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Comparing jsr166/src/main/java/util/concurrent/ConcurrentHashMap.java (file contents):
Revision 1.83 by jsr166, Mon Aug 22 03:42:10 2005 UTC vs.
Revision 1.194 by dl, Wed Mar 13 12:39:01 2013 UTC

#	Line 1 | Line 1
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.ForkJoinPool;
9	>	import java.util.concurrent.CountedCompleter;
10	>	import java.util.function.*;
11	>	import java.util.Spliterator;
12	>	import java.util.stream.Stream;
13	>	import java.util.stream.Streams;
14	>
15	>	import java.util.Comparator;
16	>	import java.util.Arrays;
17	>	import java.util.Map;
18	>	import java.util.Set;
19	>	import java.util.Collection;
20	>	import java.util.AbstractMap;
21	>	import java.util.AbstractSet;
22	>	import java.util.AbstractCollection;
23	>	import java.util.Hashtable;
24	>	import java.util.HashMap;
25	>	import java.util.Iterator;
26	>	import java.util.Enumeration;
27	>	import java.util.ConcurrentModificationException;
28	>	import java.util.NoSuchElementException;
29	>	import java.util.concurrent.ConcurrentMap;
30	>	import java.util.concurrent.locks.AbstractQueuedSynchronizer;
31	>	import java.util.concurrent.atomic.AtomicInteger;
32	>	import java.util.concurrent.atomic.AtomicReference;
33		import java.io.Serializable;
11	–	import java.io.IOException;
12	–	import java.io.ObjectInputStream;
13	–	import java.io.ObjectOutputStream;
34
35		/**
36		* A hash table supporting full concurrency of retrievals and
37	<	* adjustable expected concurrency for updates. This class obeys the
37	>	* high expected concurrency for updates. This class obeys the
38		* same functional specification as {@link java.util.Hashtable}, and
39		* includes versions of methods corresponding to each method of
40	<	* <tt>Hashtable</tt>. However, even though all operations are
40	>	* {@code Hashtable}. However, even though all operations are
41		* thread-safe, retrieval operations do <em>not</em> entail locking,
42		* and there is <em>not</em> any support for locking the entire table
43		* in a way that prevents all access.  This class is fully
44	<	* interoperable with <tt>Hashtable</tt> in programs that rely on its
44	>	* interoperable with {@code Hashtable} in programs that rely on its
45		* thread safety but not on its synchronization details.
46		*
47	<	* <p> Retrieval operations (including <tt>get</tt>) generally do not
48	<	* block, so may overlap with update operations (including
49	<	* <tt>put</tt> and <tt>remove</tt>). Retrievals reflect the results
50	<	* of the most recently <em>completed</em> update operations holding
51	<	* upon their onset.  For aggregate operations such as <tt>putAll</tt>
52	<	* and <tt>clear</tt>, concurrent retrievals may reflect insertion or
53	<	* removal of only some entries.  Similarly, Iterators and
54	<	* Enumerations return elements reflecting the state of the hash table
55	<	* at some point at or since the creation of the iterator/enumeration.
56	<	* They do <em>not</em> throw {@link ConcurrentModificationException}.
57	<	* However, iterators are designed to be used by only one thread at a time.
58	<	*
59	<	* <p> The allowed concurrency among update operations is guided by
60	<	* the optional <tt>concurrencyLevel</tt> constructor argument
61	<	* (default <tt>16</tt>), which is used as a hint for internal sizing.  The
62	<	* table is internally partitioned to try to permit the indicated
63	<	* number of concurrent updates without contention. Because placement
64	<	* in hash tables is essentially random, the actual concurrency will
65	<	* vary.  Ideally, you should choose a value to accommodate as many
66	<	* threads as will ever concurrently modify the table. Using a
67	<	* significantly higher value than you need can waste space and time,
68	<	* and a significantly lower value can lead to thread contention. But
69	<	* overestimates and underestimates within an order of magnitude do
70	<	* not usually have much noticeable impact. A value of one is
71	<	* appropriate when it is known that only one thread will modify and
72	<	* all others will only read. Also, resizing this or any other kind of
73	<	* hash table is a relatively slow operation, so, when possible, it is
74	<	* a good idea to provide estimates of expected table sizes in
75	<	* constructors.
47	>	* <p>Retrieval operations (including {@code get}) generally do not
48	>	* block, so may overlap with update operations (including {@code put}
49	>	* and {@code remove}). Retrievals reflect the results of the most
50	>	* recently <em>completed</em> update operations holding upon their
51	>	* onset. (More formally, an update operation for a given key bears a
52	>	* <em>happens-before</em> relation with any (non-null) retrieval for
53	>	* that key reporting the updated value.)  For aggregate operations
54	>	* such as {@code putAll} and {@code clear}, concurrent retrievals may
55	>	* reflect insertion or removal of only some entries.  Similarly,
56	>	* Iterators and Enumerations return elements reflecting the state of
57	>	* the hash table at some point at or since the creation of the
58	>	* iterator/enumeration.  They do <em>not</em> throw {@link
59	>	* ConcurrentModificationException}.  However, iterators are designed
60	>	* to be used by only one thread at a time.  Bear in mind that the
61	>	* results of aggregate status methods including {@code size}, {@code
62	>	* isEmpty}, and {@code containsValue} are typically useful only when
63	>	* a map is not undergoing concurrent updates in other threads.
64	>	* Otherwise the results of these methods reflect transient states
65	>	* that may be adequate for monitoring or estimation purposes, but not
66	>	* for program control.
67	>	*
68	>	* <p>The table is dynamically expanded when there are too many
69	>	* collisions (i.e., keys that have distinct hash codes but fall into
70	>	* the same slot modulo the table size), with the expected average
71	>	* effect of maintaining roughly two bins per mapping (corresponding
72	>	* to a 0.75 load factor threshold for resizing). There may be much
73	>	* variance around this average as mappings are added and removed, but
74	>	* overall, this maintains a commonly accepted time/space tradeoff for
75	>	* hash tables.  However, resizing this or any other kind of hash
76	>	* table may be a relatively slow operation. When possible, it is a
77	>	* good idea to provide a size estimate as an optional {@code
78	>	* initialCapacity} constructor argument. An additional optional
79	>	* {@code loadFactor} constructor argument provides a further means of
80	>	* customizing initial table capacity by specifying the table density
81	>	* to be used in calculating the amount of space to allocate for the
82	>	* given number of elements.  Also, for compatibility with previous
83	>	* versions of this class, constructors may optionally specify an
84	>	* expected {@code concurrencyLevel} as an additional hint for
85	>	* internal sizing.  Note that using many keys with exactly the same
86	>	* {@code hashCode()} is a sure way to slow down performance of any
87	>	* hash table.
88	>	*
89	>	* <p>A {@link Set} projection of a ConcurrentHashMap may be created
90	>	* (using {@link #newKeySet()} or {@link #newKeySet(int)}), or viewed
91	>	* (using {@link #keySet(Object)} when only keys are of interest, and the
92	>	* mapped values are (perhaps transiently) not used or all take the
93	>	* same mapping value.
94	>	*
95	>	* <p>A ConcurrentHashMap can be used as scalable frequency map (a
96	>	* form of histogram or multiset) by using {@link
97	>	* java.util.concurrent.atomic.LongAdder} values and initializing via
98	>	* {@link #computeIfAbsent computeIfAbsent}. For example, to add a count
99	>	* to a {@code ConcurrentHashMap<String,LongAdder> freqs}, you can use
100	>	* {@code freqs.computeIfAbsent(k -> new LongAdder()).increment();}
101		*
102		* <p>This class and its views and iterators implement all of the
103		* <em>optional</em> methods of the {@link Map} and {@link Iterator}
104		* interfaces.
105		*
106	<	* <p> Like {@link Hashtable} but unlike {@link HashMap}, this class
107	<	* does <em>not</em> allow <tt>null</tt> to be used as a key or value.
106	>	* <p>Like {@link Hashtable} but unlike {@link HashMap}, this class
107	>	* does <em>not</em> allow {@code null} to be used as a key or value.
108	>	*
109	>	* <p>ConcurrentHashMaps support sequential and parallel operations
110	>	* bulk operations. (Parallel forms use the {@link
111	>	* ForkJoinPool#commonPool()}). Tasks that may be used in other
112	>	* contexts are available in class {@link ForkJoinTasks}. These
113	>	* operations are designed to be safely, and often sensibly, applied
114	>	* even with maps that are being concurrently updated by other
115	>	* threads; for example, when computing a snapshot summary of the
116	>	* values in a shared registry.  There are three kinds of operation,
117	>	* each with four forms, accepting functions with Keys, Values,
118	>	* Entries, and (Key, Value) arguments and/or return values. Because
119	>	* the elements of a ConcurrentHashMap are not ordered in any
120	>	* particular way, and may be processed in different orders in
121	>	* different parallel executions, the correctness of supplied
122	>	* functions should not depend on any ordering, or on any other
123	>	* objects or values that may transiently change while computation is
124	>	* in progress; and except for forEach actions, should ideally be
125	>	* side-effect-free.
126	>	*
127	>	* <ul>
128	>	* <li> forEach: Perform a given action on each element.
129	>	* A variant form applies a given transformation on each element
130	>	* before performing the action.</li>
131	>	*
132	>	* <li> search: Return the first available non-null result of
133	>	* applying a given function on each element; skipping further
134	>	* search when a result is found.</li>
135	>	*
136	>	* <li> reduce: Accumulate each element.  The supplied reduction
137	>	* function cannot rely on ordering (more formally, it should be
138	>	* both associative and commutative).  There are five variants:
139	>	*
140	>	* <ul>
141	>	*
142	>	* <li> Plain reductions. (There is not a form of this method for
143	>	* (key, value) function arguments since there is no corresponding
144	>	* return type.)</li>
145	>	*
146	>	* <li> Mapped reductions that accumulate the results of a given
147	>	* function applied to each element.</li>
148	>	*
149	>	* <li> Reductions to scalar doubles, longs, and ints, using a
150	>	* given basis value.</li>
151	>	*
152	>	* </ul>
153	>	* </li>
154	>	* </ul>
155	>	*
156	>	* <p>The concurrency properties of bulk operations follow
157	>	* from those of ConcurrentHashMap: Any non-null result returned
158	>	* from {@code get(key)} and related access methods bears a
159	>	* happens-before relation with the associated insertion or
160	>	* update.  The result of any bulk operation reflects the
161	>	* composition of these per-element relations (but is not
162	>	* necessarily atomic with respect to the map as a whole unless it
163	>	* is somehow known to be quiescent).  Conversely, because keys
164	>	* and values in the map are never null, null serves as a reliable
165	>	* atomic indicator of the current lack of any result.  To
166	>	* maintain this property, null serves as an implicit basis for
167	>	* all non-scalar reduction operations. For the double, long, and
168	>	* int versions, the basis should be one that, when combined with
169	>	* any other value, returns that other value (more formally, it
170	>	* should be the identity element for the reduction). Most common
171	>	* reductions have these properties; for example, computing a sum
172	>	* with basis 0 or a minimum with basis MAX_VALUE.
173	>	*
174	>	* <p>Search and transformation functions provided as arguments
175	>	* should similarly return null to indicate the lack of any result
176	>	* (in which case it is not used). In the case of mapped
177	>	* reductions, this also enables transformations to serve as
178	>	* filters, returning null (or, in the case of primitive
179	>	* specializations, the identity basis) if the element should not
180	>	* be combined. You can create compound transformations and
181	>	* filterings by composing them yourself under this "null means
182	>	* there is nothing there now" rule before using them in search or
183	>	* reduce operations.
184	>	*
185	>	* <p>Methods accepting and/or returning Entry arguments maintain
186	>	* key-value associations. They may be useful for example when
187	>	* finding the key for the greatest value. Note that "plain" Entry
188	>	* arguments can be supplied using {@code new
189	>	* AbstractMap.SimpleEntry(k,v)}.
190	>	*
191	>	* <p>Bulk operations may complete abruptly, throwing an
192	>	* exception encountered in the application of a supplied
193	>	* function. Bear in mind when handling such exceptions that other
194	>	* concurrently executing functions could also have thrown
195	>	* exceptions, or would have done so if the first exception had
196	>	* not occurred.
197	>	*
198	>	* <p>Speedups for parallel compared to sequential forms are common
199	>	* but not guaranteed.  Parallel operations involving brief functions
200	>	* on small maps may execute more slowly than sequential forms if the
201	>	* underlying work to parallelize the computation is more expensive
202	>	* than the computation itself.  Similarly, parallelization may not
203	>	* lead to much actual parallelism if all processors are busy
204	>	* performing unrelated tasks.
205	>	*
206	>	* <p>All arguments to all task methods must be non-null.
207		*
208		* <p>This class is a member of the
209	<	* <a href="{@docRoot}/../guide/collections/index.html">
209	>	* <a href="{@docRoot}/../technotes/guides/collections/index.html">
210		* Java Collections Framework</a>.
211		*
212		* @since 1.5
#	Line 70 | Line 214 | import java.io.ObjectOutputStream;
214		* @param <K> the type of keys maintained by this map
215		* @param <V> the type of mapped values
216		*/
217	<	public class ConcurrentHashMap<K, V> extends AbstractMap<K, V>
218	<	implements ConcurrentMap<K, V>, Serializable {
217	>	public class ConcurrentHashMap<K,V>
218	>	implements ConcurrentMap<K,V>, Serializable {
219		private static final long serialVersionUID = 7249069246763182397L;
220
221		/*
222	<	* The basic strategy is to subdivide the table among Segments,
223	<	* each of which itself is a concurrently readable hash table.
222	>	* Overview:
223	>	*
224	>	* The primary design goal of this hash table is to maintain
225	>	* concurrent readability (typically method get(), but also
226	>	* iterators and related methods) while minimizing update
227	>	* contention. Secondary goals are to keep space consumption about
228	>	* the same or better than java.util.HashMap, and to support high
229	>	* initial insertion rates on an empty table by many threads.
230	>	*
231	>	* Each key-value mapping is held in a Node.  Because Node key
232	>	* fields can contain special values, they are defined using plain
233	>	* Object types (not type "K"). This leads to a lot of explicit
234	>	* casting (and many explicit warning suppressions to tell
235	>	* compilers not to complain about it). It also allows some of the
236	>	* public methods to be factored into a smaller number of internal
237	>	* methods (although sadly not so for the five variants of
238	>	* put-related operations). The validation-based approach
239	>	* explained below leads to a lot of code sprawl because
240	>	* retry-control precludes factoring into smaller methods.
241	>	*
242	>	* The table is lazily initialized to a power-of-two size upon the
243	>	* first insertion.  Each bin in the table normally contains a
244	>	* list of Nodes (most often, the list has only zero or one Node).
245	>	* Table accesses require volatile/atomic reads, writes, and
246	>	* CASes.  Because there is no other way to arrange this without
247	>	* adding further indirections, we use intrinsics
248	>	* (sun.misc.Unsafe) operations.  The lists of nodes within bins
249	>	* are always accurately traversable under volatile reads, so long
250	>	* as lookups check hash code and non-nullness of value before
251	>	* checking key equality.
252	>	*
253	>	* We use the top (sign) bit of Node hash fields for control
254	>	* purposes -- it is available anyway because of addressing
255	>	* constraints.  Nodes with negative hash fields are forwarding
256	>	* nodes to either TreeBins or resized tables.  The lower 31 bits
257	>	* of each normal Node's hash field contain a transformation of
258	>	* the key's hash code.
259	>	*
260	>	* Insertion (via put or its variants) of the first node in an
261	>	* empty bin is performed by just CASing it to the bin.  This is
262	>	* by far the most common case for put operations under most
263	>	* key/hash distributions.  Other update operations (insert,
264	>	* delete, and replace) require locks.  We do not want to waste
265	>	* the space required to associate a distinct lock object with
266	>	* each bin, so instead use the first node of a bin list itself as
267	>	* a lock. Locking support for these locks relies on builtin
268	>	* "synchronized" monitors.
269	>	*
270	>	* Using the first node of a list as a lock does not by itself
271	>	* suffice though: When a node is locked, any update must first
272	>	* validate that it is still the first node after locking it, and
273	>	* retry if not. Because new nodes are always appended to lists,
274	>	* once a node is first in a bin, it remains first until deleted
275	>	* or the bin becomes invalidated (upon resizing).  However,
276	>	* operations that only conditionally update may inspect nodes
277	>	* until the point of update. This is a converse of sorts to the
278	>	* lazy locking technique described by Herlihy & Shavit.
279	>	*
280	>	* The main disadvantage of per-bin locks is that other update
281	>	* operations on other nodes in a bin list protected by the same
282	>	* lock can stall, for example when user equals() or mapping
283	>	* functions take a long time.  However, statistically, under
284	>	* random hash codes, this is not a common problem.  Ideally, the
285	>	* frequency of nodes in bins follows a Poisson distribution
286	>	* (http://en.wikipedia.org/wiki/Poisson_distribution) with a
287	>	* parameter of about 0.5 on average, given the resizing threshold
288	>	* of 0.75, although with a large variance because of resizing
289	>	* granularity. Ignoring variance, the expected occurrences of
290	>	* list size k are (exp(-0.5) * pow(0.5, k) / factorial(k)). The
291	>	* first values are:
292	>	*
293	>	* 0:    0.60653066
294	>	* 1:    0.30326533
295	>	* 2:    0.07581633
296	>	* 3:    0.01263606
297	>	* 4:    0.00157952
298	>	* 5:    0.00015795
299	>	* 6:    0.00001316
300	>	* 7:    0.00000094
301	>	* 8:    0.00000006
302	>	* more: less than 1 in ten million
303	>	*
304	>	* Lock contention probability for two threads accessing distinct
305	>	* elements is roughly 1 / (8 * #elements) under random hashes.
306	>	*
307	>	* Actual hash code distributions encountered in practice
308	>	* sometimes deviate significantly from uniform randomness.  This
309	>	* includes the case when N > (1<<30), so some keys MUST collide.
310	>	* Similarly for dumb or hostile usages in which multiple keys are
311	>	* designed to have identical hash codes. Also, although we guard
312	>	* against the worst effects of this (see method spread), sets of
313	>	* hashes may differ only in bits that do not impact their bin
314	>	* index for a given power-of-two mask.  So we use a secondary
315	>	* strategy that applies when the number of nodes in a bin exceeds
316	>	* a threshold, and at least one of the keys implements
317	>	* Comparable.  These TreeBins use a balanced tree to hold nodes
318	>	* (a specialized form of red-black trees), bounding search time
319	>	* to O(log N).  Each search step in a TreeBin is around twice as
320	>	* slow as in a regular list, but given that N cannot exceed
321	>	* (1<<64) (before running out of addresses) this bounds search
322	>	* steps, lock hold times, etc, to reasonable constants (roughly
323	>	* 100 nodes inspected per operation worst case) so long as keys
324	>	* are Comparable (which is very common -- String, Long, etc).
325	>	* TreeBin nodes (TreeNodes) also maintain the same "next"
326	>	* traversal pointers as regular nodes, so can be traversed in
327	>	* iterators in the same way.
328	>	*
329	>	* The table is resized when occupancy exceeds a percentage
330	>	* threshold (nominally, 0.75, but see below).  Any thread
331	>	* noticing an overfull bin may assist in resizing after the
332	>	* initiating thread allocates and sets up the replacement
333	>	* array. However, rather than stalling, these other threads may
334	>	* proceed with insertions etc.  The use of TreeBins shields us
335	>	* from the worst case effects of overfilling while resizes are in
336	>	* progress.  Resizing proceeds by transferring bins, one by one,
337	>	* from the table to the next table. To enable concurrency, the
338	>	* next table must be (incrementally) prefilled with place-holders
339	>	* serving as reverse forwarders to the old table.  Because we are
340	>	* using power-of-two expansion, the elements from each bin must
341	>	* either stay at same index, or move with a power of two
342	>	* offset. We eliminate unnecessary node creation by catching
343	>	* cases where old nodes can be reused because their next fields
344	>	* won't change.  On average, only about one-sixth of them need
345	>	* cloning when a table doubles. The nodes they replace will be
346	>	* garbage collectable as soon as they are no longer referenced by
347	>	* any reader thread that may be in the midst of concurrently
348	>	* traversing table.  Upon transfer, the old table bin contains
349	>	* only a special forwarding node (with hash field "MOVED") that
350	>	* contains the next table as its key. On encountering a
351	>	* forwarding node, access and update operations restart, using
352	>	* the new table.
353	>	*
354	>	* Each bin transfer requires its bin lock, which can stall
355	>	* waiting for locks while resizing. However, because other
356	>	* threads can join in and help resize rather than contend for
357	>	* locks, average aggregate waits become shorter as resizing
358	>	* progresses.  The transfer operation must also ensure that all
359	>	* accessible bins in both the old and new table are usable by any
360	>	* traversal.  This is arranged by proceeding from the last bin
361	>	* (table.length - 1) up towards the first.  Upon seeing a
362	>	* forwarding node, traversals (see class Traverser) arrange to
363	>	* move to the new table without revisiting nodes.  However, to
364	>	* ensure that no intervening nodes are skipped, bin splitting can
365	>	* only begin after the associated reverse-forwarders are in
366	>	* place.
367	>	*
368	>	* The traversal scheme also applies to partial traversals of
369	>	* ranges of bins (via an alternate Traverser constructor)
370	>	* to support partitioned aggregate operations.  Also, read-only
371	>	* operations give up if ever forwarded to a null table, which
372	>	* provides support for shutdown-style clearing, which is also not
373	>	* currently implemented.
374	>	*
375	>	* Lazy table initialization minimizes footprint until first use,
376	>	* and also avoids resizings when the first operation is from a
377	>	* putAll, constructor with map argument, or deserialization.
378	>	* These cases attempt to override the initial capacity settings,
379	>	* but harmlessly fail to take effect in cases of races.
380	>	*
381	>	* The element count is maintained using a specialization of
382	>	* LongAdder. We need to incorporate a specialization rather than
383	>	* just use a LongAdder in order to access implicit
384	>	* contention-sensing that leads to creation of multiple
385	>	* Cells.  The counter mechanics avoid contention on
386	>	* updates but can encounter cache thrashing if read too
387	>	* frequently during concurrent access. To avoid reading so often,
388	>	* resizing under contention is attempted only upon adding to a
389	>	* bin already holding two or more nodes. Under uniform hash
390	>	* distributions, the probability of this occurring at threshold
391	>	* is around 13%, meaning that only about 1 in 8 puts check
392	>	* threshold (and after resizing, many fewer do so). The bulk
393	>	* putAll operation further reduces contention by only committing
394	>	* count updates upon these size checks.
395	>	*
396	>	* Maintaining API and serialization compatibility with previous
397	>	* versions of this class introduces several oddities. Mainly: We
398	>	* leave untouched but unused constructor arguments refering to
399	>	* concurrencyLevel. We accept a loadFactor constructor argument,
400	>	* but apply it only to initial table capacity (which is the only
401	>	* time that we can guarantee to honor it.) We also declare an
402	>	* unused "Segment" class that is instantiated in minimal form
403	>	* only when serializing.
404		*/
405
406		/* ---------------- Constants -------------- */
407
408		/**
409	<	* The default initial capacity for this table,
410	<	* used when not otherwise specified in a constructor.
409	>	* The largest possible table capacity.  This value must be
410	>	* exactly 1<<30 to stay within Java array allocation and indexing
411	>	* bounds for power of two table sizes, and is further required
412	>	* because the top two bits of 32bit hash fields are used for
413	>	* control purposes.
414		*/
415	<	static final int DEFAULT_INITIAL_CAPACITY = 16;
415	>	private static final int MAXIMUM_CAPACITY = 1 << 30;
416
417		/**
418	<	* The default load factor for this table, used when not
419	<	* otherwise specified in a constructor.
418	>	* The default initial table capacity.  Must be a power of 2
419	>	* (i.e., at least 1) and at most MAXIMUM_CAPACITY.
420		*/
421	<	static final float DEFAULT_LOAD_FACTOR = 0.75f;
421	>	private static final int DEFAULT_CAPACITY = 16;
422
423		/**
424	<	* The default concurrency level for this table, used when not
425	<	* otherwise specified in a constructor.
424	>	* The largest possible (non-power of two) array size.
425	>	* Needed by toArray and related methods.
426		*/
427	<	static final int DEFAULT_CONCURRENCY_LEVEL = 16;
427	>	static final int MAX_ARRAY_SIZE = Integer.MAX_VALUE - 8;
428
429		/**
430	<	* The maximum capacity, used if a higher value is implicitly
431	<	* 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.
430	>	* The default concurrency level for this table. Unused but
431	>	* defined for compatibility with previous versions of this class.
432		*/
433	<	static final int MAXIMUM_CAPACITY = 1 << 30;
433	>	private static final int DEFAULT_CONCURRENCY_LEVEL = 16;
434
435		/**
436	<	* The maximum number of segments to allow; used to bound
437	<	* constructor arguments.
436	>	* The load factor for this table. Overrides of this value in
437	>	* constructors affect only the initial table capacity.  The
438	>	* actual floating point value isn't normally used -- it is
439	>	* simpler to use expressions such as {@code n - (n >>> 2)} for
440	>	* the associated resizing threshold.
441		*/
442	<	static final int MAX_SEGMENTS = 1 << 16; // slightly conservative
442	>	private static final float LOAD_FACTOR = 0.75f;
443
444		/**
445	<	* Number of unsynchronized retries in size and containsValue
446	<	* methods before resorting to locking. This is used to avoid
447	<	* unbounded retries if tables undergo continuous modification
120	<	* which would make it impossible to obtain an accurate result.
445	>	* The bin count threshold for using a tree rather than list for a
446	>	* bin.  The value reflects the approximate break-even point for
447	>	* using tree-based operations.
448		*/
449	<	static final int RETRIES_BEFORE_LOCK = 2;
449	>	private static final int TREE_THRESHOLD = 8;
450	>
451	>	/**
452	>	* Minimum number of rebinnings per transfer step. Ranges are
453	>	* subdivided to allow multiple resizer threads.  This value
454	>	* serves as a lower bound to avoid resizers encountering
455	>	* excessive memory contention.  The value should be at least
456	>	* DEFAULT_CAPACITY.
457	>	*/
458	>	private static final int MIN_TRANSFER_STRIDE = 16;
459	>
460	>	/*
461	>	* Encodings for Node hash fields. See above for explanation.
462	>	*/
463	>	static final int MOVED     = 0x80000000; // hash field for forwarding nodes
464	>	static final int HASH_BITS = 0x7fffffff; // usable bits of normal node hash
465	>
466	>	/** Number of CPUS, to place bounds on some sizings */
467	>	static final int NCPU = Runtime.getRuntime().availableProcessors();
468	>
469	>	/* ---------------- Counters -------------- */
470	>
471	>	// Adapted from LongAdder and Striped64.
472	>	// See their internal docs for explanation.
473	>
474	>	// A padded cell for distributing counts
475	>	static final class Cell {
476	>	volatile long p0, p1, p2, p3, p4, p5, p6;
477	>	volatile long value;
478	>	volatile long q0, q1, q2, q3, q4, q5, q6;
479	>	Cell(long x) { value = x; }
480	>	}
481
482		/* ---------------- Fields -------------- */
483
484		/**
485	<	* Mask value for indexing into segments. The upper bits of a
486	<	* key's hash code are used to choose the segment.
485	>	* The array of bins. Lazily initialized upon first insertion.
486	>	* Size is always a power of two. Accessed directly by iterators.
487		*/
488	<	final int segmentMask;
488	>	transient volatile Node<V>[] table;
489
490		/**
491	<	* Shift value for indexing within segments.
491	>	* The next table to use; non-null only while resizing.
492		*/
493	<	final int segmentShift;
493	>	private transient volatile Node<V>[] nextTable;
494
495		/**
496	<	* The segments, each of which is a specialized hash table
496	>	* Base counter value, used mainly when there is no contention,
497	>	* but also as a fallback during table initialization
498	>	* races. Updated via CAS.
499		*/
500	<	final Segment<K,V>[] segments;
500	>	private transient volatile long baseCount;
501
502	<	transient Set<K> keySet;
503	<	transient Set<Map.Entry<K,V>> entrySet;
504	<	transient Collection<V> values;
502	>	/**
503	>	* Table initialization and resizing control.  When negative, the
504	>	* table is being initialized or resized: -1 for initialization,
505	>	* else -(1 + the number of active resizing threads).  Otherwise,
506	>	* when table is null, holds the initial table size to use upon
507	>	* creation, or 0 for default. After initialization, holds the
508	>	* next element count value upon which to resize the table.
509	>	*/
510	>	private transient volatile int sizeCtl;
511
512	<	/* ---------------- Small Utilities -------------- */
512	>	/**
513	>	* The next table index (plus one) to split while resizing.
514	>	*/
515	>	private transient volatile int transferIndex;
516
517		/**
518	<	* Returns a hash code for non-null Object x.
150	<	* Uses the same hash code spreader as most other java.util hash tables.
151	<	* @param x the object serving as a key
152	<	* @return the hash code
518	>	* The least available table index to split while resizing.
519		*/
520	<	static int hash(Object x) {
521	<	int h = x.hashCode();
522	<	h += ~(h << 9);
523	<	h ^=  (h >>> 14);
524	<	h +=  (h << 4);
525	<	h ^=  (h >>> 10);
160	<	return h;
161	<	}
520	>	private transient volatile int transferOrigin;
521	>
522	>	/**
523	>	* Spinlock (locked via CAS) used when resizing and/or creating Cells.
524	>	*/
525	>	private transient volatile int cellsBusy;
526
527		/**
528	<	* 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
528	>	* Table of counter cells. When non-null, size is a power of 2.
529		*/
530	<	final Segment<K,V> segmentFor(int hash) {
531	<	return segments[(hash >>> segmentShift) & segmentMask];
530	>	private transient volatile Cell[] counterCells;
531	>
532	>	// views
533	>	private transient KeySetView<K,V> keySet;
534	>	private transient ValuesView<K,V> values;
535	>	private transient EntrySetView<K,V> entrySet;
536	>
537	>	/** For serialization compatibility. Null unless serialized; see below */
538	>	private Segment<K,V>[] segments;
539	>
540	>	/* ---------------- Table element access -------------- */
541	>
542	>	/*
543	>	* Volatile access methods are used for table elements as well as
544	>	* elements of in-progress next table while resizing.  Uses are
545	>	* null checked by callers, and implicitly bounds-checked, relying
546	>	* on the invariants that tab arrays have non-zero size, and all
547	>	* indices are masked with (tab.length - 1) which is never
548	>	* negative and always less than length. Note that, to be correct
549	>	* wrt arbitrary concurrency errors by users, bounds checks must
550	>	* operate on local variables, which accounts for some odd-looking
551	>	* inline assignments below.
552	>	*/
553	>
554	>	@SuppressWarnings("unchecked") static final <V> Node<V> tabAt
555	>	(Node<V>[] tab, int i) { // used by Traverser
556	>	return (Node<V>)U.getObjectVolatile(tab, ((long)i << ASHIFT) + ABASE);
557	>	}
558	>
559	>	private static final <V> boolean casTabAt
560	>	(Node<V>[] tab, int i, Node<V> c, Node<V> v) {
561	>	return U.compareAndSwapObject(tab, ((long)i << ASHIFT) + ABASE, c, v);
562	>	}
563	>
564	>	private static final <V> void setTabAt
565	>	(Node<V>[] tab, int i, Node<V> v) {
566	>	U.putObjectVolatile(tab, ((long)i << ASHIFT) + ABASE, v);
567		}
568
569	<	/* ---------------- Inner Classes -------------- */
569	>	/* ---------------- Nodes -------------- */
570
571		/**
572	<	* ConcurrentHashMap list entry. Note that this is never exported
573	<	* out as a user-visible Map.Entry.
574	<	*
575	<	* Because the value field is volatile, not final, it is legal wrt
576	<	* the Java Memory Model for an unsynchronized reader to see null
577	<	* instead of initial value when read via a data race.  Although a
578	<	* reordering leading to this is not likely to ever actually
579	<	* occur, the Segment.readValueUnderLock method is used as a
183	<	* backup in case a null (pre-initialized) value is ever seen in
184	<	* an unsynchronized access method.
572	>	* Key-value entry. Note that this is never exported out as a
573	>	* user-visible Map.Entry (see MapEntry below). Nodes with a hash
574	>	* field of MOVED are special, and do not contain user keys or
575	>	* values.  Otherwise, keys are never null, and null val fields
576	>	* indicate that a node is in the process of being deleted or
577	>	* created. For purposes of read-only access, a key may be read
578	>	* before a val, but can only be used after checking val to be
579	>	* non-null.
580		*/
581	<	static final class HashEntry<K,V> {
187	<	final K key;
581	>	static class Node<V> {
582		final int hash;
583	<	volatile V value;
584	<	final HashEntry<K,V> next;
583	>	final Object key;
584	>	volatile V val;
585	>	volatile Node<V> next;
586
587	<	HashEntry(K key, int hash, HashEntry<K,V> next, V value) {
193	<	this.key = key;
587	>	Node(int hash, Object key, V val, Node<V> next) {
588		this.hash = hash;
589	+	this.key = key;
590	+	this.val = val;
591		this.next = next;
196	–	this.value = value;
592		}
198	–
199	–	@SuppressWarnings("unchecked")
200	–	static final <K,V> HashEntry<K,V>[] newArray(int i) {
201	–	return new HashEntry[i];
202	–	}
593		}
594
595	+	/* ---------------- TreeBins -------------- */
596	+
597		/**
598	<	* Segments are specialized versions of hash tables.  This
599	<	* subclasses from ReentrantLock opportunistically, just to
600	<	* simplify some locking and avoid separate construction.
601	<	*/
602	<	static final class Segment<K,V> extends ReentrantLock implements Serializable {
603	<	/*
604	<	* Segments maintain a table of entry lists that are ALWAYS
605	<	* kept in a consistent state, so can be read without locking.
606	<	* Next fields of nodes are immutable (final).  All list
607	<	* additions are performed at the front of each bin. This
608	<	* makes it easy to check changes, and also fast to traverse.
609	<	* When nodes would otherwise be changed, new nodes are
610	<	* created to replace them. This works well for hash tables
611	<	* 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	<	*/
598	>	* Nodes for use in TreeBins
599	>	*/
600	>	static final class TreeNode<V> extends Node<V> {
601	>	TreeNode<V> parent;  // red-black tree links
602	>	TreeNode<V> left;
603	>	TreeNode<V> right;
604	>	TreeNode<V> prev;    // needed to unlink next upon deletion
605	>	boolean red;
606	>
607	>	TreeNode(int hash, Object key, V val, Node<V> next, TreeNode<V> parent) {
608	>	super(hash, key, val, next);
609	>	this.parent = parent;
610	>	}
611	>	}
612
613	+	/**
614	+	* A specialized form of red-black tree for use in bins
615	+	* whose size exceeds a threshold.
616	+	*
617	+	* TreeBins use a special form of comparison for search and
618	+	* related operations (which is the main reason we cannot use
619	+	* existing collections such as TreeMaps). TreeBins contain
620	+	* Comparable elements, but may contain others, as well as
621	+	* elements that are Comparable but not necessarily Comparable<T>
622	+	* for the same T, so we cannot invoke compareTo among them. To
623	+	* handle this, the tree is ordered primarily by hash value, then
624	+	* by getClass().getName() order, and then by Comparator order
625	+	* among elements of the same class.  On lookup at a node, if
626	+	* elements are not comparable or compare as 0, both left and
627	+	* right children may need to be searched in the case of tied hash
628	+	* values. (This corresponds to the full list search that would be
629	+	* necessary if all elements were non-Comparable and had tied
630	+	* hashes.)  The red-black balancing code is updated from
631	+	* pre-jdk-collections
632	+	* (http://gee.cs.oswego.edu/dl/classes/collections/RBCell.java)
633	+	* based in turn on Cormen, Leiserson, and Rivest "Introduction to
634	+	* Algorithms" (CLR).
635	+	*
636	+	* TreeBins also maintain a separate locking discipline than
637	+	* regular bins. Because they are forwarded via special MOVED
638	+	* nodes at bin heads (which can never change once established),
639	+	* we cannot use those nodes as locks. Instead, TreeBin
640	+	* extends AbstractQueuedSynchronizer to support a simple form of
641	+	* read-write lock. For update operations and table validation,
642	+	* the exclusive form of lock behaves in the same way as bin-head
643	+	* locks. However, lookups use shared read-lock mechanics to allow
644	+	* multiple readers in the absence of writers.  Additionally,
645	+	* these lookups do not ever block: While the lock is not
646	+	* available, they proceed along the slow traversal path (via
647	+	* next-pointers) until the lock becomes available or the list is
648	+	* exhausted, whichever comes first. (These cases are not fast,
649	+	* but maximize aggregate expected throughput.)  The AQS mechanics
650	+	* for doing this are straightforward.  The lock state is held as
651	+	* AQS getState().  Read counts are negative; the write count (1)
652	+	* is positive.  There are no signalling preferences among readers
653	+	* and writers. Since we don't need to export full Lock API, we
654	+	* just override the minimal AQS methods and use them directly.
655	+	*/
656	+	static final class TreeBin<V> extends AbstractQueuedSynchronizer {
657		private static final long serialVersionUID = 2249069246763182397L;
658	+	transient TreeNode<V> root;  // root of tree
659	+	transient TreeNode<V> first; // head of next-pointer list
660
661	<	/**
662	<	* The number of elements in this segment's region.
663	<	*/
664	<	transient volatile int count;
661	>	/* AQS overrides */
662	>	public final boolean isHeldExclusively() { return getState() > 0; }
663	>	public final boolean tryAcquire(int ignore) {
664	>	if (compareAndSetState(0, 1)) {
665	>	setExclusiveOwnerThread(Thread.currentThread());
666	>	return true;
667	>	}
668	>	return false;
669	>	}
670	>	public final boolean tryRelease(int ignore) {
671	>	setExclusiveOwnerThread(null);
672	>	setState(0);
673	>	return true;
674	>	}
675	>	public final int tryAcquireShared(int ignore) {
676	>	for (int c;;) {
677	>	if ((c = getState()) > 0)
678	>	return -1;
679	>	if (compareAndSetState(c, c -1))
680	>	return 1;
681	>	}
682	>	}
683	>	public final boolean tryReleaseShared(int ignore) {
684	>	int c;
685	>	do {} while (!compareAndSetState(c = getState(), c + 1));
686	>	return c == -1;
687	>	}
688	>
689	>	/** From CLR */
690	>	private void rotateLeft(TreeNode<V> p) {
691	>	if (p != null) {
692	>	TreeNode<V> r = p.right, pp, rl;
693	>	if ((rl = p.right = r.left) != null)
694	>	rl.parent = p;
695	>	if ((pp = r.parent = p.parent) == null)
696	>	root = r;
697	>	else if (pp.left == p)
698	>	pp.left = r;
699	>	else
700	>	pp.right = r;
701	>	r.left = p;
702	>	p.parent = r;
703	>	}
704	>	}
705	>
706	>	/** From CLR */
707	>	private void rotateRight(TreeNode<V> p) {
708	>	if (p != null) {
709	>	TreeNode<V> l = p.left, pp, lr;
710	>	if ((lr = p.left = l.right) != null)
711	>	lr.parent = p;
712	>	if ((pp = l.parent = p.parent) == null)
713	>	root = l;
714	>	else if (pp.right == p)
715	>	pp.right = l;
716	>	else
717	>	pp.left = l;
718	>	l.right = p;
719	>	p.parent = l;
720	>	}
721	>	}
722
723		/**
724	<	* Number of updates that alter the size of the table. This is
725	<	* 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.
724	>	* Returns the TreeNode (or null if not found) for the given key
725	>	* starting at given root.
726		*/
727	<	transient int modCount;
727	>	@SuppressWarnings("unchecked") final TreeNode<V> getTreeNode
728	>	(int h, Object k, TreeNode<V> p) {
729	>	Class<?> c = k.getClass();
730	>	while (p != null) {
731	>	int dir, ph;  Object pk; Class<?> pc;
732	>	if ((ph = p.hash) == h) {
733	>	if ((pk = p.key) == k || k.equals(pk))
734	>	return p;
735	>	if (c != (pc = pk.getClass()) ||
736	>	!(k instanceof Comparable) ||
737	>	(dir = ((Comparable)k).compareTo((Comparable)pk)) == 0) {
738	>	if ((dir = (c == pc) ? 0 :
739	>	c.getName().compareTo(pc.getName())) == 0) {
740	>	TreeNode<V> r = null, pl, pr; // check both sides
741	>	if ((pr = p.right) != null && h >= pr.hash &&
742	>	(r = getTreeNode(h, k, pr)) != null)
743	>	return r;
744	>	else if ((pl = p.left) != null && h <= pl.hash)
745	>	dir = -1;
746	>	else // nothing there
747	>	return null;
748	>	}
749	>	}
750	>	}
751	>	else
752	>	dir = (h < ph) ? -1 : 1;
753	>	p = (dir > 0) ? p.right : p.left;
754	>	}
755	>	return null;
756	>	}
757
758		/**
759	<	* The table is rehashed when its size exceeds this threshold.
