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Comparing jsr166/src/main/java/util/concurrent/ConcurrentHashMap.java (file contents):
Revision 1.89 by dl, Tue Jun 6 11:17:58 2006 UTC vs.
Revision 1.274 by jsr166, Sun Sep 6 00:57:56 2015 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	>
9	>	import java.io.ObjectStreamField;
10		import java.io.Serializable;
11	<	import java.io.IOException;
12	<	import java.io.ObjectInputStream;
13	<	import java.io.ObjectOutputStream;
11	>	import java.lang.reflect.ParameterizedType;
12	>	import java.lang.reflect.Type;
13	>	import java.util.AbstractMap;
14	>	import java.util.Arrays;
15	>	import java.util.Collection;
16	>	import java.util.Enumeration;
17	>	import java.util.HashMap;
18	>	import java.util.Hashtable;
19	>	import java.util.Iterator;
20	>	import java.util.Map;
21	>	import java.util.NoSuchElementException;
22	>	import java.util.Set;
23	>	import java.util.Spliterator;
24	>	import java.util.concurrent.atomic.AtomicReference;
25	>	import java.util.concurrent.locks.LockSupport;
26	>	import java.util.concurrent.locks.ReentrantLock;
27	>	import java.util.function.BiConsumer;
28	>	import java.util.function.BiFunction;
29	>	import java.util.function.Consumer;
30	>	import java.util.function.DoubleBinaryOperator;
31	>	import java.util.function.Function;
32	>	import java.util.function.IntBinaryOperator;
33	>	import java.util.function.LongBinaryOperator;
34	>	import java.util.function.Predicate;
35	>	import java.util.function.ToDoubleBiFunction;
36	>	import java.util.function.ToDoubleFunction;
37	>	import java.util.function.ToIntBiFunction;
38	>	import java.util.function.ToIntFunction;
39	>	import java.util.function.ToLongBiFunction;
40	>	import java.util.function.ToLongFunction;
41	>	import java.util.stream.Stream;
42
43		/**
44		* A hash table supporting full concurrency of retrievals and
45	<	* adjustable expected concurrency for updates. This class obeys the
45	>	* high expected concurrency for updates. This class obeys the
46		* same functional specification as {@link java.util.Hashtable}, and
47		* includes versions of methods corresponding to each method of
48	<	* <tt>Hashtable</tt>. However, even though all operations are
48	>	* {@code Hashtable}. However, even though all operations are
49		* thread-safe, retrieval operations do <em>not</em> entail locking,
50		* and there is <em>not</em> any support for locking the entire table
51		* in a way that prevents all access.  This class is fully
52	<	* interoperable with <tt>Hashtable</tt> in programs that rely on its
52	>	* interoperable with {@code Hashtable} in programs that rely on its
53		* thread safety but not on its synchronization details.
54		*
55	<	* <p> Retrieval operations (including <tt>get</tt>) generally do not
56	<	* block, so may overlap with update operations (including
57	<	* <tt>put</tt> and <tt>remove</tt>). Retrievals reflect the results
58	<	* of the most recently <em>completed</em> update operations holding
59	<	* upon their onset.  For aggregate operations such as <tt>putAll</tt>
60	<	* and <tt>clear</tt>, concurrent retrievals may reflect insertion or
61	<	* removal of only some entries.  Similarly, Iterators and
62	<	* Enumerations return elements reflecting the state of the hash table
63	<	* at some point at or since the creation of the iterator/enumeration.
64	<	* They do <em>not</em> throw {@link ConcurrentModificationException}.
55	>	* <p>Retrieval operations (including {@code get}) generally do not
56	>	* block, so may overlap with update operations (including {@code put}
57	>	* and {@code remove}). Retrievals reflect the results of the most
58	>	* recently <em>completed</em> update operations holding upon their
59	>	* onset. (More formally, an update operation for a given key bears a
60	>	* <em>happens-before</em> relation with any (non-null) retrieval for
61	>	* that key reporting the updated value.)  For aggregate operations
62	>	* such as {@code putAll} and {@code clear}, concurrent retrievals may
63	>	* reflect insertion or removal of only some entries.  Similarly,
64	>	* Iterators, Spliterators and Enumerations return elements reflecting the
65	>	* state of the hash table at some point at or since the creation of the
66	>	* iterator/enumeration.  They do <em>not</em> throw {@link
67	>	* java.util.ConcurrentModificationException ConcurrentModificationException}.
68		* However, iterators are designed to be used by only one thread at a time.
69	+	* Bear in mind that the results of aggregate status methods including
70	+	* {@code size}, {@code isEmpty}, and {@code containsValue} are typically
71	+	* useful only when a map is not undergoing concurrent updates in other threads.
72	+	* Otherwise the results of these methods reflect transient states
73	+	* that may be adequate for monitoring or estimation purposes, but not
74	+	* for program control.
75	+	*
76	+	* <p>The table is dynamically expanded when there are too many
77	+	* collisions (i.e., keys that have distinct hash codes but fall into
78	+	* the same slot modulo the table size), with the expected average
79	+	* effect of maintaining roughly two bins per mapping (corresponding
80	+	* to a 0.75 load factor threshold for resizing). There may be much
81	+	* variance around this average as mappings are added and removed, but
82	+	* overall, this maintains a commonly accepted time/space tradeoff for
83	+	* hash tables.  However, resizing this or any other kind of hash
84	+	* table may be a relatively slow operation. When possible, it is a
85	+	* good idea to provide a size estimate as an optional {@code
86	+	* initialCapacity} constructor argument. An additional optional
87	+	* {@code loadFactor} constructor argument provides a further means of
88	+	* customizing initial table capacity by specifying the table density
89	+	* to be used in calculating the amount of space to allocate for the
90	+	* given number of elements.  Also, for compatibility with previous
91	+	* versions of this class, constructors may optionally specify an
92	+	* expected {@code concurrencyLevel} as an additional hint for
93	+	* internal sizing.  Note that using many keys with exactly the same
94	+	* {@code hashCode()} is a sure way to slow down performance of any
95	+	* hash table. To ameliorate impact, when keys are {@link Comparable},
96	+	* this class may use comparison order among keys to help break ties.
97	+	*
98	+	* <p>A {@link Set} projection of a ConcurrentHashMap may be created
99	+	* (using {@link #newKeySet()} or {@link #newKeySet(int)}), or viewed
100	+	* (using {@link #keySet(Object)} when only keys are of interest, and the
101	+	* mapped values are (perhaps transiently) not used or all take the
102	+	* same mapping value.
103		*
104	<	* <p> The allowed concurrency among update operations is guided by
105	<	* the optional <tt>concurrencyLevel</tt> constructor argument
106	<	* (default <tt>16</tt>), which is used as a hint for internal sizing.  The
107	<	* table is internally partitioned to try to permit the indicated
108	<	* number of concurrent updates without contention. Because placement
109	<	* in hash tables is essentially random, the actual concurrency will
45	<	* vary.  Ideally, you should choose a value to accommodate as many
46	<	* threads as will ever concurrently modify the table. Using a
47	<	* significantly higher value than you need can waste space and time,
48	<	* and a significantly lower value can lead to thread contention. But
49	<	* overestimates and underestimates within an order of magnitude do
50	<	* not usually have much noticeable impact. A value of one is
51	<	* appropriate when it is known that only one thread will modify and
52	<	* all others will only read. Also, resizing this or any other kind of
53	<	* hash table is a relatively slow operation, so, when possible, it is
54	<	* a good idea to provide estimates of expected table sizes in
55	<	* constructors.
104	>	* <p>A ConcurrentHashMap can be used as a scalable frequency map (a
105	>	* form of histogram or multiset) by using {@link
106	>	* java.util.concurrent.atomic.LongAdder} values and initializing via
107	>	* {@link #computeIfAbsent computeIfAbsent}. For example, to add a count
108	>	* to a {@code ConcurrentHashMap<String,LongAdder> freqs}, you can use
109	>	* {@code freqs.computeIfAbsent(key, k -> new LongAdder()).increment();}
110		*
111		* <p>This class and its views and iterators implement all of the
112		* <em>optional</em> methods of the {@link Map} and {@link Iterator}
113		* interfaces.
114		*
115	<	* <p> Like {@link Hashtable} but unlike {@link HashMap}, this class
116	<	* does <em>not</em> allow <tt>null</tt> to be used as a key or value.
115	>	* <p>Like {@link Hashtable} but unlike {@link HashMap}, this class
116	>	* does <em>not</em> allow {@code null} to be used as a key or value.
117	>	*
118	>	* <p>ConcurrentHashMaps support a set of sequential and parallel bulk
119	>	* operations that, unlike most {@link Stream} methods, are designed
120	>	* to be safely, and often sensibly, applied even with maps that are
121	>	* being concurrently updated by other threads; for example, when
122	>	* computing a snapshot summary of the values in a shared registry.
123	>	* There are three kinds of operation, each with four forms, accepting
124	>	* functions with Keys, Values, Entries, and (Key, Value) arguments
125	>	* and/or return values. Because the elements of a ConcurrentHashMap
126	>	* are not ordered in any particular way, and may be processed in
127	>	* different orders in different parallel executions, the correctness
128	>	* of supplied functions should not depend on any ordering, or on any
129	>	* other objects or values that may transiently change while
130	>	* computation is in progress; and except for forEach actions, should
131	>	* ideally be side-effect-free. Bulk operations on {@link java.util.Map.Entry}
132	>	* objects do not support method {@code setValue}.
133	>	*
134	>	* <ul>
135	>	* <li> forEach: Perform a given action on each element.
136	>	* A variant form applies a given transformation on each element
137	>	* before performing the action.</li>
138	>	*
139	>	* <li> search: Return the first available non-null result of
140	>	* applying a given function on each element; skipping further
141	>	* search when a result is found.</li>
142	>	*
143	>	* <li> reduce: Accumulate each element.  The supplied reduction
144	>	* function cannot rely on ordering (more formally, it should be
145	>	* both associative and commutative).  There are five variants:
146	>	*
147	>	* <ul>
148	>	*
149	>	* <li> Plain reductions. (There is not a form of this method for
150	>	* (key, value) function arguments since there is no corresponding
151	>	* return type.)</li>
152	>	*
153	>	* <li> Mapped reductions that accumulate the results of a given
154	>	* function applied to each element.</li>
155	>	*
156	>	* <li> Reductions to scalar doubles, longs, and ints, using a
157	>	* given basis value.</li>
158	>	*
159	>	* </ul>
160	>	* </li>
161	>	* </ul>
162	>	*
163	>	* <p>These bulk operations accept a {@code parallelismThreshold}
164	>	* argument. Methods proceed sequentially if the current map size is
165	>	* estimated to be less than the given threshold. Using a value of
166	>	* {@code Long.MAX_VALUE} suppresses all parallelism.  Using a value
167	>	* of {@code 1} results in maximal parallelism by partitioning into
168	>	* enough subtasks to fully utilize the {@link
169	>	* ForkJoinPool#commonPool()} that is used for all parallel
170	>	* computations. Normally, you would initially choose one of these
171	>	* extreme values, and then measure performance of using in-between
172	>	* values that trade off overhead versus throughput.
173	>	*
174	>	* <p>The concurrency properties of bulk operations follow
175	>	* from those of ConcurrentHashMap: Any non-null result returned
176	>	* from {@code get(key)} and related access methods bears a
177	>	* happens-before relation with the associated insertion or
178	>	* update.  The result of any bulk operation reflects the
179	>	* composition of these per-element relations (but is not
180	>	* necessarily atomic with respect to the map as a whole unless it
181	>	* is somehow known to be quiescent).  Conversely, because keys
182	>	* and values in the map are never null, null serves as a reliable
183	>	* atomic indicator of the current lack of any result.  To
184	>	* maintain this property, null serves as an implicit basis for
185	>	* all non-scalar reduction operations. For the double, long, and
186	>	* int versions, the basis should be one that, when combined with
187	>	* any other value, returns that other value (more formally, it
188	>	* should be the identity element for the reduction). Most common
189	>	* reductions have these properties; for example, computing a sum
190	>	* with basis 0 or a minimum with basis MAX_VALUE.
191	>	*
192	>	* <p>Search and transformation functions provided as arguments
193	>	* should similarly return null to indicate the lack of any result
194	>	* (in which case it is not used). In the case of mapped
195	>	* reductions, this also enables transformations to serve as
196	>	* filters, returning null (or, in the case of primitive
197	>	* specializations, the identity basis) if the element should not
198	>	* be combined. You can create compound transformations and
199	>	* filterings by composing them yourself under this "null means
200	>	* there is nothing there now" rule before using them in search or
201	>	* reduce operations.
202	>	*
203	>	* <p>Methods accepting and/or returning Entry arguments maintain
204	>	* key-value associations. They may be useful for example when
205	>	* finding the key for the greatest value. Note that "plain" Entry
206	>	* arguments can be supplied using {@code new
207	>	* AbstractMap.SimpleEntry(k,v)}.
208	>	*
209	>	* <p>Bulk operations may complete abruptly, throwing an
210	>	* exception encountered in the application of a supplied
211	>	* function. Bear in mind when handling such exceptions that other
212	>	* concurrently executing functions could also have thrown
213	>	* exceptions, or would have done so if the first exception had
214	>	* not occurred.
215	>	*
216	>	* <p>Speedups for parallel compared to sequential forms are common
217	>	* but not guaranteed.  Parallel operations involving brief functions
218	>	* on small maps may execute more slowly than sequential forms if the
219	>	* underlying work to parallelize the computation is more expensive
220	>	* than the computation itself.  Similarly, parallelization may not
221	>	* lead to much actual parallelism if all processors are busy
222	>	* performing unrelated tasks.
223	>	*
224	>	* <p>All arguments to all task methods must be non-null.
225		*
226		* <p>This class is a member of the
227		* <a href="{@docRoot}/../technotes/guides/collections/index.html">
#	Line 70 | Line 232 | import java.io.ObjectOutputStream;
232		* @param <K> the type of keys maintained by this map
233		* @param <V> the type of mapped values
234		*/
235	<	public class ConcurrentHashMap<K, V> extends AbstractMap<K, V>
236	<	implements ConcurrentMap<K, V>, Serializable {
235	>	public class ConcurrentHashMap<K,V> extends AbstractMap<K,V>
236	>	implements ConcurrentMap<K,V>, Serializable {
237		private static final long serialVersionUID = 7249069246763182397L;
238
239		/*
240	<	* The basic strategy is to subdivide the table among Segments,
241	<	* each of which itself is a concurrently readable hash table.
240	>	* Overview:
241	>	*
242	>	* The primary design goal of this hash table is to maintain
243	>	* concurrent readability (typically method get(), but also
244	>	* iterators and related methods) while minimizing update
245	>	* contention. Secondary goals are to keep space consumption about
246	>	* the same or better than java.util.HashMap, and to support high
247	>	* initial insertion rates on an empty table by many threads.
248	>	*
249	>	* This map usually acts as a binned (bucketed) hash table.  Each
250	>	* key-value mapping is held in a Node.  Most nodes are instances
251	>	* of the basic Node class with hash, key, value, and next
252	>	* fields. However, various subclasses exist: TreeNodes are
253	>	* arranged in balanced trees, not lists.  TreeBins hold the roots
254	>	* of sets of TreeNodes. ForwardingNodes are placed at the heads
255	>	* of bins during resizing. ReservationNodes are used as
256	>	* placeholders while establishing values in computeIfAbsent and
257	>	* related methods.  The types TreeBin, ForwardingNode, and
258	>	* ReservationNode do not hold normal user keys, values, or
259	>	* hashes, and are readily distinguishable during search etc
260	>	* because they have negative hash fields and null key and value
261	>	* fields. (These special nodes are either uncommon or transient,
262	>	* so the impact of carrying around some unused fields is
263	>	* insignificant.)
264	>	*
265	>	* The table is lazily initialized to a power-of-two size upon the
266	>	* first insertion.  Each bin in the table normally contains a
267	>	* list of Nodes (most often, the list has only zero or one Node).
268	>	* Table accesses require volatile/atomic reads, writes, and
269	>	* CASes.  Because there is no other way to arrange this without
270	>	* adding further indirections, we use intrinsics
271	>	* (sun.misc.Unsafe) operations.
272	>	*
273	>	* We use the top (sign) bit of Node hash fields for control
274	>	* purposes -- it is available anyway because of addressing
275	>	* constraints.  Nodes with negative hash fields are specially
276	>	* handled or ignored in map methods.
277	>	*
278	>	* Insertion (via put or its variants) of the first node in an
279	>	* empty bin is performed by just CASing it to the bin.  This is
280	>	* by far the most common case for put operations under most
281	>	* key/hash distributions.  Other update operations (insert,
282	>	* delete, and replace) require locks.  We do not want to waste
283	>	* the space required to associate a distinct lock object with
284	>	* each bin, so instead use the first node of a bin list itself as
285	>	* a lock. Locking support for these locks relies on builtin
286	>	* "synchronized" monitors.
287	>	*
288	>	* Using the first node of a list as a lock does not by itself
289	>	* suffice though: When a node is locked, any update must first
290	>	* validate that it is still the first node after locking it, and
291	>	* retry if not. Because new nodes are always appended to lists,
292	>	* once a node is first in a bin, it remains first until deleted
293	>	* or the bin becomes invalidated (upon resizing).
