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Revision 1.83 by jsr166, Mon Aug 22 03:42:10 2005 UTC vs.
Revision 1.134 by jsr166, Sun Oct 21 04:07:13 2012 UTC

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1		/*
2		* Written by Doug Lea with assistance from members of JCP JSR-166
3		* Expert Group and released to the public domain, as explained at
4	<	* http://creativecommons.org/licenses/publicdomain
4	>	* http://creativecommons.org/publicdomain/zero/1.0/
5		*/
6
7		package java.util.concurrent;
8	<	import java.util.concurrent.locks.*;
9	<	import java.util.*;
8	>	import java.util.concurrent.atomic.LongAdder;
9	>	import java.util.concurrent.ForkJoinPool;
10	>	import java.util.concurrent.ForkJoinTask;
11	>
12	>	import java.util.Comparator;
13	>	import java.util.Arrays;
14	>	import java.util.Map;
15	>	import java.util.Set;
16	>	import java.util.Collection;
17	>	import java.util.AbstractMap;
18	>	import java.util.AbstractSet;
19	>	import java.util.AbstractCollection;
20	>	import java.util.Hashtable;
21	>	import java.util.HashMap;
22	>	import java.util.Iterator;
23	>	import java.util.Enumeration;
24	>	import java.util.ConcurrentModificationException;
25	>	import java.util.NoSuchElementException;
26	>	import java.util.concurrent.ConcurrentMap;
27	>	import java.util.concurrent.ThreadLocalRandom;
28	>	import java.util.concurrent.locks.LockSupport;
29	>	import java.util.concurrent.locks.AbstractQueuedSynchronizer;
30	>	import java.util.concurrent.atomic.AtomicReference;
31	>
32		import java.io.Serializable;
11	–	import java.io.IOException;
12	–	import java.io.ObjectInputStream;
13	–	import java.io.ObjectOutputStream;
33
34		/**
35		* A hash table supporting full concurrency of retrievals and
36	<	* adjustable expected concurrency for updates. This class obeys the
36	>	* high expected concurrency for updates. This class obeys the
37		* same functional specification as {@link java.util.Hashtable}, and
38		* includes versions of methods corresponding to each method of
39	<	* <tt>Hashtable</tt>. However, even though all operations are
39	>	* {@code Hashtable}. However, even though all operations are
40		* thread-safe, retrieval operations do <em>not</em> entail locking,
41		* and there is <em>not</em> any support for locking the entire table
42		* in a way that prevents all access.  This class is fully
43	<	* interoperable with <tt>Hashtable</tt> in programs that rely on its
43	>	* interoperable with {@code Hashtable} in programs that rely on its
44		* thread safety but not on its synchronization details.
45		*
46	<	* <p> Retrieval operations (including <tt>get</tt>) generally do not
47	<	* block, so may overlap with update operations (including
48	<	* <tt>put</tt> and <tt>remove</tt>). Retrievals reflect the results
49	<	* of the most recently <em>completed</em> update operations holding
50	<	* upon their onset.  For aggregate operations such as <tt>putAll</tt>
51	<	* and <tt>clear</tt>, concurrent retrievals may reflect insertion or
52	<	* removal of only some entries.  Similarly, Iterators and
53	<	* Enumerations return elements reflecting the state of the hash table
54	<	* at some point at or since the creation of the iterator/enumeration.
55	<	* They do <em>not</em> throw {@link ConcurrentModificationException}.
56	<	* However, iterators are designed to be used by only one thread at a time.
46	>	* <p> Retrieval operations (including {@code get}) generally do not
47	>	* block, so may overlap with update operations (including {@code put}
48	>	* and {@code remove}). Retrievals reflect the results of the most
49	>	* recently <em>completed</em> update operations holding upon their
50	>	* onset. (More formally, an update operation for a given key bears a
51	>	* <em>happens-before</em> relation with any (non-null) retrieval for
52	>	* that key reporting the updated value.)  For aggregate operations
53	>	* such as {@code putAll} and {@code clear}, concurrent retrievals may
54	>	* reflect insertion or removal of only some entries.  Similarly,
55	>	* Iterators and Enumerations return elements reflecting the state of
56	>	* the hash table at some point at or since the creation of the
57	>	* iterator/enumeration.  They do <em>not</em> throw {@link
58	>	* ConcurrentModificationException}.  However, iterators are designed
59	>	* to be used by only one thread at a time.  Bear in mind that the
60	>	* results of aggregate status methods including {@code size}, {@code
61	>	* isEmpty}, and {@code containsValue} are typically useful only when
62	>	* a map is not undergoing concurrent updates in other threads.
63	>	* Otherwise the results of these methods reflect transient states
64	>	* that may be adequate for monitoring or estimation purposes, but not
65	>	* for program control.
66		*
67	<	* <p> The allowed concurrency among update operations is guided by
68	<	* the optional <tt>concurrencyLevel</tt> constructor argument
69	<	* (default <tt>16</tt>), which is used as a hint for internal sizing.  The
70	<	* table is internally partitioned to try to permit the indicated
71	<	* number of concurrent updates without contention. Because placement
72	<	* in hash tables is essentially random, the actual concurrency will
73	<	* vary.  Ideally, you should choose a value to accommodate as many
74	<	* threads as will ever concurrently modify the table. Using a
75	<	* significantly higher value than you need can waste space and time,
76	<	* and a significantly lower value can lead to thread contention. But
77	<	* overestimates and underestimates within an order of magnitude do
78	<	* not usually have much noticeable impact. A value of one is
79	<	* appropriate when it is known that only one thread will modify and
80	<	* all others will only read. Also, resizing this or any other kind of
81	<	* hash table is a relatively slow operation, so, when possible, it is
82	<	* a good idea to provide estimates of expected table sizes in
83	<	* constructors.
67	>	* <p> The table is dynamically expanded when there are too many
68	>	* collisions (i.e., keys that have distinct hash codes but fall into
69	>	* the same slot modulo the table size), with the expected average
70	>	* effect of maintaining roughly two bins per mapping (corresponding
71	>	* to a 0.75 load factor threshold for resizing). There may be much
72	>	* variance around this average as mappings are added and removed, but
73	>	* overall, this maintains a commonly accepted time/space tradeoff for
74	>	* hash tables.  However, resizing this or any other kind of hash
75	>	* table may be a relatively slow operation. When possible, it is a
76	>	* good idea to provide a size estimate as an optional {@code
77	>	* initialCapacity} constructor argument. An additional optional
78	>	* {@code loadFactor} constructor argument provides a further means of
79	>	* customizing initial table capacity by specifying the table density
80	>	* to be used in calculating the amount of space to allocate for the
81	>	* given number of elements.  Also, for compatibility with previous
82	>	* versions of this class, constructors may optionally specify an
83	>	* expected {@code concurrencyLevel} as an additional hint for
84	>	* internal sizing.  Note that using many keys with exactly the same
85	>	* {@code hashCode()} is a sure way to slow down performance of any
86	>	* hash table.
87		*
88		* <p>This class and its views and iterators implement all of the
89		* <em>optional</em> methods of the {@link Map} and {@link Iterator}
90		* interfaces.
91		*
92		* <p> Like {@link Hashtable} but unlike {@link HashMap}, this class
93	<	* does <em>not</em> allow <tt>null</tt> to be used as a key or value.
93	>	* does <em>not</em> allow {@code null} to be used as a key or value.
94		*
95		* <p>This class is a member of the
96	<	* <a href="{@docRoot}/../guide/collections/index.html">
96	>	* <a href="{@docRoot}/../technotes/guides/collections/index.html">
97		* Java Collections Framework</a>.
98		*
99	+	* <p><em> During transition to JDK8, this
100	+	* class declares and uses nested functional interfaces with different
101	+	* names but the same forms as those expected for JDK8.<em>
102	+	*
103		* @since 1.5
104		* @author Doug Lea
105		* @param <K> the type of keys maintained by this map
106		* @param <V> the type of mapped values
107		*/
108	<	public class ConcurrentHashMap<K, V> extends AbstractMap<K, V>
109	<	implements ConcurrentMap<K, V>, Serializable {
108	>	public class ConcurrentHashMap<K, V>
109	>	implements ConcurrentMap<K, V>, Serializable {
110		private static final long serialVersionUID = 7249069246763182397L;
111
112	+	/**
113	+	* A partitionable iterator. A Spliterator can be traversed
114	+	* directly, but can also be partitioned (before traversal) by
115	+	* creating another Spliterator that covers a non-overlapping
116	+	* portion of the elements, and so may be amenable to parallel
117	+	* execution.
118	+	*
119	+	* <p> This interface exports a subset of expected JDK8
120	+	* functionality.
121	+	*
122	+	* <p>Sample usage: Here is one (of the several) ways to compute
123	+	* the sum of the values held in a map using the ForkJoin
124	+	* framework. As illustrated here, Spliterators are well suited to
125	+	* designs in which a task repeatedly splits off half its work
126	+	* into forked subtasks until small enough to process directly,
127	+	* and then joins these subtasks. Variants of this style can also
128	+	* be used in completion-based designs.
129	+	*
130	+	* <pre>
131	+	* {@code ConcurrentHashMap<String, Long> m = ...
132	+	* // split as if have 8 * parallelism, for load balance
133	+	* int n = m.size();
134	+	* int p = aForkJoinPool.getParallelism() * 8;
135	+	* int split = (n < p)? n : p;
136	+	* long sum = aForkJoinPool.invoke(new SumValues(m.valueSpliterator(), split, null));
137	+	* // ...
138	+	* static class SumValues extends RecursiveTask<Long> {
139	+	*   final Spliterator<Long> s;
140	+	*   final int split;             // split while > 1
141	+	*   final SumValues nextJoin;    // records forked subtasks to join
142	+	*   SumValues(Spliterator<Long> s, int depth, SumValues nextJoin) {
143	+	*     this.s = s; this.depth = depth; this.nextJoin = nextJoin;
144	+	*   }
145	+	*   public Long compute() {
146	+	*     long sum = 0;
147	+	*     SumValues subtasks = null; // fork subtasks
148	+	*     for (int s = split >>> 1; s > 0; s >>>= 1)
149	+	*       (subtasks = new SumValues(s.split(), s, subtasks)).fork();
150	+	*     while (s.hasNext())        // directly process remaining elements
151	+	*       sum += s.next();
152	+	*     for (SumValues t = subtasks; t != null; t = t.nextJoin)
153	+	*       sum += t.join();         // collect subtask results
154	+	*     return sum;
155	+	*   }
156	+	* }
157	+	* }</pre>
158	+	*/
159	+	public static interface Spliterator<T> extends Iterator<T> {
160	+	/**
161	+	* Returns a Spliterator covering approximately half of the
162	+	* elements, guaranteed not to overlap with those subsequently
163	+	* returned by this Spliterator.  After invoking this method,
164	+	* the current Spliterator will <em>not</em> produce any of
165	+	* the elements of the returned Spliterator, but the two
166	+	* Spliterators together will produce all of the elements that
167	+	* would have been produced by this Spliterator had this
168	+	* method not been called. The exact number of elements
169	+	* produced by the returned Spliterator is not guaranteed, and
170	+	* may be zero (i.e., with {@code hasNext()} reporting {@code
171	+	* false}) if this Spliterator cannot be further split.
172	+	*
173	+	* @return a Spliterator covering approximately half of the
174	+	* elements
175	+	* @throws IllegalStateException if this Spliterator has
176	+	* already commenced traversing elements
177	+	*/
178	+	Spliterator<T> split();
179	+	}
180	+
181		/*
182	<	* The basic strategy is to subdivide the table among Segments,
183	<	* each of which itself is a concurrently readable hash table.
182	>	* Overview:
183	>	*
184	>	* The primary design goal of this hash table is to maintain
185	>	* concurrent readability (typically method get(), but also
186	>	* iterators and related methods) while minimizing update
187	>	* contention. Secondary goals are to keep space consumption about
188	>	* the same or better than java.util.HashMap, and to support high
189	>	* initial insertion rates on an empty table by many threads.
190	>	*
191	>	* Each key-value mapping is held in a Node.  Because Node fields
192	>	* can contain special values, they are defined using plain Object
193	>	* types. Similarly in turn, all internal methods that use them
194	>	* work off Object types. And similarly, so do the internal
195	>	* methods of auxiliary iterator and view classes.  All public
196	>	* generic typed methods relay in/out of these internal methods,
197	>	* supplying null-checks and casts as needed. This also allows
198	>	* many of the public methods to be factored into a smaller number
199	>	* of internal methods (although sadly not so for the five
200	>	* variants of put-related operations). The validation-based
201	>	* approach explained below leads to a lot of code sprawl because
202	>	* retry-control precludes factoring into smaller methods.
203	>	*
204	>	* The table is lazily initialized to a power-of-two size upon the
205	>	* first insertion.  Each bin in the table normally contains a
206	>	* list of Nodes (most often, the list has only zero or one Node).
207	>	* Table accesses require volatile/atomic reads, writes, and
208	>	* CASes.  Because there is no other way to arrange this without
209	>	* adding further indirections, we use intrinsics
210	>	* (sun.misc.Unsafe) operations.  The lists of nodes within bins
211	>	* are always accurately traversable under volatile reads, so long
212	>	* as lookups check hash code and non-nullness of value before
213	>	* checking key equality.
214	>	*
215	>	* We use the top two bits of Node hash fields for control
216	>	* purposes -- they are available anyway because of addressing
217	>	* constraints.  As explained further below, these top bits are
218	>	* used as follows:
219	>	*  00 - Normal
220	>	*  01 - Locked
221	>	*  11 - Locked and may have a thread waiting for lock
222	>	*  10 - Node is a forwarding node
223	>	*
224	>	* The lower 30 bits of each Node's hash field contain a
225	>	* transformation of the key's hash code, except for forwarding
226	>	* nodes, for which the lower bits are zero (and so always have
227	>	* hash field == MOVED).
228	>	*
229	>	* Insertion (via put or its variants) of the first node in an
230	>	* empty bin is performed by just CASing it to the bin.  This is
231	>	* by far the most common case for put operations under most
232	>	* key/hash distributions.  Other update operations (insert,
233	>	* delete, and replace) require locks.  We do not want to waste
234	>	* the space required to associate a distinct lock object with
235	>	* each bin, so instead use the first node of a bin list itself as
236	>	* a lock. Blocking support for these locks relies on the builtin
237	>	* "synchronized" monitors.  However, we also need a tryLock
238	>	* construction, so we overlay these by using bits of the Node
239	>	* hash field for lock control (see above), and so normally use
240	>	* builtin monitors only for blocking and signalling using
241	>	* wait/notifyAll constructions. See Node.tryAwaitLock.
242	>	*
243	>	* Using the first node of a list as a lock does not by itself
244	>	* suffice though: When a node is locked, any update must first
245	>	* validate that it is still the first node after locking it, and
246	>	* retry if not. Because new nodes are always appended to lists,
247	>	* once a node is first in a bin, it remains first until deleted
248	>	* or the bin becomes invalidated (upon resizing).  However,
249	>	* operations that only conditionally update may inspect nodes
250	>	* until the point of update. This is a converse of sorts to the
251	>	* lazy locking technique described by Herlihy & Shavit.
252	>	*
253	>	* The main disadvantage of per-bin locks is that other update
254	>	* operations on other nodes in a bin list protected by the same
255	>	* lock can stall, for example when user equals() or mapping
256	>	* functions take a long time.  However, statistically, under
257	>	* random hash codes, this is not a common problem.  Ideally, the
258	>	* frequency of nodes in bins follows a Poisson distribution
259	>	* (http://en.wikipedia.org/wiki/Poisson_distribution) with a
260	>	* parameter of about 0.5 on average, given the resizing threshold
261	>	* of 0.75, although with a large variance because of resizing
262	>	* granularity. Ignoring variance, the expected occurrences of
263	>	* list size k are (exp(-0.5) * pow(0.5, k) / factorial(k)). The
264	>	* first values are:
265	>	*
266	>	* 0:    0.60653066
267	>	* 1:    0.30326533
268	>	* 2:    0.07581633
269	>	* 3:    0.01263606
270	>	* 4:    0.00157952
271	>	* 5:    0.00015795
272	>	* 6:    0.00001316
273	>	* 7:    0.00000094
274	>	* 8:    0.00000006
275	>	* more: less than 1 in ten million
276	>	*
277	>	* Lock contention probability for two threads accessing distinct
278	>	* elements is roughly 1 / (8 * #elements) under random hashes.
279	>	*
280	>	* Actual hash code distributions encountered in practice
281	>	* sometimes deviate significantly from uniform randomness.  This
282	>	* includes the case when N > (1<<30), so some keys MUST collide.
283	>	* Similarly for dumb or hostile usages in which multiple keys are
284	>	* designed to have identical hash codes. Also, although we guard
285	>	* against the worst effects of this (see method spread), sets of
286	>	* hashes may differ only in bits that do not impact their bin
287	>	* index for a given power-of-two mask.  So we use a secondary
288	>	* strategy that applies when the number of nodes in a bin exceeds
289	>	* a threshold, and at least one of the keys implements
290	>	* Comparable.  These TreeBins use a balanced tree to hold nodes
291	>	* (a specialized form of red-black trees), bounding search time
292	>	* to O(log N).  Each search step in a TreeBin is around twice as
293	>	* slow as in a regular list, but given that N cannot exceed
294	>	* (1<<64) (before running out of addresses) this bounds search
295	>	* steps, lock hold times, etc, to reasonable constants (roughly
296	>	* 100 nodes inspected per operation worst case) so long as keys
297	>	* are Comparable (which is very common -- String, Long, etc).
298	>	* TreeBin nodes (TreeNodes) also maintain the same "next"
299	>	* traversal pointers as regular nodes, so can be traversed in
300	>	* iterators in the same way.
301	>	*
302	>	* The table is resized when occupancy exceeds a percentage
303	>	* threshold (nominally, 0.75, but see below).  Only a single
304	>	* thread performs the resize (using field "sizeCtl", to arrange
305	>	* exclusion), but the table otherwise remains usable for reads
306	>	* and updates. Resizing proceeds by transferring bins, one by
307	>	* one, from the table to the next table.  Because we are using
308	>	* power-of-two expansion, the elements from each bin must either
309	>	* stay at same index, or move with a power of two offset. We
310	>	* eliminate unnecessary node creation by catching cases where old
311	>	* nodes can be reused because their next fields won't change.  On
312	>	* average, only about one-sixth of them need cloning when a table
313	>	* doubles. The nodes they replace will be garbage collectable as
314	>	* soon as they are no longer referenced by any reader thread that
315	>	* may be in the midst of concurrently traversing table.  Upon
316	>	* transfer, the old table bin contains only a special forwarding
317	>	* node (with hash field "MOVED") that contains the next table as
318	>	* its key. On encountering a forwarding node, access and update
319	>	* operations restart, using the new table.
320	>	*
321	>	* Each bin transfer requires its bin lock. However, unlike other
322	>	* cases, a transfer can skip a bin if it fails to acquire its
323	>	* lock, and revisit it later (unless it is a TreeBin). Method
324	>	* rebuild maintains a buffer of TRANSFER_BUFFER_SIZE bins that
325	>	* have been skipped because of failure to acquire a lock, and
326	>	* blocks only if none are available (i.e., only very rarely).
327	>	* The transfer operation must also ensure that all accessible
328	>	* bins in both the old and new table are usable by any traversal.
329	>	* When there are no lock acquisition failures, this is arranged
330	>	* simply by proceeding from the last bin (table.length - 1) up
331	>	* towards the first.  Upon seeing a forwarding node, traversals
332	>	* (see class Iter) arrange to move to the new table
333	>	* without revisiting nodes.  However, when any node is skipped
334	>	* during a transfer, all earlier table bins may have become
335	>	* visible, so are initialized with a reverse-forwarding node back
336	>	* to the old table until the new ones are established. (This
337	>	* sometimes requires transiently locking a forwarding node, which
338	>	* is possible under the above encoding.) These more expensive
339	>	* mechanics trigger only when necessary.
340	>	*
341	>	* The traversal scheme also applies to partial traversals of
342	>	* ranges of bins (via an alternate Traverser constructor)
343	>	* to support partitioned aggregate operations.  Also, read-only
344	>	* operations give up if ever forwarded to a null table, which
345	>	* provides support for shutdown-style clearing, which is also not
346	>	* currently implemented.
347	>	*
348	>	* Lazy table initialization minimizes footprint until first use,
349	>	* and also avoids resizings when the first operation is from a
350	>	* putAll, constructor with map argument, or deserialization.
351	>	* These cases attempt to override the initial capacity settings,
352	>	* but harmlessly fail to take effect in cases of races.
353	>	*
354	>	* The element count is maintained using a LongAdder, which avoids
355	>	* contention on updates but can encounter cache thrashing if read
356	>	* too frequently during concurrent access. To avoid reading so
357	>	* often, resizing is attempted either when a bin lock is
358	>	* contended, or upon adding to a bin already holding two or more
359	>	* nodes (checked before adding in the xIfAbsent methods, after
360	>	* adding in others). Under uniform hash distributions, the
361	>	* probability of this occurring at threshold is around 13%,
362	>	* meaning that only about 1 in 8 puts check threshold (and after
363	>	* resizing, many fewer do so). But this approximation has high
364	>	* variance for small table sizes, so we check on any collision
365	>	* for sizes <= 64. The bulk putAll operation further reduces
366	>	* contention by only committing count updates upon these size
367	>	* checks.
368	>	*
369	>	* Maintaining API and serialization compatibility with previous
370	>	* versions of this class introduces several oddities. Mainly: We
371	>	* leave untouched but unused constructor arguments refering to
372	>	* concurrencyLevel. We accept a loadFactor constructor argument,
373	>	* but apply it only to initial table capacity (which is the only
374	>	* time that we can guarantee to honor it.) We also declare an
375	>	* unused "Segment" class that is instantiated in minimal form
376	>	* only when serializing.
377		*/
378
379		/* ---------------- Constants -------------- */
380
381		/**
382	<	* The default initial capacity for this table,
383	<	* used when not otherwise specified in a constructor.
382	>	* The largest possible table capacity.  This value must be
383	>	* exactly 1<<30 to stay within Java array allocation and indexing
384	>	* bounds for power of two table sizes, and is further required
385	>	* because the top two bits of 32bit hash fields are used for
386	>	* control purposes.
387		*/
388	<	static final int DEFAULT_INITIAL_CAPACITY = 16;
388	>	private static final int MAXIMUM_CAPACITY = 1 << 30;
389
390		/**
391	<	* The default load factor for this table, used when not
392	<	* otherwise specified in a constructor.
391	>	* The default initial table capacity.  Must be a power of 2
392	>	* (i.e., at least 1) and at most MAXIMUM_CAPACITY.
393		*/
394	<	static final float DEFAULT_LOAD_FACTOR = 0.75f;
394	>	private static final int DEFAULT_CAPACITY = 16;
395
396		/**
397	<	* The default concurrency level for this table, used when not
398	<	* otherwise specified in a constructor.
397	>	* The largest possible (non-power of two) array size.
398	>	* Needed by toArray and related methods.
399		*/
400	<	static final int DEFAULT_CONCURRENCY_LEVEL = 16;
400	>	static final int MAX_ARRAY_SIZE = Integer.MAX_VALUE - 8;
401
402		/**
403	<	* The maximum capacity, used if a higher value is implicitly
404	<	* specified by either of the constructors with arguments.  MUST
105	<	* be a power of two <= 1<<30 to ensure that entries are indexable
106	<	* using ints.
403	>	* The default concurrency level for this table. Unused but
404	>	* defined for compatibility with previous versions of this class.
405		*/
406	<	static final int MAXIMUM_CAPACITY = 1 << 30;
406	>	private static final int DEFAULT_CONCURRENCY_LEVEL = 16;
407
408		/**
409	<	* The maximum number of segments to allow; used to bound
410	<	* constructor arguments.
409	>	* The load factor for this table. Overrides of this value in
410	>	* constructors affect only the initial table capacity.  The
411	>	* actual floating point value isn't normally used -- it is
412	>	* simpler to use expressions such as {@code n - (n >>> 2)} for
413	>	* the associated resizing threshold.
414		*/
415	<	static final int MAX_SEGMENTS = 1 << 16; // slightly conservative
415	>	private static final float LOAD_FACTOR = 0.75f;
416
417		/**
418	<	* Number of unsynchronized retries in size and containsValue
419	<	* methods before resorting to locking. This is used to avoid
420	<	* unbounded retries if tables undergo continuous modification
421	<	* which would make it impossible to obtain an accurate result.
418	>	* The buffer size for skipped bins during transfers. The
419	>	* value is arbitrary but should be large enough to avoid
420	>	* most locking stalls during resizes.
421	>	*/
422	>	private static final int TRANSFER_BUFFER_SIZE = 32;
423	>
424	>	/**
425	>	* The bin count threshold for using a tree rather than list for a
426	>	* bin.  The value reflects the approximate break-even point for
427	>	* using tree-based operations.
428	>	*/
429	>	private static final int TREE_THRESHOLD = 8;
430	>
431	>	/*
432	>	* Encodings for special uses of Node hash fields. See above for
433	>	* explanation.
434		*/
435	<	static final int RETRIES_BEFORE_LOCK = 2;
435	>	static final int MOVED     = 0x80000000; // hash field for forwarding nodes
436	>	static final int LOCKED    = 0x40000000; // set/tested only as a bit
437	>	static final int WAITING   = 0xc0000000; // both bits set/tested together
438	>	static final int HASH_BITS = 0x3fffffff; // usable bits of normal node hash
439
440		/* ---------------- Fields -------------- */
441
442		/**
443	<	* Mask value for indexing into segments. The upper bits of a
444	<	* key's hash code are used to choose the segment.
443	>	* The array of bins. Lazily initialized upon first insertion.
444	>	* Size is always a power of two. Accessed directly by iterators.
445		*/
446	<	final int segmentMask;
446	>	transient volatile Node[] table;
447
448		/**
449	<	* Shift value for indexing within segments.
449	>	* The counter maintaining number of elements.
450		*/
451	<	final int segmentShift;
451	>	private transient final LongAdder counter;
452
453		/**
454	<	* The segments, each of which is a specialized hash table
455	<	*/
456	<	final Segment<K,V>[] segments;
454	>	* Table initialization and resizing control.  When negative, the
455	>	* table is being initialized or resized. Otherwise, when table is
456	>	* null, holds the initial table size to use upon creation, or 0
457	>	* for default. After initialization, holds the next element count
458	>	* value upon which to resize the table.
459	>	*/
460	>	private transient volatile int sizeCtl;
461	>
462	>	// views
463	>	private transient KeySet<K,V> keySet;
464	>	private transient Values<K,V> values;
465	>	private transient EntrySet<K,V> entrySet;
466
467	<	transient Set<K> keySet;
468	<	transient Set<Map.Entry<K,V>> entrySet;
144	<	transient Collection<V> values;
467	>	/** For serialization compatibility. Null unless serialized; see below */
468	>	private Segment<K,V>[] segments;
469
470	<	/* ---------------- Small Utilities -------------- */
470	>	/* ---------------- Table element access -------------- */
471
472	<	/**
473	<	* Returns a hash code for non-null Object x.
474	<	* Uses the same hash code spreader as most other java.util hash tables.
475	<	* @param x the object serving as a key
476	<	* @return the hash code
472	>	/*
473	>	* Volatile access methods are used for table elements as well as
474	>	* elements of in-progress next table while resizing.  Uses are
475	>	* null checked by callers, and implicitly bounds-checked, relying
476	>	* on the invariants that tab arrays have non-zero size, and all
477	>	* indices are masked with (tab.length - 1) which is never
478	>	* negative and always less than length. Note that, to be correct
479	>	* wrt arbitrary concurrency errors by users, bounds checks must
480	>	* operate on local variables, which accounts for some odd-looking
481	>	* inline assignments below.
482		*/
483	<	static int hash(Object x) {
484	<	int h = x.hashCode();
485	<	h += ~(h << 9);
157	<	h ^=  (h >>> 14);
158	<	h +=  (h << 4);
159	<	h ^=  (h >>> 10);
160	<	return h;
483	>
484	>	static final Node tabAt(Node[] tab, int i) { // used by Iter
485	>	return (Node)UNSAFE.getObjectVolatile(tab, ((long)i<<ASHIFT)+ABASE);
486		}
487
488	<	/**
489	<	* Returns the segment that should be used for key with given hash
165	<	* @param hash the hash code for the key
166	<	* @return the segment
167	<	*/
168	<	final Segment<K,V> segmentFor(int hash) {
169	<	return segments[(hash >>> segmentShift) & segmentMask];
488	>	private static final boolean casTabAt(Node[] tab, int i, Node c, Node v) {
489	>	return UNSAFE.compareAndSwapObject(tab, ((long)i<<ASHIFT)+ABASE, c, v);
490		}
491
492	<	/* ---------------- Inner Classes -------------- */
492	>	private static final void setTabAt(Node[] tab, int i, Node v) {
493	>	UNSAFE.putObjectVolatile(tab, ((long)i<<ASHIFT)+ABASE, v);
494	>	}
495	>
496	>	/* ---------------- Nodes -------------- */
497
498		/**
499	<	* ConcurrentHashMap list entry. Note that this is never exported
500	<	* out as a user-visible Map.Entry.
501	<	*
502	<	* Because the value field is volatile, not final, it is legal wrt
503	<	* the Java Memory Model for an unsynchronized reader to see null
504	<	* instead of initial value when read via a data race.  Although a
505	<	* reordering leading to this is not likely to ever actually
506	<	* occur, the Segment.readValueUnderLock method is used as a
507	<	* backup in case a null (pre-initialized) value is ever seen in
508	<	* an unsynchronized access method.
509	<	*/
510	<	static final class HashEntry<K,V> {
511	<	final K key;
512	<	final int hash;
189	<	volatile V value;
190	<	final HashEntry<K,V> next;
499	>	* Key-value entry. Note that this is never exported out as a
500	>	* user-visible Map.Entry (see MapEntry below). Nodes with a hash
501	>	* field of MOVED are special, and do not contain user keys or
502	>	* values.  Otherwise, keys are never null, and null val fields
503	>	* indicate that a node is in the process of being deleted or
504	>	* created. For purposes of read-only access, a key may be read
505	>	* before a val, but can only be used after checking val to be
506	>	* non-null.
507	>	*/
508	>	static class Node {
509	>	volatile int hash;
510	>	final Object key;
511	>	volatile Object val;
512	>	volatile Node next;
513
514	<	HashEntry(K key, int hash, HashEntry<K,V> next, V value) {
193	<	this.key = key;
514	>	Node(int hash, Object key, Object val, Node next) {
515		this.hash = hash;
516	+	this.key = key;
517	+	this.val = val;
518		this.next = next;
196	–	this.value = value;
519		}
520
521	<	@SuppressWarnings("unchecked")
522	<	static final <K,V> HashEntry<K,V>[] newArray(int i) {
523	<	return new HashEntry[i];
524	<	}
203	<	}
204	<
205	<	/**
206	<	* Segments are specialized versions of hash tables.  This
207	<	* subclasses from ReentrantLock opportunistically, just to
208	<	* simplify some locking and avoid separate construction.
209	<	*/
210	<	static final class Segment<K,V> extends ReentrantLock implements Serializable {
211	<	/*
212	<	* Segments maintain a table of entry lists that are ALWAYS
213	<	* kept in a consistent state, so can be read without locking.
214	<	* Next fields of nodes are immutable (final).  All list
215	<	* additions are performed at the front of each bin. This
216	<	* makes it easy to check changes, and also fast to traverse.
217	<	* When nodes would otherwise be changed, new nodes are
218	<	* created to replace them. This works well for hash tables
219	<	* since the bin lists tend to be short. (The average length
220	<	* is less than two for the default load factor threshold.)
221	<	*
222	<	* Read operations can thus proceed without locking, but rely
223	<	* on selected uses of volatiles to ensure that completed
224	<	* write operations performed by other threads are
225	<	* noticed. For most purposes, the "count" field, tracking the
226	<	* number of elements, serves as that volatile variable
227	<	* ensuring visibility.  This is convenient because this field
228	<	* needs to be read in many read operations anyway:
229	<	*
230	<	*   - All (unsynchronized) read operations must first read the
231	<	*     "count" field, and should not look at table entries if
232	<	*     it is 0.
233	<	*
234	<	*   - All (synchronized) write operations should write to
235	<	*     the "count" field after structurally changing any bin.
236	<	*     The operations must not take any action that could even
237	<	*     momentarily cause a concurrent read operation to see
238	<	*     inconsistent data. This is made easier by the nature of
239	<	*     the read operations in Map. For example, no operation
240	<	*     can reveal that the table has grown but the threshold
241	<	*     has not yet been updated, so there are no atomicity
242	<	*     requirements for this with respect to reads.
243	<	*
244	<	* As a guide, all critical volatile reads and writes to the
245	<	* count field are marked in code comments.
246	<	*/
521	>	/** CompareAndSet the hash field */
522	>	final boolean casHash(int cmp, int val) {
523	>	return UNSAFE.compareAndSwapInt(this, hashOffset, cmp, val);
524	>	}
525
526	<	private static final long serialVersionUID = 2249069246763182397L;
526	>	/** The number of spins before blocking for a lock */
527	>	static final int MAX_SPINS =
528	>	Runtime.getRuntime().availableProcessors() > 1 ? 64 : 1;
529
530		/**
531	<	* The number of elements in this segment's region.
531	>	* Spins a while if LOCKED bit set and this node is the first
532	>	* of its bin, and then sets WAITING bits on hash field and
533	>	* blocks (once) if they are still set.  It is OK for this
534	>	* method to return even if lock is not available upon exit,
535	>	* which enables these simple single-wait mechanics.
536	>	*
537	>	* The corresponding signalling operation is performed within
538	>	* callers: Upon detecting that WAITING has been set when
539	>	* unlocking lock (via a failed CAS from non-waiting LOCKED
540	>	* state), unlockers acquire the sync lock and perform a
541	>	* notifyAll.
542	>	*
543	>	* The initial sanity check on tab and bounds is not currently
544	>	* necessary in the only usages of this method, but enables
545	>	* use in other future contexts.
546		*/
547	<	transient volatile int count;
547	>	final void tryAwaitLock(Node[] tab, int i) {
548	>	if (tab != null && i >= 0 && i < tab.length) { // sanity check
549	>	int r = ThreadLocalRandom.current().nextInt(); // randomize spins
550	>	int spins = MAX_SPINS, h;
551	>	while (tabAt(tab, i) == this && ((h = hash) & LOCKED) != 0) {
552	>	if (spins >= 0) {
553	>	r ^= r << 1; r ^= r >>> 3; r ^= r << 10; // xorshift
554	>	if (r >= 0 && --spins == 0)
555	>	Thread.yield();  // yield before block
556	>	}
557	>	else if (casHash(h, h | WAITING)) {
558	>	synchronized (this) {
559	>	if (tabAt(tab, i) == this &&
560	>	(hash & WAITING) == WAITING) {
561	>	try {
562	>	wait();
563	>	} catch (InterruptedException ie) {
564	>	Thread.currentThread().interrupt();
565	>	}
566	>	}
567	>	else
568	>	notifyAll(); // possibly won race vs signaller
569	>	}
570	>	break;
571	>	}
572	>	}
573	>	}
574	>	}
575
576	<	/**
577	<	* Number of updates that alter the size of the table. This is
578	<	* used during bulk-read methods to make sure they see a
258	<	* consistent snapshot: If modCounts change during a traversal
259	<	* of segments computing size or checking containsValue, then
260	<	* we might have an inconsistent view of state so (usually)
261	<	* must retry.
262	<	*/
263	<	transient int modCount;
576	>	// Unsafe mechanics for casHash
577	>	private static final sun.misc.Unsafe UNSAFE;
578	>	private static final long hashOffset;
579
580	<	/**
581	<	* The table is rehashed when its size exceeds this threshold.
582	<	* (The value of this field is always <tt>(int)(capacity *
583	<	* loadFactor)</tt>.)
584	<	*/
585	<	transient int threshold;
580	>	static {
581	>	try {
582	>	UNSAFE = sun.misc.Unsafe.getUnsafe();
583	>	Class<?> k = Node.class;
584	>	hashOffset = UNSAFE.objectFieldOffset
585	>	(k.getDeclaredField("hash"));
586	>	} catch (Exception e) {
587	>	throw new Error(e);
588	>	}
589	>	}
590	>	}
591
592	<	/**
273	<	* The per-segment table.
274	<	*/
275	<	transient volatile HashEntry<K,V>[] table;
592	>	/* ---------------- TreeBins -------------- */
593
594	<	/**
595	<	* The load factor for the hash table.  Even though this value
596	<	* is same for all segments, it is replicated to avoid needing
597	<	* links to outer object.
598	<	* @serial
599	<	*/
600	<	final float loadFactor;
594	>	/**
595	>	* Nodes for use in TreeBins
596	>	*/
597	>	static final class TreeNode extends Node {
598	>	TreeNode parent;  // red-black tree links
599	>	TreeNode left;
600	>	TreeNode right;
601	>	TreeNode prev;    // needed to unlink next upon deletion
602	>	boolean red;
603	>
604	>	TreeNode(int hash, Object key, Object val, Node next, TreeNode parent) {
605	>	super(hash, key, val, next);
606	>	this.parent = parent;
607	>	}
608	>	}
609
610	<	Segment(int initialCapacity, float lf) {
611	<	loadFactor = lf;
612	<	setTable(HashEntry.<K,V>newArray(initialCapacity));
610	>	/**
611	>	* A specialized form of red-black tree for use in bins
612	>	* whose size exceeds a threshold.
613	>	*
614	>	* TreeBins use a special form of comparison for search and
615	>	* related operations (which is the main reason we cannot use
616	>	* existing collections such as TreeMaps). TreeBins contain
617	>	* Comparable elements, but may contain others, as well as
618	>	* elements that are Comparable but not necessarily Comparable<T>
619	>	* for the same T, so we cannot invoke compareTo among them. To
620	>	* handle this, the tree is ordered primarily by hash value, then
621	>	* by getClass().getName() order, and then by Comparator order
622	>	* among elements of the same class.  On lookup at a node, if
623	>	* elements are not comparable or compare as 0, both left and
624	>	* right children may need to be searched in the case of tied hash
625	>	* values. (This corresponds to the full list search that would be
626	>	* necessary if all elements were non-Comparable and had tied
627	>	* hashes.)  The red-black balancing code is updated from
628	>	* pre-jdk-collections
629	>	* (http://gee.cs.oswego.edu/dl/classes/collections/RBCell.java)
630	>	* based in turn on Cormen, Leiserson, and Rivest "Introduction to
631	>	* Algorithms" (CLR).
632	>	*
633	>	* TreeBins also maintain a separate locking discipline than
634	>	* regular bins. Because they are forwarded via special MOVED
635	>	* nodes at bin heads (which can never change once established),
636	>	* we cannot use those nodes as locks. Instead, TreeBin
637	>	* extends AbstractQueuedSynchronizer to support a simple form of
638	>	* read-write lock. For update operations and table validation,
639	>	* the exclusive form of lock behaves in the same way as bin-head
640	>	* locks. However, lookups use shared read-lock mechanics to allow
641	>	* multiple readers in the absence of writers.  Additionally,
642	>	* these lookups do not ever block: While the lock is not
643	>	* available, they proceed along the slow traversal path (via
644	>	* next-pointers) until the lock becomes available or the list is
645	>	* exhausted, whichever comes first. (These cases are not fast,
646	>	* but maximize aggregate expected throughput.)  The AQS mechanics
647	>	* for doing this are straightforward.  The lock state is held as
648	>	* AQS getState().  Read counts are negative; the write count (1)
649	>	* is positive.  There are no signalling preferences among readers
650	>	* and writers. Since we don't need to export full Lock API, we
651	>	* just override the minimal AQS methods and use them directly.