760	<	* (The value of this field is always <tt>(int)(capacity *
761	<	* loadFactor)</tt>.)
759	>	* Wrapper for getTreeNode used by CHM.get. Tries to obtain
760	>	* read-lock to call getTreeNode, but during failure to get
761	>	* lock, searches along next links.
762		*/
763	<	transient int threshold;
763	>	final V getValue(int h, Object k) {
764	>	Node<V> r = null;
765	>	int c = getState(); // Must read lock state first
766	>	for (Node<V> e = first; e != null; e = e.next) {
767	>	if (c <= 0 && compareAndSetState(c, c - 1)) {
768	>	try {
769	>	r = getTreeNode(h, k, root);
770	>	} finally {
771	>	releaseShared(0);
772	>	}
773	>	break;
774	>	}
775	>	else if (e.hash == h && k.equals(e.key)) {
776	>	r = e;
777	>	break;
778	>	}
779	>	else
780	>	c = getState();
781	>	}
782	>	return r == null ? null : r.val;
783	>	}
784
785		/**
786	<	* The per-segment table.
786	>	* Finds or adds a node.
787	>	* @return null if added
788		*/
789	<	transient volatile HashEntry<K,V>[] table;
789	>	@SuppressWarnings("unchecked") final TreeNode<V> putTreeNode
790	>	(int h, Object k, V v) {
791	>	Class<?> c = k.getClass();
792	>	TreeNode<V> pp = root, p = null;
793	>	int dir = 0;
794	>	while (pp != null) { // find existing node or leaf to insert at
795	>	int ph;  Object pk; Class<?> pc;
796	>	p = pp;
797	>	if ((ph = p.hash) == h) {
798	>	if ((pk = p.key) == k || k.equals(pk))
799	>	return p;
800	>	if (c != (pc = pk.getClass()) ||
801	>	!(k instanceof Comparable) ||
802	>	(dir = ((Comparable)k).compareTo((Comparable)pk)) == 0) {
803	>	TreeNode<V> s = null, r = null, pr;
804	>	if ((dir = (c == pc) ? 0 :
805	>	c.getName().compareTo(pc.getName())) == 0) {
806	>	if ((pr = p.right) != null && h >= pr.hash &&
807	>	(r = getTreeNode(h, k, pr)) != null)
808	>	return r;
809	>	else // continue left
810	>	dir = -1;
811	>	}
812	>	else if ((pr = p.right) != null && h >= pr.hash)
813	>	s = pr;
814	>	if (s != null && (r = getTreeNode(h, k, s)) != null)
815	>	return r;
816	>	}
817	>	}
818	>	else
819	>	dir = (h < ph) ? -1 : 1;
820	>	pp = (dir > 0) ? p.right : p.left;
821	>	}
822	>
823	>	TreeNode<V> f = first;
824	>	TreeNode<V> x = first = new TreeNode<V>(h, k, v, f, p);
825	>	if (p == null)
826	>	root = x;
827	>	else { // attach and rebalance; adapted from CLR
828	>	TreeNode<V> xp, xpp;
829	>	if (f != null)
830	>	f.prev = x;
831	>	if (dir <= 0)
832	>	p.left = x;
833	>	else
834	>	p.right = x;
835	>	x.red = true;
836	>	while (x != null && (xp = x.parent) != null && xp.red &&
837	>	(xpp = xp.parent) != null) {
838	>	TreeNode<V> xppl = xpp.left;
839	>	if (xp == xppl) {
840	>	TreeNode<V> y = xpp.right;
841	>	if (y != null && y.red) {
842	>	y.red = false;
843	>	xp.red = false;
844	>	xpp.red = true;
845	>	x = xpp;
846	>	}
847	>	else {
848	>	if (x == xp.right) {
849	>	rotateLeft(x = xp);
850	>	xpp = (xp = x.parent) == null ? null : xp.parent;
851	>	}
852	>	if (xp != null) {
853	>	xp.red = false;
854	>	if (xpp != null) {
855	>	xpp.red = true;
856	>	rotateRight(xpp);
857	>	}
858	>	}
859	>	}
860	>	}
861	>	else {
862	>	TreeNode<V> y = xppl;
863	>	if (y != null && y.red) {
864	>	y.red = false;
865	>	xp.red = false;
866	>	xpp.red = true;
867	>	x = xpp;
868	>	}
869	>	else {
870	>	if (x == xp.left) {
871	>	rotateRight(x = xp);
872	>	xpp = (xp = x.parent) == null ? null : xp.parent;
873	>	}
874	>	if (xp != null) {
875	>	xp.red = false;
876	>	if (xpp != null) {
877	>	xpp.red = true;
878	>	rotateLeft(xpp);
879	>	}
880	>	}
881	>	}
882	>	}
883	>	}
884	>	TreeNode<V> r = root;
885	>	if (r != null && r.red)
886	>	r.red = false;
887	>	}
888	>	return null;
889	>	}
890
891		/**
892	<	* The load factor for the hash table.  Even though this value
893	<	* is same for all segments, it is replicated to avoid needing
894	<	* links to outer object.
895	<	* @serial
892	>	* Removes the given node, that must be present before this
893	>	* call.  This is messier than typical red-black deletion code
894	>	* because we cannot swap the contents of an interior node
895	>	* with a leaf successor that is pinned by "next" pointers
896	>	* that are accessible independently of lock. So instead we
897	>	* swap the tree linkages.
898		*/
899	<	final float loadFactor;
899	>	final void deleteTreeNode(TreeNode<V> p) {
900	>	TreeNode<V> next = (TreeNode<V>)p.next; // unlink traversal pointers
901	>	TreeNode<V> pred = p.prev;
902	>	if (pred == null)
903	>	first = next;
904	>	else
905	>	pred.next = next;
906	>	if (next != null)
907	>	next.prev = pred;
908	>	TreeNode<V> replacement;
909	>	TreeNode<V> pl = p.left;
910	>	TreeNode<V> pr = p.right;
911	>	if (pl != null && pr != null) {
912	>	TreeNode<V> s = pr, sl;
913	>	while ((sl = s.left) != null) // find successor
914	>	s = sl;
915	>	boolean c = s.red; s.red = p.red; p.red = c; // swap colors
916	>	TreeNode<V> sr = s.right;
917	>	TreeNode<V> pp = p.parent;
918	>	if (s == pr) { // p was s's direct parent
919	>	p.parent = s;
920	>	s.right = p;
921	>	}
922	>	else {
923	>	TreeNode<V> sp = s.parent;
924	>	if ((p.parent = sp) != null) {
925	>	if (s == sp.left)
926	>	sp.left = p;
927	>	else
928	>	sp.right = p;
929	>	}
930	>	if ((s.right = pr) != null)
931	>	pr.parent = s;
932	>	}
933	>	p.left = null;
934	>	if ((p.right = sr) != null)
935	>	sr.parent = p;
936	>	if ((s.left = pl) != null)
937	>	pl.parent = s;
938	>	if ((s.parent = pp) == null)
939	>	root = s;
940	>	else if (p == pp.left)
941	>	pp.left = s;
942	>	else
943	>	pp.right = s;
944	>	replacement = sr;
945	>	}
946	>	else
947	>	replacement = (pl != null) ? pl : pr;
948	>	TreeNode<V> pp = p.parent;
949	>	if (replacement == null) {
950	>	if (pp == null) {
951	>	root = null;
952	>	return;
953	>	}
954	>	replacement = p;
955	>	}
956	>	else {
957	>	replacement.parent = pp;
958	>	if (pp == null)
959	>	root = replacement;
960	>	else if (p == pp.left)
961	>	pp.left = replacement;
962	>	else
963	>	pp.right = replacement;
964	>	p.left = p.right = p.parent = null;
965	>	}
966	>	if (!p.red) { // rebalance, from CLR
967	>	TreeNode<V> x = replacement;
968	>	while (x != null) {
969	>	TreeNode<V> xp, xpl;
970	>	if (x.red || (xp = x.parent) == null) {
971	>	x.red = false;
972	>	break;
973	>	}
974	>	if (x == (xpl = xp.left)) {
975	>	TreeNode<V> sib = xp.right;
976	>	if (sib != null && sib.red) {
977	>	sib.red = false;
978	>	xp.red = true;
979	>	rotateLeft(xp);
980	>	sib = (xp = x.parent) == null ? null : xp.right;
981	>	}
982	>	if (sib == null)
983	>	x = xp;
984	>	else {
985	>	TreeNode<V> sl = sib.left, sr = sib.right;
986	>	if ((sr == null || !sr.red) &&
987	>	(sl == null || !sl.red)) {
988	>	sib.red = true;
989	>	x = xp;
990	>	}
991	>	else {
992	>	if (sr == null || !sr.red) {
993	>	if (sl != null)
994	>	sl.red = false;
995	>	sib.red = true;
996	>	rotateRight(sib);
997	>	sib = (xp = x.parent) == null ?
998	>	null : xp.right;
999	>	}
1000	>	if (sib != null) {
1001	>	sib.red = (xp == null) ? false : xp.red;
1002	>	if ((sr = sib.right) != null)
1003	>	sr.red = false;
1004	>	}
1005	>	if (xp != null) {
1006	>	xp.red = false;
1007	>	rotateLeft(xp);
1008	>	}
1009	>	x = root;
1010	>	}
1011	>	}
1012	>	}
1013	>	else { // symmetric
1014	>	TreeNode<V> sib = xpl;
1015	>	if (sib != null && sib.red) {
1016	>	sib.red = false;
1017	>	xp.red = true;
1018	>	rotateRight(xp);
1019	>	sib = (xp = x.parent) == null ? null : xp.left;
1020	>	}
1021	>	if (sib == null)
1022	>	x = xp;
1023	>	else {
1024	>	TreeNode<V> sl = sib.left, sr = sib.right;
1025	>	if ((sl == null || !sl.red) &&
1026	>	(sr == null || !sr.red)) {
1027	>	sib.red = true;
1028	>	x = xp;
1029	>	}
1030	>	else {
1031	>	if (sl == null || !sl.red) {
1032	>	if (sr != null)
1033	>	sr.red = false;
1034	>	sib.red = true;
1035	>	rotateLeft(sib);
1036	>	sib = (xp = x.parent) == null ?
1037	>	null : xp.left;
1038	>	}
1039	>	if (sib != null) {
1040	>	sib.red = (xp == null) ? false : xp.red;
1041	>	if ((sl = sib.left) != null)
1042	>	sl.red = false;
1043	>	}
1044	>	if (xp != null) {
1045	>	xp.red = false;
1046	>	rotateRight(xp);
1047	>	}
1048	>	x = root;
1049	>	}
1050	>	}
1051	>	}
1052	>	}
1053	>	}
1054	>	if (p == replacement && (pp = p.parent) != null) {
1055	>	if (p == pp.left) // detach pointers
1056	>	pp.left = null;
1057	>	else if (p == pp.right)
1058	>	pp.right = null;
1059	>	p.parent = null;
1060	>	}
1061	>	}
1062	>	}
1063
1064	<	Segment(int initialCapacity, float lf) {
1065	<	loadFactor = lf;
1066	<	setTable(HashEntry.<K,V>newArray(initialCapacity));
1064	>	/* ---------------- Collision reduction methods -------------- */
1065	>
1066	>	/**
1067	>	* Spreads higher bits to lower, and also forces top bit to 0.
1068	>	* Because the table uses power-of-two masking, sets of hashes
1069	>	* that vary only in bits above the current mask will always
1070	>	* collide. (Among known examples are sets of Float keys holding
1071	>	* consecutive whole numbers in small tables.)  To counter this,
1072	>	* we apply a transform that spreads the impact of higher bits
1073	>	* downward. There is a tradeoff between speed, utility, and
1074	>	* quality of bit-spreading. Because many common sets of hashes
1075	>	* are already reasonably distributed across bits (so don't benefit
1076	>	* from spreading), and because we use trees to handle large sets
1077	>	* of collisions in bins, we don't need excessively high quality.
1078	>	*/
1079	>	private static final int spread(int h) {
1080	>	h ^= (h >>> 18) ^ (h >>> 12);
1081	>	return (h ^ (h >>> 10)) & HASH_BITS;
1082	>	}
1083	>
1084	>	/**
1085	>	* Replaces a list bin with a tree bin if key is comparable.  Call
1086	>	* only when locked.
1087	>	*/
1088	>	private final void replaceWithTreeBin(Node<V>[] tab, int index, Object key) {
1089	>	if (key instanceof Comparable) {
1090	>	TreeBin<V> t = new TreeBin<V>();
1091	>	for (Node<V> e = tabAt(tab, index); e != null; e = e.next)
1092	>	t.putTreeNode(e.hash, e.key, e.val);
1093	>	setTabAt(tab, index, new Node<V>(MOVED, t, null, null));
1094		}
1095	+	}
1096	+
1097	+	/* ---------------- Internal access and update methods -------------- */
1098
1099	<	@SuppressWarnings("unchecked")
1100	<	static final <K,V> Segment<K,V>[] newArray(int i) {
1101	<	return new Segment[i];
1099	>	/** Implementation for get and containsKey */
1100	>	@SuppressWarnings("unchecked") private final V internalGet(Object k) {
1101	>	int h = spread(k.hashCode());
1102	>	retry: for (Node<V>[] tab = table; tab != null;) {
1103	>	Node<V> e; Object ek; V ev; int eh; // locals to read fields once
1104	>	for (e = tabAt(tab, (tab.length - 1) & h); e != null; e = e.next) {
1105	>	if ((eh = e.hash) < 0) {
1106	>	if ((ek = e.key) instanceof TreeBin)  // search TreeBin
1107	>	return ((TreeBin<V>)ek).getValue(h, k);
1108	>	else {                      // restart with new table
1109	>	tab = (Node<V>[])ek;
1110	>	continue retry;
1111	>	}
1112	>	}
1113	>	else if (eh == h && (ev = e.val) != null &&
1114	>	((ek = e.key) == k || k.equals(ek)))
1115	>	return ev;
1116	>	}
1117	>	break;
1118		}
1119	+	return null;
1120	+	}
1121
1122	<	/**
1123	<	* Sets table to new HashEntry array.
1124	<	* Call only while holding lock or in constructor.
1125	<	*/
1126	<	void setTable(HashEntry<K,V>[] newTable) {
1127	<	threshold = (int)(newTable.length * loadFactor);
1128	<	table = newTable;
1122	>	/**
1123	>	* Implementation for the four public remove/replace methods:
1124	>	* Replaces node value with v, conditional upon match of cv if
1125	>	* non-null.  If resulting value is null, delete.
1126	>	*/
1127	>	@SuppressWarnings("unchecked") private final V internalReplace
1128	>	(Object k, V v, Object cv) {
1129	>	int h = spread(k.hashCode());
1130	>	V oldVal = null;
1131	>	for (Node<V>[] tab = table;;) {
1132	>	Node<V> f; int i, fh; Object fk;
1133	>	if (tab == null ||
1134	>	(f = tabAt(tab, i = (tab.length - 1) & h)) == null)
1135	>	break;
1136	>	else if ((fh = f.hash) < 0) {
1137	>	if ((fk = f.key) instanceof TreeBin) {
1138	>	TreeBin<V> t = (TreeBin<V>)fk;
1139	>	boolean validated = false;
1140	>	boolean deleted = false;
1141	>	t.acquire(0);
1142	>	try {
1143	>	if (tabAt(tab, i) == f) {
1144	>	validated = true;
1145	>	TreeNode<V> p = t.getTreeNode(h, k, t.root);
1146	>	if (p != null) {
1147	>	V pv = p.val;
1148	>	if (cv == null || cv == pv || cv.equals(pv)) {
1149	>	oldVal = pv;
1150	>	if ((p.val = v) == null) {
1151	>	deleted = true;
1152	>	t.deleteTreeNode(p);
1153	>	}
1154	>	}
1155	>	}
1156	>	}
1157	>	} finally {
1158	>	t.release(0);
1159	>	}
1160	>	if (validated) {
1161	>	if (deleted)
1162	>	addCount(-1L, -1);
1163	>	break;
1164	>	}
1165	>	}
1166	>	else
1167	>	tab = (Node<V>[])fk;
1168	>	}
1169	>	else if (fh != h && f.next == null) // precheck
1170	>	break;                          // rules out possible existence
1171	>	else {
1172	>	boolean validated = false;
1173	>	boolean deleted = false;
1174	>	synchronized (f) {
1175	>	if (tabAt(tab, i) == f) {
1176	>	validated = true;
1177	>	for (Node<V> e = f, pred = null;;) {
1178	>	Object ek; V ev;
1179	>	if (e.hash == h &&
1180	>	((ev = e.val) != null) &&
1181	>	((ek = e.key) == k || k.equals(ek))) {
1182	>	if (cv == null || cv == ev || cv.equals(ev)) {
1183	>	oldVal = ev;
1184	>	if ((e.val = v) == null) {
1185	>	deleted = true;
1186	>	Node<V> en = e.next;
1187	>	if (pred != null)
1188	>	pred.next = en;
1189	>	else
1190	>	setTabAt(tab, i, en);
1191	>	}
1192	>	}
1193	>	break;
1194	>	}
1195	>	pred = e;
1196	>	if ((e = e.next) == null)
1197	>	break;
1198	>	}
1199	>	}
1200	>	}
1201	>	if (validated) {
1202	>	if (deleted)
1203	>	addCount(-1L, -1);
1204	>	break;
1205	>	}
1206	>	}
1207		}
1208	+	return oldVal;
1209	+	}
1210
1211	<	/**
1212	<	* Returns properly casted first entry of bin for given hash.
1213	<	*/
1214	<	HashEntry<K,V> getFirst(int hash) {
1215	<	HashEntry<K,V>[] tab = table;
1216	<	return tab[hash & (tab.length - 1)];
1211	>	/*
1212	>	* Internal versions of insertion methods
1213	>	* All have the same basic structure as the first (internalPut):
1214	>	*  1. If table uninitialized, create
1215	>	*  2. If bin empty, try to CAS new node
1216	>	*  3. If bin stale, use new table
1217	>	*  4. if bin converted to TreeBin, validate and relay to TreeBin methods
1218	>	*  5. Lock and validate; if valid, scan and add or update
1219	>	*
1220	>	* The putAll method differs mainly in attempting to pre-allocate
1221	>	* enough table space, and also more lazily performs count updates
1222	>	* and checks.
1223	>	*
1224	>	* Most of the function-accepting methods can't be factored nicely
1225	>	* because they require different functional forms, so instead
1226	>	* sprawl out similar mechanics.
1227	>	*/
1228	>
1229	>	/** Implementation for put and putIfAbsent */
1230	>	@SuppressWarnings("unchecked") private final V internalPut
1231	>	(K k, V v, boolean onlyIfAbsent) {
1232	>	if (k == null || v == null) throw new NullPointerException();
1233	>	int h = spread(k.hashCode());
1234	>	int len = 0;
1235	>	for (Node<V>[] tab = table;;) {
1236	>	int i, fh; Node<V> f; Object fk; V fv;
1237	>	if (tab == null)
1238	>	tab = initTable();
1239	>	else if ((f = tabAt(tab, i = (tab.length - 1) & h)) == null) {
1240	>	if (casTabAt(tab, i, null, new Node<V>(h, k, v, null)))
1241	>	break;                   // no lock when adding to empty bin
1242	>	}
1243	>	else if ((fh = f.hash) < 0) {
1244	>	if ((fk = f.key) instanceof TreeBin) {
1245	>	TreeBin<V> t = (TreeBin<V>)fk;
1246	>	V oldVal = null;
1247	>	t.acquire(0);
1248	>	try {
1249	>	if (tabAt(tab, i) == f) {
1250	>	len = 2;
1251	>	TreeNode<V> p = t.putTreeNode(h, k, v);
1252	>	if (p != null) {
1253	>	oldVal = p.val;
1254	>	if (!onlyIfAbsent)
1255	>	p.val = v;
1256	>	}
1257	>	}
1258	>	} finally {
1259	>	t.release(0);
1260	>	}
1261	>	if (len != 0) {
1262	>	if (oldVal != null)
1263	>	return oldVal;
1264	>	break;
1265	>	}
1266	>	}
1267	>	else
1268	>	tab = (Node<V>[])fk;
1269	>	}
1270	>	else if (onlyIfAbsent && fh == h && (fv = f.val) != null &&
1271	>	((fk = f.key) == k || k.equals(fk))) // peek while nearby
1272	>	return fv;
1273	>	else {
1274	>	V oldVal = null;
1275	>	synchronized (f) {
1276	>	if (tabAt(tab, i) == f) {
1277	>	len = 1;
1278	>	for (Node<V> e = f;; ++len) {
1279	>	Object ek; V ev;
1280	>	if (e.hash == h &&
1281	>	(ev = e.val) != null &&
1282	>	((ek = e.key) == k || k.equals(ek))) {
1283	>	oldVal = ev;
1284	>	if (!onlyIfAbsent)
1285	>	e.val = v;
1286	>	break;
1287	>	}
1288	>	Node<V> last = e;
1289	>	if ((e = e.next) == null) {
1290	>	last.next = new Node<V>(h, k, v, null);
1291	>	if (len >= TREE_THRESHOLD)
1292	>	replaceWithTreeBin(tab, i, k);
1293	>	break;
1294	>	}
1295	>	}
1296	>	}
1297	>	}
1298	>	if (len != 0) {
1299	>	if (oldVal != null)
1300	>	return oldVal;
1301	>	break;
1302	>	}
1303	>	}
1304		}
1305	+	addCount(1L, len);
1306	+	return null;
1307	+	}
1308
1309	<	/**
1310	<	* Reads value field of an entry under lock. Called if value
1311	<	* field ever appears to be null. This is possible only if a
1312	<	* compiler happens to reorder a HashEntry initialization with
1313	<	* its table assignment, which is legal under memory model
1314	<	* but is not known to ever occur.
1315	<	*/
1316	<	V readValueUnderLock(HashEntry<K,V> e) {
1317	<	lock();
1318	<	try {
1319	<	return e.value;
1320	<	} finally {
1321	<	unlock();
1309	>	/** Implementation for computeIfAbsent */
1310	>	@SuppressWarnings("unchecked") private final V internalComputeIfAbsent
1311	>	(K k, Function<? super K, ? extends V> mf) {
1312	>	if (k == null || mf == null)
1313	>	throw new NullPointerException();
1314	>	int h = spread(k.hashCode());
1315	>	V val = null;
1316	>	int len = 0;
1317	>	for (Node<V>[] tab = table;;) {
1318	>	Node<V> f; int i; Object fk;
1319	>	if (tab == null)
1320	>	tab = initTable();
1321	>	else if ((f = tabAt(tab, i = (tab.length - 1) & h)) == null) {
1322	>	Node<V> node = new Node<V>(h, k, null, null);
1323	>	synchronized (node) {
1324	>	if (casTabAt(tab, i, null, node)) {
1325	>	len = 1;
1326	>	try {
1327	>	if ((val = mf.apply(k)) != null)
1328	>	node.val = val;
1329	>	} finally {
1330	>	if (val == null)
1331	>	setTabAt(tab, i, null);
1332	>	}
1333	>	}
1334	>	}
1335	>	if (len != 0)
1336	>	break;
1337	>	}
1338	>	else if (f.hash < 0) {
1339	>	if ((fk = f.key) instanceof TreeBin) {
1340	>	TreeBin<V> t = (TreeBin<V>)fk;
1341	>	boolean added = false;
1342	>	t.acquire(0);
1343	>	try {
1344	>	if (tabAt(tab, i) == f) {
1345	>	len = 1;
1346	>	TreeNode<V> p = t.getTreeNode(h, k, t.root);
1347	>	if (p != null)
1348	>	val = p.val;
1349	>	else if ((val = mf.apply(k)) != null) {
1350	>	added = true;
1351	>	len = 2;
1352	>	t.putTreeNode(h, k, val);
1353	>	}
1354	>	}
1355	>	} finally {
1356	>	t.release(0);
1357	>	}
1358	>	if (len != 0) {
1359	>	if (!added)
1360	>	return val;
1361	>	break;
1362	>	}
1363	>	}
1364	>	else
1365	>	tab = (Node<V>[])fk;
1366	>	}
1367	>	else {
1368	>	for (Node<V> e = f; e != null; e = e.next) { // prescan
1369	>	Object ek; V ev;
1370	>	if (e.hash == h && (ev = e.val) != null &&
1371	>	((ek = e.key) == k || k.equals(ek)))
1372	>	return ev;
1373	>	}
1374	>	boolean added = false;
1375	>	synchronized (f) {
1376	>	if (tabAt(tab, i) == f) {
1377	>	len = 1;
1378	>	for (Node<V> e = f;; ++len) {
1379	>	Object ek; V ev;
1380	>	if (e.hash == h &&
1381	>	(ev = e.val) != null &&
1382	>	((ek = e.key) == k || k.equals(ek))) {
1383	>	val = ev;
1384	>	break;
1385	>	}
1386	>	Node<V> last = e;
1387	>	if ((e = e.next) == null) {
1388	>	if ((val = mf.apply(k)) != null) {
1389	>	added = true;
1390	>	last.next = new Node<V>(h, k, val, null);
1391	>	if (len >= TREE_THRESHOLD)
1392	>	replaceWithTreeBin(tab, i, k);
1393	>	}
1394	>	break;
1395	>	}
1396	>	}
1397	>	}
1398	>	}
1399	>	if (len != 0) {
1400	>	if (!added)
1401	>	return val;
1402	>	break;
1403	>	}
1404		}
1405		}
1406	+	if (val != null)
1407	+	addCount(1L, len);
1408	+	return val;
1409	+	}
1410
1411	<	/* Specialized implementations of map methods */
1411	>	/** Implementation for compute */
1412	>	@SuppressWarnings("unchecked") private final V internalCompute
1413	>	(K k, boolean onlyIfPresent,
1414	>	BiFunction<? super K, ? super V, ? extends V> mf) {
1415	>	if (k == null || mf == null)
1416	>	throw new NullPointerException();
1417	>	int h = spread(k.hashCode());
1418	>	V val = null;
1419	>	int delta = 0;
1420	>	int len = 0;
1421	>	for (Node<V>[] tab = table;;) {
1422	>	Node<V> f; int i, fh; Object fk;
1423	>	if (tab == null)
1424	>	tab = initTable();
1425	>	else if ((f = tabAt(tab, i = (tab.length - 1) & h)) == null) {
1426	>	if (onlyIfPresent)
1427	>	break;
1428	>	Node<V> node = new Node<V>(h, k, null, null);
1429	>	synchronized (node) {
1430	>	if (casTabAt(tab, i, null, node)) {
1431	>	try {
1432	>	len = 1;
1433	>	if ((val = mf.apply(k, null)) != null) {
1434	>	node.val = val;
1435	>	delta = 1;
1436	>	}
1437	>	} finally {
1438	>	if (delta == 0)
1439	>	setTabAt(tab, i, null);
1440	>	}
1441	>	}
1442	>	}
1443	>	if (len != 0)
1444	>	break;
1445	>	}
1446	>	else if ((fh = f.hash) < 0) {
1447	>	if ((fk = f.key) instanceof TreeBin) {
1448	>	TreeBin<V> t = (TreeBin<V>)fk;
1449	>	t.acquire(0);
1450	>	try {
1451	>	if (tabAt(tab, i) == f) {
1452	>	len = 1;
1453	>	TreeNode<V> p = t.getTreeNode(h, k, t.root);
1454	>	if (p == null && onlyIfPresent)
1455	>	break;
1456	>	V pv = (p == null) ? null : p.val;
1457	>	if ((val = mf.apply(k, pv)) != null) {
1458	>	if (p != null)
1459	>	p.val = val;
1460	>	else {
1461	>	len = 2;
1462	>	delta = 1;
1463	>	t.putTreeNode(h, k, val);
1464	>	}
1465	>	}
1466	>	else if (p != null) {
1467	>	delta = -1;
1468	>	t.deleteTreeNode(p);
1469	>	}
1470	>	}
1471	>	} finally {
1472	>	t.release(0);
1473	>	}
1474	>	if (len != 0)
1475	>	break;
1476	>	}
1477	>	else
1478	>	tab = (Node<V>[])fk;
1479	>	}
1480	>	else {
1481	>	synchronized (f) {
1482	>	if (tabAt(tab, i) == f) {
1483	>	len = 1;
1484	>	for (Node<V> e = f, pred = null;; ++len) {
1485	>	Object ek; V ev;
1486	>	if (e.hash == h &&
1487	>	(ev = e.val) != null &&
1488	>	((ek = e.key) == k || k.equals(ek))) {
1489	>	val = mf.apply(k, ev);
1490	>	if (val != null)
1491	>	e.val = val;
1492	>	else {
1493	>	delta = -1;
1494	>	Node<V> en = e.next;
1495	>	if (pred != null)
1496	>	pred.next = en;
1497	>	else
1498	>	setTabAt(tab, i, en);
1499	>	}
1500	>	break;
1501	>	}
1502	>	pred = e;
1503	>	if ((e = e.next) == null) {
1504	>	if (!onlyIfPresent &&
1505	>	(val = mf.apply(k, null)) != null) {
1506	>	pred.next = new Node<V>(h, k, val, null);
1507	>	delta = 1;
1508	>	if (len >= TREE_THRESHOLD)
1509	>	replaceWithTreeBin(tab, i, k);
1510	>	}
1511	>	break;
1512	>	}
1513	>	}
1514	>	}
1515	>	}
1516	>	if (len != 0)
1517	>	break;
1518	>	}
1519	>	}
1520	>	if (delta != 0)
1521	>	addCount((long)delta, len);
1522	>	return val;
1523	>	}
1524
1525	<	V get(Object key, int hash) {
1526	<	if (count != 0) { // read-volatile
1527	<	HashEntry<K,V> e = getFirst(hash);
1528	<	while (e != null) {
1529	<	if (e.hash == hash && key.equals(e.key)) {
1530	<	V v = e.value;
1531	<	if (v != null)
1532	<	return v;
1533	<	return readValueUnderLock(e); // recheck
1525	>	/** Implementation for merge */
1526	>	@SuppressWarnings("unchecked") private final V internalMerge
1527	>	(K k, V v, BiFunction<? super V, ? super V, ? extends V> mf) {
1528	>	if (k == null || v == null || mf == null)
1529	>	throw new NullPointerException();
1530	>	int h = spread(k.hashCode());
1531	>	V val = null;
1532	>	int delta = 0;
1533	>	int len = 0;
1534	>	for (Node<V>[] tab = table;;) {
1535	>	int i; Node<V> f; Object fk; V fv;
1536	>	if (tab == null)
1537	>	tab = initTable();
1538	>	else if ((f = tabAt(tab, i = (tab.length - 1) & h)) == null) {
1539	>	if (casTabAt(tab, i, null, new Node<V>(h, k, v, null))) {
1540	>	delta = 1;
1541	>	val = v;
1542	>	break;
1543	>	}
1544	>	}
1545	>	else if (f.hash < 0) {
1546	>	if ((fk = f.key) instanceof TreeBin) {
1547	>	TreeBin<V> t = (TreeBin<V>)fk;
1548	>	t.acquire(0);
1549	>	try {
1550	>	if (tabAt(tab, i) == f) {
1551	>	len = 1;
1552	>	TreeNode<V> p = t.getTreeNode(h, k, t.root);
1553	>	val = (p == null) ? v : mf.apply(p.val, v);
1554	>	if (val != null) {
1555	>	if (p != null)
1556	>	p.val = val;
1557	>	else {
1558	>	len = 2;
1559	>	delta = 1;
1560	>	t.putTreeNode(h, k, val);
1561	>	}
1562	>	}
1563	>	else if (p != null) {
1564	>	delta = -1;
1565	>	t.deleteTreeNode(p);
1566	>	}
1567	>	}
1568	>	} finally {
1569	>	t.release(0);
1570		}
1571	<	e = e.next;
1571	>	if (len != 0)
1572	>	break;
1573		}
1574	+	else
1575	+	tab = (Node<V>[])fk;
1576	+	}
1577	+	else {
1578	+	synchronized (f) {
1579	+	if (tabAt(tab, i) == f) {
1580	+	len = 1;
1581	+	for (Node<V> e = f, pred = null;; ++len) {
1582	+	Object ek; V ev;
1583	+	if (e.hash == h &&
1584	+	(ev = e.val) != null &&
1585	+	((ek = e.key) == k || k.equals(ek))) {
1586	+	val = mf.apply(ev, v);
1587	+	if (val != null)
1588	+	e.val = val;
1589	+	else {
1590	+	delta = -1;
1591	+	Node<V> en = e.next;
1592	+	if (pred != null)
1593	+	pred.next = en;
1594	+	else
1595	+	setTabAt(tab, i, en);
1596	+	}
1597	+	break;
1598	+	}
1599	+	pred = e;
1600	+	if ((e = e.next) == null) {
1601	+	val = v;
1602	+	pred.next = new Node<V>(h, k, val, null);
1603	+	delta = 1;
1604	+	if (len >= TREE_THRESHOLD)
1605	+	replaceWithTreeBin(tab, i, k);
1606	+	break;
1607	+	}
1608	+	}
1609	+	}
1610	+	}
1611	+	if (len != 0)
1612	+	break;
1613		}
343	–	return null;
1614		}
1615	+	if (delta != 0)
1616	+	addCount((long)delta, len);
1617	+	return val;
1618	+	}
1619
1620	<	boolean containsKey(Object key, int hash) {
1621	<	if (count != 0) { // read-volatile
1622	<	HashEntry<K,V> e = getFirst(hash);
1623	<	while (e != null) {
1624	<	if (e.hash == hash && key.equals(e.key))
1625	<	return true;
1626	<	e = e.next;
1620	>	/** Implementation for putAll */
1621	>	@SuppressWarnings("unchecked") private final void internalPutAll
1622	>	(Map<? extends K, ? extends V> m) {
1623	>	tryPresize(m.size());
1624	>	long delta = 0L;     // number of uncommitted additions
1625	>	boolean npe = false; // to throw exception on exit for nulls
1626	>	try {                // to clean up counts on other exceptions
1627	>	for (Map.Entry<?, ? extends V> entry : m.entrySet()) {
1628	>	Object k; V v;
1629	>	if (entry == null || (k = entry.getKey()) == null ||
1630	>	(v = entry.getValue()) == null) {
1631	>	npe = true;
1632	>	break;
1633	>	}
1634	>	int h = spread(k.hashCode());
1635	>	for (Node<V>[] tab = table;;) {
1636	>	int i; Node<V> f; int fh; Object fk;
1637	>	if (tab == null)
1638	>	tab = initTable();
1639	>	else if ((f = tabAt(tab, i = (tab.length - 1) & h)) == null){
1640	>	if (casTabAt(tab, i, null, new Node<V>(h, k, v, null))) {
1641	>	++delta;
1642	>	break;
1643	>	}
1644	>	}
1645	>	else if ((fh = f.hash) < 0) {
1646	>	if ((fk = f.key) instanceof TreeBin) {
1647	>	TreeBin<V> t = (TreeBin<V>)fk;
1648	>	boolean validated = false;
1649	>	t.acquire(0);
1650	>	try {
1651	>	if (tabAt(tab, i) == f) {
1652	>	validated = true;
1653	>	TreeNode<V> p = t.getTreeNode(h, k, t.root);
1654	>	if (p != null)
1655	>	p.val = v;
1656	>	else {
1657	>	t.putTreeNode(h, k, v);
1658	>	++delta;
1659	>	}
1660	>	}
1661	>	} finally {
1662	>	t.release(0);
1663	>	}
1664	>	if (validated)
1665	>	break;
1666	>	}
1667	>	else
1668	>	tab = (Node<V>[])fk;
1669	>	}
1670	>	else {
1671	>	int len = 0;
1672	>	synchronized (f) {
1673	>	if (tabAt(tab, i) == f) {
1674	>	len = 1;
1675	>	for (Node<V> e = f;; ++len) {
1676	>	Object ek; V ev;
1677	>	if (e.hash == h &&
1678	>	(ev = e.val) != null &&
1679	>	((ek = e.key) == k || k.equals(ek))) {
1680	>	e.val = v;
1681	>	break;
1682	>	}
1683	>	Node<V> last = e;
1684	>	if ((e = e.next) == null) {
1685	>	++delta;
1686	>	last.next = new Node<V>(h, k, v, null);
1687	>	if (len >= TREE_THRESHOLD)
1688	>	replaceWithTreeBin(tab, i, k);
1689	>	break;
1690	>	}
1691	>	}
1692	>	}
1693	>	}
1694	>	if (len != 0) {
1695	>	if (len > 1) {
1696	>	addCount(delta, len);
1697	>	delta = 0L;
1698	>	}
1699	>	break;
1700	>	}
1701	>	}
1702		}
1703		}
1704	<	return false;
1704	>	} finally {
1705	>	if (delta != 0L)
1706	>	addCount(delta, 2);
1707		}
1708	+	if (npe)
1709	+	throw new NullPointerException();
1710	+	}
1711
1712	<	boolean containsValue(Object value) {
1713	<	if (count != 0) { // read-volatile
1714	<	HashEntry<K,V>[] tab = table;
1715	<	int len = tab.length;
1716	<	for (int i = 0 ; i < len; i++) {
1717	<	for (HashEntry<K,V> e = tab[i]; e != null; e = e.next) {
1718	<	V v = e.value;
1719	<	if (v == null) // recheck
1720	<	v = readValueUnderLock(e);
1721	<	if (value.equals(v))
1722	<	return true;
1712	>	/**
1713	>	* Implementation for clear. Steps through each bin, removing all
1714	>	* nodes.
1715	>	*/
1716	>	@SuppressWarnings("unchecked") private final void internalClear() {
1717	>	long delta = 0L; // negative number of deletions
1718	>	int i = 0;
1719	>	Node<V>[] tab = table;
1720	>	while (tab != null && i < tab.length) {
1721	>	Node<V> f = tabAt(tab, i);
1722	>	if (f == null)
1723	>	++i;
1724	>	else if (f.hash < 0) {
1725	>	Object fk;
1726	>	if ((fk = f.key) instanceof TreeBin) {
1727	>	TreeBin<V> t = (TreeBin<V>)fk;
1728	>	t.acquire(0);
1729	>	try {
1730	>	if (tabAt(tab, i) == f) {
1731	>	for (Node<V> p = t.first; p != null; p = p.next) {
1732	>	if (p.val != null) { // (currently always true)
1733	>	p.val = null;
1734	>	--delta;
1735	>	}
1736	>	}
1737	>	t.first = null;
1738	>	t.root = null;
1739	>	++i;
1740	>	}
1741	>	} finally {
1742	>	t.release(0);
1743	>	}
1744	>	}
1745	>	else
1746	>	tab = (Node<V>[])fk;
1747	>	}
1748	>	else {
1749	>	synchronized (f) {
1750	>	if (tabAt(tab, i) == f) {
1751	>	for (Node<V> e = f; e != null; e = e.next) {
1752	>	if (e.val != null) {  // (currently always true)
1753	>	e.val = null;
1754	>	--delta;
1755	>	}
1756	>	}
1757	>	setTabAt(tab, i, null);
1758	>	++i;
1759		}
1760		}
1761		}
372	–	return false;
1762		}
1763	+	if (delta != 0L)
1764	+	addCount(delta, -1);
1765	+	}
1766
1767	<	boolean replace(K key, int hash, V oldValue, V newValue) {
1768	<	lock();
1769	<	try {
1770	<	HashEntry<K,V> e = getFirst(hash);
1771	<	while (e != null && (e.hash != hash || !key.equals(e.key)))
1772	<	e = e.next;
1767	>	/* ---------------- Table Initialization and Resizing -------------- */
1768	>
1769	>	/**
1770	>	* Returns a power of two table size for the given desired capacity.
1771	>	* See Hackers Delight, sec 3.2
1772	>	*/
1773	>	private static final int tableSizeFor(int c) {
1774	>	int n = c - 1;
1775	>	n |= n >>> 1;
1776	>	n |= n >>> 2;
1777	>	n |= n >>> 4;
1778	>	n |= n >>> 8;
1779	>	n |= n >>> 16;
1780	>	return (n < 0) ? 1 : (n >= MAXIMUM_CAPACITY) ? MAXIMUM_CAPACITY : n + 1;
1781	>	}
1782
1783	<	boolean replaced = false;
1784	<	if (e != null && oldValue.equals(e.value)) {
1785	<	replaced = true;
1786	<	e.value = newValue;
1783	>	/**
1784	>	* Initializes table, using the size recorded in sizeCtl.