294	>	*
295	>	* The main disadvantage of per-bin locks is that other update
296	>	* operations on other nodes in a bin list protected by the same
297	>	* lock can stall, for example when user equals() or mapping
298	>	* functions take a long time.  However, statistically, under
299	>	* random hash codes, this is not a common problem.  Ideally, the
300	>	* frequency of nodes in bins follows a Poisson distribution
301	>	* (http://en.wikipedia.org/wiki/Poisson_distribution) with a
302	>	* parameter of about 0.5 on average, given the resizing threshold
303	>	* of 0.75, although with a large variance because of resizing
304	>	* granularity. Ignoring variance, the expected occurrences of
305	>	* list size k are (exp(-0.5) * pow(0.5, k) / factorial(k)). The
306	>	* first values are:
307	>	*
308	>	* 0:    0.60653066
309	>	* 1:    0.30326533
310	>	* 2:    0.07581633
311	>	* 3:    0.01263606
312	>	* 4:    0.00157952
313	>	* 5:    0.00015795
314	>	* 6:    0.00001316
315	>	* 7:    0.00000094
316	>	* 8:    0.00000006
317	>	* more: less than 1 in ten million
318	>	*
319	>	* Lock contention probability for two threads accessing distinct
320	>	* elements is roughly 1 / (8 * #elements) under random hashes.
321	>	*
322	>	* Actual hash code distributions encountered in practice
323	>	* sometimes deviate significantly from uniform randomness.  This
324	>	* includes the case when N > (1<<30), so some keys MUST collide.
325	>	* Similarly for dumb or hostile usages in which multiple keys are
326	>	* designed to have identical hash codes or ones that differs only
327	>	* in masked-out high bits. So we use a secondary strategy that
328	>	* applies when the number of nodes in a bin exceeds a
329	>	* threshold. These TreeBins use a balanced tree to hold nodes (a
330	>	* specialized form of red-black trees), bounding search time to
331	>	* O(log N).  Each search step in a TreeBin is at least twice as
332	>	* slow as in a regular list, but given that N cannot exceed
333	>	* (1<<64) (before running out of addresses) this bounds search
334	>	* steps, lock hold times, etc, to reasonable constants (roughly
335	>	* 100 nodes inspected per operation worst case) so long as keys
336	>	* are Comparable (which is very common -- String, Long, etc).
337	>	* TreeBin nodes (TreeNodes) also maintain the same "next"
338	>	* traversal pointers as regular nodes, so can be traversed in
339	>	* iterators in the same way.
340	>	*
341	>	* The table is resized when occupancy exceeds a percentage
342	>	* threshold (nominally, 0.75, but see below).  Any thread
343	>	* noticing an overfull bin may assist in resizing after the
344	>	* initiating thread allocates and sets up the replacement array.
345	>	* However, rather than stalling, these other threads may proceed
346	>	* with insertions etc.  The use of TreeBins shields us from the
347	>	* worst case effects of overfilling while resizes are in
348	>	* progress.  Resizing proceeds by transferring bins, one by one,
349	>	* from the table to the next table. However, threads claim small
350	>	* blocks of indices to transfer (via field transferIndex) before
351	>	* doing so, reducing contention.  A generation stamp in field
352	>	* sizeCtl ensures that resizings do not overlap. Because we are
353	>	* using power-of-two expansion, the elements from each bin must
354	>	* either stay at same index, or move with a power of two
355	>	* offset. We eliminate unnecessary node creation by catching
356	>	* cases where old nodes can be reused because their next fields
357	>	* won't change.  On average, only about one-sixth of them need
358	>	* cloning when a table doubles. The nodes they replace will be
359	>	* garbage collectable as soon as they are no longer referenced by
360	>	* any reader thread that may be in the midst of concurrently
361	>	* traversing table.  Upon transfer, the old table bin contains
362	>	* only a special forwarding node (with hash field "MOVED") that
363	>	* contains the next table as its key. On encountering a
364	>	* forwarding node, access and update operations restart, using
365	>	* the new table.
366	>	*
367	>	* Each bin transfer requires its bin lock, which can stall
368	>	* waiting for locks while resizing. However, because other
369	>	* threads can join in and help resize rather than contend for
370	>	* locks, average aggregate waits become shorter as resizing
371	>	* progresses.  The transfer operation must also ensure that all
372	>	* accessible bins in both the old and new table are usable by any
373	>	* traversal.  This is arranged in part by proceeding from the
374	>	* last bin (table.length - 1) up towards the first.  Upon seeing
375	>	* a forwarding node, traversals (see class Traverser) arrange to
376	>	* move to the new table without revisiting nodes.  To ensure that
377	>	* no intervening nodes are skipped even when moved out of order,
378	>	* a stack (see class TableStack) is created on first encounter of
379	>	* a forwarding node during a traversal, to maintain its place if
380	>	* later processing the current table. The need for these
381	>	* save/restore mechanics is relatively rare, but when one
382	>	* forwarding node is encountered, typically many more will be.
383	>	* So Traversers use a simple caching scheme to avoid creating so
384	>	* many new TableStack nodes. (Thanks to Peter Levart for
385	>	* suggesting use of a stack here.)
386	>	*
387	>	* The traversal scheme also applies to partial traversals of
388	>	* ranges of bins (via an alternate Traverser constructor)
389	>	* to support partitioned aggregate operations.  Also, read-only
390	>	* operations give up if ever forwarded to a null table, which
391	>	* provides support for shutdown-style clearing, which is also not
392	>	* currently implemented.
393	>	*
394	>	* Lazy table initialization minimizes footprint until first use,
395	>	* and also avoids resizings when the first operation is from a
396	>	* putAll, constructor with map argument, or deserialization.
397	>	* These cases attempt to override the initial capacity settings,
398	>	* but harmlessly fail to take effect in cases of races.
399	>	*
400	>	* The element count is maintained using a specialization of
401	>	* LongAdder. We need to incorporate a specialization rather than
402	>	* just use a LongAdder in order to access implicit
403	>	* contention-sensing that leads to creation of multiple
404	>	* CounterCells.  The counter mechanics avoid contention on
405	>	* updates but can encounter cache thrashing if read too
406	>	* frequently during concurrent access. To avoid reading so often,
407	>	* resizing under contention is attempted only upon adding to a
408	>	* bin already holding two or more nodes. Under uniform hash
409	>	* distributions, the probability of this occurring at threshold
410	>	* is around 13%, meaning that only about 1 in 8 puts check
411	>	* threshold (and after resizing, many fewer do so).
412	>	*
413	>	* TreeBins use a special form of comparison for search and
414	>	* related operations (which is the main reason we cannot use
415	>	* existing collections such as TreeMaps). TreeBins contain
416	>	* Comparable elements, but may contain others, as well as
417	>	* elements that are Comparable but not necessarily Comparable for
418	>	* the same T, so we cannot invoke compareTo among them. To handle
419	>	* this, the tree is ordered primarily by hash value, then by
420	>	* Comparable.compareTo order if applicable.  On lookup at a node,
421	>	* if elements are not comparable or compare as 0 then both left
422	>	* and right children may need to be searched in the case of tied
423	>	* hash values. (This corresponds to the full list search that
424	>	* would be necessary if all elements were non-Comparable and had
425	>	* tied hashes.) On insertion, to keep a total ordering (or as
426	>	* close as is required here) across rebalancings, we compare
427	>	* classes and identityHashCodes as tie-breakers. The red-black
428	>	* balancing code is updated from pre-jdk-collections
429	>	* (http://gee.cs.oswego.edu/dl/classes/collections/RBCell.java)
430	>	* based in turn on Cormen, Leiserson, and Rivest "Introduction to
431	>	* Algorithms" (CLR).
432	>	*
433	>	* TreeBins also require an additional locking mechanism.  While
434	>	* list traversal is always possible by readers even during
435	>	* updates, tree traversal is not, mainly because of tree-rotations
436	>	* that may change the root node and/or its linkages.  TreeBins
437	>	* include a simple read-write lock mechanism parasitic on the
438	>	* main bin-synchronization strategy: Structural adjustments
439	>	* associated with an insertion or removal are already bin-locked
440	>	* (and so cannot conflict with other writers) but must wait for
441	>	* ongoing readers to finish. Since there can be only one such
442	>	* waiter, we use a simple scheme using a single "waiter" field to
443	>	* block writers.  However, readers need never block.  If the root
444	>	* lock is held, they proceed along the slow traversal path (via
445	>	* next-pointers) until the lock becomes available or the list is
446	>	* exhausted, whichever comes first. These cases are not fast, but
447	>	* maximize aggregate expected throughput.
448	>	*
449	>	* Maintaining API and serialization compatibility with previous
450	>	* versions of this class introduces several oddities. Mainly: We
451	>	* leave untouched but unused constructor arguments referring to
452	>	* concurrencyLevel. We accept a loadFactor constructor argument,
453	>	* but apply it only to initial table capacity (which is the only
454	>	* time that we can guarantee to honor it.) We also declare an
455	>	* unused "Segment" class that is instantiated in minimal form
456	>	* only when serializing.
457	>	*
458	>	* Also, solely for compatibility with previous versions of this
459	>	* class, it extends AbstractMap, even though all of its methods
460	>	* are overridden, so it is just useless baggage.
461	>	*
462	>	* This file is organized to make things a little easier to follow
463	>	* while reading than they might otherwise: First the main static
464	>	* declarations and utilities, then fields, then main public
465	>	* methods (with a few factorings of multiple public methods into
466	>	* internal ones), then sizing methods, trees, traversers, and
467	>	* bulk operations.
468		*/
469
470		/* ---------------- Constants -------------- */
471
472		/**
473	<	* The default initial capacity for this table,
474	<	* used when not otherwise specified in a constructor.
473	>	* The largest possible table capacity.  This value must be
474	>	* exactly 1<<30 to stay within Java array allocation and indexing
475	>	* bounds for power of two table sizes, and is further required
476	>	* because the top two bits of 32bit hash fields are used for
477	>	* control purposes.
478		*/
479	<	static final int DEFAULT_INITIAL_CAPACITY = 16;
479	>	private static final int MAXIMUM_CAPACITY = 1 << 30;
480
481		/**
482	<	* The default load factor for this table, used when not
483	<	* otherwise specified in a constructor.
482	>	* The default initial table capacity.  Must be a power of 2
483	>	* (i.e., at least 1) and at most MAXIMUM_CAPACITY.
484		*/
485	<	static final float DEFAULT_LOAD_FACTOR = 0.75f;
485	>	private static final int DEFAULT_CAPACITY = 16;
486
487		/**
488	<	* The default concurrency level for this table, used when not
489	<	* otherwise specified in a constructor.
488	>	* The largest possible (non-power of two) array size.
489	>	* Needed by toArray and related methods.
490		*/
491	<	static final int DEFAULT_CONCURRENCY_LEVEL = 16;
491	>	static final int MAX_ARRAY_SIZE = Integer.MAX_VALUE - 8;
492
493		/**
494	<	* The maximum capacity, used if a higher value is implicitly
495	<	* 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.
494	>	* The default concurrency level for this table. Unused but
495	>	* defined for compatibility with previous versions of this class.
496		*/
497	<	static final int MAXIMUM_CAPACITY = 1 << 30;
497	>	private static final int DEFAULT_CONCURRENCY_LEVEL = 16;
498
499		/**
500	<	* The maximum number of segments to allow; used to bound
501	<	* constructor arguments.
500	>	* The load factor for this table. Overrides of this value in
501	>	* constructors affect only the initial table capacity.  The
502	>	* actual floating point value isn't normally used -- it is
503	>	* simpler to use expressions such as {@code n - (n >>> 2)} for
504	>	* the associated resizing threshold.
505		*/
506	<	static final int MAX_SEGMENTS = 1 << 16; // slightly conservative
506	>	private static final float LOAD_FACTOR = 0.75f;
507
508		/**
509	<	* Number of unsynchronized retries in size and containsValue
510	<	* methods before resorting to locking. This is used to avoid
511	<	* unbounded retries if tables undergo continuous modification
512	<	* which would make it impossible to obtain an accurate result.
509	>	* The bin count threshold for using a tree rather than list for a
510	>	* bin.  Bins are converted to trees when adding an element to a
511	>	* bin with at least this many nodes. The value must be greater
512	>	* than 2, and should be at least 8 to mesh with assumptions in
513	>	* tree removal about conversion back to plain bins upon
514	>	* shrinkage.
515		*/
516	<	static final int RETRIES_BEFORE_LOCK = 2;
123	<
124	<	/* ---------------- Fields -------------- */
516	>	static final int TREEIFY_THRESHOLD = 8;
517
518		/**
519	<	* Mask value for indexing into segments. The upper bits of a
520	<	* key's hash code are used to choose the segment.
519	>	* The bin count threshold for untreeifying a (split) bin during a
520	>	* resize operation. Should be less than TREEIFY_THRESHOLD, and at
521	>	* most 6 to mesh with shrinkage detection under removal.
522		*/
523	<	final int segmentMask;
523	>	static final int UNTREEIFY_THRESHOLD = 6;
524
525		/**
526	<	* Shift value for indexing within segments.
526	>	* The smallest table capacity for which bins may be treeified.
527	>	* (Otherwise the table is resized if too many nodes in a bin.)
528	>	* The value should be at least 4 * TREEIFY_THRESHOLD to avoid
529	>	* conflicts between resizing and treeification thresholds.
530		*/
531	<	final int segmentShift;
531	>	static final int MIN_TREEIFY_CAPACITY = 64;
532
533		/**
534	<	* The segments, each of which is a specialized hash table
534	>	* Minimum number of rebinnings per transfer step. Ranges are
535	>	* subdivided to allow multiple resizer threads.  This value
536	>	* serves as a lower bound to avoid resizers encountering
537	>	* excessive memory contention.  The value should be at least
538	>	* DEFAULT_CAPACITY.
539		*/
540	<	final Segment<K,V>[] segments;
141	<
142	<	transient Set<K> keySet;
143	<	transient Set<Map.Entry<K,V>> entrySet;
144	<	transient Collection<V> values;
145	<
146	<	/* ---------------- Small Utilities -------------- */
540	>	private static final int MIN_TRANSFER_STRIDE = 16;
541
542		/**
543	<	* Applies a supplemental hash function to a given hashCode, which
544	<	* defends against poor quality hash functions.  This is critical
151	<	* because HashMap uses power-of two length hash tables, that
152	<	* otherwise encounter collisions for hashCodes that do not differ
153	<	* in lower bits.
543	>	* The number of bits used for generation stamp in sizeCtl.
544	>	* Must be at least 6 for 32bit arrays.
545		*/
546	<	static int hash(int h) {
156	<	// This function ensures that hashCodes that differ only by
157	<	// constant multiples at each bit position have a bounded
158	<	// number of collisions (approximately 8 at default load factor).
159	<	h ^= (h >>> 20) ^ (h >>> 12);
160	<	return h ^ (h >>> 7) ^ (h >>> 4);
161	<	}
546	>	private static int RESIZE_STAMP_BITS = 16;
547
548		/**
549	<	* Returns the segment that should be used for key with given hash
550	<	* @param hash the hash code for the key
166	<	* @return the segment
549	>	* The maximum number of threads that can help resize.
550	>	* Must fit in 32 - RESIZE_STAMP_BITS bits.
551		*/
552	<	final Segment<K,V> segmentFor(int hash) {
169	<	return segments[(hash >>> segmentShift) & segmentMask];
170	<	}
171	<
172	<	/* ---------------- Inner Classes -------------- */
552	>	private static final int MAX_RESIZERS = (1 << (32 - RESIZE_STAMP_BITS)) - 1;
553
554		/**
555	<	* ConcurrentHashMap list entry. Note that this is never exported
176	<	* out as a user-visible Map.Entry.
177	<	*
178	<	* Because the value field is volatile, not final, it is legal wrt
179	<	* the Java Memory Model for an unsynchronized reader to see null
180	<	* instead of initial value when read via a data race.  Although a
181	<	* reordering leading to this is not likely to ever actually
182	<	* 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.
555	>	* The bit shift for recording size stamp in sizeCtl.
556		*/
557	<	static final class HashEntry<K,V> {
187	<	final K key;
188	<	final int hash;
189	<	volatile V value;
190	<	final HashEntry<K,V> next;
557	>	private static final int RESIZE_STAMP_SHIFT = 32 - RESIZE_STAMP_BITS;
558
559	<	HashEntry(K key, int hash, HashEntry<K,V> next, V value) {
560	<	this.key = key;
561	<	this.hash = hash;
562	<	this.next = next;
563	<	this.value = value;
564	<	}
559	>	/*
560	>	* Encodings for Node hash fields. See above for explanation.