652	>	*/
653	>	static final class TreeBin extends AbstractQueuedSynchronizer {
654	>	private static final long serialVersionUID = 2249069246763182397L;
655	>	transient TreeNode root;  // root of tree
656	>	transient TreeNode first; // head of next-pointer list
657	>
658	>	/* AQS overrides */
659	>	public final boolean isHeldExclusively() { return getState() > 0; }
660	>	public final boolean tryAcquire(int ignore) {
661	>	if (compareAndSetState(0, 1)) {
662	>	setExclusiveOwnerThread(Thread.currentThread());
663	>	return true;
664	>	}
665	>	return false;
666	>	}
667	>	public final boolean tryRelease(int ignore) {
668	>	setExclusiveOwnerThread(null);
669	>	setState(0);
670	>	return true;
671	>	}
672	>	public final int tryAcquireShared(int ignore) {
673	>	for (int c;;) {
674	>	if ((c = getState()) > 0)
675	>	return -1;
676	>	if (compareAndSetState(c, c -1))
677	>	return 1;
678	>	}
679	>	}
680	>	public final boolean tryReleaseShared(int ignore) {
681	>	int c;
682	>	do {} while (!compareAndSetState(c = getState(), c + 1));
683	>	return c == -1;
684	>	}
685	>
686	>	/** From CLR */
687	>	private void rotateLeft(TreeNode p) {
688	>	if (p != null) {
689	>	TreeNode r = p.right, pp, rl;
690	>	if ((rl = p.right = r.left) != null)
691	>	rl.parent = p;
692	>	if ((pp = r.parent = p.parent) == null)
693	>	root = r;
694	>	else if (pp.left == p)
695	>	pp.left = r;
696	>	else
697	>	pp.right = r;
698	>	r.left = p;
699	>	p.parent = r;
700	>	}
701		}
702
703	<	@SuppressWarnings("unchecked")
704	<	static final <K,V> Segment<K,V>[] newArray(int i) {
705	<	return new Segment[i];
703	>	/** From CLR */
704	>	private void rotateRight(TreeNode p) {
705	>	if (p != null) {
706	>	TreeNode l = p.left, pp, lr;
707	>	if ((lr = p.left = l.right) != null)
708	>	lr.parent = p;
709	>	if ((pp = l.parent = p.parent) == null)
710	>	root = l;
711	>	else if (pp.right == p)
712	>	pp.right = l;
713	>	else
714	>	pp.left = l;
715	>	l.right = p;
716	>	p.parent = l;
717	>	}
718		}
719
720		/**
721	<	* Sets table to new HashEntry array.
722	<	* Call only while holding lock or in constructor.
721	>	* Returns the TreeNode (or null if not found) for the given key
722	>	* starting at given root.
723		*/
724	<	void setTable(HashEntry<K,V>[] newTable) {
725	<	threshold = (int)(newTable.length * loadFactor);
726	<	table = newTable;
724	>	@SuppressWarnings("unchecked") final TreeNode getTreeNode
725	>	(int h, Object k, TreeNode p) {
726	>	Class<?> c = k.getClass();
727	>	while (p != null) {
728	>	int dir, ph;  Object pk; Class<?> pc;
729	>	if ((ph = p.hash) == h) {
730	>	if ((pk = p.key) == k || k.equals(pk))
731	>	return p;
732	>	if (c != (pc = pk.getClass()) ||
733	>	!(k instanceof Comparable) ||
734	>	(dir = ((Comparable)k).compareTo((Comparable)pk)) == 0) {
735	>	dir = (c == pc) ? 0 : c.getName().compareTo(pc.getName());
736	>	TreeNode r = null, s = null, pl, pr;
737	>	if (dir >= 0) {
738	>	if ((pl = p.left) != null && h <= pl.hash)
739	>	s = pl;
740	>	}
741	>	else if ((pr = p.right) != null && h >= pr.hash)
742	>	s = pr;
743	>	if (s != null && (r = getTreeNode(h, k, s)) != null)
744	>	return r;
745	>	}
746	>	}
747	>	else
748	>	dir = (h < ph) ? -1 : 1;
749	>	p = (dir > 0) ? p.right : p.left;
750	>	}
751	>	return null;
752		}
753
754		/**
755	<	* Returns properly casted first entry of bin for given hash.
755	>	* Wrapper for getTreeNode used by CHM.get. Tries to obtain
756	>	* read-lock to call getTreeNode, but during failure to get
757	>	* lock, searches along next links.
758		*/
759	<	HashEntry<K,V> getFirst(int hash) {
760	<	HashEntry<K,V>[] tab = table;
761	<	return tab[hash & (tab.length - 1)];
759	>	final Object getValue(int h, Object k) {
760	>	Node r = null;
761	>	int c = getState(); // Must read lock state first
762	>	for (Node e = first; e != null; e = e.next) {
763	>	if (c <= 0 && compareAndSetState(c, c - 1)) {
764	>	try {
765	>	r = getTreeNode(h, k, root);
766	>	} finally {
767	>	releaseShared(0);
768	>	}
769	>	break;
770	>	}
771	>	else if ((e.hash & HASH_BITS) == h && k.equals(e.key)) {
772	>	r = e;
773	>	break;
774	>	}
775	>	else
776	>	c = getState();
777	>	}
778	>	return r == null ? null : r.val;
779		}
780
781		/**
782	<	* Reads value field of an entry under lock. Called if value
783	<	* field ever appears to be null. This is possible only if a
315	<	* compiler happens to reorder a HashEntry initialization with
316	<	* its table assignment, which is legal under memory model
317	<	* but is not known to ever occur.
782	>	* Finds or adds a node.
783	>	* @return null if added
784		*/
785	<	V readValueUnderLock(HashEntry<K,V> e) {
786	<	lock();
787	<	try {
788	<	return e.value;
789	<	} finally {
790	<	unlock();
785	>	@SuppressWarnings("unchecked") final TreeNode putTreeNode
786	>	(int h, Object k, Object v) {
787	>	Class<?> c = k.getClass();
788	>	TreeNode pp = root, p = null;
789	>	int dir = 0;
790	>	while (pp != null) { // find existing node or leaf to insert at
791	>	int ph;  Object pk; Class<?> pc;
792	>	p = pp;
793	>	if ((ph = p.hash) == h) {
794	>	if ((pk = p.key) == k || k.equals(pk))
795	>	return p;
796	>	if (c != (pc = pk.getClass()) ||
797	>	!(k instanceof Comparable) ||
798	>	(dir = ((Comparable)k).compareTo((Comparable)pk)) == 0) {
799	>	dir = (c == pc) ? 0 : c.getName().compareTo(pc.getName());
800	>	TreeNode r = null, s = null, pl, pr;
801	>	if (dir >= 0) {
802	>	if ((pl = p.left) != null && h <= pl.hash)
803	>	s = pl;
804	>	}
805	>	else if ((pr = p.right) != null && h >= pr.hash)
806	>	s = pr;
807	>	if (s != null && (r = getTreeNode(h, k, s)) != null)
808	>	return r;
809	>	}
810	>	}
811	>	else
812	>	dir = (h < ph) ? -1 : 1;
813	>	pp = (dir > 0) ? p.right : p.left;
814		}
326	–	}
327	–
328	–	/* Specialized implementations of map methods */
815
816	<	V get(Object key, int hash) {
817	<	if (count != 0) { // read-volatile
818	<	HashEntry<K,V> e = getFirst(hash);
819	<	while (e != null) {
820	<	if (e.hash == hash && key.equals(e.key)) {
821	<	V v = e.value;
822	<	if (v != null)
823	<	return v;
824	<	return readValueUnderLock(e); // recheck
816	>	TreeNode f = first;
817	>	TreeNode x = first = new TreeNode(h, k, v, f, p);
818	>	if (p == null)
819	>	root = x;
820	>	else { // attach and rebalance; adapted from CLR
821	>	TreeNode xp, xpp;
822	>	if (f != null)
823	>	f.prev = x;
824	>	if (dir <= 0)
825	>	p.left = x;
826	>	else
827	>	p.right = x;
828	>	x.red = true;
829	>	while (x != null && (xp = x.parent) != null && xp.red &&
830	>	(xpp = xp.parent) != null) {
831	>	TreeNode xppl = xpp.left;
832	>	if (xp == xppl) {
833	>	TreeNode y = xpp.right;
834	>	if (y != null && y.red) {
835	>	y.red = false;
836	>	xp.red = false;
837	>	xpp.red = true;
838	>	x = xpp;
839	>	}
840	>	else {
841	>	if (x == xp.right) {
842	>	rotateLeft(x = xp);
843	>	xpp = (xp = x.parent) == null ? null : xp.parent;
844	>	}
845	>	if (xp != null) {
846	>	xp.red = false;
847	>	if (xpp != null) {
848	>	xpp.red = true;
849	>	rotateRight(xpp);
850	>	}
851	>	}
852	>	}
853	>	}
854	>	else {
855	>	TreeNode y = xppl;
856	>	if (y != null && y.red) {
857	>	y.red = false;
858	>	xp.red = false;
859	>	xpp.red = true;
860	>	x = xpp;
861	>	}
862	>	else {
863	>	if (x == xp.left) {
864	>	rotateRight(x = xp);
865	>	xpp = (xp = x.parent) == null ? null : xp.parent;
866	>	}
867	>	if (xp != null) {
868	>	xp.red = false;
869	>	if (xpp != null) {
870	>	xpp.red = true;
871	>	rotateLeft(xpp);
872	>	}
873	>	}
874	>	}
875		}
340	–	e = e.next;
876		}
877	+	TreeNode r = root;
878	+	if (r != null && r.red)
879	+	r.red = false;
880		}
881		return null;
882		}
883
884	<	boolean containsKey(Object key, int hash) {
885	<	if (count != 0) { // read-volatile
886	<	HashEntry<K,V> e = getFirst(hash);
887	<	while (e != null) {
888	<	if (e.hash == hash && key.equals(e.key))
889	<	return true;
890	<	e = e.next;
884	>	/**
885	>	* Removes the given node, that must be present before this
886	>	* call.  This is messier than typical red-black deletion code
887	>	* because we cannot swap the contents of an interior node
888	>	* with a leaf successor that is pinned by "next" pointers
889	>	* that are accessible independently of lock. So instead we
890	>	* swap the tree linkages.
891	>	*/
892	>	final void deleteTreeNode(TreeNode p) {
893	>	TreeNode next = (TreeNode)p.next; // unlink traversal pointers
894	>	TreeNode pred = p.prev;
895	>	if (pred == null)
896	>	first = next;
897	>	else
898	>	pred.next = next;
899	>	if (next != null)
900	>	next.prev = pred;
901	>	TreeNode replacement;
902	>	TreeNode pl = p.left;
903	>	TreeNode pr = p.right;
904	>	if (pl != null && pr != null) {
905	>	TreeNode s = pr, sl;
906	>	while ((sl = s.left) != null) // find successor
907	>	s = sl;
908	>	boolean c = s.red; s.red = p.red; p.red = c; // swap colors
909	>	TreeNode sr = s.right;
910	>	TreeNode pp = p.parent;
911	>	if (s == pr) { // p was s's direct parent
912	>	p.parent = s;
913	>	s.right = p;
914		}
915	+	else {
916	+	TreeNode sp = s.parent;
917	+	if ((p.parent = sp) != null) {
918	+	if (s == sp.left)
919	+	sp.left = p;
920	+	else
921	+	sp.right = p;
922	+	}
923	+	if ((s.right = pr) != null)
924	+	pr.parent = s;
925	+	}
926	+	p.left = null;
927	+	if ((p.right = sr) != null)
928	+	sr.parent = p;
929	+	if ((s.left = pl) != null)
930	+	pl.parent = s;
931	+	if ((s.parent = pp) == null)
932	+	root = s;
933	+	else if (p == pp.left)
934	+	pp.left = s;
935	+	else
936	+	pp.right = s;
937	+	replacement = sr;
938		}
939	<	return false;
939	>	else
940	>	replacement = (pl != null) ? pl : pr;
941	>	TreeNode pp = p.parent;
942	>	if (replacement == null) {
943	>	if (pp == null) {
944	>	root = null;
945	>	return;
946	>	}
947	>	replacement = p;
948	>	}
949	>	else {
950	>	replacement.parent = pp;
951	>	if (pp == null)
952	>	root = replacement;
953	>	else if (p == pp.left)
954	>	pp.left = replacement;
955	>	else
956	>	pp.right = replacement;
957	>	p.left = p.right = p.parent = null;
958	>	}
959	>	if (!p.red) { // rebalance, from CLR
960	>	TreeNode x = replacement;
961	>	while (x != null) {
962	>	TreeNode xp, xpl;
963	>	if (x.red || (xp = x.parent) == null) {
964	>	x.red = false;
965	>	break;
966	>	}
967	>	if (x == (xpl = xp.left)) {
968	>	TreeNode sib = xp.right;
969	>	if (sib != null && sib.red) {
970	>	sib.red = false;
971	>	xp.red = true;
972	>	rotateLeft(xp);
973	>	sib = (xp = x.parent) == null ? null : xp.right;
974	>	}
975	>	if (sib == null)
976	>	x = xp;
977	>	else {
978	>	TreeNode sl = sib.left, sr = sib.right;
979	>	if ((sr == null || !sr.red) &&
980	>	(sl == null || !sl.red)) {
981	>	sib.red = true;
982	>	x = xp;
983	>	}
984	>	else {
985	>	if (sr == null || !sr.red) {
986	>	if (sl != null)
987	>	sl.red = false;
988	>	sib.red = true;
989	>	rotateRight(sib);
990	>	sib = (xp = x.parent) == null ? null : xp.right;
991	>	}
992	>	if (sib != null) {
993	>	sib.red = (xp == null) ? false : xp.red;
994	>	if ((sr = sib.right) != null)
995	>	sr.red = false;
996	>	}
997	>	if (xp != null) {
998	>	xp.red = false;
999	>	rotateLeft(xp);
1000	>	}
1001	>	x = root;
1002	>	}
1003	>	}
1004	>	}
1005	>	else { // symmetric
1006	>	TreeNode sib = xpl;
1007	>	if (sib != null && sib.red) {
1008	>	sib.red = false;
1009	>	xp.red = true;
1010	>	rotateRight(xp);
1011	>	sib = (xp = x.parent) == null ? null : xp.left;
1012	>	}
1013	>	if (sib == null)
1014	>	x = xp;
1015	>	else {
1016	>	TreeNode sl = sib.left, sr = sib.right;
1017	>	if ((sl == null || !sl.red) &&
1018	>	(sr == null || !sr.red)) {
1019	>	sib.red = true;
1020	>	x = xp;
1021	>	}
1022	>	else {
1023	>	if (sl == null || !sl.red) {
1024	>	if (sr != null)
1025	>	sr.red = false;
1026	>	sib.red = true;
1027	>	rotateLeft(sib);
1028	>	sib = (xp = x.parent) == null ? null : xp.left;
1029	>	}
1030	>	if (sib != null) {
1031	>	sib.red = (xp == null) ? false : xp.red;
1032	>	if ((sl = sib.left) != null)
1033	>	sl.red = false;
1034	>	}
1035	>	if (xp != null) {
1036	>	xp.red = false;
1037	>	rotateRight(xp);
1038	>	}
1039	>	x = root;
1040	>	}
1041	>	}
1042	>	}
1043	>	}
1044	>	}
1045	>	if (p == replacement && (pp = p.parent) != null) {
1046	>	if (p == pp.left) // detach pointers
1047	>	pp.left = null;
1048	>	else if (p == pp.right)
1049	>	pp.right = null;
1050	>	p.parent = null;
1051	>	}
1052	>	}
1053	>	}
1054	>
1055	>	/* ---------------- Collision reduction methods -------------- */
1056	>
1057	>	/**
1058	>	* Spreads higher bits to lower, and also forces top 2 bits to 0.
1059	>	* Because the table uses power-of-two masking, sets of hashes
1060	>	* that vary only in bits above the current mask will always
1061	>	* collide. (Among known examples are sets of Float keys holding
1062	>	* consecutive whole numbers in small tables.)  To counter this,
1063	>	* we apply a transform that spreads the impact of higher bits
1064	>	* downward. There is a tradeoff between speed, utility, and
1065	>	* quality of bit-spreading. Because many common sets of hashes
1066	>	* are already reasonably distributed across bits (so don't benefit
1067	>	* from spreading), and because we use trees to handle large sets
1068	>	* of collisions in bins, we don't need excessively high quality.
1069	>	*/
1070	>	private static final int spread(int h) {
1071	>	h ^= (h >>> 18) ^ (h >>> 12);
1072	>	return (h ^ (h >>> 10)) & HASH_BITS;
1073	>	}
1074	>
1075	>	/**
1076	>	* Replaces a list bin with a tree bin. Call only when locked.
1077	>	* Fails to replace if the given key is non-comparable or table
1078	>	* is, or needs, resizing.
1079	>	*/
1080	>	private final void replaceWithTreeBin(Node[] tab, int index, Object key) {
1081	>	if ((key instanceof Comparable) &&
1082	>	(tab.length >= MAXIMUM_CAPACITY || counter.sum() < (long)sizeCtl)) {
1083	>	TreeBin t = new TreeBin();
1084	>	for (Node e = tabAt(tab, index); e != null; e = e.next)
1085	>	t.putTreeNode(e.hash & HASH_BITS, e.key, e.val);
1086	>	setTabAt(tab, index, new Node(MOVED, t, null, null));
1087		}
1088	+	}
1089	+
1090	+	/* ---------------- Internal access and update methods -------------- */
1091
1092	<	boolean containsValue(Object value) {
1093	<	if (count != 0) { // read-volatile
1094	<	HashEntry<K,V>[] tab = table;
1095	<	int len = tab.length;
1096	<	for (int i = 0 ; i < len; i++) {
1097	<	for (HashEntry<K,V> e = tab[i]; e != null; e = e.next) {
1098	<	V v = e.value;
1099	<	if (v == null) // recheck
1100	<	v = readValueUnderLock(e);
1101	<	if (value.equals(v))
1102	<	return true;
1092	>	/** Implementation for get and containsKey */
1093	>	private final Object internalGet(Object k) {
1094	>	int h = spread(k.hashCode());
1095	>	retry: for (Node[] tab = table; tab != null;) {
1096	>	Node e, p; Object ek, ev; int eh;      // locals to read fields once
1097	>	for (e = tabAt(tab, (tab.length - 1) & h); e != null; e = e.next) {
1098	>	if ((eh = e.hash) == MOVED) {
1099	>	if ((ek = e.key) instanceof TreeBin)  // search TreeBin
1100	>	return ((TreeBin)ek).getValue(h, k);
1101	>	else {                        // restart with new table
1102	>	tab = (Node[])ek;
1103	>	continue retry;
1104		}
1105		}
1106	+	else if ((eh & HASH_BITS) == h && (ev = e.val) != null &&
1107	+	((ek = e.key) == k || k.equals(ek)))
1108	+	return ev;
1109		}
1110	<	return false;
1110	>	break;
1111		}
1112	+	return null;
1113	+	}
1114
1115	<	boolean replace(K key, int hash, V oldValue, V newValue) {
1116	<	lock();
1117	<	try {
1118	<	HashEntry<K,V> e = getFirst(hash);
1119	<	while (e != null && (e.hash != hash || !key.equals(e.key)))
1120	<	e = e.next;
1121	<
1122	<	boolean replaced = false;
1123	<	if (e != null && oldValue.equals(e.value)) {
1124	<	replaced = true;
1125	<	e.value = newValue;
1115	>	/**
1116	>	* Implementation for the four public remove/replace methods:
1117	>	* Replaces node value with v, conditional upon match of cv if
1118	>	* non-null.  If resulting value is null, delete.
1119	>	*/
1120	>	private final Object internalReplace(Object k, Object v, Object cv) {
1121	>	int h = spread(k.hashCode());
1122	>	Object oldVal = null;
1123	>	for (Node[] tab = table;;) {
1124	>	Node f; int i, fh; Object fk;
1125	>	if (tab == null ||
1126	>	(f = tabAt(tab, i = (tab.length - 1) & h)) == null)
1127	>	break;
1128	>	else if ((fh = f.hash) == MOVED) {
1129	>	if ((fk = f.key) instanceof TreeBin) {
1130	>	TreeBin t = (TreeBin)fk;
1131	>	boolean validated = false;
1132	>	boolean deleted = false;
1133	>	t.acquire(0);
1134	>	try {
1135	>	if (tabAt(tab, i) == f) {
1136	>	validated = true;
1137	>	TreeNode p = t.getTreeNode(h, k, t.root);
1138	>	if (p != null) {
1139	>	Object pv = p.val;
1140	>	if (cv == null || cv == pv || cv.equals(pv)) {
1141	>	oldVal = pv;
1142	>	if ((p.val = v) == null) {
1143	>	deleted = true;
1144	>	t.deleteTreeNode(p);
1145	>	}
1146	>	}
1147	>	}
1148	>	}
1149	>	} finally {
1150	>	t.release(0);
1151	>	}
1152	>	if (validated) {
1153	>	if (deleted)
1154	>	counter.add(-1L);
1155	>	break;
1156	>	}
1157	>	}
1158	>	else
1159	>	tab = (Node[])fk;
1160	>	}
1161	>	else if ((fh & HASH_BITS) != h && f.next == null) // precheck
1162	>	break;                          // rules out possible existence
1163	>	else if ((fh & LOCKED) != 0) {
1164	>	checkForResize();               // try resizing if can't get lock
1165	>	f.tryAwaitLock(tab, i);
1166	>	}
1167	>	else if (f.casHash(fh, fh | LOCKED)) {
1168	>	boolean validated = false;
1169	>	boolean deleted = false;
1170	>	try {
1171	>	if (tabAt(tab, i) == f) {
1172	>	validated = true;
1173	>	for (Node e = f, pred = null;;) {
1174	>	Object ek, ev;
1175	>	if ((e.hash & HASH_BITS) == h &&
1176	>	((ev = e.val) != null) &&
1177	>	((ek = e.key) == k || k.equals(ek))) {
1178	>	if (cv == null || cv == ev || cv.equals(ev)) {
1179	>	oldVal = ev;
1180	>	if ((e.val = v) == null) {
1181	>	deleted = true;
1182	>	Node en = e.next;
1183	>	if (pred != null)
1184	>	pred.next = en;
1185	>	else
1186	>	setTabAt(tab, i, en);
1187	>	}
1188	>	}
1189	>	break;
1190	>	}
1191	>	pred = e;
1192	>	if ((e = e.next) == null)
1193	>	break;
1194	>	}
1195	>	}
1196	>	} finally {
1197	>	if (!f.casHash(fh | LOCKED, fh)) {
1198	>	f.hash = fh;
1199	>	synchronized (f) { f.notifyAll(); };
1200	>	}
1201	>	}
1202	>	if (validated) {
1203	>	if (deleted)
1204	>	counter.add(-1L);
1205	>	break;
1206		}
387	–	return replaced;
388	–	} finally {
389	–	unlock();
1207		}
1208		}
1209	+	return oldVal;
1210	+	}
1211
1212	<	V replace(K key, int hash, V newValue) {
1213	<	lock();
1214	<	try {
1215	<	HashEntry<K,V> e = getFirst(hash);
1216	<	while (e != null && (e.hash != hash || !key.equals(e.key)))
1217	<	e = e.next;
1212	>	/*
1213	>	* Internal versions of the six insertion methods, each a
1214	>	* little more complicated than the last. All have
1215	>	* the same basic structure as the first (internalPut):
1216	>	*  1. If table uninitialized, create
1217	>	*  2. If bin empty, try to CAS new node
1218	>	*  3. If bin stale, use new table
1219	>	*  4. if bin converted to TreeBin, validate and relay to TreeBin methods
1220	>	*  5. Lock and validate; if valid, scan and add or update
1221	>	*
1222	>	* The others interweave other checks and/or alternative actions:
1223	>	*  * Plain put checks for and performs resize after insertion.
1224	>	*  * putIfAbsent prescans for mapping without lock (and fails to add
1225	>	*    if present), which also makes pre-emptive resize checks worthwhile.
1226	>	*  * computeIfAbsent extends form used in putIfAbsent with additional
1227	>	*    mechanics to deal with, calls, potential exceptions and null
1228	>	*    returns from function call.
1229	>	*  * compute uses the same function-call mechanics, but without
1230	>	*    the prescans
1231	>	*  * merge acts as putIfAbsent in the absent case, but invokes the
1232	>	*    update function if present
1233	>	*  * putAll attempts to pre-allocate enough table space
1234	>	*    and more lazily performs count updates and checks.
1235	>	*
1236	>	* Someday when details settle down a bit more, it might be worth
1237	>	* some factoring to reduce sprawl.
1238	>	*/
1239
1240	<	V oldValue = null;
1241	<	if (e != null) {
1242	<	oldValue = e.value;
1243	<	e.value = newValue;
1240	>	/** Implementation for put */
1241	>	private final Object internalPut(Object k, Object v) {
1242	>	int h = spread(k.hashCode());
1243	>	int count = 0;
1244	>	for (Node[] tab = table;;) {
1245	>	int i; Node f; int fh; Object fk;
1246	>	if (tab == null)
1247	>	tab = initTable();
1248	>	else if ((f = tabAt(tab, i = (tab.length - 1) & h)) == null) {
1249	>	if (casTabAt(tab, i, null, new Node(h, k, v, null)))
1250	>	break;                   // no lock when adding to empty bin
1251	>	}
1252	>	else if ((fh = f.hash) == MOVED) {
1253	>	if ((fk = f.key) instanceof TreeBin) {
1254	>	TreeBin t = (TreeBin)fk;
1255	>	Object oldVal = null;
1256	>	t.acquire(0);
1257	>	try {
1258	>	if (tabAt(tab, i) == f) {
1259	>	count = 2;
1260	>	TreeNode p = t.putTreeNode(h, k, v);
1261	>	if (p != null) {
1262	>	oldVal = p.val;
1263	>	p.val = v;
1264	>	}
1265	>	}
1266	>	} finally {
1267	>	t.release(0);
1268	>	}
1269	>	if (count != 0) {
1270	>	if (oldVal != null)
1271	>	return oldVal;
1272	>	break;
1273	>	}
1274	>	}
1275	>	else
1276	>	tab = (Node[])fk;
1277	>	}
1278	>	else if ((fh & LOCKED) != 0) {
1279	>	checkForResize();
1280	>	f.tryAwaitLock(tab, i);
1281	>	}
1282	>	else if (f.casHash(fh, fh | LOCKED)) {
1283	>	Object oldVal = null;
1284	>	try {                        // needed in case equals() throws
1285	>	if (tabAt(tab, i) == f) {
1286	>	count = 1;
1287	>	for (Node e = f;; ++count) {
1288	>	Object ek, ev;
1289	>	if ((e.hash & HASH_BITS) == h &&
1290	>	(ev = e.val) != null &&
1291	>	((ek = e.key) == k || k.equals(ek))) {
1292	>	oldVal = ev;
1293	>	e.val = v;
1294	>	break;
1295	>	}
1296	>	Node last = e;
1297	>	if ((e = e.next) == null) {
1298	>	last.next = new Node(h, k, v, null);
1299	>	if (count >= TREE_THRESHOLD)
1300	>	replaceWithTreeBin(tab, i, k);
1301	>	break;
1302	>	}
1303	>	}
1304	>	}
1305	>	} finally {                  // unlock and signal if needed
1306	>	if (!f.casHash(fh | LOCKED, fh)) {
1307	>	f.hash = fh;
1308	>	synchronized (f) { f.notifyAll(); };
1309	>	}
1310	>	}
1311	>	if (count != 0) {
1312	>	if (oldVal != null)
1313	>	return oldVal;
1314	>	if (tab.length <= 64)
1315	>	count = 2;
1316	>	break;
1317		}
405	–	return oldValue;
406	–	} finally {
407	–	unlock();
1318		}
1319		}
1320	+	counter.add(1L);
1321	+	if (count > 1)
1322	+	checkForResize();
1323	+	return null;
1324	+	}
1325
1326	+	/** Implementation for putIfAbsent */
1327	+	private final Object internalPutIfAbsent(Object k, Object v) {
1328	+	int h = spread(k.hashCode());
1329	+	int count = 0;
1330	+	for (Node[] tab = table;;) {
1331	+	int i; Node f; int fh; Object fk, fv;
1332	+	if (tab == null)
1333	+	tab = initTable();
1334	+	else if ((f = tabAt(tab, i = (tab.length - 1) & h)) == null) {
1335	+	if (casTabAt(tab, i, null, new Node(h, k, v, null)))
1336	+	break;
1337	+	}
1338	+	else if ((fh = f.hash) == MOVED) {
1339	+	if ((fk = f.key) instanceof TreeBin) {
1340	+	TreeBin t = (TreeBin)fk;
1341	+	Object oldVal = null;
1342	+	t.acquire(0);
1343	+	try {
1344	+	if (tabAt(tab, i) == f) {
1345	+	count = 2;
1346	+	TreeNode p = t.putTreeNode(h, k, v);
1347	+	if (p != null)
1348	+	oldVal = p.val;
1349	+	}
1350	+	} finally {
1351	+	t.release(0);
1352	+	}
1353	+	if (count != 0) {
1354	+	if (oldVal != null)
1355	+	return oldVal;
1356	+	break;
1357	+	}
1358	+	}
1359	+	else
1360	+	tab = (Node[])fk;
1361	+	}
1362	+	else if ((fh & HASH_BITS) == h && (fv = f.val) != null &&
1363	+	((fk = f.key) == k || k.equals(fk)))
1364	+	return fv;
1365	+	else {
1366	+	Node g = f.next;
1367	+	if (g != null) { // at least 2 nodes -- search and maybe resize
1368	+	for (Node e = g;;) {
1369	+	Object ek, ev;
1370	+	if ((e.hash & HASH_BITS) == h && (ev = e.val) != null &&
1371	+	((ek = e.key) == k || k.equals(ek)))
1372	+	return ev;
1373	+	if ((e = e.next) == null) {
1374	+	checkForResize();
1375	+	break;
1376	+	}
1377	+	}
1378	+	}
1379	+	if (((fh = f.hash) & LOCKED) != 0) {
1380	+	checkForResize();
1381	+	f.tryAwaitLock(tab, i);
1382	+	}
1383	+	else if (tabAt(tab, i) == f && f.casHash(fh, fh | LOCKED)) {
1384	+	Object oldVal = null;
1385	+	try {
1386	+	if (tabAt(tab, i) == f) {
1387	+	count = 1;
1388	+	for (Node e = f;; ++count) {
1389	+	Object ek, ev;
1390	+	if ((e.hash & HASH_BITS) == h &&
1391	+	(ev = e.val) != null &&
1392	+	((ek = e.key) == k || k.equals(ek))) {
1393	+	oldVal = ev;
1394	+	break;
1395	+	}
1396	+	Node last = e;
1397	+	if ((e = e.next) == null) {
1398	+	last.next = new Node(h, k, v, null);
1399	+	if (count >= TREE_THRESHOLD)
1400	+	replaceWithTreeBin(tab, i, k);
1401	+	break;
1402	+	}
1403	+	}
1404	+	}
1405	+	} finally {
1406	+	if (!f.casHash(fh | LOCKED, fh)) {
1407	+	f.hash = fh;
1408	+	synchronized (f) { f.notifyAll(); };
1409	+	}
1410	+	}
1411	+	if (count != 0) {
1412	+	if (oldVal != null)
1413	+	return oldVal;
1414	+	if (tab.length <= 64)
1415	+	count = 2;
1416	+	break;
1417	+	}
1418	+	}
1419	+	}
1420	+	}
1421	+	counter.add(1L);
1422	+	if (count > 1)
1423	+	checkForResize();
1424	+	return null;
1425	+	}
1426
1427	<	V put(K key, int hash, V value, boolean onlyIfAbsent) {
1428	<	lock();
1429	<	try {
1430	<	int c = count;
1431	<	if (c++ > threshold) // ensure capacity
1432	<	rehash();
1433	<	HashEntry<K,V>[] tab = table;
1434	<	int index = hash & (tab.length - 1);
1435	<	HashEntry<K,V> first = tab[index];
1436	<	HashEntry<K,V> e = first;
1437	<	while (e != null && (e.hash != hash || !key.equals(e.key)))
1438	<	e = e.next;
1439	<
1440	<	V oldValue;
1441	<	if (e != null) {
1442	<	oldValue = e.value;
1443	<	if (!onlyIfAbsent)
1444	<	e.value = value;
1427	>	/** Implementation for computeIfAbsent */
1428	>	private final Object internalComputeIfAbsent(K k,
1429	>	Fun<? super K, ?> mf) {
1430	>	int h = spread(k.hashCode());
1431	>	Object val = null;
1432	>	int count = 0;
1433	>	for (Node[] tab = table;;) {
1434	>	Node f; int i, fh; Object fk, fv;
1435	>	if (tab == null)
1436	>	tab = initTable();
1437	>	else if ((f = tabAt(tab, i = (tab.length - 1) & h)) == null) {
1438	>	Node node = new Node(fh = h | LOCKED, k, null, null);
1439	>	if (casTabAt(tab, i, null, node)) {
1440	>	count = 1;
1441	>	try {
1442	>	if ((val = mf.apply(k)) != null)
1443	>	node.val = val;
1444	>	} finally {
1445	>	if (val == null)
1446	>	setTabAt(tab, i, null);
1447	>	if (!node.casHash(fh, h)) {
1448	>	node.hash = h;
1449	>	synchronized (node) { node.notifyAll(); };
1450	>	}
1451	>	}
1452		}
1453	<	else {
1454	<	oldValue = null;
1455	<	++modCount;
1456	<	tab[index] = new HashEntry<K,V>(key, hash, first, value);
1457	<	count = c; // write-volatile
1453	>	if (count != 0)
1454	>	break;
1455	>	}
1456	>	else if ((fh = f.hash) == MOVED) {
1457	>	if ((fk = f.key) instanceof TreeBin) {
1458	>	TreeBin t = (TreeBin)fk;
1459	>	boolean added = false;
1460	>	t.acquire(0);
1461	>	try {
1462	>	if (tabAt(tab, i) == f) {
1463	>	count = 1;
1464	>	TreeNode p = t.getTreeNode(h, k, t.root);
1465	>	if (p != null)
1466	>	val = p.val;
1467	>	else if ((val = mf.apply(k)) != null) {
1468	>	added = true;
1469	>	count = 2;
1470	>	t.putTreeNode(h, k, val);
1471	>	}
1472	>	}
1473	>	} finally {
1474	>	t.release(0);
1475	>	}
1476	>	if (count != 0) {
1477	>	if (!added)
1478	>	return val;
1479	>	break;
1480	>	}
1481	>	}
1482	>	else
1483	>	tab = (Node[])fk;
1484	>	}
1485	>	else if ((fh & HASH_BITS) == h && (fv = f.val) != null &&
1486	>	((fk = f.key) == k || k.equals(fk)))
1487	>	return fv;
1488	>	else {
1489	>	Node g = f.next;
1490	>	if (g != null) {
1491	>	for (Node e = g;;) {
1492	>	Object ek, ev;
1493	>	if ((e.hash & HASH_BITS) == h && (ev = e.val) != null &&
1494	>	((ek = e.key) == k || k.equals(ek)))
1495	>	return ev;
1496	>	if ((e = e.next) == null) {
1497	>	checkForResize();
1498	>	break;
1499	>	}
1500	>	}
1501	>	}
1502	>	if (((fh = f.hash) & LOCKED) != 0) {
1503	>	checkForResize();
1504	>	f.tryAwaitLock(tab, i);
1505	>	}
1506	>	else if (tabAt(tab, i) == f && f.casHash(fh, fh | LOCKED)) {
1507	>	boolean added = false;
1508	>	try {
1509	>	if (tabAt(tab, i) == f) {
1510	>	count = 1;
1511	>	for (Node e = f;; ++count) {
1512	>	Object ek, ev;
1513	>	if ((e.hash & HASH_BITS) == h &&
1514	>	(ev = e.val) != null &&
1515	>	((ek = e.key) == k || k.equals(ek))) {
1516	>	val = ev;
1517	>	break;
1518	>	}
1519	>	Node last = e;
1520	>	if ((e = e.next) == null) {
1521	>	if ((val = mf.apply(k)) != null) {
1522	>	added = true;
1523	>	last.next = new Node(h, k, val, null);
1524	>	if (count >= TREE_THRESHOLD)
1525	>	replaceWithTreeBin(tab, i, k);
1526	>	}
1527	>	break;
1528	>	}
1529	>	}
1530	>	}
1531	>	} finally {
1532	>	if (!f.casHash(fh | LOCKED, fh)) {
1533	>	f.hash = fh;
1534	>	synchronized (f) { f.notifyAll(); };
1535	>	}
1536	>	}
1537	>	if (count != 0) {
1538	>	if (!added)
1539	>	return val;
1540	>	if (tab.length <= 64)
1541	>	count = 2;
1542	>	break;
1543	>	}
1544		}
437	–	return oldValue;
438	–	} finally {
439	–	unlock();
1545		}
1546		}
1547	+	if (val != null) {
1548	+	counter.add(1L);
1549	+	if (count > 1)
1550	+	checkForResize();
1551	+	}
1552	+	return val;
1553	+	}
1554
1555	<	void rehash() {
1556	<	HashEntry<K,V>[] oldTable = table;
1557	<	int oldCapacity = oldTable.length;
1558	<	if (oldCapacity >= MAXIMUM_CAPACITY)
1559	<	return;
1560	<
1561	<	/*
1562	<	* Reclassify nodes in each list to new Map.  Because we are
1563	<	* using power-of-two expansion, the elements from each bin
1564	<	* must either stay at same index, or move with a power of two
1565	<	* offset. We eliminate unnecessary node creation by catching
1566	<	* cases where old nodes can be reused because their next
1567	<	* fields won't change. Statistically, at the default
1568	<	* threshold, only about one-sixth of them need cloning when
1569	<	* a table doubles. The nodes they replace will be garbage
1570	<	* collectable as soon as they are no longer referenced by any
1571	<	* reader thread that may be in the midst of traversing table
1572	<	* right now.
1573	<	*/
1574	<
1575	<	HashEntry<K,V>[] newTable = HashEntry.newArray(oldCapacity<<1);
1576	<	threshold = (int)(newTable.length * loadFactor);
1577	<	int sizeMask = newTable.length - 1;
1578	<	for (int i = 0; i < oldCapacity ; i++) {
1579	<	// We need to guarantee that any existing reads of old Map can
1580	<	//  proceed. So we cannot yet null out each bin.
