter.add(-deletions);
2460	<	deletions = 0L;
2456	>	}
2457	>	}
2458	>	}
2459	>
2460	>	/* ---------------- Conversion from/to TreeBins -------------- */
2461	>
2462	>	/**
2463	>	* Replaces all linked nodes in bin at given index unless table is
2464	>	* too small, in which case resizes instead.
2465	>	*/
2466	>	private final void treeifyBin(Node<K,V>[] tab, int index) {
2467	>	Node<K,V> b; int n, sc;
2468	>	if (tab != null) {
2469	>	if ((n = tab.length) < MIN_TREEIFY_CAPACITY) {
2470	>	if (tab == table && (sc = sizeCtl) >= 0 &&
2471	>	U.compareAndSwapInt(this, SIZECTL, sc, -2))
2472	>	transfer(tab, null);
2473	>	}
2474	>	else if ((b = tabAt(tab, index)) != null && b.hash >= 0) {
2475	>	synchronized (b) {
2476	>	if (tabAt(tab, index) == b) {
2477	>	TreeNode<K,V> hd = null, tl = null;
2478	>	for (Node<K,V> e = b; e != null; e = e.next) {
2479	>	TreeNode<K,V> p =
2480	>	new TreeNode<K,V>(e.hash, e.key, e.val,
2481	>	null, null);
2482	>	if ((p.prev = tl) == null)
2483	>	hd = p;
2484	>	else
2485	>	tl.next = p;
2486	>	tl = p;
2487	>	}
2488	>	setTabAt(tab, index, new TreeBin<K,V>(hd));
2489		}
2490		}
2491		}
2492		}
725	–	if (deletions != 0L)
726	–	counter.add(-deletions);
2493		}
2494
2495		/**
2496	<	* Base class for key, value, and entry iterators, plus internal
731	<	* implementations of public traversal-based methods, to avoid
732	<	* duplicating traversal code.
2496	>	* Returns a list on non-TreeNodes replacing those in given list.
2497		*/
2498	<	class HashIterator {
2499	<	private Node next;          // the next entry to return
2500	<	private Node[] tab;         // current table; updated if resized
2501	<	private Node lastReturned;  // the last entry returned, for remove
2502	<	private Object nextVal;     // cached value of next
2503	<	private int index;          // index of bin to use next
2504	<	private int baseIndex;      // current index of initial table
2505	<	private final int baseSize; // initial table size
2498	>	static <K,V> Node<K,V> untreeify(Node<K,V> b) {
2499	>	Node<K,V> hd = null, tl = null;
2500	>	for (Node<K,V> q = b; q != null; q = q.next) {
2501	>	Node<K,V> p = new Node<K,V>(q.hash, q.key, q.val, null);
2502	>	if (tl == null)
2503	>	hd = p;
2504	>	else
2505	>	tl.next = p;
2506	>	tl = p;
2507	>	}
2508	>	return hd;
2509	>	}
2510
2511	<	HashIterator() {
2512	<	Node[] t = tab = table;
2513	<	if (t == null)
2514	<	baseSize = 0;
2515	<	else {
2516	<	baseSize = t.length;
2517	<	advance(null);
2518	<	}
2511	>	/* ---------------- TreeNodes -------------- */
2512	>
2513	>	/**
2514	>	* Nodes for use in TreeBins
2515	>	*/
2516	>	static final class TreeNode<K,V> extends Node<K,V> {
2517	>	TreeNode<K,V> parent;  // red-black tree links
2518	>	TreeNode<K,V> left;
2519	>	TreeNode<K,V> right;
2520	>	TreeNode<K,V> prev;    // needed to unlink next upon deletion
2521	>	boolean red;
2522	>
2523	>	TreeNode(int hash, K key, V val, Node<K,V> next,
2524	>	TreeNode<K,V> parent) {
2525	>	super(hash, key, val, next);
2526	>	this.parent = parent;
2527		}
2528
2529	<	public final boolean hasNext()         { return next != null; }
2530	<	public final boolean hasMoreElements() { return next != null; }
2529	>	Node<K,V> find(int h, Object k) {
2530	>	return findTreeNode(h, k, null);
2531	>	}
2532
2533		/**
2534	<	* Advances next.  Normally, iteration proceeds bin-by-bin
2535	<	* traversing lists.  However, if the table has been resized,
759	<	* then all future steps must traverse both the bin at the
760	<	* current index as well as at (index + baseSize); and so on
761	<	* for further resizings. To paranoically cope with potential
762	<	* (improper) sharing of iterators across threads, table reads
763	<	* are bounds-checked.
2534	>	* Returns the TreeNode (or null if not found) for the given key
2535	>	* starting at given root.
2536		*/
2537	<	final void advance(Node e) {
2538	<	for (;;) {
2539	<	Node[] t; int i; // for bounds checks
2540	<	if (e != null) {
2541	<	Object ek = e.key, ev = e.val;
2542	<	if (ev != null && ek != null) {
2543	<	nextVal = ev;
2544	<	next = e;
2537	>	final TreeNode<K,V> findTreeNode(int h, Object k, Class<?> kc) {
2538	>	if (k != null) {
2539	>	TreeNode<K,V> p = this;
2540	>	do  {
2541	>	int ph, dir; K pk; TreeNode<K,V> q;
2542	>	TreeNode<K,V> pl = p.left, pr = p.right;
2543	>	if ((ph = p.hash) > h)
2544	>	p = pl;
2545	>	else if (ph < h)
2546	>	p = pr;
2547	>	else if ((pk = p.key) == k || (pk != null && k.equals(pk)))
2548	>	return p;
2549	>	else if (pl == null && pr == null)
2550		break;
2551	<	}
2552	<	e = e.next;
2553	<	}
2554	<	else if (baseIndex < baseSize && (t = tab) != null &&
2555	<	t.length > (i = index) && i >= 0) {
2556	<	if ((e = tabAt(t, i)) != null && e.hash < 0) {
2557	<	tab = (Node[])e.key;
2558	<	e = null;
2559	<	}
783	<	else if (i + baseSize < t.length)
784	<	index += baseSize;    // visit forwarded upper slots
2551	>	else if ((kc != null ||
2552	>	(kc = comparableClassFor(k)) != null) &&
2553	>	(dir = compareComparables(kc, k, pk)) != 0)
2554	>	p = (dir < 0) ? pl : pr;
2555	>	else if (pl == null)
2556	>	p = pr;
2557	>	else if (pr == null ||
2558	>	(q = pr.findTreeNode(h, k, kc)) == null)
2559	>	p = pl;
2560		else
2561	<	index = ++baseIndex;
2561	>	return q;
2562	>	} while (p != null);
2563	>	}
2564	>	return null;
2565	>	}
2566	>	}
2567	>
2568	>	/* ---------------- TreeBins -------------- */
2569	>
2570	>	/**
2571	>	* TreeNodes used at the heads of bins. TreeBins do not hold user
2572	>	* keys or values, but instead point to list of TreeNodes and
2573	>	* their root. They also maintain a parasitic read-write lock
2574	>	* forcing writers (who hold bin lock) to wait for readers (who do
2575	>	* not) to complete before tree restructuring operations.
2576	>	*/
2577	>	static final class TreeBin<K,V> extends Node<K,V> {
2578	>	TreeNode<K,V> root;
2579	>	volatile TreeNode<K,V> first;
2580	>	volatile Thread waiter;
2581	>	volatile int lockState;
2582	>	// values for lockState
2583	>	static final int WRITER = 1; // set while holding write lock
2584	>	static final int WAITER = 2; // set when waiting for write lock
2585	>	static final int READER = 4; // increment value for setting read lock
2586	>
2587	>	/**
2588	>	* Creates bin with initial set of nodes headed by b.
2589	>	*/
2590	>	TreeBin(TreeNode<K,V> b) {
2591	>	super(TREEBIN, null, null, null);
2592	>	this.first = b;
2593	>	TreeNode<K,V> r = null;
2594	>	for (TreeNode<K,V> x = b, next; x != null; x = next) {
2595	>	next = (TreeNode<K,V>)x.next;
2596	>	x.left = x.right = null;
2597	>	if (r == null) {
2598	>	x.parent = null;
2599	>	x.red = false;
2600	>	r = x;
2601		}
2602		else {
2603	<	next = null;
2604	<	break;
2603	>	Object key = x.key;
2604	>	int hash = x.hash;
2605	>	Class<?> kc = null;
2606	>	for (TreeNode<K,V> p = r;;) {
2607	>	int dir, ph;
2608	>	if ((ph = p.hash) > hash)
2609	>	dir = -1;
2610	>	else if (ph < hash)
2611	>	dir = 1;
2612	>	else if ((kc != null ||
2613	>	(kc = comparableClassFor(key)) != null))
2614	>	dir = compareComparables(kc, key, p.key);
2615	>	else
2616	>	dir = 0;
2617	>	TreeNode<K,V> xp = p;
2618	>	if ((p = (dir <= 0) ? p.left : p.right) == null) {
2619	>	x.parent = xp;
2620	>	if (dir <= 0)
2621	>	xp.left = x;
2622	>	else
2623	>	xp.right = x;
2624	>	r = balanceInsertion(r, x);
2625	>	break;
2626	>	}
2627	>	}
2628		}
2629		}
2630	+	this.root = r;
2631		}
2632
2633	<	final Object nextKey() {
2634	<	Node e = next;
2635	<	if (e == null)
2636	<	throw new NoSuchElementException();
2637	<	Object k = e.key;
2638	<	advance((lastReturned = e).next);
801	<	return k;
2633	>	/**
2634	>	* Acquires write lock for tree restructuring.
2635	>	*/
2636	>	private final void lockRoot() {
2637	>	if (!U.compareAndSwapInt(this, LOCKSTATE, 0, WRITER))
2638	>	contendedLock(); // offload to separate method
2639		}
2640
2641	<	final Object nextValue() {
2642	<	Node e = next;
2643	<	if (e == null)
2644	<	throw new NoSuchElementException();
2645	<	Object v = nextVal;
809	<	advance((lastReturned = e).next);
810	<	return v;
2641	>	/**
2642	>	* Releases write lock for tree restructuring.
2643	>	*/
2644	>	private final void unlockRoot() {
2645	>	lockState = 0;
2646		}
2647
2648	<	final WriteThroughEntry nextEntry() {
2649	<	Node e = next;
2650	<	if (e == null)
2651	<	throw new NoSuchElementException();
2652	<	WriteThroughEntry entry =
2653	<	new WriteThroughEntry(e.key, nextVal);
2654	<	advance((lastReturned = e).next);
2655	<	return entry;
2648	>	/**
2649	>	* Possibly blocks awaiting root lock.
2650	>	*/
2651	>	private final void contendedLock() {
2652	>	boolean waiting = false;
2653	>	for (int s;;) {
2654	>	if (((s = lockState) & WRITER) == 0) {
2655	>	if (U.compareAndSwapInt(this, LOCKSTATE, s, WRITER)) {
2656	>	if (waiting)
2657	>	waiter = null;
2658	>	return;
2659	>	}
2660	>	}
2661	>	else if ((s | WAITER) == 0) {
2662	>	if (U.compareAndSwapInt(this, LOCKSTATE, s, s | WAITER)) {
2663	>	waiting = true;
2664	>	waiter = Thread.currentThread();
2665	>	}
2666	>	}
2667	>	else if (waiting)
2668	>	LockSupport.park(this);
2669	>	}
2670		}
2671
2672	<	public final void remove() {
2673	<	if (lastReturned == null)
2674	<	throw new IllegalStateException();
2675	<	ConcurrentHashMapV8.this.remove(lastReturned.key);
2676	<	lastReturned = null;
2672	>	/**
2673	>	* Returns matching node or null if none. Tries to search
2674	>	* using tree comparisons from root, but continues linear
2675	>	* search when lock not available.
2676	>	*/
2677	>	final Node<K,V> find(int h, Object k) {
2678	>	if (k != null) {
2679	>	for (Node<K,V> e = first; e != null; e = e.next) {
2680	>	int s; K ek;
2681	>	if (((s = lockState) & (WAITER|WRITER)) != 0) {
2682	>	if (e.hash == h &&
2683	>	((ek = e.key) == k || (ek != null && k.equals(ek))))
2684	>	return e;
2685	>	}
2686	>	else if (U.compareAndSwapInt(this, LOCKSTATE, s,
2687	>	s + READER)) {
2688	>	TreeNode<K,V> r, p;
2689	>	try {
2690	>	p = ((r = root) == null ? null :
2691	>	r.findTreeNode(h, k, null));
2692	>	} finally {
2693	>	Thread w;
2694	>	int ls;
2695	>	do {} while (!U.compareAndSwapInt
2696	>	(this, LOCKSTATE,
2697	>	ls = lockState, ls - READER));
2698	>	if (ls == (READER|WAITER) && (w = waiter) != null)
2699	>	LockSupport.unpark(w);
2700	>	}
2701	>	return p;
2702	>	}
2703	>	}
2704	>	}
2705	>	return null;
2706		}
2707
2708	<	/** Helper for serialization */
2709	<	final void writeEntries(java.io.ObjectOutputStream s)
2710	<	throws java.io.IOException {
2711	<	Node e;
2712	<	while ((e = next) != null) {
2713	<	s.writeObject(e.key);
2714	<	s.writeObject(nextVal);
2715	<	advance(e.next);
2708	>	/**
2709	>	* Finds or adds a node.
2710	>	* @return null if added
2711	>	*/
2712	>	final TreeNode<K,V> putTreeVal(int h, K k, V v) {
2713	>	Class<?> kc = null;
2714	>	for (TreeNode<K,V> p = root;;) {
2715	>	int dir, ph; K pk; TreeNode<K,V> q, pr;
2716	>	if (p == null) {
2717	>	first = root = new TreeNode<K,V>(h, k, v, null, null);
2718	>	break;
2719	>	}
2720	>	else if ((ph = p.hash) > h)
2721	>	dir = -1;
2722	>	else if (ph < h)
2723	>	dir = 1;
2724	>	else if ((pk = p.key) == k || (pk != null && k.equals(pk)))
2725	>	return p;
2726	>	else if ((kc == null &&
2727	>	(kc = comparableClassFor(k)) == null) ||
2728	>	(dir = compareComparables(kc, k, pk)) == 0) {
2729	>	if (p.left == null)
2730	>	dir = 1;
2731	>	else if ((pr = p.right) == null ||
2732	>	(q = pr.findTreeNode(h, k, kc)) == null)
2733	>	dir = -1;
2734	>	else
2735	>	return q;
2736	>	}
2737	>	TreeNode<K,V> xp = p;
2738	>	if ((p = (dir < 0) ? p.left : p.right) == null) {
2739	>	TreeNode<K,V> x, f = first;
2740	>	first = x = new TreeNode<K,V>(h, k, v, f, xp);
2741	>	if (f != null)
2742	>	f.prev = x;
2743	>	if (dir < 0)
2744	>	xp.left = x;
2745	>	else
2746	>	xp.right = x;
2747	>	if (!xp.red)
2748	>	x.red = true;
2749	>	else {
2750	>	lockRoot();
2751	>	try {
2752	>	root = balanceInsertion(root, x);
2753	>	} finally {
2754	>	unlockRoot();
2755	>	}
2756	>	}
2757	>	break;
2758	>	}
2759		}
2760	+	assert checkInvariants(root);
2761	+	return null;
2762		}
2763
2764	<	/** Helper for containsValue */
2765	<	final boolean containsVal(Object value) {
2766	<	if (value != null) {
2767	<	Node e;
2768	<	while ((e = next) != null) {
2769	<	Object v = nextVal;
2770	<	if (value == v || value.equals(v))
2771	<	return true;
2772	<	advance(e.next);
2764	>	/**
2765	>	* Removes the given node, that must be present before this
2766	>	* call.  This is messier than typical red-black deletion code
2767	>	* because we cannot swap the contents of an interior node
2768	>	* with a leaf successor that is pinned by "next" pointers
2769	>	* that are accessible independently of lock. So instead we
2770	>	* swap the tree linkages.
2771	>	*
2772	>	* @return true if now too small, so should be untreeified
2773	>	*/
2774	>	final boolean removeTreeNode(TreeNode<K,V> p) {
2775	>	TreeNode<K,V> next = (TreeNode<K,V>)p.next;
2776	>	TreeNode<K,V> pred = p.prev;  // unlink traversal pointers
2777	>	TreeNode<K,V> r, rl;
2778	>	if (pred == null)
2779	>	first = next;
2780	>	else
2781	>	pred.next = next;
2782	>	if (next != null)
2783	>	next.prev = pred;
2784	>	if (first == null) {
2785	>	root = null;
2786	>	return true;
2787	>	}
2788	>	if ((r = root) == null || r.right == null || // too small
2789	>	(rl = r.left) == null || rl.left == null)
2790	>	return true;
2791	>	lockRoot();
2792	>	try {
2793	>	TreeNode<K,V> replacement;
2794	>	TreeNode<K,V> pl = p.left;
2795	>	TreeNode<K,V> pr = p.right;
2796	>	if (pl != null && pr != null) {
2797	>	TreeNode<K,V> s = pr, sl;
2798	>	while ((sl = s.left) != null) // find successor
2799	>	s = sl;
2800	>	boolean c = s.red; s.red = p.red; p.red = c; // swap colors
2801	>	TreeNode<K,V> sr = s.right;
2802	>	TreeNode<K,V> pp = p.parent;
2803	>	if (s == pr) { // p was s's direct parent
2804	>	p.parent = s;
2805	>	s.right = p;
2806	>	}
2807	>	else {
2808	>	TreeNode<K,V> sp = s.parent;
2809	>	if ((p.parent = sp) != null) {
2810	>	if (s == sp.left)
2811	>	sp.left = p;
2812	>	else
2813	>	sp.right = p;
2814	>	}
2815	>	if ((s.right = pr) != null)
2816	>	pr.parent = s;
2817	>	}
2818	>	p.left = null;
2819	>	if ((p.right = sr) != null)
2820	>	sr.parent = p;
2821	>	if ((s.left = pl) != null)
2822	>	pl.parent = s;
2823	>	if ((s.parent = pp) == null)
2824	>	r = s;
2825	>	else if (p == pp.left)
2826	>	pp.left = s;
2827	>	else
2828	>	pp.right = s;
2829	>	if (sr != null)
2830	>	replacement = sr;
2831	>	else
2832	>	replacement = p;
2833	>	}
2834	>	else if (pl != null)
2835	>	replacement = pl;
2836	>	else if (pr != null)
2837	>	replacement = pr;
2838	>	else
2839	>	replacement = p;
2840	>	if (replacement != p) {
2841	>	TreeNode<K,V> pp = replacement.parent = p.parent;
2842	>	if (pp == null)
2843	>	r = replacement;
2844	>	else if (p == pp.left)
2845	>	pp.left = replacement;
2846	>	else
2847	>	pp.right = replacement;
2848	>	p.left = p.right = p.parent = null;
2849		}
2850	+
2851	+	root = (p.red) ? r : balanceDeletion(r, replacement);
2852	+
2853	+	if (p == replacement) {  // detach pointers
2854	+	TreeNode<K,V> pp;
2855	+	if ((pp = p.parent) != null) {
2856	+	if (p == pp.left)
2857	+	pp.left = null;
2858	+	else if (p == pp.right)
2859	+	pp.right = null;
2860	+	p.parent = null;
2861	+	}
2862	+	}
2863	+	} finally {
2864	+	unlockRoot();
2865		}
2866	+	assert checkInvariants(root);
2867		return false;
2868		}
2869
2870	<	/** Helper for Map.hashCode */
2871	<	final int mapHashCode() {
2872	<	int h = 0;
2873	<	Node e;
2874	<	while ((e = next) != null) {
2875	<	h += e.key.hashCode() ^ nextVal.hashCode();
2876	<	advance(e.next);
2870	>	/* ------------------------------------------------------------ */
2871	>	// Red-black tree methods, all adapted from CLR
2872	>
2873	>	static <K,V> TreeNode<K,V> rotateLeft(TreeNode<K,V> root,
2874	>	TreeNode<K,V> p) {
2875	>	TreeNode<K,V> r, pp, rl;
2876	>	if (p != null && (r = p.right) != null) {
2877	>	if ((rl = p.right = r.left) != null)
2878	>	rl.parent = p;
2879	>	if ((pp = r.parent = p.parent) == null)
2880	>	(root = r).red = false;
2881	>	else if (pp.left == p)
2882	>	pp.left = r;
2883	>	else
2884	>	pp.right = r;
2885	>	r.left = p;
2886	>	p.parent = r;
2887		}
2888	<	return h;
2888	>	return root;
2889		}
2890
2891	<	/** Helper for Map.toString */
2892	<	final String mapToString() {
2893	<	Node e = next;
2894	<	if (e == null)
2895	<	return "{}";
2896	<	StringBuilder sb = new StringBuilder();
2897	<	sb.append('{');
2898	<	for (;;) {
2899	<	sb.append(e.key   == this ? "(this Map)" : e.key);
2900	<	sb.append('=');
876	<	sb.append(nextVal == this ? "(this Map)" : nextVal);
877	<	advance(e.next);
878	<	if ((e = next) != null)
879	<	sb.append(',').append(' ');
2891	>	static <K,V> TreeNode<K,V> rotateRight(TreeNode<K,V> root,
2892	>	TreeNode<K,V> p) {
2893	>	TreeNode<K,V> l, pp, lr;
2894	>	if (p != null && (l = p.left) != null) {
2895	>	if ((lr = p.left = l.right) != null)
2896	>	lr.parent = p;
2897	>	if ((pp = l.parent = p.parent) == null)
2898	>	(root = l).red = false;
2899	>	else if (pp.right == p)
2900	>	pp.right = l;
2901		else
2902	<	return sb.append('}').toString();
2902	>	pp.left = l;
2903	>	l.right = p;
2904	>	p.parent = l;
2905	>	}
2906	>	return root;
2907	>	}
2908	>
2909	>	static <K,V> TreeNode<K,V> balanceInsertion(TreeNode<K,V> root,
2910	>	TreeNode<K,V> x) {
2911	>	x.red = true;
2912	>	for (TreeNode<K,V> xp, xpp, xppl, xppr;;) {
2913	>	if ((xp = x.parent) == null) {
2914	>	x.red = false;
2915	>	return x;
2916	>	}
2917	>	else if (!xp.red || (xpp = xp.parent) == null)
2918	>	return root;
2919	>	if (xp == (xppl = xpp.left)) {
2920	>	if ((xppr = xpp.right) != null && xppr.red) {
2921	>	xppr.red = false;
2922	>	xp.red = false;
2923	>	xpp.red = true;
2924	>	x = xpp;
2925	>	}
2926	>	else {
2927	>	if (x == xp.right) {
2928	>	root = rotateLeft(root, x = xp);
2929	>	xpp = (xp = x.parent) == null ? null : xp.parent;
2930	>	}
2931	>	if (xp != null) {
2932	>	xp.red = false;
2933	>	if (xpp != null) {
2934	>	xpp.red = true;
2935	>	root = rotateRight(root, xpp);
2936	>	}
2937	>	}
2938	>	}
2939	>	}
2940	>	else {
2941	>	if (xppl != null && xppl.red) {
2942	>	xppl.red = false;
2943	>	xp.red = false;
2944	>	xpp.red = true;
2945	>	x = xpp;
2946	>	}
2947	>	else {
2948	>	if (x == xp.left) {
2949	>	root = rotateRight(root, x = xp);
2950	>	xpp = (xp = x.parent) == null ? null : xp.parent;
2951	>	}
2952	>	if (xp != null) {
2953	>	xp.red = false;
2954	>	if (xpp != null) {
2955	>	xpp.red = true;
2956	>	root = rotateLeft(root, xpp);
2957	>	}
2958	>	}
2959	>	}
2960	>	}
2961	>	}
2962	>	}
2963	>
2964	>	static <K,V> TreeNode<K,V> balanceDeletion(TreeNode<K,V> root,
2965	>	TreeNode<K,V> x) {
2966	>	for (TreeNode<K,V> xp, xpl, xpr;;)  {
2967	>	if (x == null || x == root)
2968	>	return root;
2969	>	else if ((xp = x.parent) == null) {
2970	>	x.red = false;
2971	>	return x;
2972	>	}
2973	>	else if (x.red) {
2974	>	x.red = false;
2975	>	return root;
2976	>	}
2977	>	else if ((xpl = xp.left) == x) {
2978	>	if ((xpr = xp.right) != null && xpr.red) {
2979	>	xpr.red = false;
2980	>	xp.red = true;
2981	>	root = rotateLeft(root, xp);
2982	>	xpr = (xp = x.parent) == null ? null : xp.right;
2983	>	}
2984	>	if (xpr == null)
2985	>	x = xp;
2986	>	else {
2987	>	TreeNode<K,V> sl = xpr.left, sr = xpr.right;
2988	>	if ((sr == null || !sr.red) &&
2989	>	(sl == null || !sl.red)) {
2990	>	xpr.red = true;
2991	>	x = xp;
2992	>	}
2993	>	else {
2994	>	if (sr == null || !sr.red) {
2995	>	if (sl != null)
2996	>	sl.red = false;
2997	>	xpr.red = true;
2998	>	root = rotateRight(root, xpr);
2999	>	xpr = (xp = x.parent) == null ?