561	>	*/
562	>	static final int MOVED     = -1; // hash for forwarding nodes
563	>	static final int TREEBIN   = -2; // hash for roots of trees
564	>	static final int RESERVED  = -3; // hash for transient reservations
565	>	static final int HASH_BITS = 0x7fffffff; // usable bits of normal node hash
566	>
567	>	/** Number of CPUS, to place bounds on some sizings */
568	>	static final int NCPU = Runtime.getRuntime().availableProcessors();
569	>
570	>	/** For serialization compatibility. */
571	>	private static final ObjectStreamField[] serialPersistentFields = {
572	>	new ObjectStreamField("segments", Segment[].class),
573	>	new ObjectStreamField("segmentMask", Integer.TYPE),
574	>	new ObjectStreamField("segmentShift", Integer.TYPE)
575	>	};
576
577	<	@SuppressWarnings("unchecked")
200	<	static final <K,V> HashEntry<K,V>[] newArray(int i) {
201	<	return new HashEntry[i];
202	<	}
203	<	}
577	>	/* ---------------- Nodes -------------- */
578
579		/**
580	<	* Segments are specialized versions of hash tables.  This
581	<	* subclasses from ReentrantLock opportunistically, just to
582	<	* simplify some locking and avoid separate construction.
580	>	* Key-value entry.  This class is never exported out as a
581	>	* user-mutable Map.Entry (i.e., one supporting setValue; see
582	>	* MapEntry below), but can be used for read-only traversals used
583	>	* in bulk tasks.  Subclasses of Node with a negative hash field
584	>	* are special, and contain null keys and values (but are never
585	>	* exported).  Otherwise, keys and vals are never null.
586		*/
587	<	static final class Segment<K,V> extends ReentrantLock implements Serializable {
588	<	/*
589	<	* Segments maintain a table of entry lists that are ALWAYS
590	<	* kept in a consistent state, so can be read without locking.
591	<	* Next fields of nodes are immutable (final).  All list
215	<	* additions are performed at the front of each bin. This
216	<	* makes it easy to check changes, and also fast to traverse.
217	<	* When nodes would otherwise be changed, new nodes are
218	<	* created to replace them. This works well for hash tables
219	<	* since the bin lists tend to be short. (The average length
220	<	* is less than two for the default load factor threshold.)
221	<	*
222	<	* Read operations can thus proceed without locking, but rely
223	<	* on selected uses of volatiles to ensure that completed
224	<	* write operations performed by other threads are
225	<	* noticed. For most purposes, the "count" field, tracking the
226	<	* number of elements, serves as that volatile variable
227	<	* ensuring visibility.  This is convenient because this field
228	<	* needs to be read in many read operations anyway:
229	<	*
230	<	*   - All (unsynchronized) read operations must first read the
231	<	*     "count" field, and should not look at table entries if
232	<	*     it is 0.
233	<	*
234	<	*   - All (synchronized) write operations should write to
235	<	*     the "count" field after structurally changing any bin.
236	<	*     The operations must not take any action that could even
237	<	*     momentarily cause a concurrent read operation to see
238	<	*     inconsistent data. This is made easier by the nature of
239	<	*     the read operations in Map. For example, no operation
240	<	*     can reveal that the table has grown but the threshold
241	<	*     has not yet been updated, so there are no atomicity
242	<	*     requirements for this with respect to reads.
243	<	*
244	<	* As a guide, all critical volatile reads and writes to the
245	<	* count field are marked in code comments.
246	<	*/
247	<
248	<	private static final long serialVersionUID = 2249069246763182397L;
249	<
250	<	/**
251	<	* The number of elements in this segment's region.
252	<	*/
253	<	transient volatile int count;
254	<
255	<	/**
256	<	* Number of updates that alter the size of the table. This is
257	<	* used during bulk-read methods to make sure they see a
258	<	* consistent snapshot: If modCounts change during a traversal
259	<	* of segments computing size or checking containsValue, then
260	<	* we might have an inconsistent view of state so (usually)
261	<	* must retry.
262	<	*/
263	<	transient int modCount;
264	<
265	<	/**
266	<	* The table is rehashed when its size exceeds this threshold.
267	<	* (The value of this field is always <tt>(int)(capacity *
268	<	* loadFactor)</tt>.)
269	<	*/
270	<	transient int threshold;
271	<
272	<	/**
273	<	* The per-segment table.
274	<	*/
275	<	transient volatile HashEntry<K,V>[] table;
276	<
277	<	/**
278	<	* The load factor for the hash table.  Even though this value
279	<	* is same for all segments, it is replicated to avoid needing
280	<	* links to outer object.
281	<	* @serial
282	<	*/
283	<	final float loadFactor;
284	<
285	<	Segment(int initialCapacity, float lf) {
286	<	loadFactor = lf;
287	<	setTable(HashEntry.<K,V>newArray(initialCapacity));
288	<	}
289	<
290	<	@SuppressWarnings("unchecked")
291	<	static final <K,V> Segment<K,V>[] newArray(int i) {
292	<	return new Segment[i];
293	<	}
587	>	static class Node<K,V> implements Map.Entry<K,V> {
588	>	final int hash;
589	>	final K key;
590	>	volatile V val;
591	>	volatile Node<K,V> next;
592
593	<	/**
594	<	* Sets table to new HashEntry array.
595	<	* Call only while holding lock or in constructor.
596	<	*/
597	<	void setTable(HashEntry<K,V>[] newTable) {
300	<	threshold = (int)(newTable.length * loadFactor);
301	<	table = newTable;
593	>	Node(int hash, K key, V val, Node<K,V> next) {
594	>	this.hash = hash;
595	>	this.key = key;
596	>	this.val = val;
597	>	this.next = next;
598		}
599
600	<	/**
601	<	* Returns properly casted first entry of bin for given hash.
602	<	*/
603	<	HashEntry<K,V> getFirst(int hash) {
604	<	HashEntry<K,V>[] tab = table;
605	<	return tab[hash & (tab.length - 1)];
600	>	public final K getKey()     { return key; }
601	>	public final V getValue()   { return val; }
602	>	public final int hashCode() { return key.hashCode() ^ val.hashCode(); }
603	>	public final String toString() {
604	>	return Helpers.mapEntryToString(key, val);
605	>	}
606	>	public final V setValue(V value) {
607	>	throw new UnsupportedOperationException();
608	>	}
609	>
610	>	public final boolean equals(Object o) {
611	>	Object k, v, u; Map.Entry<?,?> e;
612	>	return ((o instanceof Map.Entry) &&
613	>	(k = (e = (Map.Entry<?,?>)o).getKey()) != null &&
614	>	(v = e.getValue()) != null &&
615	>	(k == key || k.equals(key)) &&
616	>	(v == (u = val) || v.equals(u)));
617		}
618
619		/**
620	<	* Reads value field of an entry under lock. Called if value
314	<	* field ever appears to be null. This is possible only if a
315	<	* compiler happens to reorder a HashEntry initialization with
316	<	* its table assignment, which is legal under memory model
317	<	* but is not known to ever occur.
620	>	* Virtualized support for map.get(); overridden in subclasses.
621		*/
622	<	V readValueUnderLock(HashEntry<K,V> e) {
623	<	lock();
624	<	try {
625	<	return e.value;
626	<	} finally {
627	<	unlock();
628	<	}
629	<	}
630	<
328	<	/* Specialized implementations of map methods */
329	<
330	<	V get(Object key, int hash) {
331	<	if (count != 0) { // read-volatile
332	<	HashEntry<K,V> e = getFirst(hash);
333	<	while (e != null) {
334	<	if (e.hash == hash && key.equals(e.key)) {
335	<	V v = e.value;
336	<	if (v != null)
337	<	return v;
338	<	return readValueUnderLock(e); // recheck
339	<	}
340	<	e = e.next;
341	<	}
622	>	Node<K,V> find(int h, Object k) {
623	>	Node<K,V> e = this;
624	>	if (k != null) {
625	>	do {
626	>	K ek;
627	>	if (e.hash == h &&
628	>	((ek = e.key) == k || (ek != null && k.equals(ek))))
629	>	return e;
630	>	} while ((e = e.next) != null);
631		}
632		return null;
633		}
634	+	}
635
636	<	boolean containsKey(Object key, int hash) {
347	<	if (count != 0) { // read-volatile
348	<	HashEntry<K,V> e = getFirst(hash);
349	<	while (e != null) {
350	<	if (e.hash == hash && key.equals(e.key))
351	<	return true;
352	<	e = e.next;
353	<	}
354	<	}
355	<	return false;
356	<	}
636	>	/* ---------------- Static utilities -------------- */
637
638	<	boolean containsValue(Object value) {
639	<	if (count != 0) { // read-volatile
640	<	HashEntry<K,V>[] tab = table;
641	<	int len = tab.length;
642	<	for (int i = 0 ; i < len; i++) {
643	<	for (HashEntry<K,V> e = tab[i]; e != null; e = e.next) {
644	<	V v = e.value;
645	<	if (v == null) // recheck
646	<	v = readValueUnderLock(e);
647	<	if (value.equals(v))
648	<	return true;
649	<	}
650	<	}
651	<	}
652	<	return false;
653	<	}
638	>	/**
639	>	* Spreads (XORs) higher bits of hash to lower and also forces top
640	>	* bit to 0. Because the table uses power-of-two masking, sets of
641	>	* hashes that vary only in bits above the current mask will
642	>	* always collide. (Among known examples are sets of Float keys
643	>	* holding consecutive whole numbers in small tables.)  So we
644	>	* apply a transform that spreads the impact of higher bits
645	>	* downward. There is a tradeoff between speed, utility, and
646	>	* quality of bit-spreading. Because many common sets of hashes
647	>	* are already reasonably distributed (so don't benefit from
648	>	* spreading), and because we use trees to handle large sets of
649	>	* collisions in bins, we just XOR some shifted bits in the
650	>	* cheapest possible way to reduce systematic lossage, as well as
651	>	* to incorporate impact of the highest bits that would otherwise
652	>	* never be used in index calculations because of table bounds.
653	>	*/
654	>	static final int spread(int h) {
655	>	return (h ^ (h >>> 16)) & HASH_BITS;
656	>	}
657
658	<	boolean replace(K key, int hash, V oldValue, V newValue) {
659	<	lock();
660	<	try {
661	<	HashEntry<K,V> e = getFirst(hash);
662	<	while (e != null && (e.hash != hash || !key.equals(e.key)))
663	<	e = e.next;
664	<
665	<	boolean replaced = false;
666	<	if (e != null && oldValue.equals(e.value)) {
667	<	replaced = true;
668	<	e.value = newValue;
669	<	}
670	<	return replaced;
388	<	} finally {
389	<	unlock();
390	<	}
391	<	}
658	>	/**
659	>	* Returns a power of two table size for the given desired capacity.
660	>	* See Hackers Delight, sec 3.2
661	>	*/
662	>	private static final int tableSizeFor(int c) {
663	>	int n = c - 1;
664	>	n |= n >>> 1;
665	>	n |= n >>> 2;
666	>	n |= n >>> 4;
667	>	n |= n >>> 8;
668	>	n |= n >>> 16;
669	>	return (n < 0) ? 1 : (n >= MAXIMUM_CAPACITY) ? MAXIMUM_CAPACITY : n + 1;
670	>	}
671
672	<	V replace(K key, int hash, V newValue) {
673	<	lock();
674	<	try {
675	<	HashEntry<K,V> e = getFirst(hash);
676	<	while (e != null && (e.hash != hash || !key.equals(e.key)))
677	<	e = e.next;
678	<
679	<	V oldValue = null;
680	<	if (e != null) {
681	<	oldValue = e.value;
682	<	e.value = newValue;
672	>	/**
673	>	* Returns x's Class if it is of the form "class C implements
674	>	* Comparable<C>", else null.
675	>	*/
676	>	static Class<?> comparableClassFor(Object x) {
677	>	if (x instanceof Comparable) {
678	>	Class<?> c; Type[] ts, as; Type t; ParameterizedType p;
679	>	if ((c = x.getClass()) == String.class) // bypass checks
680	>	return c;
681	>	if ((ts = c.getGenericInterfaces()) != null) {
682	>	for (int i = 0; i < ts.length; ++i) {
683	>	if (((t = ts[i]) instanceof ParameterizedType) &&
684	>	((p = (ParameterizedType)t).getRawType() ==
685	>	Comparable.class) &&
686	>	(as = p.getActualTypeArguments()) != null &&
687	>	as.length == 1 && as[0] == c) // type arg is c
688	>	return c;
689		}
405	–	return oldValue;
406	–	} finally {
407	–	unlock();
690		}
691		}
692	+	return null;
693	+	}
694
695	+	/**
696	+	* Returns k.compareTo(x) if x matches kc (k's screened comparable
697	+	* class), else 0.
698	+	*/
699	+	@SuppressWarnings({"rawtypes","unchecked"}) // for cast to Comparable
700	+	static int compareComparables(Class<?> kc, Object k, Object x) {
701	+	return (x == null || x.getClass() != kc ? 0 :
702	+	((Comparable)k).compareTo(x));
703	+	}
704
705	<	V put(K key, int hash, V value, boolean onlyIfAbsent) {
413	<	lock();
414	<	try {
415	<	int c = count;
416	<	if (c++ > threshold) // ensure capacity
417	<	rehash();
418	<	HashEntry<K,V>[] tab = table;
419	<	int index = hash & (tab.length - 1);
420	<	HashEntry<K,V> first = tab[index];
421	<	HashEntry<K,V> e = first;
422	<	while (e != null && (e.hash != hash || !key.equals(e.key)))
423	<	e = e.next;
424	<
425	<	V oldValue;
426	<	if (e != null) {
427	<	oldValue = e.value;
428	<	if (!onlyIfAbsent)
429	<	e.value = value;
430	<	}
431	<	else {
432	<	oldValue = null;
433	<	++modCount;
434	<	tab[index] = new HashEntry<K,V>(key, hash, first, value);
435	<	count = c; // write-volatile
436	<	}
437	<	return oldValue;
438	<	} finally {
439	<	unlock();
440	<	}
441	<	}
705	>	/* ---------------- Table element access -------------- */
706
707	<	void rehash() {
708	<	HashEntry<K,V>[] oldTable = table;
709	<	int oldCapacity = oldTable.length;
710	<	if (oldCapacity >= MAXIMUM_CAPACITY)
711	<	return;
707	>	/*
708	>	* Volatile access methods are used for table elements as well as
709	>	* elements of in-progress next table while resizing.  All uses of
710	>	* the tab arguments must be null checked by callers.  All callers
711	>	* also paranoically precheck that tab's length is not zero (or an
712	>	* equivalent check), thus ensuring that any index argument taking
713	>	* the form of a hash value anded with (length - 1) is a valid
714	>	* index.  Note that, to be correct wrt arbitrary concurrency
715	>	* errors by users, these checks must operate on local variables,
716	>	* which accounts for some odd-looking inline assignments below.
717	>	* Note that calls to setTabAt always occur within locked regions,
718	>	* and so in principle require only release ordering, not
719	>	* full volatile semantics, but are currently coded as volatile
720	>	* writes to be conservative.
721	>	*/
722	>
723	>	@SuppressWarnings("unchecked")
724	>	static final <K,V> Node<K,V> tabAt(Node<K,V>[] tab, int i) {
725	>	return (Node<K,V>)U.getObjectVolatile(tab, ((long)i << ASHIFT) + ABASE);
726	>	}
727
728	<	/*
729	<	* Reclassify nodes in each list to new Map.  Because we are
730	<	* using power-of-two expansion, the elements from each bin
731	<	* must either stay at same index, or move with a power of two
453	<	* offset. We eliminate unnecessary node creation by catching
454	<	* cases where old nodes can be reused because their next
455	<	* fields won't change. Statistically, at the default
456	<	* threshold, only about one-sixth of them need cloning when
457	<	* a table doubles. The nodes they replace will be garbage
458	<	* collectable as soon as they are no longer referenced by any
459	<	* 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;
728	>	static final <K,V> boolean casTabAt(Node<K,V>[] tab, int i,
729	>	Node<K,V> c, Node<K,V> v) {
730	>	return U.compareAndSwapObject(tab, ((long)i << ASHIFT) + ABASE, c, v);
731	>	}
732
733	<	else {
734	<	// Reuse trailing consecutive sequence at same slot
735	<	HashEntry<K,V> lastRun = e;
482	<	int lastIdx = idx;
483	<	for (HashEntry<K,V> last = next;
484	<	last != null;
485	<	last = last.next) {
486	<	int k = last.hash & sizeMask;
487	<	if (k != lastIdx) {
488	<	lastIdx = k;
489	<	lastRun = last;
490	<	}
491	<	}
492	<	newTable[lastIdx] = lastRun;
733	>	static final <K,V> void setTabAt(Node<K,V>[] tab, int i, Node<K,V> v) {
734	>	U.putObjectVolatile(tab, ((long)i << ASHIFT) + ABASE, v);
735	>	}
736
737	<	// Clone all remaining nodes
495	<	for (HashEntry<K,V> p = e; p != lastRun; p = p.next) {
496	<	int k = p.hash & sizeMask;
497	<	HashEntry<K,V> n = newTable[k];
498	<	newTable[k] = new HashEntry<K,V>(p.key, p.hash,
499	<	n, p.value);
500	<	}
501	<	}
502	<	}
503	<	}
504	<	table = newTable;
505	<	}
737	>	/* ---------------- Fields -------------- */
738
739	<	/**
740	<	* Remove; match on key only if value null, else match both.