1785	>	*/
1786	>	@SuppressWarnings("unchecked") private final Node<V>[] initTable() {
1787	>	Node<V>[] tab; int sc;
1788	>	while ((tab = table) == null) {
1789	>	if ((sc = sizeCtl) < 0)
1790	>	Thread.yield(); // lost initialization race; just spin
1791	>	else if (U.compareAndSwapInt(this, SIZECTL, sc, -1)) {
1792	>	try {
1793	>	if ((tab = table) == null) {
1794	>	int n = (sc > 0) ? sc : DEFAULT_CAPACITY;
1795	>	@SuppressWarnings("rawtypes") Node[] tb = new Node[n];
1796	>	table = tab = (Node<V>[])tb;
1797	>	sc = n - (n >>> 2);
1798	>	}
1799	>	} finally {
1800	>	sizeCtl = sc;
1801		}
1802	<	return replaced;
388	<	} finally {
389	<	unlock();
1802	>	break;
1803		}
1804		}
1805	+	return tab;
1806	+	}
1807
1808	<	V replace(K key, int hash, V newValue) {
1809	<	lock();
1810	<	try {
1811	<	HashEntry<K,V> e = getFirst(hash);
1812	<	while (e != null && (e.hash != hash || !key.equals(e.key)))
1813	<	e = e.next;
1814	<
1815	<	V oldValue = null;
1816	<	if (e != null) {
1817	<	oldValue = e.value;
1818	<	e.value = newValue;
1808	>	/**
1809	>	* Adds to count, and if table is too small and not already
1810	>	* resizing, initiates transfer. If already resizing, helps
1811	>	* perform transfer if work is available.  Rechecks occupancy
1812	>	* after a transfer to see if another resize is already needed
1813	>	* because resizings are lagging additions.
1814	>	*
1815	>	* @param x the count to add
1816	>	* @param check if <0, don't check resize, if <= 1 only check if uncontended
1817	>	*/
1818	>	private final void addCount(long x, int check) {
1819	>	Cell[] as; long b, s;
1820	>	if ((as = counterCells) != null ||
1821	>	!U.compareAndSwapLong(this, BASECOUNT, b = baseCount, s = b + x)) {
1822	>	Cell a; long v; int m;
1823	>	boolean uncontended = true;
1824	>	if (as == null || (m = as.length - 1) < 0 ||
1825	>	(a = as[ThreadLocalRandom.getProbe() & m]) == null ||
1826	>	!(uncontended =
1827	>	U.compareAndSwapLong(a, CELLVALUE, v = a.value, v + x))) {
1828	>	fullAddCount(x, uncontended);
1829	>	return;
1830	>	}
1831	>	if (check <= 1)
1832	>	return;
1833	>	s = sumCount();
1834	>	}
1835	>	if (check >= 0) {
1836	>	Node<V>[] tab, nt; int sc;
1837	>	while (s >= (long)(sc = sizeCtl) && (tab = table) != null &&
1838	>	tab.length < MAXIMUM_CAPACITY) {
1839	>	if (sc < 0) {
1840	>	if (sc == -1 || transferIndex <= transferOrigin ||
1841	>	(nt = nextTable) == null)
1842	>	break;
1843	>	if (U.compareAndSwapInt(this, SIZECTL, sc, sc - 1))
1844	>	transfer(tab, nt);
1845		}
1846	<	return oldValue;
1847	<	} finally {
1848	<	unlock();
1846	>	else if (U.compareAndSwapInt(this, SIZECTL, sc, -2))
1847	>	transfer(tab, null);
1848	>	s = sumCount();
1849		}
1850		}
1851	+	}
1852
1853	+	/**
1854	+	* Tries to presize table to accommodate the given number of elements.
1855	+	*
1856	+	* @param size number of elements (doesn't need to be perfectly accurate)
1857	+	*/
1858	+	@SuppressWarnings("unchecked") private final void tryPresize(int size) {
1859	+	int c = (size >= (MAXIMUM_CAPACITY >>> 1)) ? MAXIMUM_CAPACITY :
1860	+	tableSizeFor(size + (size >>> 1) + 1);
1861	+	int sc;
1862	+	while ((sc = sizeCtl) >= 0) {
1863	+	Node<V>[] tab = table; int n;
1864	+	if (tab == null || (n = tab.length) == 0) {
1865	+	n = (sc > c) ? sc : c;
1866	+	if (U.compareAndSwapInt(this, SIZECTL, sc, -1)) {
1867	+	try {
1868	+	if (table == tab) {
1869	+	@SuppressWarnings("rawtypes") Node[] tb = new Node[n];
1870	+	table = (Node<V>[])tb;
1871	+	sc = n - (n >>> 2);
1872	+	}
1873	+	} finally {
1874	+	sizeCtl = sc;
1875	+	}
1876	+	}
1877	+	}
1878	+	else if (c <= sc || n >= MAXIMUM_CAPACITY)
1879	+	break;
1880	+	else if (tab == table &&
1881	+	U.compareAndSwapInt(this, SIZECTL, sc, -2))
1882	+	transfer(tab, null);
1883	+	}
1884	+	}
1885
1886	<	V put(K key, int hash, V value, boolean onlyIfAbsent) {
1887	<	lock();
1886	>	/**
1887	>	* Moves and/or copies the nodes in each bin to new table. See
1888	>	* above for explanation.
1889	>	*/
1890	>	@SuppressWarnings("unchecked") private final void transfer
1891	>	(Node<V>[] tab, Node<V>[] nextTab) {
1892	>	int n = tab.length, stride;
1893	>	if ((stride = (NCPU > 1) ? (n >>> 3) / NCPU : n) < MIN_TRANSFER_STRIDE)
1894	>	stride = MIN_TRANSFER_STRIDE; // subdivide range
1895	>	if (nextTab == null) {            // initiating
1896		try {
1897	<	int c = count;
1898	<	if (c++ > threshold) // ensure capacity
1899	<	rehash();
1900	<	HashEntry<K,V>[] tab = table;
1901	<	int index = hash & (tab.length - 1);
1902	<	HashEntry<K,V> first = tab[index];
1903	<	HashEntry<K,V> e = first;
1904	<	while (e != null && (e.hash != hash || !key.equals(e.key)))
1905	<	e = e.next;
1906	<
1907	<	V oldValue;
1908	<	if (e != null) {
1909	<	oldValue = e.value;
1910	<	if (!onlyIfAbsent)
1911	<	e.value = value;
1897	>	@SuppressWarnings("rawtypes") Node[] tb = new Node[n << 1];
1898	>	nextTab = (Node<V>[])tb;
1899	>	} catch (Throwable ex) {      // try to cope with OOME
1900	>	sizeCtl = Integer.MAX_VALUE;
1901	>	return;
1902	>	}
1903	>	nextTable = nextTab;
1904	>	transferOrigin = n;
1905	>	transferIndex = n;
1906	>	Node<V> rev = new Node<V>(MOVED, tab, null, null);
1907	>	for (int k = n; k > 0;) {    // progressively reveal ready slots
1908	>	int nextk = (k > stride) ? k - stride : 0;
1909	>	for (int m = nextk; m < k; ++m)
1910	>	nextTab[m] = rev;
1911	>	for (int m = n + nextk; m < n + k; ++m)
1912	>	nextTab[m] = rev;
1913	>	U.putOrderedInt(this, TRANSFERORIGIN, k = nextk);
1914	>	}
1915	>	}
1916	>	int nextn = nextTab.length;
1917	>	Node<V> fwd = new Node<V>(MOVED, nextTab, null, null);
1918	>	boolean advance = true;
1919	>	for (int i = 0, bound = 0;;) {
1920	>	int nextIndex, nextBound; Node<V> f; Object fk;
1921	>	while (advance) {
1922	>	if (--i >= bound)
1923	>	advance = false;
1924	>	else if ((nextIndex = transferIndex) <= transferOrigin) {
1925	>	i = -1;
1926	>	advance = false;
1927		}
1928	<	else {
1929	<	oldValue = null;
1930	<	++modCount;
1931	<	tab[index] = new HashEntry<K,V>(key, hash, first, value);
1932	<	count = c; // write-volatile
1928	>	else if (U.compareAndSwapInt
1929	>	(this, TRANSFERINDEX, nextIndex,
1930	>	nextBound = (nextIndex > stride ?
1931	>	nextIndex - stride : 0))) {
1932	>	bound = nextBound;
1933	>	i = nextIndex - 1;
1934	>	advance = false;
1935	>	}
1936	>	}
1937	>	if (i < 0 || i >= n || i + n >= nextn) {
1938	>	for (int sc;;) {
1939	>	if (U.compareAndSwapInt(this, SIZECTL, sc = sizeCtl, ++sc)) {
1940	>	if (sc == -1) {
1941	>	nextTable = null;
1942	>	table = nextTab;
1943	>	sizeCtl = (n << 1) - (n >>> 1);
1944	>	}
1945	>	return;
1946	>	}
1947		}
437	–	return oldValue;
438	–	} finally {
439	–	unlock();
1948		}
1949	+	else if ((f = tabAt(tab, i)) == null) {
1950	+	if (casTabAt(tab, i, null, fwd)) {
1951	+	setTabAt(nextTab, i, null);
1952	+	setTabAt(nextTab, i + n, null);
1953	+	advance = true;
1954	+	}
1955	+	}
1956	+	else if (f.hash >= 0) {
1957	+	synchronized (f) {
1958	+	if (tabAt(tab, i) == f) {
1959	+	int runBit = f.hash & n;
1960	+	Node<V> lastRun = f, lo = null, hi = null;
1961	+	for (Node<V> p = f.next; p != null; p = p.next) {
1962	+	int b = p.hash & n;
1963	+	if (b != runBit) {
1964	+	runBit = b;
1965	+	lastRun = p;
1966	+	}
1967	+	}
1968	+	if (runBit == 0)
1969	+	lo = lastRun;
1970	+	else
1971	+	hi = lastRun;
1972	+	for (Node<V> p = f; p != lastRun; p = p.next) {
1973	+	int ph = p.hash;
1974	+	Object pk = p.key; V pv = p.val;
1975	+	if ((ph & n) == 0)
1976	+	lo = new Node<V>(ph, pk, pv, lo);
1977	+	else
1978	+	hi = new Node<V>(ph, pk, pv, hi);
1979	+	}
1980	+	setTabAt(nextTab, i, lo);
1981	+	setTabAt(nextTab, i + n, hi);
1982	+	setTabAt(tab, i, fwd);
1983	+	advance = true;
1984	+	}
1985	+	}
1986	+	}
1987	+	else if ((fk = f.key) instanceof TreeBin) {
1988	+	TreeBin<V> t = (TreeBin<V>)fk;
1989	+	t.acquire(0);
1990	+	try {
1991	+	if (tabAt(tab, i) == f) {
1992	+	TreeBin<V> lt = new TreeBin<V>();
1993	+	TreeBin<V> ht = new TreeBin<V>();
1994	+	int lc = 0, hc = 0;
1995	+	for (Node<V> e = t.first; e != null; e = e.next) {
1996	+	int h = e.hash;
1997	+	Object k = e.key; V v = e.val;
1998	+	if ((h & n) == 0) {
1999	+	++lc;
2000	+	lt.putTreeNode(h, k, v);
2001	+	}
2002	+	else {
2003	+	++hc;
2004	+	ht.putTreeNode(h, k, v);
2005	+	}
2006	+	}
2007	+	Node<V> ln, hn; // throw away trees if too small
2008	+	if (lc < TREE_THRESHOLD) {
2009	+	ln = null;
2010	+	for (Node<V> p = lt.first; p != null; p = p.next)
2011	+	ln = new Node<V>(p.hash, p.key, p.val, ln);
2012	+	}
2013	+	else
2014	+	ln = new Node<V>(MOVED, lt, null, null);
2015	+	setTabAt(nextTab, i, ln);
2016	+	if (hc < TREE_THRESHOLD) {
2017	+	hn = null;
2018	+	for (Node<V> p = ht.first; p != null; p = p.next)
2019	+	hn = new Node<V>(p.hash, p.key, p.val, hn);
2020	+	}
2021	+	else
2022	+	hn = new Node<V>(MOVED, ht, null, null);
2023	+	setTabAt(nextTab, i + n, hn);
2024	+	setTabAt(tab, i, fwd);
2025	+	advance = true;
2026	+	}
2027	+	} finally {
2028	+	t.release(0);
2029	+	}
2030	+	}
2031	+	else
2032	+	advance = true; // already processed
2033		}
2034	+	}
2035
2036	<	void rehash() {
444	<	HashEntry<K,V>[] oldTable = table;
445	<	int oldCapacity = oldTable.length;
446	<	if (oldCapacity >= MAXIMUM_CAPACITY)
447	<	return;
2036	>	/* ---------------- Counter support -------------- */
2037
2038	<	/*
2039	<	* Reclassify nodes in each list to new Map.  Because we are
2040	<	* using power-of-two expansion, the elements from each bin
2041	<	* must either stay at same index, or move with a power of two
2042	<	* offset. We eliminate unnecessary node creation by catching
2043	<	* cases where old nodes can be reused because their next
2044	<	* fields won't change. Statistically, at the default
2045	<	* threshold, only about one-sixth of them need cloning when
2046	<	* a table doubles. The nodes they replace will be garbage
2047	<	* collectable as soon as they are no longer referenced by any
2048	<	* reader thread that may be in the midst of traversing table
460	<	* right now.
461	<	*/
462	<
463	<	HashEntry<K,V>[] newTable = HashEntry.newArray(oldCapacity<<1);
464	<	threshold = (int)(newTable.length * loadFactor);
465	<	int sizeMask = newTable.length - 1;
466	<	for (int i = 0; i < oldCapacity ; i++) {
467	<	// We need to guarantee that any existing reads of old Map can
468	<	//  proceed. So we cannot yet null out each bin.
469	<	HashEntry<K,V> e = oldTable[i];
470	<
471	<	if (e != null) {
472	<	HashEntry<K,V> next = e.next;
473	<	int idx = e.hash & sizeMask;
474	<
475	<	//  Single node on list
476	<	if (next == null)
477	<	newTable[idx] = e;
2038	>	final long sumCount() {
2039	>	Cell[] as = counterCells; Cell a;
2040	>	long sum = baseCount;
2041	>	if (as != null) {
2042	>	for (int i = 0; i < as.length; ++i) {
2043	>	if ((a = as[i]) != null)
2044	>	sum += a.value;
2045	>	}
2046	>	}
2047	>	return sum;
2048	>	}
2049
2050	<	else {
2051	<	// Reuse trailing consecutive sequence at same slot
2052	<	HashEntry<K,V> lastRun = e;
2053	<	int lastIdx = idx;
2054	<	for (HashEntry<K,V> last = next;
2055	<	last != null;
2056	<	last = last.next) {
2057	<	int k = last.hash & sizeMask;
2058	<	if (k != lastIdx) {
2059	<	lastIdx = k;
2060	<	lastRun = last;
2050	>	// See LongAdder version for explanation
2051	>	private final void fullAddCount(long x, boolean wasUncontended) {
2052	>	int h;
2053	>	if ((h = ThreadLocalRandom.getProbe()) == 0) {
2054	>	ThreadLocalRandom.localInit();      // force initialization
2055	>	h = ThreadLocalRandom.getProbe();
2056	>	wasUncontended = true;
2057	>	}
2058	>	boolean collide = false;                // True if last slot nonempty
2059	>	for (;;) {
2060	>	Cell[] as; Cell a; int n; long v;
2061	>	if ((as = counterCells) != null && (n = as.length) > 0) {
2062	>	if ((a = as[(n - 1) & h]) == null) {
2063	>	if (cellsBusy == 0) {            // Try to attach new Cell
2064	>	Cell r = new Cell(x); // Optimistic create
2065	>	if (cellsBusy == 0 &&
2066	>	U.compareAndSwapInt(this, CELLSBUSY, 0, 1)) {
2067	>	boolean created = false;
2068	>	try {               // Recheck under lock
2069	>	Cell[] rs; int m, j;
2070	>	if ((rs = counterCells) != null &&
2071	>	(m = rs.length) > 0 &&
2072	>	rs[j = (m - 1) & h] == null) {
2073	>	rs[j] = r;
2074	>	created = true;
2075	>	}
2076	>	} finally {
2077	>	cellsBusy = 0;
2078		}
2079	+	if (created)
2080	+	break;
2081	+	continue;           // Slot is now non-empty
2082	+	}
2083	+	}
2084	+	collide = false;
2085	+	}
2086	+	else if (!wasUncontended)       // CAS already known to fail
2087	+	wasUncontended = true;      // Continue after rehash
2088	+	else if (U.compareAndSwapLong(a, CELLVALUE, v = a.value, v + x))
2089	+	break;
2090	+	else if (counterCells != as || n >= NCPU)
2091	+	collide = false;            // At max size or stale
2092	+	else if (!collide)
2093	+	collide = true;
2094	+	else if (cellsBusy == 0 &&
2095	+	U.compareAndSwapInt(this, CELLSBUSY, 0, 1)) {
2096	+	try {
2097	+	if (counterCells == as) {// Expand table unless stale
2098	+	Cell[] rs = new Cell[n << 1];
2099	+	for (int i = 0; i < n; ++i)
2100	+	rs[i] = as[i];
2101	+	counterCells = rs;
2102		}
2103	<	newTable[lastIdx] = lastRun;
2103	>	} finally {
2104	>	cellsBusy = 0;
2105	>	}
2106	>	collide = false;
2107	>	continue;                   // Retry with expanded table
2108	>	}
2109	>	h = ThreadLocalRandom.advanceProbe(h);
2110	>	}
2111	>	else if (cellsBusy == 0 && counterCells == as &&
2112	>	U.compareAndSwapInt(this, CELLSBUSY, 0, 1)) {
2113	>	boolean init = false;
2114	>	try {                           // Initialize table
2115	>	if (counterCells == as) {
2116	>	Cell[] rs = new Cell[2];
2117	>	rs[h & 1] = new Cell(x);
2118	>	counterCells = rs;
2119	>	init = true;
2120	>	}
2121	>	} finally {
2122	>	cellsBusy = 0;
2123	>	}
2124	>	if (init)
2125	>	break;
2126	>	}
2127	>	else if (U.compareAndSwapLong(this, BASECOUNT, v = baseCount, v + x))
2128	>	break;                          // Fall back on using base
2129	>	}
2130	>	}
2131
2132	<	// Clone all remaining nodes
2133	<	for (HashEntry<K,V> p = e; p != lastRun; p = p.next) {
2134	<	int k = p.hash & sizeMask;
2135	<	HashEntry<K,V> n = newTable[k];
2136	<	newTable[k] = new HashEntry<K,V>(p.key, p.hash,
2137	<	n, p.value);
2132	>	/* ----------------Table Traversal -------------- */
2133	>
2134	>	/**
2135	>	* Encapsulates traversal for methods such as containsValue; also
2136	>	* serves as a base class for other iterators and bulk tasks.
2137	>	*
2138	>	* At each step, the iterator snapshots the key ("nextKey") and
2139	>	* value ("nextVal") of a valid node (i.e., one that, at point of
2140	>	* snapshot, has a non-null user value). Because val fields can
2141	>	* change (including to null, indicating deletion), field nextVal
2142	>	* might not be accurate at point of use, but still maintains the
2143	>	* weak consistency property of holding a value that was once
2144	>	* valid. To support iterator.remove, the nextKey field is not
2145	>	* updated (nulled out) when the iterator cannot advance.
2146	>	*
2147	>	* Exported iterators must track whether the iterator has advanced
2148	>	* (in hasNext vs next) (by setting/checking/nulling field
2149	>	* nextVal), and then extract key, value, or key-value pairs as
2150	>	* return values of next().
2151	>	*
2152	>	* Method advance visits once each still-valid node that was
2153	>	* reachable upon iterator construction. It might miss some that
2154	>	* were added to a bin after the bin was visited, which is OK wrt
2155	>	* consistency guarantees. Maintaining this property in the face
2156	>	* of possible ongoing resizes requires a fair amount of
2157	>	* bookkeeping state that is difficult to optimize away amidst
2158	>	* volatile accesses.  Even so, traversal maintains reasonable
2159	>	* throughput.
2160	>	*
2161	>	* Normally, iteration proceeds bin-by-bin traversing lists.
2162	>	* However, if the table has been resized, then all future steps
2163	>	* must traverse both the bin at the current index as well as at
2164	>	* (index + baseSize); and so on for further resizings. To
2165	>	* paranoically cope with potential sharing by users of iterators
2166	>	* across threads, iteration terminates if a bounds checks fails
2167	>	* for a table read.
2168	>	*
2169	>	* Methods advanceKey and advanceValue are specializations of the
2170	>	* common cases of advance, relaying to the full version
2171	>	* otherwise. The forEachKey and forEachValue methods further
2172	>	* specialize, bypassing all incremental field updates in most cases.
2173	>	*
2174	>	* This class supports both Spliterator-based traversal and
2175	>	* CountedCompleter-based bulk tasks. The same "batch" field is
2176	>	* used, but in slightly different ways, in the two cases.  For
2177	>	* Spliterators, it is a saturating (at Integer.MAX_VALUE)
2178	>	* estimate of element coverage. For CHM tasks, it is a pre-scaled
2179	>	* size that halves down to zero for leaf tasks, that is only
2180	>	* computed upon execution of the task. (Tasks can be submitted to
2181	>	* any pool, of any size, so we don't know scale factors until
2182	>	* running.)
2183	>	*
2184	>	* This class extends CountedCompleter to streamline parallel
2185	>	* iteration in bulk operations. This adds only a few fields of
2186	>	* space overhead, which is small enough in cases where it is not
2187	>	* needed to not worry about it.  Because CountedCompleter is
2188	>	* Serializable, but iterators need not be, we need to add warning
2189	>	* suppressions.
2190	>	*/
2191	>	@SuppressWarnings("serial") static class Traverser<K,V,R>
2192	>	extends CountedCompleter<R> {
2193	>	final ConcurrentHashMap<K,V> map;
2194	>	Node<V> next;        // the next entry to use
2195	>	K nextKey;           // cached key field of next
2196	>	V nextVal;           // cached val field of next
2197	>	Node<V>[] tab;       // current table; updated if resized
2198	>	int index;           // index of bin to use next
2199	>	int baseIndex;       // current index of initial table
2200	>	int baseLimit;       // index bound for initial table
2201	>	final int baseSize;  // initial table size
2202	>	int batch;           // split control
2203	>
2204	>	/** Creates iterator for all entries in the table. */
2205	>	Traverser(ConcurrentHashMap<K,V> map) {
2206	>	this.map = map;
2207	>	Node<V>[] t = this.tab = map.table;
2208	>	baseLimit = baseSize = (t == null) ? 0 : t.length;
2209	>	}
2210	>
2211	>	/** Task constructor */
2212	>	Traverser(ConcurrentHashMap<K,V> map, Traverser<K,V,?> it, int batch) {
2213	>	super(it);
2214	>	this.map = map;
2215	>	this.batch = batch; // -1 if unknown
2216	>	if (it == null) {
2217	>	Node<V>[] t = this.tab = map.table;
2218	>	baseLimit = baseSize = (t == null) ? 0 : t.length;
2219	>	}
2220	>	else { // split parent
2221	>	this.tab = it.tab;
2222	>	this.baseSize = it.baseSize;
2223	>	int hi = this.baseLimit = it.baseLimit;
2224	>	it.baseLimit = this.index = this.baseIndex =
2225	>	(hi + it.baseIndex + 1) >>> 1;
2226	>	}
2227	>	}
2228	>
2229	>	/** Spliterator constructor */
2230	>	Traverser(ConcurrentHashMap<K,V> map, Traverser<K,V,?> it) {
2231	>	super(it);
2232	>	this.map = map;
2233	>	if (it == null) {
2234	>	Node<V>[] t = this.tab = map.table;
2235	>	baseLimit = baseSize = (t == null) ? 0 : t.length;
2236	>	long n = map.sumCount();
2237	>	batch = ((n > (long)Integer.MAX_VALUE) ? Integer.MAX_VALUE :
2238	>	(int)n);
2239	>	}
2240	>	else {
2241	>	this.tab = it.tab;
2242	>	this.baseSize = it.baseSize;
2243	>	int hi = this.baseLimit = it.baseLimit;
2244	>	it.baseLimit = this.index = this.baseIndex =
2245	>	(hi + it.baseIndex + 1) >>> 1;
2246	>	this.batch = it.batch >>>= 1;
2247	>	}
2248	>	}
2249	>
2250	>	/**
2251	>	* Advances if possible, returning next valid value, or null if none.
2252	>	*/
2253	>	@SuppressWarnings("unchecked") final V advance() {
2254	>	for (Node<V> e = next;;) {
2255	>	if (e != null)                  // advance past used/skipped node
2256	>	e = next = e.next;
2257	>	while (e == null) {             // get to next non-null bin
2258	>	Node<V>[] t; int i, n;      // must use locals in checks
2259	>	if (baseIndex >= baseLimit || (t = tab) == null ||
2260	>	(n = t.length) <= (i = index) || i < 0)
2261	>	return nextVal = null;
2262	>	if ((e = next = tabAt(t, index)) != null && e.hash < 0) {
2263	>	Object ek;
2264	>	if ((ek = e.key) instanceof TreeBin)
2265	>	e = ((TreeBin<V>)ek).first;
2266	>	else {
2267	>	tab = (Node<V>[])ek;
2268	>	continue;           // restarts due to null val
2269		}
2270		}
2271	+	if ((index += baseSize) >= n)
2272	+	index = ++baseIndex;    // visit upper slots if present
2273		}
2274	+	nextKey = (K)e.key;
2275	+	if ((nextVal = e.val) != null) // skip deleted or special nodes
2276	+	return nextVal;
2277		}
504	–	table = newTable;
2278		}
2279
2280		/**
2281	<	* Remove; match on key only if value null, else match both.
2281	>	* Common case version for value traversal
2282		*/
2283	<	V remove(Object key, int hash, Object value) {
2284	<	lock();
2285	<	try {
2286	<	int c = count - 1;
2287	<	HashEntry<K,V>[] tab = table;
2288	<	int index = hash & (tab.length - 1);
2289	<	HashEntry<K,V> first = tab[index];
2290	<	HashEntry<K,V> e = first;
2291	<	while (e != null && (e.hash != hash || !key.equals(e.key)))
2292	<	e = e.next;
2293	<
2294	<	V oldValue = null;
2295	<	if (e != null) {
2296	<	V v = e.value;
2297	<	if (value == null || value.equals(v)) {
2298	<	oldValue = v;
2299	<	// All entries following removed node can stay
2300	<	// in list, but all preceding ones need to be
2301	<	// cloned.
2302	<	++modCount;
2303	<	HashEntry<K,V> newFirst = e.next;
2304	<	for (HashEntry<K,V> p = first; p != e; p = p.next)
2305	<	newFirst = new HashEntry<K,V>(p.key, p.hash,
2306	<	newFirst, p.value);
2307	<	tab[index] = newFirst;
2308	<	count = c; // write-volatile
2309	<	}
2310	<	}
2311	<	return oldValue;
2312	<	} finally {
2313	<	unlock();
2283	>	@SuppressWarnings("unchecked") final V advanceValue() {
2284	>	outer: for (Node<V> e = next;;) {
2285	>	if (e == null || (e = e.next) == null) {
2286	>	Node<V>[] t; int i, len, n; Object ek;
2287	>	if ((t = tab) == null ||
2288	>	baseSize != (len = t.length) ||
2289	>	len < (n = baseLimit) ||
2290	>	baseIndex != (i = index))
2291	>	break;
2292	>	do {
2293	>	if (i < 0 || i >= n) {
2294	>	index = baseIndex = n;
2295	>	next = null;
2296	>	return nextVal = null;
2297	>	}
2298	>	if ((e = tabAt(t, i)) != null && e.hash < 0) {
2299	>	if ((ek = e.key) instanceof TreeBin)
2300	>	e = ((TreeBin<V>)ek).first;
2301	>	else {
2302	>	index = baseIndex = i;
2303	>	next = null;
2304	>	tab = (Node<V>[])ek;
2305	>	break outer;
2306	>	}
2307	>	}
2308	>	++i;
2309	>	} while (e == null);
2310	>	index = baseIndex = i;
2311	>	}
2312	>	V v;
2313	>	K k = (K)e.key;
2314	>	if ((v = e.val) != null) {
2315	>	nextVal = v;
2316	>	nextKey = k;
2317	>	next = e;
2318	>	return v;
2319	>	}
2320		}
2321	+	return advance();
2322		}
2323
2324	<	void clear() {
2325	<	if (count != 0) {
2326	<	lock();
2327	<	try {
2328	<	HashEntry<K,V>[] tab = table;
2329	<	for (int i = 0; i < tab.length ; i++)
2330	<	tab[i] = null;
2331	<	++modCount;
2332	<	count = 0; // write-volatile
2333	<	} finally {
2334	<	unlock();
2324	>	/**
2325	>	* Common case version for key traversal
2326	>	*/
2327	>	@SuppressWarnings("unchecked") final K advanceKey() {
2328	>	outer: for (Node<V> e = next;;) {
2329	>	if (e == null || (e = e.next) == null) {
2330	>	Node<V>[] t; int i, len, n; Object ek;
2331	>	if ((t = tab) == null ||
2332	>	baseSize != (len = t.length) ||
2333	>	len < (n = baseLimit) ||
2334	>	baseIndex != (i = index))
2335	>	break;
2336	>	do {
2337	>	if (i < 0 || i >= n) {
2338	>	index = baseIndex = n;
2339	>	next = null;
2340	>	nextVal = null;
2341	>	return null;
2342	>	}
2343	>	if ((e = tabAt(t, i)) != null && e.hash < 0) {
2344	>	if ((ek = e.key) instanceof TreeBin)
2345	>	e = ((TreeBin<V>)ek).first;
2346	>	else {
2347	>	index = baseIndex = i;
2348	>	next = null;
2349	>	tab = (Node<V>[])ek;
2350	>	break outer;
2351	>	}
2352	>	}
2353	>	++i;
2354	>	} while (e == null);
2355	>	index = baseIndex = i;
2356	>	}
2357	>	V v;
2358	>	K k = (K)e.key;
2359	>	if ((v = e.val) != null) {
2360	>	nextVal = v;
2361	>	nextKey = k;
2362	>	next = e;
2363	>	return k;
2364		}
2365		}
2366	+	return (advance() == null) ? null : nextKey;
2367	+	}
2368	+
2369	+	@SuppressWarnings("unchecked") final void forEachValue(Consumer<? super V> action) {
2370	+	if (action == null) throw new NullPointerException();
2371	+	Node<V>[] t; int i, len, n;
2372	+	if ((t = tab) != null && baseSize == (len = t.length) &&
2373	+	len >= (n = baseLimit) && baseIndex == (i = index)) {
2374	+	Node<V> e = next;
2375	+	index = baseIndex = n;
2376	+	next = null;
2377	+	nextVal = null;
2378	+	outer: for (;; e = e.next) {
2379	+	V v; Object ek;
2380	+	for (; e == null; ++i) {
2381	+	if (i < 0 || i >= n)
2382	+	return;
2383	+	if ((e = tabAt(t, i)) != null && e.hash < 0) {
2384	+	if ((ek = e.key) instanceof TreeBin)
2385	+	e = ((TreeBin<V>)ek).first;
2386	+	else {
2387	+	index = baseIndex = i;
2388	+	tab = (Node<V>[])ek;
2389	+	break outer;
2390	+	}
2391	+	}
2392	+	}
2393	+	if ((v = e.val) != null)
2394	+	action.accept(v);
2395	+	}
2396	+	}
2397	+	V v;
2398	+	while ((v = advance()) != null)
2399	+	action.accept(v);
2400	+	}
2401	+
2402	+	@SuppressWarnings("unchecked") final void forEachKey(Consumer<? super K> action) {
2403	+	if (action == null) throw new NullPointerException();
2404	+	Node<V>[] t; int i, len, n;
2405	+	if ((t = tab) != null && baseSize == (len = t.length) &&
2406	+	len >= (n = baseLimit) && baseIndex == (i = index)) {
2407	+	Node<V> e = next;
2408	+	index = baseIndex = n;
2409	+	next = null;
2410	+	nextVal = null;
2411	+	outer: for (;; e = e.next) {
2412	+	for (; e == null; ++i) {
2413	+	if (i < 0 || i >= n)
2414	+	return;
2415	+	if ((e = tabAt(t, i)) != null && e.hash < 0) {
2416	+	Object ek;
2417	+	if ((ek = e.key) instanceof TreeBin)
2418	+	e = ((TreeBin<V>)ek).first;
2419	+	else {
2420	+	index = baseIndex = i;
2421	+	tab = (Node<V>[])ek;
2422	+	break outer;
2423	+	}
2424	+	}
2425	+	}
2426	+	Object k = e.key;
2427	+	if (e.val != null)
2428	+	action.accept((K)k);
2429	+	}
2430	+	}
2431	+	while (advance() != null)
2432	+	action.accept(nextKey);
2433	+	}
2434	+
2435	+	public final void remove() {
2436	+	K k = nextKey;
2437	+	if (k == null && (advanceValue() == null || (k = nextKey) == null))
2438	+	throw new IllegalStateException();
2439	+	map.internalReplace(k, null, null);
2440	+	}
2441	+
2442	+	public final boolean hasNext() {
2443	+	return nextVal != null || advanceValue() != null;
2444		}
558	–	}
2445
2446	+	public final boolean hasMoreElements() { return hasNext(); }
2447
2448	+	public void compute() { } // default no-op CountedCompleter body
2449	+
2450	+	public long estimateSize() { return batch; }
2451	+
2452	+	/**
2453	+	* Returns a batch value > 0 if this task should (and must) be
2454	+	* split, if so, adding to pending count, and in any case
2455	+	* updating batch value. The initial batch value is approx
2456	+	* exp2 of the number of times (minus one) to split task by
2457	+	* two before executing leaf action. This value is faster to
2458	+	* compute and more convenient to use as a guide to splitting
2459	+	* than is the depth, since it is used while dividing by two
2460	+	* anyway.
2461	+	*/
2462	+	final int preSplit() {
2463	+	int b;  ForkJoinPool pool;
2464	+	if ((b = batch) < 0) { // force initialization
2465	+	int sp = (((pool = getPool()) == null) ?
2466	+	ForkJoinPool.getCommonPoolParallelism() :
2467	+	pool.getParallelism()) << 3; // slack of 8
2468	+	long n = map.sumCount();
2469	+	b = (n <= 0L) ? 0 : (n < (long)sp) ? (int)n : sp;
2470	+	}
2471	+	b = (b <= 1 || baseIndex >= baseLimit) ? 0 : (b >>> 1);
2472	+	if ((batch = b) > 0)
2473	+	addToPendingCount(1);
2474	+	return b;
2475	+	}
2476	+	}
2477
2478		/* ---------------- Public operations -------------- */
2479
2480		/**
2481	<	* Creates a new, empty map with the specified initial
2482	<	* capacity, load factor and concurrency level.
2481	>	* Creates a new, empty map with the default initial table size (16).
2482	>	*/
2483	>	public ConcurrentHashMap() {
2484	>	}
2485	>
2486	>	/**
2487	>	* Creates a new, empty map with an initial table size
2488	>	* accommodating the specified number of elements without the need
2489	>	* to dynamically resize.
2490		*
2491	<	* @param initialCapacity the initial capacity. The implementation
2492	<	* performs internal sizing to accommodate this many elements.
2493	<	* @param loadFactor  the load factor threshold, used to control resizing.
2494	<	* 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.
2491	>	* @param initialCapacity The implementation performs internal
2492	>	* sizing to accommodate this many elements.
2493	>	* @throws IllegalArgumentException if the initial capacity of
2494	>	* elements is negative
2495		*/
2496	<	public ConcurrentHashMap(int initialCapacity,
2497	<	float loadFactor, int concurrencyLevel) {
582	<	if (!(loadFactor > 0) || initialCapacity < 0 || concurrencyLevel <= 0)
2496	>	public ConcurrentHashMap(int initialCapacity) {
2497	>	if (initialCapacity < 0)
2498		throw new IllegalArgumentException();
2499	+	int cap = ((initialCapacity >= (MAXIMUM_CAPACITY >>> 1)) ?
2500	+	MAXIMUM_CAPACITY :
2501	+	tableSizeFor(initialCapacity + (initialCapacity >>> 1) + 1));
2502	+	this.sizeCtl = cap;
2503	+	}
2504
2505	<	if (concurrencyLevel > MAX_SEGMENTS)
2506	<	concurrencyLevel = MAX_SEGMENTS;
2507	<
2508	<	// Find power-of-two sizes best matching arguments
2509	<	int sshift = 0;
2510	<	int ssize = 1;
2511	<	while (ssize < concurrencyLevel) {
2512	<	++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;
607	<
608	<	for (int i = 0; i < this.segments.length; ++i)
609	<	this.segments[i] = new Segment<K,V>(cap, loadFactor);
2505	>	/**
2506	>	* Creates a new map with the same mappings as the given map.
2507	>	*
2508	>	* @param m the map
2509	>	*/
2510	>	public ConcurrentHashMap(Map<? extends K, ? extends V> m) {
2511	>	this.sizeCtl = DEFAULT_CAPACITY;
2512	>	internalPutAll(m);
2513		}
2514
2515		/**
2516	<	* Creates a new, empty map with the specified initial capacity
2517	<	* and load factor and with the default concurrencyLevel (16).
2516	>	* Creates a new, empty map with an initial table size based on
2517	>	* the given number of elements ({@code initialCapacity}) and
2518	>	* initial table density ({@code loadFactor}).
2519		*
2520	<	* @param initialCapacity The implementation performs internal
2521	<	* sizing to accommodate this many elements.
2522	<	* @param loadFactor  the load factor threshold, used to control resizing.
2523	<	* Resizing may be performed when the average number of elements per
2524	<	* bin exceeds this threshold.
2520	>	* @param initialCapacity the initial capacity. The implementation
2521	>	* performs internal sizing to accommodate this many elements,
2522	>	* given the specified load factor.
2523	>	* @param loadFactor the load factor (table density) for
2524	>	* establishing the initial table size
2525		* @throws IllegalArgumentException if the initial capacity of
2526		* elements is negative or the load factor is nonpositive
2527		*
2528		* @since 1.6
2529		*/
2530		public ConcurrentHashMap(int initialCapacity, float loadFactor) {
2531	<	this(initialCapacity, loadFactor, DEFAULT_CONCURRENCY_LEVEL);
2531	>	this(initialCapacity, loadFactor, 1);
2532		}
2533
2534		/**
2535	<	* Creates a new, empty map with the specified initial capacity,
2536	<	* and with default load factor (0.75) and concurrencyLevel (16).
2535	>	* Creates a new, empty map with an initial table size based on
2536	>	* the given number of elements ({@code initialCapacity}), table
2537	>	* density ({@code loadFactor}), and number of concurrently
2538	>	* updating threads ({@code concurrencyLevel}).
2539		*
2540		* @param initialCapacity the initial capacity. The implementation
2541	<	* performs internal sizing to accommodate this many elements.
2542	<	* @throws IllegalArgumentException if the initial capacity of
2543	<	* elements is negative.
2541	>	* performs internal sizing to accommodate this many elements,
2542	>	* given the specified load factor.
2543	>	* @param loadFactor the load factor (table density) for
2544	>	* establishing the initial table size
2545	>	* @param concurrencyLevel the estimated number of concurrently
2546	>	* updating threads. The implementation may use this value as
2547	>	* a sizing hint.
2548	>	* @throws IllegalArgumentException if the initial capacity is
2549	>	* negative or the load factor or concurrencyLevel are
2550	>	* nonpositive
2551		*/
2552	<	public ConcurrentHashMap(int initialCapacity) {
2553	<	this(initialCapacity, DEFAULT_LOAD_FACTOR, DEFAULT_CONCURRENCY_LEVEL);
2552	>	public ConcurrentHashMap(int initialCapacity,
2553	>	float loadFactor, int concurrencyLevel) {
2554	>	if (!(loadFactor > 0.0f) || initialCapacity < 0 || concurrencyLevel <= 0)
2555	>	throw new IllegalArgumentException();
2556	>	if (initialCapacity < concurrencyLevel)   // Use at least as many bins
2557	>	initialCapacity = concurrencyLevel;   // as estimated threads
2558	>	long size = (long)(1.0 + (long)initialCapacity / loadFactor);
2559	>	int cap = (size >= (long)MAXIMUM_CAPACITY) ?