3000	>	null : xp.right;
3001	>	}
3002	>	if (xpr != null) {
3003	>	xpr.red = (xp == null) ? false : xp.red;
3004	>	if ((sr = xpr.right) != null)
3005	>	sr.red = false;
3006	>	}
3007	>	if (xp != null) {
3008	>	xp.red = false;
3009	>	root = rotateLeft(root, xp);
3010	>	}
3011	>	x = root;
3012	>	}
3013	>	}
3014	>	}
3015	>	else { // symmetric
3016	>	if (xpl != null && xpl.red) {
3017	>	xpl.red = false;
3018	>	xp.red = true;
3019	>	root = rotateRight(root, xp);
3020	>	xpl = (xp = x.parent) == null ? null : xp.left;
3021	>	}
3022	>	if (xpl == null)
3023	>	x = xp;
3024	>	else {
3025	>	TreeNode<K,V> sl = xpl.left, sr = xpl.right;
3026	>	if ((sl == null || !sl.red) &&
3027	>	(sr == null || !sr.red)) {
3028	>	xpl.red = true;
3029	>	x = xp;
3030	>	}
3031	>	else {
3032	>	if (sl == null || !sl.red) {
3033	>	if (sr != null)
3034	>	sr.red = false;
3035	>	xpl.red = true;
3036	>	root = rotateLeft(root, xpl);
3037	>	xpl = (xp = x.parent) == null ?
3038	>	null : xp.left;
3039	>	}
3040	>	if (xpl != null) {
3041	>	xpl.red = (xp == null) ? false : xp.red;
3042	>	if ((sl = xpl.left) != null)
3043	>	sl.red = false;
3044	>	}
3045	>	if (xp != null) {
3046	>	xp.red = false;
3047	>	root = rotateRight(root, xp);
3048	>	}
3049	>	x = root;
3050	>	}
3051	>	}
3052	>	}
3053	>	}
3054	>	}
3055	>
3056	>	/**
3057	>	* Recursive invariant check
3058	>	*/
3059	>	static <K,V> boolean checkInvariants(TreeNode<K,V> t) {
3060	>	TreeNode<K,V> tp = t.parent, tl = t.left, tr = t.right,
3061	>	tb = t.prev, tn = (TreeNode<K,V>)t.next;
3062	>	if (tb != null && tb.next != t)
3063	>	return false;
3064	>	if (tn != null && tn.prev != t)
3065	>	return false;
3066	>	if (tp != null && t != tp.left && t != tp.right)
3067	>	return false;
3068	>	if (tl != null && (tl.parent != t || tl.hash > t.hash))
3069	>	return false;
3070	>	if (tr != null && (tr.parent != t || tr.hash < t.hash))
3071	>	return false;
3072	>	if (t.red && tl != null && tl.red && tr != null && tr.red)
3073	>	return false;
3074	>	if (tl != null && !checkInvariants(tl))
3075	>	return false;
3076	>	if (tr != null && !checkInvariants(tr))
3077	>	return false;
3078	>	return true;
3079	>	}
3080	>
3081	>	private static final sun.misc.Unsafe U;
3082	>	private static final long LOCKSTATE;
3083	>	static {
3084	>	try {
3085	>	U = getUnsafe();
3086	>	Class<?> k = TreeBin.class;
3087	>	LOCKSTATE = U.objectFieldOffset
3088	>	(k.getDeclaredField("lockState"));
3089	>	} catch (Exception e) {
3090	>	throw new Error(e);
3091		}
3092		}
3093		}
3094
3095	<	/* ---------------- Public operations -------------- */
3095	>	/* ----------------Table Traversal -------------- */
3096
3097		/**
3098	<	* Creates a new, empty map with the specified initial
3099	<	* capacity, load factor and concurrency level.
3098	>	* Encapsulates traversal for methods such as containsValue; also
3099	>	* serves as a base class for other iterators and spliterators.
3100		*
3101	<	* @param initialCapacity the initial capacity. The implementation
3102	<	* performs internal sizing to accommodate this many elements.
3103	<	* @param loadFactor  the load factor threshold, used to control resizing.
3104	<	* Resizing may be performed when the average number of elements per
3105	<	* bin exceeds this threshold.
3106	<	* @param concurrencyLevel the estimated number of concurrently
3107	<	* updating threads. The implementation may use this value as
3108	<	* a sizing hint.
3109	<	* @throws IllegalArgumentException if the initial capacity is
3110	<	* negative or the load factor or concurrencyLevel are
3111	<	* nonpositive.
3112	<	*/
3113	<	public ConcurrentHashMapV8(int initialCapacity,
3114	<	float loadFactor, int concurrencyLevel) {
3115	<	if (!(loadFactor > 0) || initialCapacity < 0 || concurrencyLevel <= 0)
3116	<	throw new IllegalArgumentException();
3117	<	this.initCap = initialCapacity;
3118	<	this.loadFactor = loadFactor;
3119	<	this.counter = new LongAdder();
3101	>	* Method advance visits once each still-valid node that was
3102	>	* reachable upon iterator construction. It might miss some that
3103	>	* were added to a bin after the bin was visited, which is OK wrt
3104	>	* consistency guarantees. Maintaining this property in the face
3105	>	* of possible ongoing resizes requires a fair amount of
3106	>	* bookkeeping state that is difficult to optimize away amidst
3107	>	* volatile accesses.  Even so, traversal maintains reasonable
3108	>	* throughput.
3109	>	*
3110	>	* Normally, iteration proceeds bin-by-bin traversing lists.
3111	>	* However, if the table has been resized, then all future steps
3112	>	* must traverse both the bin at the current index as well as at
3113	>	* (index + baseSize); and so on for further resizings. To
3114	>	* paranoically cope with potential sharing by users of iterators
3115	>	* across threads, iteration terminates if a bounds checks fails
3116	>	* for a table read.
3117	>	*/
3118	>	static class Traverser<K,V> {
3119	>	Node<K,V>[] tab;        // current table; updated if resized
3120	>	Node<K,V> next;         // the next entry to use
3121	>	int index;              // index of bin to use next
3122	>	int baseIndex;          // current index of initial table
3123	>	int baseLimit;          // index bound for initial table
3124	>	final int baseSize;     // initial table size
3125	>
3126	>	Traverser(Node<K,V>[] tab, int size, int index, int limit) {
3127	>	this.tab = tab;
3128	>	this.baseSize = size;
3129	>	this.baseIndex = this.index = index;
3130	>	this.baseLimit = limit;
3131	>	this.next = null;
3132	>	}
3133	>
3134	>	/**
3135	>	* Advances if possible, returning next valid node, or null if none.
3136	>	*/
3137	>	final Node<K,V> advance() {
3138	>	Node<K,V> e;
3139	>	if ((e = next) != null)
3140	>	e = e.next;
3141	>	for (;;) {
3142	>	Node<K,V>[] t; int i, n; K ek;  // must use locals in checks
3143	>	if (e != null)
3144	>	return next = e;
3145	>	if (baseIndex >= baseLimit || (t = tab) == null ||
3146	>	(n = t.length) <= (i = index) || i < 0)
3147	>	return next = null;
3148	>	if ((e = tabAt(t, index)) != null && e.hash < 0) {
3149	>	if (e instanceof ForwardingNode) {
3150	>	tab = ((ForwardingNode<K,V>)e).nextTable;
3151	>	e = null;
3152	>	continue;
3153	>	}
3154	>	else if (e instanceof TreeBin)
3155	>	e = ((TreeBin<K,V>)e).first;
3156	>	else
3157	>	e = null;
3158	>	}
3159	>	if ((index += baseSize) >= n)
3160	>	index = ++baseIndex;    // visit upper slots if present
3161	>	}
3162	>	}
3163		}
3164
3165		/**
3166	<	* Creates a new, empty map with the specified initial capacity
3167	<	* and load factor and with the default concurrencyLevel (16).
916	<	*
917	<	* @param initialCapacity The implementation performs internal
918	<	* sizing to accommodate this many elements.
919	<	* @param loadFactor  the load factor threshold, used to control resizing.
920	<	* Resizing may be performed when the average number of elements per
921	<	* bin exceeds this threshold.
922	<	* @throws IllegalArgumentException if the initial capacity of
923	<	* elements is negative or the load factor is nonpositive
924	<	*
925	<	* @since 1.6
3166	>	* Base of key, value, and entry Iterators. Adds fields to
3167	>	* Traverser to support iterator.remove.
3168		*/
3169	<	public ConcurrentHashMapV8(int initialCapacity, float loadFactor) {
3170	<	this(initialCapacity, loadFactor, DEFAULT_CONCURRENCY_LEVEL);
3169	>	static class BaseIterator<K,V> extends Traverser<K,V> {
3170	>	final ConcurrentHashMapV8<K,V> map;
3171	>	Node<K,V> lastReturned;
3172	>	BaseIterator(Node<K,V>[] tab, int size, int index, int limit,
3173	>	ConcurrentHashMapV8<K,V> map) {
3174	>	super(tab, size, index, limit);
3175	>	this.map = map;
3176	>	advance();
3177	>	}
3178	>
3179	>	public final boolean hasNext() { return next != null; }
3180	>	public final boolean hasMoreElements() { return next != null; }
3181	>
3182	>	public final void remove() {
3183	>	Node<K,V> p;
3184	>	if ((p = lastReturned) == null)
3185	>	throw new IllegalStateException();
3186	>	lastReturned = null;
3187	>	map.replaceNode(p.key, null, null);
3188	>	}
3189	>	}
3190	>
3191	>	static final class KeyIterator<K,V> extends BaseIterator<K,V>
3192	>	implements Iterator<K>, Enumeration<K> {
3193	>	KeyIterator(Node<K,V>[] tab, int index, int size, int limit,
3194	>	ConcurrentHashMapV8<K,V> map) {
3195	>	super(tab, index, size, limit, map);
3196	>	}
3197	>
3198	>	public final K next() {
3199	>	Node<K,V> p;
3200	>	if ((p = next) == null)
3201	>	throw new NoSuchElementException();
3202	>	K k = p.key;
3203	>	lastReturned = p;
3204	>	advance();
3205	>	return k;
3206	>	}
3207	>
3208	>	public final K nextElement() { return next(); }
3209	>	}
3210	>
3211	>	static final class ValueIterator<K,V> extends BaseIterator<K,V>
3212	>	implements Iterator<V>, Enumeration<V> {
3213	>	ValueIterator(Node<K,V>[] tab, int index, int size, int limit,
3214	>	ConcurrentHashMapV8<K,V> map) {
3215	>	super(tab, index, size, limit, map);
3216	>	}
3217	>
3218	>	public final V next() {
3219	>	Node<K,V> p;
3220	>	if ((p = next) == null)
3221	>	throw new NoSuchElementException();
3222	>	V v = p.val;
3223	>	lastReturned = p;
3224	>	advance();
3225	>	return v;
3226	>	}
3227	>
3228	>	public final V nextElement() { return next(); }
3229	>	}
3230	>
3231	>	static final class EntryIterator<K,V> extends BaseIterator<K,V>
3232	>	implements Iterator<Map.Entry<K,V>> {
3233	>	EntryIterator(Node<K,V>[] tab, int index, int size, int limit,
3234	>	ConcurrentHashMapV8<K,V> map) {
3235	>	super(tab, index, size, limit, map);
3236	>	}
3237	>
3238	>	public final Map.Entry<K,V> next() {
3239	>	Node<K,V> p;
3240	>	if ((p = next) == null)
3241	>	throw new NoSuchElementException();
3242	>	K k = p.key;
3243	>	V v = p.val;
3244	>	lastReturned = p;
3245	>	advance();
3246	>	return new MapEntry<K,V>(k, v, map);
3247	>	}
3248		}
3249
3250		/**
3251	<	* Creates a new, empty map with the specified initial capacity,
933	<	* and with default load factor (0.75) and concurrencyLevel (16).
934	<	*
935	<	* @param initialCapacity the initial capacity. The implementation
936	<	* performs internal sizing to accommodate this many elements.
937	<	* @throws IllegalArgumentException if the initial capacity of
938	<	* elements is negative.
3251	>	* Exported Entry for EntryIterator
3252		*/
3253	<	public ConcurrentHashMapV8(int initialCapacity) {
3254	<	this(initialCapacity, DEFAULT_LOAD_FACTOR, DEFAULT_CONCURRENCY_LEVEL);
3253	>	static final class MapEntry<K,V> implements Map.Entry<K,V> {
3254	>	final K key; // non-null
3255	>	V val;       // non-null
3256	>	final ConcurrentHashMapV8<K,V> map;
3257	>	MapEntry(K key, V val, ConcurrentHashMapV8<K,V> map) {
3258	>	this.key = key;
3259	>	this.val = val;
3260	>	this.map = map;
3261	>	}
3262	>	public K getKey()        { return key; }
3263	>	public V getValue()      { return val; }
3264	>	public int hashCode()    { return key.hashCode() ^ val.hashCode(); }
3265	>	public String toString() { return key + "=" + val; }
3266	>
3267	>	public boolean equals(Object o) {
3268	>	Object k, v; Map.Entry<?,?> e;
3269	>	return ((o instanceof Map.Entry) &&
3270	>	(k = (e = (Map.Entry<?,?>)o).getKey()) != null &&
3271	>	(v = e.getValue()) != null &&
3272	>	(k == key || k.equals(key)) &&
3273	>	(v == val || v.equals(val)));
3274	>	}
3275	>
3276	>	/**
3277	>	* Sets our entry's value and writes through to the map. The
3278	>	* value to return is somewhat arbitrary here. Since we do not
3279	>	* necessarily track asynchronous changes, the most recent
3280	>	* "previous" value could be different from what we return (or
3281	>	* could even have been removed, in which case the put will
3282	>	* re-establish). We do not and cannot guarantee more.
3283	>	*/
3284	>	public V setValue(V value) {
3285	>	if (value == null) throw new NullPointerException();
3286	>	V v = val;
3287	>	val = value;
3288	>	map.put(key, value);
3289	>	return v;
3290	>	}
3291		}
3292
3293	+	static final class KeySpliterator<K,V> extends Traverser<K,V>
3294	+	implements ConcurrentHashMapSpliterator<K> {
3295	+	long est;               // size estimate
3296	+	KeySpliterator(Node<K,V>[] tab, int size, int index, int limit,
3297	+	long est) {
3298	+	super(tab, size, index, limit);
3299	+	this.est = est;
3300	+	}
3301	+
3302	+	public ConcurrentHashMapSpliterator<K> trySplit() {
3303	+	int i, f, h;
3304	+	return (h = ((i = baseIndex) + (f = baseLimit)) >>> 1) <= i ? null :
3305	+	new KeySpliterator<K,V>(tab, baseSize, baseLimit = h,
3306	+	f, est >>>= 1);
3307	+	}
3308	+
3309	+	public void forEachRemaining(Action<? super K> action) {
3310	+	if (action == null) throw new NullPointerException();
3311	+	for (Node<K,V> p; (p = advance()) != null;)
3312	+	action.apply(p.key);
3313	+	}
3314	+
3315	+	public boolean tryAdvance(Action<? super K> action) {
3316	+	if (action == null) throw new NullPointerException();
3317	+	Node<K,V> p;
3318	+	if ((p = advance()) == null)
3319	+	return false;
3320	+	action.apply(p.key);
3321	+	return true;
3322	+	}
3323	+
3324	+	public long estimateSize() { return est; }
3325	+
3326	+	}
3327	+
3328	+	static final class ValueSpliterator<K,V> extends Traverser<K,V>
3329	+	implements ConcurrentHashMapSpliterator<V> {
3330	+	long est;               // size estimate
3331	+	ValueSpliterator(Node<K,V>[] tab, int size, int index, int limit,
3332	+	long est) {
3333	+	super(tab, size, index, limit);
3334	+	this.est = est;
3335	+	}
3336	+
3337	+	public ConcurrentHashMapSpliterator<V> trySplit() {
3338	+	int i, f, h;
3339	+	return (h = ((i = baseIndex) + (f = baseLimit)) >>> 1) <= i ? null :
3340	+	new ValueSpliterator<K,V>(tab, baseSize, baseLimit = h,
3341	+	f, est >>>= 1);
3342	+	}
3343	+
3344	+	public void forEachRemaining(Action<? super V> action) {
3345	+	if (action == null) throw new NullPointerException();
3346	+	for (Node<K,V> p; (p = advance()) != null;)
3347	+	action.apply(p.val);
3348	+	}
3349	+
3350	+	public boolean tryAdvance(Action<? super V> action) {
3351	+	if (action == null) throw new NullPointerException();
3352	+	Node<K,V> p;
3353	+	if ((p = advance()) == null)
3354	+	return false;
3355	+	action.apply(p.val);
3356	+	return true;
3357	+	}
3358	+
3359	+	public long estimateSize() { return est; }
3360	+
3361	+	}
3362	+
3363	+	static final class EntrySpliterator<K,V> extends Traverser<K,V>
3364	+	implements ConcurrentHashMapSpliterator<Map.Entry<K,V>> {
3365	+	final ConcurrentHashMapV8<K,V> map; // To export MapEntry
3366	+	long est;               // size estimate
3367	+	EntrySpliterator(Node<K,V>[] tab, int size, int index, int limit,
3368	+	long est, ConcurrentHashMapV8<K,V> map) {
3369	+	super(tab, size, index, limit);
3370	+	this.map = map;
3371	+	this.est = est;
3372	+	}
3373	+
3374	+	public ConcurrentHashMapSpliterator<Map.Entry<K,V>> trySplit() {
3375	+	int i, f, h;
3376	+	return (h = ((i = baseIndex) + (f = baseLimit)) >>> 1) <= i ? null :
3377	+	new EntrySpliterator<K,V>(tab, baseSize, baseLimit = h,
3378	+	f, est >>>= 1, map);
3379	+	}
3380	+
3381	+	public void forEachRemaining(Action<? super Map.Entry<K,V>> action) {
3382	+	if (action == null) throw new NullPointerException();
3383	+	for (Node<K,V> p; (p = advance()) != null; )
3384	+	action.apply(new MapEntry<K,V>(p.key, p.val, map));
3385	+	}
3386	+
3387	+	public boolean tryAdvance(Action<? super Map.Entry<K,V>> action) {
3388	+	if (action == null) throw new NullPointerException();
3389	+	Node<K,V> p;
3390	+	if ((p = advance()) == null)
3391	+	return false;
3392	+	action.apply(new MapEntry<K,V>(p.key, p.val, map));
3393	+	return true;
3394	+	}
3395	+
3396	+	public long estimateSize() { return est; }
3397	+
3398	+	}
3399	+
3400	+	// Parallel bulk operations
3401	+
3402		/**
3403	<	* Creates a new, empty map with a default initial capacity (16),
3404	<	* load factor (0.75) and concurrencyLevel (16).
3403	>	* Computes initial batch value for bulk tasks. The returned value
3404	>	* is approximately exp2 of the number of times (minus one) to
3405	>	* split task by two before executing leaf action. This value is
3406	>	* faster to compute and more convenient to use as a guide to
3407	>	* splitting than is the depth, since it is used while dividing by
3408	>	* two anyway.
3409		*/
3410	<	public ConcurrentHashMapV8() {
3411	<	this(DEFAULT_CAPACITY, DEFAULT_LOAD_FACTOR, DEFAULT_CONCURRENCY_LEVEL);
3410	>	final int batchFor(long b) {
3411	>	long n;
3412	>	if (b == Long.MAX_VALUE || (n = sumCount()) <= 1L || n < b)
3413	>	return 0;
3414	>	int sp = ForkJoinPool.getCommonPoolParallelism() << 2; // slack of 4
3415	>	return (b <= 0L || (n /= b) >= sp) ? sp : (int)n;
3416		}
3417
3418		/**
3419	<	* Creates a new map with the same mappings as the given map.
954	<	* The map is created with a capacity of 1.5 times the number
955	<	* of mappings in the given map or 16 (whichever is greater),
956	<	* and a default load factor (0.75) and concurrencyLevel (16).
3419	>	* Performs the given action for each (key, value).
3420		*
3421	<	* @param m the map
3421	>	* @param parallelismThreshold the (estimated) number of elements
3422	>	* needed for this operation to be executed in parallel
3423	>	* @param action the action
3424	>	* @since 1.8
3425		*/
3426	<	public ConcurrentHashMapV8(Map<? extends K, ? extends V> m) {
3427	<	this(DEFAULT_CAPACITY, DEFAULT_LOAD_FACTOR, DEFAULT_CONCURRENCY_LEVEL);
3428	<	if (m == null)
3429	<	throw new NullPointerException();
3430	<	internalPutAll(m);
3426	>	public void forEach(long parallelismThreshold,
3427	>	BiAction<? super K,? super V> action) {
3428	>	if (action == null) throw new NullPointerException();
3429	>	new ForEachMappingTask<K,V>
3430	>	(null, batchFor(parallelismThreshold), 0, 0, table,
3431	>	action).invoke();
3432		}
3433
3434		/**
3435	<	* Returns {@code true} if this map contains no key-value mappings.
3435	>	* Performs the given action for each non-null transformation
3436	>	* of each (key, value).
3437		*
3438	<	* @return {@code true} if this map contains no key-value mappings
3438	>	* @param parallelismThreshold the (estimated) number of elements
3439	>	* needed for this operation to be executed in parallel
3440	>	* @param transformer a function returning the transformation
3441	>	* for an element, or null if there is no transformation (in
3442	>	* which case the action is not applied)
3443	>	* @param action the action
3444	>	* @since 1.8
3445		*/
3446	<	public boolean isEmpty() {
3447	<	return counter.sum() <= 0L; // ignore transient negative values
3446	>	public <U> void forEach(long parallelismThreshold,
3447	>	BiFun<? super K, ? super V, ? extends U> transformer,
3448	>	Action<? super U> action) {
3449	>	if (transformer == null || action == null)
3450	>	throw new NullPointerException();
3451	>	new ForEachTransformedMappingTask<K,V,U>
3452	>	(null, batchFor(parallelismThreshold), 0, 0, table,
3453	>	transformer, action).invoke();
3454		}
3455
3456		/**
3457	<	* Returns the number of key-value mappings in this map.  If the
3458	<	* map contains more than {@code Integer.MAX_VALUE} elements, returns
3459	<	* {@code Integer.MAX_VALUE}.
3460	<	*
3461	<	* @return the number of key-value mappings in this map
3462	<	*/
3463	<	public int size() {
3464	<	long n = counter.sum();
3465	<	return ((n >>> 31) == 0) ? (int)n : (n < 0L) ? 0 : Integer.MAX_VALUE;
3457	>	* Returns a non-null result from applying the given search
3458	>	* function on each (key, value), or null if none.  Upon
3459	>	* success, further element processing is suppressed and the
3460	>	* results of any other parallel invocations of the search
3461	>	* function are ignored.