1581	<	HashEntry<K,V> e = oldTable[i];
1582	<
1583	<	if (e != null) {
1584	<	HashEntry<K,V> next = e.next;
1585	<	int idx = e.hash & sizeMask;
1586	<
1587	<	//  Single node on list
1588	<	if (next == null)
1589	<	newTable[idx] = e;
1555	>	/** Implementation for compute */
1556	>	@SuppressWarnings("unchecked") private final Object internalCompute
1557	>	(K k, boolean onlyIfPresent, BiFun<? super K, ? super V, ? extends V> mf) {
1558	>	int h = spread(k.hashCode());
1559	>	Object val = null;
1560	>	int delta = 0;
1561	>	int count = 0;
1562	>	for (Node[] tab = table;;) {
1563	>	Node f; int i, fh; Object fk;
1564	>	if (tab == null)
1565	>	tab = initTable();
1566	>	else if ((f = tabAt(tab, i = (tab.length - 1) & h)) == null) {
1567	>	if (onlyIfPresent)
1568	>	break;
1569	>	Node node = new Node(fh = h | LOCKED, k, null, null);
1570	>	if (casTabAt(tab, i, null, node)) {
1571	>	try {
1572	>	count = 1;
1573	>	if ((val = mf.apply(k, null)) != null) {
1574	>	node.val = val;
1575	>	delta = 1;
1576	>	}
1577	>	} finally {
1578	>	if (delta == 0)
1579	>	setTabAt(tab, i, null);
1580	>	if (!node.casHash(fh, h)) {
1581	>	node.hash = h;
1582	>	synchronized (node) { node.notifyAll(); };
1583	>	}
1584	>	}
1585	>	}
1586	>	if (count != 0)
1587	>	break;
1588	>	}
1589	>	else if ((fh = f.hash) == MOVED) {
1590	>	if ((fk = f.key) instanceof TreeBin) {
1591	>	TreeBin t = (TreeBin)fk;
1592	>	t.acquire(0);
1593	>	try {
1594	>	if (tabAt(tab, i) == f) {
1595	>	count = 1;
1596	>	TreeNode p = t.getTreeNode(h, k, t.root);
1597	>	Object pv = (p == null) ? null : p.val;
1598	>	if ((val = mf.apply(k, (V)pv)) != null) {
1599	>	if (p != null)
1600	>	p.val = val;
1601	>	else {
1602	>	count = 2;
1603	>	delta = 1;
1604	>	t.putTreeNode(h, k, val);
1605	>	}
1606	>	}
1607	>	else if (p != null) {
1608	>	delta = -1;
1609	>	t.deleteTreeNode(p);
1610	>	}
1611	>	}
1612	>	} finally {
1613	>	t.release(0);
1614	>	}
1615	>	if (count != 0)
1616	>	break;
1617	>	}
1618	>	else
1619	>	tab = (Node[])fk;
1620	>	}
1621	>	else if ((fh & LOCKED) != 0) {
1622	>	checkForResize();
1623	>	f.tryAwaitLock(tab, i);
1624	>	}
1625	>	else if (f.casHash(fh, fh | LOCKED)) {
1626	>	try {
1627	>	if (tabAt(tab, i) == f) {
1628	>	count = 1;
1629	>	for (Node e = f, pred = null;; ++count) {
1630	>	Object ek, ev;
1631	>	if ((e.hash & HASH_BITS) == h &&
1632	>	(ev = e.val) != null &&
1633	>	((ek = e.key) == k || k.equals(ek))) {
1634	>	val = mf.apply(k, (V)ev);
1635	>	if (val != null)
1636	>	e.val = val;
1637	>	else {
1638	>	delta = -1;
1639	>	Node en = e.next;
1640	>	if (pred != null)
1641	>	pred.next = en;
1642	>	else
1643	>	setTabAt(tab, i, en);
1644	>	}
1645	>	break;
1646	>	}
1647	>	pred = e;
1648	>	if ((e = e.next) == null) {
1649	>	if (!onlyIfPresent && (val = mf.apply(k, null)) != null) {
1650	>	pred.next = new Node(h, k, val, null);
1651	>	delta = 1;
1652	>	if (count >= TREE_THRESHOLD)
1653	>	replaceWithTreeBin(tab, i, k);
1654	>	}
1655	>	break;
1656	>	}
1657	>	}
1658	>	}
1659	>	} finally {
1660	>	if (!f.casHash(fh | LOCKED, fh)) {
1661	>	f.hash = fh;
1662	>	synchronized (f) { f.notifyAll(); };
1663	>	}
1664	>	}
1665	>	if (count != 0) {
1666	>	if (tab.length <= 64)
1667	>	count = 2;
1668	>	break;
1669	>	}
1670	>	}
1671	>	}
1672	>	if (delta != 0) {
1673	>	counter.add((long)delta);
1674	>	if (count > 1)
1675	>	checkForResize();
1676	>	}
1677	>	return val;
1678	>	}
1679
1680	<	else {
1681	<	// Reuse trailing consecutive sequence at same slot
1682	<	HashEntry<K,V> lastRun = e;
1683	<	int lastIdx = idx;
1684	<	for (HashEntry<K,V> last = next;
1685	<	last != null;
1686	<	last = last.next) {
1687	<	int k = last.hash & sizeMask;
1688	<	if (k != lastIdx) {
1689	<	lastIdx = k;
1690	<	lastRun = last;
1680	>	/** Implementation for merge */
1681	>	@SuppressWarnings("unchecked") private final Object internalMerge
1682	>	(K k, V v, BiFun<? super V, ? super V, ? extends V> mf) {
1683	>	int h = spread(k.hashCode());
1684	>	Object val = null;
1685	>	int delta = 0;
1686	>	int count = 0;
1687	>	for (Node[] tab = table;;) {
1688	>	int i; Node f; int fh; Object fk, fv;
1689	>	if (tab == null)
1690	>	tab = initTable();
1691	>	else if ((f = tabAt(tab, i = (tab.length - 1) & h)) == null) {
1692	>	if (casTabAt(tab, i, null, new Node(h, k, v, null))) {
1693	>	delta = 1;
1694	>	val = v;
1695	>	break;
1696	>	}
1697	>	}
1698	>	else if ((fh = f.hash) == MOVED) {
1699	>	if ((fk = f.key) instanceof TreeBin) {
1700	>	TreeBin t = (TreeBin)fk;
1701	>	t.acquire(0);
1702	>	try {
1703	>	if (tabAt(tab, i) == f) {
1704	>	count = 1;
1705	>	TreeNode p = t.getTreeNode(h, k, t.root);
1706	>	val = (p == null) ? v : mf.apply((V)p.val, v);
1707	>	if (val != null) {
1708	>	if (p != null)
1709	>	p.val = val;
1710	>	else {
1711	>	count = 2;
1712	>	delta = 1;
1713	>	t.putTreeNode(h, k, val);
1714	>	}
1715	>	}
1716	>	else if (p != null) {
1717	>	delta = -1;
1718	>	t.deleteTreeNode(p);
1719	>	}
1720	>	}
1721	>	} finally {
1722	>	t.release(0);
1723	>	}
1724	>	if (count != 0)
1725	>	break;
1726	>	}
1727	>	else
1728	>	tab = (Node[])fk;
1729	>	}
1730	>	else if ((fh & LOCKED) != 0) {
1731	>	checkForResize();
1732	>	f.tryAwaitLock(tab, i);
1733	>	}
1734	>	else if (f.casHash(fh, fh | LOCKED)) {
1735	>	try {
1736	>	if (tabAt(tab, i) == f) {
1737	>	count = 1;
1738	>	for (Node e = f, pred = null;; ++count) {
1739	>	Object ek, ev;
1740	>	if ((e.hash & HASH_BITS) == h &&
1741	>	(ev = e.val) != null &&
1742	>	((ek = e.key) == k || k.equals(ek))) {
1743	>	val = mf.apply(v, (V)ev);
1744	>	if (val != null)
1745	>	e.val = val;
1746	>	else {
1747	>	delta = -1;
1748	>	Node en = e.next;
1749	>	if (pred != null)
1750	>	pred.next = en;
1751	>	else
1752	>	setTabAt(tab, i, en);
1753	>	}
1754	>	break;
1755	>	}
1756	>	pred = e;
1757	>	if ((e = e.next) == null) {
1758	>	val = v;
1759	>	pred.next = new Node(h, k, val, null);
1760	>	delta = 1;
1761	>	if (count >= TREE_THRESHOLD)
1762	>	replaceWithTreeBin(tab, i, k);
1763	>	break;
1764		}
1765		}
1766	<	newTable[lastIdx] = lastRun;
1766	>	}
1767	>	} finally {
1768	>	if (!f.casHash(fh | LOCKED, fh)) {
1769	>	f.hash = fh;
1770	>	synchronized (f) { f.notifyAll(); };
1771	>	}
1772	>	}
1773	>	if (count != 0) {
1774	>	if (tab.length <= 64)
1775	>	count = 2;
1776	>	break;
1777	>	}
1778	>	}
1779	>	}
1780	>	if (delta != 0) {
1781	>	counter.add((long)delta);
1782	>	if (count > 1)
1783	>	checkForResize();
1784	>	}
1785	>	return val;
1786	>	}
1787
1788	<	// Clone all remaining nodes
1789	<	for (HashEntry<K,V> p = e; p != lastRun; p = p.next) {
1790	<	int k = p.hash & sizeMask;
1791	<	HashEntry<K,V> n = newTable[k];
1792	<	newTable[k] = new HashEntry<K,V>(p.key, p.hash,
1793	<	n, p.value);
1788	>	/** Implementation for putAll */
1789	>	private final void internalPutAll(Map<?, ?> m) {
1790	>	tryPresize(m.size());
1791	>	long delta = 0L;     // number of uncommitted additions
1792	>	boolean npe = false; // to throw exception on exit for nulls
1793	>	try {                // to clean up counts on other exceptions
1794	>	for (Map.Entry<?, ?> entry : m.entrySet()) {
1795	>	Object k, v;
1796	>	if (entry == null || (k = entry.getKey()) == null ||
1797	>	(v = entry.getValue()) == null) {
1798	>	npe = true;
1799	>	break;
1800	>	}
1801	>	int h = spread(k.hashCode());
1802	>	for (Node[] tab = table;;) {
1803	>	int i; Node f; int fh; Object fk;
1804	>	if (tab == null)
1805	>	tab = initTable();
1806	>	else if ((f = tabAt(tab, i = (tab.length - 1) & h)) == null){
1807	>	if (casTabAt(tab, i, null, new Node(h, k, v, null))) {
1808	>	++delta;
1809	>	break;
1810	>	}
1811	>	}
1812	>	else if ((fh = f.hash) == MOVED) {
1813	>	if ((fk = f.key) instanceof TreeBin) {
1814	>	TreeBin t = (TreeBin)fk;
1815	>	boolean validated = false;
1816	>	t.acquire(0);
1817	>	try {
1818	>	if (tabAt(tab, i) == f) {
1819	>	validated = true;
1820	>	TreeNode p = t.getTreeNode(h, k, t.root);
1821	>	if (p != null)
1822	>	p.val = v;
1823	>	else {
1824	>	t.putTreeNode(h, k, v);
1825	>	++delta;
1826	>	}
1827	>	}
1828	>	} finally {
1829	>	t.release(0);
1830	>	}
1831	>	if (validated)
1832	>	break;
1833	>	}
1834	>	else
1835	>	tab = (Node[])fk;
1836	>	}
1837	>	else if ((fh & LOCKED) != 0) {
1838	>	counter.add(delta);
1839	>	delta = 0L;
1840	>	checkForResize();
1841	>	f.tryAwaitLock(tab, i);
1842	>	}
1843	>	else if (f.casHash(fh, fh | LOCKED)) {
1844	>	int count = 0;
1845	>	try {
1846	>	if (tabAt(tab, i) == f) {
1847	>	count = 1;
1848	>	for (Node e = f;; ++count) {
1849	>	Object ek, ev;
1850	>	if ((e.hash & HASH_BITS) == h &&
1851	>	(ev = e.val) != null &&
1852	>	((ek = e.key) == k || k.equals(ek))) {
1853	>	e.val = v;
1854	>	break;
1855	>	}
1856	>	Node last = e;
1857	>	if ((e = e.next) == null) {
1858	>	++delta;
1859	>	last.next = new Node(h, k, v, null);
1860	>	if (count >= TREE_THRESHOLD)
1861	>	replaceWithTreeBin(tab, i, k);
1862	>	break;
1863	>	}
1864	>	}
1865	>	}
1866	>	} finally {
1867	>	if (!f.casHash(fh | LOCKED, fh)) {
1868	>	f.hash = fh;
1869	>	synchronized (f) { f.notifyAll(); };
1870	>	}
1871	>	}
1872	>	if (count != 0) {
1873	>	if (count > 1) {
1874	>	counter.add(delta);
1875	>	delta = 0L;
1876	>	checkForResize();
1877	>	}
1878	>	break;
1879		}
1880		}
1881		}
1882		}
1883	<	table = newTable;
1883	>	} finally {
1884	>	if (delta != 0)
1885	>	counter.add(delta);
1886		}
1887	+	if (npe)
1888	+	throw new NullPointerException();
1889	+	}
1890
1891	<	/**
1892	<	* Remove; match on key only if value null, else match both.
1893	<	*/
1894	<	V remove(Object key, int hash, Object value) {
1895	<	lock();
1896	<	try {
1897	<	int c = count - 1;
1898	<	HashEntry<K,V>[] tab = table;
1899	<	int index = hash & (tab.length - 1);
1900	<	HashEntry<K,V> first = tab[index];
1901	<	HashEntry<K,V> e = first;
1902	<	while (e != null && (e.hash != hash || !key.equals(e.key)))
1903	<	e = e.next;
1891	>	/* ---------------- Table Initialization and Resizing -------------- */
1892	>
1893	>	/**
1894	>	* Returns a power of two table size for the given desired capacity.
1895	>	* See Hackers Delight, sec 3.2
1896	>	*/
1897	>	private static final int tableSizeFor(int c) {
1898	>	int n = c - 1;
1899	>	n |= n >>> 1;
1900	>	n |= n >>> 2;
1901	>	n |= n >>> 4;
1902	>	n |= n >>> 8;
1903	>	n |= n >>> 16;
1904	>	return (n < 0) ? 1 : (n >= MAXIMUM_CAPACITY) ? MAXIMUM_CAPACITY : n + 1;
1905	>	}
1906
1907	<	V oldValue = null;
1908	<	if (e != null) {
1909	<	V v = e.value;
1910	<	if (value == null || value.equals(v)) {
1911	<	oldValue = v;
1912	<	// All entries following removed node can stay
1913	<	// in list, but all preceding ones need to be
1914	<	// cloned.
1915	<	++modCount;
1916	<	HashEntry<K,V> newFirst = e.next;
1917	<	for (HashEntry<K,V> p = first; p != e; p = p.next)
1918	<	newFirst = new HashEntry<K,V>(p.key, p.hash,
1919	<	newFirst, p.value);
1920	<	tab[index] = newFirst;
535	<	count = c; // write-volatile
1907	>	/**
1908	>	* Initializes table, using the size recorded in sizeCtl.
1909	>	*/
1910	>	private final Node[] initTable() {
1911	>	Node[] tab; int sc;
1912	>	while ((tab = table) == null) {
1913	>	if ((sc = sizeCtl) < 0)
1914	>	Thread.yield(); // lost initialization race; just spin
1915	>	else if (UNSAFE.compareAndSwapInt(this, sizeCtlOffset, sc, -1)) {
1916	>	try {
1917	>	if ((tab = table) == null) {
1918	>	int n = (sc > 0) ? sc : DEFAULT_CAPACITY;
1919	>	tab = table = new Node[n];
1920	>	sc = n - (n >>> 2);
1921		}
1922	+	} finally {
1923	+	sizeCtl = sc;
1924	+	}
1925	+	break;
1926	+	}
1927	+	}
1928	+	return tab;
1929	+	}
1930	+
1931	+	/**
1932	+	* If table is too small and not already resizing, creates next
1933	+	* table and transfers bins.  Rechecks occupancy after a transfer
1934	+	* to see if another resize is already needed because resizings
1935	+	* are lagging additions.
1936	+	*/
1937	+	private final void checkForResize() {
1938	+	Node[] tab; int n, sc;
1939	+	while ((tab = table) != null &&
1940	+	(n = tab.length) < MAXIMUM_CAPACITY &&
1941	+	(sc = sizeCtl) >= 0 && counter.sum() >= (long)sc &&
1942	+	UNSAFE.compareAndSwapInt(this, sizeCtlOffset, sc, -1)) {
1943	+	try {
1944	+	if (tab == table) {
1945	+	table = rebuild(tab);
1946	+	sc = (n << 1) - (n >>> 1);
1947		}
538	–	return oldValue;
1948		} finally {
1949	<	unlock();
1949	>	sizeCtl = sc;
1950		}
1951		}
1952	+	}
1953
1954	<	void clear() {
1955	<	if (count != 0) {
1956	<	lock();
1954	>	/**
1955	>	* Tries to presize table to accommodate the given number of elements.
1956	>	*
1957	>	* @param size number of elements (doesn't need to be perfectly accurate)
1958	>	*/
1959	>	private final void tryPresize(int size) {
1960	>	int c = (size >= (MAXIMUM_CAPACITY >>> 1)) ? MAXIMUM_CAPACITY :
1961	>	tableSizeFor(size + (size >>> 1) + 1);
1962	>	int sc;
1963	>	while ((sc = sizeCtl) >= 0) {
1964	>	Node[] tab = table; int n;
1965	>	if (tab == null || (n = tab.length) == 0) {
1966	>	n = (sc > c) ? sc : c;
1967	>	if (UNSAFE.compareAndSwapInt(this, sizeCtlOffset, sc, -1)) {
1968	>	try {
1969	>	if (table == tab) {
1970	>	table = new Node[n];
1971	>	sc = n - (n >>> 2);
1972	>	}
1973	>	} finally {
1974	>	sizeCtl = sc;
1975	>	}
1976	>	}
1977	>	}
1978	>	else if (c <= sc || n >= MAXIMUM_CAPACITY)
1979	>	break;
1980	>	else if (UNSAFE.compareAndSwapInt(this, sizeCtlOffset, sc, -1)) {
1981		try {
1982	<	HashEntry<K,V>[] tab = table;
1983	<	for (int i = 0; i < tab.length ; i++)
1984	<	tab[i] = null;
1985	<	++modCount;
552	<	count = 0; // write-volatile
1982	>	if (table == tab) {
1983	>	table = rebuild(tab);
1984	>	sc = (n << 1) - (n >>> 1);
1985	>	}
1986		} finally {
1987	<	unlock();
1987	>	sizeCtl = sc;
1988		}
1989		}
1990		}
1991		}
1992
1993	+	/*
1994	+	* Moves and/or copies the nodes in each bin to new table. See
1995	+	* above for explanation.
1996	+	*
1997	+	* @return the new table
1998	+	*/
1999	+	private static final Node[] rebuild(Node[] tab) {
2000	+	int n = tab.length;
2001	+	Node[] nextTab = new Node[n << 1];
2002	+	Node fwd = new Node(MOVED, nextTab, null, null);
2003	+	int[] buffer = null;       // holds bins to revisit; null until needed
2004	+	Node rev = null;           // reverse forwarder; null until needed
2005	+	int nbuffered = 0;         // the number of bins in buffer list
2006	+	int bufferIndex = 0;       // buffer index of current buffered bin
2007	+	int bin = n - 1;           // current non-buffered bin or -1 if none
2008	+
2009	+	for (int i = bin;;) {      // start upwards sweep
2010	+	int fh; Node f;
2011	+	if ((f = tabAt(tab, i)) == null) {
2012	+	if (bin >= 0) {    // Unbuffered; no lock needed (or available)
2013	+	if (!casTabAt(tab, i, f, fwd))
2014	+	continue;
2015	+	}
2016	+	else {             // transiently use a locked forwarding node
2017	+	Node g = new Node(MOVED|LOCKED, nextTab, null, null);
2018	+	if (!casTabAt(tab, i, f, g))
2019	+	continue;
2020	+	setTabAt(nextTab, i, null);
2021	+	setTabAt(nextTab, i + n, null);
2022	+	setTabAt(tab, i, fwd);
2023	+	if (!g.casHash(MOVED|LOCKED, MOVED)) {
2024	+	g.hash = MOVED;
2025	+	synchronized (g) { g.notifyAll(); }
2026	+	}
2027	+	}
2028	+	}
2029	+	else if ((fh = f.hash) == MOVED) {
2030	+	Object fk = f.key;
2031	+	if (fk instanceof TreeBin) {
2032	+	TreeBin t = (TreeBin)fk;
2033	+	boolean validated = false;
2034	+	t.acquire(0);
2035	+	try {
2036	+	if (tabAt(tab, i) == f) {
2037	+	validated = true;
2038	+	splitTreeBin(nextTab, i, t);
2039	+	setTabAt(tab, i, fwd);
2040	+	}
2041	+	} finally {
2042	+	t.release(0);
2043	+	}
2044	+	if (!validated)
2045	+	continue;
2046	+	}
2047	+	}
2048	+	else if ((fh & LOCKED) == 0 && f.casHash(fh, fh|LOCKED)) {
2049	+	boolean validated = false;
2050	+	try {              // split to lo and hi lists; copying as needed
2051	+	if (tabAt(tab, i) == f) {
2052	+	validated = true;
2053	+	splitBin(nextTab, i, f);
2054	+	setTabAt(tab, i, fwd);
2055	+	}
2056	+	} finally {
2057	+	if (!f.casHash(fh | LOCKED, fh)) {
2058	+	f.hash = fh;
2059	+	synchronized (f) { f.notifyAll(); };
2060	+	}
2061	+	}
2062	+	if (!validated)
2063	+	continue;
2064	+	}
2065	+	else {
2066	+	if (buffer == null) // initialize buffer for revisits
2067	+	buffer = new int[TRANSFER_BUFFER_SIZE];
2068	+	if (bin < 0 && bufferIndex > 0) {
2069	+	int j = buffer[--bufferIndex];
2070	+	buffer[bufferIndex] = i;
2071	+	i = j;         // swap with another bin
2072	+	continue;
2073	+	}
2074	+	if (bin < 0 || nbuffered >= TRANSFER_BUFFER_SIZE) {
2075	+	f.tryAwaitLock(tab, i);
2076	+	continue;      // no other options -- block
2077	+	}
2078	+	if (rev == null)   // initialize reverse-forwarder
2079	+	rev = new Node(MOVED, tab, null, null);
2080	+	if (tabAt(tab, i) != f || (f.hash & LOCKED) == 0)
2081	+	continue;      // recheck before adding to list
2082	+	buffer[nbuffered++] = i;
2083	+	setTabAt(nextTab, i, rev);     // install place-holders
2084	+	setTabAt(nextTab, i + n, rev);
2085	+	}
2086
2087	+	if (bin > 0)
2088	+	i = --bin;
2089	+	else if (buffer != null && nbuffered > 0) {
2090	+	bin = -1;
2091	+	i = buffer[bufferIndex = --nbuffered];
2092	+	}
2093	+	else
2094	+	return nextTab;
2095	+	}
2096	+	}
2097
2098	<	/* ---------------- Public operations -------------- */
2098	>	/**
2099	>	* Splits a normal bin with list headed by e into lo and hi parts;
2100	>	* installs in given table.
2101	>	*/
2102	>	private static void splitBin(Node[] nextTab, int i, Node e) {
2103	>	int bit = nextTab.length >>> 1; // bit to split on
2104	>	int runBit = e.hash & bit;
2105	>	Node lastRun = e, lo = null, hi = null;
2106	>	for (Node p = e.next; p != null; p = p.next) {
2107	>	int b = p.hash & bit;
2108	>	if (b != runBit) {
2109	>	runBit = b;
2110	>	lastRun = p;
2111	>	}
2112	>	}
2113	>	if (runBit == 0)
2114	>	lo = lastRun;
2115	>	else
2116	>	hi = lastRun;
2117	>	for (Node p = e; p != lastRun; p = p.next) {
2118	>	int ph = p.hash & HASH_BITS;
2119	>	Object pk = p.key, pv = p.val;
2120	>	if ((ph & bit) == 0)
2121	>	lo = new Node(ph, pk, pv, lo);
2122	>	else
2123	>	hi = new Node(ph, pk, pv, hi);
2124	>	}
2125	>	setTabAt(nextTab, i, lo);
2126	>	setTabAt(nextTab, i + bit, hi);
2127	>	}
2128
2129		/**
2130	<	* Creates a new, empty map with the specified initial
566	<	* capacity, load factor and concurrency level.
567	<	*
568	<	* @param initialCapacity the initial capacity. The implementation
569	<	* performs internal sizing to accommodate this many elements.
570	<	* @param loadFactor  the load factor threshold, used to control resizing.
571	<	* Resizing may be performed when the average number of elements per
572	<	* bin exceeds this threshold.
573	<	* @param concurrencyLevel the estimated number of concurrently
574	<	* updating threads. The implementation performs internal sizing
575	<	* to try to accommodate this many threads.
576	<	* @throws IllegalArgumentException if the initial capacity is
577	<	* negative or the load factor or concurrencyLevel are
578	<	* nonpositive.
2130	>	* Splits a tree bin into lo and hi parts; installs in given table.
2131		*/
2132	<	public ConcurrentHashMap(int initialCapacity,
2133	<	float loadFactor, int concurrencyLevel) {
2134	<	if (!(loadFactor > 0) || initialCapacity < 0 || concurrencyLevel <= 0)
2135	<	throw new IllegalArgumentException();
2132	>	private static void splitTreeBin(Node[] nextTab, int i, TreeBin t) {
2133	>	int bit = nextTab.length >>> 1;
2134	>	TreeBin lt = new TreeBin();
2135	>	TreeBin ht = new TreeBin();
2136	>	int lc = 0, hc = 0;
2137	>	for (Node e = t.first; e != null; e = e.next) {
2138	>	int h = e.hash & HASH_BITS;
2139	>	Object k = e.key, v = e.val;
2140	>	if ((h & bit) == 0) {
2141	>	++lc;
2142	>	lt.putTreeNode(h, k, v);
2143	>	}
2144	>	else {
2145	>	++hc;
2146	>	ht.putTreeNode(h, k, v);
2147	>	}
2148	>	}
2149	>	Node ln, hn; // throw away trees if too small
2150	>	if (lc <= (TREE_THRESHOLD >>> 1)) {
2151	>	ln = null;
2152	>	for (Node p = lt.first; p != null; p = p.next)
2153	>	ln = new Node(p.hash, p.key, p.val, ln);
2154	>	}
2155	>	else
2156	>	ln = new Node(MOVED, lt, null, null);
2157	>	setTabAt(nextTab, i, ln);
2158	>	if (hc <= (TREE_THRESHOLD >>> 1)) {
2159	>	hn = null;
2160	>	for (Node p = ht.first; p != null; p = p.next)
2161	>	hn = new Node(p.hash, p.key, p.val, hn);
2162	>	}
2163	>	else
2164	>	hn = new Node(MOVED, ht, null, null);
2165	>	setTabAt(nextTab, i + bit, hn);
2166	>	}
2167
2168	<	if (concurrencyLevel > MAX_SEGMENTS)
2169	<	concurrencyLevel = MAX_SEGMENTS;
2168	>	/**
2169	>	* Implementation for clear. Steps through each bin, removing all
2170	>	* nodes.
2171	>	*/
2172	>	private final void internalClear() {
2173	>	long delta = 0L; // negative number of deletions
2174	>	int i = 0;
2175	>	Node[] tab = table;
2176	>	while (tab != null && i < tab.length) {
2177	>	int fh; Object fk;
2178	>	Node f = tabAt(tab, i);
2179	>	if (f == null)
2180	>	++i;
2181	>	else if ((fh = f.hash) == MOVED) {
2182	>	if ((fk = f.key) instanceof TreeBin) {
2183	>	TreeBin t = (TreeBin)fk;
2184	>	t.acquire(0);
2185	>	try {
2186	>	if (tabAt(tab, i) == f) {
2187	>	for (Node p = t.first; p != null; p = p.next) {
2188	>	if (p.val != null) { // (currently always true)
2189	>	p.val = null;
2190	>	--delta;
2191	>	}
2192	>	}
2193	>	t.first = null;
2194	>	t.root = null;
2195	>	++i;
2196	>	}
2197	>	} finally {
2198	>	t.release(0);
2199	>	}
2200	>	}
2201	>	else
2202	>	tab = (Node[])fk;
2203	>	}
2204	>	else if ((fh & LOCKED) != 0) {
2205	>	counter.add(delta); // opportunistically update count
2206	>	delta = 0L;
2207	>	f.tryAwaitLock(tab, i);
2208	>	}
2209	>	else if (f.casHash(fh, fh | LOCKED)) {
2210	>	try {
2211	>	if (tabAt(tab, i) == f) {
2212	>	for (Node e = f; e != null; e = e.next) {
2213	>	if (e.val != null) {  // (currently always true)
2214	>	e.val = null;
2215	>	--delta;
2216	>	}
2217	>	}
2218	>	setTabAt(tab, i, null);
2219	>	++i;
2220	>	}
2221	>	} finally {
2222	>	if (!f.casHash(fh | LOCKED, fh)) {
2223	>	f.hash = fh;
2224	>	synchronized (f) { f.notifyAll(); };
2225	>	}
2226	>	}
2227	>	}
2228	>	}
2229	>	if (delta != 0)
2230	>	counter.add(delta);
2231	>	}
2232
2233	<	// Find power-of-two sizes best matching arguments
589	<	int sshift = 0;
590	<	int ssize = 1;
591	<	while (ssize < concurrencyLevel) {
592	<	++sshift;
593	<	ssize <<= 1;
594	<	}
595	<	segmentShift = 32 - sshift;
596	<	segmentMask = ssize - 1;
597	<	this.segments = Segment.newArray(ssize);
598	<
599	<	if (initialCapacity > MAXIMUM_CAPACITY)
600	<	initialCapacity = MAXIMUM_CAPACITY;
601	<	int c = initialCapacity / ssize;
602	<	if (c * ssize < initialCapacity)
603	<	++c;
604	<	int cap = 1;
605	<	while (cap < c)
606	<	cap <<= 1;
2233	>	/* ----------------Table Traversal -------------- */
2234
2235	<	for (int i = 0; i < this.segments.length; ++i)
2236	<	this.segments[i] = new Segment<K,V>(cap, loadFactor);
2235	>	/**
2236	>	* Encapsulates traversal for methods such as containsValue; also
2237	>	* serves as a base class for other iterators and bulk tasks.
2238	>	*
2239	>	* At each step, the iterator snapshots the key ("nextKey") and
2240	>	* value ("nextVal") of a valid node (i.e., one that, at point of
2241	>	* snapshot, has a non-null user value). Because val fields can
2242	>	* change (including to null, indicating deletion), field nextVal
2243	>	* might not be accurate at point of use, but still maintains the
2244	>	* weak consistency property of holding a value that was once
2245	>	* valid.
2246	>	*
2247	>	* Internal traversals directly access these fields, as in:
2248	>	* {@code while (it.advance() != null) { process(it.nextKey); }}
2249	>	*
2250	>	* Exported iterators must track whether the iterator has advanced
2251	>	* (in hasNext vs next) (by setting/checking/nulling field
2252	>	* nextVal), and then extract key, value, or key-value pairs as
2253	>	* return values of next().
2254	>	*
2255	>	* The iterator visits once each still-valid node that was
2256	>	* reachable upon iterator construction. It might miss some that
2257	>	* were added to a bin after the bin was visited, which is OK wrt
2258	>	* consistency guarantees. Maintaining this property in the face
2259	>	* of possible ongoing resizes requires a fair amount of
2260	>	* bookkeeping state that is difficult to optimize away amidst
2261	>	* volatile accesses.  Even so, traversal maintains reasonable
2262	>	* throughput.
2263	>	*
2264	>	* Normally, iteration proceeds bin-by-bin traversing lists.
2265	>	* However, if the table has been resized, then all future steps
2266	>	* must traverse both the bin at the current index as well as at
2267	>	* (index + baseSize); and so on for further resizings. To
2268	>	* paranoically cope with potential sharing by users of iterators
2269	>	* across threads, iteration terminates if a bounds checks fails
2270	>	* for a table read.
2271	>	*
2272	>	* This class extends ForkJoinTask to streamline parallel
2273	>	* iteration in bulk operations (see BulkTask). This adds only an
2274	>	* int of space overhead, which is close enough to negligible in
2275	>	* cases where it is not needed to not worry about it.  Because
2276	>	* ForkJoinTask is Serializable, but iterators need not be, we
2277	>	* need to add warning suppressions.
2278	>	*/
2279	>	@SuppressWarnings("serial") static class Traverser<K,V,R> extends ForkJoinTask<R> {
2280	>	final ConcurrentHashMap<K, V> map;
2281	>	Node next;           // the next entry to use
2282	>	Node last;           // the last entry used
2283	>	Object nextKey;      // cached key field of next
2284	>	Object nextVal;      // cached val field of next
2285	>	Node[] tab;          // current table; updated if resized
2286	>	int index;           // index of bin to use next
2287	>	int baseIndex;       // current index of initial table
2288	>	int baseLimit;       // index bound for initial table
2289	>	int baseSize;        // initial table size
2290	>
2291	>	/** Creates iterator for all entries in the table. */
2292	>	Traverser(ConcurrentHashMap<K, V> map) {
2293	>	this.map = map;
2294	>	}
2295	>
2296	>	/** Creates iterator for split() methods */
2297	>	Traverser(Traverser<K,V,?> it) {
2298	>	ConcurrentHashMap<K, V> m; Node[] t;
2299	>	if ((m = this.map = it.map) == null)
2300	>	t = null;
2301	>	else if ((t = it.tab) == null && // force parent tab initialization
2302	>	(t = it.tab = m.table) != null)
2303	>	it.baseLimit = it.baseSize = t.length;
2304	>	this.tab = t;
2305	>	this.baseSize = it.baseSize;
2306	>	it.baseLimit = this.index = this.baseIndex =
2307	>	((this.baseLimit = it.baseLimit) + it.baseIndex + 1) >>> 1;
2308	>	}
2309	>
2310	>	/**
2311	>	* Advances next; returns nextVal or null if terminated.
2312	>	* See above for explanation.
2313	>	*/
2314	>	final Object advance() {
2315	>	Node e = last = next;
2316	>	Object ev = null;
2317	>	outer: do {
2318	>	if (e != null)                  // advance past used/skipped node
2319	>	e = e.next;
2320	>	while (e == null) {             // get to next non-null bin
2321	>	ConcurrentHashMap<K, V> m;
2322	>	Node[] t; int b, i, n; Object ek; // checks must use locals
2323	>	if ((t = tab) != null)
2324	>	n = t.length;
2325	>	else if ((m = map) != null && (t = tab = m.table) != null)
2326	>	n = baseLimit = baseSize = t.length;
2327	>	else
2328	>	break outer;
2329	>	if ((b = baseIndex) >= baseLimit ||
2330	>	(i = index) < 0 || i >= n)
2331	>	break outer;
2332	>	if ((e = tabAt(t, i)) != null && e.hash == MOVED) {
2333	>	if ((ek = e.key) instanceof TreeBin)
2334	>	e = ((TreeBin)ek).first;
2335	>	else {
2336	>	tab = (Node[])ek;
2337	>	continue;           // restarts due to null val
2338	>	}
2339	>	}                           // visit upper slots if present
2340	>	index = (i += baseSize) < n ? i : (baseIndex = b + 1);
2341	>	}
2342	>	nextKey = e.key;
2343	>	} while ((ev = e.val) == null);    // skip deleted or special nodes
2344	>	next = e;
2345	>	return nextVal = ev;
2346	>	}
2347	>
2348	>	public final void remove() {
2349	>	if (nextVal == null && last == null)
2350	>	advance();
2351	>	Node e = last;
2352	>	if (e == null)
2353	>	throw new IllegalStateException();
2354	>	last = null;
2355	>	map.remove(e.key);
2356	>	}
2357	>
2358	>	public final boolean hasNext() {
2359	>	return nextVal != null || advance() != null;
2360	>	}
2361	>
2362	>	public final boolean hasMoreElements() { return hasNext(); }
2363	>	public final void setRawResult(Object x) { }
2364	>	public R getRawResult() { return null; }
2365	>	public boolean exec() { return true; }
2366		}
2367
2368	+	/* ---------------- Public operations -------------- */
2369	+
2370		/**
2371	<	* Creates a new, empty map with the specified initial capacity
2372	<	* and load factor and with the default concurrencyLevel (16).
2371	>	* Creates a new, empty map with the default initial table size (16).
2372	>	*/
2373	>	public ConcurrentHashMap() {
2374	>	this.counter = new LongAdder();
2375	>	}
2376	>
2377	>	/**
2378	>	* Creates a new, empty map with an initial table size
2379	>	* accommodating the specified number of elements without the need
2380	>	* to dynamically resize.
2381		*
2382		* @param initialCapacity The implementation performs internal
2383		* sizing to accommodate this many elements.
2384	<	* @param loadFactor  the load factor threshold, used to control resizing.
2385	<	* Resizing may be performed when the average number of elements per
2386	<	* bin exceeds this threshold.
2384	>	* @throws IllegalArgumentException if the initial capacity of
2385	>	* elements is negative
2386	>	*/
2387	>	public ConcurrentHashMap(int initialCapacity) {
2388	>	if (initialCapacity < 0)
2389	>	throw new IllegalArgumentException();
2390	>	int cap = ((initialCapacity >= (MAXIMUM_CAPACITY >>> 1)) ?
2391	>	MAXIMUM_CAPACITY :
2392	>	tableSizeFor(initialCapacity + (initialCapacity >>> 1) + 1));
2393	>	this.counter = new LongAdder();
2394	>	this.sizeCtl = cap;
2395	>	}
2396	>
2397	>	/**
2398	>	* Creates a new map with the same mappings as the given map.
2399	>	*
2400	>	* @param m the map
2401	>	*/
2402	>	public ConcurrentHashMap(Map<? extends K, ? extends V> m) {
2403	>	this.counter = new LongAdder();
2404	>	this.sizeCtl = DEFAULT_CAPACITY;
2405	>	internalPutAll(m);
2406	>	}
2407	>
2408	>	/**
2409	>	* Creates a new, empty map with an initial table size based on
2410	>	* the given number of elements ({@code initialCapacity}) and
2411	>	* initial table density ({@code loadFactor}).
2412	>	*
2413	>	* @param initialCapacity the initial capacity. The implementation
2414	>	* performs internal sizing to accommodate this many elements,
2415	>	* given the specified load factor.
2416	>	* @param loadFactor the load factor (table density) for
2417	>	* establishing the initial table size
2418		* @throws IllegalArgumentException if the initial capacity of
2419		* elements is negative or the load factor is nonpositive
2420		*
2421		* @since 1.6
2422		*/
2423		public ConcurrentHashMap(int initialCapacity, float loadFactor) {
2424	<	this(initialCapacity, loadFactor, DEFAULT_CONCURRENCY_LEVEL);
2424	>	this(initialCapacity, loadFactor, 1);
2425		}
2426
2427		/**
2428	<	* Creates a new, empty map with the specified initial capacity,
2429	<	* and with default load factor (0.75) and concurrencyLevel (16).
2428	>	* Creates a new, empty map with an initial table size based on
2429	>	* the given number of elements ({@code initialCapacity}), table
2430	>	* density ({@code loadFactor}), and number of concurrently
2431	>	* updating threads ({@code concurrencyLevel}).
2432		*
2433		* @param initialCapacity the initial capacity. The implementation
2434	<	* performs internal sizing to accommodate this many elements.
2435	<	* @throws IllegalArgumentException if the initial capacity of
2436	<	* elements is negative.
2434	>	* performs internal sizing to accommodate this many elements,
2435	>	* given the specified load factor.
2436	>	* @param loadFactor the load factor (table density) for
2437	>	* establishing the initial table size
2438	>	* @param concurrencyLevel the estimated number of concurrently
2439	>	* updating threads. The implementation may use this value as
2440	>	* a sizing hint.