741	<	*/
742	<	V remove(Object key, int hash, Object value) {
743	<	lock();
512	<	try {
513	<	int c = count - 1;
514	<	HashEntry<K,V>[] tab = table;
515	<	int index = hash & (tab.length - 1);
516	<	HashEntry<K,V> first = tab[index];
517	<	HashEntry<K,V> e = first;
518	<	while (e != null && (e.hash != hash || !key.equals(e.key)))
519	<	e = e.next;
520	<
521	<	V oldValue = null;
522	<	if (e != null) {
523	<	V v = e.value;
524	<	if (value == null || value.equals(v)) {
525	<	oldValue = v;
526	<	// All entries following removed node can stay
527	<	// in list, but all preceding ones need to be
528	<	// cloned.
529	<	++modCount;
530	<	HashEntry<K,V> newFirst = e.next;
531	<	for (HashEntry<K,V> p = first; p != e; p = p.next)
532	<	newFirst = new HashEntry<K,V>(p.key, p.hash,
533	<	newFirst, p.value);
534	<	tab[index] = newFirst;
535	<	count = c; // write-volatile
536	<	}
537	<	}
538	<	return oldValue;
539	<	} finally {
540	<	unlock();
541	<	}
542	<	}
739	>	/**
740	>	* The array of bins. Lazily initialized upon first insertion.
741	>	* Size is always a power of two. Accessed directly by iterators.
742	>	*/
743	>	transient volatile Node<K,V>[] table;
744
745	<	void clear() {
746	<	if (count != 0) {
747	<	lock();
748	<	try {
548	<	HashEntry<K,V>[] tab = table;
549	<	for (int i = 0; i < tab.length ; i++)
550	<	tab[i] = null;
551	<	++modCount;
552	<	count = 0; // write-volatile
553	<	} finally {
554	<	unlock();
555	<	}
556	<	}
557	<	}
558	<	}
745	>	/**
746	>	* The next table to use; non-null only while resizing.
747	>	*/
748	>	private transient volatile Node<K,V>[] nextTable;
749
750	+	/**
751	+	* Base counter value, used mainly when there is no contention,
752	+	* but also as a fallback during table initialization
753	+	* races. Updated via CAS.
754	+	*/
755	+	private transient volatile long baseCount;
756
757	+	/**
758	+	* Table initialization and resizing control.  When negative, the
759	+	* table is being initialized or resized: -1 for initialization,
760	+	* else -(1 + the number of active resizing threads).  Otherwise,
761	+	* when table is null, holds the initial table size to use upon
762	+	* creation, or 0 for default. After initialization, holds the
763	+	* next element count value upon which to resize the table.
764	+	*/
765	+	private transient volatile int sizeCtl;
766
767	<	/* ---------------- Public operations -------------- */
767	>	/**
768	>	* The next table index (plus one) to split while resizing.
769	>	*/
770	>	private transient volatile int transferIndex;
771
772		/**
773	<	* Creates a new, empty map with the specified initial
566	<	* capacity, load factor and concurrency level.
567	<	*
568	<	* @param initialCapacity the initial capacity. The implementation
569	<	* performs internal sizing to accommodate this many elements.
570	<	* @param loadFactor  the load factor threshold, used to control resizing.
571	<	* Resizing may be performed when the average number of elements per
572	<	* bin exceeds this threshold.
573	<	* @param concurrencyLevel the estimated number of concurrently
574	<	* updating threads. The implementation performs internal sizing
575	<	* to try to accommodate this many threads.
576	<	* @throws IllegalArgumentException if the initial capacity is
577	<	* negative or the load factor or concurrencyLevel are
578	<	* nonpositive.
773	>	* Spinlock (locked via CAS) used when resizing and/or creating CounterCells.
774		*/
775	<	public ConcurrentHashMap(int initialCapacity,
581	<	float loadFactor, int concurrencyLevel) {
582	<	if (!(loadFactor > 0) || initialCapacity < 0 || concurrencyLevel <= 0)
583	<	throw new IllegalArgumentException();
775	>	private transient volatile int cellsBusy;
776
777	<	if (concurrencyLevel > MAX_SEGMENTS)
778	<	concurrencyLevel = MAX_SEGMENTS;
777	>	/**
778	>	* Table of counter cells. When non-null, size is a power of 2.
779	>	*/
780	>	private transient volatile CounterCell[] counterCells;
781
782	<	// Find power-of-two sizes best matching arguments
783	<	int sshift = 0;
784	<	int ssize = 1;
785	<	while (ssize < concurrencyLevel) {
592	<	++sshift;
593	<	ssize <<= 1;
594	<	}
595	<	segmentShift = 32 - sshift;
596	<	segmentMask = ssize - 1;
597	<	this.segments = Segment.newArray(ssize);
598	<
599	<	if (initialCapacity > MAXIMUM_CAPACITY)
600	<	initialCapacity = MAXIMUM_CAPACITY;
601	<	int c = initialCapacity / ssize;
602	<	if (c * ssize < initialCapacity)
603	<	++c;
604	<	int cap = 1;
605	<	while (cap < c)
606	<	cap <<= 1;
782	>	// views
783	>	private transient KeySetView<K,V> keySet;
784	>	private transient ValuesView<K,V> values;
785	>	private transient EntrySetView<K,V> entrySet;
786
787	<	for (int i = 0; i < this.segments.length; ++i)
788	<	this.segments[i] = new Segment<K,V>(cap, loadFactor);
610	<	}
787	>
788	>	/* ---------------- Public operations -------------- */
789
790		/**
791	<	* Creates a new, empty map with the specified initial capacity
614	<	* and load factor and with the default concurrencyLevel (16).
615	<	*
616	<	* @param initialCapacity The implementation performs internal
617	<	* sizing to accommodate this many elements.
618	<	* @param loadFactor  the load factor threshold, used to control resizing.
619	<	* Resizing may be performed when the average number of elements per
620	<	* bin exceeds this threshold.
621	<	* @throws IllegalArgumentException if the initial capacity of
622	<	* elements is negative or the load factor is nonpositive
623	<	*
624	<	* @since 1.6
791	>	* Creates a new, empty map with the default initial table size (16).
792		*/
793	<	public ConcurrentHashMap(int initialCapacity, float loadFactor) {
627	<	this(initialCapacity, loadFactor, DEFAULT_CONCURRENCY_LEVEL);
793	>	public ConcurrentHashMap() {
794		}
795
796		/**
797	<	* Creates a new, empty map with the specified initial capacity,
798	<	* and with default load factor (0.75) and concurrencyLevel (16).
797	>	* Creates a new, empty map with an initial table size
798	>	* accommodating the specified number of elements without the need
799	>	* to dynamically resize.
800		*
801	<	* @param initialCapacity the initial capacity. The implementation
802	<	* performs internal sizing to accommodate this many elements.
801	>	* @param initialCapacity The implementation performs internal
802	>	* sizing to accommodate this many elements.
803		* @throws IllegalArgumentException if the initial capacity of
804	<	* elements is negative.
804	>	* elements is negative
805		*/
806		public ConcurrentHashMap(int initialCapacity) {
807	<	this(initialCapacity, DEFAULT_LOAD_FACTOR, DEFAULT_CONCURRENCY_LEVEL);
808	<	}
809	<
810	<	/**
811	<	* Creates a new, empty map with a default initial capacity (16),
812	<	* load factor (0.75) and concurrencyLevel (16).
646	<	*/
647	<	public ConcurrentHashMap() {
648	<	this(DEFAULT_INITIAL_CAPACITY, DEFAULT_LOAD_FACTOR, DEFAULT_CONCURRENCY_LEVEL);
807	>	if (initialCapacity < 0)
808	>	throw new IllegalArgumentException();
809	>	int cap = ((initialCapacity >= (MAXIMUM_CAPACITY >>> 1)) ?
810	>	MAXIMUM_CAPACITY :
811	>	tableSizeFor(initialCapacity + (initialCapacity >>> 1) + 1));
812	>	this.sizeCtl = cap;
813		}
814
815		/**
816		* Creates a new map with the same mappings as the given map.
653	–	* The map is created with a capacity of 1.5 times the number
654	–	* of mappings in the given map or 16 (whichever is greater),
655	–	* and a default load factor (0.75) and concurrencyLevel (16).
817		*
818		* @param m the map
819		*/
820		public ConcurrentHashMap(Map<? extends K, ? extends V> m) {
821	<	this(Math.max((int) (m.size() / DEFAULT_LOAD_FACTOR) + 1,
661	<	DEFAULT_INITIAL_CAPACITY),
662	<	DEFAULT_LOAD_FACTOR, DEFAULT_CONCURRENCY_LEVEL);
821	>	this.sizeCtl = DEFAULT_CAPACITY;
822		putAll(m);
823		}
824
825		/**
826	<	* Returns <tt>true</tt> if this map contains no key-value mappings.
826	>	* Creates a new, empty map with an initial table size based on
827	>	* the given number of elements ({@code initialCapacity}) and
828	>	* initial table density ({@code loadFactor}).
829	>	*
830	>	* @param initialCapacity the initial capacity. The implementation
831	>	* performs internal sizing to accommodate this many elements,
832	>	* given the specified load factor.
833	>	* @param loadFactor the load factor (table density) for
834	>	* establishing the initial table size
835	>	* @throws IllegalArgumentException if the initial capacity of
836	>	* elements is negative or the load factor is nonpositive
837		*
838	<	* @return <tt>true</tt> if this map contains no key-value mappings
838	>	* @since 1.6
839		*/
840	<	public boolean isEmpty() {
841	<	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;
840	>	public ConcurrentHashMap(int initialCapacity, float loadFactor) {
841	>	this(initialCapacity, loadFactor, 1);
842		}
843
844		/**
845	<	* Returns the number of key-value mappings in this map.  If the
846	<	* map contains more than <tt>Integer.MAX_VALUE</tt> elements, returns
847	<	* <tt>Integer.MAX_VALUE</tt>.
845	>	* Creates a new, empty map with an initial table size based on
846	>	* the given number of elements ({@code initialCapacity}), table
847	>	* density ({@code loadFactor}), and number of concurrently
848	>	* updating threads ({@code concurrencyLevel}).
849		*
850	<	* @return the number of key-value mappings in this map
850	>	* @param initialCapacity the initial capacity. The implementation
851	>	* performs internal sizing to accommodate this many elements,
852	>	* given the specified load factor.
853	>	* @param loadFactor the load factor (table density) for
854	>	* establishing the initial table size
855	>	* @param concurrencyLevel the estimated number of concurrently
856	>	* updating threads. The implementation may use this value as
857	>	* a sizing hint.
858	>	* @throws IllegalArgumentException if the initial capacity is
859	>	* negative or the load factor or concurrencyLevel are
860	>	* nonpositive
861	>	*/
862	>	public ConcurrentHashMap(int initialCapacity,
863	>	float loadFactor, int concurrencyLevel) {
864	>	if (!(loadFactor > 0.0f) || initialCapacity < 0 || concurrencyLevel <= 0)
865	>	throw new IllegalArgumentException();
866	>	if (initialCapacity < concurrencyLevel)   // Use at least as many bins
867	>	initialCapacity = concurrencyLevel;   // as estimated threads
868	>	long size = (long)(1.0 + (long)initialCapacity / loadFactor);
869	>	int cap = (size >= (long)MAXIMUM_CAPACITY) ?
870	>	MAXIMUM_CAPACITY : tableSizeFor((int)size);
871	>	this.sizeCtl = cap;
872	>	}
873	>
874	>	// Original (since JDK1.2) Map methods
875	>
876	>	/**
877	>	* {@inheritDoc}
878		*/
879		public int size() {
880	<	final Segment<K,V>[] segments = this.segments;
881	<	long sum = 0;
882	<	long check = 0;
883	<	int[] mc = new int[segments.length];
884	<	// Try a few times to get accurate count. On failure due to
885	<	// continuous async changes in table, resort to locking.
886	<	for (int k = 0; k < RETRIES_BEFORE_LOCK; ++k) {
887	<	check = 0;
888	<	sum = 0;
889	<	int mcsum = 0;
890	<	for (int i = 0; i < segments.length; ++i) {
722	<	sum += segments[i].count;
723	<	mcsum += mc[i] = segments[i].modCount;
724	<	}
725	<	if (mcsum != 0) {
726	<	for (int i = 0; i < segments.length; ++i) {
727	<	check += segments[i].count;
728	<	if (mc[i] != segments[i].modCount) {
729	<	check = -1; // force retry
730	<	break;
731	<	}
732	<	}
733	<	}
734	<	if (check == sum)
735	<	break;
736	<	}
737	<	if (check != sum) { // Resort to locking all segments
738	<	sum = 0;
739	<	for (int i = 0; i < segments.length; ++i)
740	<	segments[i].lock();
741	<	for (int i = 0; i < segments.length; ++i)
742	<	sum += segments[i].count;
743	<	for (int i = 0; i < segments.length; ++i)
744	<	segments[i].unlock();
745	<	}
746	<	if (sum > Integer.MAX_VALUE)
747	<	return Integer.MAX_VALUE;
748	<	else
749	<	return (int)sum;
880	>	long n = sumCount();
881	>	return ((n < 0L) ? 0 :
882	>	(n > (long)Integer.MAX_VALUE) ? Integer.MAX_VALUE :
883	>	(int)n);
884	>	}
885	>
886	>	/**
887	>	* {@inheritDoc}
888	>	*/
889	>	public boolean isEmpty() {
890	>	return sumCount() <= 0L; // ignore transient negative values
891		}
892
893		/**
#	Line 761 | Line 902 | public class ConcurrentHashMap<K, V> ext
902		* @throws NullPointerException if the specified key is null
903		*/
904		public V get(Object key) {
905	<	int hash = hash(key.hashCode());
906	<	return segmentFor(hash).get(key, hash);
905	>	Node<K,V>[] tab; Node<K,V> e, p; int n, eh; K ek;
906	>	int h = spread(key.hashCode());
907	>	if ((tab = table) != null && (n = tab.length) > 0 &&
908	>	(e = tabAt(tab, (n - 1) & h)) != null) {
909	>	if ((eh = e.hash) == h) {
910	>	if ((ek = e.key) == key || (ek != null && key.equals(ek)))
911	>	return e.val;
912	>	}
913	>	else if (eh < 0)
914	>	return (p = e.find(h, key)) != null ? p.val : null;
915	>	while ((e = e.next) != null) {
916	>	if (e.hash == h &&
917	>	((ek = e.key) == key || (ek != null && key.equals(ek))))
918	>	return e.val;
919	>	}
920	>	}
921	>	return null;
922		}
923
924		/**
925		* Tests if the specified object is a key in this table.
926		*
927	<	* @param  key   possible key
928	<	* @return <tt>true</tt> if and only if the specified object
927	>	* @param  key possible key
928	>	* @return {@code true} if and only if the specified object
929		*         is a key in this table, as determined by the
930	<	*         <tt>equals</tt> method; <tt>false</tt> otherwise.
930	>	*         {@code equals} method; {@code false} otherwise
931		* @throws NullPointerException if the specified key is null
932		*/
933		public boolean containsKey(Object key) {
934	<	int hash = hash(key.hashCode());
779	<	return segmentFor(hash).containsKey(key, hash);
934	>	return get(key) != null;
935		}
936
937		/**
938	<	* Returns <tt>true</tt> if this map maps one or more keys to the
939	<	* specified value. Note: This method requires a full internal
940	<	* traversal of the hash table, and so is much slower than
786	<	* method <tt>containsKey</tt>.
938	>	* Returns {@code true} if this map maps one or more keys to the
939	>	* specified value. Note: This method may require a full traversal
940	>	* of the map, and is much slower than method {@code containsKey}.
941		*
942		* @param value value whose presence in this map is to be tested
943	<	* @return <tt>true</tt> if this map maps one or more keys to the
943	>	* @return {@code true} if this map maps one or more keys to the
944		*         specified value
945		* @throws NullPointerException if the specified value is null
946		*/
947		public boolean containsValue(Object value) {
948		if (value == null)
949		throw new NullPointerException();
950	<
951	<	// See explanation of modCount use above
952	<
953	<	final Segment<K,V>[] segments = this.segments;
954	<	int[] mc = new int[segments.length];
955	<
802	<	// Try a few times without locking
803	<	for (int k = 0; k < RETRIES_BEFORE_LOCK; ++k) {
804	<	int sum = 0;
805	<	int mcsum = 0;
806	<	for (int i = 0; i < segments.length; ++i) {
807	<	int c = segments[i].count;
808	<	mcsum += mc[i] = segments[i].modCount;
809	<	if (segments[i].containsValue(value))
950	>	Node<K,V>[] t;
951	>	if ((t = table) != null) {
952	>	Traverser<K,V> it = new Traverser<K,V>(t, t.length, 0, t.length);
953	>	for (Node<K,V> p; (p = it.advance()) != null; ) {
954	>	V v;
955	>	if ((v = p.val) == value || (v != null && value.equals(v)))
956		return true;
957		}
812	–	boolean cleanSweep = true;
813	–	if (mcsum != 0) {
814	–	for (int i = 0; i < segments.length; ++i) {
815	–	int c = segments[i].count;
816	–	if (mc[i] != segments[i].modCount) {
817	–	cleanSweep = false;
818	–	break;
819	–	}
820	–	}
821	–	}
822	–	if (cleanSweep)
823	–	return false;
958		}
959	<	// Resort to locking all segments
826	<	for (int i = 0; i < segments.length; ++i)
827	<	segments[i].lock();
828	<	boolean found = false;
829	<	try {
830	<	for (int i = 0; i < segments.length; ++i) {
831	<	if (segments[i].containsValue(value)) {
832	<	found = true;
833	<	break;
834	<	}
835	<	}
836	<	} finally {
837	<	for (int i = 0; i < segments.length; ++i)
838	<	segments[i].unlock();
839	<	}
840	<	return found;
841	<	}
842	<
843	<	/**
844	<	* Legacy method testing if some key maps into the specified value
845	<	* in this table.  This method is identical in functionality to
846	<	* {@link #containsValue}, and exists solely to ensure
847	<	* full compatibility with class {@link java.util.Hashtable},
848	<	* which supported this method prior to introduction of the
849	<	* Java Collections framework.