3462	>	*
3463	>	* @param parallelismThreshold the (estimated) number of elements
3464	>	* needed for this operation to be executed in parallel
3465	>	* @param searchFunction a function returning a non-null
3466	>	* result on success, else null
3467	>	* @return a non-null result from applying the given search
3468	>	* function on each (key, value), or null if none
3469	>	* @since 1.8
3470	>	*/
3471	>	public <U> U search(long parallelismThreshold,
3472	>	BiFun<? super K, ? super V, ? extends U> searchFunction) {
3473	>	if (searchFunction == null) throw new NullPointerException();
3474	>	return new SearchMappingsTask<K,V,U>
3475	>	(null, batchFor(parallelismThreshold), 0, 0, table,
3476	>	searchFunction, new AtomicReference<U>()).invoke();
3477		}
3478
3479		/**
3480	<	* Returns the value to which the specified key is mapped,
3481	<	* or {@code null} if this map contains no mapping for the key.
3482	<	*
3483	<	* <p>More formally, if this map contains a mapping from a key
3484	<	* {@code k} to a value {@code v} such that {@code key.equals(k)},
3485	<	* then this method returns {@code v}; otherwise it returns
3486	<	* {@code null}.  (There can be at most one such mapping.)
3487	<	*
3488	<	* @throws NullPointerException if the specified key is null
3489	<	*/
3490	<	@SuppressWarnings("unchecked")
3491	<	public V get(Object key) {
3492	<	if (key == null)
3480	>	* Returns the result of accumulating the given transformation
3481	>	* of all (key, value) pairs using the given reducer to
3482	>	* combine values, or null if none.
3483	>	*
3484	>	* @param parallelismThreshold the (estimated) number of elements
3485	>	* needed for this operation to be executed in parallel
3486	>	* @param transformer a function returning the transformation
3487	>	* for an element, or null if there is no transformation (in
3488	>	* which case it is not combined)
3489	>	* @param reducer a commutative associative combining function
3490	>	* @return the result of accumulating the given transformation
3491	>	* of all (key, value) pairs
3492	>	* @since 1.8
3493	>	*/
3494	>	public <U> U reduce(long parallelismThreshold,
3495	>	BiFun<? super K, ? super V, ? extends U> transformer,
3496	>	BiFun<? super U, ? super U, ? extends U> reducer) {
3497	>	if (transformer == null || reducer == null)
3498		throw new NullPointerException();
3499	<	return (V)internalGet(key);
3499	>	return new MapReduceMappingsTask<K,V,U>
3500	>	(null, batchFor(parallelismThreshold), 0, 0, table,
3501	>	null, transformer, reducer).invoke();
3502		}
3503
3504		/**
3505	<	* Tests if the specified object is a key in this table.
3506	<	*
3507	<	* @param  key   possible key
3508	<	* @return {@code true} if and only if the specified object
3509	<	*         is a key in this table, as determined by the
3510	<	*         {@code equals} method; {@code false} otherwise.
3511	<	* @throws NullPointerException if the specified key is null
3512	<	*/
3513	<	public boolean containsKey(Object key) {
3514	<	if (key == null)
3505	>	* Returns the result of accumulating the given transformation
3506	>	* of all (key, value) pairs using the given reducer to
3507	>	* combine values, and the given basis as an identity value.
3508	>	*
3509	>	* @param parallelismThreshold the (estimated) number of elements
3510	>	* needed for this operation to be executed in parallel
3511	>	* @param transformer a function returning the transformation
3512	>	* for an element
3513	>	* @param basis the identity (initial default value) for the reduction
3514	>	* @param reducer a commutative associative combining function
3515	>	* @return the result of accumulating the given transformation
3516	>	* of all (key, value) pairs
3517	>	* @since 1.8
3518	>	*/
3519	>	public double reduceToDouble(long parallelismThreshold,
3520	>	ObjectByObjectToDouble<? super K, ? super V> transformer,
3521	>	double basis,
3522	>	DoubleByDoubleToDouble reducer) {
3523	>	if (transformer == null || reducer == null)
3524		throw new NullPointerException();
3525	<	return internalGet(key) != null;
3525	>	return new MapReduceMappingsToDoubleTask<K,V>
3526	>	(null, batchFor(parallelismThreshold), 0, 0, table,
3527	>	null, transformer, basis, reducer).invoke();
3528		}
3529
3530		/**
3531	<	* Returns {@code true} if this map maps one or more keys to the
3532	<	* specified value. Note: This method requires a full internal
3533	<	* traversal of the hash table, and so is much slower than
3534	<	* method {@code containsKey}.
3535	<	*
3536	<	* @param value value whose presence in this map is to be tested
3537	<	* @return {@code true} if this map maps one or more keys to the
3538	<	*         specified value
3539	<	* @throws NullPointerException if the specified value is null
3540	<	*/
3541	<	public boolean containsValue(Object value) {
3542	<	if (value == null)
3531	>	* Returns the result of accumulating the given transformation
3532	>	* of all (key, value) pairs using the given reducer to
3533	>	* combine values, and the given basis as an identity value.
3534	>	*
3535	>	* @param parallelismThreshold the (estimated) number of elements
3536	>	* needed for this operation to be executed in parallel
3537	>	* @param transformer a function returning the transformation
3538	>	* for an element
3539	>	* @param basis the identity (initial default value) for the reduction
3540	>	* @param reducer a commutative associative combining function
3541	>	* @return the result of accumulating the given transformation
3542	>	* of all (key, value) pairs
3543	>	* @since 1.8
3544	>	*/
3545	>	public long reduceToLong(long parallelismThreshold,
3546	>	ObjectByObjectToLong<? super K, ? super V> transformer,
3547	>	long basis,
3548	>	LongByLongToLong reducer) {
3549	>	if (transformer == null || reducer == null)
3550		throw new NullPointerException();
3551	<	return new HashIterator().containsVal(value);
3551	>	return new MapReduceMappingsToLongTask<K,V>
3552	>	(null, batchFor(parallelismThreshold), 0, 0, table,
3553	>	null, transformer, basis, reducer).invoke();
3554		}
3555
3556		/**
3557	<	* Legacy method testing if some key maps into the specified value
3558	<	* in this table.  This method is identical in functionality to
3559	<	* {@link #containsValue}, and exists solely to ensure
3560	<	* full compatibility with class {@link java.util.Hashtable},
3561	<	* which supported this method prior to introduction of the
3562	<	* Java Collections framework.
3563	<	*
3564	<	* @param  value a value to search for
3565	<	* @return {@code true} if and only if some key maps to the
3566	<	*         {@code value} argument in this table as
3567	<	*         determined by the {@code equals} method;
3568	<	*         {@code false} otherwise
3569	<	* @throws NullPointerException if the specified value is null
3570	<	*/
3571	<	public boolean contains(Object value) {
3572	<	return containsValue(value);
3557	>	* Returns the result of accumulating the given transformation
3558	>	* of all (key, value) pairs using the given reducer to
3559	>	* combine values, and the given basis as an identity value.
3560	>	*
3561	>	* @param parallelismThreshold the (estimated) number of elements
3562	>	* needed for this operation to be executed in parallel
3563	>	* @param transformer a function returning the transformation
3564	>	* for an element
3565	>	* @param basis the identity (initial default value) for the reduction
3566	>	* @param reducer a commutative associative combining function
3567	>	* @return the result of accumulating the given transformation
3568	>	* of all (key, value) pairs
3569	>	* @since 1.8
3570	>	*/
3571	>	public int reduceToInt(long parallelismThreshold,
3572	>	ObjectByObjectToInt<? super K, ? super V> transformer,
3573	>	int basis,
3574	>	IntByIntToInt reducer) {
3575	>	if (transformer == null || reducer == null)
3576	>	throw new NullPointerException();
3577	>	return new MapReduceMappingsToIntTask<K,V>
3578	>	(null, batchFor(parallelismThreshold), 0, 0, table,
3579	>	null, transformer, basis, reducer).invoke();
3580		}
3581
3582		/**
3583	<	* Maps the specified key to the specified value in this table.
1059	<	* Neither the key nor the value can be null.
3583	>	* Performs the given action for each key.
3584		*
3585	<	* <p> The value can be retrieved by calling the {@code get} method
3586	<	* with a key that is equal to the original key.
3587	<	*
3588	<	* @param key key with which the specified value is to be associated
1065	<	* @param value value to be associated with the specified key
1066	<	* @return the previous value associated with {@code key}, or
1067	<	*         {@code null} if there was no mapping for {@code key}
1068	<	* @throws NullPointerException if the specified key or value is null
3585	>	* @param parallelismThreshold the (estimated) number of elements
3586	>	* needed for this operation to be executed in parallel
3587	>	* @param action the action
3588	>	* @since 1.8
3589		*/
3590	<	@SuppressWarnings("unchecked")
3591	<	public V put(K key, V value) {
3592	<	if (key == null || value == null)
3593	<	throw new NullPointerException();
3594	<	return (V)internalPut(key, value, true);
3590	>	public void forEachKey(long parallelismThreshold,
3591	>	Action<? super K> action) {
3592	>	if (action == null) throw new NullPointerException();
3593	>	new ForEachKeyTask<K,V>
3594	>	(null, batchFor(parallelismThreshold), 0, 0, table,
3595	>	action).invoke();
3596		}
3597
3598		/**
3599	<	* {@inheritDoc}
3599	>	* Performs the given action for each non-null transformation
3600	>	* of each key.
3601		*
3602	<	* @return the previous value associated with the specified key,
3603	<	*         or {@code null} if there was no mapping for the key
3604	<	* @throws NullPointerException if the specified key or value is null
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 the action is not applied)
3607	>	* @param action the action
3608	>	* @since 1.8
3609		*/
3610	<	@SuppressWarnings("unchecked")
3611	<	public V putIfAbsent(K key, V value) {
3612	<	if (key == null || value == null)
3610	>	public <U> void forEachKey(long parallelismThreshold,
3611	>	Fun<? super K, ? extends U> transformer,
3612	>	Action<? super U> action) {
3613	>	if (transformer == null || action == null)
3614		throw new NullPointerException();
3615	<	return (V)internalPut(key, value, false);
3615	>	new ForEachTransformedKeyTask<K,V,U>
3616	>	(null, batchFor(parallelismThreshold), 0, 0, table,
3617	>	transformer, action).invoke();
3618	>	}
3619	>
3620	>	/**
3621	>	* Returns a non-null result from applying the given search
3622	>	* function on each key, or null if none. Upon success,
3623	>	* further element processing is suppressed and the results of
3624	>	* any other parallel invocations of the search function are
3625	>	* ignored.
3626	>	*
3627	>	* @param parallelismThreshold the (estimated) number of elements
3628	>	* needed for this operation to be executed in parallel
3629	>	* @param searchFunction a function returning a non-null
3630	>	* result on success, else null
3631	>	* @return a non-null result from applying the given search
3632	>	* function on each key, or null if none
3633	>	* @since 1.8
3634	>	*/
3635	>	public <U> U searchKeys(long parallelismThreshold,
3636	>	Fun<? super K, ? extends U> searchFunction) {
3637	>	if (searchFunction == null) throw new NullPointerException();
3638	>	return new SearchKeysTask<K,V,U>
3639	>	(null, batchFor(parallelismThreshold), 0, 0, table,
3640	>	searchFunction, new AtomicReference<U>()).invoke();
3641	>	}
3642	>
3643	>	/**
3644	>	* Returns the result of accumulating all keys using the given
3645	>	* reducer to combine values, or null if none.
3646	>	*
3647	>	* @param parallelismThreshold the (estimated) number of elements
3648	>	* needed for this operation to be executed in parallel
3649	>	* @param reducer a commutative associative combining function
3650	>	* @return the result of accumulating all keys using the given
3651	>	* reducer to combine values, or null if none
3652	>	* @since 1.8
3653	>	*/
3654	>	public K reduceKeys(long parallelismThreshold,
3655	>	BiFun<? super K, ? super K, ? extends K> reducer) {
3656	>	if (reducer == null) throw new NullPointerException();
3657	>	return new ReduceKeysTask<K,V>
3658	>	(null, batchFor(parallelismThreshold), 0, 0, table,
3659	>	null, reducer).invoke();
3660	>	}
3661	>
3662	>	/**
3663	>	* Returns the result of accumulating the given transformation
3664	>	* of all keys using the given reducer to combine values, or
3665	>	* null if none.
3666	>	*
3667	>	* @param parallelismThreshold the (estimated) number of elements
3668	>	* needed for this operation to be executed in parallel
3669	>	* @param transformer a function returning the transformation
3670	>	* for an element, or null if there is no transformation (in
3671	>	* which case it is not combined)
3672	>	* @param reducer a commutative associative combining function
3673	>	* @return the result of accumulating the given transformation
3674	>	* of all keys
3675	>	* @since 1.8
3676	>	*/
3677	>	public <U> U reduceKeys(long parallelismThreshold,
3678	>	Fun<? super K, ? extends U> transformer,
3679	>	BiFun<? super U, ? super U, ? extends U> reducer) {
3680	>	if (transformer == null || reducer == null)
3681	>	throw new NullPointerException();
3682	>	return new MapReduceKeysTask<K,V,U>
3683	>	(null, batchFor(parallelismThreshold), 0, 0, table,
3684	>	null, transformer, reducer).invoke();
3685		}
3686
3687		/**
3688	<	* Copies all of the mappings from the specified map to this one.
3689	<	* These mappings replace any mappings that this map had for any of the
3690	<	* keys currently in the specified map.
3691	<	*
3692	<	* @param m mappings to be stored in this map
3693	<	*/
3694	<	public void putAll(Map<? extends K, ? extends V> m) {
3695	<	if (m == null)
3688	>	* Returns the result of accumulating the given transformation
3689	>	* of all keys using the given reducer to combine values, and
3690	>	* the given basis as an identity value.
3691	>	*
3692	>	* @param parallelismThreshold the (estimated) number of elements
3693	>	* needed for this operation to be executed in parallel
3694	>	* @param transformer a function returning the transformation
3695	>	* for an element
3696	>	* @param basis the identity (initial default value) for the reduction
3697	>	* @param reducer a commutative associative combining function
3698	>	* @return the result of accumulating the given transformation
3699	>	* of all keys
3700	>	* @since 1.8
3701	>	*/
3702	>	public double reduceKeysToDouble(long parallelismThreshold,
3703	>	ObjectToDouble<? super K> transformer,
3704	>	double basis,
3705	>	DoubleByDoubleToDouble reducer) {
3706	>	if (transformer == null || reducer == null)
3707		throw new NullPointerException();
3708	<	internalPutAll(m);
3708	>	return new MapReduceKeysToDoubleTask<K,V>
3709	>	(null, batchFor(parallelismThreshold), 0, 0, table,
3710	>	null, transformer, basis, reducer).invoke();
3711		}
3712
3713		/**
3714	<	* If the specified key is not already associated with a value,
3715	<	* computes its value using the given mappingFunction, and if
3716	<	* non-null, enters it into the map.  This is equivalent to
3717	<	*  <pre> {@code
3718	<	* if (map.containsKey(key))
3719	<	*   return map.get(key);
3720	<	* value = mappingFunction.map(key);
3721	<	* if (value != null)
3722	<	*   map.put(key, value);
3723	<	* return value;}</pre>
3724	<	*
3725	<	* except that the action is performed atomically.  Some attempted
3726	<	* update operations on this map by other threads may be blocked
3727	<	* while computation is in progress, so the computation should be
3728	<	* short and simple, and must not attempt to update any other
3729	<	* mappings of this Map. The most appropriate usage is to
3730	<	* construct a new object serving as an initial mapped value, or
3731	<	* memoized result, as in:
3732	<	*  <pre> {@code
1124	<	* map.computeIfAbsent(key, new MappingFunction<K, V>() {
1125	<	*   public V map(K k) { return new Value(f(k)); }});}</pre>
1126	<	*
1127	<	* @param key key with which the specified value is to be associated
1128	<	* @param mappingFunction the function to compute a value
1129	<	* @return the current (existing or computed) value associated with
1130	<	*         the specified key, or {@code null} if the computation
1131	<	*         returned {@code null}.
1132	<	* @throws NullPointerException if the specified key or mappingFunction
1133	<	*         is null,
1134	<	* @throws IllegalStateException if the computation detectably
1135	<	*         attempts a recursive update to this map that would
1136	<	*         otherwise never complete.
1137	<	* @throws RuntimeException or Error if the mappingFunction does so,
1138	<	*         in which case the mapping is left unestablished.
1139	<	*/
1140	<	public V computeIfAbsent(K key, MappingFunction<? super K, ? extends V> mappingFunction) {
1141	<	if (key == null || mappingFunction == null)
3714	>	* Returns the result of accumulating the given transformation
3715	>	* of all keys using the given reducer to combine values, and
3716	>	* the given basis as an identity value.
3717	>	*
3718	>	* @param parallelismThreshold the (estimated) number of elements
3719	>	* needed for this operation to be executed in parallel
3720	>	* @param transformer a function returning the transformation
3721	>	* for an element
3722	>	* @param basis the identity (initial default value) for the reduction
3723	>	* @param reducer a commutative associative combining function
3724	>	* @return the result of accumulating the given transformation
3725	>	* of all keys
3726	>	* @since 1.8
3727	>	*/
3728	>	public long reduceKeysToLong(long parallelismThreshold,
3729	>	ObjectToLong<? super K> transformer,
3730	>	long basis,
3731	>	LongByLongToLong reducer) {
3732	>	if (transformer == null || reducer == null)
3733		throw new NullPointerException();
3734	<	return internalCompute(key, mappingFunction, false);
3734	>	return new MapReduceKeysToLongTask<K,V>
3735	>	(null, batchFor(parallelismThreshold), 0, 0, table,
3736	>	null, transformer, basis, reducer).invoke();
3737		}
3738
3739		/**
3740	<	* Computes the value associated with the given key using the given
3741	<	* mappingFunction, and if non-null, enters it into the map.  This
3742	<	* is equivalent to
3743	<	*  <pre> {@code
3744	<	* value = mappingFunction.map(key);
3745	<	* if (value != null)
3746	<	*   map.put(key, value);
3747	<	* else
3748	<	*   value = map.get(key);
3749	<	* return value;}</pre>
3750	<	*
3751	<	* except that the action is performed atomically.  Some attempted
3752	<	* update operations on this map by other threads may be blocked
3753	<	* while computation is in progress, so the computation should be
3754	<	* short and simple, and must not attempt to update any other
3755	<	* mappings of this Map.
3756	<	*
3757	<	* @param key key with which the specified value is to be associated
3758	<	* @param mappingFunction the function to compute a value
1166	<	* @return the current value associated with
1167	<	*         the specified key, or {@code null} if the computation
1168	<	*         returned {@code null} and the value was not otherwise present.
1169	<	* @throws NullPointerException if the specified key or mappingFunction
1170	<	*         is null,
1171	<	* @throws IllegalStateException if the computation detectably
1172	<	*         attempts a recursive update to this map that would
1173	<	*         otherwise never complete.
1174	<	* @throws RuntimeException or Error if the mappingFunction does so,
1175	<	*         in which case the mapping is unchanged.
1176	<	*/
1177	<	public V compute(K key, MappingFunction<? super K, ? extends V> mappingFunction) {
1178	<	if (key == null || mappingFunction == null)
3740	>	* Returns the result of accumulating the given transformation
3741	>	* of all keys using the given reducer to combine values, and
3742	>	* the given basis as an identity value.
3743	>	*
3744	>	* @param parallelismThreshold the (estimated) number of elements
3745	>	* needed for this operation to be executed in parallel
3746	>	* @param transformer a function returning the transformation
3747	>	* for an element
3748	>	* @param basis the identity (initial default value) for the reduction
3749	>	* @param reducer a commutative associative combining function
3750	>	* @return the result of accumulating the given transformation
3751	>	* of all keys
3752	>	* @since 1.8
3753	>	*/
3754	>	public int reduceKeysToInt(long parallelismThreshold,
3755	>	ObjectToInt<? super K> transformer,
3756	>	int basis,
3757	>	IntByIntToInt reducer) {
3758	>	if (transformer == null || reducer == null)
3759		throw new NullPointerException();
3760	<	return internalCompute(key, mappingFunction, true);
3760	>	return new MapReduceKeysToIntTask<K,V>
3761	>	(null, batchFor(parallelismThreshold), 0, 0, table,
3762	>	null, transformer, basis, reducer).invoke();
3763		}
3764
3765		/**
3766	<	* Removes the key (and its corresponding value) from this map.
1185	<	* This method does nothing if the key is not in the map.
3766	>	* Performs the given action for each value.
3767		*
3768	<	* @param  key the key that needs to be removed
3769	<	* @return the previous value associated with {@code key}, or
3770	<	*         {@code null} if there was no mapping for {@code key}
3771	<	* @throws NullPointerException if the specified key is null
3768	>	* @param parallelismThreshold the (estimated) number of elements
3769	>	* needed for this operation to be executed in parallel
3770	>	* @param action the action
3771	>	* @since 1.8
3772		*/
3773	<	@SuppressWarnings("unchecked")
3774	<	public V remove(Object key) {
3775	<	if (key == null)
3773	>	public void forEachValue(long parallelismThreshold,
3774	>	Action<? super V> action) {
3775	>	if (action == null)
3776		throw new NullPointerException();
3777	<	return (V)internalReplace(key, null, null);
3777	>	new ForEachValueTask<K,V>
3778	>	(null, batchFor(parallelismThreshold), 0, 0, table,
3779	>	action).invoke();
3780		}
3781
3782		/**
3783	<	* {@inheritDoc}
3784	<	*
3785	<	* @throws NullPointerException if the specified key is null
3786	<	*/
3787	<	public boolean remove(Object key, Object value) {
3788	<	if (key == null)
3783	>	* Performs the given action for each non-null transformation
3784	>	* of each value.
3785	>	*
3786	>	* @param parallelismThreshold the (estimated) number of elements
3787	>	* needed for this operation to be executed in parallel
3788	>	* @param transformer a function returning the transformation
3789	>	* for an element, or null if there is no transformation (in
3790	>	* which case the action is not applied)
3791	>	* @param action the action
3792	>	* @since 1.8
3793	>	*/
3794	>	public <U> void forEachValue(long parallelismThreshold,
3795	>	Fun<? super V, ? extends U> transformer,
3796	>	Action<? super U> action) {
3797	>	if (transformer == null || action == null)
3798		throw new NullPointerException();
3799	<	if (value == null)
3800	<	return false;
3801	<	return internalReplace(key, null, value) != null;
3799	>	new ForEachTransformedValueTask<K,V,U>
3800	>	(null, batchFor(parallelismThreshold), 0, 0, table,
3801	>	transformer, action).invoke();
3802	>	}
3803	>
3804	>	/**
3805	>	* Returns a non-null result from applying the given search
3806	>	* function on each value, or null if none.  Upon success,
3807	>	* further element processing is suppressed and the results of
3808	>	* any other parallel invocations of the search function are
3809	>	* ignored.
3810	>	*
3811	>	* @param parallelismThreshold the (estimated) number of elements
3812	>	* needed for this operation to be executed in parallel
3813	>	* @param searchFunction a function returning a non-null
3814	>	* result on success, else null
3815	>	* @return a non-null result from applying the given search
3816	>	* function on each value, or null if none
3817	>	* @since 1.8
3818	>	*/
3819	>	public <U> U searchValues(long parallelismThreshold,
3820	>	Fun<? super V, ? extends U> searchFunction) {
3821	>	if (searchFunction == null) throw new NullPointerException();
3822	>	return new SearchValuesTask<K,V,U>
3823	>	(null, batchFor(parallelismThreshold), 0, 0, table,
3824	>	searchFunction, new AtomicReference<U>()).invoke();
3825	>	}
3826	>
3827	>	/**
3828	>	* Returns the result of accumulating all values using the
3829	>	* given reducer to combine values, or null if none.
3830	>	*
3831	>	* @param parallelismThreshold the (estimated) number of elements
3832	>	* needed for this operation to be executed in parallel
3833	>	* @param reducer a commutative associative combining function
3834	>	* @return the result of accumulating all values
3835	>	* @since 1.8
3836	>	*/
3837	>	public V reduceValues(long parallelismThreshold,
3838	>	BiFun<? super V, ? super V, ? extends V> reducer) {
3839	>	if (reducer == null) throw new NullPointerException();
3840	>	return new ReduceValuesTask<K,V>
3841	>	(null, batchFor(parallelismThreshold), 0, 0, table,
3842	>	null, reducer).invoke();
3843	>	}
3844	>
3845	>	/**
3846	>	* Returns the result of accumulating the given transformation
3847	>	* of all values using the given reducer to combine values, or
3848	>	* null if none.