2441	>	* @throws IllegalArgumentException if the initial capacity is
2442	>	* negative or the load factor or concurrencyLevel are
2443	>	* nonpositive
2444		*/
2445	<	public ConcurrentHashMap(int initialCapacity) {
2446	<	this(initialCapacity, DEFAULT_LOAD_FACTOR, DEFAULT_CONCURRENCY_LEVEL);
2445	>	public ConcurrentHashMap(int initialCapacity,
2446	>	float loadFactor, int concurrencyLevel) {
2447	>	if (!(loadFactor > 0.0f) || initialCapacity < 0 || concurrencyLevel <= 0)
2448	>	throw new IllegalArgumentException();
2449	>	if (initialCapacity < concurrencyLevel)   // Use at least as many bins
2450	>	initialCapacity = concurrencyLevel;   // as estimated threads
2451	>	long size = (long)(1.0 + (long)initialCapacity / loadFactor);
2452	>	int cap = (size >= (long)MAXIMUM_CAPACITY) ?
2453	>	MAXIMUM_CAPACITY : tableSizeFor((int)size);
2454	>	this.counter = new LongAdder();
2455	>	this.sizeCtl = cap;
2456		}
2457
2458		/**
2459	<	* Creates a new, empty map with a default initial capacity (16),
645	<	* load factor (0.75) and concurrencyLevel (16).
2459	>	* {@inheritDoc}
2460		*/
2461	<	public ConcurrentHashMap() {
2462	<	this(DEFAULT_INITIAL_CAPACITY, DEFAULT_LOAD_FACTOR, DEFAULT_CONCURRENCY_LEVEL);
2461	>	public boolean isEmpty() {
2462	>	return counter.sum() <= 0L; // ignore transient negative values
2463		}
2464
2465		/**
2466	<	* Creates a new map with the same mappings as the given map.
653	<	* The map is created with a capacity of 1.5 times the number
654	<	* of mappings in the given map or 16 (whichever is greater),
655	<	* and a default load factor (0.75) and concurrencyLevel (16).
656	<	*
657	<	* @param m the map
2466	>	* {@inheritDoc}
2467		*/
2468	<	public ConcurrentHashMap(Map<? extends K, ? extends V> m) {
2469	<	this(Math.max((int) (m.size() / DEFAULT_LOAD_FACTOR) + 1,
2470	<	DEFAULT_INITIAL_CAPACITY),
2471	<	DEFAULT_LOAD_FACTOR, DEFAULT_CONCURRENCY_LEVEL);
2472	<	putAll(m);
2468	>	public int size() {
2469	>	long n = counter.sum();
2470	>	return ((n < 0L) ? 0 :
2471	>	(n > (long)Integer.MAX_VALUE) ? Integer.MAX_VALUE :
2472	>	(int)n);
2473		}
2474
2475		/**
2476	<	* Returns <tt>true</tt> if this map contains no key-value mappings.
2476	>	* Returns the number of mappings. This method should be used
2477	>	* instead of {@link #size} because a ConcurrentHashMap may
2478	>	* contain more mappings than can be represented as an int. The
2479	>	* value returned is a snapshot; the actual count may differ if
2480	>	* there are ongoing concurrent insertions or removals.
2481		*
2482	<	* @return <tt>true</tt> if this map contains no key-value mappings
2482	>	* @return the number of mappings
2483		*/
2484	<	public boolean isEmpty() {
2485	<	final Segment<K,V>[] segments = this.segments;
2486	<	/*
674	<	* We keep track of per-segment modCounts to avoid ABA
675	<	* problems in which an element in one segment was added and
676	<	* in another removed during traversal, in which case the
677	<	* table was never actually empty at any point. Note the
678	<	* similar use of modCounts in the size() and containsValue()
679	<	* methods, which are the only other methods also susceptible
680	<	* to ABA problems.
681	<	*/
682	<	int[] mc = new int[segments.length];
683	<	int mcsum = 0;
684	<	for (int i = 0; i < segments.length; ++i) {
685	<	if (segments[i].count != 0)
686	<	return false;
687	<	else
688	<	mcsum += mc[i] = segments[i].modCount;
689	<	}
690	<	// If mcsum happens to be zero, then we know we got a snapshot
691	<	// before any modifications at all were made.  This is
692	<	// probably common enough to bother tracking.
693	<	if (mcsum != 0) {
694	<	for (int i = 0; i < segments.length; ++i) {
695	<	if (segments[i].count != 0 ||
696	<	mc[i] != segments[i].modCount)
697	<	return false;
698	<	}
699	<	}
700	<	return true;
2484	>	public long mappingCount() {
2485	>	long n = counter.sum();
2486	>	return (n < 0L) ? 0L : n; // ignore transient negative values
2487		}
2488
2489		/**
2490	<	* Returns the number of key-value mappings in this map.  If the
2491	<	* map contains more than <tt>Integer.MAX_VALUE</tt> elements, returns
2492	<	* <tt>Integer.MAX_VALUE</tt>.
2490	>	* Returns the value to which the specified key is mapped,
2491	>	* or {@code null} if this map contains no mapping for the key.
2492	>	*
2493	>	* <p>More formally, if this map contains a mapping from a key
2494	>	* {@code k} to a value {@code v} such that {@code key.equals(k)},
2495	>	* then this method returns {@code v}; otherwise it returns
2496	>	* {@code null}.  (There can be at most one such mapping.)
2497		*
2498	<	* @return the number of key-value mappings in this map
2498	>	* @throws NullPointerException if the specified key is null
2499		*/
2500	<	public int size() {
2501	<	final Segment<K,V>[] segments = this.segments;
2502	<	long sum = 0;
2503	<	long check = 0;
714	<	int[] mc = new int[segments.length];
715	<	// Try a few times to get accurate count. On failure due to
716	<	// continuous async changes in table, resort to locking.
717	<	for (int k = 0; k < RETRIES_BEFORE_LOCK; ++k) {
718	<	check = 0;
719	<	sum = 0;
720	<	int mcsum = 0;
721	<	for (int i = 0; i < segments.length; ++i) {
722	<	sum += segments[i].count;
723	<	mcsum += mc[i] = segments[i].modCount;
724	<	}
725	<	if (mcsum != 0) {
726	<	for (int i = 0; i < segments.length; ++i) {
727	<	check += segments[i].count;
728	<	if (mc[i] != segments[i].modCount) {
729	<	check = -1; // force retry
730	<	break;
731	<	}
732	<	}
733	<	}
734	<	if (check == sum)
735	<	break;
736	<	}
737	<	if (check != sum) { // Resort to locking all segments
738	<	sum = 0;
739	<	for (int i = 0; i < segments.length; ++i)
740	<	segments[i].lock();
741	<	for (int i = 0; i < segments.length; ++i)
742	<	sum += segments[i].count;
743	<	for (int i = 0; i < segments.length; ++i)
744	<	segments[i].unlock();
745	<	}
746	<	if (sum > Integer.MAX_VALUE)
747	<	return Integer.MAX_VALUE;
748	<	else
749	<	return (int)sum;
2500	>	@SuppressWarnings("unchecked") public V get(Object key) {
2501	>	if (key == null)
2502	>	throw new NullPointerException();
2503	>	return (V)internalGet(key);
2504		}
2505
2506		/**
2507	<	* Returns the value to which this map maps the specified key, or
2508	<	* <tt>null</tt> if the map contains no mapping for the key.
2507	>	* Returns the value to which the specified key is mapped,
2508	>	* or the given defaultValue if this map contains no mapping for the key.
2509		*
2510	<	* @param key key whose associated value is to be returned
2511	<	* @return the value to which this map maps the specified key, or
2512	<	*         <tt>null</tt> if the map contains no mapping for the key
2510	>	* @param key the key
2511	>	* @param defaultValue the value to return if this map contains
2512	>	* no mapping for the given key
2513	>	* @return the mapping for the key, if present; else the defaultValue
2514		* @throws NullPointerException if the specified key is null
2515		*/
2516	<	public V get(Object key) {
2517	<	int hash = hash(key); // throws NullPointerException if key null
2518	<	return segmentFor(hash).get(key, hash);
2516	>	@SuppressWarnings("unchecked") public V getValueOrDefault(Object key, V defaultValue) {
2517	>	if (key == null)
2518	>	throw new NullPointerException();
2519	>	V v = (V) internalGet(key);
2520	>	return v == null ? defaultValue : v;
2521		}
2522
2523		/**
2524		* Tests if the specified object is a key in this table.
2525		*
2526		* @param  key   possible key
2527	<	* @return <tt>true</tt> if and only if the specified object
2527	>	* @return {@code true} if and only if the specified object
2528		*         is a key in this table, as determined by the
2529	<	*         <tt>equals</tt> method; <tt>false</tt> otherwise.
2529	>	*         {@code equals} method; {@code false} otherwise
2530		* @throws NullPointerException if the specified key is null
2531		*/
2532		public boolean containsKey(Object key) {
2533	<	int hash = hash(key); // throws NullPointerException if key null
2534	<	return segmentFor(hash).containsKey(key, hash);
2533	>	if (key == null)
2534	>	throw new NullPointerException();
2535	>	return internalGet(key) != null;
2536		}
2537
2538		/**
2539	<	* Returns <tt>true</tt> if this map maps one or more keys to the
2540	<	* specified value. Note: This method requires a full internal
2541	<	* traversal of the hash table, and so is much slower than
784	<	* method <tt>containsKey</tt>.
2539	>	* Returns {@code true} if this map maps one or more keys to the
2540	>	* specified value. Note: This method may require a full traversal
2541	>	* of the map, and is much slower than method {@code containsKey}.
2542		*
2543		* @param value value whose presence in this map is to be tested
2544	<	* @return <tt>true</tt> if this map maps one or more keys to the
2544	>	* @return {@code true} if this map maps one or more keys to the
2545		*         specified value
2546		* @throws NullPointerException if the specified value is null
2547		*/
2548		public boolean containsValue(Object value) {
2549		if (value == null)
2550		throw new NullPointerException();
2551	<
2552	<	// See explanation of modCount use above
2553	<
2554	<	final Segment<K,V>[] segments = this.segments;
2555	<	int[] mc = new int[segments.length];
799	<
800	<	// Try a few times without locking
801	<	for (int k = 0; k < RETRIES_BEFORE_LOCK; ++k) {
802	<	int sum = 0;
803	<	int mcsum = 0;
804	<	for (int i = 0; i < segments.length; ++i) {
805	<	int c = segments[i].count;
806	<	mcsum += mc[i] = segments[i].modCount;
807	<	if (segments[i].containsValue(value))
808	<	return true;
809	<	}
810	<	boolean cleanSweep = true;
811	<	if (mcsum != 0) {
812	<	for (int i = 0; i < segments.length; ++i) {
813	<	int c = segments[i].count;
814	<	if (mc[i] != segments[i].modCount) {
815	<	cleanSweep = false;
816	<	break;
817	<	}
818	<	}
819	<	}
820	<	if (cleanSweep)
821	<	return false;
822	<	}
823	<	// Resort to locking all segments
824	<	for (int i = 0; i < segments.length; ++i)
825	<	segments[i].lock();
826	<	boolean found = false;
827	<	try {
828	<	for (int i = 0; i < segments.length; ++i) {
829	<	if (segments[i].containsValue(value)) {
830	<	found = true;
831	<	break;
832	<	}
833	<	}
834	<	} finally {
835	<	for (int i = 0; i < segments.length; ++i)
836	<	segments[i].unlock();
2551	>	Object v;
2552	>	Traverser<K,V,Object> it = new Traverser<K,V,Object>(this);
2553	>	while ((v = it.advance()) != null) {
2554	>	if (v == value || value.equals(v))
2555	>	return true;
2556		}
2557	<	return found;
2557	>	return false;
2558		}
2559
2560		/**
#	Line 845 | Line 2564 | public class ConcurrentHashMap<K, V> ext
2564		* full compatibility with class {@link java.util.Hashtable},
2565		* which supported this method prior to introduction of the
2566		* Java Collections framework.
2567	<
2567	>	*
2568		* @param  value a value to search for
2569	<	* @return <tt>true</tt> if and only if some key maps to the
2570	<	*         <tt>value</tt> argument in this table as
2571	<	*         determined by the <tt>equals</tt> method;
2572	<	*         <tt>false</tt> otherwise
2569	>	* @return {@code true} if and only if some key maps to the
2570	>	*         {@code value} argument in this table as
2571	>	*         determined by the {@code equals} method;
2572	>	*         {@code false} otherwise
2573		* @throws NullPointerException if the specified value is null
2574		*/
2575		public boolean contains(Object value) {
#	Line 861 | Line 2580 | public class ConcurrentHashMap<K, V> ext
2580		* Maps the specified key to the specified value in this table.
2581		* Neither the key nor the value can be null.
2582		*
2583	<	* <p> The value can be retrieved by calling the <tt>get</tt> method
2583	>	* <p> The value can be retrieved by calling the {@code get} method
2584		* with a key that is equal to the original key.
2585		*
2586		* @param key key with which the specified value is to be associated
2587		* @param value value to be associated with the specified key
2588	<	* @return the previous value associated with <tt>key</tt>, or
2589	<	*         <tt>null</tt> if there was no mapping for <tt>key</tt>
2588	>	* @return the previous value associated with {@code key}, or
2589	>	*         {@code null} if there was no mapping for {@code key}
2590		* @throws NullPointerException if the specified key or value is null
2591		*/
2592	<	public V put(K key, V value) {
2593	<	if (value == null)
2592	>	@SuppressWarnings("unchecked") public V put(K key, V value) {
2593	>	if (key == null || value == null)
2594		throw new NullPointerException();
2595	<	int hash = hash(key);
877	<	return segmentFor(hash).put(key, hash, value, false);
2595	>	return (V)internalPut(key, value);
2596		}
2597
2598		/**
2599		* {@inheritDoc}
2600		*
2601		* @return the previous value associated with the specified key,
2602	<	*         or <tt>null</tt> if there was no mapping for the key
2602	>	*         or {@code null} if there was no mapping for the key
2603		* @throws NullPointerException if the specified key or value is null
2604		*/
2605	<	public V putIfAbsent(K key, V value) {
2606	<	if (value == null)
2605	>	@SuppressWarnings("unchecked") public V putIfAbsent(K key, V value) {
2606	>	if (key == null || value == null)
2607		throw new NullPointerException();
2608	<	int hash = hash(key);
891	<	return segmentFor(hash).put(key, hash, value, true);
2608	>	return (V)internalPutIfAbsent(key, value);
2609		}
2610
2611		/**
#	Line 899 | Line 2616 | public class ConcurrentHashMap<K, V> ext
2616		* @param m mappings to be stored in this map
2617		*/
2618		public void putAll(Map<? extends K, ? extends V> m) {
2619	<	for (Iterator<? extends Map.Entry<? extends K, ? extends V>> it = (Iterator<? extends Map.Entry<? extends K, ? extends V>>) m.entrySet().iterator(); it.hasNext(); ) {
2620	<	Entry<? extends K, ? extends V> e = it.next();
2621	<	put(e.getKey(), e.getValue());
2622	<	}
2619	>	internalPutAll(m);
2620	>	}
2621	>
2622	>	/**
2623	>	* If the specified key is not already associated with a value,
2624	>	* computes its value using the given mappingFunction and enters
2625	>	* it into the map unless null.  This is equivalent to
2626	>	* <pre> {@code
2627	>	* if (map.containsKey(key))
2628	>	*   return map.get(key);
2629	>	* value = mappingFunction.apply(key);
2630	>	* if (value != null)
2631	>	*   map.put(key, value);
2632	>	* return value;}</pre>
2633	>	*
2634	>	* except that the action is performed atomically.  If the
2635	>	* function returns {@code null} no mapping is recorded. If the
2636	>	* function itself throws an (unchecked) exception, the exception
2637	>	* is rethrown to its caller, and no mapping is recorded.  Some
2638	>	* attempted update operations on this map by other threads may be
2639	>	* blocked while computation is in progress, so the computation
2640	>	* should be short and simple, and must not attempt to update any
2641	>	* other mappings of this Map. The most appropriate usage is to
2642	>	* construct a new object serving as an initial mapped value, or
2643	>	* memoized result, as in:
2644	>	*
2645	>	*  <pre> {@code
2646	>	* map.computeIfAbsent(key, new Fun<K, V>() {
2647	>	*   public V map(K k) { return new Value(f(k)); }});}</pre>
2648	>	*
2649	>	* @param key key with which the specified value is to be associated
2650	>	* @param mappingFunction the function to compute a value
2651	>	* @return the current (existing or computed) value associated with
2652	>	*         the specified key, or null if the computed value is null
2653	>	* @throws NullPointerException if the specified key or mappingFunction
2654	>	*         is null
2655	>	* @throws IllegalStateException if the computation detectably
2656	>	*         attempts a recursive update to this map that would
2657	>	*         otherwise never complete
2658	>	* @throws RuntimeException or Error if the mappingFunction does so,
2659	>	*         in which case the mapping is left unestablished
2660	>	*/
2661	>	@SuppressWarnings("unchecked") public V computeIfAbsent
2662	>	(K key, Fun<? super K, ? extends V> mappingFunction) {
2663	>	if (key == null || mappingFunction == null)
2664	>	throw new NullPointerException();
2665	>	return (V)internalComputeIfAbsent(key, mappingFunction);
2666	>	}
2667	>
2668	>	/**
2669	>	* If the given key is present, computes a new mapping value given a key and
2670	>	* its current mapped value. This is equivalent to
2671	>	*  <pre> {@code
2672	>	*   if (map.containsKey(key)) {
2673	>	*     value = remappingFunction.apply(key, map.get(key));
2674	>	*     if (value != null)
2675	>	*       map.put(key, value);
2676	>	*     else
2677	>	*       map.remove(key);
2678	>	*   }
2679	>	* }</pre>
2680	>	*
2681	>	* except that the action is performed atomically.  If the
2682	>	* function returns {@code null}, the mapping is removed.  If the
2683	>	* function itself throws an (unchecked) exception, the exception
2684	>	* is rethrown to its caller, and the current mapping is left
2685	>	* unchanged.  Some attempted update operations on this map by
2686	>	* other threads may be blocked while computation is in progress,
2687	>	* so the computation should be short and simple, and must not
2688	>	* attempt to update any other mappings of this Map. For example,
2689	>	* to either create or append new messages to a value mapping:
2690	>	*
2691	>	* @param key key with which the specified value is to be associated
2692	>	* @param remappingFunction the function to compute a value
2693	>	* @return the new value associated with the specified key, or null if none
2694	>	* @throws NullPointerException if the specified key or remappingFunction
2695	>	*         is null
2696	>	* @throws IllegalStateException if the computation detectably
2697	>	*         attempts a recursive update to this map that would
2698	>	*         otherwise never complete
2699	>	* @throws RuntimeException or Error if the remappingFunction does so,
2700	>	*         in which case the mapping is unchanged
2701	>	*/
2702	>	@SuppressWarnings("unchecked") public V computeIfPresent
2703	>	(K key, BiFun<? super K, ? super V, ? extends V> remappingFunction) {
2704	>	if (key == null || remappingFunction == null)
2705	>	throw new NullPointerException();
2706	>	return (V)internalCompute(key, true, remappingFunction);
2707	>	}
2708	>
2709	>	/**
2710	>	* Computes a new mapping value given a key and
2711	>	* its current mapped value (or {@code null} if there is no current
2712	>	* mapping). This is equivalent to
2713	>	*  <pre> {@code
2714	>	*   value = remappingFunction.apply(key, map.get(key));
2715	>	*   if (value != null)
2716	>	*     map.put(key, value);
2717	>	*   else
2718	>	*     map.remove(key);
2719	>	* }</pre>
2720	>	*
2721	>	* except that the action is performed atomically.  If the
2722	>	* function returns {@code null}, the mapping is removed.  If the
2723	>	* function itself throws an (unchecked) exception, the exception
2724	>	* is rethrown to its caller, and the current mapping is left
2725	>	* unchanged.  Some attempted update operations on this map by
2726	>	* other threads may be blocked while computation is in progress,
2727	>	* so the computation should be short and simple, and must not
2728	>	* attempt to update any other mappings of this Map. For example,
2729	>	* to either create or append new messages to a value mapping:
2730	>	*
2731	>	* <pre> {@code
2732	>	* Map<Key, String> map = ...;
2733	>	* final String msg = ...;
2734	>	* map.compute(key, new BiFun<Key, String, String>() {
2735	>	*   public String apply(Key k, String v) {
2736	>	*    return (v == null) ? msg : v + msg;});}}</pre>
2737	>	*
2738	>	* @param key key with which the specified value is to be associated
2739	>	* @param remappingFunction the function to compute a value
2740	>	* @return the new value associated with the specified key, or null if none
2741	>	* @throws NullPointerException if the specified key or remappingFunction
2742	>	*         is null
2743	>	* @throws IllegalStateException if the computation detectably
2744	>	*         attempts a recursive update to this map that would
2745	>	*         otherwise never complete
2746	>	* @throws RuntimeException or Error if the remappingFunction does so,
2747	>	*         in which case the mapping is unchanged
2748	>	*/
2749	>	@SuppressWarnings("unchecked") public V compute
2750	>	(K key, BiFun<? super K, ? super V, ? extends V> remappingFunction) {
2751	>	if (key == null || remappingFunction == null)
2752	>	throw new NullPointerException();
2753	>	return (V)internalCompute(key, false, remappingFunction);
2754	>	}
2755	>
2756	>	/**
2757	>	* If the specified key is not already associated
2758	>	* with a value, associate it with the given value.
2759	>	* Otherwise, replace the value with the results of
2760	>	* the given remapping function. This is equivalent to:
2761	>	*  <pre> {@code
2762	>	*   if (!map.containsKey(key))
2763	>	*     map.put(value);
2764	>	*   else {
2765	>	*     newValue = remappingFunction.apply(map.get(key), value);
2766	>	*     if (value != null)
2767	>	*       map.put(key, value);
2768	>	*     else
2769	>	*       map.remove(key);
2770	>	*   }
2771	>	* }</pre>
2772	>	* except that the action is performed atomically.  If the
2773	>	* function returns {@code null}, the mapping is removed.  If the
2774	>	* function itself throws an (unchecked) exception, the exception
2775	>	* is rethrown to its caller, and the current mapping is left
2776	>	* unchanged.  Some attempted update operations on this map by
2777	>	* other threads may be blocked while computation is in progress,
2778	>	* so the computation should be short and simple, and must not
2779	>	* attempt to update any other mappings of this Map.
2780	>	*/
2781	>	@SuppressWarnings("unchecked") public V merge
2782	>	(K key, V value, BiFun<? super V, ? super V, ? extends V> remappingFunction) {
2783	>	if (key == null || value == null || remappingFunction == null)
2784	>	throw new NullPointerException();
2785	>	return (V)internalMerge(key, value, remappingFunction);
2786		}
2787
2788		/**
#	Line 910 | Line 2790 | public class ConcurrentHashMap<K, V> ext
2790		* This method does nothing if the key is not in the map.
2791		*
2792		* @param  key the key that needs to be removed
2793	<	* @return the previous value associated with <tt>key</tt>, or
2794	<	*         <tt>null</tt> if there was no mapping for <tt>key</tt>.
2793	>	* @return the previous value associated with {@code key}, or
2794	>	*         {@code null} if there was no mapping for {@code key}
2795		* @throws NullPointerException if the specified key is null
2796		*/
2797	<	public V remove(Object key) {
2798	<	int hash = hash(key);
2799	<	return segmentFor(hash).remove(key, hash, null);
2797	>	@SuppressWarnings("unchecked") public V remove(Object key) {
2798	>	if (key == null)
2799	>	throw new NullPointerException();
2800	>	return (V)internalReplace(key, null, null);
2801		}
2802
2803		/**
#	Line 925 | Line 2806 | public class ConcurrentHashMap<K, V> ext
2806		* @throws NullPointerException if the specified key is null
2807		*/
2808		public boolean remove(Object key, Object value) {
2809	+	if (key == null)
2810	+	throw new NullPointerException();
2811		if (value == null)
2812		return false;
2813	<	int hash = hash(key);
931	<	return segmentFor(hash).remove(key, hash, value) != null;
2813	>	return internalReplace(key, null, value) != null;
2814		}
2815
2816		/**
#	Line 937 | Line 2819 | public class ConcurrentHashMap<K, V> ext
2819		* @throws NullPointerException if any of the arguments are null
2820		*/
2821		public boolean replace(K key, V oldValue, V newValue) {
2822	<	if (oldValue == null || newValue == null)
2822	>	if (key == null || oldValue == null || newValue == null)
2823		throw new NullPointerException();
2824	<	int hash = hash(key);
943	<	return segmentFor(hash).replace(key, hash, oldValue, newValue);
2824	>	return internalReplace(key, newValue, oldValue) != null;
2825		}
2826
2827		/**
2828		* {@inheritDoc}
2829		*
2830		* @return the previous value associated with the specified key,
2831	<	*         or <tt>null</tt> if there was no mapping for the key
2831	>	*         or {@code null} if there was no mapping for the key
2832		* @throws NullPointerException if the specified key or value is null
2833		*/
2834	<	public V replace(K key, V value) {
2835	<	if (value == null)
2834	>	@SuppressWarnings("unchecked") public V replace(K key, V value) {
2835	>	if (key == null || value == null)
2836		throw new NullPointerException();
2837	<	int hash = hash(key);
957	<	return segmentFor(hash).replace(key, hash, value);
2837	>	return (V)internalReplace(key, value, null);
2838		}
2839
2840		/**
2841		* Removes all of the mappings from this map.
2842		*/
2843		public void clear() {
2844	<	for (int i = 0; i < segments.length; ++i)
965	<	segments[i].clear();
2844	>	internalClear();
2845		}
2846
2847		/**
#	Line 970 | Line 2849 | public class ConcurrentHashMap<K, V> ext
2849		* The set is backed by the map, so changes to the map are
2850		* reflected in the set, and vice-versa.  The set supports element
2851		* removal, which removes the corresponding mapping from this map,
2852	<	* via the <tt>Iterator.remove</tt>, <tt>Set.remove</tt>,
2853	<	* <tt>removeAll</tt>, <tt>retainAll</tt>, and <tt>clear</tt>
2854	<	* operations.  It does not support the <tt>add</tt> or
2855	<	* <tt>addAll</tt> operations.
2852	>	* via the {@code Iterator.remove}, {@code Set.remove},
2853	>	* {@code removeAll}, {@code retainAll}, and {@code clear}
2854	>	* operations.  It does not support the {@code add} or
2855	>	* {@code addAll} operations.
2856		*
2857	<	* <p>The view's <tt>iterator</tt> is a "weakly consistent" iterator
2857	>	* <p>The view's {@code iterator} is a "weakly consistent" iterator
2858		* that will never throw {@link ConcurrentModificationException},
2859		* and guarantees to traverse elements as they existed upon
2860		* construction of the iterator, and may (but is not guaranteed to)
2861		* reflect any modifications subsequent to construction.
2862		*/
2863		public Set<K> keySet() {
2864	<	Set<K> ks = keySet;
2865	<	return (ks != null) ? ks : (keySet = new KeySet());
2864	>	KeySet<K,V> ks = keySet;
2865	>	return (ks != null) ? ks : (keySet = new KeySet<K,V>(this));
2866		}
2867
2868		/**
#	Line 991 | Line 2870 | public class ConcurrentHashMap<K, V> ext
2870		* The collection is backed by the map, so changes to the map are
2871		* reflected in the collection, and vice-versa.  The collection
2872		* supports element removal, which removes the corresponding
2873	<	* mapping from this map, via the <tt>Iterator.remove</tt>,
2874	<	* <tt>Collection.remove</tt>, <tt>removeAll</tt>,
2875	<	* <tt>retainAll</tt>, and <tt>clear</tt> operations.  It does not
2876	<	* support the <tt>add</tt> or <tt>addAll</tt> operations.
2873	>	* mapping from this map, via the {@code Iterator.remove},
2874	>	* {@code Collection.remove}, {@code removeAll},
2875	>	* {@code retainAll}, and {@code clear} operations.  It does not
2876	>	* support the {@code add} or {@code addAll} operations.
2877		*
2878	<	* <p>The view's <tt>iterator</tt> is a "weakly consistent" iterator
2878	>	* <p>The view's {@code iterator} is a "weakly consistent" iterator
2879		* that will never throw {@link ConcurrentModificationException},
2880		* and guarantees to traverse elements as they existed upon
2881		* construction of the iterator, and may (but is not guaranteed to)
2882		* reflect any modifications subsequent to construction.
2883		*/
2884		public Collection<V> values() {
2885	<	Collection<V> vs = values;
2886	<	return (vs != null) ? vs : (values = new Values());
2885	>	Values<K,V> vs = values;
2886	>	return (vs != null) ? vs : (values = new Values<K,V>(this));
2887		}
2888
2889		/**
#	Line 1012 | Line 2891 | public class ConcurrentHashMap<K, V> ext
2891		* The set is backed by the map, so changes to the map are
2892		* reflected in the set, and vice-versa.  The set supports element
2893		* removal, which removes the corresponding mapping from the map,
2894	<	* via the <tt>Iterator.remove</tt>, <tt>Set.remove</tt>,
2895	<	* <tt>removeAll</tt>, <tt>retainAll</tt>, and <tt>clear</tt>
2896	<	* operations.  It does not support the <tt>add</tt> or
2897	<	* <tt>addAll</tt> operations.
2894	>	* via the {@code Iterator.remove}, {@code Set.remove},
2895	>	* {@code removeAll}, {@code retainAll}, and {@code clear}
2896	>	* operations.  It does not support the {@code add} or
2897	>	* {@code addAll} operations.
2898		*
2899	<	* <p>The view's <tt>iterator</tt> is a "weakly consistent" iterator
2899	>	* <p>The view's {@code iterator} is a "weakly consistent" iterator
2900		* that will never throw {@link ConcurrentModificationException},
2901		* and guarantees to traverse elements as they existed upon
2902		* construction of the iterator, and may (but is not guaranteed to)
2903		* reflect any modifications subsequent to construction.
2904		*/
2905		public Set<Map.Entry<K,V>> entrySet() {
2906	<	Set<Map.Entry<K,V>> es = entrySet;
2907	<	return (es != null) ? es : (entrySet = new EntrySet());
2906	>	EntrySet<K,V> es = entrySet;
2907	>	return (es != null) ? es : (entrySet = new EntrySet<K,V>(this));
2908		}
2909
2910		/**
2911		* Returns an enumeration of the keys in this table.
2912		*
2913		* @return an enumeration of the keys in this table
2914	<	* @see #keySet
2914	>	* @see #keySet()
2915		*/
2916		public Enumeration<K> keys() {
2917	<	return new KeyIterator();
2917	>	return new KeyIterator<K,V>(this);
2918		}
2919
2920		/**
2921		* Returns an enumeration of the values in this table.
2922		*
2923		* @return an enumeration of the values in this table
2924	<	* @see #values
2924	>	* @see #values()
2925		*/
2926		public Enumeration<V> elements() {
2927	<	return new ValueIterator();
2927	>	return new ValueIterator<K,V>(this);
2928		}
2929
2930	<	/* ---------------- Iterator Support -------------- */
2931	<
2932	<	abstract class HashIterator {
2933	<	int nextSegmentIndex;
2934	<	int nextTableIndex;
2935	<	HashEntry<K,V>[] currentTable;
2936	<	HashEntry<K, V> nextEntry;
2937	<	HashEntry<K, V> lastReturned;
2930	>	/**
2931	>	* Returns a partitionable iterator of the keys in this map.
2932	>	*
2933	>	* @return a partitionable iterator of the keys in this map
2934	>	*/
2935	>	public Spliterator<K> keySpliterator() {
2936	>	return new KeyIterator<K,V>(this);
2937	>	}
2938
2939	<	HashIterator() {
2940	<	nextSegmentIndex = segments.length - 1;
2941	<	nextTableIndex = -1;
2942	<	advance();
2943	<	}
2939	>	/**
2940	>	* Returns a partitionable iterator of the values in this map.
2941	>	*
2942	>	* @return a partitionable iterator of the values in this map
2943	>	*/
2944	>	public Spliterator<V> valueSpliterator() {
2945	>	return new ValueIterator<K,V>(this);
2946	>	}
2947
2948	<	public boolean hasMoreElements() { return hasNext(); }
2948	>	/**
2949	>	* Returns a partitionable iterator of the entries in this map.
2950	>	*
2951	>	* @return a partitionable iterator of the entries in this map
2952	>	*/
2953	>	public Spliterator<Map.Entry<K,V>> entrySpliterator() {
2954	>	return new EntryIterator<K,V>(this);
2955	>	}
2956
2957	<	final void advance() {
2958	<	if (nextEntry != null && (nextEntry = nextEntry.next) != null)
2959	<	return;
2957	>	/**
2958	>	* Returns the hash code value for this {@link Map}, i.e.,
2959	>	* the sum of, for each key-value pair in the map,
2960	>	* {@code key.hashCode() ^ value.hashCode()}.
2961	>	*
2962	>	* @return the hash code value for this map
2963	>	*/
2964	>	public int hashCode() {
2965	>	int h = 0;
2966	>	Traverser<K,V,Object> it = new Traverser<K,V,Object>(this);
2967	>	Object v;
2968	>	while ((v = it.advance()) != null) {
2969	>	h += it.nextKey.hashCode() ^ v.hashCode();
2970	>	}
2971	>	return h;
2972	>	}
2973
2974	<	while (nextTableIndex >= 0) {
2975	<	if ( (nextEntry = currentTable[nextTableIndex--]) != null)
2976	<	return;
2974	>	/**
2975	>	* Returns a string representation of this map.  The string
2976	>	* representation consists of a list of key-value mappings (in no
2977	>	* particular order) enclosed in braces ("{@code {}}").  Adjacent
2978	>	* mappings are separated by the characters {@code ", "} (comma
2979	>	* and space).  Each key-value mapping is rendered as the key
2980	>	* followed by an equals sign ("{@code =}") followed by the
2981	>	* associated value.
2982	>	*
2983	>	* @return a string representation of this map
2984	>	*/
2985	>	public String toString() {
2986	>	Traverser<K,V,Object> it = new Traverser<K,V,Object>(this);
2987	>	StringBuilder sb = new StringBuilder();
2988	>	sb.append('{');
2989	>	Object v;
2990	>	if ((v = it.advance()) != null) {
2991	>	for (;;) {
2992	>	Object k = it.nextKey;
2993	>	sb.append(k == this ? "(this Map)" : k);
2994	>	sb.append('=');
2995	>	sb.append(v == this ? "(this Map)" : v);
2996	>	if ((v = it.advance()) == null)
2997	>	break;
2998	>	sb.append(',').append(' ');
2999		}
3000	+	}
3001	+	return sb.append('}').toString();
3002	+	}
3003
3004	<	while (nextSegmentIndex >= 0) {
3005	<	Segment<K,V> seg = segments[nextSegmentIndex--];
3006	<	if (seg.count != 0) {
3007	<	currentTable = seg.table;
3008	<	for (int j = currentTable.length - 1; j >= 0; --j) {
3009	<	if ( (nextEntry = currentTable[j]) != null) {
3010	<	nextTableIndex = j - 1;
3011	<	return;
3012	<	}
3013	<	}
3014	<	}
3004	>	/**
3005	>	* Compares the specified object with this map for equality.
3006	>	* Returns {@code true} if the given object is a map with the same
3007	>	* mappings as this map.  This operation may return misleading
3008	>	* results if either map is concurrently modified during execution
3009	>	* of this method.
3010	>	*
3011	>	* @param o object to be compared for equality with this map
3012	>	* @return {@code true} if the specified object is equal to this map
3013	>	*/
3014	>	public boolean equals(Object o) {
3015	>	if (o != this) {
3016	>	if (!(o instanceof Map))
3017	>	return false;
3018	>	Map<?,?> m = (Map<?,?>) o;
3019	>	Traverser<K,V,Object> it = new Traverser<K,V,Object>(this);
3020	>	Object val;
3021	>	while ((val = it.advance()) != null) {
3022	>	Object v = m.get(it.nextKey);
3023	>	if (v == null || (v != val && !v.equals(val)))
3024	>	return false;
3025	>	}
3026	>	for (Map.Entry<?,?> e : m.entrySet()) {
3027	>	Object mk, mv, v;
3028	>	if ((mk = e.getKey()) == null ||
3029	>	(mv = e.getValue()) == null ||
3030	>	(v = internalGet(mk)) == null ||
3031	>	(mv != v && !mv.equals(v)))
3032	>	return false;
3033		}
3034		}
3035	+	return true;
3036	+	}
3037
3038	<	public boolean hasNext() { return nextEntry != null; }
3038	>	/* ----------------Iterators -------------- */
3039
3040	<	HashEntry<K,V> nextEntry() {
3041	<	if (nextEntry == null)
3040	>	@SuppressWarnings("serial") static final class KeyIterator<K,V> extends Traverser<K,V,Object>
3041	>	implements Spliterator<K>, Enumeration<K> {
3042	>	KeyIterator(ConcurrentHashMap<K, V> map) { super(map); }
3043	>	KeyIterator(Traverser<K,V,Object> it) {
3044	>	super(it);
3045	>	}
3046	>	public KeyIterator<K,V> split() {
3047	>	if (last != null || (next != null && nextVal == null))
3048	>	throw new IllegalStateException();
3049	>	return new KeyIterator<K,V>(this);
3050	>	}
3051	>	@SuppressWarnings("unchecked") public final K next() {
3052	>	if (nextVal == null && advance() == null)
3053		throw new NoSuchElementException();
3054	<	lastReturned = nextEntry;
3055	<	advance();
3056	<	return lastReturned;
3054	>	Object k = nextKey;
3055	>	nextVal = null;
3056	>	return (K) k;
3057		}
3058
3059	<	public void remove() {
3060	<	if (lastReturned == null)
3059	>	public final K nextElement() { return next(); }
3060	>	}
3061	>
3062	>	@SuppressWarnings("serial") static final class ValueIterator<K,V> extends Traverser<K,V,Object>
3063	>	implements Spliterator<V>, Enumeration<V> {
3064	>	ValueIterator(ConcurrentHashMap<K, V> map) { super(map); }
3065	>	ValueIterator(Traverser<K,V,Object> it) {
3066	>	super(it);
3067	>	}
3068	>	public ValueIterator<K,V> split() {
3069	>	if (last != null || (next != null && nextVal == null))
3070		throw new IllegalStateException();
3071	<	ConcurrentHashMap.this.remove(lastReturned.key);
1105	<	lastReturned = null;
3071	>	return new ValueIterator<K,V>(this);
3072		}
1107	–	}
3073
3074	<	final class KeyIterator
3075	<	extends HashIterator
3076	<	implements Iterator<K>, Enumeration<K>
3077	<	{
3078	<	public K next()        { return super.nextEntry().key; }
3079	<	public K nextElement() { return super.nextEntry().key; }
3074	>	@SuppressWarnings("unchecked") public final V next() {
3075	>	Object v;
3076	>	if ((v = nextVal) == null && (v = advance()) == null)
3077	>	throw new NoSuchElementException();
3078	>	nextVal = null;
3079	>	return (V) v;
3080	>	}
3081	>
3082	>	public final V nextElement() { return next(); }
3083		}
3084
3085	<	final class ValueIterator
3086	<	extends HashIterator
3087	<	implements Iterator<V>, Enumeration<V>
3088	<	{
3089	<	public V next()        { return super.nextEntry().value; }
3090	<	public V nextElement() { return super.nextEntry().value; }
3085	>	@SuppressWarnings("serial") static final class EntryIterator<K,V> extends Traverser<K,V,Object>
3086	>	implements Spliterator<Map.Entry<K,V>> {
3087	>	EntryIterator(ConcurrentHashMap<K, V> map) { super(map); }
3088	>	EntryIterator(Traverser<K,V,Object> it) {
3089	>	super(it);
3090	>	}
3091	>	public EntryIterator<K,V> split() {
3092	>	if (last != null || (next != null && nextVal == null))
3093	>	throw new IllegalStateException();
3094	>	return new EntryIterator<K,V>(this);
3095	>	}
3096	>
3097	>	@SuppressWarnings("unchecked") public final Map.Entry<K,V> next() {
3098	>	Object v;
3099	>	if ((v = nextVal) == null && (v = advance()) == null)
3100	>	throw new NoSuchElementException();
3101	>	Object k = nextKey;
3102	>	nextVal = null;
3103	>	return new MapEntry<K,V>((K)k, (V)v, map);
3104	>	}
3105		}
3106
3107		/**
3108	<	* Custom Entry class used by EntryIterator.next(), that relays
1127	<	* setValue changes to the underlying map.