2560	>	MAXIMUM_CAPACITY : tableSizeFor((int)size);
2561	>	this.sizeCtl = cap;
2562		}
2563
2564		/**
2565	<	* Creates a new, empty map with a default initial capacity (16),
2566	<	* load factor (0.75) and concurrencyLevel (16).
2565	>	* Creates a new {@link Set} backed by a ConcurrentHashMap
2566	>	* from the given type to {@code Boolean.TRUE}.
2567	>	*
2568	>	* @return the new set
2569		*/
2570	<	public ConcurrentHashMap() {
2571	<	this(DEFAULT_INITIAL_CAPACITY, DEFAULT_LOAD_FACTOR, DEFAULT_CONCURRENCY_LEVEL);
2570	>	public static <K> KeySetView<K,Boolean> newKeySet() {
2571	>	return new KeySetView<K,Boolean>
2572	>	(new ConcurrentHashMap<K,Boolean>(), Boolean.TRUE);
2573		}
2574
2575		/**
2576	<	* Creates a new map with the same mappings as the given map.
2577	<	* 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).
2576	>	* Creates a new {@link Set} backed by a ConcurrentHashMap
2577	>	* from the given type to {@code Boolean.TRUE}.
2578		*
2579	<	* @param m the map
2579	>	* @param initialCapacity The implementation performs internal
2580	>	* sizing to accommodate this many elements.
2581	>	* @throws IllegalArgumentException if the initial capacity of
2582	>	* elements is negative
2583	>	* @return the new set
2584		*/
2585	<	public ConcurrentHashMap(Map<? extends K, ? extends V> m) {
2586	<	this(Math.max((int) (m.size() / DEFAULT_LOAD_FACTOR) + 1,
2587	<	DEFAULT_INITIAL_CAPACITY),
662	<	DEFAULT_LOAD_FACTOR, DEFAULT_CONCURRENCY_LEVEL);
663	<	putAll(m);
2585	>	public static <K> KeySetView<K,Boolean> newKeySet(int initialCapacity) {
2586	>	return new KeySetView<K,Boolean>
2587	>	(new ConcurrentHashMap<K,Boolean>(initialCapacity), Boolean.TRUE);
2588		}
2589
2590		/**
2591	<	* Returns <tt>true</tt> if this map contains no key-value mappings.
668	<	*
669	<	* @return <tt>true</tt> if this map contains no key-value mappings
2591	>	* {@inheritDoc}
2592		*/
2593		public boolean isEmpty() {
2594	<	final Segment<K,V>[] segments = this.segments;
673	<	/*
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;
2594	>	return sumCount() <= 0L; // ignore transient negative values
2595		}
2596
2597		/**
2598	<	* Returns the number of key-value mappings in this map.  If the
705	<	* map contains more than <tt>Integer.MAX_VALUE</tt> elements, returns
706	<	* <tt>Integer.MAX_VALUE</tt>.
707	<	*
708	<	* @return the number of key-value mappings in this map
2598	>	* {@inheritDoc}
2599		*/
2600		public int size() {
2601	<	final Segment<K,V>[] segments = this.segments;
2602	<	long sum = 0;
2603	<	long check = 0;
2604	<	int[] mc = new int[segments.length];
2605	<	// Try a few times to get accurate count. On failure due to
2606	<	// continuous async changes in table, resort to locking.
2607	<	for (int k = 0; k < RETRIES_BEFORE_LOCK; ++k) {
2608	<	check = 0;
2609	<	sum = 0;
2610	<	int mcsum = 0;
2611	<	for (int i = 0; i < segments.length; ++i) {
2612	<	sum += segments[i].count;
2613	<	mcsum += mc[i] = segments[i].modCount;
2614	<	}
2615	<	if (mcsum != 0) {
2616	<	for (int i = 0; i < segments.length; ++i) {
2617	<	check += segments[i].count;
2618	<	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;
2601	>	long n = sumCount();
2602	>	return ((n < 0L) ? 0 :
2603	>	(n > (long)Integer.MAX_VALUE) ? Integer.MAX_VALUE :
2604	>	(int)n);
2605	>	}
2606	>
2607	>	/**
2608	>	* Returns the number of mappings. This method should be used
2609	>	* instead of {@link #size} because a ConcurrentHashMap may
2610	>	* contain more mappings than can be represented as an int. The
2611	>	* value returned is an estimate; the actual count may differ if
2612	>	* there are concurrent insertions or removals.
2613	>	*
2614	>	* @return the number of mappings
2615	>	*/
2616	>	public long mappingCount() {
2617	>	long n = sumCount();
2618	>	return (n < 0L) ? 0L : n; // ignore transient negative values
2619		}
2620
2621		/**
2622	<	* Returns the value to which this map maps the specified key, or
2623	<	* <tt>null</tt> if the map contains no mapping for the key.
2622	>	* Returns the value to which the specified key is mapped,
2623	>	* or {@code null} if this map contains no mapping for the key.
2624	>	*
2625	>	* <p>More formally, if this map contains a mapping from a key
2626	>	* {@code k} to a value {@code v} such that {@code key.equals(k)},
2627	>	* then this method returns {@code v}; otherwise it returns
2628	>	* {@code null}.  (There can be at most one such mapping.)
2629		*
756	–	* @param key key whose associated value is to be returned
757	–	* @return the value to which this map maps the specified key, or
758	–	*         <tt>null</tt> if the map contains no mapping for the key
2630		* @throws NullPointerException if the specified key is null
2631		*/
2632		public V get(Object key) {
2633	<	int hash = hash(key); // throws NullPointerException if key null
2634	<	return segmentFor(hash).get(key, hash);
2633	>	return internalGet(key);
2634	>	}
2635	>
2636	>	/**
2637	>	* Returns the value to which the specified key is mapped,
2638	>	* or the given defaultValue if this map contains no mapping for the key.
2639	>	*
2640	>	* @param key the key
2641	>	* @param defaultValue the value to return if this map contains
2642	>	* no mapping for the given key
2643	>	* @return the mapping for the key, if present; else the defaultValue
2644	>	* @throws NullPointerException if the specified key is null
2645	>	*/
2646	>	public V getValueOrDefault(Object key, V defaultValue) {
2647	>	V v;
2648	>	return (v = internalGet(key)) == null ? defaultValue : v;
2649		}
2650
2651		/**
2652		* Tests if the specified object is a key in this table.
2653		*
2654	<	* @param  key   possible key
2655	<	* @return <tt>true</tt> if and only if the specified object
2654	>	* @param  key possible key
2655	>	* @return {@code true} if and only if the specified object
2656		*         is a key in this table, as determined by the
2657	<	*         <tt>equals</tt> method; <tt>false</tt> otherwise.
2657	>	*         {@code equals} method; {@code false} otherwise
2658		* @throws NullPointerException if the specified key is null
2659		*/
2660		public boolean containsKey(Object key) {
2661	<	int hash = hash(key); // throws NullPointerException if key null
777	<	return segmentFor(hash).containsKey(key, hash);
2661	>	return internalGet(key) != null;
2662		}
2663
2664		/**
2665	<	* Returns <tt>true</tt> if this map maps one or more keys to the
2666	<	* specified value. Note: This method requires a full internal
2667	<	* traversal of the hash table, and so is much slower than
784	<	* method <tt>containsKey</tt>.
2665	>	* Returns {@code true} if this map maps one or more keys to the
2666	>	* specified value. Note: This method may require a full traversal
2667	>	* of the map, and is much slower than method {@code containsKey}.
2668		*
2669		* @param value value whose presence in this map is to be tested
2670	<	* @return <tt>true</tt> if this map maps one or more keys to the
2670	>	* @return {@code true} if this map maps one or more keys to the
2671		*         specified value
2672		* @throws NullPointerException if the specified value is null
2673		*/
2674		public boolean containsValue(Object value) {
2675		if (value == null)
2676		throw new NullPointerException();
2677	<
2678	<	// See explanation of modCount use above
2679	<
2680	<	final Segment<K,V>[] segments = this.segments;
2681	<	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();
2677	>	V v;
2678	>	Traverser<K,V,Object> it = new Traverser<K,V,Object>(this);
2679	>	while ((v = it.advanceValue()) != null) {
2680	>	if (v == value || value.equals(v))
2681	>	return true;
2682		}
2683	<	return found;
2683	>	return false;
2684		}
2685
2686		/**
2687		* Legacy method testing if some key maps into the specified value
2688		* in this table.  This method is identical in functionality to
2689	<	* {@link #containsValue}, and exists solely to ensure
2689	>	* {@link #containsValue(Object)}, and exists solely to ensure
2690		* full compatibility with class {@link java.util.Hashtable},
2691		* which supported this method prior to introduction of the
2692		* Java Collections framework.
2693	<
2693	>	*
2694		* @param  value a value to search for
2695	<	* @return <tt>true</tt> if and only if some key maps to the
2696	<	*         <tt>value</tt> argument in this table as
2697	<	*         determined by the <tt>equals</tt> method;
2698	<	*         <tt>false</tt> otherwise
2695	>	* @return {@code true} if and only if some key maps to the
2696	>	*         {@code value} argument in this table as
2697	>	*         determined by the {@code equals} method;
2698	>	*         {@code false} otherwise
2699		* @throws NullPointerException if the specified value is null
2700		*/
2701	<	public boolean contains(Object value) {
2701	>	@Deprecated public boolean contains(Object value) {
2702		return containsValue(value);
2703		}
2704
#	Line 861 | Line 2706 | public class ConcurrentHashMap<K, V> ext
2706		* Maps the specified key to the specified value in this table.
2707		* Neither the key nor the value can be null.
2708		*
2709	<	* <p> The value can be retrieved by calling the <tt>get</tt> method
2709	>	* <p>The value can be retrieved by calling the {@code get} method
2710		* with a key that is equal to the original key.
2711		*
2712		* @param key key with which the specified value is to be associated
2713		* @param value value to be associated with the specified key
2714	<	* @return the previous value associated with <tt>key</tt>, or
2715	<	*         <tt>null</tt> if there was no mapping for <tt>key</tt>
2714	>	* @return the previous value associated with {@code key}, or
2715	>	*         {@code null} if there was no mapping for {@code key}
2716		* @throws NullPointerException if the specified key or value is null
2717		*/
2718		public V put(K key, V value) {
2719	<	if (value == null)
875	<	throw new NullPointerException();
876	<	int hash = hash(key);
877	<	return segmentFor(hash).put(key, hash, value, false);
2719	>	return internalPut(key, value, false);
2720		}
2721
2722		/**
2723		* {@inheritDoc}
2724		*
2725		* @return the previous value associated with the specified key,
2726	<	*         or <tt>null</tt> if there was no mapping for the key
2726	>	*         or {@code null} if there was no mapping for the key
2727		* @throws NullPointerException if the specified key or value is null
2728		*/
2729		public V putIfAbsent(K key, V value) {
2730	<	if (value == null)
889	<	throw new NullPointerException();
890	<	int hash = hash(key);
891	<	return segmentFor(hash).put(key, hash, value, true);
2730	>	return internalPut(key, value, true);
2731		}
2732
2733		/**
#	Line 899 | Line 2738 | public class ConcurrentHashMap<K, V> ext
2738		* @param m mappings to be stored in this map
2739		*/
2740		public void putAll(Map<? extends K, ? extends V> m) {
2741	<	for (Iterator<? extends Map.Entry<? extends K, ? extends V>> it = (Iterator<? extends Map.Entry<? extends K, ? extends V>>) m.entrySet().iterator(); it.hasNext(); ) {
2742	<	Entry<? extends K, ? extends V> e = it.next();
2743	<	put(e.getKey(), e.getValue());
2744	<	}
2741	>	internalPutAll(m);
2742	>	}
2743	>
2744	>	/**
2745	>	* If the specified key is not already associated with a value (or
2746	>	* is mapped to {@code null}), attempts to compute its value using
2747	>	* the given mapping function and enters it into this map unless
2748	>	* {@code null}. The entire method invocation is performed
2749	>	* atomically, so the function is applied at most once per key.
2750	>	* Some attempted update operations on this map by other threads
2751	>	* may be blocked while computation is in progress, so the
2752	>	* computation should be short and simple, and must not attempt to
2753	>	* update any other mappings of this Map.
2754	>	*
2755	>	* @param key key with which the specified value is to be associated
2756	>	* @param mappingFunction the function to compute a value
2757	>	* @return the current (existing or computed) value associated with
2758	>	*         the specified key, or null if the computed value is null
2759	>	* @throws NullPointerException if the specified key or mappingFunction
2760	>	*         is null
2761	>	* @throws IllegalStateException if the computation detectably
2762	>	*         attempts a recursive update to this map that would
2763	>	*         otherwise never complete
2764	>	* @throws RuntimeException or Error if the mappingFunction does so,
2765	>	*         in which case the mapping is left unestablished
2766	>	*/
2767	>	public V computeIfAbsent
2768	>	(K key, Function<? super K, ? extends V> mappingFunction) {
2769	>	return internalComputeIfAbsent(key, mappingFunction);
2770	>	}
2771	>
2772	>	/**
2773	>	* If the value for the specified key is present and non-null,
2774	>	* attempts to compute a new mapping given the key and its current
2775	>	* mapped value.  The entire method invocation is performed
2776	>	* atomically.  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	>	* @param key key with which the specified value is to be associated
2782	>	* @param remappingFunction the function to compute a value
2783	>	* @return the new value associated with the specified key, or null if none
2784	>	* @throws NullPointerException if the specified key or remappingFunction
2785	>	*         is null
2786	>	* @throws IllegalStateException if the computation detectably
2787	>	*         attempts a recursive update to this map that would
2788	>	*         otherwise never complete
2789	>	* @throws RuntimeException or Error if the remappingFunction does so,
2790	>	*         in which case the mapping is unchanged
2791	>	*/
2792	>	public V computeIfPresent
2793	>	(K key, BiFunction<? super K, ? super V, ? extends V> remappingFunction) {
2794	>	return internalCompute(key, true, remappingFunction);
2795	>	}
2796	>
2797	>	/**
2798	>	* Attempts to compute a mapping for the specified key and its
2799	>	* current mapped value (or {@code null} if there is no current
2800	>	* mapping). The entire method invocation is performed atomically.
2801	>	* Some attempted update operations on this map by other threads
2802	>	* may be blocked while computation is in progress, so the
2803	>	* computation should be short and simple, and must not attempt to
2804	>	* update any other mappings of this Map.
2805	>	*
2806	>	* @param key key with which the specified value is to be associated
2807	>	* @param remappingFunction the function to compute a value
2808	>	* @return the new value associated with the specified key, or null if none
2809	>	* @throws NullPointerException if the specified key or remappingFunction
2810	>	*         is null
2811	>	* @throws IllegalStateException if the computation detectably
2812	>	*         attempts a recursive update to this map that would
2813	>	*         otherwise never complete
2814	>	* @throws RuntimeException or Error if the remappingFunction does so,
2815	>	*         in which case the mapping is unchanged
2816	>	*/
2817	>	public V compute
2818	>	(K key, BiFunction<? super K, ? super V, ? extends V> remappingFunction) {
2819	>	return internalCompute(key, false, remappingFunction);
2820	>	}
2821	>
2822	>	/**
2823	>	* If the specified key is not already associated with a
2824	>	* (non-null) value, associates it with the given value.
2825	>	* Otherwise, replaces the value with the results of the given
2826	>	* remapping function, or removes if {@code null}. The entire
2827	>	* method invocation is performed atomically.  Some attempted
2828	>	* update operations on this map by other threads may be blocked
2829	>	* while computation is in progress, so the computation should be
2830	>	* short and simple, and must not attempt to update any other
2831	>	* mappings of this Map.
2832	>	*
2833	>	* @param key key with which the specified value is to be associated
2834	>	* @param value the value to use if absent
2835	>	* @param remappingFunction the function to recompute a value if present
2836	>	* @return the new value associated with the specified key, or null if none
2837	>	* @throws NullPointerException if the specified key or the
2838	>	*         remappingFunction is null
2839	>	* @throws RuntimeException or Error if the remappingFunction does so,
2840	>	*         in which case the mapping is unchanged
2841	>	*/
2842	>	public V merge
2843	>	(K key, V value,
2844	>	BiFunction<? super V, ? super V, ? extends V> remappingFunction) {
2845	>	return internalMerge(key, value, remappingFunction);
2846		}
2847
2848		/**
#	Line 910 | Line 2850 | public class ConcurrentHashMap<K, V> ext
2850		* This method does nothing if the key is not in the map.
2851		*
2852		* @param  key the key that needs to be removed
2853	<	* @return the previous value associated with <tt>key</tt>, or
2854	<	*         <tt>null</tt> if there was no mapping for <tt>key</tt>.
2853	>	* @return the previous value associated with {@code key}, or
2854	>	*         {@code null} if there was no mapping for {@code key}
2855		* @throws NullPointerException if the specified key is null
2856		*/
2857		public V remove(Object key) {
2858	<	int hash = hash(key);
919	<	return segmentFor(hash).remove(key, hash, null);
2858	>	return internalReplace(key, null, null);
2859		}
2860
2861		/**
#	Line 925 | Line 2864 | public class ConcurrentHashMap<K, V> ext
2864		* @throws NullPointerException if the specified key is null
2865		*/
2866		public boolean remove(Object key, Object value) {
2867	<	if (value == null)
2868	<	return false;
2869	<	int hash = hash(key);
931	<	return segmentFor(hash).remove(key, hash, value) != null;
2867	>	if (key == null)
2868	>	throw new NullPointerException();
2869	>	return value != null && internalReplace(key, null, value) != null;
2870		}
2871
2872		/**
#	Line 937 | Line 2875 | public class ConcurrentHashMap<K, V> ext
2875		* @throws NullPointerException if any of the arguments are null
2876		*/
2877		public boolean replace(K key, V oldValue, V newValue) {
2878	<	if (oldValue == null || newValue == null)
2878	>	if (key == null || oldValue == null || newValue == null)
2879		throw new NullPointerException();
2880	<	int hash = hash(key);
943	<	return segmentFor(hash).replace(key, hash, oldValue, newValue);
2880	>	return internalReplace(key, newValue, oldValue) != null;
2881		}
2882
2883		/**
2884		* {@inheritDoc}
2885		*
2886		* @return the previous value associated with the specified key,
2887	<	*         or <tt>null</tt> if there was no mapping for the key
2887	>	*         or {@code null} if there was no mapping for the key
2888		* @throws NullPointerException if the specified key or value is null
2889		*/
2890		public V replace(K key, V value) {
2891	<	if (value == null)
2891	>	if (key == null || value == null)
2892		throw new NullPointerException();
2893	<	int hash = hash(key);
957	<	return segmentFor(hash).replace(key, hash, value);
2893	>	return internalReplace(key, value, null);
2894		}
2895
2896		/**
2897		* Removes all of the mappings from this map.
2898		*/
2899		public void clear() {
2900	<	for (int i = 0; i < segments.length; ++i)
965	<	segments[i].clear();
2900	>	internalClear();
2901		}
2902
2903		/**
2904		* Returns a {@link Set} view of the keys contained in this map.
2905		* The set is backed by the map, so changes to the map are
2906	<	* reflected in the set, and vice-versa.  The set supports element
972	<	* removal, which removes the corresponding mapping from this map,
973	<	* via the <tt>Iterator.remove</tt>, <tt>Set.remove</tt>,
974	<	* <tt>removeAll</tt>, <tt>retainAll</tt>, and <tt>clear</tt>
975	<	* operations.  It does not support the <tt>add</tt> or
976	<	* <tt>addAll</tt> operations.
2906	>	* reflected in the set, and vice-versa.
2907		*
2908	<	* <p>The view's <tt>iterator</tt> is a "weakly consistent" iterator
2909	<	* that will never throw {@link ConcurrentModificationException},
2910	<	* and guarantees to traverse elements as they existed upon
2911	<	* construction of the iterator, and may (but is not guaranteed to)
2912	<	* reflect any modifications subsequent to construction.
2908	>	* @return the set view
2909	>	*/
2910	>	public KeySetView<K,V> keySet() {
2911	>	KeySetView<K,V> ks = keySet;
2912	>	return (ks != null) ? ks : (keySet = new KeySetView<K,V>(this, null));
2913	>	}
2914	>
2915	>	/**
2916	>	* Returns a {@link Set} view of the keys in this map, using the
2917	>	* given common mapped value for any additions (i.e., {@link
2918	>	* Collection#add} and {@link Collection#addAll(Collection)}).
2919	>	* This is of course only appropriate if it is acceptable to use
2920	>	* the same value for all additions from this view.
2921	>	*
2922	>	* @param mappedValue the mapped value to use for any additions
2923	>	* @return the set view
2924	>	* @throws NullPointerException if the mappedValue is null
2925		*/
2926	<	public Set<K> keySet() {
2927	<	Set<K> ks = keySet;
2928	<	return (ks != null) ? ks : (keySet = new KeySet());
2926	>	public KeySetView<K,V> keySet(V mappedValue) {
2927	>	if (mappedValue == null)
2928	>	throw new NullPointerException();
2929	>	return new KeySetView<K,V>(this, mappedValue);
2930		}
2931
2932		/**
2933		* Returns a {@link Collection} view of the values contained in this map.
2934		* The collection is backed by the map, so changes to the map are
2935	<	* reflected in the collection, and vice-versa.  The collection
993	<	* supports element removal, which removes the corresponding
994	<	* mapping from this map, via the <tt>Iterator.remove</tt>,
995	<	* <tt>Collection.remove</tt>, <tt>removeAll</tt>,
996	<	* <tt>retainAll</tt>, and <tt>clear</tt> operations.  It does not
997	<	* support the <tt>add</tt> or <tt>addAll</tt> operations.
2935	>	* reflected in the collection, and vice-versa.
2936		*
2937	<	* <p>The view's <tt>iterator</tt> is a "weakly consistent" iterator
1000	<	* that will never throw {@link ConcurrentModificationException},
1001	<	* and guarantees to traverse elements as they existed upon
1002	<	* construction of the iterator, and may (but is not guaranteed to)
1003	<	* reflect any modifications subsequent to construction.
2937	>	* @return the collection view
2938		*/
2939	<	public Collection<V> values() {
2940	<	Collection<V> vs = values;
2941	<	return (vs != null) ? vs : (values = new Values());
2939	>	public ValuesView<K,V> values() {
2940	>	ValuesView<K,V> vs = values;
2941	>	return (vs != null) ? vs : (values = new ValuesView<K,V>(this));
2942		}
2943
2944		/**
#	Line 1012 | Line 2946 | public class ConcurrentHashMap<K, V> ext
2946		* The set is backed by the map, so changes to the map are
2947		* reflected in the set, and vice-versa.  The set supports element
2948		* removal, which removes the corresponding mapping from the map,
2949	<	* via the <tt>Iterator.remove</tt>, <tt>Set.remove</tt>,
2950	<	* <tt>removeAll</tt>, <tt>retainAll</tt>, and <tt>clear</tt>
2951	<	* operations.  It does not support the <tt>add</tt> or
2952	<	* <tt>addAll</tt> operations.
2949	>	* via the {@code Iterator.remove}, {@code Set.remove},
2950	>	* {@code removeAll}, {@code retainAll}, and {@code clear}
2951	>	* operations.  It does not support the {@code add} or
2952	>	* {@code addAll} operations.
2953		*
2954	<	* <p>The view's <tt>iterator</tt> is a "weakly consistent" iterator
2954	>	* <p>The view's {@code iterator} is a "weakly consistent" iterator
2955		* that will never throw {@link ConcurrentModificationException},
2956		* and guarantees to traverse elements as they existed upon
2957		* construction of the iterator, and may (but is not guaranteed to)
2958		* reflect any modifications subsequent to construction.
2959	+	*
2960	+	* @return the set view
2961		*/
2962		public Set<Map.Entry<K,V>> entrySet() {
2963	<	Set<Map.Entry<K,V>> es = entrySet;
2964	<	return (es != null) ? es : (entrySet = new EntrySet());
2963	>	EntrySetView<K,V> es = entrySet;
2964	>	return (es != null) ? es : (entrySet = new EntrySetView<K,V>(this));
2965		}
2966
2967		/**
2968		* Returns an enumeration of the keys in this table.
2969		*
2970		* @return an enumeration of the keys in this table
2971	<	* @see #keySet
2971	>	* @see #keySet()
2972		*/
2973		public Enumeration<K> keys() {
2974	<	return new KeyIterator();
2974	>	return new KeyIterator<K,V>(this);
2975		}
2976
2977		/**
2978		* Returns an enumeration of the values in this table.
2979		*
2980		* @return an enumeration of the values in this table
2981	<	* @see #values
2981	>	* @see #values()
2982		*/
2983		public Enumeration<V> elements() {
2984	<	return new ValueIterator();
2984	>	return new ValueIterator<K,V>(this);
2985	>	}
2986	>
2987	>	/**
2988	>	* Returns the hash code value for this {@link Map}, i.e.,
2989	>	* the sum of, for each key-value pair in the map,
2990	>	* {@code key.hashCode() ^ value.hashCode()}.
2991	>	*
2992	>	* @return the hash code value for this map
2993	>	*/
2994	>	public int hashCode() {
2995	>	int h = 0;
2996	>	Traverser<K,V,Object> it = new Traverser<K,V,Object>(this);
2997	>	V v;
2998	>	while ((v = it.advanceValue()) != null) {
2999	>	h += it.nextKey.hashCode() ^ v.hashCode();
3000	>	}
3001	>	return h;
3002	>	}
3003	>
3004	>	/**
3005	>	* Returns a string representation of this map.  The string
3006	>	* representation consists of a list of key-value mappings (in no
3007	>	* particular order) enclosed in braces ("{@code {}}").  Adjacent
3008	>	* mappings are separated by the characters {@code ", "} (comma
3009	>	* and space).  Each key-value mapping is rendered as the key
3010	>	* followed by an equals sign ("{@code =}") followed by the
3011	>	* associated value.
3012	>	*
3013	>	* @return a string representation of this map
3014	>	*/
3015	>	public String toString() {
3016	>	Traverser<K,V,Object> it = new Traverser<K,V,Object>(this);
3017	>	StringBuilder sb = new StringBuilder();
3018	>	sb.append('{');
3019	>	V v;
3020	>	if ((v = it.advanceValue()) != null) {
3021	>	for (;;) {
3022	>	K k = it.nextKey;
3023	>	sb.append(k == this ? "(this Map)" : k);
3024	>	sb.append('=');
3025	>	sb.append(v == this ? "(this Map)" : v);
3026	>	if ((v = it.advanceValue()) == null)
3027	>	break;
3028	>	sb.append(',').append(' ');
3029	>	}
3030	>	}
3031	>	return sb.append('}').toString();
3032		}
3033
3034	<	/* ---------------- Iterator Support -------------- */
3034	>	/**
3035	>	* Compares the specified object with this map for equality.
3036	>	* Returns {@code true} if the given object is a map with the same
3037	>	* mappings as this map.  This operation may return misleading
3038	>	* results if either map is concurrently modified during execution
3039	>	* of this method.
3040	>	*
3041	>	* @param o object to be compared for equality with this map
3042	>	* @return {@code true} if the specified object is equal to this map
3043	>	*/
3044	>	public boolean equals(Object o) {
3045	>	if (o != this) {
3046	>	if (!(o instanceof Map))
3047	>	return false;
3048	>	Map<?,?> m = (Map<?,?>) o;
3049	>	Traverser<K,V,Object> it = new Traverser<K,V,Object>(this);
3050	>	V val;
3051	>	while ((val = it.advanceValue()) != null) {
3052	>	Object v = m.get(it.nextKey);
3053	>	if (v == null || (v != val && !v.equals(val)))
3054	>	return false;
3055	>	}
3056	>	for (Map.Entry<?,?> e : m.entrySet()) {
3057	>	Object mk, mv, v;
3058	>	if ((mk = e.getKey()) == null ||
3059	>	(mv = e.getValue()) == null ||
3060	>	(v = internalGet(mk)) == null ||
3061	>	(mv != v && !mv.equals(v)))
3062	>	return false;
3063	>	}
3064	>	}
3065	>	return true;
3066	>	}
3067
3068	<	abstract class HashIterator {
1054	<	int nextSegmentIndex;
1055	<	int nextTableIndex;
1056	<	HashEntry<K,V>[] currentTable;
1057	<	HashEntry<K, V> nextEntry;
1058	<	HashEntry<K, V> lastReturned;
3068	>	/* ----------------Iterators -------------- */
3069
3070	<	HashIterator() {
3071	<	nextSegmentIndex = segments.length - 1;
3072	<	nextTableIndex = -1;
3073	<	advance();
3070	>	@SuppressWarnings("serial") static final class KeyIterator<K,V>
3071	>	extends Traverser<K,V,Object>
3072	>	implements Spliterator<K>, Iterator<K>, Enumeration<K> {
3073	>	KeyIterator(ConcurrentHashMap<K,V> map) { super(map); }
3074	>	KeyIterator(ConcurrentHashMap<K,V> map, Traverser<K,V,Object> it) {
3075	>	super(map, it);
3076	>	}
3077	>	public Spliterator<K> trySplit() {
3078	>	return (baseIndex >= baseLimit) ? null :
3079	>	new KeyIterator<K,V>(map, this);
3080	>	}
3081	>	public final K next() {
3082	>	K k;
3083	>	if ((k = (nextVal == null) ? advanceKey() : nextKey) == null)
3084	>	throw new NoSuchElementException();
3085	>	nextVal = null;
3086	>	return k;
3087		}
3088
3089	<	public boolean hasMoreElements() { return hasNext(); }
3089	>	public final K nextElement() { return next(); }
3090
3091	<	final void advance() {
1069	<	if (nextEntry != null && (nextEntry = nextEntry.next) != null)
1070	<	return;
3091	>	public Iterator<K> iterator() { return this; }
3092
3093	<	while (nextTableIndex >= 0) {
3094	<	if ( (nextEntry = currentTable[nextTableIndex--]) != null)
3095	<	return;
1075	<	}
3093	>	public void forEach(Consumer<? super K> action) {
3094	>	forEachKey(action);
3095	>	}
3096
3097	<	while (nextSegmentIndex >= 0) {
3098	<	Segment<K,V> seg = segments[nextSegmentIndex--];
3099	<	if (seg.count != 0) {
3100	<	currentTable = seg.table;
3101	<	for (int j = currentTable.length - 1; j >= 0; --j) {
3102	<	if ( (nextEntry = currentTable[j]) != null) {
3103	<	nextTableIndex = j - 1;
1084	<	return;
1085	<	}
1086	<	}
1087	<	}
1088	<	}
3097	>	public boolean tryAdvance(Consumer<? super K> block) {
3098	>	if (block == null) throw new NullPointerException();
3099	>	K k;
3100	>	if ((k = advanceKey()) == null)
3101	>	return false;
3102	>	block.accept(k);
3103	>	return true;
3104		}
3105
3106	<	public boolean hasNext() { return nextEntry != null; }
3106	>	public int characteristics() {
3107	>	return Spliterator.DISTINCT | Spliterator.CONCURRENT |
3108	>	Spliterator.NONNULL;
3109	>	}
3110	>
3111	>	}
3112
3113	<	HashEntry<K,V> nextEntry() {
3114	<	if (nextEntry == null)
3113	>	@SuppressWarnings("serial") static final class ValueIterator<K,V>
3114	>	extends Traverser<K,V,Object>
3115	>	implements Spliterator<V>, Iterator<V>, Enumeration<V> {
3116	>	ValueIterator(ConcurrentHashMap<K,V> map) { super(map); }
3117	>	ValueIterator(ConcurrentHashMap<K,V> map, Traverser<K,V,Object> it) {
3118	>	super(map, it);
3119	>	}
3120	>	public Spliterator<V> trySplit() {
3121	>	return (baseIndex >= baseLimit) ? null :
3122	>	new ValueIterator<K,V>(map, this);
3123	>	}
3124	>
3125	>	public final V next() {
3126	>	V v;
3127	>	if ((v = nextVal) == null && (v = advanceValue()) == null)
3128		throw new NoSuchElementException();
3129	<	lastReturned = nextEntry;
3130	<	advance();
1098	<	return lastReturned;
3129	>	nextVal = null;
3130	>	return v;
3131		}
3132
3133	<	public void remove() {
3134	<	if (lastReturned == null)
3135	<	throw new IllegalStateException();
3136	<	ConcurrentHashMap.this.remove(lastReturned.key);
3137	<	lastReturned = null;
3133	>	public final V nextElement() { return next(); }
3134	>
3135	>	public Iterator<V> iterator() { return this; }
3136	>
3137	>	public void forEach(Consumer<? super V> action) {
3138	>	forEachValue(action);
3139		}
1107	–	}
3140
3141	<	final class KeyIterator
3142	<	extends HashIterator
3143	<	implements Iterator<K>, Enumeration<K>
3144	<	{
3145	<	public K next()        { return super.nextEntry().key; }
3146	<	public K nextElement() { return super.nextEntry().key; }
3141	>	public boolean tryAdvance(Consumer<? super V> block) {
3142	>	V v;
3143	>	if (block == null) throw new NullPointerException();
3144	>	if ((v = advanceValue()) == null)
3145	>	return false;
3146	>	block.accept(v);
3147	>	return true;
3148	>	}
3149	>
3150	>	public int characteristics() {
3151	>	return Spliterator.CONCURRENT | Spliterator.NONNULL;
3152	>	}
3153		}
3154
3155	<	final class ValueIterator
3156	<	extends HashIterator
3157	<	implements Iterator<V>, Enumeration<V>
3158	<	{
3159	<	public V next()        { return super.nextEntry().value; }
3160	<	public V nextElement() { return super.nextEntry().value; }
3155	>	@SuppressWarnings("serial") static final class EntryIterator<K,V>
3156	>	extends Traverser<K,V,Object>
3157	>	implements Spliterator<Map.Entry<K,V>>, Iterator<Map.Entry<K,V>> {
3158	>	EntryIterator(ConcurrentHashMap<K,V> map) { super(map); }
3159	>	EntryIterator(ConcurrentHashMap<K,V> map, Traverser<K,V,Object> it) {
3160	>	super(map, it);
3161	>	}
3162	>	public Spliterator<Map.Entry<K,V>> trySplit() {
3163	>	return (baseIndex >= baseLimit) ? null :
3164	>	new EntryIterator<K,V>(map, this);
3165	>	}
3166	>
3167	>	public final Map.Entry<K,V> next() {
3168	>	V v;
3169	>	if ((v = nextVal) == null && (v = advanceValue()) == null)
3170	>	throw new NoSuchElementException();
3171	>	K k = nextKey;
3172	>	nextVal = null;
3173	>	return new MapEntry<K,V>(k, v, map);
3174	>	}
3175	>
3176	>	public Iterator<Map.Entry<K,V>> iterator() { return this; }
3177	>
3178	>	public void forEach(Consumer<? super Map.Entry<K,V>> action) {
3179	>	if (action == null) throw new NullPointerException();
3180	>	V v;
3181	>	while ((v = advanceValue()) != null)
3182	>	action.accept(entryFor(nextKey, v));
3183	>	}
3184	>
3185	>	public boolean tryAdvance(Consumer<? super Map.Entry<K,V>> block) {
3186	>	V v;
3187	>	if (block == null) throw new NullPointerException();
3188	>	if ((v = advanceValue()) == null)
3189	>	return false;
3190	>	block.accept(entryFor(nextKey, v));
3191	>	return true;
3192	>	}
3193	>
3194	>	public int characteristics() {
3195	>	return Spliterator.DISTINCT | Spliterator.CONCURRENT |
3196	>	Spliterator.NONNULL;
3197	>	}
3198		}
3199
3200		/**
3201	<	* Custom Entry class used by EntryIterator.next(), that relays
1127	<	* setValue changes to the underlying map.
3201	>	* Exported Entry for iterators
3202		*/
3203	<	final class WriteThroughEntry
3204	<	extends AbstractMap.SimpleEntry<K,V>
3205	<	{
3206	<	WriteThroughEntry(K k, V v) {
3207	<	super(k,v);
3203	>	static final class MapEntry<K,V> implements Map.Entry<K,V> {
3204	>	final K key; // non-null
3205	>	V val;       // non-null
3206	>	final ConcurrentHashMap<K,V> map;
3207	>	MapEntry(K key, V val, ConcurrentHashMap<K,V> map) {
3208	>	this.key = key;
3209	>	this.val = val;
3210	>	this.map = map;
3211	>	}
3212	>	public final K getKey()       { return key; }
3213	>	public final V getValue()     { return val; }
3214	>	public final int hashCode()   { return key.hashCode() ^ val.hashCode(); }
3215	>	public final String toString(){ return key + "=" + val; }
3216	>
3217	>	public final boolean equals(Object o) {
3218	>	Object k, v; Map.Entry<?,?> e;
3219	>	return ((o instanceof Map.Entry) &&
3220	>	(k = (e = (Map.Entry<?,?>)o).getKey()) != null &&
3221	>	(v = e.getValue()) != null &&
3222	>	(k == key || k.equals(key)) &&
3223	>	(v == val || v.equals(val)));
3224		}
3225
3226		/**
3227	<	* Set our entry's value and write through to the map. The
3228	<	* value to return is somewhat arbitrary here. Since a
3229	<	* WriteThroughEntry does not necessarily track asynchronous
3230	<	* changes, the most recent "previous" value could be
3231	<	* different from what we return (or could even have been
3232	<	* removed in which case the put will re-establish). We do not
1143	<	* and cannot guarantee more.
3227	>	* Sets our entry's value and writes through to the map. The
3228	>	* value to return is somewhat arbitrary here. Since we do not
3229	>	* necessarily track asynchronous changes, the most recent
3230	>	* "previous" value could be different from what we return (or
3231	>	* could even have been removed in which case the put will
3232	>	* re-establish). We do not and cannot guarantee more.
3233		*/
3234	<	public V setValue(V value) {
3234	>	public final V setValue(V value) {
3235		if (value == null) throw new NullPointerException();
3236	<	V v = super.setValue(value);
3237	<	ConcurrentHashMap.this.put(getKey(), value);
3236	>	V v = val;
3237	>	val = value;
3238	>	map.put(key, value);
3239		return v;
3240		}
3241		}
3242
3243	<	final class EntryIterator
3244	<	extends HashIterator
3245	<	implements Iterator<Entry<K,V>>
3246	<	{
3247	<	public Map.Entry<K,V> next() {
3248	<	HashEntry<K,V> e = super.nextEntry();
3249	<	return new WriteThroughEntry(e.key, e.value);
3243	>	/**
3244	>	* Returns exportable snapshot entry for the given key and value
3245	>	* when write-through can't or shouldn't be used.
3246	>	*/
3247	>	static <K,V> AbstractMap.SimpleEntry<K,V> entryFor(K k, V v) {
3248	>	return new AbstractMap.SimpleEntry<K,V>(k, v);
3249	>	}
3250	>
3251	>	/* ---------------- Serialization Support -------------- */
3252	>
3253	>	/**
3254	>	* Stripped-down version of helper class used in previous version,
3255	>	* declared for the sake of serialization compatibility
3256	>	*/
3257	>	static class Segment<K,V> implements Serializable {
3258	>	private static final long serialVersionUID = 2249069246763182397L;
3259	>	final float loadFactor;
3260	>	Segment(float lf) { this.loadFactor = lf; }
3261	>	}
3262	>
3263	>	/**
3264	>	* Saves the state of the {@code ConcurrentHashMap} instance to a
3265	>	* stream (i.e., serializes it).
3266	>	* @param s the stream
3267	>	* @serialData
3268	>	* the key (Object) and value (Object)
3269	>	* for each key-value mapping, followed by a null pair.
3270	>	* The key-value mappings are emitted in no particular order.
3271	>	*/
3272	>	@SuppressWarnings("unchecked") private void writeObject
3273	>	(java.io.ObjectOutputStream s)
3274	>	throws java.io.IOException {
3275	>	if (segments == null) { // for serialization compatibility
3276	>	segments = (Segment<K,V>[])
3277	>	new Segment<?,?>[DEFAULT_CONCURRENCY_LEVEL];
3278	>	for (int i = 0; i < segments.length; ++i)
3279	>	segments[i] = new Segment<K,V>(LOAD_FACTOR);
3280	>	}
3281	>	s.defaultWriteObject();
3282	>	Traverser<K,V,Object> it = new Traverser<K,V,Object>(this);
3283	>	V v;
3284	>	while ((v = it.advanceValue()) != null) {
3285	>	s.writeObject(it.nextKey);
3286	>	s.writeObject(v);
3287		}
3288	+	s.writeObject(null);
3289	+	s.writeObject(null);
3290	+	segments = null; // throw away
3291		}
3292
3293	<	final class KeySet extends AbstractSet<K> {
3294	<	public Iterator<K> iterator() {
3295	<	return new KeyIterator();
3293	>	/**
3294	>	* Reconstitutes the instance from a stream (that is, deserializes it).