3849	>	*
3850	>	* @param parallelismThreshold the (estimated) number of elements
3851	>	* needed for this operation to be executed in parallel
3852	>	* @param transformer a function returning the transformation
3853	>	* for an element, or null if there is no transformation (in
3854	>	* which case it is not combined)
3855	>	* @param reducer a commutative associative combining function
3856	>	* @return the result of accumulating the given transformation
3857	>	* of all values
3858	>	* @since 1.8
3859	>	*/
3860	>	public <U> U reduceValues(long parallelismThreshold,
3861	>	Fun<? super V, ? extends U> transformer,
3862	>	BiFun<? super U, ? super U, ? extends U> reducer) {
3863	>	if (transformer == null || reducer == null)
3864	>	throw new NullPointerException();
3865	>	return new MapReduceValuesTask<K,V,U>
3866	>	(null, batchFor(parallelismThreshold), 0, 0, table,
3867	>	null, transformer, reducer).invoke();
3868		}
3869
3870		/**
3871	<	* {@inheritDoc}
3872	<	*
3873	<	* @throws NullPointerException if any of the arguments are null
3874	<	*/
3875	<	public boolean replace(K key, V oldValue, V newValue) {
3876	<	if (key == null || oldValue == null || newValue == null)
3871	>	* Returns the result of accumulating the given transformation
3872	>	* of all values using the given reducer to combine values,
3873	>	* and the given basis as an identity value.
3874	>	*
3875	>	* @param parallelismThreshold the (estimated) number of elements
3876	>	* needed for this operation to be executed in parallel
3877	>	* @param transformer a function returning the transformation
3878	>	* for an element
3879	>	* @param basis the identity (initial default value) for the reduction
3880	>	* @param reducer a commutative associative combining function
3881	>	* @return the result of accumulating the given transformation
3882	>	* of all values
3883	>	* @since 1.8
3884	>	*/
3885	>	public double reduceValuesToDouble(long parallelismThreshold,
3886	>	ObjectToDouble<? super V> transformer,
3887	>	double basis,
3888	>	DoubleByDoubleToDouble reducer) {
3889	>	if (transformer == null || reducer == null)
3890		throw new NullPointerException();
3891	<	return internalReplace(key, newValue, oldValue) != null;
3891	>	return new MapReduceValuesToDoubleTask<K,V>
3892	>	(null, batchFor(parallelismThreshold), 0, 0, table,
3893	>	null, transformer, basis, reducer).invoke();
3894		}
3895
3896		/**
3897	<	* {@inheritDoc}
3898	<	*
3899	<	* @return the previous value associated with the specified key,
3900	<	*         or {@code null} if there was no mapping for the key
3901	<	* @throws NullPointerException if the specified key or value is null
3902	<	*/
3903	<	@SuppressWarnings("unchecked")
3904	<	public V replace(K key, V value) {
3905	<	if (key == null || value == null)
3897	>	* Returns the result of accumulating the given transformation
3898	>	* of all values using the given reducer to combine values,
3899	>	* and the given basis as an identity value.
3900	>	*
3901	>	* @param parallelismThreshold the (estimated) number of elements
3902	>	* needed for this operation to be executed in parallel
3903	>	* @param transformer a function returning the transformation
3904	>	* for an element
3905	>	* @param basis the identity (initial default value) for the reduction
3906	>	* @param reducer a commutative associative combining function
3907	>	* @return the result of accumulating the given transformation
3908	>	* of all values
3909	>	* @since 1.8
3910	>	*/
3911	>	public long reduceValuesToLong(long parallelismThreshold,
3912	>	ObjectToLong<? super V> transformer,
3913	>	long basis,
3914	>	LongByLongToLong reducer) {
3915	>	if (transformer == null || reducer == null)
3916		throw new NullPointerException();
3917	<	return (V)internalReplace(key, value, null);
3917	>	return new MapReduceValuesToLongTask<K,V>
3918	>	(null, batchFor(parallelismThreshold), 0, 0, table,
3919	>	null, transformer, basis, reducer).invoke();
3920		}
3921
3922		/**
3923	<	* Removes all of the mappings from this map.
3924	<	*/
3925	<	public void clear() {
3926	<	internalClear();
3923	>	* Returns the result of accumulating the given transformation
3924	>	* of all values using the given reducer to combine values,
3925	>	* and the given basis as an identity value.
3926	>	*
3927	>	* @param parallelismThreshold the (estimated) number of elements
3928	>	* needed for this operation to be executed in parallel
3929	>	* @param transformer a function returning the transformation
3930	>	* for an element
3931	>	* @param basis the identity (initial default value) for the reduction
3932	>	* @param reducer a commutative associative combining function
3933	>	* @return the result of accumulating the given transformation
3934	>	* of all values
3935	>	* @since 1.8
3936	>	*/
3937	>	public int reduceValuesToInt(long parallelismThreshold,
3938	>	ObjectToInt<? super V> transformer,
3939	>	int basis,
3940	>	IntByIntToInt reducer) {
3941	>	if (transformer == null || reducer == null)
3942	>	throw new NullPointerException();
3943	>	return new MapReduceValuesToIntTask<K,V>
3944	>	(null, batchFor(parallelismThreshold), 0, 0, table,
3945	>	null, transformer, basis, reducer).invoke();
3946		}
3947
3948		/**
3949	<	* Returns a {@link Set} view of the keys contained in this map.
1246	<	* The set is backed by the map, so changes to the map are
1247	<	* reflected in the set, and vice-versa.  The set supports element
1248	<	* removal, which removes the corresponding mapping from this map,
1249	<	* via the {@code Iterator.remove}, {@code Set.remove},
1250	<	* {@code removeAll}, {@code retainAll}, and {@code clear}
1251	<	* operations.  It does not support the {@code add} or
1252	<	* {@code addAll} operations.
3949	>	* Performs the given action for each entry.
3950		*
3951	<	* <p>The view's {@code iterator} is a "weakly consistent" iterator
3952	<	* that will never throw {@link ConcurrentModificationException},
3953	<	* and guarantees to traverse elements as they existed upon
3954	<	* construction of the iterator, and may (but is not guaranteed to)
1258	<	* reflect any modifications subsequent to construction.
3951	>	* @param parallelismThreshold the (estimated) number of elements
3952	>	* needed for this operation to be executed in parallel
3953	>	* @param action the action
3954	>	* @since 1.8
3955		*/
3956	<	public Set<K> keySet() {
3957	<	Set<K> ks = keySet;
3958	<	return (ks != null) ? ks : (keySet = new KeySet());
3956	>	public void forEachEntry(long parallelismThreshold,
3957	>	Action<? super Map.Entry<K,V>> action) {
3958	>	if (action == null) throw new NullPointerException();
3959	>	new ForEachEntryTask<K,V>(null, batchFor(parallelismThreshold), 0, 0, table,
3960	>	action).invoke();
3961		}
3962
3963		/**
3964	<	* Returns a {@link Collection} view of the values contained in this map.
3965	<	* The collection is backed by the map, so changes to the map are
1268	<	* reflected in the collection, and vice-versa.  The collection
1269	<	* supports element removal, which removes the corresponding
1270	<	* mapping from this map, via the {@code Iterator.remove},
1271	<	* {@code Collection.remove}, {@code removeAll},
1272	<	* {@code retainAll}, and {@code clear} operations.  It does not
1273	<	* support the {@code add} or {@code addAll} operations.
3964	>	* Performs the given action for each non-null transformation
3965	>	* of each entry.
3966		*
3967	<	* <p>The view's {@code iterator} is a "weakly consistent" iterator
3968	<	* that will never throw {@link ConcurrentModificationException},
3969	<	* and guarantees to traverse elements as they existed upon
3970	<	* construction of the iterator, and may (but is not guaranteed to)
3971	<	* reflect any modifications subsequent to construction.
3967	>	* @param parallelismThreshold the (estimated) number of elements
3968	>	* needed for this operation to be executed in parallel
3969	>	* @param transformer a function returning the transformation
3970	>	* for an element, or null if there is no transformation (in
3971	>	* which case the action is not applied)
3972	>	* @param action the action
3973	>	* @since 1.8
3974		*/
3975	<	public Collection<V> values() {
3976	<	Collection<V> vs = values;
3977	<	return (vs != null) ? vs : (values = new Values());
3975	>	public <U> void forEachEntry(long parallelismThreshold,
3976	>	Fun<Map.Entry<K,V>, ? extends U> transformer,
3977	>	Action<? super U> action) {
3978	>	if (transformer == null || action == null)
3979	>	throw new NullPointerException();
3980	>	new ForEachTransformedEntryTask<K,V,U>
3981	>	(null, batchFor(parallelismThreshold), 0, 0, table,
3982	>	transformer, action).invoke();
3983	>	}
3984	>
3985	>	/**
3986	>	* Returns a non-null result from applying the given search
3987	>	* function on each entry, or null if none.  Upon success,
3988	>	* further element processing is suppressed and the results of
3989	>	* any other parallel invocations of the search function are
3990	>	* ignored.
3991	>	*
3992	>	* @param parallelismThreshold the (estimated) number of elements
3993	>	* needed for this operation to be executed in parallel
3994	>	* @param searchFunction a function returning a non-null
3995	>	* result on success, else null
3996	>	* @return a non-null result from applying the given search
3997	>	* function on each entry, or null if none
3998	>	* @since 1.8
3999	>	*/
4000	>	public <U> U searchEntries(long parallelismThreshold,
4001	>	Fun<Map.Entry<K,V>, ? extends U> searchFunction) {
4002	>	if (searchFunction == null) throw new NullPointerException();
4003	>	return new SearchEntriesTask<K,V,U>
4004	>	(null, batchFor(parallelismThreshold), 0, 0, table,
4005	>	searchFunction, new AtomicReference<U>()).invoke();
4006	>	}
4007	>
4008	>	/**
4009	>	* Returns the result of accumulating all entries using the
4010	>	* given reducer to combine values, or null if none.
4011	>	*
4012	>	* @param parallelismThreshold the (estimated) number of elements
4013	>	* needed for this operation to be executed in parallel
4014	>	* @param reducer a commutative associative combining function
4015	>	* @return the result of accumulating all entries
4016	>	* @since 1.8
4017	>	*/
4018	>	public Map.Entry<K,V> reduceEntries(long parallelismThreshold,
4019	>	BiFun<Map.Entry<K,V>, Map.Entry<K,V>, ? extends Map.Entry<K,V>> reducer) {
4020	>	if (reducer == null) throw new NullPointerException();
4021	>	return new ReduceEntriesTask<K,V>
4022	>	(null, batchFor(parallelismThreshold), 0, 0, table,
4023	>	null, reducer).invoke();
4024	>	}
4025	>
4026	>	/**
4027	>	* Returns the result of accumulating the given transformation
4028	>	* of all entries using the given reducer to combine values,
4029	>	* or null if none.
4030	>	*
4031	>	* @param parallelismThreshold the (estimated) number of elements
4032	>	* needed for this operation to be executed in parallel
4033	>	* @param transformer a function returning the transformation
4034	>	* for an element, or null if there is no transformation (in
4035	>	* which case it is not combined)
4036	>	* @param reducer a commutative associative combining function
4037	>	* @return the result of accumulating the given transformation
4038	>	* of all entries
4039	>	* @since 1.8
4040	>	*/
4041	>	public <U> U reduceEntries(long parallelismThreshold,
4042	>	Fun<Map.Entry<K,V>, ? extends U> transformer,
4043	>	BiFun<? super U, ? super U, ? extends U> reducer) {
4044	>	if (transformer == null || reducer == null)
4045	>	throw new NullPointerException();
4046	>	return new MapReduceEntriesTask<K,V,U>
4047	>	(null, batchFor(parallelismThreshold), 0, 0, table,
4048	>	null, transformer, reducer).invoke();
4049		}
4050
4051		/**
4052	<	* Returns a {@link Set} view of the mappings contained in this map.
4053	<	* The set is backed by the map, so changes to the map are
4054	<	* reflected in the set, and vice-versa.  The set supports element
4055	<	* removal, which removes the corresponding mapping from the map,
4056	<	* via the {@code Iterator.remove}, {@code Set.remove},
4057	<	* {@code removeAll}, {@code retainAll}, and {@code clear}
4058	<	* operations.  It does not support the {@code add} or
4059	<	* {@code addAll} operations.
4060	<	*
4061	<	* <p>The view's {@code iterator} is a "weakly consistent" iterator
4062	<	* that will never throw {@link ConcurrentModificationException},
4063	<	* and guarantees to traverse elements as they existed upon
4064	<	* construction of the iterator, and may (but is not guaranteed to)
4065	<	* reflect any modifications subsequent to construction.
4066	<	*/
4067	<	public Set<Map.Entry<K,V>> entrySet() {
4068	<	Set<Map.Entry<K,V>> es = entrySet;
4069	<	return (es != null) ? es : (entrySet = new EntrySet());
4052	>	* Returns the result of accumulating the given transformation
4053	>	* of all entries using the given reducer to combine values,
4054	>	* and the given basis as an identity value.
4055	>	*
4056	>	* @param parallelismThreshold the (estimated) number of elements
4057	>	* needed for this operation to be executed in parallel
4058	>	* @param transformer a function returning the transformation
4059	>	* for an element
4060	>	* @param basis the identity (initial default value) for the reduction
4061	>	* @param reducer a commutative associative combining function
4062	>	* @return the result of accumulating the given transformation
4063	>	* of all entries
4064	>	* @since 1.8
4065	>	*/
4066	>	public double reduceEntriesToDouble(long parallelismThreshold,
4067	>	ObjectToDouble<Map.Entry<K,V>> transformer,
4068	>	double basis,
4069	>	DoubleByDoubleToDouble reducer) {
4070	>	if (transformer == null || reducer == null)
4071	>	throw new NullPointerException();
4072	>	return new MapReduceEntriesToDoubleTask<K,V>
4073	>	(null, batchFor(parallelismThreshold), 0, 0, table,
4074	>	null, transformer, basis, reducer).invoke();
4075		}
4076
4077		/**
4078	<	* Returns an enumeration of the keys in this table.
4079	<	*
4080	<	* @return an enumeration of the keys in this table
4081	<	* @see #keySet()
4082	<	*/
4083	<	public Enumeration<K> keys() {
4084	<	return new KeyIterator();
4078	>	* Returns the result of accumulating the given transformation
4079	>	* of all entries using the given reducer to combine values,
4080	>	* and the given basis as an identity value.
4081	>	*
4082	>	* @param parallelismThreshold the (estimated) number of elements
4083	>	* needed for this operation to be executed in parallel
4084	>	* @param transformer a function returning the transformation
4085	>	* for an element
4086	>	* @param basis the identity (initial default value) for the reduction
4087	>	* @param reducer a commutative associative combining function
4088	>	* @return the result of accumulating the given transformation
4089	>	* of all entries
4090	>	* @since 1.8
4091	>	*/
4092	>	public long reduceEntriesToLong(long parallelismThreshold,
4093	>	ObjectToLong<Map.Entry<K,V>> transformer,
4094	>	long basis,
4095	>	LongByLongToLong reducer) {
4096	>	if (transformer == null || reducer == null)
4097	>	throw new NullPointerException();
4098	>	return new MapReduceEntriesToLongTask<K,V>
4099	>	(null, batchFor(parallelismThreshold), 0, 0, table,
4100	>	null, transformer, basis, reducer).invoke();
4101		}
4102
4103		/**
4104	<	* Returns an enumeration of the values in this table.
4105	<	*
4106	<	* @return an enumeration of the values in this table
4107	<	* @see #values()
4108	<	*/
4109	<	public Enumeration<V> elements() {
4110	<	return new ValueIterator();
4104	>	* Returns the result of accumulating the given transformation
4105	>	* of all entries using the given reducer to combine values,
4106	>	* and the given basis as an identity value.
4107	>	*
4108	>	* @param parallelismThreshold the (estimated) number of elements
4109	>	* needed for this operation to be executed in parallel
4110	>	* @param transformer a function returning the transformation
4111	>	* for an element
4112	>	* @param basis the identity (initial default value) for the reduction
4113	>	* @param reducer a commutative associative combining function
4114	>	* @return the result of accumulating the given transformation
4115	>	* of all entries
4116	>	* @since 1.8
4117	>	*/
4118	>	public int reduceEntriesToInt(long parallelismThreshold,
4119	>	ObjectToInt<Map.Entry<K,V>> transformer,
4120	>	int basis,
4121	>	IntByIntToInt reducer) {
4122	>	if (transformer == null || reducer == null)
4123	>	throw new NullPointerException();
4124	>	return new MapReduceEntriesToIntTask<K,V>
4125	>	(null, batchFor(parallelismThreshold), 0, 0, table,
4126	>	null, transformer, basis, reducer).invoke();
4127		}
4128
4129	+
4130	+	/* ----------------Views -------------- */
4131	+
4132		/**
4133	<	* Returns the hash code value for this {@link Map}, i.e.,
1329	<	* the sum of, for each key-value pair in the map,
1330	<	* {@code key.hashCode() ^ value.hashCode()}.
1331	<	*
1332	<	* @return the hash code value for this map
4133	>	* Base class for views.
4134		*/
4135	<	public int hashCode() {
4136	<	return new HashIterator().mapHashCode();
4135	>	abstract static class CollectionView<K,V,E>
4136	>	implements Collection<E>, java.io.Serializable {
4137	>	private static final long serialVersionUID = 7249069246763182397L;
4138	>	final ConcurrentHashMapV8<K,V> map;
4139	>	CollectionView(ConcurrentHashMapV8<K,V> map)  { this.map = map; }
4140	>
4141	>	/**
4142	>	* Returns the map backing this view.
4143	>	*
4144	>	* @return the map backing this view
4145	>	*/
4146	>	public ConcurrentHashMapV8<K,V> getMap() { return map; }
4147	>
4148	>	/**
4149	>	* Removes all of the elements from this view, by removing all
4150	>	* the mappings from the map backing this view.
4151	>	*/
4152	>	public final void clear()      { map.clear(); }
4153	>	public final int size()        { return map.size(); }
4154	>	public final boolean isEmpty() { return map.isEmpty(); }
4155	>
4156	>	// implementations below rely on concrete classes supplying these
4157	>	// abstract methods
4158	>	/**
4159	>	* Returns a "weakly consistent" iterator that will never
4160	>	* throw {@link ConcurrentModificationException}, and
4161	>	* guarantees to traverse elements as they existed upon
4162	>	* construction of the iterator, and may (but is not
4163	>	* guaranteed to) reflect any modifications subsequent to
4164	>	* construction.
4165	>	*/
4166	>	public abstract Iterator<E> iterator();
4167	>	public abstract boolean contains(Object o);
4168	>	public abstract boolean remove(Object o);
4169	>
4170	>	private static final String oomeMsg = "Required array size too large";
4171	>
4172	>	public final Object[] toArray() {
4173	>	long sz = map.mappingCount();
4174	>	if (sz > MAX_ARRAY_SIZE)
4175	>	throw new OutOfMemoryError(oomeMsg);
4176	>	int n = (int)sz;
4177	>	Object[] r = new Object[n];
4178	>	int i = 0;
4179	>	for (E e : this) {
4180	>	if (i == n) {
4181	>	if (n >= MAX_ARRAY_SIZE)
4182	>	throw new OutOfMemoryError(oomeMsg);
4183	>	if (n >= MAX_ARRAY_SIZE - (MAX_ARRAY_SIZE >>> 1) - 1)
4184	>	n = MAX_ARRAY_SIZE;
4185	>	else
4186	>	n += (n >>> 1) + 1;
4187	>	r = Arrays.copyOf(r, n);
4188	>	}
4189	>	r[i++] = e;
4190	>	}
4191	>	return (i == n) ? r : Arrays.copyOf(r, i);
4192	>	}
4193	>
4194	>	@SuppressWarnings("unchecked")
4195	>	public final <T> T[] toArray(T[] a) {
4196	>	long sz = map.mappingCount();
4197	>	if (sz > MAX_ARRAY_SIZE)
4198	>	throw new OutOfMemoryError(oomeMsg);
4199	>	int m = (int)sz;
4200	>	T[] r = (a.length >= m) ? a :
4201	>	(T[])java.lang.reflect.Array
4202	>	.newInstance(a.getClass().getComponentType(), m);
4203	>	int n = r.length;
4204	>	int i = 0;
4205	>	for (E e : this) {
4206	>	if (i == n) {
4207	>	if (n >= MAX_ARRAY_SIZE)
4208	>	throw new OutOfMemoryError(oomeMsg);
4209	>	if (n >= MAX_ARRAY_SIZE - (MAX_ARRAY_SIZE >>> 1) - 1)
4210	>	n = MAX_ARRAY_SIZE;
4211	>	else
4212	>	n += (n >>> 1) + 1;
4213	>	r = Arrays.copyOf(r, n);
4214	>	}
4215	>	r[i++] = (T)e;
4216	>	}
4217	>	if (a == r && i < n) {
4218	>	r[i] = null; // null-terminate
4219	>	return r;
4220	>	}
4221	>	return (i == n) ? r : Arrays.copyOf(r, i);
4222	>	}
4223	>
4224	>	/**
4225	>	* Returns a string representation of this collection.
4226	>	* The string representation consists of the string representations
4227	>	* of the collection's elements in the order they are returned by
4228	>	* its iterator, enclosed in square brackets ({@code "[]"}).
4229	>	* Adjacent elements are separated by the characters {@code ", "}
4230	>	* (comma and space).  Elements are converted to strings as by
4231	>	* {@link String#valueOf(Object)}.
4232	>	*
4233	>	* @return a string representation of this collection
4234	>	*/
4235	>	public final String toString() {
4236	>	StringBuilder sb = new StringBuilder();
4237	>	sb.append('[');
4238	>	Iterator<E> it = iterator();
4239	>	if (it.hasNext()) {
4240	>	for (;;) {
4241	>	Object e = it.next();
4242	>	sb.append(e == this ? "(this Collection)" : e);
4243	>	if (!it.hasNext())
4244	>	break;
4245	>	sb.append(',').append(' ');
4246	>	}
4247	>	}
4248	>	return sb.append(']').toString();
4249	>	}
4250	>
4251	>	public final boolean containsAll(Collection<?> c) {
4252	>	if (c != this) {
4253	>	for (Object e : c) {
4254	>	if (e == null || !contains(e))
4255	>	return false;
4256	>	}
4257	>	}
4258	>	return true;
4259	>	}
4260	>
4261	>	public final boolean removeAll(Collection<?> c) {
4262	>	boolean modified = false;
4263	>	for (Iterator<E> it = iterator(); it.hasNext();) {
4264	>	if (c.contains(it.next())) {
4265	>	it.remove();
4266	>	modified = true;
4267	>	}
4268	>	}
4269	>	return modified;
4270	>	}
4271	>
4272	>	public final boolean retainAll(Collection<?> c) {
4273	>	boolean modified = false;
4274	>	for (Iterator<E> it = iterator(); it.hasNext();) {
4275	>	if (!c.contains(it.next())) {
4276	>	it.remove();
4277	>	modified = true;
4278	>	}
4279	>	}
4280	>	return modified;
4281	>	}
4282	>
4283		}
4284
4285		/**
4286	<	* Returns a string representation of this map.  The string
4287	<	* representation consists of a list of key-value mappings (in no
4288	<	* particular order) enclosed in braces ("{@code {}}").  Adjacent
4289	<	* mappings are separated by the characters {@code ", "} (comma
4290	<	* and space).  Each key-value mapping is rendered as the key
4291	<	* followed by an equals sign ("{@code =}") followed by the
4292	<	* associated value.
4286	>	* A view of a ConcurrentHashMapV8 as a {@link Set} of keys, in
4287	>	* which additions may optionally be enabled by mapping to a
4288	>	* common value.  This class cannot be directly instantiated.
4289	>	* See {@link #keySet() keySet()},
4290	>	* {@link #keySet(Object) keySet(V)},
4291	>	* {@link #newKeySet() newKeySet()},
4292	>	* {@link #newKeySet(int) newKeySet(int)}.