3108	>	* Exported Entry for iterators
3109		*/
3110	<	final class WriteThroughEntry
3111	<	extends AbstractMap.SimpleEntry<K,V>
3112	<	{
3113	<	WriteThroughEntry(K k, V v) {
3114	<	super(k,v);
3110	>	static final class MapEntry<K,V> implements Map.Entry<K, V> {
3111	>	final K key; // non-null
3112	>	V val;       // non-null
3113	>	final ConcurrentHashMap<K, V> map;
3114	>	MapEntry(K key, V val, ConcurrentHashMap<K, V> map) {
3115	>	this.key = key;
3116	>	this.val = val;
3117	>	this.map = map;
3118	>	}
3119	>	public final K getKey()       { return key; }
3120	>	public final V getValue()     { return val; }
3121	>	public final int hashCode()   { return key.hashCode() ^ val.hashCode(); }
3122	>	public final String toString(){ return key + "=" + val; }
3123	>
3124	>	public final boolean equals(Object o) {
3125	>	Object k, v; Map.Entry<?,?> e;
3126	>	return ((o instanceof Map.Entry) &&
3127	>	(k = (e = (Map.Entry<?,?>)o).getKey()) != null &&
3128	>	(v = e.getValue()) != null &&
3129	>	(k == key || k.equals(key)) &&
3130	>	(v == val || v.equals(val)));
3131		}
3132
3133		/**
3134	<	* Set our entry's value and write through to the map. The
3135	<	* value to return is somewhat arbitrary here. Since a
3136	<	* WriteThroughEntry does not necessarily track asynchronous
3137	<	* changes, the most recent "previous" value could be
3138	<	* different from what we return (or could even have been
3139	<	* removed in which case the put will re-establish). We do not
1143	<	* and cannot guarantee more.
3134	>	* Sets our entry's value and writes through to the map. The
3135	>	* value to return is somewhat arbitrary here. Since we do not
3136	>	* necessarily track asynchronous changes, the most recent
3137	>	* "previous" value could be different from what we return (or
3138	>	* could even have been removed in which case the put will
3139	>	* re-establish). We do not and cannot guarantee more.
3140		*/
3141	<	public V setValue(V value) {
3141	>	public final V setValue(V value) {
3142		if (value == null) throw new NullPointerException();
3143	<	V v = super.setValue(value);
3144	<	ConcurrentHashMap.this.put(getKey(), value);
3143	>	V v = val;
3144	>	val = value;
3145	>	map.put(key, value);
3146		return v;
3147		}
3148		}
3149
3150	<	final class EntryIterator
1154	<	extends HashIterator
1155	<	implements Iterator<Entry<K,V>>
1156	<	{
1157	<	public Map.Entry<K,V> next() {
1158	<	HashEntry<K,V> e = super.nextEntry();
1159	<	return new WriteThroughEntry(e.key, e.value);
1160	<	}
1161	<	}
3150	>	/* ----------------Views -------------- */
3151
3152	<	final class KeySet extends AbstractSet<K> {
3153	<	public Iterator<K> iterator() {
3154	<	return new KeyIterator();
3155	<	}
3156	<	public int size() {
3157	<	return ConcurrentHashMap.this.size();
3152	>	/**
3153	>	* Base class for views.
3154	>	*/
3155	>	static abstract class CHMView<K, V> {
3156	>	final ConcurrentHashMap<K, V> map;
3157	>	CHMView(ConcurrentHashMap<K, V> map)  { this.map = map; }
3158	>	public final int size()                 { return map.size(); }
3159	>	public final boolean isEmpty()          { return map.isEmpty(); }
3160	>	public final void clear()               { map.clear(); }
3161	>
3162	>	// implementations below rely on concrete classes supplying these
3163	>	abstract public Iterator<?> iterator();
3164	>	abstract public boolean contains(Object o);
3165	>	abstract public boolean remove(Object o);
3166	>
3167	>	private static final String oomeMsg = "Required array size too large";
3168	>
3169	>	public final Object[] toArray() {
3170	>	long sz = map.mappingCount();
3171	>	if (sz > (long)(MAX_ARRAY_SIZE))
3172	>	throw new OutOfMemoryError(oomeMsg);
3173	>	int n = (int)sz;
3174	>	Object[] r = new Object[n];
3175	>	int i = 0;
3176	>	Iterator<?> it = iterator();
3177	>	while (it.hasNext()) {
3178	>	if (i == n) {
3179	>	if (n >= MAX_ARRAY_SIZE)
3180	>	throw new OutOfMemoryError(oomeMsg);
3181	>	if (n >= MAX_ARRAY_SIZE - (MAX_ARRAY_SIZE >>> 1) - 1)
3182	>	n = MAX_ARRAY_SIZE;
3183	>	else
3184	>	n += (n >>> 1) + 1;
3185	>	r = Arrays.copyOf(r, n);
3186	>	}
3187	>	r[i++] = it.next();
3188	>	}
3189	>	return (i == n) ? r : Arrays.copyOf(r, i);
3190		}
3191	<	public boolean contains(Object o) {
3192	<	return ConcurrentHashMap.this.containsKey(o);
3191	>
3192	>	@SuppressWarnings("unchecked") public final <T> T[] toArray(T[] a) {
3193	>	long sz = map.mappingCount();
3194	>	if (sz > (long)(MAX_ARRAY_SIZE))
3195	>	throw new OutOfMemoryError(oomeMsg);
3196	>	int m = (int)sz;
3197	>	T[] r = (a.length >= m) ? a :
3198	>	(T[])java.lang.reflect.Array
3199	>	.newInstance(a.getClass().getComponentType(), m);
3200	>	int n = r.length;
3201	>	int i = 0;
3202	>	Iterator<?> it = iterator();
3203	>	while (it.hasNext()) {
3204	>	if (i == n) {
3205	>	if (n >= MAX_ARRAY_SIZE)
3206	>	throw new OutOfMemoryError(oomeMsg);
3207	>	if (n >= MAX_ARRAY_SIZE - (MAX_ARRAY_SIZE >>> 1) - 1)
3208	>	n = MAX_ARRAY_SIZE;
3209	>	else
3210	>	n += (n >>> 1) + 1;
3211	>	r = Arrays.copyOf(r, n);
3212	>	}
3213	>	r[i++] = (T)it.next();
3214	>	}
3215	>	if (a == r && i < n) {
3216	>	r[i] = null; // null-terminate
3217	>	return r;
3218	>	}
3219	>	return (i == n) ? r : Arrays.copyOf(r, i);
3220		}
3221	<	public boolean remove(Object o) {
3222	<	return ConcurrentHashMap.this.remove(o) != null;
3221	>
3222	>	public final int hashCode() {
3223	>	int h = 0;
3224	>	for (Iterator<?> it = iterator(); it.hasNext();)
3225	>	h += it.next().hashCode();
3226	>	return h;
3227	>	}
3228	>
3229	>	public final String toString() {
3230	>	StringBuilder sb = new StringBuilder();
3231	>	sb.append('[');
3232	>	Iterator<?> it = iterator();
3233	>	if (it.hasNext()) {
3234	>	for (;;) {
3235	>	Object e = it.next();
3236	>	sb.append(e == this ? "(this Collection)" : e);
3237	>	if (!it.hasNext())
3238	>	break;
3239	>	sb.append(',').append(' ');
3240	>	}
3241	>	}
3242	>	return sb.append(']').toString();
3243		}
3244	<	public void clear() {
3245	<	ConcurrentHashMap.this.clear();
3244	>
3245	>	public final boolean containsAll(Collection<?> c) {
3246	>	if (c != this) {
3247	>	for (Iterator<?> it = c.iterator(); it.hasNext();) {
3248	>	Object e = it.next();
3249	>	if (e == null || !contains(e))
3250	>	return false;
3251	>	}
3252	>	}
3253	>	return true;
3254		}
3255	<	public Object[] toArray() {
3256	<	Collection<K> c = new ArrayList<K>(size());
3257	<	for (K k : this)
3258	<	c.add(k);
3259	<	return c.toArray();
3255	>
3256	>	public final boolean removeAll(Collection<?> c) {
3257	>	boolean modified = false;
3258	>	for (Iterator<?> it = iterator(); it.hasNext();) {
3259	>	if (c.contains(it.next())) {
3260	>	it.remove();
3261	>	modified = true;
3262	>	}
3263	>	}
3264	>	return modified;
3265		}
3266	<	public <T> T[] toArray(T[] a) {
3267	<	Collection<K> c = new ArrayList<K>();
3268	<	for (K k : this)
3269	<	c.add(k);
3270	<	return c.toArray(a);
3266	>
3267	>	public final boolean retainAll(Collection<?> c) {
3268	>	boolean modified = false;
3269	>	for (Iterator<?> it = iterator(); it.hasNext();) {
3270	>	if (!c.contains(it.next())) {
3271	>	it.remove();
3272	>	modified = true;
3273	>	}
3274	>	}
3275	>	return modified;
3276		}
3277	+
3278		}
3279
3280	<	final class Values extends AbstractCollection<V> {
3281	<	public Iterator<V> iterator() {
3282	<	return new ValueIterator();
3283	<	}
3284	<	public int size() {
3285	<	return ConcurrentHashMap.this.size();
3286	<	}
3287	<	public boolean contains(Object o) {
3288	<	return ConcurrentHashMap.this.containsValue(o);
3289	<	}
3290	<	public void clear() {
3291	<	ConcurrentHashMap.this.clear();
3292	<	}
3293	<	public Object[] toArray() {
3294	<	Collection<V> c = new ArrayList<V>(size());
3295	<	for (V v : this)
3296	<	c.add(v);
3297	<	return c.toArray();
3298	<	}
3299	<	public <T> T[] toArray(T[] a) {
1213	<	Collection<V> c = new ArrayList<V>(size());
1214	<	for (V v : this)
1215	<	c.add(v);
1216	<	return c.toArray(a);
3280	>	static final class KeySet<K,V> extends CHMView<K,V> implements Set<K> {
3281	>	KeySet(ConcurrentHashMap<K, V> map)  {
3282	>	super(map);
3283	>	}
3284	>	public final boolean contains(Object o) { return map.containsKey(o); }
3285	>	public final boolean remove(Object o)   { return map.remove(o) != null; }
3286	>	public final Iterator<K> iterator() {
3287	>	return new KeyIterator<K,V>(map);
3288	>	}
3289	>	public final boolean add(K e) {
3290	>	throw new UnsupportedOperationException();
3291	>	}
3292	>	public final boolean addAll(Collection<? extends K> c) {
3293	>	throw new UnsupportedOperationException();
3294	>	}
3295	>	public boolean equals(Object o) {
3296	>	Set<?> c;
3297	>	return ((o instanceof Set) &&
3298	>	((c = (Set<?>)o) == this ||
3299	>	(containsAll(c) && c.containsAll(this))));
3300		}
3301		}
3302
3303	<	final class EntrySet extends AbstractSet<Map.Entry<K,V>> {
3304	<	public Iterator<Map.Entry<K,V>> iterator() {
3305	<	return new EntryIterator();
3306	<	}
3307	<	public boolean contains(Object o) {
3308	<	if (!(o instanceof Map.Entry))
3309	<	return false;
3310	<	Map.Entry<?,?> e = (Map.Entry<?,?>)o;
3311	<	V v = ConcurrentHashMap.this.get(e.getKey());
3312	<	return v != null && v.equals(e.getValue());
3313	<	}
3314	<	public boolean remove(Object o) {
3315	<	if (!(o instanceof Map.Entry))
3316	<	return false;
3317	<	Map.Entry<?,?> e = (Map.Entry<?,?>)o;
3318	<	return ConcurrentHashMap.this.remove(e.getKey(), e.getValue());
3303	>
3304	>	static final class Values<K,V> extends CHMView<K,V>
3305	>	implements Collection<V> {
3306	>	Values(ConcurrentHashMap<K, V> map)   { super(map); }
3307	>	public final boolean contains(Object o) { return map.containsValue(o); }
3308	>	public final boolean remove(Object o) {
3309	>	if (o != null) {
3310	>	Iterator<V> it = new ValueIterator<K,V>(map);
3311	>	while (it.hasNext()) {
3312	>	if (o.equals(it.next())) {
3313	>	it.remove();
3314	>	return true;
3315	>	}
3316	>	}
3317	>	}
3318	>	return false;
3319		}
3320	<	public int size() {
3321	<	return ConcurrentHashMap.this.size();
3320	>	public final Iterator<V> iterator() {
3321	>	return new ValueIterator<K,V>(map);
3322		}
3323	<	public void clear() {
3324	<	ConcurrentHashMap.this.clear();
3323	>	public final boolean add(V e) {
3324	>	throw new UnsupportedOperationException();
3325		}
3326	<	public Object[] toArray() {
3327	<	Collection<Map.Entry<K,V>> c = new ArrayList<Map.Entry<K,V>>(size());
1245	<	for (Map.Entry<K,V> e : this)
1246	<	c.add(e);
1247	<	return c.toArray();
1248	<	}
1249	<	public <T> T[] toArray(T[] a) {
1250	<	Collection<Map.Entry<K,V>> c = new ArrayList<Map.Entry<K,V>>(size());
1251	<	for (Map.Entry<K,V> e : this)
1252	<	c.add(e);
1253	<	return c.toArray(a);
3326	>	public final boolean addAll(Collection<? extends V> c) {
3327	>	throw new UnsupportedOperationException();
3328		}
3329
3330		}
3331
3332	+	static final class EntrySet<K,V> extends CHMView<K,V>
3333	+	implements Set<Map.Entry<K,V>> {
3334	+	EntrySet(ConcurrentHashMap<K, V> map) { super(map); }
3335	+	public final boolean contains(Object o) {
3336	+	Object k, v, r; Map.Entry<?,?> e;
3337	+	return ((o instanceof Map.Entry) &&
3338	+	(k = (e = (Map.Entry<?,?>)o).getKey()) != null &&
3339	+	(r = map.get(k)) != null &&
3340	+	(v = e.getValue()) != null &&
3341	+	(v == r || v.equals(r)));
3342	+	}
3343	+	public final boolean remove(Object o) {
3344	+	Object k, v; Map.Entry<?,?> e;
3345	+	return ((o instanceof Map.Entry) &&
3346	+	(k = (e = (Map.Entry<?,?>)o).getKey()) != null &&
3347	+	(v = e.getValue()) != null &&
3348	+	map.remove(k, v));
3349	+	}
3350	+	public final Iterator<Map.Entry<K,V>> iterator() {
3351	+	return new EntryIterator<K,V>(map);
3352	+	}
3353	+	public final boolean add(Entry<K,V> e) {
3354	+	throw new UnsupportedOperationException();
3355	+	}
3356	+	public final boolean addAll(Collection<? extends Entry<K,V>> c) {
3357	+	throw new UnsupportedOperationException();
3358	+	}
3359	+	public boolean equals(Object o) {
3360	+	Set<?> c;
3361	+	return ((o instanceof Set) &&
3362	+	((c = (Set<?>)o) == this ||
3363	+	(containsAll(c) && c.containsAll(this))));
3364	+	}
3365	+	}
3366	+
3367		/* ---------------- Serialization Support -------------- */
3368
3369		/**
3370	<	* Save the state of the <tt>ConcurrentHashMap</tt> instance to a
3371	<	* stream (i.e., serialize it).
3370	>	* Stripped-down version of helper class used in previous version,
3371	>	* declared for the sake of serialization compatibility
3372	>	*/
3373	>	static class Segment<K,V> implements Serializable {
3374	>	private static final long serialVersionUID = 2249069246763182397L;
3375	>	final float loadFactor;
3376	>	Segment(float lf) { this.loadFactor = lf; }
3377	>	}
3378	>
3379	>	/**
3380	>	* Saves the state of the {@code ConcurrentHashMap} instance to a
3381	>	* stream (i.e., serializes it).
3382		* @param s the stream
3383		* @serialData
3384		* the key (Object) and value (Object)
3385		* for each key-value mapping, followed by a null pair.
3386		* The key-value mappings are emitted in no particular order.
3387		*/
3388	<	private void writeObject(java.io.ObjectOutputStream s) throws IOException  {
3388	>	@SuppressWarnings("unchecked") private void writeObject(java.io.ObjectOutputStream s)
3389	>	throws java.io.IOException {
3390	>	if (segments == null) { // for serialization compatibility
3391	>	segments = (Segment<K,V>[])
3392	>	new Segment<?,?>[DEFAULT_CONCURRENCY_LEVEL];
3393	>	for (int i = 0; i < segments.length; ++i)
3394	>	segments[i] = new Segment<K,V>(LOAD_FACTOR);
3395	>	}
3396		s.defaultWriteObject();
3397	<
3398	<	for (int k = 0; k < segments.length; ++k) {
3399	<	Segment<K,V> seg = segments[k];
3400	<	seg.lock();
3401	<	try {
1276	<	HashEntry<K,V>[] tab = seg.table;
1277	<	for (int i = 0; i < tab.length; ++i) {
1278	<	for (HashEntry<K,V> e = tab[i]; e != null; e = e.next) {
1279	<	s.writeObject(e.key);
1280	<	s.writeObject(e.value);
1281	<	}
1282	<	}
1283	<	} finally {
1284	<	seg.unlock();
1285	<	}
3397	>	Traverser<K,V,Object> it = new Traverser<K,V,Object>(this);
3398	>	Object v;
3399	>	while ((v = it.advance()) != null) {
3400	>	s.writeObject(it.nextKey);
3401	>	s.writeObject(v);
3402		}
3403		s.writeObject(null);
3404		s.writeObject(null);
3405	+	segments = null; // throw away
3406		}
3407
3408		/**
3409	<	* Reconstitute the <tt>ConcurrentHashMap</tt> instance from a
1293	<	* stream (i.e., deserialize it).
3409	>	* Reconstitutes the instance from a stream (that is, deserializes it).
3410		* @param s the stream
3411		*/
3412	<	private void readObject(java.io.ObjectInputStream s)
3413	<	throws IOException, ClassNotFoundException  {
3412	>	@SuppressWarnings("unchecked") private void readObject(java.io.ObjectInputStream s)
3413	>	throws java.io.IOException, ClassNotFoundException {
3414		s.defaultReadObject();
3415	+	this.segments = null; // unneeded
3416	+	// initialize transient final field
3417	+	UNSAFE.putObjectVolatile(this, counterOffset, new LongAdder());
3418	+
3419	+	// Create all nodes, then place in table once size is known
3420	+	long size = 0L;
3421	+	Node p = null;
3422	+	for (;;) {
3423	+	K k = (K) s.readObject();
3424	+	V v = (V) s.readObject();
3425	+	if (k != null && v != null) {
3426	+	int h = spread(k.hashCode());
3427	+	p = new Node(h, k, v, p);
3428	+	++size;
3429	+	}
3430	+	else
3431	+	break;
3432	+	}
3433	+	if (p != null) {
3434	+	boolean init = false;
3435	+	int n;
3436	+	if (size >= (long)(MAXIMUM_CAPACITY >>> 1))
3437	+	n = MAXIMUM_CAPACITY;
3438	+	else {
3439	+	int sz = (int)size;
3440	+	n = tableSizeFor(sz + (sz >>> 1) + 1);
3441	+	}
3442	+	int sc = sizeCtl;
3443	+	boolean collide = false;
3444	+	if (n > sc &&
3445	+	UNSAFE.compareAndSwapInt(this, sizeCtlOffset, sc, -1)) {
3446	+	try {
3447	+	if (table == null) {
3448	+	init = true;
3449	+	Node[] tab = new Node[n];
3450	+	int mask = n - 1;
3451	+	while (p != null) {
3452	+	int j = p.hash & mask;
3453	+	Node next = p.next;
3454	+	Node q = p.next = tabAt(tab, j);
3455	+	setTabAt(tab, j, p);
3456	+	if (!collide && q != null && q.hash == p.hash)
3457	+	collide = true;
3458	+	p = next;
3459	+	}
3460	+	table = tab;
3461	+	counter.add(size);
3462	+	sc = n - (n >>> 2);
3463	+	}
3464	+	} finally {
3465	+	sizeCtl = sc;
3466	+	}
3467	+	if (collide) { // rescan and convert to TreeBins
3468	+	Node[] tab = table;
3469	+	for (int i = 0; i < tab.length; ++i) {
3470	+	int c = 0;
3471	+	for (Node e = tabAt(tab, i); e != null; e = e.next) {
3472	+	if (++c > TREE_THRESHOLD &&
3473	+	(e.key instanceof Comparable)) {
3474	+	replaceWithTreeBin(tab, i, e.key);
3475	+	break;
3476	+	}
3477	+	}
3478	+	}
3479	+	}
3480	+	}
3481	+	if (!init) { // Can only happen if unsafely published.
3482	+	while (p != null) {
3483	+	internalPut(p.key, p.val);
3484	+	p = p.next;
3485	+	}
3486	+	}
3487	+	}
3488	+	}
3489	+
3490	+
3491	+	// -------------------------------------------------------
3492	+
3493	+	// Sams
3494	+	/** Interface describing a void action of one argument */
3495	+	public interface Action<A> { void apply(A a); }
3496	+	/** Interface describing a void action of two arguments */
3497	+	public interface BiAction<A,B> { void apply(A a, B b); }
3498	+	/** Interface describing a function of one argument */
3499	+	public interface Fun<A,T> { T apply(A a); }
3500	+	/** Interface describing a function of two arguments */
3501	+	public interface BiFun<A,B,T> { T apply(A a, B b); }
3502	+	/** Interface describing a function of no arguments */
3503	+	public interface Generator<T> { T apply(); }
3504	+	/** Interface describing a function mapping its argument to a double */
3505	+	public interface ObjectToDouble<A> { double apply(A a); }
3506	+	/** Interface describing a function mapping its argument to a long */
3507	+	public interface ObjectToLong<A> { long apply(A a); }
3508	+	/** Interface describing a function mapping its argument to an int */
3509	+	public interface ObjectToInt<A> {int apply(A a); }
3510	+	/** Interface describing a function mapping two arguments to a double */
3511	+	public interface ObjectByObjectToDouble<A,B> { double apply(A a, B b); }
3512	+	/** Interface describing a function mapping two arguments to a long */
3513	+	public interface ObjectByObjectToLong<A,B> { long apply(A a, B b); }
3514	+	/** Interface describing a function mapping two arguments to an int */
3515	+	public interface ObjectByObjectToInt<A,B> {int apply(A a, B b); }
3516	+	/** Interface describing a function mapping a double to a double */
3517	+	public interface DoubleToDouble { double apply(double a); }
3518	+	/** Interface describing a function mapping a long to a long */
3519	+	public interface LongToLong { long apply(long a); }
3520	+	/** Interface describing a function mapping an int to an int */
3521	+	public interface IntToInt { int apply(int a); }
3522	+	/** Interface describing a function mapping two doubles to a double */
3523	+	public interface DoubleByDoubleToDouble { double apply(double a, double b); }
3524	+	/** Interface describing a function mapping two longs to a long */
3525	+	public interface LongByLongToLong { long apply(long a, long b); }
3526	+	/** Interface describing a function mapping two ints to an int */
3527	+	public interface IntByIntToInt { int apply(int a, int b); }
3528	+
3529	+
3530	+	// -------------------------------------------------------
3531	+
3532	+	/**
3533	+	* Returns an extended {@link Parallel} view of this map using the
3534	+	* given executor for bulk parallel operations.
3535	+	*
3536	+	* @param executor the executor
3537	+	* @return a parallel view
3538	+	*/
3539	+	public Parallel parallel(ForkJoinPool executor)  {
3540	+	return new Parallel(executor);
3541	+	}
3542
3543	<	// Initialize each segment to be minimally sized, and let grow.
3544	<	for (int i = 0; i < segments.length; ++i) {
3545	<	segments[i].setTable(new HashEntry[1]);
3543	>	/**
3544	>	* An extended view of a ConcurrentHashMap supporting bulk
3545	>	* parallel operations. These operations are designed to be
3546	>	* safely, and often sensibly, applied even with maps that are
3547	>	* being concurrently updated by other threads; for example, when
3548	>	* computing a snapshot summary of the values in a shared
3549	>	* registry.  There are three kinds of operation, each with four
3550	>	* forms, accepting functions with Keys, Values, Entries, and
3551	>	* (Key, Value) arguments and/or return values. Because the
3552	>	* elements of a ConcurrentHashMap are not ordered in any
3553	>	* particular way, and may be processed in different orders in
3554	>	* different parallel executions, the correctness of supplied
3555	>	* functions should not depend on any ordering, or on any other
3556	>	* objects or values that may transiently change while computation
3557	>	* is in progress; and except for forEach actions, should ideally
3558	>	* be side-effect-free.
3559	>	*
3560	>	* <ul>
3561	>	* <li> forEach: Perform a given action on each element.
3562	>	* A variant form applies a given transformation on each element
3563	>	* before performing the action.</li>
3564	>	*
3565	>	* <li> search: Return the first available non-null result of
3566	>	* applying a given function on each element; skipping further
3567	>	* search when a result is found.</li>
3568	>	*
3569	>	* <li> reduce: Accumulate each element.  The supplied reduction
3570	>	* function cannot rely on ordering (more formally, it should be
3571	>	* both associative and commutative).  There are five variants:
3572	>	*
3573	>	* <ul>
3574	>	*
3575	>	* <li> Plain reductions. (There is not a form of this method for
3576	>	* (key, value) function arguments since there is no corresponding
3577	>	* return type.)</li>
3578	>	*
3579	>	* <li> Mapped reductions that accumulate the results of a given
3580	>	* function applied to each element.</li>
3581	>	*
3582	>	* <li> Reductions to scalar doubles, longs, and ints, using a
3583	>	* given basis value.</li>
3584	>	*
3585	>	* </li>
3586	>	* </ul>
3587	>	* </ul>
3588	>	*
3589	>	* <p>The concurrency properties of the bulk operations follow
3590	>	* from those of ConcurrentHashMap: Any non-null result returned
3591	>	* from {@code get(key)} and related access methods bears a
3592	>	* happens-before relation with the associated insertion or
3593	>	* update.  The result of any bulk operation reflects the
3594	>	* composition of these per-element relations (but is not
3595	>	* necessarily atomic with respect to the map as a whole unless it
3596	>	* is somehow known to be quiescent).  Conversely, because keys
3597	>	* and values in the map are never null, null serves as a reliable
3598	>	* atomic indicator of the current lack of any result.  To
3599	>	* maintain this property, null serves as an implicit basis for
3600	>	* all non-scalar reduction operations. For the double, long, and
3601	>	* int versions, the basis should be one that, when combined with
3602	>	* any other value, returns that other value (more formally, it
3603	>	* should be the identity element for the reduction). Most common
3604	>	* reductions have these properties; for example, computing a sum
3605	>	* with basis 0 or a minimum with basis MAX_VALUE.
3606	>	*
3607	>	* <p>Search and transformation functions provided as arguments
3608	>	* should similarly return null to indicate the lack of any result
3609	>	* (in which case it is not used). In the case of mapped
3610	>	* reductions, this also enables transformations to serve as
3611	>	* filters, returning null (or, in the case of primitive
3612	>	* specializations, the identity basis) if the element should not
3613	>	* be combined. You can create compound transformations and
3614	>	* filterings by composing them yourself under this "null means
3615	>	* there is nothing there now" rule before using them in search or
3616	>	* reduce operations.
3617	>	*
3618	>	* <p>Methods accepting and/or returning Entry arguments maintain
3619	>	* key-value associations. They may be useful for example when
3620	>	* finding the key for the greatest value. Note that "plain" Entry
3621	>	* arguments can be supplied using {@code new
3622	>	* AbstractMap.SimpleEntry(k,v)}.
3623	>	*
3624	>	* <p> Bulk operations may complete abruptly, throwing an
3625	>	* exception encountered in the application of a supplied
3626	>	* function. Bear in mind when handling such exceptions that other
3627	>	* concurrently executing functions could also have thrown
3628	>	* exceptions, or would have done so if the first exception had
3629	>	* not occurred.
3630	>	*
3631	>	* <p>Parallel speedups compared to sequential processing are
3632	>	* common but not guaranteed.  Operations involving brief
3633	>	* functions on small maps may execute more slowly than sequential
3634	>	* loops if the underlying work to parallelize the computation is
3635	>	* more expensive than the computation itself. Similarly,
3636	>	* parallelization may not lead to much actual parallelism if all
3637	>	* processors are busy performing unrelated tasks.
3638	>	*
3639	>	* <p> All arguments to all task methods must be non-null.
3640	>	*
3641	>	* <p><em>jsr166e note: During transition, this class
3642	>	* uses nested functional interfaces with different names but the
3643	>	* same forms as those expected for JDK8.<em>
3644	>	*/
3645	>	public class Parallel {
3646	>	final ForkJoinPool fjp;
3647	>
3648	>	/**
3649	>	* Returns an extended view of this map using the given
3650	>	* executor for bulk parallel operations.
3651	>	*
3652	>	* @param executor the executor
3653	>	*/
3654	>	public Parallel(ForkJoinPool executor)  {
3655	>	this.fjp = executor;
3656		}
3657
3658	<	// Read the keys and values, and put the mappings in the table
3659	<	for (;;) {
3660	<	K key = (K) s.readObject();
3661	<	V value = (V) s.readObject();
3662	<	if (key == null)
3663	<	break;
3664	<	put(key, value);
3658	>	/**
3659	>	* Performs the given action for each (key, value).
3660	>	*
3661	>	* @param action the action
3662	>	*/
3663	>	public void forEach(BiAction<K,V> action) {
3664	>	fjp.invoke(ForkJoinTasks.forEach
3665	>	(ConcurrentHashMap.this, action));
3666	>	}
3667	>
3668	>	/**
3669	>	* Performs the given action for each non-null transformation
3670	>	* of each (key, value).
3671	>	*
3672	>	* @param transformer a function returning the transformation
3673	>	* for an element, or null of there is no transformation (in
3674	>	* which case the action is not applied)
3675	>	* @param action the action
3676	>	*/
3677	>	public <U> void forEach(BiFun<? super K, ? super V, ? extends U> transformer,
3678	>	Action<U> action) {
3679	>	fjp.invoke(ForkJoinTasks.forEach
3680	>	(ConcurrentHashMap.this, transformer, action));
3681	>	}
3682	>
3683	>	/**
3684	>	* Returns a non-null result from applying the given search
3685	>	* function on each (key, value), or null if none.  Upon
3686	>	* success, further element processing is suppressed and the
3687	>	* results of any other parallel invocations of the search
3688	>	* function are ignored.
3689	>	*
3690	>	* @param searchFunction a function returning a non-null
3691	>	* result on success, else null
3692	>	* @return a non-null result from applying the given search
3693	>	* function on each (key, value), or null if none
3694	>	*/
3695	>	public <U> U search(BiFun<? super K, ? super V, ? extends U> searchFunction) {
3696	>	return fjp.invoke(ForkJoinTasks.search
3697	>	(ConcurrentHashMap.this, searchFunction));
3698	>	}
3699	>
3700	>	/**
3701	>	* Returns the result of accumulating the given transformation
3702	>	* of all (key, value) pairs using the given reducer to
3703	>	* combine values, or null if none.
3704	>	*
3705	>	* @param transformer a function returning the transformation
3706	>	* for an element, or null of there is no transformation (in
3707	>	* which case it is not combined)
3708	>	* @param reducer a commutative associative combining function
3709	>	* @return the result of accumulating the given transformation
3710	>	* of all (key, value) pairs
3711	>	*/
3712	>	public <U> U reduce(BiFun<? super K, ? super V, ? extends U> transformer,
3713	>	BiFun<? super U, ? super U, ? extends U> reducer) {
3714	>	return fjp.invoke(ForkJoinTasks.reduce
3715	>	(ConcurrentHashMap.this, transformer, reducer));
3716	>	}
3717	>
3718	>	/**
3719	>	* Returns the result of accumulating the given transformation
3720	>	* of all (key, value) pairs using the given reducer to
3721	>	* combine values, and the given basis as an identity value.
3722	>	*
3723	>	* @param transformer a function returning the transformation
3724	>	* for an element
3725	>	* @param basis the identity (initial default value) for the reduction
3726	>	* @param reducer a commutative associative combining function
3727	>	* @return the result of accumulating the given transformation
3728	>	* of all (key, value) pairs
3729	>	*/
3730	>	public double reduceToDouble(ObjectByObjectToDouble<? super K, ? super V> transformer,
3731	>	double basis,
3732	>	DoubleByDoubleToDouble reducer) {
3733	>	return fjp.invoke(ForkJoinTasks.reduceToDouble
3734	>	(ConcurrentHashMap.this, transformer, basis, reducer));
3735	>	}
3736	>
3737	>	/**
3738	>	* Returns the result of accumulating the given transformation
3739	>	* of all (key, value) pairs using the given reducer to
3740	>	* combine values, and the given basis as an identity value.
3741	>	*
3742	>	* @param transformer a function returning the transformation
3743	>	* for an element
3744	>	* @param basis the identity (initial default value) for the reduction
3745	>	* @param reducer a commutative associative combining function
3746	>	* @return the result of accumulating the given transformation
3747	>	* of all (key, value) pairs
3748	>	*/
3749	>	public long reduceToLong(ObjectByObjectToLong<? super K, ? super V> transformer,
3750	>	long basis,
3751	>	LongByLongToLong reducer) {
3752	>	return fjp.invoke(ForkJoinTasks.reduceToLong
3753	>	(ConcurrentHashMap.this, transformer, basis, reducer));
3754	>	}
3755	>
3756	>	/**
3757	>	* Returns the result of accumulating the given transformation
3758	>	* of all (key, value) pairs using the given reducer to
3759	>	* combine values, and the given basis as an identity value.
3760	>	*
3761	>	* @param transformer a function returning the transformation
3762	>	* for an element
3763	>	* @param basis the identity (initial default value) for the reduction
3764	>	* @param reducer a commutative associative combining function
3765	>	* @return the result of accumulating the given transformation
3766	>	* of all (key, value) pairs
3767	>	*/
3768	>	public int reduceToInt(ObjectByObjectToInt<? super K, ? super V> transformer,
3769	>	int basis,
3770	>	IntByIntToInt reducer) {
3771	>	return fjp.invoke(ForkJoinTasks.reduceToInt
3772	>	(ConcurrentHashMap.this, transformer, basis, reducer));
3773	>	}
3774	>
3775	>	/**
3776	>	* Performs the given action for each key.
3777	>	*
3778	>	* @param action the action
3779	>	*/
3780	>	public void forEachKey(Action<K> action) {
3781	>	fjp.invoke(ForkJoinTasks.forEachKey
3782	>	(ConcurrentHashMap.this, action));
3783	>	}
3784	>
3785	>	/**
3786	>	* Performs the given action for each non-null transformation
3787	>	* of each key.
3788	>	*
3789	>	* @param transformer a function returning the transformation
3790	>	* for an element, or null of there is no transformation (in
3791	>	* which case the action is not applied)
3792	>	* @param action the action
3793	>	*/
3794	>	public <U> void forEachKey(Fun<? super K, ? extends U> transformer,
3795	>	Action<U> action) {
3796	>	fjp.invoke(ForkJoinTasks.forEachKey
3797	>	(ConcurrentHashMap.this, transformer, action));
3798	>	}
3799	>
3800	>	/**
3801	>	* Returns a non-null result from applying the given search
3802	>	* function on each key, or null if none. Upon success,
3803	>	* further element processing is suppressed and the results of
3804	>	* any other parallel invocations of the search function are
3805	>	* ignored.
3806	>	*
3807	>	* @param searchFunction a function returning a non-null
3808	>	* result on success, else null
3809	>	* @return a non-null result from applying the given search
3810	>	* function on each key, or null if none
3811	>	*/
3812	>	public <U> U searchKeys(Fun<? super K, ? extends U> searchFunction) {
3813	>	return fjp.invoke(ForkJoinTasks.searchKeys
3814	>	(ConcurrentHashMap.this, searchFunction));
3815	>	}
3816	>
3817	>	/**
3818	>	* Returns the result of accumulating all keys using the given
3819	>	* reducer to combine values, or null if none.
3820	>	*
3821	>	* @param reducer a commutative associative combining function
3822	>	* @return the result of accumulating all keys using the given
3823	>	* reducer to combine values, or null if none
3824	>	*/
3825	>	public K reduceKeys(BiFun<? super K, ? super K, ? extends K> reducer) {
3826	>	return fjp.invoke(ForkJoinTasks.reduceKeys
3827	>	(ConcurrentHashMap.this, reducer));
3828	>	}
3829	>
3830	>	/**
3831	>	* Returns the result of accumulating the given transformation
3832	>	* of all keys using the given reducer to combine values, or
3833	>	* null if none.
3834	>	*
3835	>	* @param transformer a function returning the transformation
3836	>	* for an element, or null of there is no transformation (in
3837	>	* which case it is not combined)
3838	>	* @param reducer a commutative associative combining function
3839	>	* @return the result of accumulating the given transformation
3840	>	* of all keys
3841	>	*/
3842	>	public <U> U reduceKeys(Fun<? super K, ? extends U> transformer,
3843	>	BiFun<? super U, ? super U, ? extends U> reducer) {
3844	>	return fjp.invoke(ForkJoinTasks.reduceKeys
3845	>	(ConcurrentHashMap.this, transformer, reducer));
3846	>	}
3847	>
3848	>	/**
3849	>	* Returns the result of accumulating the given transformation
3850	>	* of all keys using the given reducer to combine values, and
3851	>	* the given basis as an identity value.
3852	>	*
3853	>	* @param transformer a function returning the transformation
3854	>	* for an element
3855	>	* @param basis the identity (initial default value) for the reduction
3856	>	* @param reducer a commutative associative combining function
3857	>	* @return  the result of accumulating the given transformation
3858	>	* of all keys
3859	>	*/
3860	>	public double reduceKeysToDouble(ObjectToDouble<? super K> transformer,
3861	>	double basis,
3862	>	DoubleByDoubleToDouble reducer) {
3863	>	return fjp.invoke(ForkJoinTasks.reduceKeysToDouble
3864	>	(ConcurrentHashMap.this, transformer, basis, reducer));
3865	>	}
3866	>
3867	>	/**
3868	>	* Returns the result of accumulating the given transformation
3869	>	* of all keys using the given reducer to combine values, and
3870	>	* the given basis as an identity value.
3871	>	*
3872	>	* @param transformer a function returning the transformation
3873	>	* for an element
3874	>	* @param basis the identity (initial default value) for the reduction
3875	>	* @param reducer a commutative associative combining function
3876	>	* @return the result of accumulating the given transformation
3877	>	* of all keys
3878	>	*/
3879	>	public long reduceKeysToLong(ObjectToLong<? super K> transformer,
3880	>	long basis,
3881	>	LongByLongToLong reducer) {
3882	>	return fjp.invoke(ForkJoinTasks.reduceKeysToLong
3883	>	(ConcurrentHashMap.this, transformer, basis, reducer));
3884	>	}
3885	>
3886	>	/**
3887	>	* Returns the result of accumulating the given transformation
3888	>	* of all keys using the given reducer to combine values, and
3889	>	* the given basis as an identity value.