3295	>	* @param s the stream
3296	>	*/
3297	>	@SuppressWarnings("unchecked") private void readObject
3298	>	(java.io.ObjectInputStream s)
3299	>	throws java.io.IOException, ClassNotFoundException {
3300	>	s.defaultReadObject();
3301	>	this.segments = null; // unneeded
3302	>
3303	>	// Create all nodes, then place in table once size is known
3304	>	long size = 0L;
3305	>	Node<V> p = null;
3306	>	for (;;) {
3307	>	K k = (K) s.readObject();
3308	>	V v = (V) s.readObject();
3309	>	if (k != null && v != null) {
3310	>	int h = spread(k.hashCode());
3311	>	p = new Node<V>(h, k, v, p);
3312	>	++size;
3313	>	}
3314	>	else
3315	>	break;
3316		}
3317	<	public int size() {
3318	<	return ConcurrentHashMap.this.size();
3317	>	if (p != null) {
3318	>	boolean init = false;
3319	>	int n;
3320	>	if (size >= (long)(MAXIMUM_CAPACITY >>> 1))
3321	>	n = MAXIMUM_CAPACITY;
3322	>	else {
3323	>	int sz = (int)size;
3324	>	n = tableSizeFor(sz + (sz >>> 1) + 1);
3325	>	}
3326	>	int sc = sizeCtl;
3327	>	boolean collide = false;
3328	>	if (n > sc &&
3329	>	U.compareAndSwapInt(this, SIZECTL, sc, -1)) {
3330	>	try {
3331	>	if (table == null) {
3332	>	init = true;
3333	>	@SuppressWarnings("rawtypes") Node[] rt = new Node[n];
3334	>	Node<V>[] tab = (Node<V>[])rt;
3335	>	int mask = n - 1;
3336	>	while (p != null) {
3337	>	int j = p.hash & mask;
3338	>	Node<V> next = p.next;
3339	>	Node<V> q = p.next = tabAt(tab, j);
3340	>	setTabAt(tab, j, p);
3341	>	if (!collide && q != null && q.hash == p.hash)
3342	>	collide = true;
3343	>	p = next;
3344	>	}
3345	>	table = tab;
3346	>	addCount(size, -1);
3347	>	sc = n - (n >>> 2);
3348	>	}
3349	>	} finally {
3350	>	sizeCtl = sc;
3351	>	}
3352	>	if (collide) { // rescan and convert to TreeBins
3353	>	Node<V>[] tab = table;
3354	>	for (int i = 0; i < tab.length; ++i) {
3355	>	int c = 0;
3356	>	for (Node<V> e = tabAt(tab, i); e != null; e = e.next) {
3357	>	if (++c > TREE_THRESHOLD &&
3358	>	(e.key instanceof Comparable)) {
3359	>	replaceWithTreeBin(tab, i, e.key);
3360	>	break;
3361	>	}
3362	>	}
3363	>	}
3364	>	}
3365	>	}
3366	>	if (!init) { // Can only happen if unsafely published.
3367	>	while (p != null) {
3368	>	internalPut((K)p.key, p.val, false);
3369	>	p = p.next;
3370	>	}
3371	>	}
3372		}
3373	<	public boolean contains(Object o) {
3374	<	return ConcurrentHashMap.this.containsKey(o);
3373	>	}
3374	>
3375	>	// -------------------------------------------------------
3376	>
3377	>	// Sequential bulk operations
3378	>
3379	>	/**
3380	>	* Performs the given action for each (key, value).
3381	>	*
3382	>	* @param action the action
3383	>	*/
3384	>	public void forEachSequentially
3385	>	(BiConsumer<? super K, ? super V> action) {
3386	>	if (action == null) throw new NullPointerException();
3387	>	Traverser<K,V,Object> it = new Traverser<K,V,Object>(this);
3388	>	V v;
3389	>	while ((v = it.advanceValue()) != null)
3390	>	action.accept(it.nextKey, v);
3391	>	}
3392	>
3393	>	/**
3394	>	* Performs the given action for each non-null transformation
3395	>	* of each (key, value).
3396	>	*
3397	>	* @param transformer a function returning the transformation
3398	>	* for an element, or null if there is no transformation (in
3399	>	* which case the action is not applied)
3400	>	* @param action the action
3401	>	*/
3402	>	public <U> void forEachSequentially
3403	>	(BiFunction<? super K, ? super V, ? extends U> transformer,
3404	>	Consumer<? super U> action) {
3405	>	if (transformer == null || action == null)
3406	>	throw new NullPointerException();
3407	>	Traverser<K,V,Object> it = new Traverser<K,V,Object>(this);
3408	>	V v; U u;
3409	>	while ((v = it.advanceValue()) != null) {
3410	>	if ((u = transformer.apply(it.nextKey, v)) != null)
3411	>	action.accept(u);
3412		}
3413	<	public boolean remove(Object o) {
3414	<	return ConcurrentHashMap.this.remove(o) != null;
3413	>	}
3414	>
3415	>	/**
3416	>	* Returns a non-null result from applying the given search
3417	>	* function on each (key, value), or null if none.
3418	>	*
3419	>	* @param searchFunction a function returning a non-null
3420	>	* result on success, else null
3421	>	* @return a non-null result from applying the given search
3422	>	* function on each (key, value), or null if none
3423	>	*/
3424	>	public <U> U searchSequentially
3425	>	(BiFunction<? super K, ? super V, ? extends U> searchFunction) {
3426	>	if (searchFunction == null) throw new NullPointerException();
3427	>	Traverser<K,V,Object> it = new Traverser<K,V,Object>(this);
3428	>	V v; U u;
3429	>	while ((v = it.advanceValue()) != null) {
3430	>	if ((u = searchFunction.apply(it.nextKey, v)) != null)
3431	>	return u;
3432		}
3433	<	public void clear() {
3434	<	ConcurrentHashMap.this.clear();
3433	>	return null;
3434	>	}
3435	>
3436	>	/**
3437	>	* Returns the result of accumulating the given transformation
3438	>	* of all (key, value) pairs using the given reducer to
3439	>	* combine values, or null if none.
3440	>	*
3441	>	* @param transformer a function returning the transformation
3442	>	* for an element, or null if there is no transformation (in
3443	>	* which case it is not combined)
3444	>	* @param reducer a commutative associative combining function
3445	>	* @return the result of accumulating the given transformation
3446	>	* of all (key, value) pairs
3447	>	*/
3448	>	public <U> U reduceSequentially
3449	>	(BiFunction<? super K, ? super V, ? extends U> transformer,
3450	>	BiFunction<? super U, ? super U, ? extends U> reducer) {
3451	>	if (transformer == null || reducer == null)
3452	>	throw new NullPointerException();
3453	>	Traverser<K,V,Object> it = new Traverser<K,V,Object>(this);
3454	>	U r = null, u; V v;
3455	>	while ((v = it.advanceValue()) != null) {
3456	>	if ((u = transformer.apply(it.nextKey, v)) != null)
3457	>	r = (r == null) ? u : reducer.apply(r, u);
3458		}
3459	<	public Object[] toArray() {
3460	<	Collection<K> c = new ArrayList<K>(size());
3461	<	for (K k : this)
3462	<	c.add(k);
3463	<	return c.toArray();
3459	>	return r;
3460	>	}
3461	>
3462	>	/**
3463	>	* Returns the result of accumulating the given transformation
3464	>	* of all (key, value) pairs using the given reducer to
3465	>	* combine values, and the given basis as an identity value.
3466	>	*
3467	>	* @param transformer a function returning the transformation
3468	>	* for an element
3469	>	* @param basis the identity (initial default value) for the reduction
3470	>	* @param reducer a commutative associative combining function
3471	>	* @return the result of accumulating the given transformation
3472	>	* of all (key, value) pairs
3473	>	*/
3474	>	public double reduceToDoubleSequentially
3475	>	(ToDoubleBiFunction<? super K, ? super V> transformer,
3476	>	double basis,
3477	>	DoubleBinaryOperator reducer) {
3478	>	if (transformer == null || reducer == null)
3479	>	throw new NullPointerException();
3480	>	Traverser<K,V,Object> it = new Traverser<K,V,Object>(this);
3481	>	double r = basis; V v;
3482	>	while ((v = it.advanceValue()) != null)
3483	>	r = reducer.applyAsDouble(r, transformer.applyAsDouble(it.nextKey, v));
3484	>	return r;
3485	>	}
3486	>
3487	>	/**
3488	>	* Returns the result of accumulating the given transformation
3489	>	* of all (key, value) pairs using the given reducer to
3490	>	* combine values, and the given basis as an identity value.
3491	>	*
3492	>	* @param transformer a function returning the transformation
3493	>	* for an element
3494	>	* @param basis the identity (initial default value) for the reduction
3495	>	* @param reducer a commutative associative combining function
3496	>	* @return the result of accumulating the given transformation
3497	>	* of all (key, value) pairs
3498	>	*/
3499	>	public long reduceToLongSequentially
3500	>	(ToLongBiFunction<? super K, ? super V> transformer,
3501	>	long basis,
3502	>	LongBinaryOperator reducer) {
3503	>	if (transformer == null || reducer == null)
3504	>	throw new NullPointerException();
3505	>	Traverser<K,V,Object> it = new Traverser<K,V,Object>(this);
3506	>	long r = basis; V v;
3507	>	while ((v = it.advanceValue()) != null)
3508	>	r = reducer.applyAsLong(r, transformer.applyAsLong(it.nextKey, v));
3509	>	return r;
3510	>	}
3511	>
3512	>	/**
3513	>	* Returns the result of accumulating the given transformation
3514	>	* of all (key, value) pairs using the given reducer to
3515	>	* combine values, and the given basis as an identity value.
3516	>	*
3517	>	* @param transformer a function returning the transformation
3518	>	* for an element
3519	>	* @param basis the identity (initial default value) for the reduction
3520	>	* @param reducer a commutative associative combining function
3521	>	* @return the result of accumulating the given transformation
3522	>	* of all (key, value) pairs
3523	>	*/
3524	>	public int reduceToIntSequentially
3525	>	(ToIntBiFunction<? super K, ? super V> transformer,
3526	>	int basis,
3527	>	IntBinaryOperator reducer) {
3528	>	if (transformer == null || reducer == null)
3529	>	throw new NullPointerException();
3530	>	Traverser<K,V,Object> it = new Traverser<K,V,Object>(this);
3531	>	int r = basis; V v;
3532	>	while ((v = it.advanceValue()) != null)
3533	>	r = reducer.applyAsInt(r, transformer.applyAsInt(it.nextKey, v));
3534	>	return r;
3535	>	}
3536	>
3537	>	/**
3538	>	* Performs the given action for each key.
3539	>	*
3540	>	* @param action the action
3541	>	*/
3542	>	public void forEachKeySequentially
3543	>	(Consumer<? super K> action) {
3544	>	new Traverser<K,V,Object>(this).forEachKey(action);
3545	>	}
3546	>
3547	>	/**
3548	>	* Performs the given action for each non-null transformation
3549	>	* of each key.
3550	>	*
3551	>	* @param transformer a function returning the transformation
3552	>	* for an element, or null if there is no transformation (in
3553	>	* which case the action is not applied)
3554	>	* @param action the action
3555	>	*/
3556	>	public <U> void forEachKeySequentially
3557	>	(Function<? super K, ? extends U> transformer,
3558	>	Consumer<? super U> action) {
3559	>	if (transformer == null || action == null)
3560	>	throw new NullPointerException();
3561	>	Traverser<K,V,Object> it = new Traverser<K,V,Object>(this);
3562	>	K k; U u;
3563	>	while ((k = it.advanceKey()) != null) {
3564	>	if ((u = transformer.apply(k)) != null)
3565	>	action.accept(u);
3566		}
3567	<	public <T> T[] toArray(T[] a) {
3568	<	Collection<K> c = new ArrayList<K>();
3569	<	for (K k : this)
3570	<	c.add(k);
3571	<	return c.toArray(a);
3567	>	ForkJoinTasks.forEachKey
3568	>	(this, transformer, action).invoke();
3569	>	}
3570	>
3571	>	/**
3572	>	* Returns a non-null result from applying the given search
3573	>	* function on each key, or null if none.
3574	>	*
3575	>	* @param searchFunction a function returning a non-null
3576	>	* result on success, else null
3577	>	* @return a non-null result from applying the given search
3578	>	* function on each key, or null if none
3579	>	*/
3580	>	public <U> U searchKeysSequentially
3581	>	(Function<? super K, ? extends U> searchFunction) {
3582	>	Traverser<K,V,Object> it = new Traverser<K,V,Object>(this);
3583	>	K k; U u;
3584	>	while ((k = it.advanceKey()) != null) {
3585	>	if ((u = searchFunction.apply(k)) != null)
3586	>	return u;
3587		}
3588	+	return null;
3589		}
3590
3591	<	final class Values extends AbstractCollection<V> {
3592	<	public Iterator<V> iterator() {
3593	<	return new ValueIterator();
3591	>	/**
3592	>	* Returns the result of accumulating all keys using the given
3593	>	* reducer to combine values, or null if none.
3594	>	*
3595	>	* @param reducer a commutative associative combining function
3596	>	* @return the result of accumulating all keys using the given
3597	>	* reducer to combine values, or null if none
3598	>	*/
3599	>	public K reduceKeysSequentially
3600	>	(BiFunction<? super K, ? super K, ? extends K> reducer) {
3601	>	if (reducer == null) throw new NullPointerException();
3602	>	Traverser<K,V,Object> it = new Traverser<K,V,Object>(this);
3603	>	K u, r = null;
3604	>	while ((u = it.advanceKey()) != null) {
3605	>	r = (r == null) ? u : reducer.apply(r, u);
3606		}
3607	<	public int size() {
3608	<	return ConcurrentHashMap.this.size();
3607	>	return r;
3608	>	}
3609	>
3610	>	/**
3611	>	* Returns the result of accumulating the given transformation
3612	>	* of all keys using the given reducer to combine values, or
3613	>	* null if none.
3614	>	*
3615	>	* @param transformer a function returning the transformation
3616	>	* for an element, or null if there is no transformation (in
3617	>	* which case it is not combined)
3618	>	* @param reducer a commutative associative combining function
3619	>	* @return the result of accumulating the given transformation
3620	>	* of all keys
3621	>	*/
3622	>	public <U> U reduceKeysSequentially
3623	>	(Function<? super K, ? extends U> transformer,
3624	>	BiFunction<? super U, ? super U, ? extends U> reducer) {
3625	>	if (transformer == null || reducer == null)
3626	>	throw new NullPointerException();
3627	>	Traverser<K,V,Object> it = new Traverser<K,V,Object>(this);
3628	>	K k; U r = null, u;
3629	>	while ((k = it.advanceKey()) != null) {
3630	>	if ((u = transformer.apply(k)) != null)
3631	>	r = (r == null) ? u : reducer.apply(r, u);
3632		}
3633	<	public boolean contains(Object o) {
3634	<	return ConcurrentHashMap.this.containsValue(o);
3633	>	return r;
3634	>	}
3635	>
3636	>	/**
3637	>	* Returns the result of accumulating the given transformation
3638	>	* of all keys using the given reducer to combine values, and
3639	>	* the given basis as an identity value.
3640	>	*
3641	>	* @param transformer a function returning the transformation
3642	>	* for an element
3643	>	* @param basis the identity (initial default value) for the reduction
3644	>	* @param reducer a commutative associative combining function
3645	>	* @return the result of accumulating the given transformation
3646	>	* of all keys
3647	>	*/
3648	>	public double reduceKeysToDoubleSequentially
3649	>	(ToDoubleFunction<? super K> transformer,
3650	>	double basis,
3651	>	DoubleBinaryOperator reducer) {
3652	>	if (transformer == null || reducer == null)
3653	>	throw new NullPointerException();
3654	>	Traverser<K,V,Object> it = new Traverser<K,V,Object>(this);
3655	>	double r = basis;
3656	>	K k;
3657	>	while ((k = it.advanceKey()) != null)
3658	>	r = reducer.applyAsDouble(r, transformer.applyAsDouble(k));
3659	>	return r;
3660	>	}
3661	>
3662	>	/**
3663	>	* Returns the result of accumulating the given transformation
3664	>	* of all keys using the given reducer to combine values, and
3665	>	* the given basis as an identity value.
3666	>	*
3667	>	* @param transformer a function returning the transformation
3668	>	* for an element
3669	>	* @param basis the identity (initial default value) for the reduction
3670	>	* @param reducer a commutative associative combining function
3671	>	* @return the result of accumulating the given transformation
3672	>	* of all keys
3673	>	*/
3674	>	public long reduceKeysToLongSequentially
3675	>	(ToLongFunction<? super K> transformer,
3676	>	long basis,
3677	>	LongBinaryOperator reducer) {
3678	>	if (transformer == null || reducer == null)
3679	>	throw new NullPointerException();
3680	>	Traverser<K,V,Object> it = new Traverser<K,V,Object>(this);
3681	>	long r = basis;
3682	>	K k;
3683	>	while ((k = it.advanceKey()) != null)
3684	>	r = reducer.applyAsLong(r, transformer.applyAsLong(k));
3685	>	return r;
3686	>	}
3687	>
3688	>	/**
3689	>	* Returns the result of accumulating the given transformation
3690	>	* of all keys using the given reducer to combine values, and
3691	>	* the given basis as an identity value.
3692	>	*
3693	>	* @param transformer a function returning the transformation
3694	>	* for an element
3695	>	* @param basis the identity (initial default value) for the reduction
3696	>	* @param reducer a commutative associative combining function
3697	>	* @return the result of accumulating the given transformation
3698	>	* of all keys
3699	>	*/
3700	>	public int reduceKeysToIntSequentially
3701	>	(ToIntFunction<? super K> transformer,
3702	>	int basis,
3703	>	IntBinaryOperator reducer) {
3704	>	if (transformer == null || reducer == null)
3705	>	throw new NullPointerException();
3706	>	Traverser<K,V,Object> it = new Traverser<K,V,Object>(this);
3707	>	int r = basis;
3708	>	K k;
3709	>	while ((k = it.advanceKey()) != null)
3710	>	r = reducer.applyAsInt(r, transformer.applyAsInt(k));
3711	>	return r;
3712	>	}
3713	>
3714	>	/**
3715	>	* Performs the given action for each value.
3716	>	*
3717	>	* @param action the action
3718	>	*/
3719	>	public void forEachValueSequentially(Consumer<? super V> action) {
3720	>	new Traverser<K,V,Object>(this).forEachValue(action);
3721	>	}
3722	>
3723	>	/**
3724	>	* Performs the given action for each non-null transformation
3725	>	* of each value.
3726	>	*
3727	>	* @param transformer a function returning the transformation
3728	>	* for an element, or null if there is no transformation (in
3729	>	* which case the action is not applied)
3730	>	* @param action the action
3731	>	*/
3732	>	public <U> void forEachValueSequentially
3733	>	(Function<? super V, ? extends U> transformer,
3734	>	Consumer<? super U> action) {
3735	>	if (transformer == null || action == null)
3736	>	throw new NullPointerException();
3737	>	Traverser<K,V,Object> it = new Traverser<K,V,Object>(this);
3738	>	V v; U u;
3739	>	while ((v = it.advanceValue()) != null) {
3740	>	if ((u = transformer.apply(v)) != null)
3741	>	action.accept(u);
3742		}
3743	<	public void clear() {
3744	<	ConcurrentHashMap.this.clear();
3743	>	}
3744	>
3745	>	/**
3746	>	* Returns a non-null result from applying the given search
3747	>	* function on each value, or null if none.
3748	>	*
3749	>	* @param searchFunction a function returning a non-null
3750	>	* result on success, else null
3751	>	* @return a non-null result from applying the given search
3752	>	* function on each value, or null if none
3753	>	*/
3754	>	public <U> U searchValuesSequentially
3755	>	(Function<? super V, ? extends U> searchFunction) {
3756	>	if (searchFunction == null) throw new NullPointerException();
3757	>	Traverser<K,V,Object> it = new Traverser<K,V,Object>(this);
3758	>	V v; U u;
3759	>	while ((v = it.advanceValue()) != null) {
3760	>	if ((u = searchFunction.apply(v)) != null)
3761	>	return u;
3762		}
3763	<	public Object[] toArray() {
3764	<	Collection<V> c = new ArrayList<V>(size());
3765	<	for (V v : this)
3766	<	c.add(v);
3767	<	return c.toArray();
3763	>	return null;
3764	>	}
3765	>
3766	>	/**
3767	>	* Returns the result of accumulating all values using the
3768	>	* given reducer to combine values, or null if none.
3769	>	*
3770	>	* @param reducer a commutative associative combining function
3771	>	* @return the result of accumulating all values
3772	>	*/
3773	>	public V reduceValuesSequentially
3774	>	(BiFunction<? super V, ? super V, ? extends V> reducer) {
3775	>	if (reducer == null) throw new NullPointerException();
3776	>	Traverser<K,V,Object> it = new Traverser<K,V,Object>(this);
3777	>	V r = null; V v;
3778	>	while ((v = it.advanceValue()) != null)
3779	>	r = (r == null) ? v : reducer.apply(r, v);
3780	>	return r;
3781	>	}
3782	>
3783	>	/**
3784	>	* Returns the result of accumulating the given transformation
3785	>	* of all values using the given reducer to combine values, or
3786	>	* null if none.
3787	>	*
3788	>	* @param transformer a function returning the transformation
3789	>	* for an element, or null if there is no transformation (in
3790	>	* which case it is not combined)
3791	>	* @param reducer a commutative associative combining function
3792	>	* @return the result of accumulating the given transformation
3793	>	* of all values
3794	>	*/
3795	>	public <U> U reduceValuesSequentially
3796	>	(Function<? super V, ? extends U> transformer,
3797	>	BiFunction<? super U, ? super U, ? extends U> reducer) {
3798	>	if (transformer == null || reducer == null)
3799	>	throw new NullPointerException();
3800	>	Traverser<K,V,Object> it = new Traverser<K,V,Object>(this);
3801	>	U r = null, u; V v;
3802	>	while ((v = it.advanceValue()) != null) {
3803	>	if ((u = transformer.apply(v)) != null)
3804	>	r = (r == null) ? u : reducer.apply(r, u);
3805		}
3806	<	public <T> T[] toArray(T[] a) {
3807	<	Collection<V> c = new ArrayList<V>(size());
3808	<	for (V v : this)
3809	<	c.add(v);
3810	<	return c.toArray(a);
3806	>	return r;
3807	>	}
3808	>
3809	>	/**
3810	>	* Returns the result of accumulating the given transformation
3811	>	* of all values using the given reducer to combine values,
3812	>	* and the given basis as an identity value.
3813	>	*
3814	>	* @param transformer a function returning the transformation
3815	>	* for an element
3816	>	* @param basis the identity (initial default value) for the reduction
3817	>	* @param reducer a commutative associative combining function
3818	>	* @return the result of accumulating the given transformation
3819	>	* of all values
3820	>	*/
3821	>	public double reduceValuesToDoubleSequentially
3822	>	(ToDoubleFunction<? super V> transformer,
3823	>	double basis,
3824	>	DoubleBinaryOperator reducer) {
3825	>	if (transformer == null || reducer == null)
3826	>	throw new NullPointerException();
3827	>	Traverser<K,V,Object> it = new Traverser<K,V,Object>(this);
3828	>	double r = basis; V v;
3829	>	while ((v = it.advanceValue()) != null)
3830	>	r = reducer.applyAsDouble(r, transformer.applyAsDouble(v));
3831	>	return r;
3832	>	}
3833	>
3834	>	/**
3835	>	* Returns the result of accumulating the given transformation
3836	>	* of all values using the given reducer to combine values,
3837	>	* and the given basis as an identity value.
3838	>	*
3839	>	* @param transformer a function returning the transformation
3840	>	* for an element
3841	>	* @param basis the identity (initial default value) for the reduction
3842	>	* @param reducer a commutative associative combining function
3843	>	* @return the result of accumulating the given transformation
3844	>	* of all values
3845	>	*/
3846	>	public long reduceValuesToLongSequentially
3847	>	(ToLongFunction<? super V> transformer,
3848	>	long basis,
3849	>	LongBinaryOperator reducer) {
3850	>	if (transformer == null || reducer == null)
3851	>	throw new NullPointerException();
3852	>	Traverser<K,V,Object> it = new Traverser<K,V,Object>(this);
3853	>	long r = basis; V v;
3854	>	while ((v = it.advanceValue()) != null)
3855	>	r = reducer.applyAsLong(r, transformer.applyAsLong(v));
3856	>	return r;
3857	>	}
3858	>
3859	>	/**
3860	>	* Returns the result of accumulating the given transformation
3861	>	* of all values using the given reducer to combine values,
3862	>	* and the given basis as an identity value.
3863	>	*
3864	>	* @param transformer a function returning the transformation
3865	>	* for an element
3866	>	* @param basis the identity (initial default value) for the reduction
3867	>	* @param reducer a commutative associative combining function
3868	>	* @return the result of accumulating the given transformation
3869	>	* of all values
3870	>	*/
3871	>	public int reduceValuesToIntSequentially
3872	>	(ToIntFunction<? super V> transformer,
3873	>	int basis,
3874	>	IntBinaryOperator reducer) {
3875	>	if (transformer == null || reducer == null)
3876	>	throw new NullPointerException();
3877	>	Traverser<K,V,Object> it = new Traverser<K,V,Object>(this);
3878	>	int r = basis; V v;
3879	>	while ((v = it.advanceValue()) != null)
3880	>	r = reducer.applyAsInt(r, transformer.applyAsInt(v));
3881	>	return r;
3882	>	}
3883	>
3884	>	/**
3885	>	* Performs the given action for each entry.
3886	>	*
3887	>	* @param action the action
3888	>	*/
3889	>	public void forEachEntrySequentially
3890	>	(Consumer<? super Map.Entry<K,V>> action) {
3891	>	if (action == null) throw new NullPointerException();
3892	>	Traverser<K,V,Object> it = new Traverser<K,V,Object>(this);
3893	>	V v;
3894	>	while ((v = it.advanceValue()) != null)
3895	>	action.accept(entryFor(it.nextKey, v));
3896	>	}
3897	>
3898	>	/**
3899	>	* Performs the given action for each non-null transformation
3900	>	* of each entry.
3901	>	*
3902	>	* @param transformer a function returning the transformation
3903	>	* for an element, or null if there is no transformation (in
3904	>	* which case the action is not applied)
3905	>	* @param action the action
3906	>	*/
3907	>	public <U> void forEachEntrySequentially
3908	>	(Function<Map.Entry<K,V>, ? extends U> transformer,
3909	>	Consumer<? super U> action) {
3910	>	if (transformer == null || action == null)
3911	>	throw new NullPointerException();
3912	>	Traverser<K,V,Object> it = new Traverser<K,V,Object>(this);
3913	>	V v; U u;
3914	>	while ((v = it.advanceValue()) != null) {
3915	>	if ((u = transformer.apply(entryFor(it.nextKey, v))) != null)
3916	>	action.accept(u);
3917		}
3918		}
3919
3920	<	final class EntrySet extends AbstractSet<Map.Entry<K,V>> {
3921	<	public Iterator<Map.Entry<K,V>> iterator() {
3922	<	return new EntryIterator();
3920	>	/**
3921	>	* Returns a non-null result from applying the given search
3922	>	* function on each entry, or null if none.
3923	>	*
3924	>	* @param searchFunction a function returning a non-null
3925	>	* result on success, else null
3926	>	* @return a non-null result from applying the given search
3927	>	* function on each entry, or null if none
3928	>	*/
3929	>	public <U> U searchEntriesSequentially
3930	>	(Function<Map.Entry<K,V>, ? extends U> searchFunction) {
3931	>	if (searchFunction == null) throw new NullPointerException();
3932	>	Traverser<K,V,Object> it = new Traverser<K,V,Object>(this);
3933	>	V v; U u;
3934	>	while ((v = it.advanceValue()) != null) {
3935	>	if ((u = searchFunction.apply(entryFor(it.nextKey, v))) != null)
3936	>	return u;
3937		}
3938	<	public boolean contains(Object o) {
3939	<	if (!(o instanceof Map.Entry))
3940	<	return false;
3941	<	Map.Entry<?,?> e = (Map.Entry<?,?>)o;
3942	<	V v = ConcurrentHashMap.this.get(e.getKey());
3943	<	return v != null && v.equals(e.getValue());
3938	>	return null;
3939	>	}
3940	>
3941	>	/**
3942	>	* Returns the result of accumulating all entries using the
3943	>	* given reducer to combine values, or null if none.
3944	>	*
3945	>	* @param reducer a commutative associative combining function
3946	>	* @return the result of accumulating all entries
3947	>	*/
3948	>	public Map.Entry<K,V> reduceEntriesSequentially
3949	>	(BiFunction<Map.Entry<K,V>, Map.Entry<K,V>, ? extends Map.Entry<K,V>> reducer) {
3950	>	if (reducer == null) throw new NullPointerException();
3951	>	Traverser<K,V,Object> it = new Traverser<K,V,Object>(this);
3952	>	Map.Entry<K,V> r = null; V v;
3953	>	while ((v = it.advanceValue()) != null) {
3954	>	Map.Entry<K,V> u = entryFor(it.nextKey, v);
3955	>	r = (r == null) ? u : reducer.apply(r, u);
3956		}
3957	<	public boolean remove(Object o) {
3958	<	if (!(o instanceof Map.Entry))
3959	<	return false;
3960	<	Map.Entry<?,?> e = (Map.Entry<?,?>)o;
3961	<	return ConcurrentHashMap.this.remove(e.getKey(), e.getValue());
3957	>	return r;
3958	>	}
3959	>
3960	>	/**
3961	>	* Returns the result of accumulating the given transformation
3962	>	* of all entries using the given reducer to combine values,
3963	>	* or null if none.
3964	>	*
3965	>	* @param transformer a function returning the transformation
3966	>	* for an element, or null if there is no transformation (in
3967	>	* which case it is not combined)
3968	>	* @param reducer a commutative associative combining function
3969	>	* @return the result of accumulating the given transformation
3970	>	* of all entries
3971	>	*/
3972	>	public <U> U reduceEntriesSequentially
3973	>	(Function<Map.Entry<K,V>, ? extends U> transformer,
3974	>	BiFunction<? super U, ? super U, ? extends U> reducer) {
3975	>	if (transformer == null || reducer == null)
3976	>	throw new NullPointerException();
3977	>	Traverser<K,V,Object> it = new Traverser<K,V,Object>(this);
3978	>	U r = null, u; V v;
3979	>	while ((v = it.advanceValue()) != null) {
3980	>	if ((u = transformer.apply(entryFor(it.nextKey, v))) != null)
3981	>	r = (r == null) ? u : reducer.apply(r, u);
3982		}
3983	<	public int size() {
3984	<	return ConcurrentHashMap.this.size();
3983	>	return r;
3984	>	}
3985	>
3986	>	/**
3987	>	* Returns the result of accumulating the given transformation
3988	>	* of all entries using the given reducer to combine values,
3989	>	* and the given basis as an identity value.
3990	>	*
3991	>	* @param transformer a function returning the transformation
3992	>	* for an element
3993	>	* @param basis the identity (initial default value) for the reduction
3994	>	* @param reducer a commutative associative combining function
3995	>	* @return the result of accumulating the given transformation
3996	>	* of all entries
3997	>	*/
3998	>	public double reduceEntriesToDoubleSequentially
3999	>	(ToDoubleFunction<Map.Entry<K,V>> transformer,
4000	>	double basis,
4001	>	DoubleBinaryOperator reducer) {
4002	>	if (transformer == null || reducer == null)
4003	>	throw new NullPointerException();
4004	>	Traverser<K,V,Object> it = new Traverser<K,V,Object>(this);
4005	>	double r = basis; V v;
4006	>	while ((v = it.advanceValue()) != null)
4007	>	r = reducer.applyAsDouble(r, transformer.applyAsDouble(entryFor(it.nextKey, v)));
4008	>	return r;
4009	>	}
4010	>
4011	>	/**
4012	>	* Returns the result of accumulating the given transformation
4013	>	* of all entries using the given reducer to combine values,
4014	>	* and the given basis as an identity value.
4015	>	*
4016	>	* @param transformer a function returning the transformation
4017	>	* for an element
4018	>	* @param basis the identity (initial default value) for the reduction
4019	>	* @param reducer a commutative associative combining function
4020	>	* @return the result of accumulating the given transformation
4021	>	* of all entries
4022	>	*/
4023	>	public long reduceEntriesToLongSequentially
4024	>	(ToLongFunction<Map.Entry<K,V>> transformer,
4025	>	long basis,
4026	>	LongBinaryOperator reducer) {
4027	>	if (transformer == null || reducer == null)
4028	>	throw new NullPointerException();
4029	>	Traverser<K,V,Object> it = new Traverser<K,V,Object>(this);
4030	>	long r = basis; V v;
4031	>	while ((v = it.advanceValue()) != null)
4032	>	r = reducer.applyAsLong(r, transformer.applyAsLong(entryFor(it.nextKey, v)));
4033	>	return r;
4034	>	}
4035	>
4036	>	/**
4037	>	* Returns the result of accumulating the given transformation
4038	>	* of all entries using the given reducer to combine values,
4039	>	* and the given basis as an identity value.
4040	>	*
4041	>	* @param transformer a function returning the transformation
4042	>	* for an element
4043	>	* @param basis the identity (initial default value) for the reduction
4044	>	* @param reducer a commutative associative combining function
4045	>	* @return the result of accumulating the given transformation
4046	>	* of all entries
4047	>	*/
4048	>	public int reduceEntriesToIntSequentially
4049	>	(ToIntFunction<Map.Entry<K,V>> transformer,
4050	>	int basis,
4051	>	IntBinaryOperator reducer) {
4052	>	if (transformer == null || reducer == null)
4053	>	throw new NullPointerException();
4054	>	Traverser<K,V,Object> it = new Traverser<K,V,Object>(this);
4055	>	int r = basis; V v;
4056	>	while ((v = it.advanceValue()) != null)
4057	>	r = reducer.applyAsInt(r, transformer.applyAsInt(entryFor(it.nextKey, v)));
4058	>	return r;
4059	>	}
4060	>
4061	>	// Parallel bulk operations
4062	>
4063	>	/**
4064	>	* Performs the given action for each (key, value).
4065	>	*
4066	>	* @param action the action
4067	>	*/
4068	>	public void forEachInParallel(BiConsumer<? super K,? super V> action) {
4069	>	ForkJoinTasks.forEach
4070	>	(this, action).invoke();
4071	>	}
4072	>
4073	>	/**
4074	>	* Performs the given action for each non-null transformation
4075	>	* of each (key, value).
4076	>	*
4077	>	* @param transformer a function returning the transformation
4078	>	* for an element, or null if there is no transformation (in
4079	>	* which case the action is not applied)
4080	>	* @param action the action
4081	>	*/
4082	>	public <U> void forEachInParallel
4083	>	(BiFunction<? super K, ? super V, ? extends U> transformer,
4084	>	Consumer<? super U> action) {
4085	>	ForkJoinTasks.forEach
4086	>	(this, transformer, action).invoke();
4087	>	}
4088	>
4089	>	/**
4090	>	* Returns a non-null result from applying the given search
4091	>	* function on each (key, value), or null if none.  Upon
4092	>	* success, further element processing is suppressed and the
4093	>	* results of any other parallel invocations of the search
4094	>	* function are ignored.
4095	>	*
4096	>	* @param searchFunction a function returning a non-null
4097	>	* result on success, else null
4098	>	* @return a non-null result from applying the given search
4099	>	* function on each (key, value), or null if none
4100	>	*/
4101	>	public <U> U searchInParallel
4102	>	(BiFunction<? super K, ? super V, ? extends U> searchFunction) {
4103	>	return ForkJoinTasks.search
4104	>	(this, searchFunction).invoke();
4105	>	}
4106	>
4107	>	/**
4108	>	* Returns the result of accumulating the given transformation
4109	>	* of all (key, value) pairs using the given reducer to
4110	>	* combine values, or null if none.
4111	>	*
4112	>	* @param transformer a function returning the transformation
4113	>	* for an element, or null if there is no transformation (in
4114	>	* which case it is not combined)
4115	>	* @param reducer a commutative associative combining function
4116	>	* @return the result of accumulating the given transformation
4117	>	* of all (key, value) pairs
4118	>	*/
4119	>	public <U> U reduceInParallel
4120	>	(BiFunction<? super K, ? super V, ? extends U> transformer,
4121	>	BiFunction<? super U, ? super U, ? extends U> reducer) {
4122	>	return ForkJoinTasks.reduce
4123	>	(this, transformer, reducer).invoke();
4124	>	}
4125	>
4126	>	/**
4127	>	* Returns the result of accumulating the given transformation
4128	>	* of all (key, value) pairs using the given reducer to
4129	>	* combine values, and the given basis as an identity value.
4130	>	*
4131	>	* @param transformer a function returning the transformation
4132	>	* for an element
4133	>	* @param basis the identity (initial default value) for the reduction
4134	>	* @param reducer a commutative associative combining function
4135	>	* @return the result of accumulating the given transformation
4136	>	* of all (key, value) pairs
4137	>	*/
4138	>	public double reduceToDoubleInParallel
4139	>	(ToDoubleBiFunction<? super K, ? super V> transformer,
4140	>	double basis,
4141	>	DoubleBinaryOperator reducer) {
4142	>	return ForkJoinTasks.reduceToDouble
4143	>	(this, transformer, basis, reducer).invoke();
4144	>	}
4145	>
4146	>	/**
4147	>	* Returns the result of accumulating the given transformation
4148	>	* of all (key, value) pairs using the given reducer to
4149	>	* combine values, and the given basis as an identity value.
4150	>	*
4151	>	* @param transformer a function returning the transformation
4152	>	* for an element
4153	>	* @param basis the identity (initial default value) for the reduction
4154	>	* @param reducer a commutative associative combining function
4155	>	* @return the result of accumulating the given transformation
4156	>	* of all (key, value) pairs
4157	>	*/
4158	>	public long reduceToLongInParallel
4159	>	(ToLongBiFunction<? super K, ? super V> transformer,
4160	>	long basis,
4161	>	LongBinaryOperator reducer) {
4162	>	return ForkJoinTasks.reduceToLong
4163	>	(this, transformer, basis, reducer).invoke();
4164	>	}
4165	>
4166	>	/**
4167	>	* Returns the result of accumulating the given transformation
4168	>	* of all (key, value) pairs using the given reducer to
4169	>	* combine values, and the given basis as an identity value.
4170	>	*
4171	>	* @param transformer a function returning the transformation
4172	>	* for an element
4173	>	* @param basis the identity (initial default value) for the reduction
4174	>	* @param reducer a commutative associative combining function
4175	>	* @return the result of accumulating the given transformation
4176	>	* of all (key, value) pairs
4177	>	*/
4178	>	public int reduceToIntInParallel
4179	>	(ToIntBiFunction<? super K, ? super V> transformer,
4180	>	int basis,
4181	>	IntBinaryOperator reducer) {
4182	>	return ForkJoinTasks.reduceToInt
4183	>	(this, transformer, basis, reducer).invoke();
4184	>	}
4185	>
4186	>	/**
4187	>	* Performs the given action for each key.
4188	>	*
4189	>	* @param action the action
4190	>	*/
4191	>	public void forEachKeyInParallel(Consumer<? super K> action) {
4192	>	ForkJoinTasks.forEachKey
4193	>	(this, action).invoke();
4194	>	}
4195	>
4196	>	/**
4197	>	* Performs the given action for each non-null transformation
4198	>	* of each key.
4199	>	*
4200	>	* @param transformer a function returning the transformation
4201	>	* for an element, or null if there is no transformation (in
4202	>	* which case the action is not applied)
4203	>	* @param action the action
4204	>	*/
4205	>	public <U> void forEachKeyInParallel
4206	>	(Function<? super K, ? extends U> transformer,
4207	>	Consumer<? super U> action) {
4208	>	ForkJoinTasks.forEachKey
4209	>	(this, transformer, action).invoke();
4210	>	}
4211	>
4212	>	/**
4213	>	* Returns a non-null result from applying the given search
4214	>	* function on each key, or null if none. Upon success,
4215	>	* further element processing is suppressed and the results of
4216	>	* any other parallel invocations of the search function are
4217	>	* ignored.
4218	>	*
4219	>	* @param searchFunction a function returning a non-null
4220	>	* result on success, else null
4221	>	* @return a non-null result from applying the given search
4222	>	* function on each key, or null if none
4223	>	*/
4224	>	public <U> U searchKeysInParallel
4225	>	(Function<? super K, ? extends U> searchFunction) {
4226	>	return ForkJoinTasks.searchKeys
4227	>	(this, searchFunction).invoke();
4228	>	}
4229	>
4230	>	/**
4231	>	* Returns the result of accumulating all keys using the given
4232	>	* reducer to combine values, or null if none.