4293		*
4294	<	* @return a string representation of this map
4294	>	* @since 1.8
4295		*/
4296	<	public String toString() {
4297	<	return new HashIterator().mapToString();
4296	>	public static class KeySetView<K,V> extends CollectionView<K,V,K>
4297	>	implements Set<K>, java.io.Serializable {
4298	>	private static final long serialVersionUID = 7249069246763182397L;
4299	>	private final V value;
4300	>	KeySetView(ConcurrentHashMapV8<K,V> map, V value) {  // non-public
4301	>	super(map);
4302	>	this.value = value;
4303	>	}
4304	>
4305	>	/**
4306	>	* Returns the default mapped value for additions,
4307	>	* or {@code null} if additions are not supported.
4308	>	*
4309	>	* @return the default mapped value for additions, or {@code null}
4310	>	* if not supported
4311	>	*/
4312	>	public V getMappedValue() { return value; }
4313	>
4314	>	/**
4315	>	* {@inheritDoc}
4316	>	* @throws NullPointerException if the specified key is null
4317	>	*/
4318	>	public boolean contains(Object o) { return map.containsKey(o); }
4319	>
4320	>	/**
4321	>	* Removes the key from this map view, by removing the key (and its
4322	>	* corresponding value) from the backing map.  This method does
4323	>	* nothing if the key is not in the map.
4324	>	*
4325	>	* @param  o the key to be removed from the backing map
4326	>	* @return {@code true} if the backing map contained the specified key
4327	>	* @throws NullPointerException if the specified key is null
4328	>	*/
4329	>	public boolean remove(Object o) { return map.remove(o) != null; }
4330	>
4331	>	/**
4332	>	* @return an iterator over the keys of the backing map
4333	>	*/
4334	>	public Iterator<K> iterator() {
4335	>	Node<K,V>[] t;
4336	>	ConcurrentHashMapV8<K,V> m = map;
4337	>	int f = (t = m.table) == null ? 0 : t.length;
4338	>	return new KeyIterator<K,V>(t, f, 0, f, m);
4339	>	}
4340	>
4341	>	/**
4342	>	* Adds the specified key to this set view by mapping the key to
4343	>	* the default mapped value in the backing map, if defined.
4344	>	*
4345	>	* @param e key to be added
4346	>	* @return {@code true} if this set changed as a result of the call
4347	>	* @throws NullPointerException if the specified key is null
4348	>	* @throws UnsupportedOperationException if no default mapped value
4349	>	* for additions was provided
4350	>	*/
4351	>	public boolean add(K e) {
4352	>	V v;
4353	>	if ((v = value) == null)
4354	>	throw new UnsupportedOperationException();
4355	>	return map.putVal(e, v, true) == null;
4356	>	}
4357	>
4358	>	/**
4359	>	* Adds all of the elements in the specified collection to this set,
4360	>	* as if by calling {@link #add} on each one.
4361	>	*
4362	>	* @param c the elements to be inserted into this set
4363	>	* @return {@code true} if this set changed as a result of the call
4364	>	* @throws NullPointerException if the collection or any of its
4365	>	* elements are {@code null}
4366	>	* @throws UnsupportedOperationException if no default mapped value
4367	>	* for additions was provided
4368	>	*/
4369	>	public boolean addAll(Collection<? extends K> c) {
4370	>	boolean added = false;
4371	>	V v;
4372	>	if ((v = value) == null)
4373	>	throw new UnsupportedOperationException();
4374	>	for (K e : c) {
4375	>	if (map.putVal(e, v, true) == null)
4376	>	added = true;
4377	>	}
4378	>	return added;
4379	>	}
4380	>
4381	>	public int hashCode() {
4382	>	int h = 0;
4383	>	for (K e : this)
4384	>	h += e.hashCode();
4385	>	return h;
4386	>	}
4387	>
4388	>	public boolean equals(Object o) {
4389	>	Set<?> c;
4390	>	return ((o instanceof Set) &&
4391	>	((c = (Set<?>)o) == this ||
4392	>	(containsAll(c) && c.containsAll(this))));
4393	>	}
4394	>
4395	>	public ConcurrentHashMapSpliterator<K> spliterator() {
4396	>	Node<K,V>[] t;
4397	>	ConcurrentHashMapV8<K,V> m = map;
4398	>	long n = m.sumCount();
4399	>	int f = (t = m.table) == null ? 0 : t.length;
4400	>	return new KeySpliterator<K,V>(t, f, 0, f, n < 0L ? 0L : n);
4401	>	}
4402	>
4403	>	public void forEach(Action<? super K> action) {
4404	>	if (action == null) throw new NullPointerException();
4405	>	Node<K,V>[] t;
4406	>	if ((t = map.table) != null) {
4407	>	Traverser<K,V> it = new Traverser<K,V>(t, t.length, 0, t.length);
4408	>	for (Node<K,V> p; (p = it.advance()) != null; )
4409	>	action.apply(p.key);
4410	>	}
4411	>	}
4412		}
4413
4414		/**
4415	<	* Compares the specified object with this map for equality.
4416	<	* Returns {@code true} if the given object is a map with the same
4417	<	* mappings as this map.  This operation may return misleading
1357	<	* results if either map is concurrently modified during execution
1358	<	* of this method.
1359	<	*
1360	<	* @param o object to be compared for equality with this map
1361	<	* @return {@code true} if the specified object is equal to this map
4415	>	* A view of a ConcurrentHashMapV8 as a {@link Collection} of
4416	>	* values, in which additions are disabled. This class cannot be
4417	>	* directly instantiated. See {@link #values()}.
4418		*/
4419	<	public boolean equals(Object o) {
4420	<	if (o == this)
4421	<	return true;
4422	<	if (!(o instanceof Map))
4423	<	return false;
4424	<	Map<?,?> m = (Map<?,?>) o;
4425	<	try {
4426	<	for (Map.Entry<K,V> e : this.entrySet())
4427	<	if (! e.getValue().equals(m.get(e.getKey())))
4428	<	return false;
4429	<	for (Map.Entry<?,?> e : m.entrySet()) {
4430	<	Object k = e.getKey();
4431	<	Object v = e.getValue();
4432	<	if (k == null || v == null || !v.equals(get(k)))
4433	<	return false;
4419	>	static final class ValuesView<K,V> extends CollectionView<K,V,V>
4420	>	implements Collection<V>, java.io.Serializable {
4421	>	private static final long serialVersionUID = 2249069246763182397L;
4422	>	ValuesView(ConcurrentHashMapV8<K,V> map) { super(map); }
4423	>	public final boolean contains(Object o) {
4424	>	return map.containsValue(o);
4425	>	}
4426	>
4427	>	public final boolean remove(Object o) {
4428	>	if (o != null) {
4429	>	for (Iterator<V> it = iterator(); it.hasNext();) {
4430	>	if (o.equals(it.next())) {
4431	>	it.remove();
4432	>	return true;
4433	>	}
4434	>	}
4435		}
1379	–	return true;
1380	–	} catch (ClassCastException unused) {
1381	–	return false;
1382	–	} catch (NullPointerException unused) {
4436		return false;
4437		}
4438	+
4439	+	public final Iterator<V> iterator() {
4440	+	ConcurrentHashMapV8<K,V> m = map;
4441	+	Node<K,V>[] t;
4442	+	int f = (t = m.table) == null ? 0 : t.length;
4443	+	return new ValueIterator<K,V>(t, f, 0, f, m);
4444	+	}
4445	+
4446	+	public final boolean add(V e) {
4447	+	throw new UnsupportedOperationException();
4448	+	}
4449	+	public final boolean addAll(Collection<? extends V> c) {
4450	+	throw new UnsupportedOperationException();
4451	+	}
4452	+
4453	+	public ConcurrentHashMapSpliterator<V> spliterator() {
4454	+	Node<K,V>[] t;
4455	+	ConcurrentHashMapV8<K,V> m = map;
4456	+	long n = m.sumCount();
4457	+	int f = (t = m.table) == null ? 0 : t.length;
4458	+	return new ValueSpliterator<K,V>(t, f, 0, f, n < 0L ? 0L : n);
4459	+	}
4460	+
4461	+	public void forEach(Action<? super V> action) {
4462	+	if (action == null) throw new NullPointerException();
4463	+	Node<K,V>[] t;
4464	+	if ((t = map.table) != null) {
4465	+	Traverser<K,V> it = new Traverser<K,V>(t, t.length, 0, t.length);
4466	+	for (Node<K,V> p; (p = it.advance()) != null; )
4467	+	action.apply(p.val);
4468	+	}
4469	+	}
4470		}
4471
4472		/**
4473	<	* Custom Entry class used by EntryIterator.next(), that relays
4474	<	* setValue changes to the underlying map.
4473	>	* A view of a ConcurrentHashMapV8 as a {@link Set} of (key, value)
4474	>	* entries.  This class cannot be directly instantiated. See
4475	>	* {@link #entrySet()}.
4476		*/
4477	<	final class WriteThroughEntry extends AbstractMap.SimpleEntry<K,V> {
4478	<	@SuppressWarnings("unchecked")
4479	<	WriteThroughEntry(Object k, Object v) {
4480	<	super((K)k, (V)v);
4477	>	static final class EntrySetView<K,V> extends CollectionView<K,V,Map.Entry<K,V>>
4478	>	implements Set<Map.Entry<K,V>>, java.io.Serializable {
4479	>	private static final long serialVersionUID = 2249069246763182397L;
4480	>	EntrySetView(ConcurrentHashMapV8<K,V> map) { super(map); }
4481	>
4482	>	public boolean contains(Object o) {
4483	>	Object k, v, r; Map.Entry<?,?> e;
4484	>	return ((o instanceof Map.Entry) &&
4485	>	(k = (e = (Map.Entry<?,?>)o).getKey()) != null &&
4486	>	(r = map.get(k)) != null &&
4487	>	(v = e.getValue()) != null &&
4488	>	(v == r || v.equals(r)));
4489	>	}
4490	>
4491	>	public boolean remove(Object o) {
4492	>	Object k, v; Map.Entry<?,?> e;
4493	>	return ((o instanceof Map.Entry) &&
4494	>	(k = (e = (Map.Entry<?,?>)o).getKey()) != null &&
4495	>	(v = e.getValue()) != null &&
4496	>	map.remove(k, v));
4497		}
4498
4499		/**
4500	<	* Sets our entry's value and writes through to the map. The
1399	<	* value to return is somewhat arbitrary here. Since a
1400	<	* WriteThroughEntry does not necessarily track asynchronous
1401	<	* changes, the most recent "previous" value could be
1402	<	* different from what we return (or could even have been
1403	<	* removed in which case the put will re-establish). We do not
1404	<	* and cannot guarantee more.
4500	>	* @return an iterator over the entries of the backing map
4501		*/
4502	<	public V setValue(V value) {
4503	<	if (value == null) throw new NullPointerException();
4504	<	V v = super.setValue(value);
4505	<	ConcurrentHashMapV8.this.put(getKey(), value);
4506	<	return v;
4502	>	public Iterator<Map.Entry<K,V>> iterator() {
4503	>	ConcurrentHashMapV8<K,V> m = map;
4504	>	Node<K,V>[] t;
4505	>	int f = (t = m.table) == null ? 0 : t.length;
4506	>	return new EntryIterator<K,V>(t, f, 0, f, m);
4507	>	}
4508	>
4509	>	public boolean add(Entry<K,V> e) {
4510	>	return map.putVal(e.getKey(), e.getValue(), false) == null;
4511	>	}
4512	>
4513	>	public boolean addAll(Collection<? extends Entry<K,V>> c) {
4514	>	boolean added = false;
4515	>	for (Entry<K,V> e : c) {
4516	>	if (add(e))
4517	>	added = true;
4518	>	}
4519	>	return added;
4520	>	}
4521	>
4522	>	public final int hashCode() {
4523	>	int h = 0;
4524	>	Node<K,V>[] t;
4525	>	if ((t = map.table) != null) {
4526	>	Traverser<K,V> it = new Traverser<K,V>(t, t.length, 0, t.length);
4527	>	for (Node<K,V> p; (p = it.advance()) != null; ) {
4528	>	h += p.hashCode();
4529	>	}
4530	>	}
4531	>	return h;
4532		}
4533	+
4534	+	public final boolean equals(Object o) {
4535	+	Set<?> c;
4536	+	return ((o instanceof Set) &&
4537	+	((c = (Set<?>)o) == this ||
4538	+	(containsAll(c) && c.containsAll(this))));
4539	+	}
4540	+
4541	+	public ConcurrentHashMapSpliterator<Map.Entry<K,V>> spliterator() {
4542	+	Node<K,V>[] t;
4543	+	ConcurrentHashMapV8<K,V> m = map;
4544	+	long n = m.sumCount();
4545	+	int f = (t = m.table) == null ? 0 : t.length;
4546	+	return new EntrySpliterator<K,V>(t, f, 0, f, n < 0L ? 0L : n, m);
4547	+	}
4548	+
4549	+	public void forEach(Action<? super Map.Entry<K,V>> action) {
4550	+	if (action == null) throw new NullPointerException();
4551	+	Node<K,V>[] t;
4552	+	if ((t = map.table) != null) {
4553	+	Traverser<K,V> it = new Traverser<K,V>(t, t.length, 0, t.length);
4554	+	for (Node<K,V> p; (p = it.advance()) != null; )
4555	+	action.apply(new MapEntry<K,V>(p.key, p.val, map));
4556	+	}
4557	+	}
4558	+
4559		}
4560
4561	<	final class KeyIterator extends HashIterator
4562	<	implements Iterator<K>, Enumeration<K> {
4563	<	@SuppressWarnings("unchecked")
4564	<	public final K next()        { return (K)super.nextKey(); }
4565	<	@SuppressWarnings("unchecked")
4566	<	public final K nextElement() { return (K)super.nextKey(); }
4561	>	// -------------------------------------------------------
4562	>
4563	>	/**
4564	>	* Base class for bulk tasks. Repeats some fields and code from
4565	>	* class Traverser, because we need to subclass CountedCompleter.
4566	>	*/
4567	>	abstract static class BulkTask<K,V,R> extends CountedCompleter<R> {
4568	>	Node<K,V>[] tab;        // same as Traverser
4569	>	Node<K,V> next;
4570	>	int index;
4571	>	int baseIndex;
4572	>	int baseLimit;
4573	>	final int baseSize;
4574	>	int batch;              // split control
4575	>
4576	>	BulkTask(BulkTask<K,V,?> par, int b, int i, int f, Node<K,V>[] t) {
4577	>	super(par);
4578	>	this.batch = b;
4579	>	this.index = this.baseIndex = i;
4580	>	if ((this.tab = t) == null)
4581	>	this.baseSize = this.baseLimit = 0;
4582	>	else if (par == null)
4583	>	this.baseSize = this.baseLimit = t.length;
4584	>	else {
4585	>	this.baseLimit = f;
4586	>	this.baseSize = par.baseSize;
4587	>	}
4588	>	}
4589	>
4590	>	/**
4591	>	* Same as Traverser version
4592	>	*/
4593	>	final Node<K,V> advance() {
4594	>	Node<K,V> e;
4595	>	if ((e = next) != null)
4596	>	e = e.next;
4597	>	for (;;) {
4598	>	Node<K,V>[] t; int i, n; K ek;  // must use locals in checks
4599	>	if (e != null)
4600	>	return next = e;
4601	>	if (baseIndex >= baseLimit || (t = tab) == null ||
4602	>	(n = t.length) <= (i = index) || i < 0)
4603	>	return next = null;
4604	>	if ((e = tabAt(t, index)) != null && e.hash < 0) {
4605	>	if (e instanceof ForwardingNode) {
4606	>	tab = ((ForwardingNode<K,V>)e).nextTable;
4607	>	e = null;
4608	>	continue;
4609	>	}
4610	>	else if (e instanceof TreeBin)
4611	>	e = ((TreeBin<K,V>)e).first;
4612	>	else
4613	>	e = null;
4614	>	}
4615	>	if ((index += baseSize) >= n)
4616	>	index = ++baseIndex;    // visit upper slots if present
4617	>	}
4618	>	}
4619		}
4620
4621	<	final class ValueIterator extends HashIterator
4622	<	implements Iterator<V>, Enumeration<V> {
4623	<	@SuppressWarnings("unchecked")
4624	<	public final V next()        { return (V)super.nextValue(); }
4625	<	@SuppressWarnings("unchecked")
4626	<	public final V nextElement() { return (V)super.nextValue(); }
4621	>	/*
4622	>	* Task classes. Coded in a regular but ugly format/style to
4623	>	* simplify checks that each variant differs in the right way from
4624	>	* others. The null screenings exist because compilers cannot tell
4625	>	* that we've already null-checked task arguments, so we force
4626	>	* simplest hoisted bypass to help avoid convoluted traps.
4627	>	*/
4628	>	@SuppressWarnings("serial")
4629	>	static final class ForEachKeyTask<K,V>
4630	>	extends BulkTask<K,V,Void> {
4631	>	final Action<? super K> action;
4632	>	ForEachKeyTask
4633	>	(BulkTask<K,V,?> p, int b, int i, int f, Node<K,V>[] t,
4634	>	Action<? super K> action) {
4635	>	super(p, b, i, f, t);
4636	>	this.action = action;
4637	>	}
4638	>	public final void compute() {
4639	>	final Action<? super K> action;
4640	>	if ((action = this.action) != null) {
4641	>	for (int i = baseIndex, f, h; batch > 0 &&
4642	>	(h = ((f = baseLimit) + i) >>> 1) > i;) {
4643	>	addToPendingCount(1);
4644	>	new ForEachKeyTask<K,V>
4645	>	(this, batch >>>= 1, baseLimit = h, f, tab,
4646	>	action).fork();
4647	>	}
4648	>	for (Node<K,V> p; (p = advance()) != null;)
4649	>	action.apply(p.key);
4650	>	propagateCompletion();
4651	>	}
4652	>	}
4653		}
4654
4655	<	final class EntryIterator extends HashIterator
4656	<	implements Iterator<Entry<K,V>> {
4657	<	public final Map.Entry<K,V> next() { return super.nextEntry(); }
4655	>	@SuppressWarnings("serial")
4656	>	static final class ForEachValueTask<K,V>
4657	>	extends BulkTask<K,V,Void> {
4658	>	final Action<? super V> action;
4659	>	ForEachValueTask
4660	>	(BulkTask<K,V,?> p, int b, int i, int f, Node<K,V>[] t,
4661	>	Action<? super V> action) {
4662	>	super(p, b, i, f, t);
4663	>	this.action = action;
4664	>	}
4665	>	public final void compute() {
4666	>	final Action<? super V> action;
4667	>	if ((action = this.action) != null) {
4668	>	for (int i = baseIndex, f, h; batch > 0 &&
4669	>	(h = ((f = baseLimit) + i) >>> 1) > i;) {
4670	>	addToPendingCount(1);
4671	>	new ForEachValueTask<K,V>
4672	>	(this, batch >>>= 1, baseLimit = h, f, tab,
4673	>	action).fork();
4674	>	}
4675	>	for (Node<K,V> p; (p = advance()) != null;)
4676	>	action.apply(p.val);
4677	>	propagateCompletion();
4678	>	}
4679	>	}
4680		}
4681
4682	<	final class KeySet extends AbstractSet<K> {
4683	<	public int size() {
4684	<	return ConcurrentHashMapV8.this.size();
4682	>	@SuppressWarnings("serial")
4683	>	static final class ForEachEntryTask<K,V>
4684	>	extends BulkTask<K,V,Void> {
4685	>	final Action<? super Entry<K,V>> action;
4686	>	ForEachEntryTask
4687	>	(BulkTask<K,V,?> p, int b, int i, int f, Node<K,V>[] t,
4688	>	Action<? super Entry<K,V>> action) {
4689	>	super(p, b, i, f, t);
4690	>	this.action = action;
4691	>	}
4692	>	public final void compute() {
4693	>	final Action<? super Entry<K,V>> action;
4694	>	if ((action = this.action) != null) {
4695	>	for (int i = baseIndex, f, h; batch > 0 &&
4696	>	(h = ((f = baseLimit) + i) >>> 1) > i;) {
4697	>	addToPendingCount(1);
4698	>	new ForEachEntryTask<K,V>
4699	>	(this, batch >>>= 1, baseLimit = h, f, tab,
4700	>	action).fork();
4701	>	}
4702	>	for (Node<K,V> p; (p = advance()) != null; )
4703	>	action.apply(p);
4704	>	propagateCompletion();
4705	>	}
4706		}
4707	<	public boolean isEmpty() {
4708	<	return ConcurrentHashMapV8.this.isEmpty();
4707	>	}
4708	>
4709	>	@SuppressWarnings("serial")
4710	>	static final class ForEachMappingTask<K,V>
4711	>	extends BulkTask<K,V,Void> {
4712	>	final BiAction<? super K, ? super V> action;
4713	>	ForEachMappingTask
4714	>	(BulkTask<K,V,?> p, int b, int i, int f, Node<K,V>[] t,
4715	>	BiAction<? super K,? super V> action) {
4716	>	super(p, b, i, f, t);
4717	>	this.action = action;
4718	>	}
4719	>	public final void compute() {
4720	>	final BiAction<? super K, ? super V> action;
4721	>	if ((action = this.action) != null) {
4722	>	for (int i = baseIndex, f, h; batch > 0 &&
4723	>	(h = ((f = baseLimit) + i) >>> 1) > i;) {
4724	>	addToPendingCount(1);
4725	>	new ForEachMappingTask<K,V>
4726	>	(this, batch >>>= 1, baseLimit = h, f, tab,
4727	>	action).fork();
4728	>	}
4729	>	for (Node<K,V> p; (p = advance()) != null; )
4730	>	action.apply(p.key, p.val);
4731	>	propagateCompletion();
4732	>	}
4733		}
4734	<	public void clear() {
4735	<	ConcurrentHashMapV8.this.clear();
4734	>	}
4735	>
4736	>	@SuppressWarnings("serial")
4737	>	static final class ForEachTransformedKeyTask<K,V,U>
4738	>	extends BulkTask<K,V,Void> {
4739	>	final Fun<? super K, ? extends U> transformer;
4740	>	final Action<? super U> action;
4741	>	ForEachTransformedKeyTask
4742	>	(BulkTask<K,V,?> p, int b, int i, int f, Node<K,V>[] t,
4743	>	Fun<? super K, ? extends U> transformer, Action<? super U> action) {
4744	>	super(p, b, i, f, t);
4745	>	this.transformer = transformer; this.action = action;
4746	>	}
4747	>	public final void compute() {
4748	>	final Fun<? super K, ? extends U> transformer;
4749	>	final Action<? super U> action;
4750	>	if ((transformer = this.transformer) != null &&
4751	>	(action = this.action) != null) {
4752	>	for (int i = baseIndex, f, h; batch > 0 &&
4753	>	(h = ((f = baseLimit) + i) >>> 1) > i;) {
4754	>	addToPendingCount(1);
4755	>	new ForEachTransformedKeyTask<K,V,U>
4756	>	(this, batch >>>= 1, baseLimit = h, f, tab,
4757	>	transformer, action).fork();
4758	>	}
4759	>	for (Node<K,V> p; (p = advance()) != null; ) {
4760	>	U u;
4761	>	if ((u = transformer.apply(p.key)) != null)