3890	>	*
3891	>	* @param transformer a function returning the transformation
3892	>	* for an element
3893	>	* @param basis the identity (initial default value) for the reduction
3894	>	* @param reducer a commutative associative combining function
3895	>	* @return the result of accumulating the given transformation
3896	>	* of all keys
3897	>	*/
3898	>	public int reduceKeysToInt(ObjectToInt<? super K> transformer,
3899	>	int basis,
3900	>	IntByIntToInt reducer) {
3901	>	return fjp.invoke(ForkJoinTasks.reduceKeysToInt
3902	>	(ConcurrentHashMap.this, transformer, basis, reducer));
3903	>	}
3904	>
3905	>	/**
3906	>	* Performs the given action for each value.
3907	>	*
3908	>	* @param action the action
3909	>	*/
3910	>	public void forEachValue(Action<V> action) {
3911	>	fjp.invoke(ForkJoinTasks.forEachValue
3912	>	(ConcurrentHashMap.this, action));
3913	>	}
3914	>
3915	>	/**
3916	>	* Performs the given action for each non-null transformation
3917	>	* of each value.
3918	>	*
3919	>	* @param transformer a function returning the transformation
3920	>	* for an element, or null of there is no transformation (in
3921	>	* which case the action is not applied)
3922	>	*/
3923	>	public <U> void forEachValue(Fun<? super V, ? extends U> transformer,
3924	>	Action<U> action) {
3925	>	fjp.invoke(ForkJoinTasks.forEachValue
3926	>	(ConcurrentHashMap.this, transformer, action));
3927	>	}
3928	>
3929	>	/**
3930	>	* Returns a non-null result from applying the given search
3931	>	* function on each value, or null if none.  Upon success,
3932	>	* further element processing is suppressed and the results of
3933	>	* any other parallel invocations of the search function are
3934	>	* ignored.
3935	>	*
3936	>	* @param searchFunction a function returning a non-null
3937	>	* result on success, else null
3938	>	* @return a non-null result from applying the given search
3939	>	* function on each value, or null if none
3940	>	*
3941	>	*/
3942	>	public <U> U searchValues(Fun<? super V, ? extends U> searchFunction) {
3943	>	return fjp.invoke(ForkJoinTasks.searchValues
3944	>	(ConcurrentHashMap.this, searchFunction));
3945	>	}
3946	>
3947	>	/**
3948	>	* Returns the result of accumulating all values using the
3949	>	* given reducer to combine values, or null if none.
3950	>	*
3951	>	* @param reducer a commutative associative combining function
3952	>	* @return  the result of accumulating all values
3953	>	*/
3954	>	public V reduceValues(BiFun<? super V, ? super V, ? extends V> reducer) {
3955	>	return fjp.invoke(ForkJoinTasks.reduceValues
3956	>	(ConcurrentHashMap.this, reducer));
3957	>	}
3958	>
3959	>	/**
3960	>	* Returns the result of accumulating the given transformation
3961	>	* of all values using the given reducer to combine values, or
3962	>	* null if none.
3963	>	*
3964	>	* @param transformer a function returning the transformation
3965	>	* for an element, or null of there is no transformation (in
3966	>	* which case it is not combined)
3967	>	* @param reducer a commutative associative combining function
3968	>	* @return the result of accumulating the given transformation
3969	>	* of all values
3970	>	*/
3971	>	public <U> U reduceValues(Fun<? super V, ? extends U> transformer,
3972	>	BiFun<? super U, ? super U, ? extends U> reducer) {
3973	>	return fjp.invoke(ForkJoinTasks.reduceValues
3974	>	(ConcurrentHashMap.this, transformer, reducer));
3975	>	}
3976	>
3977	>	/**
3978	>	* Returns the result of accumulating the given transformation
3979	>	* of all values using the given reducer to combine values,
3980	>	* and the given basis as an identity value.
3981	>	*
3982	>	* @param transformer a function returning the transformation
3983	>	* for an element
3984	>	* @param basis the identity (initial default value) for the reduction
3985	>	* @param reducer a commutative associative combining function
3986	>	* @return the result of accumulating the given transformation
3987	>	* of all values
3988	>	*/
3989	>	public double reduceValuesToDouble(ObjectToDouble<? super V> transformer,
3990	>	double basis,
3991	>	DoubleByDoubleToDouble reducer) {
3992	>	return fjp.invoke(ForkJoinTasks.reduceValuesToDouble
3993	>	(ConcurrentHashMap.this, transformer, basis, reducer));
3994	>	}
3995	>
3996	>	/**
3997	>	* Returns the result of accumulating the given transformation
3998	>	* of all values using the given reducer to combine values,
3999	>	* and the given basis as an identity value.
4000	>	*
4001	>	* @param transformer a function returning the transformation
4002	>	* for an element
4003	>	* @param basis the identity (initial default value) for the reduction
4004	>	* @param reducer a commutative associative combining function
4005	>	* @return the result of accumulating the given transformation
4006	>	* of all values
4007	>	*/
4008	>	public long reduceValuesToLong(ObjectToLong<? super V> transformer,
4009	>	long basis,
4010	>	LongByLongToLong reducer) {
4011	>	return fjp.invoke(ForkJoinTasks.reduceValuesToLong
4012	>	(ConcurrentHashMap.this, transformer, basis, reducer));
4013	>	}
4014	>
4015	>	/**
4016	>	* Returns the result of accumulating the given transformation
4017	>	* of all values using the given reducer to combine values,
4018	>	* and the given basis as an identity value.
4019	>	*
4020	>	* @param transformer a function returning the transformation
4021	>	* for an element
4022	>	* @param basis the identity (initial default value) for the reduction
4023	>	* @param reducer a commutative associative combining function
4024	>	* @return the result of accumulating the given transformation
4025	>	* of all values
4026	>	*/
4027	>	public int reduceValuesToInt(ObjectToInt<? super V> transformer,
4028	>	int basis,
4029	>	IntByIntToInt reducer) {
4030	>	return fjp.invoke(ForkJoinTasks.reduceValuesToInt
4031	>	(ConcurrentHashMap.this, transformer, basis, reducer));
4032	>	}
4033	>
4034	>	/**
4035	>	* Performs the given action for each entry.
4036	>	*
4037	>	* @param action the action
4038	>	*/
4039	>	public void forEachEntry(Action<Map.Entry<K,V>> action) {
4040	>	fjp.invoke(ForkJoinTasks.forEachEntry
4041	>	(ConcurrentHashMap.this, action));
4042	>	}
4043	>
4044	>	/**
4045	>	* Performs the given action for each non-null transformation
4046	>	* of each entry.
4047	>	*
4048	>	* @param transformer a function returning the transformation
4049	>	* for an element, or null of there is no transformation (in
4050	>	* which case the action is not applied)
4051	>	* @param action the action
4052	>	*/
4053	>	public <U> void forEachEntry(Fun<Map.Entry<K,V>, ? extends U> transformer,
4054	>	Action<U> action) {
4055	>	fjp.invoke(ForkJoinTasks.forEachEntry
4056	>	(ConcurrentHashMap.this, transformer, action));
4057	>	}
4058	>
4059	>	/**
4060	>	* Returns a non-null result from applying the given search
4061	>	* function on each entry, or null if none.  Upon success,
4062	>	* further element processing is suppressed and the results of
4063	>	* any other parallel invocations of the search function are
4064	>	* ignored.
4065	>	*
4066	>	* @param searchFunction a function returning a non-null
4067	>	* result on success, else null
4068	>	* @return a non-null result from applying the given search
4069	>	* function on each entry, or null if none
4070	>	*/
4071	>	public <U> U searchEntries(Fun<Map.Entry<K,V>, ? extends U> searchFunction) {
4072	>	return fjp.invoke(ForkJoinTasks.searchEntries
4073	>	(ConcurrentHashMap.this, searchFunction));
4074	>	}
4075	>
4076	>	/**
4077	>	* Returns the result of accumulating all entries using the
4078	>	* given reducer to combine values, or null if none.
4079	>	*
4080	>	* @param reducer a commutative associative combining function
4081	>	* @return the result of accumulating all entries
4082	>	*/
4083	>	public Map.Entry<K,V> reduceEntries(BiFun<Map.Entry<K,V>, Map.Entry<K,V>, ? extends Map.Entry<K,V>> reducer) {
4084	>	return fjp.invoke(ForkJoinTasks.reduceEntries
4085	>	(ConcurrentHashMap.this, reducer));
4086	>	}
4087	>
4088	>	/**
4089	>	* Returns the result of accumulating the given transformation
4090	>	* of all entries using the given reducer to combine values,
4091	>	* or null if none.
4092	>	*
4093	>	* @param transformer a function returning the transformation
4094	>	* for an element, or null of there is no transformation (in
4095	>	* which case it is not combined).
4096	>	* @param reducer a commutative associative combining function
4097	>	* @return the result of accumulating the given transformation
4098	>	* of all entries
4099	>	*/
4100	>	public <U> U reduceEntries(Fun<Map.Entry<K,V>, ? extends U> transformer,
4101	>	BiFun<? super U, ? super U, ? extends U> reducer) {
4102	>	return fjp.invoke(ForkJoinTasks.reduceEntries
4103	>	(ConcurrentHashMap.this, transformer, reducer));
4104	>	}
4105	>
4106	>	/**
4107	>	* Returns the result of accumulating the given transformation
4108	>	* of all entries using the given reducer to combine values,
4109	>	* and the given basis as an identity value.
4110	>	*
4111	>	* @param transformer a function returning the transformation
4112	>	* for an element
4113	>	* @param basis the identity (initial default value) for the reduction
4114	>	* @param reducer a commutative associative combining function
4115	>	* @return the result of accumulating the given transformation
4116	>	* of all entries
4117	>	*/
4118	>	public double reduceEntriesToDouble(ObjectToDouble<Map.Entry<K,V>> transformer,
4119	>	double basis,
4120	>	DoubleByDoubleToDouble reducer) {
4121	>	return fjp.invoke(ForkJoinTasks.reduceEntriesToDouble
4122	>	(ConcurrentHashMap.this, transformer, basis, reducer));
4123	>	}
4124	>
4125	>	/**
4126	>	* Returns the result of accumulating the given transformation
4127	>	* of all entries using the given reducer to combine values,
4128	>	* and the given basis as an identity value.
4129	>	*
4130	>	* @param transformer a function returning the transformation
4131	>	* for an element
4132	>	* @param basis the identity (initial default value) for the reduction
4133	>	* @param reducer a commutative associative combining function
4134	>	* @return  the result of accumulating the given transformation
4135	>	* of all entries
4136	>	*/
4137	>	public long reduceEntriesToLong(ObjectToLong<Map.Entry<K,V>> transformer,
4138	>	long basis,
4139	>	LongByLongToLong reducer) {
4140	>	return fjp.invoke(ForkJoinTasks.reduceEntriesToLong
4141	>	(ConcurrentHashMap.this, transformer, basis, reducer));
4142	>	}
4143	>
4144	>	/**
4145	>	* Returns the result of accumulating the given transformation
4146	>	* of all entries using the given reducer to combine values,
4147	>	* and the given basis as an identity value.
4148	>	*
4149	>	* @param transformer a function returning the transformation
4150	>	* for an element
4151	>	* @param basis the identity (initial default value) for the reduction
4152	>	* @param reducer a commutative associative combining function
4153	>	* @return the result of accumulating the given transformation
4154	>	* of all entries
4155	>	*/
4156	>	public int reduceEntriesToInt(ObjectToInt<Map.Entry<K,V>> transformer,
4157	>	int basis,
4158	>	IntByIntToInt reducer) {
4159	>	return fjp.invoke(ForkJoinTasks.reduceEntriesToInt
4160	>	(ConcurrentHashMap.this, transformer, basis, reducer));
4161	>	}
4162	>	}
4163	>
4164	>	// ---------------------------------------------------------------------
4165	>
4166	>	/**
4167	>	* Predefined tasks for performing bulk parallel operations on
4168	>	* ConcurrentHashMaps. These tasks follow the forms and rules used
4169	>	* in class {@link Parallel}. Each method has the same name, but
4170	>	* returns a task rather than invoking it. These methods may be
4171	>	* useful in custom applications such as submitting a task without
4172	>	* waiting for completion, or combining with other tasks.
4173	>	*/
4174	>	public static class ForkJoinTasks {
4175	>	private ForkJoinTasks() {}
4176	>
4177	>	/**
4178	>	* Returns a task that when invoked, performs the given
4179	>	* action for each (key, value)
4180	>	*
4181	>	* @param map the map
4182	>	* @param action the action
4183	>	* @return the task
4184	>	*/
4185	>	public static <K,V> ForkJoinTask<Void> forEach
4186	>	(ConcurrentHashMap<K,V> map,
4187	>	BiAction<K,V> action) {
4188	>	if (action == null) throw new NullPointerException();
4189	>	return new ForEachMappingTask<K,V>(map, null, -1, action);
4190	>	}
4191	>
4192	>	/**
4193	>	* Returns a task that when invoked, performs the given
4194	>	* action for each non-null transformation of each (key, value)
4195	>	*
4196	>	* @param map the map
4197	>	* @param transformer a function returning the transformation
4198	>	* for an element, or null of there is no transformation (in
4199	>	* which case the action is not applied)
4200	>	* @param action the action
4201	>	* @return the task
4202	>	*/
4203	>	public static <K,V,U> ForkJoinTask<Void> forEach
4204	>	(ConcurrentHashMap<K,V> map,
4205	>	BiFun<? super K, ? super V, ? extends U> transformer,
4206	>	Action<U> action) {
4207	>	if (transformer == null || action == null)
4208	>	throw new NullPointerException();
4209	>	return new ForEachTransformedMappingTask<K,V,U>
4210	>	(map, null, -1, transformer, action);
4211	>	}
4212	>
4213	>	/**
4214	>	* Returns a task that when invoked, returns a non-null result
4215	>	* from applying the given search function on each (key,
4216	>	* value), or null if none. Upon success, further element
4217	>	* processing is suppressed and the results of any other
4218	>	* parallel invocations of the search function are ignored.
4219	>	*
4220	>	* @param map the map
4221	>	* @param searchFunction a function returning a non-null
4222	>	* result on success, else null
4223	>	* @return the task
4224	>	*/
4225	>	public static <K,V,U> ForkJoinTask<U> search
4226	>	(ConcurrentHashMap<K,V> map,
4227	>	BiFun<? super K, ? super V, ? extends U> searchFunction) {
4228	>	if (searchFunction == null) throw new NullPointerException();
4229	>	return new SearchMappingsTask<K,V,U>
4230	>	(map, null, -1, searchFunction,
4231	>	new AtomicReference<U>());
4232	>	}
4233	>
4234	>	/**
4235	>	* Returns a task that when invoked, returns the result of
4236	>	* accumulating the given transformation of all (key, value) pairs
4237	>	* using the given reducer to combine values, or null if none.
4238	>	*
4239	>	* @param map the map
4240	>	* @param transformer a function returning the transformation
4241	>	* for an element, or null of there is no transformation (in
4242	>	* which case it is not combined).
4243	>	* @param reducer a commutative associative combining function
4244	>	* @return the task
4245	>	*/
4246	>	public static <K,V,U> ForkJoinTask<U> reduce
4247	>	(ConcurrentHashMap<K,V> map,
4248	>	BiFun<? super K, ? super V, ? extends U> transformer,
4249	>	BiFun<? super U, ? super U, ? extends U> reducer) {
4250	>	if (transformer == null || reducer == null)
4251	>	throw new NullPointerException();
4252	>	return new MapReduceMappingsTask<K,V,U>
4253	>	(map, null, -1, null, transformer, reducer);
4254	>	}
4255	>
4256	>	/**
4257	>	* Returns a task that when invoked, returns the result of
4258	>	* accumulating the given transformation of all (key, value) pairs
4259	>	* using the given reducer to combine values, and the given
4260	>	* basis as an identity value.
4261	>	*
4262	>	* @param map the map
4263	>	* @param transformer a function returning the transformation
4264	>	* for an element
4265	>	* @param basis the identity (initial default value) for the reduction
4266	>	* @param reducer a commutative associative combining function
4267	>	* @return the task
4268	>	*/
4269	>	public static <K,V> ForkJoinTask<Double> reduceToDouble
4270	>	(ConcurrentHashMap<K,V> map,
4271	>	ObjectByObjectToDouble<? super K, ? super V> transformer,
4272	>	double basis,
4273	>	DoubleByDoubleToDouble reducer) {
4274	>	if (transformer == null || reducer == null)
4275	>	throw new NullPointerException();
4276	>	return new MapReduceMappingsToDoubleTask<K,V>
4277	>	(map, null, -1, null, transformer, basis, reducer);
4278	>	}
4279	>
4280	>	/**
4281	>	* Returns a task that when invoked, returns the result of
4282	>	* accumulating the given transformation of all (key, value) pairs
4283	>	* using the given reducer to combine values, and the given
4284	>	* basis as an identity value.
4285	>	*
4286	>	* @param map the map
4287	>	* @param transformer a function returning the transformation
4288	>	* for an element
4289	>	* @param basis the identity (initial default value) for the reduction
4290	>	* @param reducer a commutative associative combining function
4291	>	* @return the task
4292	>	*/
4293	>	public static <K,V> ForkJoinTask<Long> reduceToLong
4294	>	(ConcurrentHashMap<K,V> map,
4295	>	ObjectByObjectToLong<? super K, ? super V> transformer,
4296	>	long basis,
4297	>	LongByLongToLong reducer) {
4298	>	if (transformer == null || reducer == null)
4299	>	throw new NullPointerException();
4300	>	return new MapReduceMappingsToLongTask<K,V>
4301	>	(map, null, -1, null, transformer, basis, reducer);
4302	>	}
4303	>
4304	>	/**
4305	>	* Returns a task that when invoked, returns the result of
4306	>	* accumulating the given transformation of all (key, value) pairs
4307	>	* using the given reducer to combine values, and the given
4308	>	* basis as an identity value.
4309	>	*
4310	>	* @param transformer a function returning the transformation
4311	>	* for an element
4312	>	* @param basis the identity (initial default value) for the reduction
4313	>	* @param reducer a commutative associative combining function
4314	>	* @return the task
4315	>	*/
4316	>	public static <K,V> ForkJoinTask<Integer> reduceToInt
4317	>	(ConcurrentHashMap<K,V> map,
4318	>	ObjectByObjectToInt<? super K, ? super V> transformer,
4319	>	int basis,
4320	>	IntByIntToInt reducer) {
4321	>	if (transformer == null || reducer == null)
4322	>	throw new NullPointerException();
4323	>	return new MapReduceMappingsToIntTask<K,V>
4324	>	(map, null, -1, null, transformer, basis, reducer);
4325	>	}
4326	>
4327	>	/**
4328	>	* Returns a task that when invoked, performs the given action
4329	>	* for each key.
4330	>	*
4331	>	* @param map the map
4332	>	* @param action the action
4333	>	* @return the task
4334	>	*/
4335	>	public static <K,V> ForkJoinTask<Void> forEachKey
4336	>	(ConcurrentHashMap<K,V> map,
4337	>	Action<K> action) {
4338	>	if (action == null) throw new NullPointerException();
4339	>	return new ForEachKeyTask<K,V>(map, null, -1, action);
4340	>	}
4341	>
4342	>	/**
4343	>	* Returns a task that when invoked, performs the given action
4344	>	* for each non-null transformation of each key.
4345	>	*
4346	>	* @param map the map
4347	>	* @param transformer a function returning the transformation
4348	>	* for an element, or null of there is no transformation (in
4349	>	* which case the action is not applied)
4350	>	* @param action the action
4351	>	* @return the task
4352	>	*/
4353	>	public static <K,V,U> ForkJoinTask<Void> forEachKey
4354	>	(ConcurrentHashMap<K,V> map,
4355	>	Fun<? super K, ? extends U> transformer,
4356	>	Action<U> action) {
4357	>	if (transformer == null || action == null)
4358	>	throw new NullPointerException();
4359	>	return new ForEachTransformedKeyTask<K,V,U>
4360	>	(map, null, -1, transformer, action);
4361	>	}
4362	>
4363	>	/**
4364	>	* Returns a task that when invoked, returns a non-null result
4365	>	* from applying the given search function on each key, or
4366	>	* null if none.  Upon success, further element processing is
4367	>	* suppressed and the results of any other parallel
4368	>	* invocations of the search function are ignored.
4369	>	*
4370	>	* @param map the map
4371	>	* @param searchFunction a function returning a non-null
4372	>	* result on success, else null
4373	>	* @return the task
4374	>	*/
4375	>	public static <K,V,U> ForkJoinTask<U> searchKeys
4376	>	(ConcurrentHashMap<K,V> map,
4377	>	Fun<? super K, ? extends U> searchFunction) {
4378	>	if (searchFunction == null) throw new NullPointerException();
4379	>	return new SearchKeysTask<K,V,U>
4380	>	(map, null, -1, searchFunction,
4381	>	new AtomicReference<U>());
4382	>	}
4383	>
4384	>	/**
4385	>	* Returns a task that when invoked, returns the result of
4386	>	* accumulating all keys using the given reducer to combine
4387	>	* values, or null if none.
4388	>	*
4389	>	* @param map the map
4390	>	* @param reducer a commutative associative combining function
4391	>	* @return the task
4392	>	*/
4393	>	public static <K,V> ForkJoinTask<K> reduceKeys
4394	>	(ConcurrentHashMap<K,V> map,
4395	>	BiFun<? super K, ? super K, ? extends K> reducer) {
4396	>	if (reducer == null) throw new NullPointerException();
4397	>	return new ReduceKeysTask<K,V>
4398	>	(map, null, -1, null, reducer);
4399	>	}
4400	>
4401	>	/**
4402	>	* Returns a task that when invoked, returns the result of
4403	>	* accumulating the given transformation of all keys using the given
4404	>	* reducer to combine values, or null if none.
4405	>	*
4406	>	* @param map the map
4407	>	* @param transformer a function returning the transformation
4408	>	* for an element, or null of there is no transformation (in
4409	>	* which case it is not combined).
4410	>	* @param reducer a commutative associative combining function
4411	>	* @return the task
4412	>	*/
4413	>	public static <K,V,U> ForkJoinTask<U> reduceKeys
4414	>	(ConcurrentHashMap<K,V> map,
4415	>	Fun<? super K, ? extends U> transformer,
4416	>	BiFun<? super U, ? super U, ? extends U> reducer) {
4417	>	if (transformer == null || reducer == null)
4418	>	throw new NullPointerException();
4419	>	return new MapReduceKeysTask<K,V,U>
4420	>	(map, null, -1, null, transformer, reducer);
4421	>	}
4422	>
4423	>	/**
4424	>	* Returns a task that when invoked, returns the result of
4425	>	* accumulating the given transformation of all keys using the given
4426	>	* reducer to combine values, and the given basis as an
4427	>	* identity value.
4428	>	*
4429	>	* @param map the map
4430	>	* @param transformer a function returning the transformation
4431	>	* for an element
4432	>	* @param basis the identity (initial default value) for the reduction
4433	>	* @param reducer a commutative associative combining function
4434	>	* @return the task
4435	>	*/
4436	>	public static <K,V> ForkJoinTask<Double> reduceKeysToDouble
4437	>	(ConcurrentHashMap<K,V> map,
4438	>	ObjectToDouble<? super K> transformer,
4439	>	double basis,
4440	>	DoubleByDoubleToDouble reducer) {
4441	>	if (transformer == null || reducer == null)
4442	>	throw new NullPointerException();
4443	>	return new MapReduceKeysToDoubleTask<K,V>
4444	>	(map, null, -1, null, transformer, basis, reducer);
4445	>	}
4446	>
4447	>	/**
4448	>	* Returns a task that when invoked, returns the result of
4449	>	* accumulating the given transformation of all keys using the given
4450	>	* reducer to combine values, and the given basis as an
4451	>	* identity value.
4452	>	*
4453	>	* @param map the map
4454	>	* @param transformer a function returning the transformation
4455	>	* for an element
4456	>	* @param basis the identity (initial default value) for the reduction
4457	>	* @param reducer a commutative associative combining function
4458	>	* @return the task
4459	>	*/
4460	>	public static <K,V> ForkJoinTask<Long> reduceKeysToLong
4461	>	(ConcurrentHashMap<K,V> map,
4462	>	ObjectToLong<? super K> transformer,
4463	>	long basis,
4464	>	LongByLongToLong reducer) {
4465	>	if (transformer == null || reducer == null)
4466	>	throw new NullPointerException();
4467	>	return new MapReduceKeysToLongTask<K,V>
4468	>	(map, null, -1, null, transformer, basis, reducer);
4469	>	}
4470	>
4471	>	/**
4472	>	* Returns a task that when invoked, returns the result of
4473	>	* accumulating the given transformation of all keys using the given
4474	>	* reducer to combine values, and the given basis as an
4475	>	* identity value.
4476	>	*
4477	>	* @param map the map
4478	>	* @param transformer a function returning the transformation
4479	>	* for an element
4480	>	* @param basis the identity (initial default value) for the reduction
4481	>	* @param reducer a commutative associative combining function
4482	>	* @return the task
4483	>	*/
4484	>	public static <K,V> ForkJoinTask<Integer> reduceKeysToInt
4485	>	(ConcurrentHashMap<K,V> map,
4486	>	ObjectToInt<? super K> transformer,
4487	>	int basis,
4488	>	IntByIntToInt reducer) {
4489	>	if (transformer == null || reducer == null)
4490	>	throw new NullPointerException();
4491	>	return new MapReduceKeysToIntTask<K,V>
4492	>	(map, null, -1, null, transformer, basis, reducer);
4493	>	}
4494	>
4495	>	/**
4496	>	* Returns a task that when invoked, performs the given action
4497	>	* for each value.
4498	>	*
4499	>	* @param map the map
4500	>	* @param action the action
4501	>	*/
4502	>	public static <K,V> ForkJoinTask<Void> forEachValue
4503	>	(ConcurrentHashMap<K,V> map,
4504	>	Action<V> action) {
4505	>	if (action == null) throw new NullPointerException();
4506	>	return new ForEachValueTask<K,V>(map, null, -1, action);
4507	>	}
4508	>
4509	>	/**
4510	>	* Returns a task that when invoked, performs the given action
4511	>	* for each non-null transformation of each value.
4512	>	*
4513	>	* @param map the map
4514	>	* @param transformer a function returning the transformation
4515	>	* for an element, or null of there is no transformation (in
4516	>	* which case the action is not applied)
4517	>	* @param action the action
4518	>	*/
4519	>	public static <K,V,U> ForkJoinTask<Void> forEachValue
4520	>	(ConcurrentHashMap<K,V> map,
4521	>	Fun<? super V, ? extends U> transformer,
4522	>	Action<U> action) {
4523	>	if (transformer == null || action == null)
4524	>	throw new NullPointerException();
4525	>	return new ForEachTransformedValueTask<K,V,U>
4526	>	(map, null, -1, transformer, action);
4527	>	}
4528	>
4529	>	/**
4530	>	* Returns a task that when invoked, returns a non-null result
4531	>	* from applying the given search function on each value, or
4532	>	* null if none.  Upon success, further element processing is
4533	>	* suppressed and the results of any other parallel
4534	>	* invocations of the search function are ignored.
4535	>	*
4536	>	* @param map the map
4537	>	* @param searchFunction a function returning a non-null
4538	>	* result on success, else null
4539	>	* @return the task
4540	>	*
4541	>	*/
4542	>	public static <K,V,U> ForkJoinTask<U> searchValues
4543	>	(ConcurrentHashMap<K,V> map,
4544	>	Fun<? super V, ? extends U> searchFunction) {
4545	>	if (searchFunction == null) throw new NullPointerException();
4546	>	return new SearchValuesTask<K,V,U>
4547	>	(map, null, -1, searchFunction,
4548	>	new AtomicReference<U>());
4549	>	}
4550	>
4551	>	/**
4552	>	* Returns a task that when invoked, returns the result of
4553	>	* accumulating all values using the given reducer to combine
4554	>	* values, or null if none.
4555	>	*
4556	>	* @param map the map
4557	>	* @param reducer a commutative associative combining function
4558	>	* @return the task
4559	>	*/
4560	>	public static <K,V> ForkJoinTask<V> reduceValues
4561	>	(ConcurrentHashMap<K,V> map,
4562	>	BiFun<? super V, ? super V, ? extends V> reducer) {
4563	>	if (reducer == null) throw new NullPointerException();
4564	>	return new ReduceValuesTask<K,V>
4565	>	(map, null, -1, null, reducer);
4566	>	}
4567	>
4568	>	/**
4569	>	* Returns a task that when invoked, returns the result of
4570	>	* accumulating the given transformation of all values using the
4571	>	* given reducer to combine values, or null if none.
4572	>	*
4573	>	* @param map the map
4574	>	* @param transformer a function returning the transformation
4575	>	* for an element, or null of there is no transformation (in
4576	>	* which case it is not combined).
4577	>	* @param reducer a commutative associative combining function
4578	>	* @return the task
4579	>	*/
4580	>	public static <K,V,U> ForkJoinTask<U> reduceValues
4581	>	(ConcurrentHashMap<K,V> map,
4582	>	Fun<? super V, ? extends U> transformer,
4583	>	BiFun<? super U, ? super U, ? extends U> reducer) {
4584	>	if (transformer == null || reducer == null)
4585	>	throw new NullPointerException();
4586	>	return new MapReduceValuesTask<K,V,U>
4587	>	(map, null, -1, null, transformer, reducer);
4588	>	}
4589	>
4590	>	/**
4591	>	* Returns a task that when invoked, returns the result of
4592	>	* accumulating the given transformation of all values using the
4593	>	* given reducer to combine values, and the given basis as an
4594	>	* identity value.
4595	>	*
4596	>	* @param map the map
4597	>	* @param transformer a function returning the transformation
4598	>	* for an element
4599	>	* @param basis the identity (initial default value) for the reduction
4600	>	* @param reducer a commutative associative combining function
4601	>	* @return the task
4602	>	*/
4603	>	public static <K,V> ForkJoinTask<Double> reduceValuesToDouble
4604	>	(ConcurrentHashMap<K,V> map,
4605	>	ObjectToDouble<? super V> transformer,
4606	>	double basis,
4607	>	DoubleByDoubleToDouble reducer) {
4608	>	if (transformer == null || reducer == null)
4609	>	throw new NullPointerException();
4610	>	return new MapReduceValuesToDoubleTask<K,V>
4611	>	(map, null, -1, null, transformer, basis, reducer);
4612	>	}
4613	>
4614	>	/**
4615	>	* Returns a task that when invoked, returns the result of
4616	>	* accumulating the given transformation of all values using the
4617	>	* given reducer to combine values, and the given basis as an
4618	>	* identity value.
4619	>	*
4620	>	* @param map the map
4621	>	* @param transformer a function returning the transformation
4622	>	* for an element
4623	>	* @param basis the identity (initial default value) for the reduction
4624	>	* @param reducer a commutative associative combining function
4625	>	* @return the task
4626	>	*/
4627	>	public static <K,V> ForkJoinTask<Long> reduceValuesToLong
4628	>	(ConcurrentHashMap<K,V> map,
4629	>	ObjectToLong<? super V> transformer,
4630	>	long basis,
4631	>	LongByLongToLong reducer) {
4632	>	if (transformer == null || reducer == null)
4633	>	throw new NullPointerException();
4634	>	return new MapReduceValuesToLongTask<K,V>
4635	>	(map, null, -1, null, transformer, basis, reducer);
4636	>	}
4637	>
4638	>	/**
4639	>	* Returns a task that when invoked, returns the result of
4640	>	* accumulating the given transformation of all values using the
4641	>	* given reducer to combine values, and the given basis as an
4642	>	* identity value.
4643	>	*
4644	>	* @param map the map
4645	>	* @param transformer a function returning the transformation
4646	>	* for an element
4647	>	* @param basis the identity (initial default value) for the reduction
4648	>	* @param reducer a commutative associative combining function
4649	>	* @return the task
4650	>	*/
4651	>	public static <K,V> ForkJoinTask<Integer> reduceValuesToInt
4652	>	(ConcurrentHashMap<K,V> map,
4653	>	ObjectToInt<? super V> transformer,
4654	>	int basis,
4655	>	IntByIntToInt reducer) {
4656	>	if (transformer == null || reducer == null)
4657	>	throw new NullPointerException();
4658	>	return new MapReduceValuesToIntTask<K,V>
4659	>	(map, null, -1, null, transformer, basis, reducer);
4660	>	}
4661	>
4662	>	/**
4663	>	* Returns a task that when invoked, perform the given action
4664	>	* for each entry.
4665	>	*
4666	>	* @param map the map
4667	>	* @param action the action
4668	>	*/
4669	>	public static <K,V> ForkJoinTask<Void> forEachEntry
4670	>	(ConcurrentHashMap<K,V> map,
4671	>	Action<Map.Entry<K,V>> action) {
4672	>	if (action == null) throw new NullPointerException();
4673	>	return new ForEachEntryTask<K,V>(map, null, -1, action);
4674	>	}
4675	>
4676	>	/**
4677	>	* Returns a task that when invoked, perform the given action
4678	>	* for each non-null transformation of each entry.
4679	>	*
4680	>	* @param map the map
4681	>	* @param transformer a function returning the transformation
4682	>	* for an element, or null of there is no transformation (in
4683	>	* which case the action is not applied)
4684	>	* @param action the action
4685	>	*/
4686	>	public static <K,V,U> ForkJoinTask<Void> forEachEntry
4687	>	(ConcurrentHashMap<K,V> map,
4688	>	Fun<Map.Entry<K,V>, ? extends U> transformer,
4689	>	Action<U> action) {
4690	>	if (transformer == null || action == null)
4691	>	throw new NullPointerException();
4692	>	return new ForEachTransformedEntryTask<K,V,U>
4693	>	(map, null, -1, transformer, action);
4694	>	}
4695	>
4696	>	/**
4697	>	* Returns a task that when invoked, returns a non-null result
4698	>	* from applying the given search function on each entry, or
4699	>	* null if none.  Upon success, further element processing is
4700	>	* suppressed and the results of any other parallel
4701	>	* invocations of the search function are ignored.
4702	>	*
4703	>	* @param map the map
4704	>	* @param searchFunction a function returning a non-null
4705	>	* result on success, else null
4706	>	* @return the task
4707	>	*
4708	>	*/
4709	>	public static <K,V,U> ForkJoinTask<U> searchEntries
4710	>	(ConcurrentHashMap<K,V> map,
4711	>	Fun<Map.Entry<K,V>, ? extends U> searchFunction) {
4712	>	if (searchFunction == null) throw new NullPointerException();
4713	>	return new SearchEntriesTask<K,V,U>
4714	>	(map, null, -1, searchFunction,
4715	>	new AtomicReference<U>());
4716	>	}
4717	>
4718	>	/**
4719	>	* Returns a task that when invoked, returns the result of
4720	>	* accumulating all entries using the given reducer to combine
4721	>	* values, or null if none.
4722	>	*
4723	>	* @param map the map
4724	>	* @param reducer a commutative associative combining function
4725	>	* @return the task
4726	>	*/
4727	>	public static <K,V> ForkJoinTask<Map.Entry<K,V>> reduceEntries
4728	>	(ConcurrentHashMap<K,V> map,
4729	>	BiFun<Map.Entry<K,V>, Map.Entry<K,V>, ? extends Map.Entry<K,V>> reducer) {
4730	>	if (reducer == null) throw new NullPointerException();
4731	>	return new ReduceEntriesTask<K,V>
4732	>	(map, null, -1, null, reducer);
4733	>	}
4734	>
4735	>	/**
4736	>	* Returns a task that when invoked, returns the result of
4737	>	* accumulating the given transformation of all entries using the
4738	>	* given reducer to combine values, or null if none.
4739	>	*
4740	>	* @param map the map
4741	>	* @param transformer a function returning the transformation
4742	>	* for an element, or null of there is no transformation (in
4743	>	* which case it is not combined).
4744	>	* @param reducer a commutative associative combining function
4745	>	* @return the task
4746	>	*/
4747	>	public static <K,V,U> ForkJoinTask<U> reduceEntries
4748	>	(ConcurrentHashMap<K,V> map,
4749	>	Fun<Map.Entry<K,V>, ? extends U> transformer,
4750	>	BiFun<? super U, ? super U, ? extends U> reducer) {
4751	>	if (transformer == null || reducer == null)
4752	>	throw new NullPointerException();
4753	>	return new MapReduceEntriesTask<K,V,U>
4754	>	(map, null, -1, null, transformer, reducer);
4755	>	}
4756	>
4757	>	/**
4758	>	* Returns a task that when invoked, returns the result of
4759	>	* accumulating the given transformation of all entries using the
4760	>	* given reducer to combine values, and the given basis as an
4761	>	* identity value.
4762	>	*
4763	>	* @param map the map
4764	>	* @param transformer a function returning the transformation
4765	>	* for an element
4766	>	* @param basis the identity (initial default value) for the reduction
4767	>	* @param reducer a commutative associative combining function
4768	>	* @return the task
4769	>	*/
4770	>	public static <K,V> ForkJoinTask<Double> reduceEntriesToDouble
4771	>	(ConcurrentHashMap<K,V> map,
4772	>	ObjectToDouble<Map.Entry<K,V>> transformer,
4773	>	double basis,
4774	>	DoubleByDoubleToDouble reducer) {
4775	>	if (transformer == null || reducer == null)
4776	>	throw new NullPointerException();
4777	>	return new MapReduceEntriesToDoubleTask<K,V>
4778	>	(map, null, -1, null, transformer, basis, reducer);
4779	>	}
4780	>
4781	>	/**
4782	>	* Returns a task that when invoked, returns the result of
4783	>	* accumulating the given transformation of all entries using the
4784	>	* given reducer to combine values, and the given basis as an
4785	>	* identity value.
4786	>	*
4787	>	* @param map the map
4788	>	* @param transformer a function returning the transformation
4789	>	* for an element
4790	>	* @param basis the identity (initial default value) for the reduction
4791	>	* @param reducer a commutative associative combining function
4792	>	* @return the task
4793	>	*/
4794	>	public static <K,V> ForkJoinTask<Long> reduceEntriesToLong
4795	>	(ConcurrentHashMap<K,V> map,
4796	>	ObjectToLong<Map.Entry<K,V>> transformer,
4797	>	long basis,
4798	>	LongByLongToLong reducer) {
4799	>	if (transformer == null || reducer == null)
4800	>	throw new NullPointerException();
4801	>	return new MapReduceEntriesToLongTask<K,V>
4802	>	(map, null, -1, null, transformer, basis, reducer);
4803	>	}
4804	>
4805	>	/**
4806	>	* Returns a task that when invoked, returns the result of
4807	>	* accumulating the given transformation of all entries using the
4808	>	* given reducer to combine values, and the given basis as an
4809	>	* identity value.