850	<
851	<	* @param  value a value to search for
852	<	* @return <tt>true</tt> if and only if some key maps to the
853	<	*         <tt>value</tt> argument in this table as
854	<	*         determined by the <tt>equals</tt> method;
855	<	*         <tt>false</tt> otherwise
856	<	* @throws NullPointerException if the specified value is null
857	<	*/
858	<	public boolean contains(Object value) {
859	<	return containsValue(value);
959	>	return false;
960		}
961
962		/**
963		* Maps the specified key to the specified value in this table.
964		* Neither the key nor the value can be null.
965		*
966	<	* <p> The value can be retrieved by calling the <tt>get</tt> method
966	>	* <p>The value can be retrieved by calling the {@code get} method
967		* with a key that is equal to the original key.
968		*
969		* @param key key with which the specified value is to be associated
970		* @param value value to be associated with the specified key
971	<	* @return the previous value associated with <tt>key</tt>, or
972	<	*         <tt>null</tt> if there was no mapping for <tt>key</tt>
971	>	* @return the previous value associated with {@code key}, or
972	>	*         {@code null} if there was no mapping for {@code key}
973		* @throws NullPointerException if the specified key or value is null
974		*/
975		public V put(K key, V value) {
976	<	if (value == null)
877	<	throw new NullPointerException();
878	<	int hash = hash(key.hashCode());
879	<	return segmentFor(hash).put(key, hash, value, false);
976	>	return putVal(key, value, false);
977		}
978
979	<	/**
980	<	* {@inheritDoc}
981	<	*
982	<	* @return the previous value associated with the specified key,
983	<	*         or <tt>null</tt> if there was no mapping for the key
984	<	* @throws NullPointerException if the specified key or value is null
985	<	*/
986	<	public V putIfAbsent(K key, V value) {
987	<	if (value == null)
988	<	throw new NullPointerException();
989	<	int hash = hash(key.hashCode());
990	<	return segmentFor(hash).put(key, hash, value, true);
979	>	/** Implementation for put and putIfAbsent */
980	>	final V putVal(K key, V value, boolean onlyIfAbsent) {
981	>	if (key == null || value == null) throw new NullPointerException();
982	>	int hash = spread(key.hashCode());
983	>	int binCount = 0;
984	>	for (Node<K,V>[] tab = table;;) {
985	>	Node<K,V> f; int n, i, fh;
986	>	if (tab == null || (n = tab.length) == 0)
987	>	tab = initTable();
988	>	else if ((f = tabAt(tab, i = (n - 1) & hash)) == null) {
989	>	if (casTabAt(tab, i, null,
990	>	new Node<K,V>(hash, key, value, null)))
991	>	break;                   // no lock when adding to empty bin
992	>	}
993	>	else if ((fh = f.hash) == MOVED)
994	>	tab = helpTransfer(tab, f);
995	>	else {
996	>	V oldVal = null;
997	>	synchronized (f) {
998	>	if (tabAt(tab, i) == f) {
999	>	if (fh >= 0) {
1000	>	binCount = 1;
1001	>	for (Node<K,V> e = f;; ++binCount) {
1002	>	K ek;
1003	>	if (e.hash == hash &&
1004	>	((ek = e.key) == key ||
1005	>	(ek != null && key.equals(ek)))) {
1006	>	oldVal = e.val;
1007	>	if (!onlyIfAbsent)
1008	>	e.val = value;
1009	>	break;
1010	>	}
1011	>	Node<K,V> pred = e;
1012	>	if ((e = e.next) == null) {
1013	>	pred.next = new Node<K,V>(hash, key,
1014	>	value, null);
1015	>	break;
1016	>	}
1017	>	}
1018	>	}
1019	>	else if (f instanceof TreeBin) {
1020	>	Node<K,V> p;
1021	>	binCount = 2;
1022	>	if ((p = ((TreeBin<K,V>)f).putTreeVal(hash, key,
1023	>	value)) != null) {
1024	>	oldVal = p.val;
1025	>	if (!onlyIfAbsent)
1026	>	p.val = value;
1027	>	}
1028	>	}
1029	>	else if (f instanceof ReservationNode)
1030	>	throw new IllegalStateException("Recursive update");
1031	>	}
1032	>	}
1033	>	if (binCount != 0) {
1034	>	if (binCount >= TREEIFY_THRESHOLD)
1035	>	treeifyBin(tab, i);
1036	>	if (oldVal != null)
1037	>	return oldVal;
1038	>	break;
1039	>	}
1040	>	}
1041	>	}
1042	>	addCount(1L, binCount);
1043	>	return null;
1044		}
1045
1046		/**
#	Line 901 | Line 1051 | public class ConcurrentHashMap<K, V> ext
1051		* @param m mappings to be stored in this map
1052		*/
1053		public void putAll(Map<? extends K, ? extends V> m) {
1054	+	tryPresize(m.size());
1055		for (Map.Entry<? extends K, ? extends V> e : m.entrySet())
1056	<	put(e.getKey(), e.getValue());
1056	>	putVal(e.getKey(), e.getValue(), false);
1057		}
1058
1059		/**
#	Line 910 | Line 1061 | public class ConcurrentHashMap<K, V> ext
1061		* This method does nothing if the key is not in the map.
1062		*
1063		* @param  key the key that needs to be removed
1064	<	* @return the previous value associated with <tt>key</tt>, or
1065	<	*         <tt>null</tt> if there was no mapping for <tt>key</tt>
1064	>	* @return the previous value associated with {@code key}, or
1065	>	*         {@code null} if there was no mapping for {@code key}
1066		* @throws NullPointerException if the specified key is null
1067		*/
1068		public V remove(Object key) {
1069	<	int hash = hash(key.hashCode());
1070	<	return segmentFor(hash).remove(key, hash, null);
1069	>	return replaceNode(key, null, null);
1070	>	}
1071	>
1072	>	/**
1073	>	* Implementation for the four public remove/replace methods:
1074	>	* Replaces node value with v, conditional upon match of cv if
1075	>	* non-null.  If resulting value is null, delete.
1076	>	*/
1077	>	final V replaceNode(Object key, V value, Object cv) {
1078	>	int hash = spread(key.hashCode());
1079	>	for (Node<K,V>[] tab = table;;) {
1080	>	Node<K,V> f; int n, i, fh;
1081	>	if (tab == null || (n = tab.length) == 0 ||
1082	>	(f = tabAt(tab, i = (n - 1) & hash)) == null)
1083	>	break;
1084	>	else if ((fh = f.hash) == MOVED)
1085	>	tab = helpTransfer(tab, f);
1086	>	else {
1087	>	V oldVal = null;
1088	>	boolean validated = false;
1089	>	synchronized (f) {
1090	>	if (tabAt(tab, i) == f) {
1091	>	if (fh >= 0) {
1092	>	validated = true;
1093	>	for (Node<K,V> e = f, pred = null;;) {
1094	>	K ek;
1095	>	if (e.hash == hash &&
1096	>	((ek = e.key) == key ||
1097	>	(ek != null && key.equals(ek)))) {
1098	>	V ev = e.val;
1099	>	if (cv == null || cv == ev ||
1100	>	(ev != null && cv.equals(ev))) {
1101	>	oldVal = ev;
1102	>	if (value != null)
1103	>	e.val = value;
1104	>	else if (pred != null)
1105	>	pred.next = e.next;
1106	>	else
1107	>	setTabAt(tab, i, e.next);
1108	>	}
1109	>	break;
1110	>	}
1111	>	pred = e;
1112	>	if ((e = e.next) == null)
1113	>	break;
1114	>	}
1115	>	}
1116	>	else if (f instanceof TreeBin) {
1117	>	validated = true;
1118	>	TreeBin<K,V> t = (TreeBin<K,V>)f;
1119	>	TreeNode<K,V> r, p;
1120	>	if ((r = t.root) != null &&
1121	>	(p = r.findTreeNode(hash, key, null)) != null) {
1122	>	V pv = p.val;
1123	>	if (cv == null || cv == pv ||
1124	>	(pv != null && cv.equals(pv))) {
1125	>	oldVal = pv;
1126	>	if (value != null)
1127	>	p.val = value;
1128	>	else if (t.removeTreeNode(p))
1129	>	setTabAt(tab, i, untreeify(t.first));
1130	>	}
1131	>	}
1132	>	}
1133	>	else if (f instanceof ReservationNode)
1134	>	throw new IllegalStateException("Recursive update");
1135	>	}
1136	>	}
1137	>	if (validated) {
1138	>	if (oldVal != null) {
1139	>	if (value == null)
1140	>	addCount(-1L, -1);
1141	>	return oldVal;
1142	>	}
1143	>	break;
1144	>	}
1145	>	}
1146	>	}
1147	>	return null;
1148	>	}
1149	>
1150	>	/**
1151	>	* Removes all of the mappings from this map.
1152	>	*/
1153	>	public void clear() {
1154	>	long delta = 0L; // negative number of deletions
1155	>	int i = 0;
1156	>	Node<K,V>[] tab = table;
1157	>	while (tab != null && i < tab.length) {
1158	>	int fh;
1159	>	Node<K,V> f = tabAt(tab, i);
1160	>	if (f == null)
1161	>	++i;
1162	>	else if ((fh = f.hash) == MOVED) {
1163	>	tab = helpTransfer(tab, f);
1164	>	i = 0; // restart
1165	>	}
1166	>	else {
1167	>	synchronized (f) {
1168	>	if (tabAt(tab, i) == f) {
1169	>	Node<K,V> p = (fh >= 0 ? f :
1170	>	(f instanceof TreeBin) ?
1171	>	((TreeBin<K,V>)f).first : null);
1172	>	while (p != null) {
1173	>	--delta;
1174	>	p = p.next;
1175	>	}
1176	>	setTabAt(tab, i++, null);
1177	>	}
1178	>	}
1179	>	}
1180	>	}
1181	>	if (delta != 0L)
1182	>	addCount(delta, -1);
1183	>	}
1184	>
1185	>	/**
1186	>	* Returns a {@link Set} view of the keys contained in this map.
1187	>	* The set is backed by the map, so changes to the map are
1188	>	* reflected in the set, and vice-versa. The set supports element
1189	>	* removal, which removes the corresponding mapping from this map,
1190	>	* via the {@code Iterator.remove}, {@code Set.remove},
1191	>	* {@code removeAll}, {@code retainAll}, and {@code clear}
1192	>	* operations.  It does not support the {@code add} or
1193	>	* {@code addAll} operations.
1194	>	*
1195	>	* <p>The view's iterators and spliterators are
1196	>	* <a href="package-summary.html#Weakly"><i>weakly consistent</i></a>.
1197	>	*
1198	>	* <p>The view's {@code spliterator} reports {@link Spliterator#CONCURRENT},
1199	>	* {@link Spliterator#DISTINCT}, and {@link Spliterator#NONNULL}.
1200	>	*
1201	>	* @return the set view
1202	>	*/
1203	>	public KeySetView<K,V> keySet() {
1204	>	KeySetView<K,V> ks;
1205	>	return (ks = keySet) != null ? ks : (keySet = new KeySetView<K,V>(this, null));
1206	>	}
1207	>
1208	>	/**
1209	>	* Returns a {@link Collection} view of the values contained in this map.
1210	>	* The collection is backed by the map, so changes to the map are
1211	>	* reflected in the collection, and vice-versa.  The collection
1212	>	* supports element removal, which removes the corresponding
1213	>	* mapping from this map, via the {@code Iterator.remove},
1214	>	* {@code Collection.remove}, {@code removeAll},
1215	>	* {@code retainAll}, and {@code clear} operations.  It does not
1216	>	* support the {@code add} or {@code addAll} operations.
1217	>	*
1218	>	* <p>The view's iterators and spliterators are
1219	>	* <a href="package-summary.html#Weakly"><i>weakly consistent</i></a>.
1220	>	*
1221	>	* <p>The view's {@code spliterator} reports {@link Spliterator#CONCURRENT}
1222	>	* and {@link Spliterator#NONNULL}.
1223	>	*
1224	>	* @return the collection view
1225	>	*/
1226	>	public Collection<V> values() {
1227	>	ValuesView<K,V> vs;
1228	>	return (vs = values) != null ? vs : (values = new ValuesView<K,V>(this));
1229	>	}
1230	>
1231	>	/**
1232	>	* Returns a {@link Set} view of the mappings contained in this map.
1233	>	* The set is backed by the map, so changes to the map are
1234	>	* reflected in the set, and vice-versa.  The set supports element
1235	>	* removal, which removes the corresponding mapping from the map,
1236	>	* via the {@code Iterator.remove}, {@code Set.remove},
1237	>	* {@code removeAll}, {@code retainAll}, and {@code clear}
1238	>	* operations.
1239	>	*
1240	>	* <p>The view's iterators and spliterators are
1241	>	* <a href="package-summary.html#Weakly"><i>weakly consistent</i></a>.
1242	>	*
1243	>	* <p>The view's {@code spliterator} reports {@link Spliterator#CONCURRENT},
1244	>	* {@link Spliterator#DISTINCT}, and {@link Spliterator#NONNULL}.
1245	>	*
1246	>	* @return the set view
1247	>	*/
1248	>	public Set<Map.Entry<K,V>> entrySet() {
1249	>	EntrySetView<K,V> es;
1250	>	return (es = entrySet) != null ? es : (entrySet = new EntrySetView<K,V>(this));
1251	>	}
1252	>
1253	>	/**
1254	>	* Returns the hash code value for this {@link Map}, i.e.,
1255	>	* the sum of, for each key-value pair in the map,
1256	>	* {@code key.hashCode() ^ value.hashCode()}.
1257	>	*
1258	>	* @return the hash code value for this map
1259	>	*/
1260	>	public int hashCode() {
1261	>	int h = 0;
1262	>	Node<K,V>[] t;
1263	>	if ((t = table) != null) {
1264	>	Traverser<K,V> it = new Traverser<K,V>(t, t.length, 0, t.length);
1265	>	for (Node<K,V> p; (p = it.advance()) != null; )
1266	>	h += p.key.hashCode() ^ p.val.hashCode();
1267	>	}
1268	>	return h;
1269	>	}
1270	>
1271	>	/**
1272	>	* Returns a string representation of this map.  The string
1273	>	* representation consists of a list of key-value mappings (in no
1274	>	* particular order) enclosed in braces ("{@code {}}").  Adjacent
1275	>	* mappings are separated by the characters {@code ", "} (comma
1276	>	* and space).  Each key-value mapping is rendered as the key
1277	>	* followed by an equals sign ("{@code =}") followed by the
1278	>	* associated value.
1279	>	*
1280	>	* @return a string representation of this map
1281	>	*/
1282	>	public String toString() {
1283	>	Node<K,V>[] t;
1284	>	int f = (t = table) == null ? 0 : t.length;
1285	>	Traverser<K,V> it = new Traverser<K,V>(t, f, 0, f);
1286	>	StringBuilder sb = new StringBuilder();
1287	>	sb.append('{');
1288	>	Node<K,V> p;
1289	>	if ((p = it.advance()) != null) {
1290	>	for (;;) {
1291	>	K k = p.key;
1292	>	V v = p.val;
1293	>	sb.append(k == this ? "(this Map)" : k);
1294	>	sb.append('=');
1295	>	sb.append(v == this ? "(this Map)" : v);
1296	>	if ((p = it.advance()) == null)
1297	>	break;
1298	>	sb.append(',').append(' ');
1299	>	}
1300	>	}
1301	>	return sb.append('}').toString();
1302	>	}
1303	>
1304	>	/**
1305	>	* Compares the specified object with this map for equality.
1306	>	* Returns {@code true} if the given object is a map with the same
1307	>	* mappings as this map.  This operation may return misleading
1308	>	* results if either map is concurrently modified during execution
1309	>	* of this method.