4762	>	action.apply(u);
4763	>	}
4764	>	propagateCompletion();
4765	>	}
4766		}
4767	<	public Iterator<K> iterator() {
4768	<	return new KeyIterator();
4767	>	}
4768	>
4769	>	@SuppressWarnings("serial")
4770	>	static final class ForEachTransformedValueTask<K,V,U>
4771	>	extends BulkTask<K,V,Void> {
4772	>	final Fun<? super V, ? extends U> transformer;
4773	>	final Action<? super U> action;
4774	>	ForEachTransformedValueTask
4775	>	(BulkTask<K,V,?> p, int b, int i, int f, Node<K,V>[] t,
4776	>	Fun<? super V, ? extends U> transformer, Action<? super U> action) {
4777	>	super(p, b, i, f, t);
4778	>	this.transformer = transformer; this.action = action;
4779	>	}
4780	>	public final void compute() {
4781	>	final Fun<? super V, ? extends U> transformer;
4782	>	final Action<? super U> action;
4783	>	if ((transformer = this.transformer) != null &&
4784	>	(action = this.action) != null) {
4785	>	for (int i = baseIndex, f, h; batch > 0 &&
4786	>	(h = ((f = baseLimit) + i) >>> 1) > i;) {
4787	>	addToPendingCount(1);
4788	>	new ForEachTransformedValueTask<K,V,U>
4789	>	(this, batch >>>= 1, baseLimit = h, f, tab,
4790	>	transformer, action).fork();
4791	>	}
4792	>	for (Node<K,V> p; (p = advance()) != null; ) {
4793	>	U u;
4794	>	if ((u = transformer.apply(p.val)) != null)
4795	>	action.apply(u);
4796	>	}
4797	>	propagateCompletion();
4798	>	}
4799		}
4800	<	public boolean contains(Object o) {
4801	<	return ConcurrentHashMapV8.this.containsKey(o);
4800	>	}
4801	>
4802	>	@SuppressWarnings("serial")
4803	>	static final class ForEachTransformedEntryTask<K,V,U>
4804	>	extends BulkTask<K,V,Void> {
4805	>	final Fun<Map.Entry<K,V>, ? extends U> transformer;
4806	>	final Action<? super U> action;
4807	>	ForEachTransformedEntryTask
4808	>	(BulkTask<K,V,?> p, int b, int i, int f, Node<K,V>[] t,
4809	>	Fun<Map.Entry<K,V>, ? extends U> transformer, Action<? super U> action) {
4810	>	super(p, b, i, f, t);
4811	>	this.transformer = transformer; this.action = action;
4812	>	}
4813	>	public final void compute() {
4814	>	final Fun<Map.Entry<K,V>, ? extends U> transformer;
4815	>	final Action<? super U> action;
4816	>	if ((transformer = this.transformer) != null &&
4817	>	(action = this.action) != null) {
4818	>	for (int i = baseIndex, f, h; batch > 0 &&
4819	>	(h = ((f = baseLimit) + i) >>> 1) > i;) {
4820	>	addToPendingCount(1);
4821	>	new ForEachTransformedEntryTask<K,V,U>
4822	>	(this, batch >>>= 1, baseLimit = h, f, tab,
4823	>	transformer, action).fork();
4824	>	}
4825	>	for (Node<K,V> p; (p = advance()) != null; ) {
4826	>	U u;
4827	>	if ((u = transformer.apply(p)) != null)
4828	>	action.apply(u);
4829	>	}
4830	>	propagateCompletion();
4831	>	}
4832		}
4833	<	public boolean remove(Object o) {
4834	<	return ConcurrentHashMapV8.this.remove(o) != null;
4833	>	}
4834	>
4835	>	@SuppressWarnings("serial")
4836	>	static final class ForEachTransformedMappingTask<K,V,U>
4837	>	extends BulkTask<K,V,Void> {
4838	>	final BiFun<? super K, ? super V, ? extends U> transformer;
4839	>	final Action<? super U> action;
4840	>	ForEachTransformedMappingTask
4841	>	(BulkTask<K,V,?> p, int b, int i, int f, Node<K,V>[] t,
4842	>	BiFun<? super K, ? super V, ? extends U> transformer,
4843	>	Action<? super U> action) {
4844	>	super(p, b, i, f, t);
4845	>	this.transformer = transformer; this.action = action;
4846	>	}
4847	>	public final void compute() {
4848	>	final BiFun<? super K, ? super V, ? extends U> transformer;
4849	>	final Action<? super U> action;
4850	>	if ((transformer = this.transformer) != null &&
4851	>	(action = this.action) != null) {
4852	>	for (int i = baseIndex, f, h; batch > 0 &&
4853	>	(h = ((f = baseLimit) + i) >>> 1) > i;) {
4854	>	addToPendingCount(1);
4855	>	new ForEachTransformedMappingTask<K,V,U>
4856	>	(this, batch >>>= 1, baseLimit = h, f, tab,
4857	>	transformer, action).fork();
4858	>	}
4859	>	for (Node<K,V> p; (p = advance()) != null; ) {
4860	>	U u;
4861	>	if ((u = transformer.apply(p.key, p.val)) != null)
4862	>	action.apply(u);
4863	>	}
4864	>	propagateCompletion();
4865	>	}
4866		}
4867		}
4868
4869	<	final class Values extends AbstractCollection<V> {
4870	<	public int size() {
4871	<	return ConcurrentHashMapV8.this.size();
4869	>	@SuppressWarnings("serial")
4870	>	static final class SearchKeysTask<K,V,U>
4871	>	extends BulkTask<K,V,U> {
4872	>	final Fun<? super K, ? extends U> searchFunction;
4873	>	final AtomicReference<U> result;
4874	>	SearchKeysTask
4875	>	(BulkTask<K,V,?> p, int b, int i, int f, Node<K,V>[] t,
4876	>	Fun<? super K, ? extends U> searchFunction,
4877	>	AtomicReference<U> result) {
4878	>	super(p, b, i, f, t);
4879	>	this.searchFunction = searchFunction; this.result = result;
4880	>	}
4881	>	public final U getRawResult() { return result.get(); }
4882	>	public final void compute() {
4883	>	final Fun<? super K, ? extends U> searchFunction;
4884	>	final AtomicReference<U> result;
4885	>	if ((searchFunction = this.searchFunction) != null &&
4886	>	(result = this.result) != null) {
4887	>	for (int i = baseIndex, f, h; batch > 0 &&
4888	>	(h = ((f = baseLimit) + i) >>> 1) > i;) {
4889	>	if (result.get() != null)
4890	>	return;
4891	>	addToPendingCount(1);
4892	>	new SearchKeysTask<K,V,U>
4893	>	(this, batch >>>= 1, baseLimit = h, f, tab,
4894	>	searchFunction, result).fork();
4895	>	}
4896	>	while (result.get() == null) {
4897	>	U u;
4898	>	Node<K,V> p;
4899	>	if ((p = advance()) == null) {
4900	>	propagateCompletion();
4901	>	break;
4902	>	}
4903	>	if ((u = searchFunction.apply(p.key)) != null) {
4904	>	if (result.compareAndSet(null, u))
4905	>	quietlyCompleteRoot();
4906	>	break;
4907	>	}
4908	>	}
4909	>	}
4910		}
4911	<	public boolean isEmpty() {
4912	<	return ConcurrentHashMapV8.this.isEmpty();
4911	>	}
4912	>
4913	>	@SuppressWarnings("serial")
4914	>	static final class SearchValuesTask<K,V,U>
4915	>	extends BulkTask<K,V,U> {
4916	>	final Fun<? super V, ? extends U> searchFunction;
4917	>	final AtomicReference<U> result;
4918	>	SearchValuesTask
4919	>	(BulkTask<K,V,?> p, int b, int i, int f, Node<K,V>[] t,
4920	>	Fun<? super V, ? extends U> searchFunction,
4921	>	AtomicReference<U> result) {
4922	>	super(p, b, i, f, t);
4923	>	this.searchFunction = searchFunction; this.result = result;
4924	>	}
4925	>	public final U getRawResult() { return result.get(); }
4926	>	public final void compute() {
4927	>	final Fun<? super V, ? extends U> searchFunction;
4928	>	final AtomicReference<U> result;
4929	>	if ((searchFunction = this.searchFunction) != null &&
4930	>	(result = this.result) != null) {
4931	>	for (int i = baseIndex, f, h; batch > 0 &&
4932	>	(h = ((f = baseLimit) + i) >>> 1) > i;) {
4933	>	if (result.get() != null)
4934	>	return;
4935	>	addToPendingCount(1);
4936	>	new SearchValuesTask<K,V,U>
4937	>	(this, batch >>>= 1, baseLimit = h, f, tab,
4938	>	searchFunction, result).fork();
4939	>	}
4940	>	while (result.get() == null) {
4941	>	U u;
4942	>	Node<K,V> p;
4943	>	if ((p = advance()) == null) {
4944	>	propagateCompletion();
4945	>	break;
4946	>	}
4947	>	if ((u = searchFunction.apply(p.val)) != null) {
4948	>	if (result.compareAndSet(null, u))
4949	>	quietlyCompleteRoot();
4950	>	break;
4951	>	}
4952	>	}
4953	>	}
4954		}
4955	<	public void clear() {
4956	<	ConcurrentHashMapV8.this.clear();
4955	>	}
4956	>
4957	>	@SuppressWarnings("serial")
4958	>	static final class SearchEntriesTask<K,V,U>
4959	>	extends BulkTask<K,V,U> {
4960	>	final Fun<Entry<K,V>, ? extends U> searchFunction;
4961	>	final AtomicReference<U> result;
4962	>	SearchEntriesTask
4963	>	(BulkTask<K,V,?> p, int b, int i, int f, Node<K,V>[] t,
4964	>	Fun<Entry<K,V>, ? extends U> searchFunction,
4965	>	AtomicReference<U> result) {
4966	>	super(p, b, i, f, t);
4967	>	this.searchFunction = searchFunction; this.result = result;
4968	>	}
4969	>	public final U getRawResult() { return result.get(); }
4970	>	public final void compute() {
4971	>	final Fun<Entry<K,V>, ? extends U> searchFunction;
4972	>	final AtomicReference<U> result;
4973	>	if ((searchFunction = this.searchFunction) != null &&
4974	>	(result = this.result) != null) {
4975	>	for (int i = baseIndex, f, h; batch > 0 &&
4976	>	(h = ((f = baseLimit) + i) >>> 1) > i;) {
4977	>	if (result.get() != null)
4978	>	return;
4979	>	addToPendingCount(1);
4980	>	new SearchEntriesTask<K,V,U>
4981	>	(this, batch >>>= 1, baseLimit = h, f, tab,
4982	>	searchFunction, result).fork();
4983	>	}
4984	>	while (result.get() == null) {
4985	>	U u;
4986	>	Node<K,V> p;
4987	>	if ((p = advance()) == null) {
4988	>	propagateCompletion();
4989	>	break;
4990	>	}
4991	>	if ((u = searchFunction.apply(p)) != null) {
4992	>	if (result.compareAndSet(null, u))
4993	>	quietlyCompleteRoot();
4994	>	return;
4995	>	}
4996	>	}
4997	>	}
4998		}
4999	<	public Iterator<V> iterator() {
5000	<	return new ValueIterator();
4999	>	}
5000	>
5001	>	@SuppressWarnings("serial")
5002	>	static final class SearchMappingsTask<K,V,U>
5003	>	extends BulkTask<K,V,U> {
5004	>	final BiFun<? super K, ? super V, ? extends U> searchFunction;
5005	>	final AtomicReference<U> result;
5006	>	SearchMappingsTask
5007	>	(BulkTask<K,V,?> p, int b, int i, int f, Node<K,V>[] t,
5008	>	BiFun<? super K, ? super V, ? extends U> searchFunction,
5009	>	AtomicReference<U> result) {
5010	>	super(p, b, i, f, t);
5011	>	this.searchFunction = searchFunction; this.result = result;
5012	>	}
5013	>	public final U getRawResult() { return result.get(); }
5014	>	public final void compute() {
5015	>	final BiFun<? super K, ? super V, ? extends U> searchFunction;
5016	>	final AtomicReference<U> result;
5017	>	if ((searchFunction = this.searchFunction) != null &&
5018	>	(result = this.result) != null) {
5019	>	for (int i = baseIndex, f, h; batch > 0 &&
5020	>	(h = ((f = baseLimit) + i) >>> 1) > i;) {
5021	>	if (result.get() != null)
5022	>	return;
5023	>	addToPendingCount(1);
5024	>	new SearchMappingsTask<K,V,U>
5025	>	(this, batch >>>= 1, baseLimit = h, f, tab,
5026	>	searchFunction, result).fork();
5027	>	}
5028	>	while (result.get() == null) {
5029	>	U u;
5030	>	Node<K,V> p;
5031	>	if ((p = advance()) == null) {
5032	>	propagateCompletion();
5033	>	break;
5034	>	}
5035	>	if ((u = searchFunction.apply(p.key, p.val)) != null) {
5036	>	if (result.compareAndSet(null, u))
5037	>	quietlyCompleteRoot();
5038	>	break;
5039	>	}
5040	>	}
5041	>	}
5042		}
5043	<	public boolean contains(Object o) {
5044	<	return ConcurrentHashMapV8.this.containsValue(o);
5043	>	}
5044	>
5045	>	@SuppressWarnings("serial")
5046	>	static final class ReduceKeysTask<K,V>
5047	>	extends BulkTask<K,V,K> {
5048	>	final BiFun<? super K, ? super K, ? extends K> reducer;
5049	>	K result;
5050	>	ReduceKeysTask<K,V> rights, nextRight;
5051	>	ReduceKeysTask
5052	>	(BulkTask<K,V,?> p, int b, int i, int f, Node<K,V>[] t,
5053	>	ReduceKeysTask<K,V> nextRight,
5054	>	BiFun<? super K, ? super K, ? extends K> reducer) {
5055	>	super(p, b, i, f, t); this.nextRight = nextRight;
5056	>	this.reducer = reducer;
5057	>	}
5058	>	public final K getRawResult() { return result; }
5059	>	public final void compute() {
5060	>	final BiFun<? super K, ? super K, ? extends K> reducer;
5061	>	if ((reducer = this.reducer) != null) {
5062	>	for (int i = baseIndex, f, h; batch > 0 &&
5063	>	(h = ((f = baseLimit) + i) >>> 1) > i;) {
5064	>	addToPendingCount(1);
5065	>	(rights = new ReduceKeysTask<K,V>
5066	>	(this, batch >>>= 1, baseLimit = h, f, tab,
5067	>	rights, reducer)).fork();
5068	>	}
5069	>	K r = null;
5070	>	for (Node<K,V> p; (p = advance()) != null; ) {
5071	>	K u = p.key;
5072	>	r = (r == null) ? u : u == null ? r : reducer.apply(r, u);
5073	>	}
5074	>	result = r;
5075	>	CountedCompleter<?> c;
5076	>	for (c = firstComplete(); c != null; c = c.nextComplete()) {
5077	>	@SuppressWarnings("unchecked") ReduceKeysTask<K,V>
5078	>	t = (ReduceKeysTask<K,V>)c,
5079	>	s = t.rights;
5080	>	while (s != null) {
5081	>	K tr, sr;
5082	>	if ((sr = s.result) != null)
5083	>	t.result = (((tr = t.result) == null) ? sr :
5084	>	reducer.apply(tr, sr));
5085	>	s = t.rights = s.nextRight;
5086	>	}
5087	>	}
5088	>	}
5089		}
5090		}
5091
5092	<	final class EntrySet extends AbstractSet<Map.Entry<K,V>> {
5093	<	public int size() {
5094	<	return ConcurrentHashMapV8.this.size();
5092	>	@SuppressWarnings("serial")
5093	>	static final class ReduceValuesTask<K,V>
5094	>	extends BulkTask<K,V,V> {
5095	>	final BiFun<? super V, ? super V, ? extends V> reducer;
5096	>	V result;
5097	>	ReduceValuesTask<K,V> rights, nextRight;
5098	>	ReduceValuesTask
5099	>	(BulkTask<K,V,?> p, int b, int i, int f, Node<K,V>[] t,
5100	>	ReduceValuesTask<K,V> nextRight,
5101	>	BiFun<? super V, ? super V, ? extends V> reducer) {
5102	>	super(p, b, i, f, t); this.nextRight = nextRight;
5103	>	this.reducer = reducer;
5104	>	}
5105	>	public final V getRawResult() { return result; }
5106	>	public final void compute() {
5107	>	final BiFun<? super V, ? super V, ? extends V> reducer;
5108	>	if ((reducer = this.reducer) != null) {
5109	>	for (int i = baseIndex, f, h; batch > 0 &&
5110	>	(h = ((f = baseLimit) + i) >>> 1) > i;) {
5111	>	addToPendingCount(1);
5112	>	(rights = new ReduceValuesTask<K,V>
5113	>	(this, batch >>>= 1, baseLimit = h, f, tab,
5114	>	rights, reducer)).fork();
5115	>	}
5116	>	V r = null;
5117	>	for (Node<K,V> p; (p = advance()) != null; ) {
5118	>	V v = p.val;
5119	>	r = (r == null) ? v : reducer.apply(r, v);
5120	>	}
5121	>	result = r;
5122	>	CountedCompleter<?> c;
5123	>	for (c = firstComplete(); c != null; c = c.nextComplete()) {
5124	>	@SuppressWarnings("unchecked") ReduceValuesTask<K,V>
5125	>	t = (ReduceValuesTask<K,V>)c,
5126	>	s = t.rights;
5127	>	while (s != null) {
5128	>	V tr, sr;
5129	>	if ((sr = s.result) != null)
5130	>	t.result = (((tr = t.result) == null) ? sr :
5131	>	reducer.apply(tr, sr));
5132	>	s = t.rights = s.nextRight;
5133	>	}
5134	>	}
5135	>	}
5136		}
5137	<	public boolean isEmpty() {
5138	<	return ConcurrentHashMapV8.this.isEmpty();
5137	>	}
5138	>
5139	>	@SuppressWarnings("serial")
5140	>	static final class ReduceEntriesTask<K,V>
5141	>	extends BulkTask<K,V,Map.Entry<K,V>> {
5142	>	final BiFun<Map.Entry<K,V>, Map.Entry<K,V>, ? extends Map.Entry<K,V>> reducer;
5143	>	Map.Entry<K,V> result;
5144	>	ReduceEntriesTask<K,V> rights, nextRight;
5145	>	ReduceEntriesTask
5146	>	(BulkTask<K,V,?> p, int b, int i, int f, Node<K,V>[] t,
5147	>	ReduceEntriesTask<K,V> nextRight,
5148	>	BiFun<Entry<K,V>, Map.Entry<K,V>, ? extends Map.Entry<K,V>> reducer) {
5149	>	super(p, b, i, f, t); this.nextRight = nextRight;
5150	>	this.reducer = reducer;
5151	>	}
5152	>	public final Map.Entry<K,V> getRawResult() { return result; }
5153	>	public final void compute() {
5154	>	final BiFun<Map.Entry<K,V>, Map.Entry<K,V>, ? extends Map.Entry<K,V>> reducer;
5155	>	if ((reducer = this.reducer) != null) {
5156	>	for (int i = baseIndex, f, h; batch > 0 &&
5157	>	(h = ((f = baseLimit) + i) >>> 1) > i;) {
5158	>	addToPendingCount(1);
5159	>	(rights = new ReduceEntriesTask<K,V>
5160	>	(this, batch >>>= 1, baseLimit = h, f, tab,
5161	>	rights, reducer)).fork();
5162	>	}
5163	>	Map.Entry<K,V> r = null;
5164	>	for (Node<K,V> p; (p = advance()) != null; )
5165	>	r = (r == null) ? p : reducer.apply(r, p);
5166	>	result = r;
5167	>	CountedCompleter<?> c;
5168	>	for (c = firstComplete(); c != null; c = c.nextComplete()) {
5169	>	@SuppressWarnings("unchecked") ReduceEntriesTask<K,V>
5170	>	t = (ReduceEntriesTask<K,V>)c,
5171	>	s = t.rights;
5172	>	while (s != null) {
5173	>	Map.Entry<K,V> tr, sr;
5174	>	if ((sr = s.result) != null)
5175	>	t.result = (((tr = t.result) == null) ? sr :
5176	>	reducer.apply(tr, sr));
5177	>	s = t.rights = s.nextRight;
5178	>	}
5179	>	}
5180	>	}
5181		}
5182	<	public void clear() {
5183	<	ConcurrentHashMapV8.this.clear();
5182	>	}
5183	>
5184	>	@SuppressWarnings("serial")
5185	>	static final class MapReduceKeysTask<K,V,U>
5186	>	extends BulkTask<K,V,U> {
5187	>	final Fun<? super K, ? extends U> transformer;
5188	>	final BiFun<? super U, ? super U, ? extends U> reducer;
5189	>	U result;
5190	>	MapReduceKeysTask<K,V,U> rights, nextRight;
5191	>	MapReduceKeysTask
5192	>	(BulkTask<K,V,?> p, int b, int i, int f, Node<K,V>[] t,
5193	>	MapReduceKeysTask<K,V,U> nextRight,
5194	>	Fun<? super K, ? extends U> transformer,
5195	>	BiFun<? super U, ? super U, ? extends U> reducer) {
5196	>	super(p, b, i, f, t); this.nextRight = nextRight;
5197	>	this.transformer = transformer;
5198	>	this.reducer = reducer;
5199	>	}
5200	>	public final U getRawResult() { return result; }
5201	>	public final void compute() {
5202	>	final Fun<? super K, ? extends U> transformer;
5203	>	final BiFun<? super U, ? super U, ? extends U> reducer;
5204	>	if ((transformer = this.transformer) != null &&
5205	>	(reducer = this.reducer) != null) {
5206	>	for (int i = baseIndex, f, h; batch > 0 &&
5207	>	(h = ((f = baseLimit) + i) >>> 1) > i;) {
5208	>	addToPendingCount(1);
5209	>	(rights = new MapReduceKeysTask<K,V,U>
5210	>	(this, batch >>>= 1, baseLimit = h, f, tab,
5211	>	rights, transformer, reducer)).fork();
5212	>	}
5213	>	U r = null;
5214	>	for (Node<K,V> p; (p = advance()) != null; ) {
5215	>	U u;
5216	>	if ((u = transformer.apply(p.key)) != null)
5217	>	r = (r == null) ? u : reducer.apply(r, u);
5218	>	}
5219	>	result = r;
5220	>	CountedCompleter<?> c;
5221	>	for (c = firstComplete(); c != null; c = c.nextComplete()) {
5222	>	@SuppressWarnings("unchecked") MapReduceKeysTask<K,V,U>
5223	>	t = (MapReduceKeysTask<K,V,U>)c,
5224	>	s = t.rights;
5225	>	while (s != null) {
5226	>	U tr, sr;
5227	>	if ((sr = s.result) != null)
5228	>	t.result = (((tr = t.result) == null) ? sr :
5229	>	reducer.apply(tr, sr));
5230	>	s = t.rights = s.nextRight;
5231	>	}
5232	>	}
5233	>	}
5234		}
5235	<	public Iterator<Map.Entry<K,V>> iterator() {
5236	<	return new EntryIterator();
5235	>	}
5236	>
5237	>	@SuppressWarnings("serial")
5238	>	static final class MapReduceValuesTask<K,V,U>
5239	>	extends BulkTask<K,V,U> {
5240	>	final Fun<? super V, ? extends U> transformer;
5241	>	final BiFun<? super U, ? super U, ? extends U> reducer;
5242	>	U result;
5243	>	MapReduceValuesTask<K,V,U> rights, nextRight;
5244	>	MapReduceValuesTask
5245	>	(BulkTask<K,V,?> p, int b, int i, int f, Node<K,V>[] t,
5246	>	MapReduceValuesTask<K,V,U> nextRight,
5247	>	Fun<? super V, ? extends U> transformer,
5248	>	BiFun<? super U, ? super U, ? extends U> reducer) {
5249	>	super(p, b, i, f, t); this.nextRight = nextRight;
5250	>	this.transformer = transformer;
5251	>	this.reducer = reducer;
5252	>	}
5253	>	public final U getRawResult() { return result; }
5254	>	public final void compute() {
5255	>	final Fun<? super V, ? extends U> transformer;
5256	>	final BiFun<? super U, ? super U, ? extends U> reducer;
5257	>	if ((transformer = this.transformer) != null &&
5258	>	(reducer = this.reducer) != null) {
5259	>	for (int i = baseIndex, f, h; batch > 0 &&
5260	>	(h = ((f = baseLimit) + i) >>> 1) > i;) {
5261	>	addToPendingCount(1);
5262	>	(rights = new MapReduceValuesTask<K,V,U>
5263	>	(this, batch >>>= 1, baseLimit = h, f, tab,
5264	>	rights, transformer, reducer)).fork();
5265	>	}
5266	>	U r = null;
5267	>	for (Node<K,V> p; (p = advance()) != null; ) {