4233	>	*
4234	>	* @param reducer a commutative associative combining function
4235	>	* @return the result of accumulating all keys using the given
4236	>	* reducer to combine values, or null if none
4237	>	*/
4238	>	public K reduceKeysInParallel
4239	>	(BiFunction<? super K, ? super K, ? extends K> reducer) {
4240	>	return ForkJoinTasks.reduceKeys
4241	>	(this, reducer).invoke();
4242	>	}
4243	>
4244	>	/**
4245	>	* Returns the result of accumulating the given transformation
4246	>	* of all keys using the given reducer to combine values, or
4247	>	* null if none.
4248	>	*
4249	>	* @param transformer a function returning the transformation
4250	>	* for an element, or null if there is no transformation (in
4251	>	* which case it is not combined)
4252	>	* @param reducer a commutative associative combining function
4253	>	* @return the result of accumulating the given transformation
4254	>	* of all keys
4255	>	*/
4256	>	public <U> U reduceKeysInParallel
4257	>	(Function<? super K, ? extends U> transformer,
4258	>	BiFunction<? super U, ? super U, ? extends U> reducer) {
4259	>	return ForkJoinTasks.reduceKeys
4260	>	(this, transformer, reducer).invoke();
4261	>	}
4262	>
4263	>	/**
4264	>	* Returns the result of accumulating the given transformation
4265	>	* of all keys using the given reducer to combine values, and
4266	>	* the given basis as an identity value.
4267	>	*
4268	>	* @param transformer a function returning the transformation
4269	>	* for an element
4270	>	* @param basis the identity (initial default value) for the reduction
4271	>	* @param reducer a commutative associative combining function
4272	>	* @return the result of accumulating the given transformation
4273	>	* of all keys
4274	>	*/
4275	>	public double reduceKeysToDoubleInParallel
4276	>	(ToDoubleFunction<? super K> transformer,
4277	>	double basis,
4278	>	DoubleBinaryOperator reducer) {
4279	>	return ForkJoinTasks.reduceKeysToDouble
4280	>	(this, transformer, basis, reducer).invoke();
4281	>	}
4282	>
4283	>	/**
4284	>	* Returns the result of accumulating the given transformation
4285	>	* of all keys using the given reducer to combine values, and
4286	>	* the given basis as an identity value.
4287	>	*
4288	>	* @param transformer a function returning the transformation
4289	>	* for an element
4290	>	* @param basis the identity (initial default value) for the reduction
4291	>	* @param reducer a commutative associative combining function
4292	>	* @return the result of accumulating the given transformation
4293	>	* of all keys
4294	>	*/
4295	>	public long reduceKeysToLongInParallel
4296	>	(ToLongFunction<? super K> transformer,
4297	>	long basis,
4298	>	LongBinaryOperator reducer) {
4299	>	return ForkJoinTasks.reduceKeysToLong
4300	>	(this, transformer, basis, reducer).invoke();
4301	>	}
4302	>
4303	>	/**
4304	>	* Returns the result of accumulating the given transformation
4305	>	* of all keys using the given reducer to combine values, and
4306	>	* the given basis as an identity value.
4307	>	*
4308	>	* @param transformer a function returning the transformation
4309	>	* for an element
4310	>	* @param basis the identity (initial default value) for the reduction
4311	>	* @param reducer a commutative associative combining function
4312	>	* @return the result of accumulating the given transformation
4313	>	* of all keys
4314	>	*/
4315	>	public int reduceKeysToIntInParallel
4316	>	(ToIntFunction<? super K> transformer,
4317	>	int basis,
4318	>	IntBinaryOperator reducer) {
4319	>	return ForkJoinTasks.reduceKeysToInt
4320	>	(this, transformer, basis, reducer).invoke();
4321	>	}
4322	>
4323	>	/**
4324	>	* Performs the given action for each value.
4325	>	*
4326	>	* @param action the action
4327	>	*/
4328	>	public void forEachValueInParallel(Consumer<? super V> action) {
4329	>	ForkJoinTasks.forEachValue
4330	>	(this, action).invoke();
4331	>	}
4332	>
4333	>	/**
4334	>	* Performs the given action for each non-null transformation
4335	>	* of each value.
4336	>	*
4337	>	* @param transformer a function returning the transformation
4338	>	* for an element, or null if there is no transformation (in
4339	>	* which case the action is not applied)
4340	>	* @param action the action
4341	>	*/
4342	>	public <U> void forEachValueInParallel
4343	>	(Function<? super V, ? extends U> transformer,
4344	>	Consumer<? super U> action) {
4345	>	ForkJoinTasks.forEachValue
4346	>	(this, transformer, action).invoke();
4347	>	}
4348	>
4349	>	/**
4350	>	* Returns a non-null result from applying the given search
4351	>	* function on each value, or null if none.  Upon success,
4352	>	* further element processing is suppressed and the results of
4353	>	* any other parallel invocations of the search function are
4354	>	* ignored.
4355	>	*
4356	>	* @param searchFunction a function returning a non-null
4357	>	* result on success, else null
4358	>	* @return a non-null result from applying the given search
4359	>	* function on each value, or null if none
4360	>	*/
4361	>	public <U> U searchValuesInParallel
4362	>	(Function<? super V, ? extends U> searchFunction) {
4363	>	return ForkJoinTasks.searchValues
4364	>	(this, searchFunction).invoke();
4365	>	}
4366	>
4367	>	/**
4368	>	* Returns the result of accumulating all values using the
4369	>	* given reducer to combine values, or null if none.
4370	>	*
4371	>	* @param reducer a commutative associative combining function
4372	>	* @return the result of accumulating all values
4373	>	*/
4374	>	public V reduceValuesInParallel
4375	>	(BiFunction<? super V, ? super V, ? extends V> reducer) {
4376	>	return ForkJoinTasks.reduceValues
4377	>	(this, reducer).invoke();
4378	>	}
4379	>
4380	>	/**
4381	>	* Returns the result of accumulating the given transformation
4382	>	* of all values using the given reducer to combine values, or
4383	>	* null if none.
4384	>	*
4385	>	* @param transformer a function returning the transformation
4386	>	* for an element, or null if there is no transformation (in
4387	>	* which case it is not combined)
4388	>	* @param reducer a commutative associative combining function
4389	>	* @return the result of accumulating the given transformation
4390	>	* of all values
4391	>	*/
4392	>	public <U> U reduceValuesInParallel
4393	>	(Function<? super V, ? extends U> transformer,
4394	>	BiFunction<? super U, ? super U, ? extends U> reducer) {
4395	>	return ForkJoinTasks.reduceValues
4396	>	(this, transformer, reducer).invoke();
4397	>	}
4398	>
4399	>	/**
4400	>	* Returns the result of accumulating the given transformation
4401	>	* of all values using the given reducer to combine values,
4402	>	* and the given basis as an identity value.
4403	>	*
4404	>	* @param transformer a function returning the transformation
4405	>	* for an element
4406	>	* @param basis the identity (initial default value) for the reduction
4407	>	* @param reducer a commutative associative combining function
4408	>	* @return the result of accumulating the given transformation
4409	>	* of all values
4410	>	*/
4411	>	public double reduceValuesToDoubleInParallel
4412	>	(ToDoubleFunction<? super V> transformer,
4413	>	double basis,
4414	>	DoubleBinaryOperator reducer) {
4415	>	return ForkJoinTasks.reduceValuesToDouble
4416	>	(this, transformer, basis, reducer).invoke();
4417	>	}
4418	>
4419	>	/**
4420	>	* Returns the result of accumulating the given transformation
4421	>	* of all values using the given reducer to combine values,
4422	>	* and the given basis as an identity value.
4423	>	*
4424	>	* @param transformer a function returning the transformation
4425	>	* for an element
4426	>	* @param basis the identity (initial default value) for the reduction
4427	>	* @param reducer a commutative associative combining function
4428	>	* @return the result of accumulating the given transformation
4429	>	* of all values
4430	>	*/
4431	>	public long reduceValuesToLongInParallel
4432	>	(ToLongFunction<? super V> transformer,
4433	>	long basis,
4434	>	LongBinaryOperator reducer) {
4435	>	return ForkJoinTasks.reduceValuesToLong
4436	>	(this, transformer, basis, reducer).invoke();
4437	>	}
4438	>
4439	>	/**
4440	>	* Returns the result of accumulating the given transformation
4441	>	* of all values using the given reducer to combine values,
4442	>	* and the given basis as an identity value.
4443	>	*
4444	>	* @param transformer a function returning the transformation
4445	>	* for an element
4446	>	* @param basis the identity (initial default value) for the reduction
4447	>	* @param reducer a commutative associative combining function
4448	>	* @return the result of accumulating the given transformation
4449	>	* of all values
4450	>	*/
4451	>	public int reduceValuesToIntInParallel
4452	>	(ToIntFunction<? super V> transformer,
4453	>	int basis,
4454	>	IntBinaryOperator reducer) {
4455	>	return ForkJoinTasks.reduceValuesToInt
4456	>	(this, transformer, basis, reducer).invoke();
4457	>	}
4458	>
4459	>	/**
4460	>	* Performs the given action for each entry.
4461	>	*
4462	>	* @param action the action
4463	>	*/
4464	>	public void forEachEntryInParallel(Consumer<? super Map.Entry<K,V>> action) {
4465	>	ForkJoinTasks.forEachEntry
4466	>	(this, action).invoke();
4467	>	}
4468	>
4469	>	/**
4470	>	* Performs the given action for each non-null transformation
4471	>	* of each entry.
4472	>	*
4473	>	* @param transformer a function returning the transformation
4474	>	* for an element, or null if there is no transformation (in
4475	>	* which case the action is not applied)
4476	>	* @param action the action
4477	>	*/
4478	>	public <U> void forEachEntryInParallel
4479	>	(Function<Map.Entry<K,V>, ? extends U> transformer,
4480	>	Consumer<? super U> action) {
4481	>	ForkJoinTasks.forEachEntry
4482	>	(this, transformer, action).invoke();
4483	>	}
4484	>
4485	>	/**
4486	>	* Returns a non-null result from applying the given search
4487	>	* function on each entry, or null if none.  Upon success,
4488	>	* further element processing is suppressed and the results of
4489	>	* any other parallel invocations of the search function are
4490	>	* ignored.
4491	>	*
4492	>	* @param searchFunction a function returning a non-null
4493	>	* result on success, else null
4494	>	* @return a non-null result from applying the given search
4495	>	* function on each entry, or null if none
4496	>	*/
4497	>	public <U> U searchEntriesInParallel
4498	>	(Function<Map.Entry<K,V>, ? extends U> searchFunction) {
4499	>	return ForkJoinTasks.searchEntries
4500	>	(this, searchFunction).invoke();
4501	>	}
4502	>
4503	>	/**
4504	>	* Returns the result of accumulating all entries using the
4505	>	* given reducer to combine values, or null if none.
4506	>	*
4507	>	* @param reducer a commutative associative combining function
4508	>	* @return the result of accumulating all entries
4509	>	*/
4510	>	public Map.Entry<K,V> reduceEntriesInParallel
4511	>	(BiFunction<Map.Entry<K,V>, Map.Entry<K,V>, ? extends Map.Entry<K,V>> reducer) {
4512	>	return ForkJoinTasks.reduceEntries
4513	>	(this, reducer).invoke();
4514	>	}
4515	>
4516	>	/**
4517	>	* Returns the result of accumulating the given transformation
4518	>	* of all entries using the given reducer to combine values,
4519	>	* or null if none.
4520	>	*
4521	>	* @param transformer a function returning the transformation
4522	>	* for an element, or null if there is no transformation (in
4523	>	* which case it is not combined)
4524	>	* @param reducer a commutative associative combining function
4525	>	* @return the result of accumulating the given transformation
4526	>	* of all entries
4527	>	*/
4528	>	public <U> U reduceEntriesInParallel
4529	>	(Function<Map.Entry<K,V>, ? extends U> transformer,
4530	>	BiFunction<? super U, ? super U, ? extends U> reducer) {
4531	>	return ForkJoinTasks.reduceEntries
4532	>	(this, transformer, reducer).invoke();
4533	>	}
4534	>
4535	>	/**
4536	>	* Returns the result of accumulating the given transformation
4537	>	* of all entries using the given reducer to combine values,
4538	>	* and the given basis as an identity value.
4539	>	*
4540	>	* @param transformer a function returning the transformation
4541	>	* for an element
4542	>	* @param basis the identity (initial default value) for the reduction
4543	>	* @param reducer a commutative associative combining function
4544	>	* @return the result of accumulating the given transformation
4545	>	* of all entries
4546	>	*/
4547	>	public double reduceEntriesToDoubleInParallel
4548	>	(ToDoubleFunction<Map.Entry<K,V>> transformer,
4549	>	double basis,
4550	>	DoubleBinaryOperator reducer) {
4551	>	return ForkJoinTasks.reduceEntriesToDouble
4552	>	(this, transformer, basis, reducer).invoke();
4553	>	}
4554	>
4555	>	/**
4556	>	* Returns the result of accumulating the given transformation
4557	>	* of all entries using the given reducer to combine values,
4558	>	* and the given basis as an identity value.
4559	>	*
4560	>	* @param transformer a function returning the transformation
4561	>	* for an element
4562	>	* @param basis the identity (initial default value) for the reduction
4563	>	* @param reducer a commutative associative combining function
4564	>	* @return the result of accumulating the given transformation
4565	>	* of all entries
4566	>	*/
4567	>	public long reduceEntriesToLongInParallel
4568	>	(ToLongFunction<Map.Entry<K,V>> transformer,
4569	>	long basis,
4570	>	LongBinaryOperator reducer) {
4571	>	return ForkJoinTasks.reduceEntriesToLong
4572	>	(this, transformer, basis, reducer).invoke();
4573	>	}
4574	>
4575	>	/**
4576	>	* Returns the result of accumulating the given transformation
4577	>	* of all entries using the given reducer to combine values,
4578	>	* and the given basis as an identity value.
4579	>	*
4580	>	* @param transformer a function returning the transformation
4581	>	* for an element
4582	>	* @param basis the identity (initial default value) for the reduction
4583	>	* @param reducer a commutative associative combining function
4584	>	* @return the result of accumulating the given transformation
4585	>	* of all entries
4586	>	*/
4587	>	public int reduceEntriesToIntInParallel
4588	>	(ToIntFunction<Map.Entry<K,V>> transformer,
4589	>	int basis,
4590	>	IntBinaryOperator reducer) {
4591	>	return ForkJoinTasks.reduceEntriesToInt
4592	>	(this, transformer, basis, reducer).invoke();
4593	>	}
4594	>
4595	>
4596	>	/* ----------------Views -------------- */
4597	>
4598	>	/**
4599	>	* Base class for views.
4600	>	*/
4601	>	abstract static class CHMCollectionView<K,V,E>
4602	>	implements Collection<E>, java.io.Serializable {
4603	>	private static final long serialVersionUID = 7249069246763182397L;
4604	>	final ConcurrentHashMap<K,V> map;
4605	>	CHMCollectionView(ConcurrentHashMap<K,V> map)  { this.map = map; }
4606	>
4607	>	/**
4608	>	* Returns the map backing this view.
4609	>	*
4610	>	* @return the map backing this view
4611	>	*/
4612	>	public ConcurrentHashMap<K,V> getMap() { return map; }
4613	>
4614	>	/**
4615	>	* Removes all of the elements from this view, by removing all
4616	>	* the mappings from the map backing this view.
4617	>	*/
4618	>	public final void clear()      { map.clear(); }
4619	>	public final int size()        { return map.size(); }
4620	>	public final boolean isEmpty() { return map.isEmpty(); }
4621	>
4622	>	// implementations below rely on concrete classes supplying these
4623	>	// abstract methods
4624	>	/**
4625	>	* Returns a "weakly consistent" iterator that will never
4626	>	* throw {@link ConcurrentModificationException}, and
4627	>	* guarantees to traverse elements as they existed upon
4628	>	* construction of the iterator, and may (but is not
4629	>	* guaranteed to) reflect any modifications subsequent to
4630	>	* construction.
4631	>	*/
4632	>	public abstract Iterator<E> iterator();
4633	>	public abstract boolean contains(Object o);
4634	>	public abstract boolean remove(Object o);
4635	>
4636	>	private static final String oomeMsg = "Required array size too large";
4637	>
4638	>	public final Object[] toArray() {
4639	>	long sz = map.mappingCount();
4640	>	if (sz > MAX_ARRAY_SIZE)
4641	>	throw new OutOfMemoryError(oomeMsg);
4642	>	int n = (int)sz;
4643	>	Object[] r = new Object[n];
4644	>	int i = 0;
4645	>	for (E e : this) {
4646	>	if (i == n) {
4647	>	if (n >= MAX_ARRAY_SIZE)
4648	>	throw new OutOfMemoryError(oomeMsg);
4649	>	if (n >= MAX_ARRAY_SIZE - (MAX_ARRAY_SIZE >>> 1) - 1)
4650	>	n = MAX_ARRAY_SIZE;
4651	>	else
4652	>	n += (n >>> 1) + 1;
4653	>	r = Arrays.copyOf(r, n);
4654	>	}
4655	>	r[i++] = e;
4656	>	}
4657	>	return (i == n) ? r : Arrays.copyOf(r, i);
4658	>	}
4659	>
4660	>	@SuppressWarnings("unchecked")
4661	>	public final <T> T[] toArray(T[] a) {
4662	>	long sz = map.mappingCount();
4663	>	if (sz > MAX_ARRAY_SIZE)
4664	>	throw new OutOfMemoryError(oomeMsg);
4665	>	int m = (int)sz;
4666	>	T[] r = (a.length >= m) ? a :
4667	>	(T[])java.lang.reflect.Array
4668	>	.newInstance(a.getClass().getComponentType(), m);
4669	>	int n = r.length;
4670	>	int i = 0;
4671	>	for (E e : this) {
4672	>	if (i == n) {
4673	>	if (n >= MAX_ARRAY_SIZE)
4674	>	throw new OutOfMemoryError(oomeMsg);
4675	>	if (n >= MAX_ARRAY_SIZE - (MAX_ARRAY_SIZE >>> 1) - 1)
4676	>	n = MAX_ARRAY_SIZE;
4677	>	else
4678	>	n += (n >>> 1) + 1;
4679	>	r = Arrays.copyOf(r, n);
4680	>	}
4681	>	r[i++] = (T)e;
4682	>	}
4683	>	if (a == r && i < n) {
4684	>	r[i] = null; // null-terminate
4685	>	return r;
4686	>	}
4687	>	return (i == n) ? r : Arrays.copyOf(r, i);
4688	>	}
4689	>
4690	>	/**
4691	>	* Returns a string representation of this collection.
4692	>	* The string representation consists of the string representations
4693	>	* of the collection's elements in the order they are returned by
4694	>	* its iterator, enclosed in square brackets ({@code "[]"}).
4695	>	* Adjacent elements are separated by the characters {@code ", "}
4696	>	* (comma and space).  Elements are converted to strings as by
4697	>	* {@link String#valueOf(Object)}.
4698	>	*
4699	>	* @return a string representation of this collection
4700	>	*/
4701	>	public final String toString() {
4702	>	StringBuilder sb = new StringBuilder();
4703	>	sb.append('[');
4704	>	Iterator<E> it = iterator();
4705	>	if (it.hasNext()) {
4706	>	for (;;) {
4707	>	Object e = it.next();
4708	>	sb.append(e == this ? "(this Collection)" : e);
4709	>	if (!it.hasNext())
4710	>	break;
4711	>	sb.append(',').append(' ');
4712	>	}
4713	>	}
4714	>	return sb.append(']').toString();
4715	>	}
4716	>
4717	>	public final boolean containsAll(Collection<?> c) {
4718	>	if (c != this) {
4719	>	for (Object e : c) {
4720	>	if (e == null || !contains(e))
4721	>	return false;
4722	>	}
4723	>	}
4724	>	return true;
4725	>	}
4726	>
4727	>	public final boolean removeAll(Collection<?> c) {
4728	>	boolean modified = false;
4729	>	for (Iterator<E> it = iterator(); it.hasNext();) {
4730	>	if (c.contains(it.next())) {
4731	>	it.remove();
4732	>	modified = true;
4733	>	}
4734	>	}
4735	>	return modified;
4736		}
4737	<	public void clear() {
4738	<	ConcurrentHashMap.this.clear();
4737	>
4738	>	public final boolean retainAll(Collection<?> c) {
4739	>	boolean modified = false;
4740	>	for (Iterator<E> it = iterator(); it.hasNext();) {
4741	>	if (!c.contains(it.next())) {
4742	>	it.remove();
4743	>	modified = true;
4744	>	}
4745	>	}
4746	>	return modified;
4747		}
4748	<	public Object[] toArray() {
4749	<	Collection<Map.Entry<K,V>> c = new ArrayList<Map.Entry<K,V>>(size());
4750	<	for (Map.Entry<K,V> e : this)
4751	<	c.add(e);
4752	<	return c.toArray();
4753	<	}
4754	<	public <T> T[] toArray(T[] a) {
4755	<	Collection<Map.Entry<K,V>> c = new ArrayList<Map.Entry<K,V>>(size());
4756	<	for (Map.Entry<K,V> e : this)
4757	<	c.add(e);
4758	<	return c.toArray(a);
4748	>
4749	>	}
4750	>
4751	>	abstract static class CHMSetView<K,V,E>
4752	>	extends CHMCollectionView<K,V,E>
4753	>	implements Set<E>, java.io.Serializable {
4754	>	private static final long serialVersionUID = 7249069246763182397L;
4755	>	CHMSetView(ConcurrentHashMap<K,V> map) { super(map); }
4756	>
4757	>	// Implement Set API
4758	>
4759	>	/**
4760	>	* Implements {@link Set#hashCode()}.
4761	>	* @return the hash code value for this set
4762	>	*/
4763	>	public final int hashCode() {
4764	>	int h = 0;
4765	>	for (E e : this)
4766	>	h += e.hashCode();
4767	>	return h;
4768		}
4769
4770	+	/**
4771	+	* Implements {@link Set#equals(Object)}.
4772	+	* @param o object to be compared for equality with this set
4773	+	* @return {@code true} if the specified object is equal to this set
4774	+	*/
4775	+	public final boolean equals(Object o) {
4776	+	Set<?> c;
4777	+	return ((o instanceof Set) &&
4778	+	((c = (Set<?>)o) == this ||
4779	+	(containsAll(c) && c.containsAll(this))));
4780	+	}
4781		}
4782
4783	<	/* ---------------- Serialization Support -------------- */
4783	>	/**
4784	>	* A view of a ConcurrentHashMap as a {@link Set} of keys, in
4785	>	* which additions may optionally be enabled by mapping to a
4786	>	* common value.  This class cannot be directly instantiated.
4787	>	* See {@link #keySet() keySet()},
4788	>	* {@link #keySet(Object) keySet(V)},
4789	>	* {@link #newKeySet() newKeySet()},
4790	>	* {@link #newKeySet(int) newKeySet(int)}.
4791	>	*/
4792	>	public static class KeySetView<K,V>
4793	>	extends CHMSetView<K,V,K>
4794	>	implements Set<K>, java.io.Serializable {
4795	>	private static final long serialVersionUID = 7249069246763182397L;
4796	>	private final V value;
4797	>	KeySetView(ConcurrentHashMap<K,V> map, V value) {  // non-public
4798	>	super(map);
4799	>	this.value = value;
4800	>	}
4801	>
4802	>	/**
4803	>	* Returns the default mapped value for additions,
4804	>	* or {@code null} if additions are not supported.
4805	>	*
4806	>	* @return the default mapped value for additions, or {@code null}
4807	>	* if not supported
4808	>	*/
4809	>	public V getMappedValue() { return value; }
4810	>
4811	>	/**
4812	>	* {@inheritDoc}
4813	>	* @throws NullPointerException if the specified key is null
4814	>	*/
4815	>	public boolean contains(Object o) { return map.containsKey(o); }
4816	>
4817	>	/**
4818	>	* Removes the key from this map view, by removing the key (and its
4819	>	* corresponding value) from the backing map.  This method does
4820	>	* nothing if the key is not in the map.
4821	>	*
4822	>	* @param  o the key to be removed from the backing map
4823	>	* @return {@code true} if the backing map contained the specified key
4824	>	* @throws NullPointerException if the specified key is null
4825	>	*/
4826	>	public boolean remove(Object o) { return map.remove(o) != null; }
4827	>
4828	>	/**
4829	>	* @return an iterator over the keys of the backing map
4830	>	*/
4831	>	public Iterator<K> iterator() { return new KeyIterator<K,V>(map); }
4832	>
4833	>	/**
4834	>	* Adds the specified key to this set view by mapping the key to
4835	>	* the default mapped value in the backing map, if defined.
4836	>	*
4837	>	* @param e key to be added
4838	>	* @return {@code true} if this set changed as a result of the call
4839	>	* @throws NullPointerException if the specified key is null
4840	>	* @throws UnsupportedOperationException if no default mapped value
4841	>	* for additions was provided
4842	>	*/
4843	>	public boolean add(K e) {
4844	>	V v;
4845	>	if ((v = value) == null)
4846	>	throw new UnsupportedOperationException();
4847	>	return map.internalPut(e, v, true) == null;
4848	>	}
4849	>
4850	>	/**
4851	>	* Adds all of the elements in the specified collection to this set,
4852	>	* as if by calling {@link #add} on each one.
4853	>	*
4854	>	* @param c the elements to be inserted into this set
4855	>	* @return {@code true} if this set changed as a result of the call
4856	>	* @throws NullPointerException if the collection or any of its
4857	>	* elements are {@code null}
4858	>	* @throws UnsupportedOperationException if no default mapped value
4859	>	* for additions was provided
4860	>	*/
4861	>	public boolean addAll(Collection<? extends K> c) {
4862	>	boolean added = false;
4863	>	V v;
4864	>	if ((v = value) == null)
4865	>	throw new UnsupportedOperationException();
4866	>	for (K e : c) {
4867	>	if (map.internalPut(e, v, true) == null)
4868	>	added = true;
4869	>	}
4870	>	return added;
4871	>	}
4872	>
4873	>	public Spliterator<K> spliterator() {
4874	>	return new KeyIterator<>(map, null);
4875	>	}
4876	>
4877	>	}
4878
4879		/**
4880	<	* Save the state of the <tt>ConcurrentHashMap</tt> instance to a
4881	<	* stream (i.e., serialize it).
4882	<	* @param s the stream
4883	<	* @serialData
4884	<	* the key (Object) and value (Object)
4885	<	* for each key-value mapping, followed by a null pair.
4886	<	* The key-value mappings are emitted in no particular order.
4880	>	* A view of a ConcurrentHashMap as a {@link Collection} of
4881	>	* values, in which additions are disabled. This class cannot be
4882	>	* directly instantiated. See {@link #values()}.
4883	>	*
4884	>	* <p>The view's {@code iterator} is a "weakly consistent" iterator
4885	>	* that will never throw {@link ConcurrentModificationException},
4886	>	* and guarantees to traverse elements as they existed upon
4887	>	* construction of the iterator, and may (but is not guaranteed to)
4888	>	* reflect any modifications subsequent to construction.
4889		*/
4890	<	private void writeObject(java.io.ObjectOutputStream s) throws IOException  {
4891	<	s.defaultWriteObject();
4892	<
4893	<	for (int k = 0; k < segments.length; ++k) {
4894	<	Segment<K,V> seg = segments[k];
4895	<	seg.lock();
4896	<	try {
4897	<	HashEntry<K,V>[] tab = seg.table;
4898	<	for (int i = 0; i < tab.length; ++i) {
4899	<	for (HashEntry<K,V> e = tab[i]; e != null; e = e.next) {
4900	<	s.writeObject(e.key);
4901	<	s.writeObject(e.value);
4890	>	public static final class ValuesView<K,V>
4891	>	extends CHMCollectionView<K,V,V>
4892	>	implements Collection<V>, java.io.Serializable {
4893	>	private static final long serialVersionUID = 2249069246763182397L;
4894	>	ValuesView(ConcurrentHashMap<K,V> map) { super(map); }
4895	>	public final boolean contains(Object o) {
4896	>	return map.containsValue(o);
4897	>	}
4898	>	public final boolean remove(Object o) {
4899	>	if (o != null) {
4900	>	for (Iterator<V> it = iterator(); it.hasNext();) {
4901	>	if (o.equals(it.next())) {
4902	>	it.remove();
4903	>	return true;
4904		}
4905		}
1283	–	} finally {
1284	–	seg.unlock();
4906		}
4907	+	return false;
4908		}
4909	<	s.writeObject(null);
4910	<	s.writeObject(null);
4909	>
4910	>	/**
4911	>	* @return an iterator over the values of the backing map
4912	>	*/
4913	>	public final Iterator<V> iterator() {
4914	>	return new ValueIterator<K,V>(map);
4915	>	}
4916	>
4917	>	/** Always throws {@link UnsupportedOperationException}. */
4918	>	public final boolean add(V e) {
4919	>	throw new UnsupportedOperationException();
4920	>	}
4921	>	/** Always throws {@link UnsupportedOperationException}. */
4922	>	public final boolean addAll(Collection<? extends V> c) {
4923	>	throw new UnsupportedOperationException();
4924	>	}
4925	>
4926	>	public Spliterator<V> spliterator() {
4927	>	return new ValueIterator<K,V>(map, null);
4928	>	}
4929	>
4930		}
4931
4932		/**
4933	<	* Reconstitute the <tt>ConcurrentHashMap</tt> instance from a
4934	<	* stream (i.e., deserialize it).
4935	<	* @param s the stream
4933	>	* A view of a ConcurrentHashMap as a {@link Set} of (key, value)
4934	>	* entries.  This class cannot be directly instantiated. See
4935	>	* {@link #entrySet()}.
4936	>	*/
4937	>	public static final class EntrySetView<K,V>
4938	>	extends CHMSetView<K,V,Map.Entry<K,V>>
4939	>	implements Set<Map.Entry<K,V>>, java.io.Serializable {
4940	>	private static final long serialVersionUID = 2249069246763182397L;
4941	>	EntrySetView(ConcurrentHashMap<K,V> map) { super(map); }
4942	>
4943	>	public final boolean contains(Object o) {
4944	>	Object k, v, r; Map.Entry<?,?> e;
4945	>	return ((o instanceof Map.Entry) &&
4946	>	(k = (e = (Map.Entry<?,?>)o).getKey()) != null &&
4947	>	(r = map.get(k)) != null &&
4948	>	(v = e.getValue()) != null &&
4949	>	(v == r || v.equals(r)));
4950	>	}
4951	>	public final boolean remove(Object o) {
4952	>	Object k, v; Map.Entry<?,?> e;
4953	>	return ((o instanceof Map.Entry) &&
4954	>	(k = (e = (Map.Entry<?,?>)o).getKey()) != null &&
4955	>	(v = e.getValue()) != null &&
4956	>	map.remove(k, v));
4957	>	}
4958	>
4959	>	/**
4960	>	* @return an iterator over the entries of the backing map
4961	>	*/
4962	>	public final Iterator<Map.Entry<K,V>> iterator() {
4963	>	return new EntryIterator<K,V>(map);
4964	>	}
4965	>
4966	>	/**
4967	>	* Adds the specified mapping to this view.
4968	>	*
4969	>	* @param e mapping to be added
4970	>	* @return {@code true} if this set changed as a result of the call
4971	>	* @throws NullPointerException if the entry, its key, or its
4972	>	* value is null
4973	>	*/
4974	>	public final boolean add(Entry<K,V> e) {
4975	>	return map.internalPut(e.getKey(), e.getValue(), false) == null;
4976	>	}
4977	>	/**
4978	>	* Adds all of the mappings in the specified collection to this
4979	>	* set, as if by calling {@link #add(Map.Entry)} on each one.
4980	>	* @param c the mappings to be inserted into this set
4981	>	* @return {@code true} if this set changed as a result of the call
4982	>	* @throws NullPointerException if the collection or any of its
4983	>	* entries, keys, or values are null
4984	>	*/
4985	>	public final boolean addAll(Collection<? extends Entry<K,V>> c) {
4986	>	boolean added = false;
4987	>	for (Entry<K,V> e : c) {
4988	>	if (add(e))
4989	>	added = true;
4990	>	}
4991	>	return added;
4992	>	}
4993	>
4994	>	public Spliterator<Map.Entry<K,V>> spliterator() {
4995	>	return new EntryIterator<K,V>(map, null);
4996	>	}
4997	>
4998	>	}
4999	>
5000	>	// ---------------------------------------------------------------------
5001	>
5002	>	/**
5003	>	* Predefined tasks for performing bulk parallel operations on
5004	>	* ConcurrentHashMaps. These tasks follow the forms and rules used
5005	>	* for bulk operations. Each method has the same name, but returns
5006	>	* a task rather than invoking it. These methods may be useful in
5007	>	* custom applications such as submitting a task without waiting
5008	>	* for completion, using a custom pool, or combining with other
5009	>	* tasks.
5010		*/
5011	<	private void readObject(java.io.ObjectInputStream s)
5012	<	throws IOException, ClassNotFoundException  {
1298	<	s.defaultReadObject();
5011	>	public static class ForkJoinTasks {
5012	>	private ForkJoinTasks() {}
5013
5014	<	// Initialize each segment to be minimally sized, and let grow.
5015	<	for (int i = 0; i < segments.length; ++i) {
5016	<	segments[i].setTable(new HashEntry[1]);
5014	>	/**
5015	>	* Returns a task that when invoked, performs the given
5016	>	* action for each (key, value)
5017	>	*
5018	>	* @param map the map
5019	>	* @param action the action
5020	>	* @return the task
5021	>	*/
5022	>	public static <K,V> ForkJoinTask<Void> forEach
5023	>	(ConcurrentHashMap<K,V> map,
5024	>	BiConsumer<? super K, ? super V> action) {
5025	>	if (action == null) throw new NullPointerException();
5026	>	return new ForEachMappingTask<K,V>(map, null, -1, action);
5027		}
5028
5029	<	// Read the keys and values, and put the mappings in the table
5030	<	for (;;) {
5031	<	K key = (K) s.readObject();
5032	<	V value = (V) s.readObject();
5033	<	if (key == null)
5034	<	break;
5035	<	put(key, value);
5029	>	/**
5030	>	* Returns a task that when invoked, performs the given
5031	>	* action for each non-null transformation of each (key, value)
5032	>	*
5033	>	* @param map the map
5034	>	* @param transformer a function returning the transformation
5035	>	* for an element, or null if there is no transformation (in
5036	>	* which case the action is not applied)
5037	>	* @param action the action
5038	>	* @return the task
5039	>	*/
5040	>	public static <K,V,U> ForkJoinTask<Void> forEach
5041	>	(ConcurrentHashMap<K,V> map,
5042	>	BiFunction<? super K, ? super V, ? extends U> transformer,
5043	>	Consumer<? super U> action) {
5044	>	if (transformer == null || action == null)
5045	>	throw new NullPointerException();
5046	>	return new ForEachTransformedMappingTask<K,V,U>
5047	>	(map, null, -1, transformer, action);
5048	>	}
5049	>
5050	>	/**
5051	>	* Returns a task that when invoked, returns a non-null result
5052	>	* from applying the given search function on each (key,
5053	>	* value), or null if none. Upon success, further element
5054	>	* processing is suppressed and the results of any other
5055	>	* parallel invocations of the search function are ignored.
5056	>	*
5057	>	* @param map the map
5058	>	* @param searchFunction a function returning a non-null
5059	>	* result on success, else null
5060	>	* @return the task
5061	>	*/
5062	>	public static <K,V,U> ForkJoinTask<U> search
5063	>	(ConcurrentHashMap<K,V> map,
5064	>	BiFunction<? super K, ? super V, ? extends U> searchFunction) {
5065	>	if (searchFunction == null) throw new NullPointerException();
5066	>	return new SearchMappingsTask<K,V,U>
5067	>	(map, null, -1, searchFunction,
5068	>	new AtomicReference<U>());
5069	>	}
5070	>
5071	>	/**
5072	>	* Returns a task that when invoked, returns the result of
5073	>	* accumulating the given transformation of all (key, value) pairs
5074	>	* using the given reducer to combine values, or null if none.
5075	>	*
5076	>	* @param map the map
5077	>	* @param transformer a function returning the transformation
5078	>	* for an element, or null if there is no transformation (in
5079	>	* which case it is not combined)
5080	>	* @param reducer a commutative associative combining function
5081	>	* @return the task
5082	>	*/
5083	>	public static <K,V,U> ForkJoinTask<U> reduce
5084	>	(ConcurrentHashMap<K,V> map,
5085	>	BiFunction<? super K, ? super V, ? extends U> transformer,
5086	>	BiFunction<? super U, ? super U, ? extends U> reducer) {
5087	>	if (transformer == null || reducer == null)
5088	>	throw new NullPointerException();
5089	>	return new MapReduceMappingsTask<K,V,U>
5090	>	(map, null, -1, null, transformer, reducer);
5091	>	}
5092	>
5093	>	/**
5094	>	* Returns a task that when invoked, returns the result of
5095	>	* accumulating the given transformation of all (key, value) pairs
5096	>	* using the given reducer to combine values, and the given
5097	>	* basis as an identity value.
5098	>	*
5099	>	* @param map the map
5100	>	* @param transformer a function returning the transformation
5101	>	* for an element
5102	>	* @param basis the identity (initial default value) for the reduction
5103	>	* @param reducer a commutative associative combining function
5104	>	* @return the task
5105	>	*/
5106	>	public static <K,V> ForkJoinTask<Double> reduceToDouble
5107	>	(ConcurrentHashMap<K,V> map,
5108	>	ToDoubleBiFunction<? super K, ? super V> transformer,
5109	>	double basis,
5110	>	DoubleBinaryOperator reducer) {
5111	>	if (transformer == null || reducer == null)
5112	>	throw new NullPointerException();
5113	>	return new MapReduceMappingsToDoubleTask<K,V>
5114	>	(map, null, -1, null, transformer, basis, reducer);
5115	>	}
5116	>
5117	>	/**
5118	>	* Returns a task that when invoked, returns the result of
5119	>	* accumulating the given transformation of all (key, value) pairs
5120	>	* using the given reducer to combine values, and the given
5121	>	* basis as an identity value.
5122	>	*
5123	>	* @param map the map
5124	>	* @param transformer a function returning the transformation
5125	>	* for an element
5126	>	* @param basis the identity (initial default value) for the reduction
5127	>	* @param reducer a commutative associative combining function
5128	>	* @return the task
5129	>	*/
5130	>	public static <K,V> ForkJoinTask<Long> reduceToLong
5131	>	(ConcurrentHashMap<K,V> map,
5132	>	ToLongBiFunction<? super K, ? super V> transformer,
5133	>	long basis,
5134	>	LongBinaryOperator reducer) {
5135	>	if (transformer == null || reducer == null)
5136	>	throw new NullPointerException();
5137	>	return new MapReduceMappingsToLongTask<K,V>
5138	>	(map, null, -1, null, transformer, basis, reducer);
5139	>	}
5140	>
5141	>	/**
5142	>	* Returns a task that when invoked, returns the result of
5143	>	* accumulating the given transformation of all (key, value) pairs
5144	>	* using the given reducer to combine values, and the given
5145	>	* basis as an identity value.
5146	>	*
5147	>	* @param map the map
5148	>	* @param transformer a function returning the transformation
5149	>	* for an element
5150	>	* @param basis the identity (initial default value) for the reduction
5151	>	* @param reducer a commutative associative combining function
5152	>	* @return the task
5153	>	*/
5154	>	public static <K,V> ForkJoinTask<Integer> reduceToInt
5155	>	(ConcurrentHashMap<K,V> map,
5156	>	ToIntBiFunction<? super K, ? super V> transformer,
5157	>	int basis,
5158	>	IntBinaryOperator reducer) {
5159	>	if (transformer == null || reducer == null)
5160	>	throw new NullPointerException();
5161	>	return new MapReduceMappingsToIntTask<K,V>
5162	>	(map, null, -1, null, transformer, basis, reducer);
5163	>	}
5164	>
5165	>	/**
5166	>	* Returns a task that when invoked, performs the given action
5167	>	* for each key.
5168	>	*
5169	>	* @param map the map
5170	>	* @param action the action
5171	>	* @return the task
5172	>	*/
5173	>	public static <K,V> ForkJoinTask<Void> forEachKey
5174	>	(ConcurrentHashMap<K,V> map,
5175	>	Consumer<? super K> action) {
5176	>	if (action == null) throw new NullPointerException();
5177	>	return new ForEachKeyTask<K,V>(map, null, -1, action);
5178	>	}
5179	>
5180	>	/**
5181	>	* Returns a task that when invoked, performs the given action
5182	>	* for each non-null transformation of each key.