1310	>	*
1311	>	* @param o object to be compared for equality with this map
1312	>	* @return {@code true} if the specified object is equal to this map
1313	>	*/
1314	>	public boolean equals(Object o) {
1315	>	if (o != this) {
1316	>	if (!(o instanceof Map))
1317	>	return false;
1318	>	Map<?,?> m = (Map<?,?>) o;
1319	>	Node<K,V>[] t;
1320	>	int f = (t = table) == null ? 0 : t.length;
1321	>	Traverser<K,V> it = new Traverser<K,V>(t, f, 0, f);
1322	>	for (Node<K,V> p; (p = it.advance()) != null; ) {
1323	>	V val = p.val;
1324	>	Object v = m.get(p.key);
1325	>	if (v == null || (v != val && !v.equals(val)))
1326	>	return false;
1327	>	}
1328	>	for (Map.Entry<?,?> e : m.entrySet()) {
1329	>	Object mk, mv, v;
1330	>	if ((mk = e.getKey()) == null ||
1331	>	(mv = e.getValue()) == null ||
1332	>	(v = get(mk)) == null ||
1333	>	(mv != v && !mv.equals(v)))
1334	>	return false;
1335	>	}
1336	>	}
1337	>	return true;
1338	>	}
1339	>
1340	>	/**
1341	>	* Stripped-down version of helper class used in previous version,
1342	>	* declared for the sake of serialization compatibility
1343	>	*/
1344	>	static class Segment<K,V> extends ReentrantLock implements Serializable {
1345	>	private static final long serialVersionUID = 2249069246763182397L;
1346	>	final float loadFactor;
1347	>	Segment(float lf) { this.loadFactor = lf; }
1348	>	}
1349	>
1350	>	/**
1351	>	* Saves the state of the {@code ConcurrentHashMap} instance to a
1352	>	* stream (i.e., serializes it).
1353	>	* @param s the stream
1354	>	* @throws java.io.IOException if an I/O error occurs
1355	>	* @serialData
1356	>	* the key (Object) and value (Object)
1357	>	* for each key-value mapping, followed by a null pair.
1358	>	* The key-value mappings are emitted in no particular order.
1359	>	*/
1360	>	private void writeObject(java.io.ObjectOutputStream s)
1361	>	throws java.io.IOException {
1362	>	// For serialization compatibility
1363	>	// Emulate segment calculation from previous version of this class
1364	>	int sshift = 0;
1365	>	int ssize = 1;
1366	>	while (ssize < DEFAULT_CONCURRENCY_LEVEL) {
1367	>	++sshift;
1368	>	ssize <<= 1;
1369	>	}
1370	>	int segmentShift = 32 - sshift;
1371	>	int segmentMask = ssize - 1;
1372	>	@SuppressWarnings("unchecked")
1373	>	Segment<K,V>[] segments = (Segment<K,V>[])
1374	>	new Segment<?,?>[DEFAULT_CONCURRENCY_LEVEL];
1375	>	for (int i = 0; i < segments.length; ++i)
1376	>	segments[i] = new Segment<K,V>(LOAD_FACTOR);
1377	>	java.io.ObjectOutputStream.PutField streamFields = s.putFields();
1378	>	streamFields.put("segments", segments);
1379	>	streamFields.put("segmentShift", segmentShift);
1380	>	streamFields.put("segmentMask", segmentMask);
1381	>	s.writeFields();
1382	>
1383	>	Node<K,V>[] t;
1384	>	if ((t = table) != null) {
1385	>	Traverser<K,V> it = new Traverser<K,V>(t, t.length, 0, t.length);
1386	>	for (Node<K,V> p; (p = it.advance()) != null; ) {
1387	>	s.writeObject(p.key);
1388	>	s.writeObject(p.val);
1389	>	}
1390	>	}
1391	>	s.writeObject(null);
1392	>	s.writeObject(null);
1393	>	segments = null; // throw away
1394	>	}
1395	>
1396	>	/**
1397	>	* Reconstitutes the instance from a stream (that is, deserializes it).
1398	>	* @param s the stream
1399	>	* @throws ClassNotFoundException if the class of a serialized object
1400	>	*         could not be found
1401	>	* @throws java.io.IOException if an I/O error occurs
1402	>	*/
1403	>	private void readObject(java.io.ObjectInputStream s)
1404	>	throws java.io.IOException, ClassNotFoundException {
1405	>	/*
1406	>	* To improve performance in typical cases, we create nodes
1407	>	* while reading, then place in table once size is known.
1408	>	* However, we must also validate uniqueness and deal with
1409	>	* overpopulated bins while doing so, which requires
1410	>	* specialized versions of putVal mechanics.
1411	>	*/
1412	>	sizeCtl = -1; // force exclusion for table construction
1413	>	s.defaultReadObject();
1414	>	long size = 0L;
1415	>	Node<K,V> p = null;
1416	>	for (;;) {
1417	>	@SuppressWarnings("unchecked")
1418	>	K k = (K) s.readObject();
1419	>	@SuppressWarnings("unchecked")
1420	>	V v = (V) s.readObject();
1421	>	if (k != null && v != null) {
1422	>	p = new Node<K,V>(spread(k.hashCode()), k, v, p);
1423	>	++size;
1424	>	}
1425	>	else
1426	>	break;
1427	>	}
1428	>	if (size == 0L)
1429	>	sizeCtl = 0;
1430	>	else {
1431	>	int n;
1432	>	if (size >= (long)(MAXIMUM_CAPACITY >>> 1))
1433	>	n = MAXIMUM_CAPACITY;
1434	>	else {
1435	>	int sz = (int)size;
1436	>	n = tableSizeFor(sz + (sz >>> 1) + 1);
1437	>	}
1438	>	@SuppressWarnings("unchecked")
1439	>	Node<K,V>[] tab = (Node<K,V>[])new Node<?,?>[n];
1440	>	int mask = n - 1;
1441	>	long added = 0L;
1442	>	while (p != null) {
1443	>	boolean insertAtFront;
1444	>	Node<K,V> next = p.next, first;
1445	>	int h = p.hash, j = h & mask;
1446	>	if ((first = tabAt(tab, j)) == null)
1447	>	insertAtFront = true;
1448	>	else {
1449	>	K k = p.key;
1450	>	if (first.hash < 0) {
1451	>	TreeBin<K,V> t = (TreeBin<K,V>)first;
1452	>	if (t.putTreeVal(h, k, p.val) == null)
1453	>	++added;
1454	>	insertAtFront = false;
1455	>	}
1456	>	else {
1457	>	int binCount = 0;
1458	>	insertAtFront = true;
1459	>	Node<K,V> q; K qk;
1460	>	for (q = first; q != null; q = q.next) {
1461	>	if (q.hash == h &&
1462	>	((qk = q.key) == k ||
1463	>	(qk != null && k.equals(qk)))) {
1464	>	insertAtFront = false;
1465	>	break;
1466	>	}
1467	>	++binCount;
1468	>	}
1469	>	if (insertAtFront && binCount >= TREEIFY_THRESHOLD) {
1470	>	insertAtFront = false;
1471	>	++added;
1472	>	p.next = first;
1473	>	TreeNode<K,V> hd = null, tl = null;
1474	>	for (q = p; q != null; q = q.next) {
1475	>	TreeNode<K,V> t = new TreeNode<K,V>
1476	>	(q.hash, q.key, q.val, null, null);
1477	>	if ((t.prev = tl) == null)
1478	>	hd = t;
1479	>	else
1480	>	tl.next = t;
1481	>	tl = t;
1482	>	}
1483	>	setTabAt(tab, j, new TreeBin<K,V>(hd));
1484	>	}
1485	>	}
1486	>	}
1487	>	if (insertAtFront) {
1488	>	++added;
1489	>	p.next = first;
1490	>	setTabAt(tab, j, p);
1491	>	}
1492	>	p = next;
1493	>	}
1494	>	table = tab;
1495	>	sizeCtl = n - (n >>> 2);
1496	>	baseCount = added;
1497	>	}
1498	>	}
1499	>
1500	>	// ConcurrentMap methods
1501	>
1502	>	/**
1503	>	* {@inheritDoc}
1504	>	*
1505	>	* @return the previous value associated with the specified key,
1506	>	*         or {@code null} if there was no mapping for the key
1507	>	* @throws NullPointerException if the specified key or value is null
1508	>	*/
1509	>	public V putIfAbsent(K key, V value) {
1510	>	return putVal(key, value, true);
1511		}
1512
1513		/**
#	Line 925 | Line 1516 | public class ConcurrentHashMap<K, V> ext
1516		* @throws NullPointerException if the specified key is null
1517		*/
1518		public boolean remove(Object key, Object value) {
1519	<	int hash = hash(key.hashCode());
1520	<	if (value == null)
1521	<	return false;
931	<	return segmentFor(hash).remove(key, hash, value) != null;
1519	>	if (key == null)
1520	>	throw new NullPointerException();
1521	>	return value != null && replaceNode(key, null, value) != null;
1522		}
1523
1524		/**
#	Line 937 | Line 1527 | public class ConcurrentHashMap<K, V> ext
1527		* @throws NullPointerException if any of the arguments are null
1528		*/
1529		public boolean replace(K key, V oldValue, V newValue) {
1530	<	if (oldValue == null || newValue == null)
1530	>	if (key == null || oldValue == null || newValue == null)
1531		throw new NullPointerException();
1532	<	int hash = hash(key.hashCode());
943	<	return segmentFor(hash).replace(key, hash, oldValue, newValue);
1532	>	return replaceNode(key, newValue, oldValue) != null;
1533		}
1534
1535		/**
1536		* {@inheritDoc}
1537		*
1538		* @return the previous value associated with the specified key,
1539	<	*         or <tt>null</tt> if there was no mapping for the key
1539	>	*         or {@code null} if there was no mapping for the key
1540		* @throws NullPointerException if the specified key or value is null
1541		*/
1542		public V replace(K key, V value) {
1543	<	if (value == null)
1543	>	if (key == null || value == null)
1544		throw new NullPointerException();
1545	<	int hash = hash(key.hashCode());
957	<	return segmentFor(hash).replace(key, hash, value);
1545	>	return replaceNode(key, value, null);
1546		}
1547
1548	+	// Overrides of JDK8+ Map extension method defaults
1549	+
1550		/**
1551	<	* Removes all of the mappings from this map.
1551	>	* Returns the value to which the specified key is mapped, or the
1552	>	* given default value if this map contains no mapping for the
1553	>	* key.
1554	>	*
1555	>	* @param key the key whose associated value is to be returned
1556	>	* @param defaultValue the value to return if this map contains
1557	>	* no mapping for the given key
1558	>	* @return the mapping for the key, if present; else the default value
1559	>	* @throws NullPointerException if the specified key is null
1560		*/
1561	<	public void clear() {
1562	<	for (int i = 0; i < segments.length; ++i)
1563	<	segments[i].clear();
1561	>	public V getOrDefault(Object key, V defaultValue) {
1562	>	V v;
1563	>	return (v = get(key)) == null ? defaultValue : v;
1564	>	}
1565	>
1566	>	public void forEach(BiConsumer<? super K, ? super V> action) {
1567	>	if (action == null) throw new NullPointerException();
1568	>	Node<K,V>[] t;
1569	>	if ((t = table) != null) {
1570	>	Traverser<K,V> it = new Traverser<K,V>(t, t.length, 0, t.length);
1571	>	for (Node<K,V> p; (p = it.advance()) != null; ) {
1572	>	action.accept(p.key, p.val);
1573	>	}
1574	>	}
1575	>	}
1576	>
1577	>	public void replaceAll(BiFunction<? super K, ? super V, ? extends V> function) {
1578	>	if (function == null) throw new NullPointerException();
1579	>	Node<K,V>[] t;
1580	>	if ((t = table) != null) {
1581	>	Traverser<K,V> it = new Traverser<K,V>(t, t.length, 0, t.length);
1582	>	for (Node<K,V> p; (p = it.advance()) != null; ) {
1583	>	V oldValue = p.val;
1584	>	for (K key = p.key;;) {
1585	>	V newValue = function.apply(key, oldValue);
1586	>	if (newValue == null)
1587	>	throw new NullPointerException();
1588	>	if (replaceNode(key, newValue, oldValue) != null ||
1589	>	(oldValue = get(key)) == null)
1590	>	break;
1591	>	}
1592	>	}
1593	>	}
1594		}
1595
1596		/**
1597	<	* Returns a {@link Set} view of the keys contained in this map.
1598	<	* The set is backed by the map, so changes to the map are
1599	<	* reflected in the set, and vice-versa.  The set supports element
1600	<	* removal, which removes the corresponding mapping from this map,
1601	<	* via the <tt>Iterator.remove</tt>, <tt>Set.remove</tt>,
1602	<	* <tt>removeAll</tt>, <tt>retainAll</tt>, and <tt>clear</tt>
1603	<	* operations.  It does not support the <tt>add</tt> or
1604	<	* <tt>addAll</tt> operations.
1605	<	*
1606	<	* <p>The view's <tt>iterator</tt> is a "weakly consistent" iterator
1607	<	* that will never throw {@link ConcurrentModificationException},
1608	<	* and guarantees to traverse elements as they existed upon
1609	<	* construction of the iterator, and may (but is not guaranteed to)
1610	<	* reflect any modifications subsequent to construction.
1611	<	*/
1612	<	public Set<K> keySet() {
1613	<	Set<K> ks = keySet;
986	<	return (ks != null) ? ks : (keySet = new KeySet());
1597	>	* Helper method for EntrySet.removeIf
1598	>	*/
1599	>	boolean removeEntryIf(Predicate<? super Entry<K,V>> function) {
1600	>	if (function == null) throw new NullPointerException();
1601	>	Node<K,V>[] t;
1602	>	boolean removed = false;
1603	>	if ((t = table) != null) {
1604	>	Traverser<K,V> it = new Traverser<K,V>(t, t.length, 0, t.length);
1605	>	for (Node<K,V> p; (p = it.advance()) != null; ) {
1606	>	K k = p.key;
1607	>	V v = p.val;
1608	>	Map.Entry<K,V> e = new AbstractMap.SimpleImmutableEntry<>(k, v);
1609	>	if (function.test(e) && replaceNode(k, null, v) != null)
1610	>	removed = true;
1611	>	}
1612	>	}
1613	>	return removed;
1614		}
1615
1616		/**
1617	<	* Returns a {@link Collection} view of the values contained in this map.
991	<	* The collection is backed by the map, so changes to the map are
992	<	* 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.
998	<	*
999	<	* <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.
1617	>	* Helper method for Values.removeIf
1618		*/
1619	<	public Collection<V> values() {
1620	<	Collection<V> vs = values;
1621	<	return (vs != null) ? vs : (values = new Values());
1619	>	boolean removeValueIf(Predicate<? super  V> function) {
1620	>	if (function == null) throw new NullPointerException();
1621	>	Node<K,V>[] t;
1622	>	boolean removed = false;
1623	>	if ((t = table) != null) {
1624	>	Traverser<K,V> it = new Traverser<K,V>(t, t.length, 0, t.length);
1625	>	for (Node<K,V> p; (p = it.advance()) != null; ) {
1626	>	K k = p.key;
1627	>	V v = p.val;
1628	>	if (function.test(v) && replaceNode(k, null, v) != null)
1629	>	removed = true;
1630	>	}
1631	>	}
1632	>	return removed;
1633		}
1634
1635		/**
1636	<	* Returns a {@link Set} view of the mappings contained in this map.
1637	<	* The set is backed by the map, so changes to the map are
1638	<	* reflected in the set, and vice-versa.  The set supports element
1639	<	* removal, which removes the corresponding mapping from the map,
1640	<	* via the <tt>Iterator.remove</tt>, <tt>Set.remove</tt>,
1641	<	* <tt>removeAll</tt>, <tt>retainAll</tt>, and <tt>clear</tt>
1642	<	* operations.  It does not support the <tt>add</tt> or
1643	<	* <tt>addAll</tt> operations.
1644	<	*
1645	<	* <p>The view's <tt>iterator</tt> is a "weakly consistent" iterator
1646	<	* that will never throw {@link ConcurrentModificationException},
1647	<	* and guarantees to traverse elements as they existed upon
1648	<	* construction of the iterator, and may (but is not guaranteed to)
1649	<	* reflect any modifications subsequent to construction.
1636	>	* If the specified key is not already associated with a value,
1637	>	* attempts to compute its value using the given mapping function
1638	>	* and enters it into this map unless {@code null}.  The entire
1639	>	* method invocation is performed atomically, so the function is
1640	>	* applied at most once per key.  Some attempted update operations
1641	>	* on this map by other threads may be blocked while computation
1642	>	* is in progress, so the computation should be short and simple,
1643	>	* and must not attempt to update any other mappings of this map.