5268	>	U u;
5269	>	if ((u = transformer.apply(p.val)) != null)
5270	>	r = (r == null) ? u : reducer.apply(r, u);
5271	>	}
5272	>	result = r;
5273	>	CountedCompleter<?> c;
5274	>	for (c = firstComplete(); c != null; c = c.nextComplete()) {
5275	>	@SuppressWarnings("unchecked") MapReduceValuesTask<K,V,U>
5276	>	t = (MapReduceValuesTask<K,V,U>)c,
5277	>	s = t.rights;
5278	>	while (s != null) {
5279	>	U tr, sr;
5280	>	if ((sr = s.result) != null)
5281	>	t.result = (((tr = t.result) == null) ? sr :
5282	>	reducer.apply(tr, sr));
5283	>	s = t.rights = s.nextRight;
5284	>	}
5285	>	}
5286	>	}
5287		}
5288	<	public boolean contains(Object o) {
5289	<	if (!(o instanceof Map.Entry))
5290	<	return false;
5291	<	Map.Entry<?,?> e = (Map.Entry<?,?>)o;
5292	<	V v = ConcurrentHashMapV8.this.get(e.getKey());
5293	<	return v != null && v.equals(e.getValue());
5288	>	}
5289	>
5290	>	@SuppressWarnings("serial")
5291	>	static final class MapReduceEntriesTask<K,V,U>
5292	>	extends BulkTask<K,V,U> {
5293	>	final Fun<Map.Entry<K,V>, ? extends U> transformer;
5294	>	final BiFun<? super U, ? super U, ? extends U> reducer;
5295	>	U result;
5296	>	MapReduceEntriesTask<K,V,U> rights, nextRight;
5297	>	MapReduceEntriesTask
5298	>	(BulkTask<K,V,?> p, int b, int i, int f, Node<K,V>[] t,
5299	>	MapReduceEntriesTask<K,V,U> nextRight,
5300	>	Fun<Map.Entry<K,V>, ? extends U> transformer,
5301	>	BiFun<? super U, ? super U, ? extends U> reducer) {
5302	>	super(p, b, i, f, t); this.nextRight = nextRight;
5303	>	this.transformer = transformer;
5304	>	this.reducer = reducer;
5305	>	}
5306	>	public final U getRawResult() { return result; }
5307	>	public final void compute() {
5308	>	final Fun<Map.Entry<K,V>, ? extends U> transformer;
5309	>	final BiFun<? super U, ? super U, ? extends U> reducer;
5310	>	if ((transformer = this.transformer) != null &&
5311	>	(reducer = this.reducer) != null) {
5312	>	for (int i = baseIndex, f, h; batch > 0 &&
5313	>	(h = ((f = baseLimit) + i) >>> 1) > i;) {
5314	>	addToPendingCount(1);
5315	>	(rights = new MapReduceEntriesTask<K,V,U>
5316	>	(this, batch >>>= 1, baseLimit = h, f, tab,
5317	>	rights, transformer, reducer)).fork();
5318	>	}
5319	>	U r = null;
5320	>	for (Node<K,V> p; (p = advance()) != null; ) {
5321	>	U u;
5322	>	if ((u = transformer.apply(p)) != null)
5323	>	r = (r == null) ? u : reducer.apply(r, u);
5324	>	}
5325	>	result = r;
5326	>	CountedCompleter<?> c;
5327	>	for (c = firstComplete(); c != null; c = c.nextComplete()) {
5328	>	@SuppressWarnings("unchecked") MapReduceEntriesTask<K,V,U>
5329	>	t = (MapReduceEntriesTask<K,V,U>)c,
5330	>	s = t.rights;
5331	>	while (s != null) {
5332	>	U tr, sr;
5333	>	if ((sr = s.result) != null)
5334	>	t.result = (((tr = t.result) == null) ? sr :
5335	>	reducer.apply(tr, sr));
5336	>	s = t.rights = s.nextRight;
5337	>	}
5338	>	}
5339	>	}
5340		}
5341	<	public boolean remove(Object o) {
5342	<	if (!(o instanceof Map.Entry))
5343	<	return false;
5344	<	Map.Entry<?,?> e = (Map.Entry<?,?>)o;
5345	<	return ConcurrentHashMapV8.this.remove(e.getKey(), e.getValue());
5341	>	}
5342	>
5343	>	@SuppressWarnings("serial")
5344	>	static final class MapReduceMappingsTask<K,V,U>
5345	>	extends BulkTask<K,V,U> {
5346	>	final BiFun<? super K, ? super V, ? extends U> transformer;
5347	>	final BiFun<? super U, ? super U, ? extends U> reducer;
5348	>	U result;
5349	>	MapReduceMappingsTask<K,V,U> rights, nextRight;
5350	>	MapReduceMappingsTask
5351	>	(BulkTask<K,V,?> p, int b, int i, int f, Node<K,V>[] t,
5352	>	MapReduceMappingsTask<K,V,U> nextRight,
5353	>	BiFun<? super K, ? super V, ? extends U> transformer,
5354	>	BiFun<? super U, ? super U, ? extends U> reducer) {
5355	>	super(p, b, i, f, t); this.nextRight = nextRight;
5356	>	this.transformer = transformer;
5357	>	this.reducer = reducer;
5358	>	}
5359	>	public final U getRawResult() { return result; }
5360	>	public final void compute() {
5361	>	final BiFun<? super K, ? super V, ? extends U> transformer;
5362	>	final BiFun<? super U, ? super U, ? extends U> reducer;
5363	>	if ((transformer = this.transformer) != null &&
5364	>	(reducer = this.reducer) != null) {
5365	>	for (int i = baseIndex, f, h; batch > 0 &&
5366	>	(h = ((f = baseLimit) + i) >>> 1) > i;) {
5367	>	addToPendingCount(1);
5368	>	(rights = new MapReduceMappingsTask<K,V,U>
5369	>	(this, batch >>>= 1, baseLimit = h, f, tab,
5370	>	rights, transformer, reducer)).fork();
5371	>	}
5372	>	U r = null;
5373	>	for (Node<K,V> p; (p = advance()) != null; ) {
5374	>	U u;
5375	>	if ((u = transformer.apply(p.key, p.val)) != null)
5376	>	r = (r == null) ? u : reducer.apply(r, u);
5377	>	}
5378	>	result = r;
5379	>	CountedCompleter<?> c;
5380	>	for (c = firstComplete(); c != null; c = c.nextComplete()) {
5381	>	@SuppressWarnings("unchecked") MapReduceMappingsTask<K,V,U>
5382	>	t = (MapReduceMappingsTask<K,V,U>)c,
5383	>	s = t.rights;
5384	>	while (s != null) {
5385	>	U tr, sr;
5386	>	if ((sr = s.result) != null)
5387	>	t.result = (((tr = t.result) == null) ? sr :
5388	>	reducer.apply(tr, sr));
5389	>	s = t.rights = s.nextRight;
5390	>	}
5391	>	}
5392	>	}
5393		}
5394		}
5395
5396	<	/* ---------------- Serialization Support -------------- */
5396	>	@SuppressWarnings("serial")
5397	>	static final class MapReduceKeysToDoubleTask<K,V>
5398	>	extends BulkTask<K,V,Double> {
5399	>	final ObjectToDouble<? super K> transformer;
5400	>	final DoubleByDoubleToDouble reducer;
5401	>	final double basis;
5402	>	double result;
5403	>	MapReduceKeysToDoubleTask<K,V> rights, nextRight;
5404	>	MapReduceKeysToDoubleTask
5405	>	(BulkTask<K,V,?> p, int b, int i, int f, Node<K,V>[] t,
5406	>	MapReduceKeysToDoubleTask<K,V> nextRight,
5407	>	ObjectToDouble<? super K> transformer,
5408	>	double basis,
5409	>	DoubleByDoubleToDouble reducer) {
5410	>	super(p, b, i, f, t); this.nextRight = nextRight;
5411	>	this.transformer = transformer;
5412	>	this.basis = basis; this.reducer = reducer;
5413	>	}
5414	>	public final Double getRawResult() { return result; }
5415	>	public final void compute() {
5416	>	final ObjectToDouble<? super K> transformer;
5417	>	final DoubleByDoubleToDouble reducer;
5418	>	if ((transformer = this.transformer) != null &&
5419	>	(reducer = this.reducer) != null) {
5420	>	double r = this.basis;
5421	>	for (int i = baseIndex, f, h; batch > 0 &&
5422	>	(h = ((f = baseLimit) + i) >>> 1) > i;) {
5423	>	addToPendingCount(1);
5424	>	(rights = new MapReduceKeysToDoubleTask<K,V>
5425	>	(this, batch >>>= 1, baseLimit = h, f, tab,
5426	>	rights, transformer, r, reducer)).fork();
5427	>	}
5428	>	for (Node<K,V> p; (p = advance()) != null; )
5429	>	r = reducer.apply(r, transformer.apply(p.key));
5430	>	result = r;
5431	>	CountedCompleter<?> c;
5432	>	for (c = firstComplete(); c != null; c = c.nextComplete()) {
5433	>	@SuppressWarnings("unchecked") MapReduceKeysToDoubleTask<K,V>
5434	>	t = (MapReduceKeysToDoubleTask<K,V>)c,
5435	>	s = t.rights;
5436	>	while (s != null) {
5437	>	t.result = reducer.apply(t.result, s.result);
5438	>	s = t.rights = s.nextRight;
5439	>	}
5440	>	}
5441	>	}
5442	>	}
5443	>	}
5444	>
5445	>	@SuppressWarnings("serial")
5446	>	static final class MapReduceValuesToDoubleTask<K,V>
5447	>	extends BulkTask<K,V,Double> {
5448	>	final ObjectToDouble<? super V> transformer;
5449	>	final DoubleByDoubleToDouble reducer;
5450	>	final double basis;
5451	>	double result;
5452	>	MapReduceValuesToDoubleTask<K,V> rights, nextRight;
5453	>	MapReduceValuesToDoubleTask
5454	>	(BulkTask<K,V,?> p, int b, int i, int f, Node<K,V>[] t,
5455	>	MapReduceValuesToDoubleTask<K,V> nextRight,
5456	>	ObjectToDouble<? super V> transformer,
5457	>	double basis,
5458	>	DoubleByDoubleToDouble reducer) {
5459	>	super(p, b, i, f, t); this.nextRight = nextRight;
5460	>	this.transformer = transformer;
5461	>	this.basis = basis; this.reducer = reducer;
5462	>	}
5463	>	public final Double getRawResult() { return result; }
5464	>	public final void compute() {
5465	>	final ObjectToDouble<? super V> transformer;
5466	>	final DoubleByDoubleToDouble reducer;
5467	>	if ((transformer = this.transformer) != null &&
5468	>	(reducer = this.reducer) != null) {
5469	>	double r = this.basis;
5470	>	for (int i = baseIndex, f, h; batch > 0 &&
5471	>	(h = ((f = baseLimit) + i) >>> 1) > i;) {
5472	>	addToPendingCount(1);
5473	>	(rights = new MapReduceValuesToDoubleTask<K,V>
5474	>	(this, batch >>>= 1, baseLimit = h, f, tab,
5475	>	rights, transformer, r, reducer)).fork();
5476	>	}
5477	>	for (Node<K,V> p; (p = advance()) != null; )
5478	>	r = reducer.apply(r, transformer.apply(p.val));
5479	>	result = r;
5480	>	CountedCompleter<?> c;
5481	>	for (c = firstComplete(); c != null; c = c.nextComplete()) {
5482	>	@SuppressWarnings("unchecked") MapReduceValuesToDoubleTask<K,V>
5483	>	t = (MapReduceValuesToDoubleTask<K,V>)c,
5484	>	s = t.rights;
5485	>	while (s != null) {
5486	>	t.result = reducer.apply(t.result, s.result);
5487	>	s = t.rights = s.nextRight;
5488	>	}
5489	>	}
5490	>	}
5491	>	}
5492	>	}
5493	>
5494	>	@SuppressWarnings("serial")
5495	>	static final class MapReduceEntriesToDoubleTask<K,V>
5496	>	extends BulkTask<K,V,Double> {
5497	>	final ObjectToDouble<Map.Entry<K,V>> transformer;
5498	>	final DoubleByDoubleToDouble reducer;
5499	>	final double basis;
5500	>	double result;
5501	>	MapReduceEntriesToDoubleTask<K,V> rights, nextRight;
5502	>	MapReduceEntriesToDoubleTask
5503	>	(BulkTask<K,V,?> p, int b, int i, int f, Node<K,V>[] t,
5504	>	MapReduceEntriesToDoubleTask<K,V> nextRight,
5505	>	ObjectToDouble<Map.Entry<K,V>> transformer,
5506	>	double basis,
5507	>	DoubleByDoubleToDouble reducer) {
5508	>	super(p, b, i, f, t); this.nextRight = nextRight;
5509	>	this.transformer = transformer;
5510	>	this.basis = basis; this.reducer = reducer;
5511	>	}
5512	>	public final Double getRawResult() { return result; }
5513	>	public final void compute() {
5514	>	final ObjectToDouble<Map.Entry<K,V>> transformer;
5515	>	final DoubleByDoubleToDouble reducer;
5516	>	if ((transformer = this.transformer) != null &&
5517	>	(reducer = this.reducer) != null) {
5518	>	double r = this.basis;
5519	>	for (int i = baseIndex, f, h; batch > 0 &&
5520	>	(h = ((f = baseLimit) + i) >>> 1) > i;) {
5521	>	addToPendingCount(1);
5522	>	(rights = new MapReduceEntriesToDoubleTask<K,V>
5523	>	(this, batch >>>= 1, baseLimit = h, f, tab,
5524	>	rights, transformer, r, reducer)).fork();
5525	>	}
5526	>	for (Node<K,V> p; (p = advance()) != null; )
5527	>	r = reducer.apply(r, transformer.apply(p));
5528	>	result = r;
5529	>	CountedCompleter<?> c;
5530	>	for (c = firstComplete(); c != null; c = c.nextComplete()) {
5531	>	@SuppressWarnings("unchecked") MapReduceEntriesToDoubleTask<K,V>
5532	>	t = (MapReduceEntriesToDoubleTask<K,V>)c,
5533	>	s = t.rights;
5534	>	while (s != null) {
5535	>	t.result = reducer.apply(t.result, s.result);
5536	>	s = t.rights = s.nextRight;
5537	>	}
5538	>	}
5539	>	}
5540	>	}
5541	>	}
5542	>
5543	>	@SuppressWarnings("serial")
5544	>	static final class MapReduceMappingsToDoubleTask<K,V>
5545	>	extends BulkTask<K,V,Double> {
5546	>	final ObjectByObjectToDouble<? super K, ? super V> transformer;
5547	>	final DoubleByDoubleToDouble reducer;
5548	>	final double basis;
5549	>	double result;
5550	>	MapReduceMappingsToDoubleTask<K,V> rights, nextRight;
5551	>	MapReduceMappingsToDoubleTask
5552	>	(BulkTask<K,V,?> p, int b, int i, int f, Node<K,V>[] t,
5553	>	MapReduceMappingsToDoubleTask<K,V> nextRight,
5554	>	ObjectByObjectToDouble<? super K, ? super V> transformer,
5555	>	double basis,
5556	>	DoubleByDoubleToDouble reducer) {
5557	>	super(p, b, i, f, t); this.nextRight = nextRight;
5558	>	this.transformer = transformer;
5559	>	this.basis = basis; this.reducer = reducer;
5560	>	}
5561	>	public final Double getRawResult() { return result; }
5562	>	public final void compute() {
5563	>	final ObjectByObjectToDouble<? super K, ? super V> transformer;
5564	>	final DoubleByDoubleToDouble reducer;
5565	>	if ((transformer = this.transformer) != null &&
5566	>	(reducer = this.reducer) != null) {
5567	>	double r = this.basis;
5568	>	for (int i = baseIndex, f, h; batch > 0 &&
5569	>	(h = ((f = baseLimit) + i) >>> 1) > i;) {
5570	>	addToPendingCount(1);
5571	>	(rights = new MapReduceMappingsToDoubleTask<K,V>
5572	>	(this, batch >>>= 1, baseLimit = h, f, tab,
5573	>	rights, transformer, r, reducer)).fork();
5574	>	}
5575	>	for (Node<K,V> p; (p = advance()) != null; )
5576	>	r = reducer.apply(r, transformer.apply(p.key, p.val));
5577	>	result = r;
5578	>	CountedCompleter<?> c;
5579	>	for (c = firstComplete(); c != null; c = c.nextComplete()) {
5580	>	@SuppressWarnings("unchecked") MapReduceMappingsToDoubleTask<K,V>
5581	>	t = (MapReduceMappingsToDoubleTask<K,V>)c,
5582	>	s = t.rights;
5583	>	while (s != null) {
5584	>	t.result = reducer.apply(t.result, s.result);
5585	>	s = t.rights = s.nextRight;
5586	>	}
5587	>	}
5588	>	}
5589	>	}
5590	>	}
5591	>
5592	>	@SuppressWarnings("serial")
5593	>	static final class MapReduceKeysToLongTask<K,V>
5594	>	extends BulkTask<K,V,Long> {
5595	>	final ObjectToLong<? super K> transformer;
5596	>	final LongByLongToLong reducer;
5597	>	final long basis;
5598	>	long result;
5599	>	MapReduceKeysToLongTask<K,V> rights, nextRight;
5600	>	MapReduceKeysToLongTask
5601	>	(BulkTask<K,V,?> p, int b, int i, int f, Node<K,V>[] t,
5602	>	MapReduceKeysToLongTask<K,V> nextRight,
5603	>	ObjectToLong<? super K> transformer,
5604	>	long basis,
5605	>	LongByLongToLong reducer) {
5606	>	super(p, b, i, f, t); this.nextRight = nextRight;
5607	>	this.transformer = transformer;
5608	>	this.basis = basis; this.reducer = reducer;
5609	>	}
5610	>	public final Long getRawResult() { return result; }
5611	>	public final void compute() {
5612	>	final ObjectToLong<? super K> transformer;
5613	>	final LongByLongToLong reducer;
5614	>	if ((transformer = this.transformer) != null &&
5615	>	(reducer = this.reducer) != null) {
5616	>	long r = this.basis;
5617	>	for (int i = baseIndex, f, h; batch > 0 &&
5618	>	(h = ((f = baseLimit) + i) >>> 1) > i;) {
5619	>	addToPendingCount(1);
5620	>	(rights = new MapReduceKeysToLongTask<K,V>
5621	>	(this, batch >>>= 1, baseLimit = h, f, tab,
5622	>	rights, transformer, r, reducer)).fork();
5623	>	}
5624	>	for (Node<K,V> p; (p = advance()) != null; )
5625	>	r = reducer.apply(r, transformer.apply(p.key));
5626	>	result = r;
5627	>	CountedCompleter<?> c;
5628	>	for (c = firstComplete(); c != null; c = c.nextComplete()) {
5629	>	@SuppressWarnings("unchecked") MapReduceKeysToLongTask<K,V>
5630	>	t = (MapReduceKeysToLongTask<K,V>)c,
5631	>	s = t.rights;
5632	>	while (s != null) {
5633	>	t.result = reducer.apply(t.result, s.result);
5634	>	s = t.rights = s.nextRight;
5635	>	}
5636	>	}
5637	>	}
5638	>	}
5639	>	}
5640	>
5641	>	@SuppressWarnings("serial")
5642	>	static final class MapReduceValuesToLongTask<K,V>
5643	>	extends BulkTask<K,V,Long> {
5644	>	final ObjectToLong<? super V> transformer;
5645	>	final LongByLongToLong reducer;
5646	>	final long basis;
5647	>	long result;
5648	>	MapReduceValuesToLongTask<K,V> rights, nextRight;
5649	>	MapReduceValuesToLongTask
5650	>	(BulkTask<K,V,?> p, int b, int i, int f, Node<K,V>[] t,
5651	>	MapReduceValuesToLongTask<K,V> nextRight,
5652	>	ObjectToLong<? super V> transformer,
5653	>	long basis,
5654	>	LongByLongToLong reducer) {
5655	>	super(p, b, i, f, t); this.nextRight = nextRight;
5656	>	this.transformer = transformer;
5657	>	this.basis = basis; this.reducer = reducer;
5658	>	}
5659	>	public final Long getRawResult() { return result; }
5660	>	public final void compute() {
5661	>	final ObjectToLong<? super V> transformer;
5662	>	final LongByLongToLong reducer;
5663	>	if ((transformer = this.transformer) != null &&
5664	>	(reducer = this.reducer) != null) {
5665	>	long r = this.basis;
5666	>	for (int i = baseIndex, f, h; batch > 0 &&
5667	>	(h = ((f = baseLimit) + i) >>> 1) > i;) {
5668	>	addToPendingCount(1);
5669	>	(rights = new MapReduceValuesToLongTask<K,V>
5670	>	(this, batch >>>= 1, baseLimit = h, f, tab,
5671	>	rights, transformer, r, reducer)).fork();
5672	>	}
5673	>	for (Node<K,V> p; (p = advance()) != null; )
5674	>	r = reducer.apply(r, transformer.apply(p.val));
5675	>	result = r;
5676	>	CountedCompleter<?> c;
5677	>	for (c = firstComplete(); c != null; c = c.nextComplete()) {
5678	>	@SuppressWarnings("unchecked") MapReduceValuesToLongTask<K,V>
5679	>	t = (MapReduceValuesToLongTask<K,V>)c,
5680	>	s = t.rights;
5681	>	while (s != null) {
5682	>	t.result = reducer.apply(t.result, s.result);
5683	>	s = t.rights = s.nextRight;
5684	>	}
5685	>	}
5686	>	}
5687	>	}
5688	>	}
5689	>
5690	>	@SuppressWarnings("serial")
5691	>	static final class MapReduceEntriesToLongTask<K,V>
5692	>	extends BulkTask<K,V,Long> {
5693	>	final ObjectToLong<Map.Entry<K,V>> transformer;
5694	>	final LongByLongToLong reducer;
5695	>	final long basis;
5696	>	long result;
5697	>	MapReduceEntriesToLongTask<K,V> rights, nextRight;
5698	>	MapReduceEntriesToLongTask
5699	>	(BulkTask<K,V,?> p, int b, int i, int f, Node<K,V>[] t,
5700	>	MapReduceEntriesToLongTask<K,V> nextRight,
5701	>	ObjectToLong<Map.Entry<K,V>> transformer,
5702	>	long basis,
5703	>	LongByLongToLong reducer) {
5704	>	super(p, b, i, f, t); this.nextRight = nextRight;
5705	>	this.transformer = transformer;
5706	>	this.basis = basis; this.reducer = reducer;
5707	>	}
5708	>	public final Long getRawResult() { return result; }
5709	>	public final void compute() {
5710	>	final ObjectToLong<Map.Entry<K,V>> transformer;
5711	>	final LongByLongToLong reducer;
5712	>	if ((transformer = this.transformer) != null &&
5713	>	(reducer = this.reducer) != null) {
5714	>	long r = this.basis;
5715	>	for (int i = baseIndex, f, h; batch > 0 &&
5716	>	(h = ((f = baseLimit) + i) >>> 1) > i;) {
5717	>	addToPendingCount(1);
5718	>	(rights = new MapReduceEntriesToLongTask<K,V>
5719	>	(this, batch >>>= 1, baseLimit = h, f, tab,
5720	>	rights, transformer, r, reducer)).fork();
5721	>	}
5722	>	for (Node<K,V> p; (p = advance()) != null; )
5723	>	r = reducer.apply(r, transformer.apply(p));
5724	>	result = r;
5725	>	CountedCompleter<?> c;
5726	>	for (c = firstComplete(); c != null; c = c.nextComplete()) {
5727	>	@SuppressWarnings("unchecked") MapReduceEntriesToLongTask<K,V>
5728	>	t = (MapReduceEntriesToLongTask<K,V>)c,
5729	>	s = t.rights;
5730	>	while (s != null) {
5731	>	t.result = reducer.apply(t.result, s.result);
5732	>	s = t.rights = s.nextRight;
5733	>	}
5734	>	}
5735	>	}
5736	>	}
5737	>	}
5738	>
5739	>	@SuppressWarnings("serial")
5740	>	static final class MapReduceMappingsToLongTask<K,V>
5741	>	extends BulkTask<K,V,Long> {
5742	>	final ObjectByObjectToLong<? super K, ? super V> transformer;
5743	>	final LongByLongToLong reducer;
5744	>	final long basis;
5745	>	long result;
5746	>	MapReduceMappingsToLongTask<K,V> rights, nextRight;
5747	>	MapReduceMappingsToLongTask
5748	>	(BulkTask<K,V,?> p, int b, int i, int f, Node<K,V>[] t,
5749	>	MapReduceMappingsToLongTask<K,V> nextRight,
5750	>	ObjectByObjectToLong<? super K, ? super V> transformer,
5751	>	long basis,
5752	>	LongByLongToLong reducer) {
5753	>	super(p, b, i, f, t); this.nextRight = nextRight;