4810	>	*
4811	>	* @param map the map
4812	>	* @param transformer a function returning the transformation
4813	>	* for an element
4814	>	* @param basis the identity (initial default value) for the reduction
4815	>	* @param reducer a commutative associative combining function
4816	>	* @return the task
4817	>	*/
4818	>	public static <K,V> ForkJoinTask<Integer> reduceEntriesToInt
4819	>	(ConcurrentHashMap<K,V> map,
4820	>	ObjectToInt<Map.Entry<K,V>> transformer,
4821	>	int basis,
4822	>	IntByIntToInt reducer) {
4823	>	if (transformer == null || reducer == null)
4824	>	throw new NullPointerException();
4825	>	return new MapReduceEntriesToIntTask<K,V>
4826	>	(map, null, -1, null, transformer, basis, reducer);
4827	>	}
4828	>	}
4829	>
4830	>	// -------------------------------------------------------
4831	>
4832	>	/**
4833	>	* Base for FJ tasks for bulk operations. This adds a variant of
4834	>	* CountedCompleters and some split and merge bookkeeping to
4835	>	* iterator functionality. The forEach and reduce methods are
4836	>	* similar to those illustrated in CountedCompleter documentation,
4837	>	* except that bottom-up reduction completions perform them within
4838	>	* their compute methods. The search methods are like forEach
4839	>	* except they continually poll for success and exit early.  Also,
4840	>	* exceptions are handled in a simpler manner, by just trying to
4841	>	* complete root task exceptionally.
4842	>	*/
4843	>	@SuppressWarnings("serial") static abstract class BulkTask<K,V,R> extends Traverser<K,V,R> {
4844	>	final BulkTask<K,V,?> parent;  // completion target
4845	>	int batch;                     // split control; -1 for unknown
4846	>	int pending;                   // completion control
4847	>
4848	>	BulkTask(ConcurrentHashMap<K,V> map, BulkTask<K,V,?> parent,
4849	>	int batch) {
4850	>	super(map);
4851	>	this.parent = parent;
4852	>	this.batch = batch;
4853	>	if (parent != null && map != null) { // split parent
4854	>	Node[] t;
4855	>	if ((t = parent.tab) == null &&
4856	>	(t = parent.tab = map.table) != null)
4857	>	parent.baseLimit = parent.baseSize = t.length;
4858	>	this.tab = t;
4859	>	this.baseSize = parent.baseSize;
4860	>	int hi = this.baseLimit = parent.baseLimit;
4861	>	parent.baseLimit = this.index = this.baseIndex =
4862	>	(hi + parent.baseIndex + 1) >>> 1;
4863	>	}
4864	>	}
4865	>
4866	>	// FJ methods
4867	>
4868	>	/**
4869	>	* Propagates completion. Note that all reduce actions
4870	>	* bypass this method to combine while completing.
4871	>	*/
4872	>	final void tryComplete() {
4873	>	BulkTask<K,V,?> a = this, s = a;
4874	>	for (int c;;) {
4875	>	if ((c = a.pending) == 0) {
4876	>	if ((a = (s = a).parent) == null) {
4877	>	s.quietlyComplete();
4878	>	break;
4879	>	}
4880	>	}
4881	>	else if (U.compareAndSwapInt(a, PENDING, c, c - 1))
4882	>	break;
4883	>	}
4884	>	}
4885	>
4886	>	/**
4887	>	* Forces root task to complete.
4888	>	* @param ex if null, complete normally, else exceptionally
4889	>	* @return false to simplify use
4890	>	*/
4891	>	final boolean tryCompleteComputation(Throwable ex) {
4892	>	for (BulkTask<K,V,?> a = this;;) {
4893	>	BulkTask<K,V,?> p = a.parent;
4894	>	if (p == null) {
4895	>	if (ex != null)
4896	>	a.completeExceptionally(ex);
4897	>	else
4898	>	a.quietlyComplete();
4899	>	return false;
4900	>	}
4901	>	a = p;
4902	>	}
4903	>	}
4904	>
4905	>	/**
4906	>	* Version of tryCompleteComputation for function screening checks
4907	>	*/
4908	>	final boolean abortOnNullFunction() {
4909	>	return tryCompleteComputation(new Error("Unexpected null function"));
4910	>	}
4911	>
4912	>	// utilities
4913	>
4914	>	/** CompareAndSet pending count */
4915	>	final boolean casPending(int cmp, int val) {
4916	>	return U.compareAndSwapInt(this, PENDING, cmp, val);
4917	>	}
4918	>
4919	>	/**
4920	>	* Returns approx exp2 of the number of times (minus one) to
4921	>	* split task by two before executing leaf action. This value
4922	>	* is faster to compute and more convenient to use as a guide
4923	>	* to splitting than is the depth, since it is used while
4924	>	* dividing by two anyway.
4925	>	*/
4926	>	final int batch() {
4927	>	ConcurrentHashMap<K, V> m; int b; Node[] t;
4928	>	if ((b = batch) < 0 && (m = map) != null) { // force initialization
4929	>	if ((t = tab) == null && (t = tab = m.table) != null)
4930	>	baseLimit = baseSize = t.length;
4931	>	if (t != null) {
4932	>	long n = m.counter.sum();
4933	>	int sp = getPool().getParallelism() << 3; // slack of 8
4934	>	b = batch = (n <= 0L) ? 0 : (n < (long)sp) ? (int)n : sp;
4935	>	}
4936	>	}
4937	>	return b;
4938	>	}
4939	>
4940	>	/**
4941	>	* Returns exportable snapshot entry.
4942	>	*/
4943	>	static <K,V> AbstractMap.SimpleEntry<K,V> entryFor(K k, V v) {
4944	>	return new AbstractMap.SimpleEntry<K,V>(k, v);
4945	>	}
4946	>
4947	>	// Unsafe mechanics
4948	>	private static final sun.misc.Unsafe U;
4949	>	private static final long PENDING;
4950	>	static {
4951	>	try {
4952	>	U = sun.misc.Unsafe.getUnsafe();
4953	>	PENDING = U.objectFieldOffset
4954	>	(BulkTask.class.getDeclaredField("pending"));
4955	>	} catch (Exception e) {
4956	>	throw new Error(e);
4957	>	}
4958	>	}
4959	>	}
4960	>
4961	>	/*
4962	>	* Task classes. Coded in a regular but ugly format/style to
4963	>	* simplify checks that each variant differs in the right way from
4964	>	* others.
4965	>	*/
4966	>
4967	>	@SuppressWarnings("serial") static final class ForEachKeyTask<K,V>
4968	>	extends BulkTask<K,V,Void> {
4969	>	final Action<K> action;
4970	>	ForEachKeyTask
4971	>	(ConcurrentHashMap<K,V> m, BulkTask<K,V,?> p, int b,
4972	>	Action<K> action) {
4973	>	super(m, p, b);
4974	>	this.action = action;
4975	>	}
4976	>	@SuppressWarnings("unchecked") public final boolean exec() {
4977	>	final Action<K> action = this.action;
4978	>	if (action == null)
4979	>	return abortOnNullFunction();
4980	>	try {
4981	>	int b = batch(), c;
4982	>	while (b > 1 && baseIndex != baseLimit) {
4983	>	do {} while (!casPending(c = pending, c+1));
4984	>	new ForEachKeyTask<K,V>(map, this, b >>>= 1, action).fork();
4985	>	}
4986	>	while (advance() != null)
4987	>	action.apply((K)nextKey);
4988	>	tryComplete();
4989	>	} catch (Throwable ex) {
4990	>	return tryCompleteComputation(ex);
4991	>	}
4992	>	return false;
4993	>	}
4994	>	}
4995	>
4996	>	@SuppressWarnings("serial") static final class ForEachValueTask<K,V>
4997	>	extends BulkTask<K,V,Void> {
4998	>	final Action<V> action;
4999	>	ForEachValueTask
5000	>	(ConcurrentHashMap<K,V> m, BulkTask<K,V,?> p, int b,
5001	>	Action<V> action) {
5002	>	super(m, p, b);
5003	>	this.action = action;
5004	>	}
5005	>	@SuppressWarnings("unchecked") public final boolean exec() {
5006	>	final Action<V> action = this.action;
5007	>	if (action == null)
5008	>	return abortOnNullFunction();
5009	>	try {
5010	>	int b = batch(), c;
5011	>	while (b > 1 && baseIndex != baseLimit) {
5012	>	do {} while (!casPending(c = pending, c+1));
5013	>	new ForEachValueTask<K,V>(map, this, b >>>= 1, action).fork();
5014	>	}
5015	>	Object v;
5016	>	while ((v = advance()) != null)
5017	>	action.apply((V)v);
5018	>	tryComplete();
5019	>	} catch (Throwable ex) {
5020	>	return tryCompleteComputation(ex);
5021	>	}
5022	>	return false;
5023	>	}
5024	>	}
5025	>
5026	>	@SuppressWarnings("serial") static final class ForEachEntryTask<K,V>
5027	>	extends BulkTask<K,V,Void> {
5028	>	final Action<Entry<K,V>> action;
5029	>	ForEachEntryTask
5030	>	(ConcurrentHashMap<K,V> m, BulkTask<K,V,?> p, int b,
5031	>	Action<Entry<K,V>> action) {
5032	>	super(m, p, b);
5033	>	this.action = action;
5034	>	}
5035	>	@SuppressWarnings("unchecked") public final boolean exec() {
5036	>	final Action<Entry<K,V>> action = this.action;
5037	>	if (action == null)
5038	>	return abortOnNullFunction();
5039	>	try {
5040	>	int b = batch(), c;
5041	>	while (b > 1 && baseIndex != baseLimit) {
5042	>	do {} while (!casPending(c = pending, c+1));
5043	>	new ForEachEntryTask<K,V>(map, this, b >>>= 1, action).fork();
5044	>	}
5045	>	Object v;
5046	>	while ((v = advance()) != null)
5047	>	action.apply(entryFor((K)nextKey, (V)v));
5048	>	tryComplete();
5049	>	} catch (Throwable ex) {
5050	>	return tryCompleteComputation(ex);
5051	>	}
5052	>	return false;
5053	>	}
5054	>	}
5055	>
5056	>	@SuppressWarnings("serial") static final class ForEachMappingTask<K,V>
5057	>	extends BulkTask<K,V,Void> {
5058	>	final BiAction<K,V> action;
5059	>	ForEachMappingTask
5060	>	(ConcurrentHashMap<K,V> m, BulkTask<K,V,?> p, int b,
5061	>	BiAction<K,V> action) {
5062	>	super(m, p, b);
5063	>	this.action = action;
5064	>	}
5065	>	@SuppressWarnings("unchecked") public final boolean exec() {
5066	>	final BiAction<K,V> action = this.action;
5067	>	if (action == null)
5068	>	return abortOnNullFunction();
5069	>	try {
5070	>	int b = batch(), c;
5071	>	while (b > 1 && baseIndex != baseLimit) {
5072	>	do {} while (!casPending(c = pending, c+1));
5073	>	new ForEachMappingTask<K,V>(map, this, b >>>= 1,
5074	>	action).fork();
5075	>	}
5076	>	Object v;
5077	>	while ((v = advance()) != null)
5078	>	action.apply((K)nextKey, (V)v);
5079	>	tryComplete();
5080	>	} catch (Throwable ex) {
5081	>	return tryCompleteComputation(ex);
5082	>	}
5083	>	return false;
5084		}
5085		}
5086	+
5087	+	@SuppressWarnings("serial") static final class ForEachTransformedKeyTask<K,V,U>
5088	+	extends BulkTask<K,V,Void> {
5089	+	final Fun<? super K, ? extends U> transformer;
5090	+	final Action<U> action;
5091	+	ForEachTransformedKeyTask
5092	+	(ConcurrentHashMap<K,V> m, BulkTask<K,V,?> p, int b,
5093	+	Fun<? super K, ? extends U> transformer,
5094	+	Action<U> action) {
5095	+	super(m, p, b);
5096	+	this.transformer = transformer;
5097	+	this.action = action;
5098	+
5099	+	}
5100	+	@SuppressWarnings("unchecked") public final boolean exec() {
5101	+	final Fun<? super K, ? extends U> transformer =
5102	+	this.transformer;
5103	+	final Action<U> action = this.action;
5104	+	if (transformer == null || action == null)
5105	+	return abortOnNullFunction();
5106	+	try {
5107	+	int b = batch(), c;
5108	+	while (b > 1 && baseIndex != baseLimit) {
5109	+	do {} while (!casPending(c = pending, c+1));
5110	+	new ForEachTransformedKeyTask<K,V,U>
5111	+	(map, this, b >>>= 1, transformer, action).fork();
5112	+	}
5113	+	U u;
5114	+	while (advance() != null) {
5115	+	if ((u = transformer.apply((K)nextKey)) != null)
5116	+	action.apply(u);
5117	+	}
5118	+	tryComplete();
5119	+	} catch (Throwable ex) {
5120	+	return tryCompleteComputation(ex);
5121	+	}
5122	+	return false;
5123	+	}
5124	+	}
5125	+
5126	+	@SuppressWarnings("serial") static final class ForEachTransformedValueTask<K,V,U>
5127	+	extends BulkTask<K,V,Void> {
5128	+	final Fun<? super V, ? extends U> transformer;
5129	+	final Action<U> action;
5130	+	ForEachTransformedValueTask
5131	+	(ConcurrentHashMap<K,V> m, BulkTask<K,V,?> p, int b,
5132	+	Fun<? super V, ? extends U> transformer,
5133	+	Action<U> action) {
5134	+	super(m, p, b);
5135	+	this.transformer = transformer;
5136	+	this.action = action;
5137	+
5138	+	}
5139	+	@SuppressWarnings("unchecked") public final boolean exec() {
5140	+	final Fun<? super V, ? extends U> transformer =
5141	+	this.transformer;
5142	+	final Action<U> action = this.action;
5143	+	if (transformer == null || action == null)
5144	+	return abortOnNullFunction();
5145	+	try {
5146	+	int b = batch(), c;
5147	+	while (b > 1 && baseIndex != baseLimit) {
5148	+	do {} while (!casPending(c = pending, c+1));
5149	+	new ForEachTransformedValueTask<K,V,U>
5150	+	(map, this, b >>>= 1, transformer, action).fork();
5151	+	}
5152	+	Object v; U u;
5153	+	while ((v = advance()) != null) {
5154	+	if ((u = transformer.apply((V)v)) != null)
5155	+	action.apply(u);
5156	+	}
5157	+	tryComplete();
5158	+	} catch (Throwable ex) {
5159	+	return tryCompleteComputation(ex);
5160	+	}
5161	+	return false;
5162	+	}
5163	+	}
5164	+
5165	+	@SuppressWarnings("serial") static final class ForEachTransformedEntryTask<K,V,U>
5166	+	extends BulkTask<K,V,Void> {
5167	+	final Fun<Map.Entry<K,V>, ? extends U> transformer;
5168	+	final Action<U> action;
5169	+	ForEachTransformedEntryTask
5170	+	(ConcurrentHashMap<K,V> m, BulkTask<K,V,?> p, int b,
5171	+	Fun<Map.Entry<K,V>, ? extends U> transformer,
5172	+	Action<U> action) {
5173	+	super(m, p, b);
5174	+	this.transformer = transformer;
5175	+	this.action = action;
5176	+
5177	+	}
5178	+	@SuppressWarnings("unchecked") public final boolean exec() {
5179	+	final Fun<Map.Entry<K,V>, ? extends U> transformer =
5180	+	this.transformer;
5181	+	final Action<U> action = this.action;
5182	+	if (transformer == null || action == null)
5183	+	return abortOnNullFunction();
5184	+	try {
5185	+	int b = batch(), c;
5186	+	while (b > 1 && baseIndex != baseLimit) {
5187	+	do {} while (!casPending(c = pending, c+1));
5188	+	new ForEachTransformedEntryTask<K,V,U>
5189	+	(map, this, b >>>= 1, transformer, action).fork();
5190	+	}
5191	+	Object v; U u;
5192	+	while ((v = advance()) != null) {
5193	+	if ((u = transformer.apply(entryFor((K)nextKey, (V)v))) != null)
5194	+	action.apply(u);
5195	+	}
5196	+	tryComplete();
5197	+	} catch (Throwable ex) {
5198	+	return tryCompleteComputation(ex);
5199	+	}
5200	+	return false;
5201	+	}
5202	+	}
5203	+
5204	+	@SuppressWarnings("serial") static final class ForEachTransformedMappingTask<K,V,U>
5205	+	extends BulkTask<K,V,Void> {
5206	+	final BiFun<? super K, ? super V, ? extends U> transformer;
5207	+	final Action<U> action;
5208	+	ForEachTransformedMappingTask
5209	+	(ConcurrentHashMap<K,V> m, BulkTask<K,V,?> p, int b,
5210	+	BiFun<? super K, ? super V, ? extends U> transformer,
5211	+	Action<U> action) {
5212	+	super(m, p, b);
5213	+	this.transformer = transformer;
5214	+	this.action = action;
5215	+
5216	+	}
5217	+	@SuppressWarnings("unchecked") public final boolean exec() {
5218	+	final BiFun<? super K, ? super V, ? extends U> transformer =
5219	+	this.transformer;
5220	+	final Action<U> action = this.action;
5221	+	if (transformer == null || action == null)
5222	+	return abortOnNullFunction();
5223	+	try {
5224	+	int b = batch(), c;
5225	+	while (b > 1 && baseIndex != baseLimit) {
5226	+	do {} while (!casPending(c = pending, c+1));
5227	+	new ForEachTransformedMappingTask<K,V,U>
5228	+	(map, this, b >>>= 1, transformer, action).fork();
5229	+	}
5230	+	Object v; U u;
5231	+	while ((v = advance()) != null) {
5232	+	if ((u = transformer.apply((K)nextKey, (V)v)) != null)
5233	+	action.apply(u);
5234	+	}
5235	+	tryComplete();
5236	+	} catch (Throwable ex) {
5237	+	return tryCompleteComputation(ex);
5238	+	}
5239	+	return false;
5240	+	}
5241	+	}
5242	+
5243	+	@SuppressWarnings("serial") static final class SearchKeysTask<K,V,U>
5244	+	extends BulkTask<K,V,U> {
5245	+	final Fun<? super K, ? extends U> searchFunction;
5246	+	final AtomicReference<U> result;
5247	+	SearchKeysTask
5248	+	(ConcurrentHashMap<K,V> m, BulkTask<K,V,?> p, int b,
5249	+	Fun<? super K, ? extends U> searchFunction,
5250	+	AtomicReference<U> result) {
5251	+	super(m, p, b);
5252	+	this.searchFunction = searchFunction; this.result = result;
5253	+	}
5254	+	@SuppressWarnings("unchecked") public final boolean exec() {
5255	+	AtomicReference<U> result = this.result;
5256	+	final Fun<? super K, ? extends U> searchFunction =
5257	+	this.searchFunction;
5258	+	if (searchFunction == null || result == null)
5259	+	return abortOnNullFunction();
5260	+	try {
5261	+	int b = batch(), c;
5262	+	while (b > 1 && baseIndex != baseLimit && result.get() == null) {
5263	+	do {} while (!casPending(c = pending, c+1));
5264	+	new SearchKeysTask<K,V,U>(map, this, b >>>= 1,
5265	+	searchFunction, result).fork();
5266	+	}
5267	+	U u;
5268	+	while (result.get() == null && advance() != null) {
5269	+	if ((u = searchFunction.apply((K)nextKey)) != null) {
5270	+	if (result.compareAndSet(null, u))
5271	+	tryCompleteComputation(null);
5272	+	break;
5273	+	}
5274	+	}
5275	+	tryComplete();
5276	+	} catch (Throwable ex) {
5277	+	return tryCompleteComputation(ex);
5278	+	}
5279	+	return false;
5280	+	}
5281	+	public final U getRawResult() { return result.get(); }
5282	+	}
5283	+
5284	+	@SuppressWarnings("serial") static final class SearchValuesTask<K,V,U>
5285	+	extends BulkTask<K,V,U> {
5286	+	final Fun<? super V, ? extends U> searchFunction;
5287	+	final AtomicReference<U> result;
5288	+	SearchValuesTask
5289	+	(ConcurrentHashMap<K,V> m, BulkTask<K,V,?> p, int b,
5290	+	Fun<? super V, ? extends U> searchFunction,
5291	+	AtomicReference<U> result) {
5292	+	super(m, p, b);
5293	+	this.searchFunction = searchFunction; this.result = result;
5294	+	}
5295	+	@SuppressWarnings("unchecked") public final boolean exec() {
5296	+	AtomicReference<U> result = this.result;
5297	+	final Fun<? super V, ? extends U> searchFunction =
5298	+	this.searchFunction;
5299	+	if (searchFunction == null || result == null)
5300	+	return abortOnNullFunction();
5301	+	try {
5302	+	int b = batch(), c;
5303	+	while (b > 1 && baseIndex != baseLimit && result.get() == null) {
5304	+	do {} while (!casPending(c = pending, c+1));
5305	+	new SearchValuesTask<K,V,U>(map, this, b >>>= 1,
5306	+	searchFunction, result).fork();
5307	+	}
5308	+	Object v; U u;
5309	+	while (result.get() == null && (v = advance()) != null) {
5310	+	if ((u = searchFunction.apply((V)v)) != null) {
5311	+	if (result.compareAndSet(null, u))
5312	+	tryCompleteComputation(null);
5313	+	break;
5314	+	}
5315	+	}
5316	+	tryComplete();
5317	+	} catch (Throwable ex) {
5318	+	return tryCompleteComputation(ex);
5319	+	}
5320	+	return false;
5321	+	}
5322	+	public final U getRawResult() { return result.get(); }
5323	+	}
5324	+
5325	+	@SuppressWarnings("serial") static final class SearchEntriesTask<K,V,U>
5326	+	extends BulkTask<K,V,U> {
5327	+	final Fun<Entry<K,V>, ? extends U> searchFunction;
5328	+	final AtomicReference<U> result;
5329	+	SearchEntriesTask
5330	+	(ConcurrentHashMap<K,V> m, BulkTask<K,V,?> p, int b,
5331	+	Fun<Entry<K,V>, ? extends U> searchFunction,
5332	+	AtomicReference<U> result) {
5333	+	super(m, p, b);
5334	+	this.searchFunction = searchFunction; this.result = result;
5335	+	}
5336	+	@SuppressWarnings("unchecked") public final boolean exec() {
5337	+	AtomicReference<U> result = this.result;
5338	+	final Fun<Entry<K,V>, ? extends U> searchFunction =
5339	+	this.searchFunction;
5340	+	if (searchFunction == null || result == null)
5341	+	return abortOnNullFunction();
5342	+	try {
5343	+	int b = batch(), c;
5344	+	while (b > 1 && baseIndex != baseLimit && result.get() == null) {
5345	+	do {} while (!casPending(c = pending, c+1));
5346	+	new SearchEntriesTask<K,V,U>(map, this, b >>>= 1,
5347	+	searchFunction, result).fork();
5348	+	}
5349	+	Object v; U u;
5350	+	while (result.get() == null && (v = advance()) != null) {
5351	+	if ((u = searchFunction.apply(entryFor((K)nextKey, (V)v))) != null) {
5352	+	if (result.compareAndSet(null, u))
5353	+	tryCompleteComputation(null);
5354	+	break;
5355	+	}
5356	+	}
5357	+	tryComplete();
5358	+	} catch (Throwable ex) {
5359	+	return tryCompleteComputation(ex);
5360	+	}
5361	+	return false;
5362	+	}
5363	+	public final U getRawResult() { return result.get(); }
5364	+	}
5365	+
5366	+	@SuppressWarnings("serial") static final class SearchMappingsTask<K,V,U>
5367	+	extends BulkTask<K,V,U> {
5368	+	final BiFun<? super K, ? super V, ? extends U> searchFunction;
5369	+	final AtomicReference<U> result;
5370	+	SearchMappingsTask
5371	+	(ConcurrentHashMap<K,V> m, BulkTask<K,V,?> p, int b,
5372	+	BiFun<? super K, ? super V, ? extends U> searchFunction,
5373	+	AtomicReference<U> result) {
5374	+	super(m, p, b);
5375	+	this.searchFunction = searchFunction; this.result = result;
5376	+	}
5377	+	@SuppressWarnings("unchecked") public final boolean exec() {
5378	+	AtomicReference<U> result = this.result;
5379	+	final BiFun<? super K, ? super V, ? extends U> searchFunction =
5380	+	this.searchFunction;
5381	+	if (searchFunction == null || result == null)
5382	+	return abortOnNullFunction();
5383	+	try {
5384	+	int b = batch(), c;
5385	+	while (b > 1 && baseIndex != baseLimit && result.get() == null) {
5386	+	do {} while (!casPending(c = pending, c+1));
5387	+	new SearchMappingsTask<K,V,U>(map, this, b >>>= 1,
5388	+	searchFunction, result).fork();
5389	+	}
5390	+	Object v; U u;
5391	+	while (result.get() == null && (v = advance()) != null) {
5392	+	if ((u = searchFunction.apply((K)nextKey, (V)v)) != null) {
5393	+	if (result.compareAndSet(null, u))
5394	+	tryCompleteComputation(null);
5395	+	break;
5396	+	}
5397	+	}
5398	+	tryComplete();
5399	+	} catch (Throwable ex) {
5400	+	return tryCompleteComputation(ex);
5401	+	}
5402	+	return false;
5403	+	}
5404	+	public final U getRawResult() { return result.get(); }
5405	+	}
5406	+
5407	+	@SuppressWarnings("serial") static final class ReduceKeysTask<K,V>
5408	+	extends BulkTask<K,V,K> {
5409	+	final BiFun<? super K, ? super K, ? extends K> reducer;
5410	+	K result;
5411	+	ReduceKeysTask<K,V> rights, nextRight;
5412	+	ReduceKeysTask
5413	+	(ConcurrentHashMap<K,V> m, BulkTask<K,V,?> p, int b,
5414	+	ReduceKeysTask<K,V> nextRight,
5415	+	BiFun<? super K, ? super K, ? extends K> reducer) {
5416	+	super(m, p, b); this.nextRight = nextRight;
5417	+	this.reducer = reducer;
5418	+	}
5419	+	@SuppressWarnings("unchecked") public final boolean exec() {
5420	+	final BiFun<? super K, ? super K, ? extends K> reducer =
5421	+	this.reducer;
5422	+	if (reducer == null)
5423	+	return abortOnNullFunction();
5424	+	try {
5425	+	for (int c, b = batch(); b > 1 && baseIndex != baseLimit;) {
5426	+	do {} while (!casPending(c = pending, c+1));
5427	+	(rights = new ReduceKeysTask<K,V>
5428	+	(map, this, b >>>= 1, rights, reducer)).fork();
5429	+	}
5430	+	K r = null;
5431	+	while (advance() != null) {
5432	+	K u = (K)nextKey;
5433	+	r = (r == null) ? u : reducer.apply(r, u);
5434	+	}
5435	+	result = r;
5436	+	for (ReduceKeysTask<K,V> t = this, s;;) {
5437	+	int c; BulkTask<K,V,?> par; K tr, sr;
5438	+	if ((c = t.pending) == 0) {
5439	+	for (s = t.rights; s != null; s = t.rights = s.nextRight) {
5440	+	if ((sr = s.result) != null)
5441	+	t.result = ((tr = t.result) == null) ? sr : reducer.apply(tr, sr);
5442	+	}
5443	+	if ((par = t.parent) == null ||
5444	+	!(par instanceof ReduceKeysTask)) {
5445	+	t.quietlyComplete();
5446	+	break;
5447	+	}
5448	+	t = (ReduceKeysTask<K,V>)par;
5449	+	}
5450	+	else if (t.casPending(c, c - 1))
5451	+	break;
5452	+	}
5453	+	} catch (Throwable ex) {
5454	+	return tryCompleteComputation(ex);
5455	+	}
5456	+	return false;
5457	+	}
5458	+	public final K getRawResult() { return result; }
5459	+	}
5460	+
5461	+	@SuppressWarnings("serial") static final class ReduceValuesTask<K,V>
5462	+	extends BulkTask<K,V,V> {
5463	+	final BiFun<? super V, ? super V, ? extends V> reducer;
5464	+	V result;
5465	+	ReduceValuesTask<K,V> rights, nextRight;
5466	+	ReduceValuesTask
5467	+	(ConcurrentHashMap<K,V> m, BulkTask<K,V,?> p, int b,
5468	+	ReduceValuesTask<K,V> nextRight,
5469	+	BiFun<? super V, ? super V, ? extends V> reducer) {
5470	+	super(m, p, b); this.nextRight = nextRight;
5471	+	this.reducer = reducer;
5472	+	}
5473	+	@SuppressWarnings("unchecked") public final boolean exec() {
5474	+	final BiFun<? super V, ? super V, ? extends V> reducer =
5475	+	this.reducer;
5476	+	if (reducer == null)
5477	+	return abortOnNullFunction();
5478	+	try {
5479	+	for (int c, b = batch(); b > 1 && baseIndex != baseLimit;) {
5480	+	do {} while (!casPending(c = pending, c+1));
5481	+	(rights = new ReduceValuesTask<K,V>
5482	+	(map, this, b >>>= 1, rights, reducer)).fork();
5483	+	}
5484	+	V r = null;
5485	+	Object v;
5486	+	while ((v = advance()) != null) {
5487	+	V u = (V)v;
5488	+	r = (r == null) ? u : reducer.apply(r, u);
5489	+	}
5490	+	result = r;
5491	+	for (ReduceValuesTask<K,V> t = this, s;;) {
5492	+	int c; BulkTask<K,V,?> par; V tr, sr;
5493	+	if ((c = t.pending) == 0) {
5494	+	for (s = t.rights; s != null; s = t.rights = s.nextRight) {
5495	+	if ((sr = s.result) != null)
5496	+	t.result = ((tr = t.result) == null) ? sr : reducer.apply(tr, sr);
5497	+	}
5498	+	if ((par = t.parent) == null ||
5499	+	!(par instanceof ReduceValuesTask)) {
5500	+	t.quietlyComplete();
5501	+	break;
5502	+	}
5503	+	t = (ReduceValuesTask<K,V>)par;
5504	+	}
5505	+	else if (t.casPending(c, c - 1))
5506	+	break;
5507	+	}
5508	+	} catch (Throwable ex) {
5509	+	return tryCompleteComputation(ex);
5510	+	}
5511	+	return false;
5512	+	}
5513	+	public final V getRawResult() { return result; }
5514	+	}
5515	+
5516	+	@SuppressWarnings("serial") static final class ReduceEntriesTask<K,V>
5517	+	extends BulkTask<K,V,Map.Entry<K,V>> {
5518	+	final BiFun<Map.Entry<K,V>, Map.Entry<K,V>, ? extends Map.Entry<K,V>> reducer;
5519	+	Map.Entry<K,V> result;
5520	+	ReduceEntriesTask<K,V> rights, nextRight;
5521	+	ReduceEntriesTask
5522	+	(ConcurrentHashMap<K,V> m, BulkTask<K,V,?> p, int b,
5523	+	ReduceEntriesTask<K,V> nextRight,
5524	+	BiFun<Entry<K,V>, Map.Entry<K,V>, ? extends Map.Entry<K,V>> reducer) {
5525	+	super(m, p, b); this.nextRight = nextRight;
5526	+	this.reducer = reducer;
5527	+	}
5528	+	@SuppressWarnings("unchecked") public final boolean exec() {
5529	+	final BiFun<Map.Entry<K,V>, Map.Entry<K,V>, ? extends Map.Entry<K,V>> reducer =
5530	+	this.reducer;
5531	+	if (reducer == null)
5532	+	return abortOnNullFunction();
5533	+	try {
5534	+	for (int c, b = batch(); b > 1 && baseIndex != baseLimit;) {
5535	+	do {} while (!casPending(c = pending, c+1));
5536	+	(rights = new ReduceEntriesTask<K,V>
5537	+	(map, this, b >>>= 1, rights, reducer)).fork();
5538	+	}
5539	+	Map.Entry<K,V> r = null;
5540	+	Object v;
5541	+	while ((v = advance()) != null) {
5542	+	Map.Entry<K,V> u = entryFor((K)nextKey, (V)v);
5543	+	r = (r == null) ? u : reducer.apply(r, u);
5544	+	}
5545	+	result = r;
5546	+	for (ReduceEntriesTask<K,V> t = this, s;;) {
5547	+	int c; BulkTask<K,V,?> par; Map.Entry<K,V> tr, sr;
5548	+	if ((c = t.pending) == 0) {
5549	+	for (s = t.rights; s != null; s = t.rights = s.nextRight) {
5550	+	if ((sr = s.result) != null)
5551	+	t.result = ((tr = t.result) == null) ? sr : reducer.apply(tr, sr);
5552	+	}
5553	+	if ((par = t.parent) == null ||
5554	+	!(par instanceof ReduceEntriesTask)) {
5555	+	t.quietlyComplete();
5556	+	break;
5557	+	}
5558	+	t = (ReduceEntriesTask<K,V>)par;
5559	+	}
5560	+	else if (t.casPending(c, c - 1))
5561	+	break;
5562	+	}
5563	+	} catch (Throwable ex) {
5564	+	return tryCompleteComputation(ex);
5565	+	}
5566	+	return false;
5567	+	}
5568	+	public final Map.Entry<K,V> getRawResult() { return result; }
5569	+	}
5570	+
5571	+	@SuppressWarnings("serial") static final class MapReduceKeysTask<K,V,U>
5572	+	extends BulkTask<K,V,U> {
5573	+	final Fun<? super K, ? extends U> transformer;
5574	+	final BiFun<? super U, ? super U, ? extends U> reducer;
5575	+	U result;
5576	+	MapReduceKeysTask<K,V,U> rights, nextRight;
5577	+	MapReduceKeysTask
5578	+	(ConcurrentHashMap<K,V> m, BulkTask<K,V,?> p, int b,
5579	+	MapReduceKeysTask<K,V,U> nextRight,
5580	+	Fun<? super K, ? extends U> transformer,
5581	+	BiFun<? super U, ? super U, ? extends U> reducer) {
5582	+	super(m, p, b); this.nextRight = nextRight;
5583	+	this.transformer = transformer;
5584	+	this.reducer = reducer;
5585	+	}
5586	+	@SuppressWarnings("unchecked") public final boolean exec() {
5587	+	final Fun<? super K, ? extends U> transformer =
5588	+	this.transformer;
5589	+	final BiFun<? super U, ? super U, ? extends U> reducer =
5590	+	this.reducer;
5591	+	if (transformer == null || reducer == null)
5592	+	return abortOnNullFunction();
5593	+	try {
5594	+	for (int c, b = batch(); b > 1 && baseIndex != baseLimit;) {
5595	+	do {} while (!casPending(c = pending, c+1));
5596	+	(rights = new MapReduceKeysTask<K,V,U>
5597	+	(map, this, b >>>= 1, rights, transformer, reducer)).fork();
5598	+	}
5599	+	U r = null, u;
5600	+	while (advance() != null) {
5601	+	if ((u = transformer.apply((K)nextKey)) != null)
5602	+	r = (r == null) ? u : reducer.apply(r, u);
5603	+	}
5604	+	result = r;
5605	+	for (MapReduceKeysTask<K,V,U> t = this, s;;) {
5606	+	int c; BulkTask<K,V,?> par; U tr, sr;
5607	+	if ((c = t.pending) == 0) {
5608	+	for (s = t.rights; s != null; s = t.rights = s.nextRight) {
5609	+	if ((sr = s.result) != null)
5610	+	t.result = ((tr = t.result) == null) ? sr : reducer.apply(tr, sr);
5611	+	}
5612	+	if ((par = t.parent) == null ||
5613	+	!(par instanceof MapReduceKeysTask)) {
5614	+	t.quietlyComplete();
5615	+	break;
5616	+	}
5617	+	t = (MapReduceKeysTask<K,V,U>)par;
5618	+	}
5619	+	else if (t.casPending(c, c - 1))
5620	+	break;
5621	+	}
5622	+	} catch (Throwable ex) {
5623	+	return tryCompleteComputation(ex);
5624	+	}
5625	+	return false;
5626	+	}
5627	+	public final U getRawResult() { return result; }
5628	+	}
5629	+
5630	+	@SuppressWarnings("serial") static final class MapReduceValuesTask<K,V,U>
5631	+	extends BulkTask<K,V,U> {
5632	+	final Fun<? super V, ? extends U> transformer;
5633	+	final BiFun<? super U, ? super U, ? extends U> reducer;
5634	+	U result;
5635	+	MapReduceValuesTask<K,V,U> rights, nextRight;
5636	+	MapReduceValuesTask
5637	+	(ConcurrentHashMap<K,V> m, BulkTask<K,V,?> p, int b,
5638	+	MapReduceValuesTask<K,V,U> nextRight,
5639	+	Fun<? super V, ? extends U> transformer,
5640	+	BiFun<? super U, ? super U, ? extends U> reducer) {
5641	+	super(m, p, b); this.nextRight = nextRight;
5642	+	this.transformer = transformer;
5643	+	this.reducer = reducer;
5644	+	}
5645	+	@SuppressWarnings("unchecked") public final boolean exec() {
5646	+	final Fun<? super V, ? extends U> transformer =
5647	+	this.transformer;
5648	+	final BiFun<? super U, ? super U, ? extends U> reducer =
5649	+	this.reducer;
5650	+	if (transformer == null || reducer == null)
5651	+	return abortOnNullFunction();
5652	+	try {
5653	+	for (int c, b = batch(); b > 1 && baseIndex != baseLimit;) {
5654	+	do {} while (!casPending(c = pending, c+1));
5655	+	(rights = new MapReduceValuesTask<K,V,U>
5656	+	(map, this, b >>>= 1, rights, transformer, reducer)).fork();
5657	+	}
5658	+	U r = null, u;
5659	+	Object v;
5660	+	while ((v = advance()) != null) {
5661	+	if ((u = transformer.apply((V)v)) != null)
5662	+	r = (r == null) ? u : reducer.apply(r, u);
5663	+	}
5664	+	result = r;
5665	+	for (MapReduceValuesTask<K,V,U> t = this, s;;) {
5666	+	int c; BulkTask<K,V,?> par; U tr, sr;
5667	+	if ((c = t.pending) == 0) {
5668	+	for (s = t.rights; s != null; s = t.rights = s.nextRight) {
5669	+	if ((sr = s.result) != null)
5670	+	t.result = ((tr = t.result) == null) ? sr : reducer.apply(tr, sr);
5671	+	}
5672	+	if ((par = t.parent) == null ||
5673	+	!(par instanceof MapReduceValuesTask)) {
5674	+	t.quietlyComplete();
5675	+	break;
5676	+	}
5677	+	t = (MapReduceValuesTask<K,V,U>)par;
5678	+	}
5679	+	else if (t.casPending(c, c - 1))
5680	+	break;
5681	+	}
5682	+	} catch (Throwable ex) {
5683	+	return tryCompleteComputation(ex);
5684	+	}
5685	+	return false;
5686	+	}
5687	+	public final U getRawResult() { return result; }
5688	+	}
5689	+
5690	+	@SuppressWarnings("serial") static final class MapReduceEntriesTask<K,V,U>
5691	+	extends BulkTask<K,V,U> {
5692	+	final Fun<Map.Entry<K,V>, ? extends U> transformer;
5693	+	final BiFun<? super U, ? super U, ? extends U> reducer;
5694	+	U result;
5695	+	MapReduceEntriesTask<K,V,U> rights, nextRight;
5696	+	MapReduceEntriesTask
5697	+	(ConcurrentHashMap<K,V> m, BulkTask<K,V,?> p, int b,
5698	+	MapReduceEntriesTask<K,V,U> nextRight,