1644	>	*
1645	>	* @param key key with which the specified value is to be associated
1646	>	* @param mappingFunction the function to compute a value
1647	>	* @return the current (existing or computed) value associated with
1648	>	*         the specified key, or null if the computed value is null
1649	>	* @throws NullPointerException if the specified key or mappingFunction
1650	>	*         is null
1651	>	* @throws IllegalStateException if the computation detectably
1652	>	*         attempts a recursive update to this map that would
1653	>	*         otherwise never complete
1654	>	* @throws RuntimeException or Error if the mappingFunction does so,
1655	>	*         in which case the mapping is left unestablished
1656		*/
1657	<	public Set<Map.Entry<K,V>> entrySet() {
1658	<	Set<Map.Entry<K,V>> es = entrySet;
1659	<	return (es != null) ? es : (entrySet = new EntrySet());
1657	>	public V computeIfAbsent(K key, Function<? super K, ? extends V> mappingFunction) {
1658	>	if (key == null || mappingFunction == null)
1659	>	throw new NullPointerException();
1660	>	int h = spread(key.hashCode());
1661	>	V val = null;
1662	>	int binCount = 0;
1663	>	for (Node<K,V>[] tab = table;;) {
1664	>	Node<K,V> f; int n, i, fh;
1665	>	if (tab == null || (n = tab.length) == 0)
1666	>	tab = initTable();
1667	>	else if ((f = tabAt(tab, i = (n - 1) & h)) == null) {
1668	>	Node<K,V> r = new ReservationNode<K,V>();
1669	>	synchronized (r) {
1670	>	if (casTabAt(tab, i, null, r)) {
1671	>	binCount = 1;
1672	>	Node<K,V> node = null;
1673	>	try {
1674	>	if ((val = mappingFunction.apply(key)) != null)
1675	>	node = new Node<K,V>(h, key, val, null);
1676	>	} finally {
1677	>	setTabAt(tab, i, node);
1678	>	}
1679	>	}
1680	>	}
1681	>	if (binCount != 0)
1682	>	break;
1683	>	}
1684	>	else if ((fh = f.hash) == MOVED)
1685	>	tab = helpTransfer(tab, f);
1686	>	else {
1687	>	boolean added = false;
1688	>	synchronized (f) {
1689	>	if (tabAt(tab, i) == f) {
1690	>	if (fh >= 0) {
1691	>	binCount = 1;
1692	>	for (Node<K,V> e = f;; ++binCount) {
1693	>	K ek;
1694	>	if (e.hash == h &&
1695	>	((ek = e.key) == key ||
1696	>	(ek != null && key.equals(ek)))) {
1697	>	val = e.val;
1698	>	break;
1699	>	}
1700	>	Node<K,V> pred = e;
1701	>	if ((e = e.next) == null) {
1702	>	if ((val = mappingFunction.apply(key)) != null) {
1703	>	if (pred.next != null)
1704	>	throw new IllegalStateException("Recursive update");
1705	>	added = true;
1706	>	pred.next = new Node<K,V>(h, key, val, null);
1707	>	}
1708	>	break;
1709	>	}
1710	>	}
1711	>	}
1712	>	else if (f instanceof TreeBin) {
1713	>	binCount = 2;
1714	>	TreeBin<K,V> t = (TreeBin<K,V>)f;
1715	>	TreeNode<K,V> r, p;
1716	>	if ((r = t.root) != null &&
1717	>	(p = r.findTreeNode(h, key, null)) != null)
1718	>	val = p.val;
1719	>	else if ((val = mappingFunction.apply(key)) != null) {
1720	>	added = true;
1721	>	t.putTreeVal(h, key, val);
1722	>	}
1723	>	}
1724	>	else if (f instanceof ReservationNode)
1725	>	throw new IllegalStateException("Recursive update");
1726	>	}
1727	>	}
1728	>	if (binCount != 0) {
1729	>	if (binCount >= TREEIFY_THRESHOLD)
1730	>	treeifyBin(tab, i);
1731	>	if (!added)
1732	>	return val;
1733	>	break;
1734	>	}
1735	>	}
1736	>	}
1737	>	if (val != null)
1738	>	addCount(1L, binCount);
1739	>	return val;
1740	>	}
1741	>
1742	>	/**
1743	>	* If the value for the specified key is present, attempts to
1744	>	* compute a new mapping given the key and its current mapped
1745	>	* value.  The entire method invocation is performed atomically.
1746	>	* Some attempted update operations on this map by other threads
1747	>	* may be blocked while computation is in progress, so the
1748	>	* computation should be short and simple, and must not attempt to
1749	>	* update any other mappings of this map.
1750	>	*
1751	>	* @param key key with which a value may be associated
1752	>	* @param remappingFunction the function to compute a value
1753	>	* @return the new value associated with the specified key, or null if none
1754	>	* @throws NullPointerException if the specified key or remappingFunction
1755	>	*         is null
1756	>	* @throws IllegalStateException if the computation detectably
1757	>	*         attempts a recursive update to this map that would
1758	>	*         otherwise never complete
1759	>	* @throws RuntimeException or Error if the remappingFunction does so,
1760	>	*         in which case the mapping is unchanged
1761	>	*/
1762	>	public V computeIfPresent(K key, BiFunction<? super K, ? super V, ? extends V> remappingFunction) {
1763	>	if (key == null || remappingFunction == null)
1764	>	throw new NullPointerException();
1765	>	int h = spread(key.hashCode());
1766	>	V val = null;
1767	>	int delta = 0;
1768	>	int binCount = 0;
1769	>	for (Node<K,V>[] tab = table;;) {
1770	>	Node<K,V> f; int n, i, fh;
1771	>	if (tab == null || (n = tab.length) == 0)
1772	>	tab = initTable();
1773	>	else if ((f = tabAt(tab, i = (n - 1) & h)) == null)
1774	>	break;
1775	>	else if ((fh = f.hash) == MOVED)
1776	>	tab = helpTransfer(tab, f);
1777	>	else {
1778	>	synchronized (f) {
1779	>	if (tabAt(tab, i) == f) {
1780	>	if (fh >= 0) {
1781	>	binCount = 1;
1782	>	for (Node<K,V> e = f, pred = null;; ++binCount) {
1783	>	K ek;
1784	>	if (e.hash == h &&
1785	>	((ek = e.key) == key ||
1786	>	(ek != null && key.equals(ek)))) {
1787	>	val = remappingFunction.apply(key, e.val);
1788	>	if (val != null)
1789	>	e.val = val;
1790	>	else {
1791	>	delta = -1;
1792	>	Node<K,V> en = e.next;
1793	>	if (pred != null)
1794	>	pred.next = en;
1795	>	else
1796	>	setTabAt(tab, i, en);
1797	>	}
1798	>	break;
1799	>	}
1800	>	pred = e;
1801	>	if ((e = e.next) == null)
1802	>	break;
1803	>	}
1804	>	}
1805	>	else if (f instanceof TreeBin) {
1806	>	binCount = 2;
1807	>	TreeBin<K,V> t = (TreeBin<K,V>)f;
1808	>	TreeNode<K,V> r, p;
1809	>	if ((r = t.root) != null &&
1810	>	(p = r.findTreeNode(h, key, null)) != null) {
1811	>	val = remappingFunction.apply(key, p.val);
1812	>	if (val != null)
1813	>	p.val = val;
1814	>	else {
1815	>	delta = -1;
1816	>	if (t.removeTreeNode(p))
1817	>	setTabAt(tab, i, untreeify(t.first));
1818	>	}
1819	>	}
1820	>	}
1821	>	else if (f instanceof ReservationNode)
1822	>	throw new IllegalStateException("Recursive update");
1823	>	}
1824	>	}
1825	>	if (binCount != 0)
1826	>	break;
1827	>	}
1828	>	}
1829	>	if (delta != 0)
1830	>	addCount((long)delta, binCount);
1831	>	return val;
1832	>	}
1833	>
1834	>	/**
1835	>	* Attempts to compute a mapping for the specified key and its
1836	>	* current mapped value (or {@code null} if there is no current
1837	>	* mapping). The entire method invocation is performed atomically.
1838	>	* Some attempted update operations on this map by other threads
1839	>	* may be blocked while computation is in progress, so the
1840	>	* computation should be short and simple, and must not attempt to
1841	>	* update any other mappings of this Map.
1842	>	*
1843	>	* @param key key with which the specified value is to be associated
1844	>	* @param remappingFunction the function to compute a value
1845	>	* @return the new value associated with the specified key, or null if none
1846	>	* @throws NullPointerException if the specified key or remappingFunction
1847	>	*         is null
1848	>	* @throws IllegalStateException if the computation detectably
1849	>	*         attempts a recursive update to this map that would
1850	>	*         otherwise never complete
1851	>	* @throws RuntimeException or Error if the remappingFunction does so,
1852	>	*         in which case the mapping is unchanged
1853	>	*/
1854	>	public V compute(K key,
1855	>	BiFunction<? super K, ? super V, ? extends V> remappingFunction) {
1856	>	if (key == null || remappingFunction == null)
1857	>	throw new NullPointerException();
1858	>	int h = spread(key.hashCode());
1859	>	V val = null;
1860	>	int delta = 0;
1861	>	int binCount = 0;
1862	>	for (Node<K,V>[] tab = table;;) {
1863	>	Node<K,V> f; int n, i, fh;
1864	>	if (tab == null || (n = tab.length) == 0)
1865	>	tab = initTable();
1866	>	else if ((f = tabAt(tab, i = (n - 1) & h)) == null) {
1867	>	Node<K,V> r = new ReservationNode<K,V>();
1868	>	synchronized (r) {
1869	>	if (casTabAt(tab, i, null, r)) {
1870	>	binCount = 1;
1871	>	Node<K,V> node = null;
1872	>	try {
1873	>	if ((val = remappingFunction.apply(key, null)) != null) {
1874	>	delta = 1;
1875	>	node = new Node<K,V>(h, key, val, null);
1876	>	}
1877	>	} finally {
1878	>	setTabAt(tab, i, node);
1879	>	}
1880	>	}
1881	>	}
1882	>	if (binCount != 0)
1883	>	break;
1884	>	}
1885	>	else if ((fh = f.hash) == MOVED)
1886	>	tab = helpTransfer(tab, f);
1887	>	else {
1888	>	synchronized (f) {
1889	>	if (tabAt(tab, i) == f) {
1890	>	if (fh >= 0) {
1891	>	binCount = 1;
1892	>	for (Node<K,V> e = f, pred = null;; ++binCount) {
1893	>	K ek;
1894	>	if (e.hash == h &&
1895	>	((ek = e.key) == key ||
1896	>	(ek != null && key.equals(ek)))) {
1897	>	val = remappingFunction.apply(key, e.val);
1898	>	if (val != null)
1899	>	e.val = val;
1900	>	else {
1901	>	delta = -1;
1902	>	Node<K,V> en = e.next;
1903	>	if (pred != null)
1904	>	pred.next = en;
1905	>	else
1906	>	setTabAt(tab, i, en);
1907	>	}
1908	>	break;
1909	>	}
1910	>	pred = e;
1911	>	if ((e = e.next) == null) {
1912	>	val = remappingFunction.apply(key, null);
1913	>	if (val != null) {
1914	>	if (pred.next != null)
1915	>	throw new IllegalStateException("Recursive update");
1916	>	delta = 1;
1917	>	pred.next =
1918	>	new Node<K,V>(h, key, val, null);
1919	>	}
1920	>	break;
1921	>	}
1922	>	}
1923	>	}
1924	>	else if (f instanceof TreeBin) {
1925	>	binCount = 1;
1926	>	TreeBin<K,V> t = (TreeBin<K,V>)f;
1927	>	TreeNode<K,V> r, p;
1928	>	if ((r = t.root) != null)
1929	>	p = r.findTreeNode(h, key, null);
1930	>	else
1931	>	p = null;
1932	>	V pv = (p == null) ? null : p.val;
1933	>	val = remappingFunction.apply(key, pv);
1934	>	if (val != null) {
1935	>	if (p != null)
1936	>	p.val = val;
1937	>	else {
1938	>	delta = 1;
1939	>	t.putTreeVal(h, key, val);
1940	>	}
1941	>	}
1942	>	else if (p != null) {
1943	>	delta = -1;
1944	>	if (t.removeTreeNode(p))
1945	>	setTabAt(tab, i, untreeify(t.first));
1946	>	}
1947	>	}
1948	>	else if (f instanceof ReservationNode)
1949	>	throw new IllegalStateException("Recursive update");
1950	>	}
1951	>	}
1952	>	if (binCount != 0) {
1953	>	if (binCount >= TREEIFY_THRESHOLD)
1954	>	treeifyBin(tab, i);
1955	>	break;
1956	>	}
1957	>	}
1958	>	}
1959	>	if (delta != 0)
1960	>	addCount((long)delta, binCount);
1961	>	return val;
1962	>	}
1963	>
1964	>	/**
1965	>	* If the specified key is not already associated with a
1966	>	* (non-null) value, associates it with the given value.
1967	>	* Otherwise, replaces the value with the results of the given
1968	>	* remapping function, or removes if {@code null}. The entire
1969	>	* method invocation is performed atomically.  Some attempted
1970	>	* update operations on this map by other threads may be blocked
1971	>	* while computation is in progress, so the computation should be
1972	>	* short and simple, and must not attempt to update any other
1973	>	* mappings of this Map.
1974	>	*
1975	>	* @param key key with which the specified value is to be associated
1976	>	* @param value the value to use if absent
1977	>	* @param remappingFunction the function to recompute a value if present
1978	>	* @return the new value associated with the specified key, or null if none
1979	>	* @throws NullPointerException if the specified key or the
1980	>	*         remappingFunction is null
1981	>	* @throws RuntimeException or Error if the remappingFunction does so,
1982	>	*         in which case the mapping is unchanged
1983	>	*/
1984	>	public V merge(K key, V value, BiFunction<? super V, ? super V, ? extends V> remappingFunction) {
1985	>	if (key == null || value == null || remappingFunction == null)
1986	>	throw new NullPointerException();
1987	>	int h = spread(key.hashCode());
1988	>	V val = null;
1989	>	int delta = 0;
1990	>	int binCount = 0;
1991	>	for (Node<K,V>[] tab = table;;) {
1992	>	Node<K,V> f; int n, i, fh;
1993	>	if (tab == null || (n = tab.length) == 0)
1994	>	tab = initTable();
1995	>	else if ((f = tabAt(tab, i = (n - 1) & h)) == null) {
1996	>	if (casTabAt(tab, i, null, new Node<K,V>(h, key, value, null))) {
1997	>	delta = 1;
1998	>	val = value;
1999	>	break;
2000	>	}
2001	>	}
2002	>	else if ((fh = f.hash) == MOVED)
2003	>	tab = helpTransfer(tab, f);
2004	>	else {
2005	>	synchronized (f) {
2006	>	if (tabAt(tab, i) == f) {
2007	>	if (fh >= 0) {
2008	>	binCount = 1;
2009	>	for (Node<K,V> e = f, pred = null;; ++binCount) {
2010	>	K ek;
2011	>	if (e.hash == h &&
2012	>	((ek = e.key) == key ||
2013	>	(ek != null && key.equals(ek)))) {
2014	>	val = remappingFunction.apply(e.val, value);
2015	>	if (val != null)
2016	>	e.val = val;
2017	>	else {
2018	>	delta = -1;
2019	>	Node<K,V> en = e.next;
2020	>	if (pred != null)
2021	>	pred.next = en;
2022	>	else
2023	>	setTabAt(tab, i, en);
2024	>	}
2025	>	break;
2026	>	}
2027	>	pred = e;
2028	>	if ((e = e.next) == null) {
2029	>	delta = 1;
2030	>	val = value;
2031	>	pred.next =
2032	>	new Node<K,V>(h, key, val, null);
2033	>	break;
2034	>	}
2035	>	}
2036	>	}
2037	>	else if (f instanceof TreeBin) {
2038	>	binCount = 2;
2039	>	TreeBin<K,V> t = (TreeBin<K,V>)f;
2040	>	TreeNode<K,V> r = t.root;
2041	>	TreeNode<K,V> p = (r == null) ? null :
2042	>	r.findTreeNode(h, key, null);
2043	>	val = (p == null) ? value :
2044	>	remappingFunction.apply(p.val, value);
2045	>	if (val != null) {
2046	>	if (p != null)
2047	>	p.val = val;
2048	>	else {
2049	>	delta = 1;
2050	>	t.putTreeVal(h, key, val);
2051	>	}
2052	>	}
2053	>	else if (p != null) {
2054	>	delta = -1;
2055	>	if (t.removeTreeNode(p))
2056	>	setTabAt(tab, i, untreeify(t.first));
2057	>	}
2058	>	}
2059	>	else if (f instanceof ReservationNode)
2060	>	throw new IllegalStateException("Recursive update");
2061	>	}
2062	>	}
2063	>	if (binCount != 0) {
2064	>	if (binCount >= TREEIFY_THRESHOLD)
2065	>	treeifyBin(tab, i);
2066	>	break;
2067	>	}
2068	>	}
2069	>	}
2070	>	if (delta != 0)
2071	>	addCount((long)delta, binCount);
2072	>	return val;
2073	>	}
2074	>
2075	>	// Hashtable legacy methods
2076	>
2077	>	/**
2078	>	* Legacy method testing if some key maps into the specified value
2079	>	* in this table.
2080	>	*
2081	>	* @deprecated This method is identical in functionality to
2082	>	* {@link #containsValue(Object)}, and exists solely to ensure
2083	>	* full compatibility with class {@link java.util.Hashtable},
2084	>	* which supported this method prior to introduction of the
2085	>	* Java Collections framework.
2086	>	*
2087	>	* @param  value a value to search for
2088	>	* @return {@code true} if and only if some key maps to the
2089	>	*         {@code value} argument in this table as
2090	>	*         determined by the {@code equals} method;
2091	>	*         {@code false} otherwise
2092	>	* @throws NullPointerException if the specified value is null
2093	>	*/
2094	>	@Deprecated
2095	>	public boolean contains(Object value) {
2096	>	return containsValue(value);
2097		}
2098
2099		/**
2100		* Returns an enumeration of the keys in this table.