5754	>	this.transformer = transformer;
5755	>	this.basis = basis; this.reducer = reducer;
5756	>	}
5757	>	public final Long getRawResult() { return result; }
5758	>	public final void compute() {
5759	>	final ObjectByObjectToLong<? super K, ? super V> transformer;
5760	>	final LongByLongToLong reducer;
5761	>	if ((transformer = this.transformer) != null &&
5762	>	(reducer = this.reducer) != null) {
5763	>	long r = this.basis;
5764	>	for (int i = baseIndex, f, h; batch > 0 &&
5765	>	(h = ((f = baseLimit) + i) >>> 1) > i;) {
5766	>	addToPendingCount(1);
5767	>	(rights = new MapReduceMappingsToLongTask<K,V>
5768	>	(this, batch >>>= 1, baseLimit = h, f, tab,
5769	>	rights, transformer, r, reducer)).fork();
5770	>	}
5771	>	for (Node<K,V> p; (p = advance()) != null; )
5772	>	r = reducer.apply(r, transformer.apply(p.key, p.val));
5773	>	result = r;
5774	>	CountedCompleter<?> c;
5775	>	for (c = firstComplete(); c != null; c = c.nextComplete()) {
5776	>	@SuppressWarnings("unchecked") MapReduceMappingsToLongTask<K,V>
5777	>	t = (MapReduceMappingsToLongTask<K,V>)c,
5778	>	s = t.rights;
5779	>	while (s != null) {
5780	>	t.result = reducer.apply(t.result, s.result);
5781	>	s = t.rights = s.nextRight;
5782	>	}
5783	>	}
5784	>	}
5785	>	}
5786	>	}
5787	>
5788	>	@SuppressWarnings("serial")
5789	>	static final class MapReduceKeysToIntTask<K,V>
5790	>	extends BulkTask<K,V,Integer> {
5791	>	final ObjectToInt<? super K> transformer;
5792	>	final IntByIntToInt reducer;
5793	>	final int basis;
5794	>	int result;
5795	>	MapReduceKeysToIntTask<K,V> rights, nextRight;
5796	>	MapReduceKeysToIntTask
5797	>	(BulkTask<K,V,?> p, int b, int i, int f, Node<K,V>[] t,
5798	>	MapReduceKeysToIntTask<K,V> nextRight,
5799	>	ObjectToInt<? super K> transformer,
5800	>	int basis,
5801	>	IntByIntToInt reducer) {
5802	>	super(p, b, i, f, t); this.nextRight = nextRight;
5803	>	this.transformer = transformer;
5804	>	this.basis = basis; this.reducer = reducer;
5805	>	}
5806	>	public final Integer getRawResult() { return result; }
5807	>	public final void compute() {
5808	>	final ObjectToInt<? super K> transformer;
5809	>	final IntByIntToInt reducer;
5810	>	if ((transformer = this.transformer) != null &&
5811	>	(reducer = this.reducer) != null) {
5812	>	int r = this.basis;
5813	>	for (int i = baseIndex, f, h; batch > 0 &&
5814	>	(h = ((f = baseLimit) + i) >>> 1) > i;) {
5815	>	addToPendingCount(1);
5816	>	(rights = new MapReduceKeysToIntTask<K,V>
5817	>	(this, batch >>>= 1, baseLimit = h, f, tab,
5818	>	rights, transformer, r, reducer)).fork();
5819	>	}
5820	>	for (Node<K,V> p; (p = advance()) != null; )
5821	>	r = reducer.apply(r, transformer.apply(p.key));
5822	>	result = r;
5823	>	CountedCompleter<?> c;
5824	>	for (c = firstComplete(); c != null; c = c.nextComplete()) {
5825	>	@SuppressWarnings("unchecked") MapReduceKeysToIntTask<K,V>
5826	>	t = (MapReduceKeysToIntTask<K,V>)c,
5827	>	s = t.rights;
5828	>	while (s != null) {
5829	>	t.result = reducer.apply(t.result, s.result);
5830	>	s = t.rights = s.nextRight;
5831	>	}
5832	>	}
5833	>	}
5834	>	}
5835	>	}
5836	>
5837	>	@SuppressWarnings("serial")
5838	>	static final class MapReduceValuesToIntTask<K,V>
5839	>	extends BulkTask<K,V,Integer> {
5840	>	final ObjectToInt<? super V> transformer;
5841	>	final IntByIntToInt reducer;
5842	>	final int basis;
5843	>	int result;
5844	>	MapReduceValuesToIntTask<K,V> rights, nextRight;
5845	>	MapReduceValuesToIntTask
5846	>	(BulkTask<K,V,?> p, int b, int i, int f, Node<K,V>[] t,
5847	>	MapReduceValuesToIntTask<K,V> nextRight,
5848	>	ObjectToInt<? super V> transformer,
5849	>	int basis,
5850	>	IntByIntToInt reducer) {
5851	>	super(p, b, i, f, t); this.nextRight = nextRight;
5852	>	this.transformer = transformer;
5853	>	this.basis = basis; this.reducer = reducer;
5854	>	}
5855	>	public final Integer getRawResult() { return result; }
5856	>	public final void compute() {
5857	>	final ObjectToInt<? super V> transformer;
5858	>	final IntByIntToInt reducer;
5859	>	if ((transformer = this.transformer) != null &&
5860	>	(reducer = this.reducer) != null) {
5861	>	int r = this.basis;
5862	>	for (int i = baseIndex, f, h; batch > 0 &&
5863	>	(h = ((f = baseLimit) + i) >>> 1) > i;) {
5864	>	addToPendingCount(1);
5865	>	(rights = new MapReduceValuesToIntTask<K,V>
5866	>	(this, batch >>>= 1, baseLimit = h, f, tab,
5867	>	rights, transformer, r, reducer)).fork();
5868	>	}
5869	>	for (Node<K,V> p; (p = advance()) != null; )
5870	>	r = reducer.apply(r, transformer.apply(p.val));
5871	>	result = r;
5872	>	CountedCompleter<?> c;
5873	>	for (c = firstComplete(); c != null; c = c.nextComplete()) {
5874	>	@SuppressWarnings("unchecked") MapReduceValuesToIntTask<K,V>
5875	>	t = (MapReduceValuesToIntTask<K,V>)c,
5876	>	s = t.rights;
5877	>	while (s != null) {
5878	>	t.result = reducer.apply(t.result, s.result);
5879	>	s = t.rights = s.nextRight;
5880	>	}
5881	>	}
5882	>	}
5883	>	}
5884	>	}
5885	>
5886	>	@SuppressWarnings("serial")
5887	>	static final class MapReduceEntriesToIntTask<K,V>
5888	>	extends BulkTask<K,V,Integer> {
5889	>	final ObjectToInt<Map.Entry<K,V>> transformer;
5890	>	final IntByIntToInt reducer;
5891	>	final int basis;
5892	>	int result;
5893	>	MapReduceEntriesToIntTask<K,V> rights, nextRight;
5894	>	MapReduceEntriesToIntTask
5895	>	(BulkTask<K,V,?> p, int b, int i, int f, Node<K,V>[] t,
5896	>	MapReduceEntriesToIntTask<K,V> nextRight,
5897	>	ObjectToInt<Map.Entry<K,V>> transformer,
5898	>	int basis,
5899	>	IntByIntToInt reducer) {
5900	>	super(p, b, i, f, t); this.nextRight = nextRight;
5901	>	this.transformer = transformer;
5902	>	this.basis = basis; this.reducer = reducer;
5903	>	}
5904	>	public final Integer getRawResult() { return result; }
5905	>	public final void compute() {
5906	>	final ObjectToInt<Map.Entry<K,V>> transformer;
5907	>	final IntByIntToInt reducer;
5908	>	if ((transformer = this.transformer) != null &&
5909	>	(reducer = this.reducer) != null) {
5910	>	int r = this.basis;
5911	>	for (int i = baseIndex, f, h; batch > 0 &&
5912	>	(h = ((f = baseLimit) + i) >>> 1) > i;) {
5913	>	addToPendingCount(1);
5914	>	(rights = new MapReduceEntriesToIntTask<K,V>
5915	>	(this, batch >>>= 1, baseLimit = h, f, tab,
5916	>	rights, transformer, r, reducer)).fork();
5917	>	}
5918	>	for (Node<K,V> p; (p = advance()) != null; )
5919	>	r = reducer.apply(r, transformer.apply(p));
5920	>	result = r;
5921	>	CountedCompleter<?> c;
5922	>	for (c = firstComplete(); c != null; c = c.nextComplete()) {
5923	>	@SuppressWarnings("unchecked") MapReduceEntriesToIntTask<K,V>
5924	>	t = (MapReduceEntriesToIntTask<K,V>)c,
5925	>	s = t.rights;
5926	>	while (s != null) {
5927	>	t.result = reducer.apply(t.result, s.result);
5928	>	s = t.rights = s.nextRight;
5929	>	}
5930	>	}
5931	>	}
5932	>	}
5933	>	}
5934	>
5935	>	@SuppressWarnings("serial")
5936	>	static final class MapReduceMappingsToIntTask<K,V>
5937	>	extends BulkTask<K,V,Integer> {
5938	>	final ObjectByObjectToInt<? super K, ? super V> transformer;
5939	>	final IntByIntToInt reducer;
5940	>	final int basis;
5941	>	int result;
5942	>	MapReduceMappingsToIntTask<K,V> rights, nextRight;
5943	>	MapReduceMappingsToIntTask
5944	>	(BulkTask<K,V,?> p, int b, int i, int f, Node<K,V>[] t,
5945	>	MapReduceMappingsToIntTask<K,V> nextRight,
5946	>	ObjectByObjectToInt<? super K, ? super V> transformer,
5947	>	int basis,
5948	>	IntByIntToInt reducer) {
5949	>	super(p, b, i, f, t); this.nextRight = nextRight;
5950	>	this.transformer = transformer;
5951	>	this.basis = basis; this.reducer = reducer;
5952	>	}
5953	>	public final Integer getRawResult() { return result; }
5954	>	public final void compute() {
5955	>	final ObjectByObjectToInt<? super K, ? super V> transformer;
5956	>	final IntByIntToInt reducer;
5957	>	if ((transformer = this.transformer) != null &&
5958	>	(reducer = this.reducer) != null) {
5959	>	int r = this.basis;
5960	>	for (int i = baseIndex, f, h; batch > 0 &&
5961	>	(h = ((f = baseLimit) + i) >>> 1) > i;) {
5962	>	addToPendingCount(1);
5963	>	(rights = new MapReduceMappingsToIntTask<K,V>
5964	>	(this, batch >>>= 1, baseLimit = h, f, tab,
5965	>	rights, transformer, r, reducer)).fork();
5966	>	}
5967	>	for (Node<K,V> p; (p = advance()) != null; )
5968	>	r = reducer.apply(r, transformer.apply(p.key, p.val));
5969	>	result = r;
5970	>	CountedCompleter<?> c;
5971	>	for (c = firstComplete(); c != null; c = c.nextComplete()) {
5972	>	@SuppressWarnings("unchecked") MapReduceMappingsToIntTask<K,V>
5973	>	t = (MapReduceMappingsToIntTask<K,V>)c,
5974	>	s = t.rights;
5975	>	while (s != null) {
5976	>	t.result = reducer.apply(t.result, s.result);
5977	>	s = t.rights = s.nextRight;
5978	>	}
5979	>	}
5980	>	}
5981	>	}
5982	>	}
5983	>
5984	>	/* ---------------- Counters -------------- */
5985	>
5986	>	// Adapted from LongAdder and Striped64.
5987	>	// See their internal docs for explanation.
5988	>
5989	>	// A padded cell for distributing counts
5990	>	static final class CounterCell {
5991	>	volatile long p0, p1, p2, p3, p4, p5, p6;
5992	>	volatile long value;
5993	>	volatile long q0, q1, q2, q3, q4, q5, q6;
5994	>	CounterCell(long x) { value = x; }
5995	>	}
5996
5997		/**
5998	<	* Helper class used in previous version, declared for the sake of
5999	<	* serialization compatibility
5998	>	* Holder for the thread-local hash code determining which
5999	>	* CounterCell to use. The code is initialized via the
6000	>	* counterHashCodeGenerator, but may be moved upon collisions.
6001		*/
6002	<	static class Segment<K,V> extends java.util.concurrent.locks.ReentrantLock
6003	<	implements Serializable {
1510	<	private static final long serialVersionUID = 2249069246763182397L;
1511	<	final float loadFactor;
1512	<	Segment(float lf) { this.loadFactor = lf; }
6002	>	static final class CounterHashCode {
6003	>	int code;
6004		}
6005
6006		/**
6007	<	* Saves the state of the {@code ConcurrentHashMapV8} instance to a
1517	<	* stream (i.e., serializes it).
1518	<	* @param s the stream
1519	<	* @serialData
1520	<	* the key (Object) and value (Object)
1521	<	* for each key-value mapping, followed by a null pair.
1522	<	* The key-value mappings are emitted in no particular order.
6007	>	* Generates initial value for per-thread CounterHashCodes.
6008		*/
6009	<	@SuppressWarnings("unchecked")
1525	<	private void writeObject(java.io.ObjectOutputStream s)
1526	<	throws java.io.IOException {
1527	<	if (segments == null) { // for serialization compatibility
1528	<	segments = (Segment<K,V>[])
1529	<	new Segment<?,?>[DEFAULT_CONCURRENCY_LEVEL];
1530	<	for (int i = 0; i < segments.length; ++i)
1531	<	segments[i] = new Segment<K,V>(loadFactor);
1532	<	}
1533	<	s.defaultWriteObject();
1534	<	new HashIterator().writeEntries(s);
1535	<	s.writeObject(null);
1536	<	s.writeObject(null);
1537	<	segments = null; // throw away
1538	<	}
6009	>	static final AtomicInteger counterHashCodeGenerator = new AtomicInteger();
6010
6011		/**
6012	<	* Reconstitutes the instance from a stream (that is, deserializes it).
6013	<	* @param s the stream
6012	>	* Increment for counterHashCodeGenerator. See class ThreadLocal
6013	>	* for explanation.
6014		*/
6015	<	@SuppressWarnings("unchecked")
6016	<	private void readObject(java.io.ObjectInputStream s)
6017	<	throws java.io.IOException, ClassNotFoundException {
6018	<	s.defaultReadObject();
6019	<	// find load factor in a segment, if one exists
6020	<	if (segments != null && segments.length != 0)
6021	<	this.loadFactor = segments[0].loadFactor;
6022	<	else
6023	<	this.loadFactor = DEFAULT_LOAD_FACTOR;
6024	<	this.initCap = DEFAULT_CAPACITY;
6025	<	LongAdder ct = new LongAdder(); // force final field write
6026	<	UNSAFE.putObjectVolatile(this, counterOffset, ct);
6027	<	this.segments = null; // unneeded
6015	>	static final int SEED_INCREMENT = 0x61c88647;
6016	>
6017	>	/**
6018	>	* Per-thread counter hash codes. Shared across all instances.
6019	>	*/
6020	>	static final ThreadLocal<CounterHashCode> threadCounterHashCode =
6021	>	new ThreadLocal<CounterHashCode>();
6022	>
6023	>
6024	>	final long sumCount() {
6025	>	CounterCell[] as = counterCells; CounterCell a;
6026	>	long sum = baseCount;
6027	>	if (as != null) {
6028	>	for (int i = 0; i < as.length; ++i) {
6029	>	if ((a = as[i]) != null)
6030	>	sum += a.value;
6031	>	}
6032	>	}
6033	>	return sum;
6034	>	}
6035
6036	<	// Read the keys and values, and put the mappings in the table
6036	>	// See LongAdder version for explanation
6037	>	private final void fullAddCount(long x, CounterHashCode hc,
6038	>	boolean wasUncontended) {
6039	>	int h;
6040	>	if (hc == null) {
6041	>	hc = new CounterHashCode();
6042	>	int s = counterHashCodeGenerator.addAndGet(SEED_INCREMENT);
6043	>	h = hc.code = (s == 0) ? 1 : s; // Avoid zero
6044	>	threadCounterHashCode.set(hc);
6045	>	}
6046	>	else
6047	>	h = hc.code;
6048	>	boolean collide = false;                // True if last slot nonempty
6049		for (;;) {
6050	<	K key = (K) s.readObject();
6051	<	V value = (V) s.readObject();
6052	<	if (key == null)
6053	<	break;
6054	<	put(key, value);
6050	>	CounterCell[] as; CounterCell a; int n; long v;
6051	>	if ((as = counterCells) != null && (n = as.length) > 0) {
6052	>	if ((a = as[(n - 1) & h]) == null) {
6053	>	if (cellsBusy == 0) {            // Try to attach new Cell
6054	>	CounterCell r = new CounterCell(x); // Optimistic create
6055	>	if (cellsBusy == 0 &&
6056	>	U.compareAndSwapInt(this, CELLSBUSY, 0, 1)) {
6057	>	boolean created = false;
6058	>	try {               // Recheck under lock
6059	>	CounterCell[] rs; int m, j;
6060	>	if ((rs = counterCells) != null &&
6061	>	(m = rs.length) > 0 &&
6062	>	rs[j = (m - 1) & h] == null) {
6063	>	rs[j] = r;
6064	>	created = true;
6065	>	}
6066	>	} finally {
6067	>	cellsBusy = 0;
6068	>	}
6069	>	if (created)
6070	>	break;
6071	>	continue;           // Slot is now non-empty
6072	>	}
6073	>	}
6074	>	collide = false;
6075	>	}
6076	>	else if (!wasUncontended)       // CAS already known to fail
6077	>	wasUncontended = true;      // Continue after rehash
6078	>	else if (U.compareAndSwapLong(a, CELLVALUE, v = a.value, v + x))
6079	>	break;
6080	>	else if (counterCells != as || n >= NCPU)
6081	>	collide = false;            // At max size or stale
6082	>	else if (!collide)
6083	>	collide = true;
6084	>	else if (cellsBusy == 0 &&
6085	>	U.compareAndSwapInt(this, CELLSBUSY, 0, 1)) {
6086	>	try {
6087	>	if (counterCells == as) {// Expand table unless stale
6088	>	CounterCell[] rs = new CounterCell[n << 1];
6089	>	for (int i = 0; i < n; ++i)
6090	>	rs[i] = as[i];
6091	>	counterCells = rs;
6092	>	}
6093	>	} finally {
6094	>	cellsBusy = 0;
6095	>	}
6096	>	collide = false;
6097	>	continue;                   // Retry with expanded table
6098	>	}
6099	>	h ^= h << 13;                   // Rehash
6100	>	h ^= h >>> 17;
6101	>	h ^= h << 5;
6102	>	}
6103	>	else if (cellsBusy == 0 && counterCells == as &&
6104	>	U.compareAndSwapInt(this, CELLSBUSY, 0, 1)) {
6105	>	boolean init = false;
6106	>	try {                           // Initialize table
6107	>	if (counterCells == as) {
6108	>	CounterCell[] rs = new CounterCell[2];
6109	>	rs[h & 1] = new CounterCell(x);
6110	>	counterCells = rs;
6111	>	init = true;
6112	>	}
6113	>	} finally {
6114	>	cellsBusy = 0;
6115	>	}
6116	>	if (init)
6117	>	break;
6118	>	}
6119	>	else if (U.compareAndSwapLong(this, BASECOUNT, v = baseCount, v + x))
6120	>	break;                          // Fall back on using base
6121		}
6122	+	hc.code = h;                            // Record index for next time
6123		}
6124
6125		// Unsafe mechanics
6126	<	private static final sun.misc.Unsafe UNSAFE;
6127	<	private static final long counterOffset;
6128	<	private static final long resizingOffset;
6126	>	private static final sun.misc.Unsafe U;
6127	>	private static final long SIZECTL;
6128	>	private static final long TRANSFERINDEX;
6129	>	private static final long TRANSFERORIGIN;
6130	>	private static final long BASECOUNT;
6131	>	private static final long CELLSBUSY;
6132	>	private static final long CELLVALUE;
6133		private static final long ABASE;
6134		private static final int ASHIFT;
6135
6136		static {
1576	–	int ss;
6137		try {
6138	<	UNSAFE = getUnsafe();
6138	>	U = getUnsafe();
6139		Class<?> k = ConcurrentHashMapV8.class;
6140	<	counterOffset = UNSAFE.objectFieldOffset
6141	<	(k.getDeclaredField("counter"));
6142	<	resizingOffset = UNSAFE.objectFieldOffset
6143	<	(k.getDeclaredField("resizing"));
6144	<	Class<?> sc = Node[].class;
6145	<	ABASE = UNSAFE.arrayBaseOffset(sc);
6146	<	ss = UNSAFE.arrayIndexScale(sc);
6140	>	SIZECTL = U.objectFieldOffset
6141	>	(k.getDeclaredField("sizeCtl"));
6142	>	TRANSFERINDEX = U.objectFieldOffset
6143	>	(k.getDeclaredField("transferIndex"));
6144	>	TRANSFERORIGIN = U.objectFieldOffset
6145	>	(k.getDeclaredField("transferOrigin"));
6146	>	BASECOUNT = U.objectFieldOffset
6147	>	(k.getDeclaredField("baseCount"));
6148	>	CELLSBUSY = U.objectFieldOffset
6149	>	(k.getDeclaredField("cellsBusy"));
6150	>	Class<?> ck = CounterCell.class;
6151	>	CELLVALUE = U.objectFieldOffset
6152	>	(ck.getDeclaredField("value"));
6153	>	Class<?> ak = Node[].class;
6154	>	ABASE = U.arrayBaseOffset(ak);
6155	>	int scale = U.arrayIndexScale(ak);
6156	>	if ((scale & (scale - 1)) != 0)
6157	>	throw new Error("data type scale not a power of two");
6158	>	ASHIFT = 31 - Integer.numberOfLeadingZeros(scale);
6159		} catch (Exception e) {
6160		throw new Error(e);
6161		}
1590	–	if ((ss & (ss-1)) != 0)
1591	–	throw new Error("data type scale not a power of two");
1592	–	ASHIFT = 31 - Integer.numberOfLeadingZeros(ss);
6162		}
6163
6164		/**
#	Line 1602 | Line 6171 | public class ConcurrentHashMapV8<K, V>
6171		private static sun.misc.Unsafe getUnsafe() {
6172		try {
6173		return sun.misc.Unsafe.getUnsafe();
6174	<	} catch (SecurityException se) {
6175	<	try {
6176	<	return java.security.AccessController.doPrivileged
6177	<	(new java.security
6178	<	.PrivilegedExceptionAction<sun.misc.Unsafe>() {
6179	<	public sun.misc.Unsafe run() throws Exception {
6180	<	java.lang.reflect.Field f = sun.misc
6181	<	.Unsafe.class.getDeclaredField("theUnsafe");
6182	<	f.setAccessible(true);
6183	<	return (sun.misc.Unsafe) f.get(null);
6184	<	}});
6185	<	} catch (java.security.PrivilegedActionException e) {
6186	<	throw new RuntimeException("Could not initialize intrinsics",
6187	<	e.getCause());
6188	<	}
6174	>	} catch (SecurityException tryReflectionInstead) {}
6175	>	try {
6176	>	return java.security.AccessController.doPrivileged
6177	>	(new java.security.PrivilegedExceptionAction<sun.misc.Unsafe>() {
6178	>	public sun.misc.Unsafe run() throws Exception {
6179	>	Class<sun.misc.Unsafe> k = sun.misc.Unsafe.class;
6180	>	for (java.lang.reflect.Field f : k.getDeclaredFields()) {
6181	>	f.setAccessible(true);
6182	>	Object x = f.get(null);
6183	>	if (k.isInstance(x))
6184	>	return k.cast(x);
6185	>	}
6186	>	throw new NoSuchFieldError("the Unsafe");
6187	>	}});
6188	>	} catch (java.security.PrivilegedActionException e) {
6189	>	throw new RuntimeException("Could not initialize intrinsics",
6190	>	e.getCause());
6191		}
6192		}
1622	–
6193		}

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