5183	>	*
5184	>	* @param map the map
5185	>	* @param transformer a function returning the transformation
5186	>	* for an element, or null if there is no transformation (in
5187	>	* which case the action is not applied)
5188	>	* @param action the action
5189	>	* @return the task
5190	>	*/
5191	>	public static <K,V,U> ForkJoinTask<Void> forEachKey
5192	>	(ConcurrentHashMap<K,V> map,
5193	>	Function<? super K, ? extends U> transformer,
5194	>	Consumer<? super U> action) {
5195	>	if (transformer == null || action == null)
5196	>	throw new NullPointerException();
5197	>	return new ForEachTransformedKeyTask<K,V,U>
5198	>	(map, null, -1, transformer, action);
5199	>	}
5200	>
5201	>	/**
5202	>	* Returns a task that when invoked, returns a non-null result
5203	>	* from applying the given search function on each key, or
5204	>	* null if none.  Upon success, further element processing is
5205	>	* suppressed and the results of any other parallel
5206	>	* invocations of the search function are ignored.
5207	>	*
5208	>	* @param map the map
5209	>	* @param searchFunction a function returning a non-null
5210	>	* result on success, else null
5211	>	* @return the task
5212	>	*/
5213	>	public static <K,V,U> ForkJoinTask<U> searchKeys
5214	>	(ConcurrentHashMap<K,V> map,
5215	>	Function<? super K, ? extends U> searchFunction) {
5216	>	if (searchFunction == null) throw new NullPointerException();
5217	>	return new SearchKeysTask<K,V,U>
5218	>	(map, null, -1, searchFunction,
5219	>	new AtomicReference<U>());
5220	>	}
5221	>
5222	>	/**
5223	>	* Returns a task that when invoked, returns the result of
5224	>	* accumulating all keys using the given reducer to combine
5225	>	* values, or null if none.
5226	>	*
5227	>	* @param map the map
5228	>	* @param reducer a commutative associative combining function
5229	>	* @return the task
5230	>	*/
5231	>	public static <K,V> ForkJoinTask<K> reduceKeys
5232	>	(ConcurrentHashMap<K,V> map,
5233	>	BiFunction<? super K, ? super K, ? extends K> reducer) {
5234	>	if (reducer == null) throw new NullPointerException();
5235	>	return new ReduceKeysTask<K,V>
5236	>	(map, null, -1, null, reducer);
5237	>	}
5238	>
5239	>	/**
5240	>	* Returns a task that when invoked, returns the result of
5241	>	* accumulating the given transformation of all keys using the given
5242	>	* reducer to combine values, or null if none.
5243	>	*
5244	>	* @param map the map
5245	>	* @param transformer a function returning the transformation
5246	>	* for an element, or null if there is no transformation (in
5247	>	* which case it is not combined)
5248	>	* @param reducer a commutative associative combining function
5249	>	* @return the task
5250	>	*/
5251	>	public static <K,V,U> ForkJoinTask<U> reduceKeys
5252	>	(ConcurrentHashMap<K,V> map,
5253	>	Function<? super K, ? extends U> transformer,
5254	>	BiFunction<? super U, ? super U, ? extends U> reducer) {
5255	>	if (transformer == null || reducer == null)
5256	>	throw new NullPointerException();
5257	>	return new MapReduceKeysTask<K,V,U>
5258	>	(map, null, -1, null, transformer, reducer);
5259	>	}
5260	>
5261	>	/**
5262	>	* Returns a task that when invoked, returns the result of
5263	>	* accumulating the given transformation of all keys using the given
5264	>	* reducer to combine values, and the given basis as an
5265	>	* identity value.
5266	>	*
5267	>	* @param map the map
5268	>	* @param transformer a function returning the transformation
5269	>	* for an element
5270	>	* @param basis the identity (initial default value) for the reduction
5271	>	* @param reducer a commutative associative combining function
5272	>	* @return the task
5273	>	*/
5274	>	public static <K,V> ForkJoinTask<Double> reduceKeysToDouble
5275	>	(ConcurrentHashMap<K,V> map,
5276	>	ToDoubleFunction<? super K> transformer,
5277	>	double basis,
5278	>	DoubleBinaryOperator reducer) {
5279	>	if (transformer == null || reducer == null)
5280	>	throw new NullPointerException();
5281	>	return new MapReduceKeysToDoubleTask<K,V>
5282	>	(map, null, -1, null, transformer, basis, reducer);
5283	>	}
5284	>
5285	>	/**
5286	>	* Returns a task that when invoked, returns the result of
5287	>	* accumulating the given transformation of all keys using the given
5288	>	* reducer to combine values, and the given basis as an
5289	>	* identity value.
5290	>	*
5291	>	* @param map the map
5292	>	* @param transformer a function returning the transformation
5293	>	* for an element
5294	>	* @param basis the identity (initial default value) for the reduction
5295	>	* @param reducer a commutative associative combining function
5296	>	* @return the task
5297	>	*/
5298	>	public static <K,V> ForkJoinTask<Long> reduceKeysToLong
5299	>	(ConcurrentHashMap<K,V> map,
5300	>	ToLongFunction<? super K> transformer,
5301	>	long basis,
5302	>	LongBinaryOperator reducer) {
5303	>	if (transformer == null || reducer == null)
5304	>	throw new NullPointerException();
5305	>	return new MapReduceKeysToLongTask<K,V>
5306	>	(map, null, -1, null, transformer, basis, reducer);
5307	>	}
5308	>
5309	>	/**
5310	>	* Returns a task that when invoked, returns the result of
5311	>	* accumulating the given transformation of all keys using the given
5312	>	* reducer to combine values, and the given basis as an
5313	>	* identity value.
5314	>	*
5315	>	* @param map the map
5316	>	* @param transformer a function returning the transformation
5317	>	* for an element
5318	>	* @param basis the identity (initial default value) for the reduction
5319	>	* @param reducer a commutative associative combining function
5320	>	* @return the task
5321	>	*/
5322	>	public static <K,V> ForkJoinTask<Integer> reduceKeysToInt
5323	>	(ConcurrentHashMap<K,V> map,
5324	>	ToIntFunction<? super K> transformer,
5325	>	int basis,
5326	>	IntBinaryOperator reducer) {
5327	>	if (transformer == null || reducer == null)
5328	>	throw new NullPointerException();
5329	>	return new MapReduceKeysToIntTask<K,V>
5330	>	(map, null, -1, null, transformer, basis, reducer);
5331	>	}
5332	>
5333	>	/**
5334	>	* Returns a task that when invoked, performs the given action
5335	>	* for each value.
5336	>	*
5337	>	* @param map the map
5338	>	* @param action the action
5339	>	* @return the task
5340	>	*/
5341	>	public static <K,V> ForkJoinTask<Void> forEachValue
5342	>	(ConcurrentHashMap<K,V> map,
5343	>	Consumer<? super V> action) {
5344	>	if (action == null) throw new NullPointerException();
5345	>	return new ForEachValueTask<K,V>(map, null, -1, action);
5346	>	}
5347	>
5348	>	/**
5349	>	* Returns a task that when invoked, performs the given action
5350	>	* for each non-null transformation of each value.
5351	>	*
5352	>	* @param map the map
5353	>	* @param transformer a function returning the transformation
5354	>	* for an element, or null if there is no transformation (in
5355	>	* which case the action is not applied)
5356	>	* @param action the action
5357	>	* @return the task
5358	>	*/
5359	>	public static <K,V,U> ForkJoinTask<Void> forEachValue
5360	>	(ConcurrentHashMap<K,V> map,
5361	>	Function<? super V, ? extends U> transformer,
5362	>	Consumer<? super U> action) {
5363	>	if (transformer == null || action == null)
5364	>	throw new NullPointerException();
5365	>	return new ForEachTransformedValueTask<K,V,U>
5366	>	(map, null, -1, transformer, action);
5367	>	}
5368	>
5369	>	/**
5370	>	* Returns a task that when invoked, returns a non-null result
5371	>	* from applying the given search function on each value, or
5372	>	* null if none.  Upon success, further element processing is
5373	>	* suppressed and the results of any other parallel
5374	>	* invocations of the search function are ignored.
5375	>	*
5376	>	* @param map the map
5377	>	* @param searchFunction a function returning a non-null
5378	>	* result on success, else null
5379	>	* @return the task
5380	>	*/
5381	>	public static <K,V,U> ForkJoinTask<U> searchValues
5382	>	(ConcurrentHashMap<K,V> map,
5383	>	Function<? super V, ? extends U> searchFunction) {
5384	>	if (searchFunction == null) throw new NullPointerException();
5385	>	return new SearchValuesTask<K,V,U>
5386	>	(map, null, -1, searchFunction,
5387	>	new AtomicReference<U>());
5388	>	}
5389	>
5390	>	/**
5391	>	* Returns a task that when invoked, returns the result of
5392	>	* accumulating all values using the given reducer to combine
5393	>	* values, or null if none.
5394	>	*
5395	>	* @param map the map
5396	>	* @param reducer a commutative associative combining function
5397	>	* @return the task
5398	>	*/
5399	>	public static <K,V> ForkJoinTask<V> reduceValues
5400	>	(ConcurrentHashMap<K,V> map,
5401	>	BiFunction<? super V, ? super V, ? extends V> reducer) {
5402	>	if (reducer == null) throw new NullPointerException();
5403	>	return new ReduceValuesTask<K,V>
5404	>	(map, null, -1, null, reducer);
5405	>	}
5406	>
5407	>	/**
5408	>	* Returns a task that when invoked, returns the result of
5409	>	* accumulating the given transformation of all values using the
5410	>	* given reducer to combine values, or null if none.
5411	>	*
5412	>	* @param map the map
5413	>	* @param transformer a function returning the transformation
5414	>	* for an element, or null if there is no transformation (in
5415	>	* which case it is not combined)
5416	>	* @param reducer a commutative associative combining function
5417	>	* @return the task
5418	>	*/
5419	>	public static <K,V,U> ForkJoinTask<U> reduceValues
5420	>	(ConcurrentHashMap<K,V> map,
5421	>	Function<? super V, ? extends U> transformer,
5422	>	BiFunction<? super U, ? super U, ? extends U> reducer) {
5423	>	if (transformer == null || reducer == null)
5424	>	throw new NullPointerException();
5425	>	return new MapReduceValuesTask<K,V,U>
5426	>	(map, null, -1, null, transformer, reducer);
5427	>	}
5428	>
5429	>	/**
5430	>	* Returns a task that when invoked, returns the result of
5431	>	* accumulating the given transformation of all values using the
5432	>	* given reducer to combine values, and the given basis as an
5433	>	* identity value.
5434	>	*
5435	>	* @param map the map
5436	>	* @param transformer a function returning the transformation
5437	>	* for an element
5438	>	* @param basis the identity (initial default value) for the reduction
5439	>	* @param reducer a commutative associative combining function
5440	>	* @return the task
5441	>	*/
5442	>	public static <K,V> ForkJoinTask<Double> reduceValuesToDouble
5443	>	(ConcurrentHashMap<K,V> map,
5444	>	ToDoubleFunction<? super V> transformer,
5445	>	double basis,
5446	>	DoubleBinaryOperator reducer) {
5447	>	if (transformer == null || reducer == null)
5448	>	throw new NullPointerException();
5449	>	return new MapReduceValuesToDoubleTask<K,V>
5450	>	(map, null, -1, null, transformer, basis, reducer);
5451	>	}
5452	>
5453	>	/**
5454	>	* Returns a task that when invoked, returns the result of
5455	>	* accumulating the given transformation of all values using the
5456	>	* given reducer to combine values, and the given basis as an
5457	>	* identity value.
5458	>	*
5459	>	* @param map the map
5460	>	* @param transformer a function returning the transformation
5461	>	* for an element
5462	>	* @param basis the identity (initial default value) for the reduction
5463	>	* @param reducer a commutative associative combining function
5464	>	* @return the task
5465	>	*/
5466	>	public static <K,V> ForkJoinTask<Long> reduceValuesToLong
5467	>	(ConcurrentHashMap<K,V> map,
5468	>	ToLongFunction<? super V> transformer,
5469	>	long basis,
5470	>	LongBinaryOperator reducer) {
5471	>	if (transformer == null || reducer == null)
5472	>	throw new NullPointerException();
5473	>	return new MapReduceValuesToLongTask<K,V>
5474	>	(map, null, -1, null, transformer, basis, reducer);
5475	>	}
5476	>
5477	>	/**
5478	>	* Returns a task that when invoked, returns the result of
5479	>	* accumulating the given transformation of all values using the
5480	>	* given reducer to combine values, and the given basis as an
5481	>	* identity value.
5482	>	*
5483	>	* @param map the map
5484	>	* @param transformer a function returning the transformation
5485	>	* for an element
5486	>	* @param basis the identity (initial default value) for the reduction
5487	>	* @param reducer a commutative associative combining function
5488	>	* @return the task
5489	>	*/
5490	>	public static <K,V> ForkJoinTask<Integer> reduceValuesToInt
5491	>	(ConcurrentHashMap<K,V> map,
5492	>	ToIntFunction<? super V> transformer,
5493	>	int basis,
5494	>	IntBinaryOperator reducer) {
5495	>	if (transformer == null || reducer == null)
5496	>	throw new NullPointerException();
5497	>	return new MapReduceValuesToIntTask<K,V>
5498	>	(map, null, -1, null, transformer, basis, reducer);
5499	>	}
5500	>
5501	>	/**
5502	>	* Returns a task that when invoked, perform the given action
5503	>	* for each entry.
5504	>	*
5505	>	* @param map the map
5506	>	* @param action the action
5507	>	* @return the task
5508	>	*/
5509	>	public static <K,V> ForkJoinTask<Void> forEachEntry
5510	>	(ConcurrentHashMap<K,V> map,
5511	>	Consumer<? super Map.Entry<K,V>> action) {
5512	>	if (action == null) throw new NullPointerException();
5513	>	return new ForEachEntryTask<K,V>(map, null, -1, action);
5514	>	}
5515	>
5516	>	/**
5517	>	* Returns a task that when invoked, perform the given action
5518	>	* for each non-null transformation of each entry.
5519	>	*
5520	>	* @param map the map
5521	>	* @param transformer a function returning the transformation
5522	>	* for an element, or null if there is no transformation (in
5523	>	* which case the action is not applied)
5524	>	* @param action the action
5525	>	* @return the task
5526	>	*/
5527	>	public static <K,V,U> ForkJoinTask<Void> forEachEntry
5528	>	(ConcurrentHashMap<K,V> map,
5529	>	Function<Map.Entry<K,V>, ? extends U> transformer,
5530	>	Consumer<? super U> action) {
5531	>	if (transformer == null || action == null)
5532	>	throw new NullPointerException();
5533	>	return new ForEachTransformedEntryTask<K,V,U>
5534	>	(map, null, -1, transformer, action);
5535	>	}
5536	>
5537	>	/**
5538	>	* Returns a task that when invoked, returns a non-null result
5539	>	* from applying the given search function on each entry, or
5540	>	* null if none.  Upon success, further element processing is
5541	>	* suppressed and the results of any other parallel
5542	>	* invocations of the search function are ignored.
5543	>	*
5544	>	* @param map the map
5545	>	* @param searchFunction a function returning a non-null
5546	>	* result on success, else null
5547	>	* @return the task
5548	>	*/
5549	>	public static <K,V,U> ForkJoinTask<U> searchEntries
5550	>	(ConcurrentHashMap<K,V> map,
5551	>	Function<Map.Entry<K,V>, ? extends U> searchFunction) {
5552	>	if (searchFunction == null) throw new NullPointerException();
5553	>	return new SearchEntriesTask<K,V,U>
5554	>	(map, null, -1, searchFunction,
5555	>	new AtomicReference<U>());
5556	>	}
5557	>
5558	>	/**
5559	>	* Returns a task that when invoked, returns the result of
5560	>	* accumulating all entries using the given reducer to combine
5561	>	* values, or null if none.
5562	>	*
5563	>	* @param map the map
5564	>	* @param reducer a commutative associative combining function
5565	>	* @return the task
5566	>	*/
5567	>	public static <K,V> ForkJoinTask<Map.Entry<K,V>> reduceEntries
5568	>	(ConcurrentHashMap<K,V> map,
5569	>	BiFunction<Map.Entry<K,V>, Map.Entry<K,V>, ? extends Map.Entry<K,V>> reducer) {
5570	>	if (reducer == null) throw new NullPointerException();
5571	>	return new ReduceEntriesTask<K,V>
5572	>	(map, null, -1, null, reducer);
5573	>	}
5574	>
5575	>	/**
5576	>	* Returns a task that when invoked, returns the result of
5577	>	* accumulating the given transformation of all entries using the
5578	>	* given reducer to combine values, or null if none.
5579	>	*
5580	>	* @param map the map
5581	>	* @param transformer a function returning the transformation
5582	>	* for an element, or null if there is no transformation (in
5583	>	* which case it is not combined)
5584	>	* @param reducer a commutative associative combining function
5585	>	* @return the task
5586	>	*/
5587	>	public static <K,V,U> ForkJoinTask<U> reduceEntries
5588	>	(ConcurrentHashMap<K,V> map,
5589	>	Function<Map.Entry<K,V>, ? extends U> transformer,
5590	>	BiFunction<? super U, ? super U, ? extends U> reducer) {
5591	>	if (transformer == null || reducer == null)
5592	>	throw new NullPointerException();
5593	>	return new MapReduceEntriesTask<K,V,U>
5594	>	(map, null, -1, null, transformer, reducer);
5595	>	}
5596	>
5597	>	/**
5598	>	* Returns a task that when invoked, returns the result of
5599	>	* accumulating the given transformation of all entries using the
5600	>	* given reducer to combine values, and the given basis as an
5601	>	* identity value.
5602	>	*
5603	>	* @param map the map
5604	>	* @param transformer a function returning the transformation
5605	>	* for an element
5606	>	* @param basis the identity (initial default value) for the reduction
5607	>	* @param reducer a commutative associative combining function
5608	>	* @return the task
5609	>	*/
5610	>	public static <K,V> ForkJoinTask<Double> reduceEntriesToDouble
5611	>	(ConcurrentHashMap<K,V> map,
5612	>	ToDoubleFunction<Map.Entry<K,V>> transformer,
5613	>	double basis,
5614	>	DoubleBinaryOperator reducer) {
5615	>	if (transformer == null || reducer == null)
5616	>	throw new NullPointerException();
5617	>	return new MapReduceEntriesToDoubleTask<K,V>
5618	>	(map, null, -1, null, transformer, basis, reducer);
5619	>	}
5620	>
5621	>	/**
5622	>	* Returns a task that when invoked, returns the result of
5623	>	* accumulating the given transformation of all entries using the
5624	>	* given reducer to combine values, and the given basis as an
5625	>	* identity value.
5626	>	*
5627	>	* @param map the map
5628	>	* @param transformer a function returning the transformation
5629	>	* for an element
5630	>	* @param basis the identity (initial default value) for the reduction
5631	>	* @param reducer a commutative associative combining function
5632	>	* @return the task
5633	>	*/
5634	>	public static <K,V> ForkJoinTask<Long> reduceEntriesToLong
5635	>	(ConcurrentHashMap<K,V> map,
5636	>	ToLongFunction<Map.Entry<K,V>> transformer,
5637	>	long basis,
5638	>	LongBinaryOperator reducer) {
5639	>	if (transformer == null || reducer == null)
5640	>	throw new NullPointerException();
5641	>	return new MapReduceEntriesToLongTask<K,V>
5642	>	(map, null, -1, null, transformer, basis, reducer);
5643	>	}
5644	>
5645	>	/**
5646	>	* Returns a task that when invoked, returns the result of
5647	>	* accumulating the given transformation of all entries using the
5648	>	* given reducer to combine values, and the given basis as an
5649	>	* identity value.
5650	>	*
5651	>	* @param map the map
5652	>	* @param transformer a function returning the transformation
5653	>	* for an element
5654	>	* @param basis the identity (initial default value) for the reduction
5655	>	* @param reducer a commutative associative combining function
5656	>	* @return the task
5657	>	*/
5658	>	public static <K,V> ForkJoinTask<Integer> reduceEntriesToInt
5659	>	(ConcurrentHashMap<K,V> map,
5660	>	ToIntFunction<Map.Entry<K,V>> transformer,
5661	>	int basis,
5662	>	IntBinaryOperator reducer) {
5663	>	if (transformer == null || reducer == null)
5664	>	throw new NullPointerException();
5665	>	return new MapReduceEntriesToIntTask<K,V>
5666	>	(map, null, -1, null, transformer, basis, reducer);
5667	>	}
5668	>	}
5669	>
5670	>	// -------------------------------------------------------
5671	>
5672	>	/*
5673	>	* Task classes. Coded in a regular but ugly format/style to
5674	>	* simplify checks that each variant differs in the right way from
5675	>	* others. The null screenings exist because compilers cannot tell
5676	>	* that we've already null-checked task arguments, so we force
5677	>	* simplest hoisted bypass to help avoid convoluted traps.
5678	>	*/
5679	>
5680	>	@SuppressWarnings("serial") static final class ForEachKeyTask<K,V>
5681	>	extends Traverser<K,V,Void> {
5682	>	final Consumer<? super K> action;
5683	>	ForEachKeyTask
5684	>	(ConcurrentHashMap<K,V> m, Traverser<K,V,?> p, int b,
5685	>	Consumer<? super K> action) {
5686	>	super(m, p, b);
5687	>	this.action = action;
5688	>	}
5689	>	public final void compute() {
5690	>	final Consumer<? super K> action;
5691	>	if ((action = this.action) != null) {
5692	>	for (int b; (b = preSplit()) > 0;)
5693	>	new ForEachKeyTask<K,V>(map, this, b, action).fork();
5694	>	forEachKey(action);
5695	>	propagateCompletion();
5696	>	}
5697	>	}
5698	>	}
5699	>
5700	>	@SuppressWarnings("serial") static final class ForEachValueTask<K,V>
5701	>	extends Traverser<K,V,Void> {
5702	>	final Consumer<? super V> action;
5703	>	ForEachValueTask
5704	>	(ConcurrentHashMap<K,V> m, Traverser<K,V,?> p, int b,
5705	>	Consumer<? super V> action) {
5706	>	super(m, p, b);
5707	>	this.action = action;
5708	>	}
5709	>	public final void compute() {
5710	>	final Consumer<? super V> action;
5711	>	if ((action = this.action) != null) {
5712	>	for (int b; (b = preSplit()) > 0;)
5713	>	new ForEachValueTask<K,V>(map, this, b, action).fork();
5714	>	forEachValue(action);
5715	>	propagateCompletion();
5716	>	}
5717	>	}
5718	>	}
5719	>
5720	>	@SuppressWarnings("serial") static final class ForEachEntryTask<K,V>
5721	>	extends Traverser<K,V,Void> {
5722	>	final Consumer<? super Entry<K,V>> action;
5723	>	ForEachEntryTask
5724	>	(ConcurrentHashMap<K,V> m, Traverser<K,V,?> p, int b,
5725	>	Consumer<? super Entry<K,V>> action) {
5726	>	super(m, p, b);
5727	>	this.action = action;
5728	>	}
5729	>	public final void compute() {
5730	>	final Consumer<? super Entry<K,V>> action;
5731	>	if ((action = this.action) != null) {
5732	>	for (int b; (b = preSplit()) > 0;)
5733	>	new ForEachEntryTask<K,V>(map, this, b, action).fork();
5734	>	V v;
5735	>	while ((v = advanceValue()) != null)
5736	>	action.accept(entryFor(nextKey, v));
5737	>	propagateCompletion();
5738	>	}
5739	>	}
5740	>	}
5741	>
5742	>	@SuppressWarnings("serial") static final class ForEachMappingTask<K,V>
5743	>	extends Traverser<K,V,Void> {
5744	>	final BiConsumer<? super K, ? super V> action;
5745	>	ForEachMappingTask
5746	>	(ConcurrentHashMap<K,V> m, Traverser<K,V,?> p, int b,
5747	>	BiConsumer<? super K,? super V> action) {
5748	>	super(m, p, b);
5749	>	this.action = action;
5750	>	}
5751	>	public final void compute() {
5752	>	final BiConsumer<? super K, ? super V> action;
5753	>	if ((action = this.action) != null) {
5754	>	for (int b; (b = preSplit()) > 0;)
5755	>	new ForEachMappingTask<K,V>(map, this, b, action).fork();
5756	>	V v;
5757	>	while ((v = advanceValue()) != null)
5758	>	action.accept(nextKey, v);
5759	>	propagateCompletion();
5760	>	}
5761	>	}
5762	>	}
5763	>
5764	>	@SuppressWarnings("serial") static final class ForEachTransformedKeyTask<K,V,U>
5765	>	extends Traverser<K,V,Void> {
5766	>	final Function<? super K, ? extends U> transformer;
5767	>	final Consumer<? super U> action;
5768	>	ForEachTransformedKeyTask
5769	>	(ConcurrentHashMap<K,V> m, Traverser<K,V,?> p, int b,
5770	>	Function<? super K, ? extends U> transformer, Consumer<? super U> action) {
5771	>	super(m, p, b);
5772	>	this.transformer = transformer; this.action = action;
5773	>	}
5774	>	public final void compute() {
5775	>	final Function<? super K, ? extends U> transformer;
5776	>	final Consumer<? super U> action;
5777	>	if ((transformer = this.transformer) != null &&
5778	>	(action = this.action) != null) {
5779	>	for (int b; (b = preSplit()) > 0;)
5780	>	new ForEachTransformedKeyTask<K,V,U>
5781	>	(map, this, b, transformer, action).fork();
5782	>	K k; U u;
5783	>	while ((k = advanceKey()) != null) {
5784	>	if ((u = transformer.apply(k)) != null)
5785	>	action.accept(u);
5786	>	}
5787	>	propagateCompletion();
5788	>	}
5789		}
5790		}
5791	+
5792	+	@SuppressWarnings("serial") static final class ForEachTransformedValueTask<K,V,U>
5793	+	extends Traverser<K,V,Void> {
5794	+	final Function<? super V, ? extends U> transformer;
5795	+	final Consumer<? super U> action;
5796	+	ForEachTransformedValueTask
5797	+	(ConcurrentHashMap<K,V> m, Traverser<K,V,?> p, int b,
5798	+	Function<? super V, ? extends U> transformer, Consumer<? super U> action) {
5799	+	super(m, p, b);
5800	+	this.transformer = transformer; this.action = action;
5801	+	}
5802	+	public final void compute() {
5803	+	final Function<? super V, ? extends U> transformer;
5804	+	final Consumer<? super U> action;
5805	+	if ((transformer = this.transformer) != null &&
5806	+	(action = this.action) != null) {
5807	+	for (int b; (b = preSplit()) > 0;)
5808	+	new ForEachTransformedValueTask<K,V,U>
5809	+	(map, this, b, transformer, action).fork();
5810	+	V v; U u;
5811	+	while ((v = advanceValue()) != null) {
5812	+	if ((u = transformer.apply(v)) != null)
5813	+	action.accept(u);
5814	+	}
5815	+	propagateCompletion();
5816	+	}
5817	+	}
5818	+	}
5819	+
5820	+	@SuppressWarnings("serial") static final class ForEachTransformedEntryTask<K,V,U>
5821	+	extends Traverser<K,V,Void> {
5822	+	final Function<Map.Entry<K,V>, ? extends U> transformer;
5823	+	final Consumer<? super U> action;
5824	+	ForEachTransformedEntryTask
5825	+	(ConcurrentHashMap<K,V> m, Traverser<K,V,?> p, int b,
5826	+	Function<Map.Entry<K,V>, ? extends U> transformer, Consumer<? super U> action) {
5827	+	super(m, p, b);
5828	+	this.transformer = transformer; this.action = action;
5829	+	}
5830	+	public final void compute() {
5831	+	final Function<Map.Entry<K,V>, ? extends U> transformer;
5832	+	final Consumer<? super U> action;
5833	+	if ((transformer = this.transformer) != null &&
5834	+	(action = this.action) != null) {
5835	+	for (int b; (b = preSplit()) > 0;)
5836	+	new ForEachTransformedEntryTask<K,V,U>
5837	+	(map, this, b, transformer, action).fork();
5838	+	V v; U u;
5839	+	while ((v = advanceValue()) != null) {
5840	+	if ((u = transformer.apply(entryFor(nextKey,
5841	+	v))) != null)
5842	+	action.accept(u);
5843	+	}
5844	+	propagateCompletion();
5845	+	}
5846	+	}
5847	+	}
5848	+
5849	+	@SuppressWarnings("serial") static final class ForEachTransformedMappingTask<K,V,U>
5850	+	extends Traverser<K,V,Void> {
5851	+	final BiFunction<? super K, ? super V, ? extends U> transformer;
5852	+	final Consumer<? super U> action;
5853	+	ForEachTransformedMappingTask
5854	+	(ConcurrentHashMap<K,V> m, Traverser<K,V,?> p, int b,
5855	+	BiFunction<? super K, ? super V, ? extends U> transformer,
5856	+	Consumer<? super U> action) {
5857	+	super(m, p, b);
5858	+	this.transformer = transformer; this.action = action;
5859	+	}
5860	+	public final void compute() {
5861	+	final BiFunction<? super K, ? super V, ? extends U> transformer;
5862	+	final Consumer<? super U> action;
5863	+	if ((transformer = this.transformer) != null &&
5864	+	(action = this.action) != null) {
5865	+	for (int b; (b = preSplit()) > 0;)
5866	+	new ForEachTransformedMappingTask<K,V,U>
5867	+	(map, this, b, transformer, action).fork();
5868	+	V v; U u;
5869	+	while ((v = advanceValue()) != null) {
5870	+	if ((u = transformer.apply(nextKey, v)) != null)
5871	+	action.accept(u);
5872	+	}
5873	+	propagateCompletion();
5874	+	}
5875	+	}
5876	+	}
5877	+
5878	+	@SuppressWarnings("serial") static final class SearchKeysTask<K,V,U>
5879	+	extends Traverser<K,V,U> {
5880	+	final Function<? super K, ? extends U> searchFunction;
5881	+	final AtomicReference<U> result;
5882	+	SearchKeysTask
5883	+	(ConcurrentHashMap<K,V> m, Traverser<K,V,?> p, int b,
5884	+	Function<? super K, ? extends U> searchFunction,
5885	+	AtomicReference<U> result) {
5886	+	super(m, p, b);
5887	+	this.searchFunction = searchFunction; this.result = result;
5888	+	}
5889	+	public final U getRawResult() { return result.get(); }
5890	+	public final void compute() {
5891	+	final Function<? super K, ? extends U> searchFunction;
5892	+	final AtomicReference<U> result;
5893	+	if ((searchFunction = this.searchFunction) != null &&
5894	+	(result = this.result) != null) {
5895	+	for (int b;;) {
5896	+	if (result.get() != null)
5897	+	return;
5898	+	if ((b = preSplit()) <= 0)
5899	+	break;
5900	+	new SearchKeysTask<K,V,U>
5901	+	(map, this, b, searchFunction, result).fork();
5902	+	}
5903	+	while (result.get() == null) {
5904	+	K k; U u;
5905	+	if ((k = advanceKey()) == null) {
5906	+	propagateCompletion();
5907	+	break;
5908	+	}
5909	+	if ((u = searchFunction.apply(k)) != null) {
5910	+	if (result.compareAndSet(null, u))
5911	+	quietlyCompleteRoot();
5912	+	break;
5913	+	}
5914	+	}
5915	+	}
5916	+	}
5917	+	}
5918	+
5919	+	@SuppressWarnings("serial") static final class SearchValuesTask<K,V,U>
5920	+	extends Traverser<K,V,U> {
5921	+	final Function<? super V, ? extends U> searchFunction;
5922	+	final AtomicReference<U> result;
5923	+	SearchValuesTask
5924	+	(ConcurrentHashMap<K,V> m, Traverser<K,V,?> p, int b,
5925	+	Function<? super V, ? extends U> searchFunction,
5926	+	AtomicReference<U> result) {
5927	+	super(m, p, b);
5928	+	this.searchFunction = searchFunction; this.result = result;
5929	+	}
5930	+	public final U getRawResult() { return result.get(); }
5931	+	public final void compute() {
5932	+	final Function<? super V, ? extends U> searchFunction;
5933	+	final AtomicReference<U> result;
5934	+	if ((searchFunction = this.searchFunction) != null &&
5935	+	(result = this.result) != null) {
5936	+	for (int b;;) {
5937	+	if (result.get() != null)
5938	+	return;
5939	+	if ((b = preSplit()) <= 0)
5940	+	break;
5941	+	new SearchValuesTask<K,V,U>
5942	+	(map, this, b, searchFunction, result).fork();
5943	+	}
5944	+	while (result.get() == null) {
5945	+	V v; U u;
5946	+	if ((v = advanceValue()) == null) {
5947	+	propagateCompletion();
5948	+	break;
5949	+	}
5950	+	if ((u = searchFunction.apply(v)) != null) {
5951	+	if (result.compareAndSet(null, u))
5952	+	quietlyCompleteRoot();
5953	+	break;
5954	+	}
5955	+	}
5956	+	}
5957	+	}
5958	+	}
5959	+
5960	+	@SuppressWarnings("serial") static final class SearchEntriesTask<K,V,U>
5961	+	extends Traverser<K,V,U> {
5962	+	final Function<Entry<K,V>, ? extends U> searchFunction;
5963	+	final AtomicReference<U> result;
5964	+	SearchEntriesTask
5965	+	(ConcurrentHashMap<K,V> m, Traverser<K,V,?> p, int b,
5966	+	Function<Entry<K,V>, ? extends U> searchFunction,
5967	+	AtomicReference<U> result) {
5968	+	super(m, p, b);
5969	+	this.searchFunction = searchFunction; this.result = result;
5970	+	}
5971	+	public final U getRawResult() { return result.get(); }
5972	+	public final void compute() {
5973	+	final Function<Entry<K,V>, ? extends U> searchFunction;
5974	+	final AtomicReference<U> result;
5975	+	if ((searchFunction = this.searchFunction) != null &&
5976	+	(result = this.result) != null) {
5977	+	for (int b;;) {
5978	+	if (result.get() != null)
5979	+	return;
5980	+	if ((b = preSplit()) <= 0)
5981	+	break;
5982	+	new SearchEntriesTask<K,V,U>
5983	+	(map, this, b, searchFunction, result).fork();
5984	+	}
5985	+	while (result.get() == null) {
5986	+	V v; U u;
5987	+	if ((v = advanceValue()) == null) {
5988	+	propagateCompletion();
5989	+	break;
5990	+	}
5991	+	if ((u = searchFunction.apply(entryFor(nextKey,
5992	+	v))) != null) {
5993	+	if (result.compareAndSet(null, u))
5994	+	quietlyCompleteRoot();
5995	+	return;
5996	+	}
5997	+	}
5998	+	}
5999	+	}
6000	+	}
6001	+
6002	+	@SuppressWarnings("serial") static final class SearchMappingsTask<K,V,U>
6003	+	extends Traverser<K,V,U> {
6004	+	final BiFunction<? super K, ? super V, ? extends U> searchFunction;
6005	+	final AtomicReference<U> result;
6006	+	SearchMappingsTask
6007	+	(ConcurrentHashMap<K,V> m, Traverser<K,V,?> p, int b,
6008	+	BiFunction<? super K, ? super V, ? extends U> searchFunction,
6009	+	AtomicReference<U> result) {
6010	+	super(m, p, b);
6011	+	this.searchFunction = searchFunction; this.result = result;
6012	+	}
6013	+	public final U getRawResult() { return result.get(); }
6014	+	public final void compute() {
6015	+	final BiFunction<? super K, ? super V, ? extends U> searchFunction;
6016	+	final AtomicReference<U> result;
6017	+	if ((searchFunction = this.searchFunction) != null &&
6018	+	(result = this.result) != null) {
6019	+	for (int b;;) {
6020	+	if (result.get() != null)
6021	+	return;
6022	+	if ((b = preSplit()) <= 0)
6023	+	break;
6024	+	new SearchMappingsTask<K,V,U>
6025	+	(map, this, b, searchFunction, result).fork();
6026	+	}
6027	+	while (result.get() == null) {
6028	+	V v; U u;
6029	+	if ((v = advanceValue()) == null) {
6030	+	propagateCompletion();
6031	+	break;
6032	+	}
6033	+	if ((u = searchFunction.apply(nextKey, v)) != null) {
6034	+	if (result.compareAndSet(null, u))
6035	+	quietlyCompleteRoot();
6036	+	break;
6037	+	}
6038	+	}
6039	+	}
6040	+	}
6041	+	}
6042	+
6043	+	@SuppressWarnings("serial") static final class ReduceKeysTask<K,V>
6044	+	extends Traverser<K,V,K> {
6045	+	final BiFunction<? super K, ? super K, ? extends K> reducer;
6046	+	K result;
6047	+	ReduceKeysTask<K,V> rights, nextRight;
6048	+	ReduceKeysTask
6049	+	(ConcurrentHashMap<K,V> m, Traverser<K,V,?> p, int b,
6050	+	ReduceKeysTask<K,V> nextRight,
6051	+	BiFunction<? super K, ? super K, ? extends K> reducer) {
6052	+	super(m, p, b); this.nextRight = nextRight;
6053	+	this.reducer = reducer;
6054	+	}
6055	+	public final K getRawResult() { return result; }
6056	+	@SuppressWarnings("unchecked") public final void compute() {
6057	+	final BiFunction<? super K, ? super K, ? extends K> reducer;
6058	+	if ((reducer = this.reducer) != null) {
6059	+	for (int b; (b = preSplit()) > 0;)
6060	+	(rights = new ReduceKeysTask<K,V>
6061	+	(map, this, b, rights, reducer)).fork();
6062	+	K u, r = null;
6063	+	while ((u = advanceKey()) != null) {
6064	+	r = (r == null) ? u : u == null ? r : reducer.apply(r, u);
6065	+	}
6066	+	result = r;
6067	+	CountedCompleter<?> c;