5699	+	Fun<Map.Entry<K,V>, ? extends U> transformer,
5700	+	BiFun<? super U, ? super U, ? extends U> reducer) {
5701	+	super(m, p, b); this.nextRight = nextRight;
5702	+	this.transformer = transformer;
5703	+	this.reducer = reducer;
5704	+	}
5705	+	@SuppressWarnings("unchecked") public final boolean exec() {
5706	+	final Fun<Map.Entry<K,V>, ? extends U> transformer =
5707	+	this.transformer;
5708	+	final BiFun<? super U, ? super U, ? extends U> reducer =
5709	+	this.reducer;
5710	+	if (transformer == null || reducer == null)
5711	+	return abortOnNullFunction();
5712	+	try {
5713	+	for (int c, b = batch(); b > 1 && baseIndex != baseLimit;) {
5714	+	do {} while (!casPending(c = pending, c+1));
5715	+	(rights = new MapReduceEntriesTask<K,V,U>
5716	+	(map, this, b >>>= 1, rights, transformer, reducer)).fork();
5717	+	}
5718	+	U r = null, u;
5719	+	Object v;
5720	+	while ((v = advance()) != null) {
5721	+	if ((u = transformer.apply(entryFor((K)nextKey, (V)v))) != null)
5722	+	r = (r == null) ? u : reducer.apply(r, u);
5723	+	}
5724	+	result = r;
5725	+	for (MapReduceEntriesTask<K,V,U> t = this, s;;) {
5726	+	int c; BulkTask<K,V,?> par; U tr, sr;
5727	+	if ((c = t.pending) == 0) {
5728	+	for (s = t.rights; s != null; s = t.rights = s.nextRight) {
5729	+	if ((sr = s.result) != null)
5730	+	t.result = ((tr = t.result) == null) ? sr : reducer.apply(tr, sr);
5731	+	}
5732	+	if ((par = t.parent) == null ||
5733	+	!(par instanceof MapReduceEntriesTask)) {
5734	+	t.quietlyComplete();
5735	+	break;
5736	+	}
5737	+	t = (MapReduceEntriesTask<K,V,U>)par;
5738	+	}
5739	+	else if (t.casPending(c, c - 1))
5740	+	break;
5741	+	}
5742	+	} catch (Throwable ex) {
5743	+	return tryCompleteComputation(ex);
5744	+	}
5745	+	return false;
5746	+	}
5747	+	public final U getRawResult() { return result; }
5748	+	}
5749	+
5750	+	@SuppressWarnings("serial") static final class MapReduceMappingsTask<K,V,U>
5751	+	extends BulkTask<K,V,U> {
5752	+	final BiFun<? super K, ? super V, ? extends U> transformer;
5753	+	final BiFun<? super U, ? super U, ? extends U> reducer;
5754	+	U result;
5755	+	MapReduceMappingsTask<K,V,U> rights, nextRight;
5756	+	MapReduceMappingsTask
5757	+	(ConcurrentHashMap<K,V> m, BulkTask<K,V,?> p, int b,
5758	+	MapReduceMappingsTask<K,V,U> nextRight,
5759	+	BiFun<? super K, ? super V, ? extends U> transformer,
5760	+	BiFun<? super U, ? super U, ? extends U> reducer) {
5761	+	super(m, p, b); this.nextRight = nextRight;
5762	+	this.transformer = transformer;
5763	+	this.reducer = reducer;
5764	+	}
5765	+	@SuppressWarnings("unchecked") public final boolean exec() {
5766	+	final BiFun<? super K, ? super V, ? extends U> transformer =
5767	+	this.transformer;
5768	+	final BiFun<? super U, ? super U, ? extends U> reducer =
5769	+	this.reducer;
5770	+	if (transformer == null || reducer == null)
5771	+	return abortOnNullFunction();
5772	+	try {
5773	+	for (int c, b = batch(); b > 1 && baseIndex != baseLimit;) {
5774	+	do {} while (!casPending(c = pending, c+1));
5775	+	(rights = new MapReduceMappingsTask<K,V,U>
5776	+	(map, this, b >>>= 1, rights, transformer, reducer)).fork();
5777	+	}
5778	+	U r = null, u;
5779	+	Object v;
5780	+	while ((v = advance()) != null) {
5781	+	if ((u = transformer.apply((K)nextKey, (V)v)) != null)
5782	+	r = (r == null) ? u : reducer.apply(r, u);
5783	+	}
5784	+	result = r;
5785	+	for (MapReduceMappingsTask<K,V,U> t = this, s;;) {
5786	+	int c; BulkTask<K,V,?> par; U tr, sr;
5787	+	if ((c = t.pending) == 0) {
5788	+	for (s = t.rights; s != null; s = t.rights = s.nextRight) {
5789	+	if ((sr = s.result) != null)
5790	+	t.result = ((tr = t.result) == null) ? sr : reducer.apply(tr, sr);
5791	+	}
5792	+	if ((par = t.parent) == null ||
5793	+	!(par instanceof MapReduceMappingsTask)) {
5794	+	t.quietlyComplete();
5795	+	break;
5796	+	}
5797	+	t = (MapReduceMappingsTask<K,V,U>)par;
5798	+	}
5799	+	else if (t.casPending(c, c - 1))
5800	+	break;
5801	+	}
5802	+	} catch (Throwable ex) {
5803	+	return tryCompleteComputation(ex);
5804	+	}
5805	+	return false;
5806	+	}
5807	+	public final U getRawResult() { return result; }
5808	+	}
5809	+
5810	+	@SuppressWarnings("serial") static final class MapReduceKeysToDoubleTask<K,V>
5811	+	extends BulkTask<K,V,Double> {
5812	+	final ObjectToDouble<? super K> transformer;
5813	+	final DoubleByDoubleToDouble reducer;
5814	+	final double basis;
5815	+	double result;
5816	+	MapReduceKeysToDoubleTask<K,V> rights, nextRight;
5817	+	MapReduceKeysToDoubleTask
5818	+	(ConcurrentHashMap<K,V> m, BulkTask<K,V,?> p, int b,
5819	+	MapReduceKeysToDoubleTask<K,V> nextRight,
5820	+	ObjectToDouble<? super K> transformer,
5821	+	double basis,
5822	+	DoubleByDoubleToDouble reducer) {
5823	+	super(m, p, b); this.nextRight = nextRight;
5824	+	this.transformer = transformer;
5825	+	this.basis = basis; this.reducer = reducer;
5826	+	}
5827	+	@SuppressWarnings("unchecked") public final boolean exec() {
5828	+	final ObjectToDouble<? super K> transformer =
5829	+	this.transformer;
5830	+	final DoubleByDoubleToDouble reducer = this.reducer;
5831	+	if (transformer == null || reducer == null)
5832	+	return abortOnNullFunction();
5833	+	try {
5834	+	final double id = this.basis;
5835	+	for (int c, b = batch(); b > 1 && baseIndex != baseLimit;) {
5836	+	do {} while (!casPending(c = pending, c+1));
5837	+	(rights = new MapReduceKeysToDoubleTask<K,V>
5838	+	(map, this, b >>>= 1, rights, transformer, id, reducer)).fork();
5839	+	}
5840	+	double r = id;
5841	+	while (advance() != null)
5842	+	r = reducer.apply(r, transformer.apply((K)nextKey));
5843	+	result = r;
5844	+	for (MapReduceKeysToDoubleTask<K,V> t = this, s;;) {
5845	+	int c; BulkTask<K,V,?> par;
5846	+	if ((c = t.pending) == 0) {
5847	+	for (s = t.rights; s != null; s = t.rights = s.nextRight) {
5848	+	t.result = reducer.apply(t.result, s.result);
5849	+	}
5850	+	if ((par = t.parent) == null ||
5851	+	!(par instanceof MapReduceKeysToDoubleTask)) {
5852	+	t.quietlyComplete();
5853	+	break;
5854	+	}
5855	+	t = (MapReduceKeysToDoubleTask<K,V>)par;
5856	+	}
5857	+	else if (t.casPending(c, c - 1))
5858	+	break;
5859	+	}
5860	+	} catch (Throwable ex) {
5861	+	return tryCompleteComputation(ex);
5862	+	}
5863	+	return false;
5864	+	}
5865	+	public final Double getRawResult() { return result; }
5866	+	}
5867	+
5868	+	@SuppressWarnings("serial") static final class MapReduceValuesToDoubleTask<K,V>
5869	+	extends BulkTask<K,V,Double> {
5870	+	final ObjectToDouble<? super V> transformer;
5871	+	final DoubleByDoubleToDouble reducer;
5872	+	final double basis;
5873	+	double result;
5874	+	MapReduceValuesToDoubleTask<K,V> rights, nextRight;
5875	+	MapReduceValuesToDoubleTask
5876	+	(ConcurrentHashMap<K,V> m, BulkTask<K,V,?> p, int b,
5877	+	MapReduceValuesToDoubleTask<K,V> nextRight,
5878	+	ObjectToDouble<? super V> transformer,
5879	+	double basis,
5880	+	DoubleByDoubleToDouble reducer) {
5881	+	super(m, p, b); this.nextRight = nextRight;
5882	+	this.transformer = transformer;
5883	+	this.basis = basis; this.reducer = reducer;
5884	+	}
5885	+	@SuppressWarnings("unchecked") public final boolean exec() {
5886	+	final ObjectToDouble<? super V> transformer =
5887	+	this.transformer;
5888	+	final DoubleByDoubleToDouble reducer = this.reducer;
5889	+	if (transformer == null || reducer == null)
5890	+	return abortOnNullFunction();
5891	+	try {
5892	+	final double id = this.basis;
5893	+	for (int c, b = batch(); b > 1 && baseIndex != baseLimit;) {
5894	+	do {} while (!casPending(c = pending, c+1));
5895	+	(rights = new MapReduceValuesToDoubleTask<K,V>
5896	+	(map, this, b >>>= 1, rights, transformer, id, reducer)).fork();
5897	+	}
5898	+	double r = id;
5899	+	Object v;
5900	+	while ((v = advance()) != null)
5901	+	r = reducer.apply(r, transformer.apply((V)v));
5902	+	result = r;
5903	+	for (MapReduceValuesToDoubleTask<K,V> t = this, s;;) {
5904	+	int c; BulkTask<K,V,?> par;
5905	+	if ((c = t.pending) == 0) {
5906	+	for (s = t.rights; s != null; s = t.rights = s.nextRight) {
5907	+	t.result = reducer.apply(t.result, s.result);
5908	+	}
5909	+	if ((par = t.parent) == null ||
5910	+	!(par instanceof MapReduceValuesToDoubleTask)) {
5911	+	t.quietlyComplete();
5912	+	break;
5913	+	}
5914	+	t = (MapReduceValuesToDoubleTask<K,V>)par;
5915	+	}
5916	+	else if (t.casPending(c, c - 1))
5917	+	break;
5918	+	}
5919	+	} catch (Throwable ex) {
5920	+	return tryCompleteComputation(ex);
5921	+	}
5922	+	return false;
5923	+	}
5924	+	public final Double getRawResult() { return result; }
5925	+	}
5926	+
5927	+	@SuppressWarnings("serial") static final class MapReduceEntriesToDoubleTask<K,V>
5928	+	extends BulkTask<K,V,Double> {
5929	+	final ObjectToDouble<Map.Entry<K,V>> transformer;
5930	+	final DoubleByDoubleToDouble reducer;
5931	+	final double basis;
5932	+	double result;
5933	+	MapReduceEntriesToDoubleTask<K,V> rights, nextRight;
5934	+	MapReduceEntriesToDoubleTask
5935	+	(ConcurrentHashMap<K,V> m, BulkTask<K,V,?> p, int b,
5936	+	MapReduceEntriesToDoubleTask<K,V> nextRight,
5937	+	ObjectToDouble<Map.Entry<K,V>> transformer,
5938	+	double basis,
5939	+	DoubleByDoubleToDouble reducer) {
5940	+	super(m, p, b); this.nextRight = nextRight;
5941	+	this.transformer = transformer;
5942	+	this.basis = basis; this.reducer = reducer;
5943	+	}
5944	+	@SuppressWarnings("unchecked") public final boolean exec() {
5945	+	final ObjectToDouble<Map.Entry<K,V>> transformer =
5946	+	this.transformer;
5947	+	final DoubleByDoubleToDouble reducer = this.reducer;
5948	+	if (transformer == null || reducer == null)
5949	+	return abortOnNullFunction();
5950	+	try {
5951	+	final double id = this.basis;
5952	+	for (int c, b = batch(); b > 1 && baseIndex != baseLimit;) {
5953	+	do {} while (!casPending(c = pending, c+1));
5954	+	(rights = new MapReduceEntriesToDoubleTask<K,V>
5955	+	(map, this, b >>>= 1, rights, transformer, id, reducer)).fork();
5956	+	}
5957	+	double r = id;
5958	+	Object v;
5959	+	while ((v = advance()) != null)
5960	+	r = reducer.apply(r, transformer.apply(entryFor((K)nextKey, (V)v)));
5961	+	result = r;
5962	+	for (MapReduceEntriesToDoubleTask<K,V> t = this, s;;) {
5963	+	int c; BulkTask<K,V,?> par;
5964	+	if ((c = t.pending) == 0) {
5965	+	for (s = t.rights; s != null; s = t.rights = s.nextRight) {
5966	+	t.result = reducer.apply(t.result, s.result);
5967	+	}
5968	+	if ((par = t.parent) == null ||
5969	+	!(par instanceof MapReduceEntriesToDoubleTask)) {
5970	+	t.quietlyComplete();
5971	+	break;
5972	+	}
5973	+	t = (MapReduceEntriesToDoubleTask<K,V>)par;
5974	+	}
5975	+	else if (t.casPending(c, c - 1))
5976	+	break;
5977	+	}
5978	+	} catch (Throwable ex) {
5979	+	return tryCompleteComputation(ex);
5980	+	}
5981	+	return false;
5982	+	}
5983	+	public final Double getRawResult() { return result; }
5984	+	}
5985	+
5986	+	@SuppressWarnings("serial") static final class MapReduceMappingsToDoubleTask<K,V>
5987	+	extends BulkTask<K,V,Double> {
5988	+	final ObjectByObjectToDouble<? super K, ? super V> transformer;
5989	+	final DoubleByDoubleToDouble reducer;
5990	+	final double basis;
5991	+	double result;
5992	+	MapReduceMappingsToDoubleTask<K,V> rights, nextRight;
5993	+	MapReduceMappingsToDoubleTask
5994	+	(ConcurrentHashMap<K,V> m, BulkTask<K,V,?> p, int b,
5995	+	MapReduceMappingsToDoubleTask<K,V> nextRight,
5996	+	ObjectByObjectToDouble<? super K, ? super V> transformer,
5997	+	double basis,
5998	+	DoubleByDoubleToDouble reducer) {
5999	+	super(m, p, b); this.nextRight = nextRight;
6000	+	this.transformer = transformer;
6001	+	this.basis = basis; this.reducer = reducer;
6002	+	}
6003	+	@SuppressWarnings("unchecked") public final boolean exec() {
6004	+	final ObjectByObjectToDouble<? super K, ? super V> transformer =
6005	+	this.transformer;
6006	+	final DoubleByDoubleToDouble reducer = this.reducer;
6007	+	if (transformer == null || reducer == null)
6008	+	return abortOnNullFunction();
6009	+	try {
6010	+	final double id = this.basis;
6011	+	for (int c, b = batch(); b > 1 && baseIndex != baseLimit;) {
6012	+	do {} while (!casPending(c = pending, c+1));
6013	+	(rights = new MapReduceMappingsToDoubleTask<K,V>
6014	+	(map, this, b >>>= 1, rights, transformer, id, reducer)).fork();
6015	+	}
6016	+	double r = id;
6017	+	Object v;
6018	+	while ((v = advance()) != null)
6019	+	r = reducer.apply(r, transformer.apply((K)nextKey, (V)v));
6020	+	result = r;
6021	+	for (MapReduceMappingsToDoubleTask<K,V> t = this, s;;) {
6022	+	int c; BulkTask<K,V,?> par;
6023	+	if ((c = t.pending) == 0) {
6024	+	for (s = t.rights; s != null; s = t.rights = s.nextRight) {
6025	+	t.result = reducer.apply(t.result, s.result);
6026	+	}
6027	+	if ((par = t.parent) == null ||
6028	+	!(par instanceof MapReduceMappingsToDoubleTask)) {
6029	+	t.quietlyComplete();
6030	+	break;
6031	+	}
6032	+	t = (MapReduceMappingsToDoubleTask<K,V>)par;
6033	+	}
6034	+	else if (t.casPending(c, c - 1))
6035	+	break;
6036	+	}
6037	+	} catch (Throwable ex) {
6038	+	return tryCompleteComputation(ex);
6039	+	}
6040	+	return false;
6041	+	}
6042	+	public final Double getRawResult() { return result; }
6043	+	}
6044	+
6045	+	@SuppressWarnings("serial") static final class MapReduceKeysToLongTask<K,V>
6046	+	extends BulkTask<K,V,Long> {
6047	+	final ObjectToLong<? super K> transformer;
6048	+	final LongByLongToLong reducer;
6049	+	final long basis;
6050	+	long result;
6051	+	MapReduceKeysToLongTask<K,V> rights, nextRight;
6052	+	MapReduceKeysToLongTask
6053	+	(ConcurrentHashMap<K,V> m, BulkTask<K,V,?> p, int b,
6054	+	MapReduceKeysToLongTask<K,V> nextRight,
6055	+	ObjectToLong<? super K> transformer,
6056	+	long basis,
6057	+	LongByLongToLong reducer) {
6058	+	super(m, p, b); this.nextRight = nextRight;
6059	+	this.transformer = transformer;
6060	+	this.basis = basis; this.reducer = reducer;
6061	+	}
6062	+	@SuppressWarnings("unchecked") public final boolean exec() {
6063	+	final ObjectToLong<? super K> transformer =
6064	+	this.transformer;
6065	+	final LongByLongToLong reducer = this.reducer;
6066	+	if (transformer == null || reducer == null)
6067	+	return abortOnNullFunction();
6068	+	try {
6069	+	final long id = this.basis;
6070	+	for (int c, b = batch(); b > 1 && baseIndex != baseLimit;) {
6071	+	do {} while (!casPending(c = pending, c+1));
6072	+	(rights = new MapReduceKeysToLongTask<K,V>
6073	+	(map, this, b >>>= 1, rights, transformer, id, reducer)).fork();
6074	+	}
6075	+	long r = id;
6076	+	while (advance() != null)
6077	+	r = reducer.apply(r, transformer.apply((K)nextKey));
6078	+	result = r;
6079	+	for (MapReduceKeysToLongTask<K,V> t = this, s;;) {
6080	+	int c; BulkTask<K,V,?> par;
6081	+	if ((c = t.pending) == 0) {
6082	+	for (s = t.rights; s != null; s = t.rights = s.nextRight) {
6083	+	t.result = reducer.apply(t.result, s.result);
6084	+	}
6085	+	if ((par = t.parent) == null ||
6086	+	!(par instanceof MapReduceKeysToLongTask)) {
6087	+	t.quietlyComplete();
6088	+	break;
6089	+	}
6090	+	t = (MapReduceKeysToLongTask<K,V>)par;
6091	+	}
6092	+	else if (t.casPending(c, c - 1))
6093	+	break;
6094	+	}
6095	+	} catch (Throwable ex) {
6096	+	return tryCompleteComputation(ex);
6097	+	}
6098	+	return false;
6099	+	}
6100	+	public final Long getRawResult() { return result; }
6101	+	}
6102	+
6103	+	@SuppressWarnings("serial") static final class MapReduceValuesToLongTask<K,V>
6104	+	extends BulkTask<K,V,Long> {
6105	+	final ObjectToLong<? super V> transformer;
6106	+	final LongByLongToLong reducer;
6107	+	final long basis;
6108	+	long result;
6109	+	MapReduceValuesToLongTask<K,V> rights, nextRight;
6110	+	MapReduceValuesToLongTask
6111	+	(ConcurrentHashMap<K,V> m, BulkTask<K,V,?> p, int b,
6112	+	MapReduceValuesToLongTask<K,V> nextRight,
6113	+	ObjectToLong<? super V> transformer,
6114	+	long basis,
6115	+	LongByLongToLong reducer) {
6116	+	super(m, p, b); this.nextRight = nextRight;
6117	+	this.transformer = transformer;
6118	+	this.basis = basis; this.reducer = reducer;
6119	+	}
6120	+	@SuppressWarnings("unchecked") public final boolean exec() {
6121	+	final ObjectToLong<? super V> transformer =
6122	+	this.transformer;
6123	+	final LongByLongToLong reducer = this.reducer;
6124	+	if (transformer == null || reducer == null)
6125	+	return abortOnNullFunction();
6126	+	try {
6127	+	final long id = this.basis;
6128	+	for (int c, b = batch(); b > 1 && baseIndex != baseLimit;) {
6129	+	do {} while (!casPending(c = pending, c+1));
6130	+	(rights = new MapReduceValuesToLongTask<K,V>
6131	+	(map, this, b >>>= 1, rights, transformer, id, reducer)).fork();
6132	+	}
6133	+	long r = id;
6134	+	Object v;
6135	+	while ((v = advance()) != null)
6136	+	r = reducer.apply(r, transformer.apply((V)v));
6137	+	result = r;
6138	+	for (MapReduceValuesToLongTask<K,V> t = this, s;;) {
6139	+	int c; BulkTask<K,V,?> par;
6140	+	if ((c = t.pending) == 0) {
6141	+	for (s = t.rights; s != null; s = t.rights = s.nextRight) {
6142	+	t.result = reducer.apply(t.result, s.result);
6143	+	}
6144	+	if ((par = t.parent) == null ||
6145	+	!(par instanceof MapReduceValuesToLongTask)) {
6146	+	t.quietlyComplete();
6147	+	break;
6148	+	}
6149	+	t = (MapReduceValuesToLongTask<K,V>)par;
6150	+	}
6151	+	else if (t.casPending(c, c - 1))
6152	+	break;
6153	+	}
6154	+	} catch (Throwable ex) {
6155	+	return tryCompleteComputation(ex);
6156	+	}
6157	+	return false;
6158	+	}
6159	+	public final Long getRawResult() { return result; }
6160	+	}
6161	+
6162	+	@SuppressWarnings("serial") static final class MapReduceEntriesToLongTask<K,V>
6163	+	extends BulkTask<K,V,Long> {
6164	+	final ObjectToLong<Map.Entry<K,V>> transformer;
6165	+	final LongByLongToLong reducer;
6166	+	final long basis;
6167	+	long result;
6168	+	MapReduceEntriesToLongTask<K,V> rights, nextRight;
6169	+	MapReduceEntriesToLongTask
6170	+	(ConcurrentHashMap<K,V> m, BulkTask<K,V,?> p, int b,
6171	+	MapReduceEntriesToLongTask<K,V> nextRight,
6172	+	ObjectToLong<Map.Entry<K,V>> transformer,
6173	+	long basis,
6174	+	LongByLongToLong reducer) {
6175	+	super(m, p, b); this.nextRight = nextRight;
6176	+	this.transformer = transformer;
6177	+	this.basis = basis; this.reducer = reducer;
6178	+	}
6179	+	@SuppressWarnings("unchecked") public final boolean exec() {
6180	+	final ObjectToLong<Map.Entry<K,V>> transformer =
6181	+	this.transformer;
6182	+	final LongByLongToLong reducer = this.reducer;
6183	+	if (transformer == null || reducer == null)
6184	+	return abortOnNullFunction();
6185	+	try {
6186	+	final long id = this.basis;
6187	+	for (int c, b = batch(); b > 1 && baseIndex != baseLimit;) {
6188	+	do {} while (!casPending(c = pending, c+1));
6189	+	(rights = new MapReduceEntriesToLongTask<K,V>
6190	+	(map, this, b >>>= 1, rights, transformer, id, reducer)).fork();
6191	+	}
6192	+	long r = id;
6193	+	Object v;
6194	+	while ((v = advance()) != null)
6195	+	r = reducer.apply(r, transformer.apply(entryFor((K)nextKey, (V)v)));
6196	+	result = r;
6197	+	for (MapReduceEntriesToLongTask<K,V> t = this, s;;) {
6198	+	int c; BulkTask<K,V,?> par;
6199	+	if ((c = t.pending) == 0) {
6200	+	for (s = t.rights; s != null; s = t.rights = s.nextRight) {
6201	+	t.result = reducer.apply(t.result, s.result);
6202	+	}
6203	+	if ((par = t.parent) == null ||
6204	+	!(par instanceof MapReduceEntriesToLongTask)) {
6205	+	t.quietlyComplete();
6206	+	break;
6207	+	}
6208	+	t = (MapReduceEntriesToLongTask<K,V>)par;
6209	+	}
6210	+	else if (t.casPending(c, c - 1))
6211	+	break;
6212	+	}
6213	+	} catch (Throwable ex) {
6214	+	return tryCompleteComputation(ex);
6215	+	}
6216	+	return false;
6217	+	}
6218	+	public final Long getRawResult() { return result; }
6219	+	}
6220	+
6221	+	@SuppressWarnings("serial") static final class MapReduceMappingsToLongTask<K,V>
6222	+	extends BulkTask<K,V,Long> {
6223	+	final ObjectByObjectToLong<? super K, ? super V> transformer;
6224	+	final LongByLongToLong reducer;
6225	+	final long basis;
6226	+	long result;
6227	+	MapReduceMappingsToLongTask<K,V> rights, nextRight;
6228	+	MapReduceMappingsToLongTask
6229	+	(ConcurrentHashMap<K,V> m, BulkTask<K,V,?> p, int b,
6230	+	MapReduceMappingsToLongTask<K,V> nextRight,
6231	+	ObjectByObjectToLong<? super K, ? super V> transformer,
6232	+	long basis,
6233	+	LongByLongToLong reducer) {
6234	+	super(m, p, b); this.nextRight = nextRight;
6235	+	this.transformer = transformer;
6236	+	this.basis = basis; this.reducer = reducer;
6237	+	}
6238	+	@SuppressWarnings("unchecked") public final boolean exec() {
6239	+	final ObjectByObjectToLong<? super K, ? super V> transformer =
6240	+	this.transformer;
6241	+	final LongByLongToLong reducer = this.reducer;
6242	+	if (transformer == null || reducer == null)
6243	+	return abortOnNullFunction();
6244	+	try {
6245	+	final long id = this.basis;
6246	+	for (int c, b = batch(); b > 1 && baseIndex != baseLimit;) {
6247	+	do {} while (!casPending(c = pending, c+1));
6248	+	(rights = new MapReduceMappingsToLongTask<K,V>
6249	+	(map, this, b >>>= 1, rights, transformer, id, reducer)).fork();
6250	+	}
6251	+	long r = id;
6252	+	Object v;
6253	+	while ((v = advance()) != null)
6254	+	r = reducer.apply(r, transformer.apply((K)nextKey, (V)v));
6255	+	result = r;
6256	+	for (MapReduceMappingsToLongTask<K,V> t = this, s;;) {
6257	+	int c; BulkTask<K,V,?> par;
6258	+	if ((c = t.pending) == 0) {
6259	+	for (s = t.rights; s != null; s = t.rights = s.nextRight) {
6260	+	t.result = reducer.apply(t.result, s.result);
6261	+	}
6262	+	if ((par = t.parent) == null ||
6263	+	!(par instanceof MapReduceMappingsToLongTask)) {
6264	+	t.quietlyComplete();
6265	+	break;
6266	+	}
6267	+	t = (MapReduceMappingsToLongTask<K,V>)par;
6268	+	}
6269	+	else if (t.casPending(c, c - 1))
6270	+	break;
6271	+	}
6272	+	} catch (Throwable ex) {
6273	+	return tryCompleteComputation(ex);
6274	+	}
6275	+	return false;
6276	+	}
6277	+	public final Long getRawResult() { return result; }
6278	+	}
6279	+
6280	+	@SuppressWarnings("serial") static final class MapReduceKeysToIntTask<K,V>
6281	+	extends BulkTask<K,V,Integer> {
6282	+	final ObjectToInt<? super K> transformer;
6283	+	final IntByIntToInt reducer;
6284	+	final int basis;
6285	+	int result;
6286	+	MapReduceKeysToIntTask<K,V> rights, nextRight;
6287	+	MapReduceKeysToIntTask
6288	+	(ConcurrentHashMap<K,V> m, BulkTask<K,V,?> p, int b,
6289	+	MapReduceKeysToIntTask<K,V> nextRight,
6290	+	ObjectToInt<? super K> transformer,
6291	+	int basis,
6292	+	IntByIntToInt reducer) {
6293	+	super(m, p, b); this.nextRight = nextRight;
6294	+	this.transformer = transformer;
6295	+	this.basis = basis; this.reducer = reducer;
6296	+	}
6297	+	@SuppressWarnings("unchecked") public final boolean exec() {
6298	+	final ObjectToInt<? super K> transformer =
6299	+	this.transformer;
6300	+	final IntByIntToInt reducer = this.reducer;
6301	+	if (transformer == null || reducer == null)
6302	+	return abortOnNullFunction();
6303	+	try {
6304	+	final int id = this.basis;
6305	+	for (int c, b = batch(); b > 1 && baseIndex != baseLimit;) {
6306	+	do {} while (!casPending(c = pending, c+1));
6307	+	(rights = new MapReduceKeysToIntTask<K,V>
6308	+	(map, this, b >>>= 1, rights, transformer, id, reducer)).fork();
6309	+	}
6310	+	int r = id;
6311	+	while (advance() != null)
6312	+	r = reducer.apply(r, transformer.apply((K)nextKey));
6313	+	result = r;
6314	+	for (MapReduceKeysToIntTask<K,V> t = this, s;;) {
6315	+	int c; BulkTask<K,V,?> par;
6316	+	if ((c = t.pending) == 0) {
6317	+	for (s = t.rights; s != null; s = t.rights = s.nextRight) {
6318	+	t.result = reducer.apply(t.result, s.result);
6319	+	}
6320	+	if ((par = t.parent) == null ||
6321	+	!(par instanceof MapReduceKeysToIntTask)) {
6322	+	t.quietlyComplete();
6323	+	break;
6324	+	}
6325	+	t = (MapReduceKeysToIntTask<K,V>)par;
6326	+	}
6327	+	else if (t.casPending(c, c - 1))
6328	+	break;
6329	+	}
6330	+	} catch (Throwable ex) {
6331	+	return tryCompleteComputation(ex);
6332	+	}
6333	+	return false;
6334	+	}
6335	+	public final Integer getRawResult() { return result; }
6336	+	}
6337	+
6338	+	@SuppressWarnings("serial") static final class MapReduceValuesToIntTask<K,V>
6339	+	extends BulkTask<K,V,Integer> {
6340	+	final ObjectToInt<? super V> transformer;
6341	+	final IntByIntToInt reducer;
6342	+	final int basis;
6343	+	int result;
6344	+	MapReduceValuesToIntTask<K,V> rights, nextRight;
6345	+	MapReduceValuesToIntTask
6346	+	(ConcurrentHashMap<K,V> m, BulkTask<K,V,?> p, int b,
6347	+	MapReduceValuesToIntTask<K,V> nextRight,
6348	+	ObjectToInt<? super V> transformer,
6349	+	int basis,
6350	+	IntByIntToInt reducer) {
6351	+	super(m, p, b); this.nextRight = nextRight;
6352	+	this.transformer = transformer;
6353	+	this.basis = basis; this.reducer = reducer;
6354	+	}
6355	+	@SuppressWarnings("unchecked") public final boolean exec() {
6356	+	final ObjectToInt<? super V> transformer =
6357	+	this.transformer;
6358	+	final IntByIntToInt reducer = this.reducer;
6359	+	if (transformer == null || reducer == null)
6360	+	return abortOnNullFunction();
6361	+	try {
6362	+	final int id = this.basis;
6363	+	for (int c, b = batch(); b > 1 && baseIndex != baseLimit;) {
6364	+	do {} while (!casPending(c = pending, c+1));
6365	+	(rights = new MapReduceValuesToIntTask<K,V>
6366	+	(map, this, b >>>= 1, rights, transformer, id, reducer)).fork();
6367	+	}
6368	+	int r = id;
6369	+	Object v;
6370	+	while ((v = advance()) != null)
6371	+	r = reducer.apply(r, transformer.apply((V)v));
6372	+	result = r;
6373	+	for (MapReduceValuesToIntTask<K,V> t = this, s;;) {
6374	+	int c; BulkTask<K,V,?> par;
6375	+	if ((c = t.pending) == 0) {
6376	+	for (s = t.rights; s != null; s = t.rights = s.nextRight) {
6377	+	t.result = reducer.apply(t.result, s.result);
6378	+	}
6379	+	if ((par = t.parent) == null ||
6380	+	!(par instanceof MapReduceValuesToIntTask)) {
6381	+	t.quietlyComplete();
6382	+	break;
6383	+	}
6384	+	t = (MapReduceValuesToIntTask<K,V>)par;
6385	+	}
6386	+	else if (t.casPending(c, c - 1))
6387	+	break;
6388	+	}
6389	+	} catch (Throwable ex) {
6390	+	return tryCompleteComputation(ex);
6391	+	}
6392	+	return false;
6393	+	}
6394	+	public final Integer getRawResult() { return result; }
6395	+	}
6396	+
6397	+	@SuppressWarnings("serial") static final class MapReduceEntriesToIntTask<K,V>
6398	+	extends BulkTask<K,V,Integer> {
6399	+	final ObjectToInt<Map.Entry<K,V>> transformer;
6400	+	final IntByIntToInt reducer;
6401	+	final int basis;
6402	+	int result;
6403	+	MapReduceEntriesToIntTask<K,V> rights, nextRight;
6404	+	MapReduceEntriesToIntTask
6405	+	(ConcurrentHashMap<K,V> m, BulkTask<K,V,?> p, int b,
6406	+	MapReduceEntriesToIntTask<K,V> nextRight,
6407	+	ObjectToInt<Map.Entry<K,V>> transformer,
6408	+	int basis,
6409	+	IntByIntToInt reducer) {
6410	+	super(m, p, b); this.nextRight = nextRight;
6411	+	this.transformer = transformer;
6412	+	this.basis = basis; this.reducer = reducer;
6413	+	}
6414	+	@SuppressWarnings("unchecked") public final boolean exec() {
6415	+	final ObjectToInt<Map.Entry<K,V>> transformer =
6416	+	this.transformer;
6417	+	final IntByIntToInt reducer = this.reducer;
6418	+	if (transformer == null || reducer == null)
6419	+	return abortOnNullFunction();
6420	+	try {
6421	+	final int id = this.basis;
6422	+	for (int c, b = batch(); b > 1 && baseIndex != baseLimit;) {
6423	+	do {} while (!casPending(c = pending, c+1));
6424	+	(rights = new MapReduceEntriesToIntTask<K,V>
6425	+	(map, this, b >>>= 1, rights, transformer, id, reducer)).fork();
6426	+	}
6427	+	int r = id;
6428	+	Object v;
6429	+	while ((v = advance()) != null)
6430	+	r = reducer.apply(r, transformer.apply(entryFor((K)nextKey, (V)v)));
6431	+	result = r;
6432	+	for (MapReduceEntriesToIntTask<K,V> t = this, s;;) {
6433	+	int c; BulkTask<K,V,?> par;
6434	+	if ((c = t.pending) == 0) {
6435	+	for (s = t.rights; s != null; s = t.rights = s.nextRight) {
6436	+	t.result = reducer.apply(t.result, s.result);
6437	+	}
6438	+	if ((par = t.parent) == null ||
6439	+	!(par instanceof MapReduceEntriesToIntTask)) {
6440	+	t.quietlyComplete();
6441	+	break;
6442	+	}
6443	+	t = (MapReduceEntriesToIntTask<K,V>)par;
6444	+	}
6445	+	else if (t.casPending(c, c - 1))
6446	+	break;
6447	+	}
6448	+	} catch (Throwable ex) {
6449	+	return tryCompleteComputation(ex);
6450	+	}
6451	+	return false;
6452	+	}
6453	+	public final Integer getRawResult() { return result; }
6454	+	}
6455	+
6456	+	@SuppressWarnings("serial") static final class MapReduceMappingsToIntTask<K,V>
6457	+	extends BulkTask<K,V,Integer> {
6458	+	final ObjectByObjectToInt<? super K, ? super V> transformer;
6459	+	final IntByIntToInt reducer;
6460	+	final int basis;
6461	+	int result;
6462	+	MapReduceMappingsToIntTask<K,V> rights, nextRight;
6463	+	MapReduceMappingsToIntTask
6464	+	(ConcurrentHashMap<K,V> m, BulkTask<K,V,?> p, int b,
6465	+	MapReduceMappingsToIntTask<K,V> rights,
6466	+	ObjectByObjectToInt<? super K, ? super V> transformer,
6467	+	int basis,
6468	+	IntByIntToInt reducer) {
6469	+	super(m, p, b); this.nextRight = nextRight;
6470	+	this.transformer = transformer;
6471	+	this.basis = basis; this.reducer = reducer;
6472	+	}
6473	+	@SuppressWarnings("unchecked") public final boolean exec() {
6474	+	final ObjectByObjectToInt<? super K, ? super V> transformer =
6475	+	this.transformer;
6476	+	final IntByIntToInt reducer = this.reducer;
6477	+	if (transformer == null || reducer == null)
6478	+	return abortOnNullFunction();
6479	+	try {
6480	+	final int id = this.basis;
6481	+	for (int c, b = batch(); b > 1 && baseIndex != baseLimit;) {
6482	+	do {} while (!casPending(c = pending, c+1));
6483	+	(rights = new MapReduceMappingsToIntTask<K,V>
6484	+	(map, this, b >>>= 1, rights, transformer, id, reducer)).fork();
6485	+	}
6486	+	int r = id;
6487	+	Object v;
6488	+	while ((v = advance()) != null)
6489	+	r = reducer.apply(r, transformer.apply((K)nextKey, (V)v));
6490	+	result = r;
6491	+	for (MapReduceMappingsToIntTask<K,V> t = this, s;;) {
6492	+	int c; BulkTask<K,V,?> par;
6493	+	if ((c = t.pending) == 0) {
6494	+	for (s = t.rights; s != null; s = t.rights = s.nextRight) {
6495	+	t.result = reducer.apply(t.result, s.result);
6496	+	}
6497	+	if ((par = t.parent) == null ||
6498	+	!(par instanceof MapReduceMappingsToIntTask)) {
6499	+	t.quietlyComplete();
6500	+	break;
6501	+	}
6502	+	t = (MapReduceMappingsToIntTask<K,V>)par;
6503	+	}
6504	+	else if (t.casPending(c, c - 1))
6505	+	break;
6506	+	}
6507	+	} catch (Throwable ex) {
6508	+	return tryCompleteComputation(ex);
6509	+	}
6510	+	return false;
6511	+	}
6512	+	public final Integer getRawResult() { return result; }
6513	+	}
6514	+
6515	+
6516	+	// Unsafe mechanics
6517	+	private static final sun.misc.Unsafe UNSAFE;
6518	+	private static final long counterOffset;
6519	+	private static final long sizeCtlOffset;
6520	+	private static final long ABASE;
6521	+	private static final int ASHIFT;
6522	+
6523	+	static {
6524	+	int ss;
6525	+	try {
6526	+	UNSAFE = sun.misc.Unsafe.getUnsafe();
6527	+	Class<?> k = ConcurrentHashMap.class;
6528	+	counterOffset = UNSAFE.objectFieldOffset
6529	+	(k.getDeclaredField("counter"));
6530	+	sizeCtlOffset = UNSAFE.objectFieldOffset
6531	+	(k.getDeclaredField("sizeCtl"));
6532	+	Class<?> sc = Node[].class;
6533	+	ABASE = UNSAFE.arrayBaseOffset(sc);
6534	+	ss = UNSAFE.arrayIndexScale(sc);
6535	+	} catch (Exception e) {
6536	+	throw new Error(e);
6537	+	}
6538	+	if ((ss & (ss-1)) != 0)
6539	+	throw new Error("data type scale not a power of two");
6540	+	ASHIFT = 31 - Integer.numberOfLeadingZeros(ss);
6541	+	}
6542		}

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