6068	+	for (c = firstComplete(); c != null; c = c.nextComplete()) {
6069	+	ReduceKeysTask<K,V>
6070	+	t = (ReduceKeysTask<K,V>)c,
6071	+	s = t.rights;
6072	+	while (s != null) {
6073	+	K tr, sr;
6074	+	if ((sr = s.result) != null)
6075	+	t.result = (((tr = t.result) == null) ? sr :
6076	+	reducer.apply(tr, sr));
6077	+	s = t.rights = s.nextRight;
6078	+	}
6079	+	}
6080	+	}
6081	+	}
6082	+	}
6083	+
6084	+	@SuppressWarnings("serial") static final class ReduceValuesTask<K,V>
6085	+	extends Traverser<K,V,V> {
6086	+	final BiFunction<? super V, ? super V, ? extends V> reducer;
6087	+	V result;
6088	+	ReduceValuesTask<K,V> rights, nextRight;
6089	+	ReduceValuesTask
6090	+	(ConcurrentHashMap<K,V> m, Traverser<K,V,?> p, int b,
6091	+	ReduceValuesTask<K,V> nextRight,
6092	+	BiFunction<? super V, ? super V, ? extends V> reducer) {
6093	+	super(m, p, b); this.nextRight = nextRight;
6094	+	this.reducer = reducer;
6095	+	}
6096	+	public final V getRawResult() { return result; }
6097	+	@SuppressWarnings("unchecked") public final void compute() {
6098	+	final BiFunction<? super V, ? super V, ? extends V> reducer;
6099	+	if ((reducer = this.reducer) != null) {
6100	+	for (int b; (b = preSplit()) > 0;)
6101	+	(rights = new ReduceValuesTask<K,V>
6102	+	(map, this, b, rights, reducer)).fork();
6103	+	V r = null, v;
6104	+	while ((v = advanceValue()) != null)
6105	+	r = (r == null) ? v : reducer.apply(r, v);
6106	+	result = r;
6107	+	CountedCompleter<?> c;
6108	+	for (c = firstComplete(); c != null; c = c.nextComplete()) {
6109	+	ReduceValuesTask<K,V>
6110	+	t = (ReduceValuesTask<K,V>)c,
6111	+	s = t.rights;
6112	+	while (s != null) {
6113	+	V tr, sr;
6114	+	if ((sr = s.result) != null)
6115	+	t.result = (((tr = t.result) == null) ? sr :
6116	+	reducer.apply(tr, sr));
6117	+	s = t.rights = s.nextRight;
6118	+	}
6119	+	}
6120	+	}
6121	+	}
6122	+	}
6123	+
6124	+	@SuppressWarnings("serial") static final class ReduceEntriesTask<K,V>
6125	+	extends Traverser<K,V,Map.Entry<K,V>> {
6126	+	final BiFunction<Map.Entry<K,V>, Map.Entry<K,V>, ? extends Map.Entry<K,V>> reducer;
6127	+	Map.Entry<K,V> result;
6128	+	ReduceEntriesTask<K,V> rights, nextRight;
6129	+	ReduceEntriesTask
6130	+	(ConcurrentHashMap<K,V> m, Traverser<K,V,?> p, int b,
6131	+	ReduceEntriesTask<K,V> nextRight,
6132	+	BiFunction<Entry<K,V>, Map.Entry<K,V>, ? extends Map.Entry<K,V>> reducer) {
6133	+	super(m, p, b); this.nextRight = nextRight;
6134	+	this.reducer = reducer;
6135	+	}
6136	+	public final Map.Entry<K,V> getRawResult() { return result; }
6137	+	@SuppressWarnings("unchecked") public final void compute() {
6138	+	final BiFunction<Map.Entry<K,V>, Map.Entry<K,V>, ? extends Map.Entry<K,V>> reducer;
6139	+	if ((reducer = this.reducer) != null) {
6140	+	for (int b; (b = preSplit()) > 0;)
6141	+	(rights = new ReduceEntriesTask<K,V>
6142	+	(map, this, b, rights, reducer)).fork();
6143	+	Map.Entry<K,V> r = null;
6144	+	V v;
6145	+	while ((v = advanceValue()) != null) {
6146	+	Map.Entry<K,V> u = entryFor(nextKey, v);
6147	+	r = (r == null) ? u : reducer.apply(r, u);
6148	+	}
6149	+	result = r;
6150	+	CountedCompleter<?> c;
6151	+	for (c = firstComplete(); c != null; c = c.nextComplete()) {
6152	+	ReduceEntriesTask<K,V>
6153	+	t = (ReduceEntriesTask<K,V>)c,
6154	+	s = t.rights;
6155	+	while (s != null) {
6156	+	Map.Entry<K,V> tr, sr;
6157	+	if ((sr = s.result) != null)
6158	+	t.result = (((tr = t.result) == null) ? sr :
6159	+	reducer.apply(tr, sr));
6160	+	s = t.rights = s.nextRight;
6161	+	}
6162	+	}
6163	+	}
6164	+	}
6165	+	}
6166	+
6167	+	@SuppressWarnings("serial") static final class MapReduceKeysTask<K,V,U>
6168	+	extends Traverser<K,V,U> {
6169	+	final Function<? super K, ? extends U> transformer;
6170	+	final BiFunction<? super U, ? super U, ? extends U> reducer;
6171	+	U result;
6172	+	MapReduceKeysTask<K,V,U> rights, nextRight;
6173	+	MapReduceKeysTask
6174	+	(ConcurrentHashMap<K,V> m, Traverser<K,V,?> p, int b,
6175	+	MapReduceKeysTask<K,V,U> nextRight,
6176	+	Function<? super K, ? extends U> transformer,
6177	+	BiFunction<? super U, ? super U, ? extends U> reducer) {
6178	+	super(m, p, b); this.nextRight = nextRight;
6179	+	this.transformer = transformer;
6180	+	this.reducer = reducer;
6181	+	}
6182	+	public final U getRawResult() { return result; }
6183	+	@SuppressWarnings("unchecked") public final void compute() {
6184	+	final Function<? super K, ? extends U> transformer;
6185	+	final BiFunction<? super U, ? super U, ? extends U> reducer;
6186	+	if ((transformer = this.transformer) != null &&
6187	+	(reducer = this.reducer) != null) {
6188	+	for (int b; (b = preSplit()) > 0;)
6189	+	(rights = new MapReduceKeysTask<K,V,U>
6190	+	(map, this, b, rights, transformer, reducer)).fork();
6191	+	K k; U r = null, u;
6192	+	while ((k = advanceKey()) != null) {
6193	+	if ((u = transformer.apply(k)) != null)
6194	+	r = (r == null) ? u : reducer.apply(r, u);
6195	+	}
6196	+	result = r;
6197	+	CountedCompleter<?> c;
6198	+	for (c = firstComplete(); c != null; c = c.nextComplete()) {
6199	+	MapReduceKeysTask<K,V,U>
6200	+	t = (MapReduceKeysTask<K,V,U>)c,
6201	+	s = t.rights;
6202	+	while (s != null) {
6203	+	U tr, sr;
6204	+	if ((sr = s.result) != null)
6205	+	t.result = (((tr = t.result) == null) ? sr :
6206	+	reducer.apply(tr, sr));
6207	+	s = t.rights = s.nextRight;
6208	+	}
6209	+	}
6210	+	}
6211	+	}
6212	+	}
6213	+
6214	+	@SuppressWarnings("serial") static final class MapReduceValuesTask<K,V,U>
6215	+	extends Traverser<K,V,U> {
6216	+	final Function<? super V, ? extends U> transformer;
6217	+	final BiFunction<? super U, ? super U, ? extends U> reducer;
6218	+	U result;
6219	+	MapReduceValuesTask<K,V,U> rights, nextRight;
6220	+	MapReduceValuesTask
6221	+	(ConcurrentHashMap<K,V> m, Traverser<K,V,?> p, int b,
6222	+	MapReduceValuesTask<K,V,U> nextRight,
6223	+	Function<? super V, ? extends U> transformer,
6224	+	BiFunction<? super U, ? super U, ? extends U> reducer) {
6225	+	super(m, p, b); this.nextRight = nextRight;
6226	+	this.transformer = transformer;
6227	+	this.reducer = reducer;
6228	+	}
6229	+	public final U getRawResult() { return result; }
6230	+	@SuppressWarnings("unchecked") public final void compute() {
6231	+	final Function<? super V, ? extends U> transformer;
6232	+	final BiFunction<? super U, ? super U, ? extends U> reducer;
6233	+	if ((transformer = this.transformer) != null &&
6234	+	(reducer = this.reducer) != null) {
6235	+	for (int b; (b = preSplit()) > 0;)
6236	+	(rights = new MapReduceValuesTask<K,V,U>
6237	+	(map, this, b, rights, transformer, reducer)).fork();
6238	+	U r = null, u;
6239	+	V v;
6240	+	while ((v = advanceValue()) != null) {
6241	+	if ((u = transformer.apply(v)) != null)
6242	+	r = (r == null) ? u : reducer.apply(r, u);
6243	+	}
6244	+	result = r;
6245	+	CountedCompleter<?> c;
6246	+	for (c = firstComplete(); c != null; c = c.nextComplete()) {
6247	+	MapReduceValuesTask<K,V,U>
6248	+	t = (MapReduceValuesTask<K,V,U>)c,
6249	+	s = t.rights;
6250	+	while (s != null) {
6251	+	U tr, sr;
6252	+	if ((sr = s.result) != null)
6253	+	t.result = (((tr = t.result) == null) ? sr :
6254	+	reducer.apply(tr, sr));
6255	+	s = t.rights = s.nextRight;
6256	+	}
6257	+	}
6258	+	}
6259	+	}
6260	+	}
6261	+
6262	+	@SuppressWarnings("serial") static final class MapReduceEntriesTask<K,V,U>
6263	+	extends Traverser<K,V,U> {
6264	+	final Function<Map.Entry<K,V>, ? extends U> transformer;
6265	+	final BiFunction<? super U, ? super U, ? extends U> reducer;
6266	+	U result;
6267	+	MapReduceEntriesTask<K,V,U> rights, nextRight;
6268	+	MapReduceEntriesTask
6269	+	(ConcurrentHashMap<K,V> m, Traverser<K,V,?> p, int b,
6270	+	MapReduceEntriesTask<K,V,U> nextRight,
6271	+	Function<Map.Entry<K,V>, ? extends U> transformer,
6272	+	BiFunction<? super U, ? super U, ? extends U> reducer) {
6273	+	super(m, p, b); this.nextRight = nextRight;
6274	+	this.transformer = transformer;
6275	+	this.reducer = reducer;
6276	+	}
6277	+	public final U getRawResult() { return result; }
6278	+	@SuppressWarnings("unchecked") public final void compute() {
6279	+	final Function<Map.Entry<K,V>, ? extends U> transformer;
6280	+	final BiFunction<? super U, ? super U, ? extends U> reducer;
6281	+	if ((transformer = this.transformer) != null &&
6282	+	(reducer = this.reducer) != null) {
6283	+	for (int b; (b = preSplit()) > 0;)
6284	+	(rights = new MapReduceEntriesTask<K,V,U>
6285	+	(map, this, b, rights, transformer, reducer)).fork();
6286	+	U r = null, u;
6287	+	V v;
6288	+	while ((v = advanceValue()) != null) {
6289	+	if ((u = transformer.apply(entryFor(nextKey,
6290	+	v))) != null)
6291	+	r = (r == null) ? u : reducer.apply(r, u);
6292	+	}
6293	+	result = r;
6294	+	CountedCompleter<?> c;
6295	+	for (c = firstComplete(); c != null; c = c.nextComplete()) {
6296	+	MapReduceEntriesTask<K,V,U>
6297	+	t = (MapReduceEntriesTask<K,V,U>)c,
6298	+	s = t.rights;
6299	+	while (s != null) {
6300	+	U tr, sr;
6301	+	if ((sr = s.result) != null)
6302	+	t.result = (((tr = t.result) == null) ? sr :
6303	+	reducer.apply(tr, sr));
6304	+	s = t.rights = s.nextRight;
6305	+	}
6306	+	}
6307	+	}
6308	+	}
6309	+	}
6310	+
6311	+	@SuppressWarnings("serial") static final class MapReduceMappingsTask<K,V,U>
6312	+	extends Traverser<K,V,U> {
6313	+	final BiFunction<? super K, ? super V, ? extends U> transformer;
6314	+	final BiFunction<? super U, ? super U, ? extends U> reducer;
6315	+	U result;
6316	+	MapReduceMappingsTask<K,V,U> rights, nextRight;
6317	+	MapReduceMappingsTask
6318	+	(ConcurrentHashMap<K,V> m, Traverser<K,V,?> p, int b,
6319	+	MapReduceMappingsTask<K,V,U> nextRight,
6320	+	BiFunction<? super K, ? super V, ? extends U> transformer,
6321	+	BiFunction<? super U, ? super U, ? extends U> reducer) {
6322	+	super(m, p, b); this.nextRight = nextRight;
6323	+	this.transformer = transformer;
6324	+	this.reducer = reducer;
6325	+	}
6326	+	public final U getRawResult() { return result; }
6327	+	@SuppressWarnings("unchecked") public final void compute() {
6328	+	final BiFunction<? super K, ? super V, ? extends U> transformer;
6329	+	final BiFunction<? super U, ? super U, ? extends U> reducer;
6330	+	if ((transformer = this.transformer) != null &&
6331	+	(reducer = this.reducer) != null) {
6332	+	for (int b; (b = preSplit()) > 0;)
6333	+	(rights = new MapReduceMappingsTask<K,V,U>
6334	+	(map, this, b, rights, transformer, reducer)).fork();
6335	+	U r = null, u;
6336	+	V v;
6337	+	while ((v = advanceValue()) != null) {
6338	+	if ((u = transformer.apply(nextKey, v)) != null)
6339	+	r = (r == null) ? u : reducer.apply(r, u);
6340	+	}
6341	+	result = r;
6342	+	CountedCompleter<?> c;
6343	+	for (c = firstComplete(); c != null; c = c.nextComplete()) {
6344	+	MapReduceMappingsTask<K,V,U>
6345	+	t = (MapReduceMappingsTask<K,V,U>)c,
6346	+	s = t.rights;
6347	+	while (s != null) {
6348	+	U tr, sr;
6349	+	if ((sr = s.result) != null)
6350	+	t.result = (((tr = t.result) == null) ? sr :
6351	+	reducer.apply(tr, sr));
6352	+	s = t.rights = s.nextRight;
6353	+	}
6354	+	}
6355	+	}
6356	+	}
6357	+	}
6358	+
6359	+	@SuppressWarnings("serial") static final class MapReduceKeysToDoubleTask<K,V>
6360	+	extends Traverser<K,V,Double> {
6361	+	final ToDoubleFunction<? super K> transformer;
6362	+	final DoubleBinaryOperator reducer;
6363	+	final double basis;
6364	+	double result;
6365	+	MapReduceKeysToDoubleTask<K,V> rights, nextRight;
6366	+	MapReduceKeysToDoubleTask
6367	+	(ConcurrentHashMap<K,V> m, Traverser<K,V,?> p, int b,
6368	+	MapReduceKeysToDoubleTask<K,V> nextRight,
6369	+	ToDoubleFunction<? super K> transformer,
6370	+	double basis,
6371	+	DoubleBinaryOperator reducer) {
6372	+	super(m, p, b); this.nextRight = nextRight;
6373	+	this.transformer = transformer;
6374	+	this.basis = basis; this.reducer = reducer;
6375	+	}
6376	+	public final Double getRawResult() { return result; }
6377	+	@SuppressWarnings("unchecked") public final void compute() {
6378	+	final ToDoubleFunction<? super K> transformer;
6379	+	final DoubleBinaryOperator reducer;
6380	+	if ((transformer = this.transformer) != null &&
6381	+	(reducer = this.reducer) != null) {
6382	+	double r = this.basis;
6383	+	for (int b; (b = preSplit()) > 0;)
6384	+	(rights = new MapReduceKeysToDoubleTask<K,V>
6385	+	(map, this, b, rights, transformer, r, reducer)).fork();
6386	+	K k;
6387	+	while ((k = advanceKey()) != null)
6388	+	r = reducer.applyAsDouble(r, transformer.applyAsDouble(k));
6389	+	result = r;
6390	+	CountedCompleter<?> c;
6391	+	for (c = firstComplete(); c != null; c = c.nextComplete()) {
6392	+	MapReduceKeysToDoubleTask<K,V>
6393	+	t = (MapReduceKeysToDoubleTask<K,V>)c,
6394	+	s = t.rights;
6395	+	while (s != null) {
6396	+	t.result = reducer.applyAsDouble(t.result, s.result);
6397	+	s = t.rights = s.nextRight;
6398	+	}
6399	+	}
6400	+	}
6401	+	}
6402	+	}
6403	+
6404	+	@SuppressWarnings("serial") static final class MapReduceValuesToDoubleTask<K,V>
6405	+	extends Traverser<K,V,Double> {
6406	+	final ToDoubleFunction<? super V> transformer;
6407	+	final DoubleBinaryOperator reducer;
6408	+	final double basis;
6409	+	double result;
6410	+	MapReduceValuesToDoubleTask<K,V> rights, nextRight;
6411	+	MapReduceValuesToDoubleTask
6412	+	(ConcurrentHashMap<K,V> m, Traverser<K,V,?> p, int b,
6413	+	MapReduceValuesToDoubleTask<K,V> nextRight,
6414	+	ToDoubleFunction<? super V> transformer,
6415	+	double basis,
6416	+	DoubleBinaryOperator reducer) {
6417	+	super(m, p, b); this.nextRight = nextRight;
6418	+	this.transformer = transformer;
6419	+	this.basis = basis; this.reducer = reducer;
6420	+	}
6421	+	public final Double getRawResult() { return result; }
6422	+	@SuppressWarnings("unchecked") public final void compute() {
6423	+	final ToDoubleFunction<? super V> transformer;
6424	+	final DoubleBinaryOperator reducer;
6425	+	if ((transformer = this.transformer) != null &&
6426	+	(reducer = this.reducer) != null) {
6427	+	double r = this.basis;
6428	+	for (int b; (b = preSplit()) > 0;)
6429	+	(rights = new MapReduceValuesToDoubleTask<K,V>
6430	+	(map, this, b, rights, transformer, r, reducer)).fork();
6431	+	V v;
6432	+	while ((v = advanceValue()) != null)
6433	+	r = reducer.applyAsDouble(r, transformer.applyAsDouble(v));
6434	+	result = r;
6435	+	CountedCompleter<?> c;
6436	+	for (c = firstComplete(); c != null; c = c.nextComplete()) {
6437	+	MapReduceValuesToDoubleTask<K,V>
6438	+	t = (MapReduceValuesToDoubleTask<K,V>)c,
6439	+	s = t.rights;
6440	+	while (s != null) {
6441	+	t.result = reducer.applyAsDouble(t.result, s.result);
6442	+	s = t.rights = s.nextRight;
6443	+	}
6444	+	}
6445	+	}
6446	+	}
6447	+	}
6448	+
6449	+	@SuppressWarnings("serial") static final class MapReduceEntriesToDoubleTask<K,V>
6450	+	extends Traverser<K,V,Double> {
6451	+	final ToDoubleFunction<Map.Entry<K,V>> transformer;
6452	+	final DoubleBinaryOperator reducer;
6453	+	final double basis;
6454	+	double result;
6455	+	MapReduceEntriesToDoubleTask<K,V> rights, nextRight;
6456	+	MapReduceEntriesToDoubleTask
6457	+	(ConcurrentHashMap<K,V> m, Traverser<K,V,?> p, int b,
6458	+	MapReduceEntriesToDoubleTask<K,V> nextRight,
6459	+	ToDoubleFunction<Map.Entry<K,V>> transformer,
6460	+	double basis,
6461	+	DoubleBinaryOperator reducer) {
6462	+	super(m, p, b); this.nextRight = nextRight;
6463	+	this.transformer = transformer;
6464	+	this.basis = basis; this.reducer = reducer;
6465	+	}
6466	+	public final Double getRawResult() { return result; }
6467	+	@SuppressWarnings("unchecked") public final void compute() {
6468	+	final ToDoubleFunction<Map.Entry<K,V>> transformer;
6469	+	final DoubleBinaryOperator reducer;
6470	+	if ((transformer = this.transformer) != null &&
6471	+	(reducer = this.reducer) != null) {
6472	+	double r = this.basis;
6473	+	for (int b; (b = preSplit()) > 0;)
6474	+	(rights = new MapReduceEntriesToDoubleTask<K,V>
6475	+	(map, this, b, rights, transformer, r, reducer)).fork();
6476	+	V v;
6477	+	while ((v = advanceValue()) != null)
6478	+	r = reducer.applyAsDouble(r, transformer.applyAsDouble(entryFor(nextKey,
6479	+	v)));
6480	+	result = r;
6481	+	CountedCompleter<?> c;
6482	+	for (c = firstComplete(); c != null; c = c.nextComplete()) {
6483	+	MapReduceEntriesToDoubleTask<K,V>
6484	+	t = (MapReduceEntriesToDoubleTask<K,V>)c,
6485	+	s = t.rights;
6486	+	while (s != null) {
6487	+	t.result = reducer.applyAsDouble(t.result, s.result);
6488	+	s = t.rights = s.nextRight;
6489	+	}
6490	+	}
6491	+	}
6492	+	}
6493	+	}
6494	+
6495	+	@SuppressWarnings("serial") static final class MapReduceMappingsToDoubleTask<K,V>
6496	+	extends Traverser<K,V,Double> {
6497	+	final ToDoubleBiFunction<? super K, ? super V> transformer;
6498	+	final DoubleBinaryOperator reducer;
6499	+	final double basis;
6500	+	double result;
6501	+	MapReduceMappingsToDoubleTask<K,V> rights, nextRight;
6502	+	MapReduceMappingsToDoubleTask
6503	+	(ConcurrentHashMap<K,V> m, Traverser<K,V,?> p, int b,
6504	+	MapReduceMappingsToDoubleTask<K,V> nextRight,
6505	+	ToDoubleBiFunction<? super K, ? super V> transformer,
6506	+	double basis,
6507	+	DoubleBinaryOperator reducer) {
6508	+	super(m, p, b); this.nextRight = nextRight;
6509	+	this.transformer = transformer;
6510	+	this.basis = basis; this.reducer = reducer;
6511	+	}
6512	+	public final Double getRawResult() { return result; }
6513	+	@SuppressWarnings("unchecked") public final void compute() {
6514	+	final ToDoubleBiFunction<? super K, ? super V> transformer;
6515	+	final DoubleBinaryOperator reducer;
6516	+	if ((transformer = this.transformer) != null &&
6517	+	(reducer = this.reducer) != null) {
6518	+	double r = this.basis;
6519	+	for (int b; (b = preSplit()) > 0;)
6520	+	(rights = new MapReduceMappingsToDoubleTask<K,V>
6521	+	(map, this, b, rights, transformer, r, reducer)).fork();
6522	+	V v;
6523	+	while ((v = advanceValue()) != null)
6524	+	r = reducer.applyAsDouble(r, transformer.applyAsDouble(nextKey, v));
6525	+	result = r;
6526	+	CountedCompleter<?> c;
6527	+	for (c = firstComplete(); c != null; c = c.nextComplete()) {
6528	+	MapReduceMappingsToDoubleTask<K,V>
6529	+	t = (MapReduceMappingsToDoubleTask<K,V>)c,
6530	+	s = t.rights;
6531	+	while (s != null) {
6532	+	t.result = reducer.applyAsDouble(t.result, s.result);
6533	+	s = t.rights = s.nextRight;
6534	+	}
6535	+	}
6536	+	}
6537	+	}
6538	+	}
6539	+
6540	+	@SuppressWarnings("serial") static final class MapReduceKeysToLongTask<K,V>
6541	+	extends Traverser<K,V,Long> {
6542	+	final ToLongFunction<? super K> transformer;
6543	+	final LongBinaryOperator reducer;
6544	+	final long basis;
6545	+	long result;
6546	+	MapReduceKeysToLongTask<K,V> rights, nextRight;
6547	+	MapReduceKeysToLongTask
6548	+	(ConcurrentHashMap<K,V> m, Traverser<K,V,?> p, int b,
6549	+	MapReduceKeysToLongTask<K,V> nextRight,
6550	+	ToLongFunction<? super K> transformer,
6551	+	long basis,
6552	+	LongBinaryOperator reducer) {
6553	+	super(m, p, b); this.nextRight = nextRight;
6554	+	this.transformer = transformer;
6555	+	this.basis = basis; this.reducer = reducer;
6556	+	}
6557	+	public final Long getRawResult() { return result; }
6558	+	@SuppressWarnings("unchecked") public final void compute() {
6559	+	final ToLongFunction<? super K> transformer;
6560	+	final LongBinaryOperator reducer;
6561	+	if ((transformer = this.transformer) != null &&
6562	+	(reducer = this.reducer) != null) {
6563	+	long r = this.basis;
6564	+	for (int b; (b = preSplit()) > 0;)
6565	+	(rights = new MapReduceKeysToLongTask<K,V>
6566	+	(map, this, b, rights, transformer, r, reducer)).fork();
6567	+	K k;
6568	+	while ((k = advanceKey()) != null)
6569	+	r = reducer.applyAsLong(r, transformer.applyAsLong(k));
6570	+	result = r;
6571	+	CountedCompleter<?> c;
6572	+	for (c = firstComplete(); c != null; c = c.nextComplete()) {
6573	+	MapReduceKeysToLongTask<K,V>
6574	+	t = (MapReduceKeysToLongTask<K,V>)c,
6575	+	s = t.rights;
6576	+	while (s != null) {
6577	+	t.result = reducer.applyAsLong(t.result, s.result);
6578	+	s = t.rights = s.nextRight;
6579	+	}
6580	+	}
6581	+	}
6582	+	}
6583	+	}
6584	+
6585	+	@SuppressWarnings("serial") static final class MapReduceValuesToLongTask<K,V>
6586	+	extends Traverser<K,V,Long> {
6587	+	final ToLongFunction<? super V> transformer;
6588	+	final LongBinaryOperator reducer;
6589	+	final long basis;
6590	+	long result;
6591	+	MapReduceValuesToLongTask<K,V> rights, nextRight;
6592	+	MapReduceValuesToLongTask
6593	+	(ConcurrentHashMap<K,V> m, Traverser<K,V,?> p, int b,
6594	+	MapReduceValuesToLongTask<K,V> nextRight,
6595	+	ToLongFunction<? super V> transformer,
6596	+	long basis,
6597	+	LongBinaryOperator reducer) {
6598	+	super(m, p, b); this.nextRight = nextRight;
6599	+	this.transformer = transformer;
6600	+	this.basis = basis; this.reducer = reducer;
6601	+	}
6602	+	public final Long getRawResult() { return result; }
6603	+	@SuppressWarnings("unchecked") public final void compute() {
6604	+	final ToLongFunction<? super V> transformer;
6605	+	final LongBinaryOperator reducer;
6606	+	if ((transformer = this.transformer) != null &&
6607	+	(reducer = this.reducer) != null) {
6608	+	long r = this.basis;
6609	+	for (int b; (b = preSplit()) > 0;)
6610	+	(rights = new MapReduceValuesToLongTask<K,V>
6611	+	(map, this, b, rights, transformer, r, reducer)).fork();
6612	+	V v;
6613	+	while ((v = advanceValue()) != null)
6614	+	r = reducer.applyAsLong(r, transformer.applyAsLong(v));
6615	+	result = r;
6616	+	CountedCompleter<?> c;
6617	+	for (c = firstComplete(); c != null; c = c.nextComplete()) {
6618	+	MapReduceValuesToLongTask<K,V>
6619	+	t = (MapReduceValuesToLongTask<K,V>)c,
6620	+	s = t.rights;
6621	+	while (s != null) {
6622	+	t.result = reducer.applyAsLong(t.result, s.result);
6623	+	s = t.rights = s.nextRight;
6624	+	}
6625	+	}
6626	+	}
6627	+	}
6628	+	}
6629	+
6630	+	@SuppressWarnings("serial") static final class MapReduceEntriesToLongTask<K,V>
6631	+	extends Traverser<K,V,Long> {
6632	+	final ToLongFunction<Map.Entry<K,V>> transformer;
6633	+	final LongBinaryOperator reducer;
6634	+	final long basis;
6635	+	long result;
6636	+	MapReduceEntriesToLongTask<K,V> rights, nextRight;
6637	+	MapReduceEntriesToLongTask
6638	+	(ConcurrentHashMap<K,V> m, Traverser<K,V,?> p, int b,
6639	+	MapReduceEntriesToLongTask<K,V> nextRight,
6640	+	ToLongFunction<Map.Entry<K,V>> transformer,
6641	+	long basis,
6642	+	LongBinaryOperator reducer) {
6643	+	super(m, p, b); this.nextRight = nextRight;
6644	+	this.transformer = transformer;
6645	+	this.basis = basis; this.reducer = reducer;
6646	+	}
6647	+	public final Long getRawResult() { return result; }
6648	+	@SuppressWarnings("unchecked") public final void compute() {
6649	+	final ToLongFunction<Map.Entry<K,V>> transformer;
6650	+	final LongBinaryOperator reducer;
6651	+	if ((transformer = this.transformer) != null &&
6652	+	(reducer = this.reducer) != null) {
6653	+	long r = this.basis;
6654	+	for (int b; (b = preSplit()) > 0;)
6655	+	(rights = new MapReduceEntriesToLongTask<K,V>
6656	+	(map, this, b, rights, transformer, r, reducer)).fork();
6657	+	V v;
6658	+	while ((v = advanceValue()) != null)
6659	+	r = reducer.applyAsLong(r, transformer.applyAsLong(entryFor(nextKey, v)));
6660	+	result = r;
6661	+	CountedCompleter<?> c;
6662	+	for (c = firstComplete(); c != null; c = c.nextComplete()) {
6663	+	MapReduceEntriesToLongTask<K,V>
6664	+	t = (MapReduceEntriesToLongTask<K,V>)c,
6665	+	s = t.rights;
6666	+	while (s != null) {
6667	+	t.result = reducer.applyAsLong(t.result, s.result);
6668	+	s = t.rights = s.nextRight;
6669	+	}
6670	+	}
6671	+	}
6672	+	}
6673	+	}
6674	+
6675	+	@SuppressWarnings("serial") static final class MapReduceMappingsToLongTask<K,V>
6676	+	extends Traverser<K,V,Long> {
6677	+	final ToLongBiFunction<? super K, ? super V> transformer;
6678	+	final LongBinaryOperator reducer;
6679	+	final long basis;
6680	+	long result;
6681	+	MapReduceMappingsToLongTask<K,V> rights, nextRight;
6682	+	MapReduceMappingsToLongTask
6683	+	(ConcurrentHashMap<K,V> m, Traverser<K,V,?> p, int b,
6684	+	MapReduceMappingsToLongTask<K,V> nextRight,
6685	+	ToLongBiFunction<? super K, ? super V> transformer,
6686	+	long basis,
6687	+	LongBinaryOperator reducer) {
6688	+	super(m, p, b); this.nextRight = nextRight;
6689	+	this.transformer = transformer;
6690	+	this.basis = basis; this.reducer = reducer;
6691	+	}
6692	+	public final Long getRawResult() { return result; }
6693	+	@SuppressWarnings("unchecked") public final void compute() {
6694	+	final ToLongBiFunction<? super K, ? super V> transformer;
6695	+	final LongBinaryOperator reducer;
6696	+	if ((transformer = this.transformer) != null &&
6697	+	(reducer = this.reducer) != null) {
6698	+	long r = this.basis;
6699	+	for (int b; (b = preSplit()) > 0;)
6700	+	(rights = new MapReduceMappingsToLongTask<K,V>
6701	+	(map, this, b, rights, transformer, r, reducer)).fork();
6702	+	V v;
6703	+	while ((v = advanceValue()) != null)
6704	+	r = reducer.applyAsLong(r, transformer.applyAsLong(nextKey, v));
6705	+	result = r;
6706	+	CountedCompleter<?> c;
6707	+	for (c = firstComplete(); c != null; c = c.nextComplete()) {
6708	+	MapReduceMappingsToLongTask<K,V>
6709	+	t = (MapReduceMappingsToLongTask<K,V>)c,
6710	+	s = t.rights;
6711	+	while (s != null) {
6712	+	t.result = reducer.applyAsLong(t.result, s.result);
6713	+	s = t.rights = s.nextRight;
6714	+	}
6715	+	}
6716	+	}
6717	+	}
6718	+	}
6719	+
6720	+	@SuppressWarnings("serial") static final class MapReduceKeysToIntTask<K,V>
6721	+	extends Traverser<K,V,Integer> {
6722	+	final ToIntFunction<? super K> transformer;
6723	+	final IntBinaryOperator reducer;
6724	+	final int basis;
6725	+	int result;
6726	+	MapReduceKeysToIntTask<K,V> rights, nextRight;
6727	+	MapReduceKeysToIntTask
6728	+	(ConcurrentHashMap<K,V> m, Traverser<K,V,?> p, int b,
6729	+	MapReduceKeysToIntTask<K,V> nextRight,
6730	+	ToIntFunction<? super K> transformer,
6731	+	int basis,
6732	+	IntBinaryOperator reducer) {
6733	+	super(m, p, b); this.nextRight = nextRight;
6734	+	this.transformer = transformer;
6735	+	this.basis = basis; this.reducer = reducer;
6736	+	}
6737	+	public final Integer getRawResult() { return result; }
6738	+	@SuppressWarnings("unchecked") public final void compute() {
6739	+	final ToIntFunction<? super K> transformer;
6740	+	final IntBinaryOperator reducer;
6741	+	if ((transformer = this.transformer) != null &&
6742	+	(reducer = this.reducer) != null) {
6743	+	int r = this.basis;
6744	+	for (int b; (b = preSplit()) > 0;)
6745	+	(rights = new MapReduceKeysToIntTask<K,V>
6746	+	(map, this, b, rights, transformer, r, reducer)).fork();
6747	+	K k;
6748	+	while ((k = advanceKey()) != null)
6749	+	r = reducer.applyAsInt(r, transformer.applyAsInt(k));
6750	+	result = r;
6751	+	CountedCompleter<?> c;
6752	+	for (c = firstComplete(); c != null; c = c.nextComplete()) {
6753	+	MapReduceKeysToIntTask<K,V>
6754	+	t = (MapReduceKeysToIntTask<K,V>)c,
6755	+	s = t.rights;
6756	+	while (s != null) {
6757	+	t.result = reducer.applyAsInt(t.result, s.result);
6758	+	s = t.rights = s.nextRight;
6759	+	}
6760	+	}
6761	+	}
6762	+	}
6763	+	}
6764	+
6765	+	@SuppressWarnings("serial") static final class MapReduceValuesToIntTask<K,V>
6766	+	extends Traverser<K,V,Integer> {
6767	+	final ToIntFunction<? super V> transformer;
6768	+	final IntBinaryOperator reducer;
6769	+	final int basis;
6770	+	int result;
6771	+	MapReduceValuesToIntTask<K,V> rights, nextRight;
6772	+	MapReduceValuesToIntTask
6773	+	(ConcurrentHashMap<K,V> m, Traverser<K,V,?> p, int b,
6774	+	MapReduceValuesToIntTask<K,V> nextRight,
6775	+	ToIntFunction<? super V> transformer,
6776	+	int basis,
6777	+	IntBinaryOperator reducer) {
6778	+	super(m, p, b); this.nextRight = nextRight;
6779	+	this.transformer = transformer;
6780	+	this.basis = basis; this.reducer = reducer;
6781	+	}
6782	+	public final Integer getRawResult() { return result; }
6783	+	@SuppressWarnings("unchecked") public final void compute() {
6784	+	final ToIntFunction<? super V> transformer;
6785	+	final IntBinaryOperator reducer;
6786	+	if ((transformer = this.transformer) != null &&
6787	+	(reducer = this.reducer) != null) {
6788	+	int r = this.basis;
6789	+	for (int b; (b = preSplit()) > 0;)
6790	+	(rights = new MapReduceValuesToIntTask<K,V>
6791	+	(map, this, b, rights, transformer, r, reducer)).fork();
6792	+	V v;
6793	+	while ((v = advanceValue()) != null)
6794	+	r = reducer.applyAsInt(r, transformer.applyAsInt(v));
6795	+	result = r;
6796	+	CountedCompleter<?> c;
6797	+	for (c = firstComplete(); c != null; c = c.nextComplete()) {
6798	+	MapReduceValuesToIntTask<K,V>
6799	+	t = (MapReduceValuesToIntTask<K,V>)c,
6800	+	s = t.rights;
6801	+	while (s != null) {
6802	+	t.result = reducer.applyAsInt(t.result, s.result);
6803	+	s = t.rights = s.nextRight;
6804	+	}
6805	+	}
6806	+	}
6807	+	}
6808	+	}
6809	+
6810	+	@SuppressWarnings("serial") static final class MapReduceEntriesToIntTask<K,V>
6811	+	extends Traverser<K,V,Integer> {
6812	+	final ToIntFunction<Map.Entry<K,V>> transformer;
6813	+	final IntBinaryOperator reducer;
6814	+	final int basis;
6815	+	int result;
6816	+	MapReduceEntriesToIntTask<K,V> rights, nextRight;
6817	+	MapReduceEntriesToIntTask
6818	+	(ConcurrentHashMap<K,V> m, Traverser<K,V,?> p, int b,
6819	+	MapReduceEntriesToIntTask<K,V> nextRight,
6820	+	ToIntFunction<Map.Entry<K,V>> transformer,
6821	+	int basis,
6822	+	IntBinaryOperator reducer) {
6823	+	super(m, p, b); this.nextRight = nextRight;
6824	+	this.transformer = transformer;
6825	+	this.basis = basis; this.reducer = reducer;
6826	+	}
6827	+	public final Integer getRawResult() { return result; }
6828	+	@SuppressWarnings("unchecked") public final void compute() {
6829	+	final ToIntFunction<Map.Entry<K,V>> transformer;
6830	+	final IntBinaryOperator reducer;
6831	+	if ((transformer = this.transformer) != null &&
6832	+	(reducer = this.reducer) != null) {
6833	+	int r = this.basis;
6834	+	for (int b; (b = preSplit()) > 0;)
6835	+	(rights = new MapReduceEntriesToIntTask<K,V>
6836	+	(map, this, b, rights, transformer, r, reducer)).fork();
6837	+	V v;
6838	+	while ((v = advanceValue()) != null)
6839	+	r = reducer.applyAsInt(r, transformer.applyAsInt(entryFor(nextKey,
6840	+	v)));
6841	+	result = r;
6842	+	CountedCompleter<?> c;
6843	+	for (c = firstComplete(); c != null; c = c.nextComplete()) {
6844	+	MapReduceEntriesToIntTask<K,V>
6845	+	t = (MapReduceEntriesToIntTask<K,V>)c,
6846	+	s = t.rights;
6847	+	while (s != null) {
6848	+	t.result = reducer.applyAsInt(t.result, s.result);
6849	+	s = t.rights = s.nextRight;
6850	+	}
6851	+	}
6852	+	}
6853	+	}
6854	+	}
6855	+
6856	+	@SuppressWarnings("serial") static final class MapReduceMappingsToIntTask<K,V>
6857	+	extends Traverser<K,V,Integer> {
6858	+	final ToIntBiFunction<? super K, ? super V> transformer;
6859	+	final IntBinaryOperator reducer;
6860	+	final int basis;
6861	+	int result;
6862	+	MapReduceMappingsToIntTask<K,V> rights, nextRight;
6863	+	MapReduceMappingsToIntTask
6864	+	(ConcurrentHashMap<K,V> m, Traverser<K,V,?> p, int b,
6865	+	MapReduceMappingsToIntTask<K,V> nextRight,
6866	+	ToIntBiFunction<? super K, ? super V> transformer,
6867	+	int basis,
6868	+	IntBinaryOperator reducer) {
6869	+	super(m, p, b); this.nextRight = nextRight;
6870	+	this.transformer = transformer;
6871	+	this.basis = basis; this.reducer = reducer;
6872	+	}
6873	+	public final Integer getRawResult() { return result; }
6874	+	@SuppressWarnings("unchecked") public final void compute() {
6875	+	final ToIntBiFunction<? super K, ? super V> transformer;
6876	+	final IntBinaryOperator reducer;
6877	+	if ((transformer = this.transformer) != null &&
6878	+	(reducer = this.reducer) != null) {
6879	+	int r = this.basis;
6880	+	for (int b; (b = preSplit()) > 0;)
6881	+	(rights = new MapReduceMappingsToIntTask<K,V>
6882	+	(map, this, b, rights, transformer, r, reducer)).fork();
6883	+	V v;
6884	+	while ((v = advanceValue()) != null)
6885	+	r = reducer.applyAsInt(r, transformer.applyAsInt(nextKey, v));
6886	+	result = r;
6887	+	CountedCompleter<?> c;
6888	+	for (c = firstComplete(); c != null; c = c.nextComplete()) {
6889	+	MapReduceMappingsToIntTask<K,V>
6890	+	t = (MapReduceMappingsToIntTask<K,V>)c,
6891	+	s = t.rights;
6892	+	while (s != null) {
6893	+	t.result = reducer.applyAsInt(t.result, s.result);
6894	+	s = t.rights = s.nextRight;
6895	+	}
6896	+	}
6897	+	}
6898	+	}
6899	+	}
6900	+
6901	+	// Unsafe mechanics
6902	+	private static final sun.misc.Unsafe U;
6903	+	private static final long SIZECTL;
6904	+	private static final long TRANSFERINDEX;
6905	+	private static final long TRANSFERORIGIN;
6906	+	private static final long BASECOUNT;
6907	+	private static final long CELLSBUSY;
6908	+	private static final long CELLVALUE;
6909	+	private static final long ABASE;
6910	+	private static final int ASHIFT;
6911	+
6912	+	static {
6913	+	try {
6914	+	U = sun.misc.Unsafe.getUnsafe();
6915	+	Class<?> k = ConcurrentHashMap.class;
6916	+	SIZECTL = U.objectFieldOffset
6917	+	(k.getDeclaredField("sizeCtl"));
6918	+	TRANSFERINDEX = U.objectFieldOffset
6919	+	(k.getDeclaredField("transferIndex"));
6920	+	TRANSFERORIGIN = U.objectFieldOffset
6921	+	(k.getDeclaredField("transferOrigin"));
6922	+	BASECOUNT = U.objectFieldOffset
6923	+	(k.getDeclaredField("baseCount"));
6924	+	CELLSBUSY = U.objectFieldOffset
6925	+	(k.getDeclaredField("cellsBusy"));
6926	+	Class<?> ck = Cell.class;
6927	+	CELLVALUE = U.objectFieldOffset
6928	+	(ck.getDeclaredField("value"));
6929	+	Class<?> sc = Node[].class;
6930	+	ABASE = U.arrayBaseOffset(sc);
6931	+	int scale = U.arrayIndexScale(sc);
6932	+	if ((scale & (scale - 1)) != 0)
6933	+	throw new Error("data type scale not a power of two");
6934	+	ASHIFT = 31 - Integer.numberOfLeadingZeros(scale);
6935	+	} catch (Exception e) {
6936	+	throw new Error(e);
6937	+	}
6938	+	}
6939	+
6940		}

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