2101		*
2102		* @return an enumeration of the keys in this table
2103	<	* @see #keySet
2103	>	* @see #keySet()
2104		*/
2105		public Enumeration<K> keys() {
2106	<	return new KeyIterator();
2106	>	Node<K,V>[] t;
2107	>	int f = (t = table) == null ? 0 : t.length;
2108	>	return new KeyIterator<K,V>(t, f, 0, f, this);
2109		}
2110
2111		/**
2112		* Returns an enumeration of the values in this table.
2113		*
2114		* @return an enumeration of the values in this table
2115	<	* @see #values
2115	>	* @see #values()
2116		*/
2117		public Enumeration<V> elements() {
2118	<	return new ValueIterator();
2118	>	Node<K,V>[] t;
2119	>	int f = (t = table) == null ? 0 : t.length;
2120	>	return new ValueIterator<K,V>(t, f, 0, f, this);
2121		}
2122
2123	<	/* ---------------- Iterator Support -------------- */
2123	>	// ConcurrentHashMap-only methods
2124
2125	<	abstract class HashIterator {
2126	<	int nextSegmentIndex;
2127	<	int nextTableIndex;
2128	<	HashEntry<K,V>[] currentTable;
2129	<	HashEntry<K, V> nextEntry;
2130	<	HashEntry<K, V> lastReturned;
2125	>	/**
2126	>	* Returns the number of mappings. This method should be used
2127	>	* instead of {@link #size} because a ConcurrentHashMap may
2128	>	* contain more mappings than can be represented as an int. The
2129	>	* value returned is an estimate; the actual count may differ if
2130	>	* there are concurrent insertions or removals.
2131	>	*
2132	>	* @return the number of mappings
2133	>	* @since 1.8
2134	>	*/
2135	>	public long mappingCount() {
2136	>	long n = sumCount();
2137	>	return (n < 0L) ? 0L : n; // ignore transient negative values
2138	>	}
2139
2140	<	HashIterator() {
2141	<	nextSegmentIndex = segments.length - 1;
2142	<	nextTableIndex = -1;
2143	<	advance();
2140	>	/**
2141	>	* Creates a new {@link Set} backed by a ConcurrentHashMap
2142	>	* from the given type to {@code Boolean.TRUE}.
2143	>	*
2144	>	* @param <K> the element type of the returned set
2145	>	* @return the new set
2146	>	* @since 1.8
2147	>	*/
2148	>	public static <K> KeySetView<K,Boolean> newKeySet() {
2149	>	return new KeySetView<K,Boolean>
2150	>	(new ConcurrentHashMap<K,Boolean>(), Boolean.TRUE);
2151	>	}
2152	>
2153	>	/**
2154	>	* Creates a new {@link Set} backed by a ConcurrentHashMap
2155	>	* from the given type to {@code Boolean.TRUE}.
2156	>	*
2157	>	* @param initialCapacity The implementation performs internal
2158	>	* sizing to accommodate this many elements.
2159	>	* @param <K> the element type of the returned set
2160	>	* @return the new set
2161	>	* @throws IllegalArgumentException if the initial capacity of
2162	>	* elements is negative
2163	>	* @since 1.8
2164	>	*/
2165	>	public static <K> KeySetView<K,Boolean> newKeySet(int initialCapacity) {
2166	>	return new KeySetView<K,Boolean>
2167	>	(new ConcurrentHashMap<K,Boolean>(initialCapacity), Boolean.TRUE);
2168	>	}
2169	>
2170	>	/**
2171	>	* Returns a {@link Set} view of the keys in this map, using the
2172	>	* given common mapped value for any additions (i.e., {@link
2173	>	* Collection#add} and {@link Collection#addAll(Collection)}).
2174	>	* This is of course only appropriate if it is acceptable to use
2175	>	* the same value for all additions from this view.
2176	>	*
2177	>	* @param mappedValue the mapped value to use for any additions
2178	>	* @return the set view
2179	>	* @throws NullPointerException if the mappedValue is null
2180	>	*/
2181	>	public KeySetView<K,V> keySet(V mappedValue) {
2182	>	if (mappedValue == null)
2183	>	throw new NullPointerException();
2184	>	return new KeySetView<K,V>(this, mappedValue);
2185	>	}
2186	>
2187	>	/* ---------------- Special Nodes -------------- */
2188	>
2189	>	/**
2190	>	* A node inserted at head of bins during transfer operations.
2191	>	*/
2192	>	static final class ForwardingNode<K,V> extends Node<K,V> {
2193	>	final Node<K,V>[] nextTable;
2194	>	ForwardingNode(Node<K,V>[] tab) {
2195	>	super(MOVED, null, null, null);
2196	>	this.nextTable = tab;
2197	>	}
2198	>
2199	>	Node<K,V> find(int h, Object k) {
2200	>	// loop to avoid arbitrarily deep recursion on forwarding nodes
2201	>	outer: for (Node<K,V>[] tab = nextTable;;) {
2202	>	Node<K,V> e; int n;
2203	>	if (k == null || tab == null || (n = tab.length) == 0 ||
2204	>	(e = tabAt(tab, (n - 1) & h)) == null)
2205	>	return null;
2206	>	for (;;) {
2207	>	int eh; K ek;
2208	>	if ((eh = e.hash) == h &&
2209	>	((ek = e.key) == k || (ek != null && k.equals(ek))))
2210	>	return e;
2211	>	if (eh < 0) {
2212	>	if (e instanceof ForwardingNode) {
2213	>	tab = ((ForwardingNode<K,V>)e).nextTable;
2214	>	continue outer;
2215	>	}
2216	>	else
2217	>	return e.find(h, k);
2218	>	}
2219	>	if ((e = e.next) == null)
2220	>	return null;
2221	>	}
2222	>	}
2223		}
2224	+	}
2225	+
2226	+	/**
2227	+	* A place-holder node used in computeIfAbsent and compute
2228	+	*/
2229	+	static final class ReservationNode<K,V> extends Node<K,V> {
2230	+	ReservationNode() {
2231	+	super(RESERVED, null, null, null);
2232	+	}
2233	+
2234	+	Node<K,V> find(int h, Object k) {
2235	+	return null;
2236	+	}
2237	+	}
2238	+
2239	+	/* ---------------- Table Initialization and Resizing -------------- */
2240	+
2241	+	/**
2242	+	* Returns the stamp bits for resizing a table of size n.
2243	+	* Must be negative when shifted left by RESIZE_STAMP_SHIFT.
2244	+	*/
2245	+	static final int resizeStamp(int n) {
2246	+	return Integer.numberOfLeadingZeros(n) | (1 << (RESIZE_STAMP_BITS - 1));
2247	+	}
2248
2249	<	public boolean hasMoreElements() { return hasNext(); }
2249	>	/**
2250	>	* Initializes table, using the size recorded in sizeCtl.
2251	>	*/
2252	>	private final Node<K,V>[] initTable() {
2253	>	Node<K,V>[] tab; int sc;
2254	>	while ((tab = table) == null || tab.length == 0) {
2255	>	if ((sc = sizeCtl) < 0)
2256	>	Thread.yield(); // lost initialization race; just spin
2257	>	else if (U.compareAndSwapInt(this, SIZECTL, sc, -1)) {
2258	>	try {
2259	>	if ((tab = table) == null || tab.length == 0) {
2260	>	int n = (sc > 0) ? sc : DEFAULT_CAPACITY;
2261	>	@SuppressWarnings("unchecked")
2262	>	Node<K,V>[] nt = (Node<K,V>[])new Node<?,?>[n];
2263	>	table = tab = nt;
2264	>	sc = n - (n >>> 2);
2265	>	}
2266	>	} finally {
2267	>	sizeCtl = sc;
2268	>	}
2269	>	break;
2270	>	}
2271	>	}
2272	>	return tab;
2273	>	}
2274
2275	<	final void advance() {
2276	<	if (nextEntry != null && (nextEntry = nextEntry.next) != null)
2275	>	/**
2276	>	* Adds to count, and if table is too small and not already
2277	>	* resizing, initiates transfer. If already resizing, helps
2278	>	* perform transfer if work is available.  Rechecks occupancy
2279	>	* after a transfer to see if another resize is already needed
2280	>	* because resizings are lagging additions.
2281	>	*
2282	>	* @param x the count to add
2283	>	* @param check if <0, don't check resize, if <= 1 only check if uncontended
2284	>	*/
2285	>	private final void addCount(long x, int check) {
2286	>	CounterCell[] as; long b, s;
2287	>	if ((as = counterCells) != null ||
2288	>	!U.compareAndSwapLong(this, BASECOUNT, b = baseCount, s = b + x)) {
2289	>	CounterCell a; long v; int m;
2290	>	boolean uncontended = true;
2291	>	if (as == null || (m = as.length - 1) < 0 ||
2292	>	(a = as[ThreadLocalRandom.getProbe() & m]) == null ||
2293	>	!(uncontended =
2294	>	U.compareAndSwapLong(a, CELLVALUE, v = a.value, v + x))) {
2295	>	fullAddCount(x, uncontended);
2296	>	return;
2297	>	}
2298	>	if (check <= 1)
2299		return;
2300	+	s = sumCount();
2301	+	}
2302	+	if (check >= 0) {
2303	+	Node<K,V>[] tab, nt; int n, sc;
2304	+	while (s >= (long)(sc = sizeCtl) && (tab = table) != null &&
2305	+	(n = tab.length) < MAXIMUM_CAPACITY) {
2306	+	int rs = resizeStamp(n);
2307	+	if (sc < 0) {
2308	+	if ((sc >>> RESIZE_STAMP_SHIFT) != rs || sc == rs + 1 ||
2309	+	sc == rs + MAX_RESIZERS || (nt = nextTable) == null ||
2310	+	transferIndex <= 0)
2311	+	break;
2312	+	if (U.compareAndSwapInt(this, SIZECTL, sc, sc + 1))
2313	+	transfer(tab, nt);
2314	+	}
2315	+	else if (U.compareAndSwapInt(this, SIZECTL, sc,
2316	+	(rs << RESIZE_STAMP_SHIFT) + 2))
2317	+	transfer(tab, null);
2318	+	s = sumCount();
2319	+	}
2320	+	}
2321	+	}
2322	+
2323	+	/**
2324	+	* Helps transfer if a resize is in progress.
2325	+	*/
2326	+	final Node<K,V>[] helpTransfer(Node<K,V>[] tab, Node<K,V> f) {
2327	+	Node<K,V>[] nextTab; int sc;
2328	+	if (tab != null && (f instanceof ForwardingNode) &&
2329	+	(nextTab = ((ForwardingNode<K,V>)f).nextTable) != null) {
2330	+	int rs = resizeStamp(tab.length);
2331	+	while (nextTab == nextTable && table == tab &&
2332	+	(sc = sizeCtl) < 0) {
2333	+	if ((sc >>> RESIZE_STAMP_SHIFT) != rs || sc == rs + 1 ||
2334	+	sc == rs + MAX_RESIZERS || transferIndex <= 0)
2335	+	break;
2336	+	if (U.compareAndSwapInt(this, SIZECTL, sc, sc + 1)) {
2337	+	transfer(tab, nextTab);
2338	+	break;
2339	+	}
2340	+	}
2341	+	return nextTab;
2342	+	}
2343	+	return table;
2344	+	}
2345
2346	<	while (nextTableIndex >= 0) {
2347	<	if ( (nextEntry = currentTable[nextTableIndex--]) != null)
2346	>	/**
2347	>	* Tries to presize table to accommodate the given number of elements.
2348	>	*
2349	>	* @param size number of elements (doesn't need to be perfectly accurate)
2350	>	*/
2351	>	private final void tryPresize(int size) {
2352	>	int c = (size >= (MAXIMUM_CAPACITY >>> 1)) ? MAXIMUM_CAPACITY :
2353	>	tableSizeFor(size + (size >>> 1) + 1);
2354	>	int sc;
2355	>	while ((sc = sizeCtl) >= 0) {
2356	>	Node<K,V>[] tab = table; int n;
2357	>	if (tab == null || (n = tab.length) == 0) {
2358	>	n = (sc > c) ? sc : c;
2359	>	if (U.compareAndSwapInt(this, SIZECTL, sc, -1)) {
2360	>	try {
2361	>	if (table == tab) {
2362	>	@SuppressWarnings("unchecked")
2363	>	Node<K,V>[] nt = (Node<K,V>[])new Node<?,?>[n];
2364	>	table = nt;
2365	>	sc = n - (n >>> 2);
2366	>	}
2367	>	} finally {
2368	>	sizeCtl = sc;
2369	>	}
2370	>	}
2371	>	}
2372	>	else if (c <= sc || n >= MAXIMUM_CAPACITY)
2373	>	break;
2374	>	else if (tab == table) {
2375	>	int rs = resizeStamp(n);
2376	>	if (U.compareAndSwapInt(this, SIZECTL, sc,
2377	>	(rs << RESIZE_STAMP_SHIFT) + 2))
2378	>	transfer(tab, null);
2379	>	}
2380	>	}
2381	>	}
2382	>
2383	>	/**
2384	>	* Moves and/or copies the nodes in each bin to new table. See
2385	>	* above for explanation.
2386	>	*/
2387	>	private final void transfer(Node<K,V>[] tab, Node<K,V>[] nextTab) {
2388	>	int n = tab.length, stride;
2389	>	if ((stride = (NCPU > 1) ? (n >>> 3) / NCPU : n) < MIN_TRANSFER_STRIDE)
2390	>	stride = MIN_TRANSFER_STRIDE; // subdivide range
2391	>	if (nextTab == null) {            // initiating
2392	>	try {
2393	>	@SuppressWarnings("unchecked")
2394	>	Node<K,V>[] nt = (Node<K,V>[])new Node<?,?>[n << 1];
2395	>	nextTab = nt;
2396	>	} catch (Throwable ex) {      // try to cope with OOME
2397	>	sizeCtl = Integer.MAX_VALUE;
2398	>	return;
2399	>	}
2400	>	nextTable = nextTab;
2401	>	transferIndex = n;
2402	>	}
2403	>	int nextn = nextTab.length;
2404	>	ForwardingNode<K,V> fwd = new ForwardingNode<K,V>(nextTab);
2405	>	boolean advance = true;
2406	>	boolean finishing = false; // to ensure sweep before committing nextTab
2407	>	for (int i = 0, bound = 0;;) {
2408	>	Node<K,V> f; int fh;
2409	>	while (advance) {
2410	>	int nextIndex, nextBound;
2411	>	if (--i >= bound || finishing)
2412	>	advance = false;
2413	>	else if ((nextIndex = transferIndex) <= 0) {
2414	>	i = -1;
2415	>	advance = false;
2416	>	}
2417	>	else if (U.compareAndSwapInt
2418	>	(this, TRANSFERINDEX, nextIndex,
2419	>	nextBound = (nextIndex > stride ?
2420	>	nextIndex - stride : 0))) {
2421	>	bound = nextBound;
2422	>	i = nextIndex - 1;
2423	>	advance = false;
2424	>	}
2425	>	}
2426	>	if (i < 0 || i >= n || i + n >= nextn) {
2427	>	int sc;
2428	>	if (finishing) {
2429	>	nextTable = null;
2430	>	table = nextTab;
2431	>	sizeCtl = (n << 1) - (n >>> 1);
2432		return;
2433	+	}
2434	+	if (U.compareAndSwapInt(this, SIZECTL, sc = sizeCtl, sc - 1)) {
2435	+	if ((sc - 2) != resizeStamp(n) << RESIZE_STAMP_SHIFT)
2436	+	return;
2437	+	finishing = advance = true;
2438	+	i = n; // recheck before commit
2439	+	}
2440	+	}
2441	+	else if ((f = tabAt(tab, i)) == null)
2442	+	advance = casTabAt(tab, i, null, fwd);
2443	+	else if ((fh = f.hash) == MOVED)
2444	+	advance = true; // already processed
2445	+	else {
2446	+	synchronized (f) {
2447	+	if (tabAt(tab, i) == f) {
2448	+	Node<K,V> ln, hn;
2449	+	if (fh >= 0) {
2450	+	int runBit = fh & n;
2451	+	Node<K,V> lastRun = f;
2452	+	for (Node<K,V> p = f.next; p != null; p = p.next) {
2453	+	int b = p.hash & n;
2454	+	if (b != runBit) {
2455	+	runBit = b;
2456	+	lastRun = p;
2457	+	}
2458	+	}
2459	+	if (runBit == 0) {
2460	+	ln = lastRun;
2461	+	hn = null;
2462	+	}
2463	+	else {
2464	+	hn = lastRun;
2465	+	ln = null;
2466	+	}
2467	+	for (Node<K,V> p = f; p != lastRun; p = p.next) {
2468	+	int ph = p.hash; K pk = p.key; V pv = p.val;
2469	+	if ((ph & n) == 0)
2470	+	ln = new Node<K,V>(ph, pk, pv, ln);
2471	+	else
2472	+	hn = new Node<K,V>(ph, pk, pv, hn);
2473	+	}
2474	+	setTabAt(nextTab, i, ln);
2475	+	setTabAt(nextTab, i + n, hn);
2476	+	setTabAt(tab, i, fwd);
2477	+	advance = true;
2478	+	}
2479	+	else if (f instanceof TreeBin) {
2480	+	TreeBin<K,V> t = (TreeBin<K,V>)f;
2481	+	TreeNode<K,V> lo = null, loTail = null;
2482	+	TreeNode<K,V> hi = null, hiTail = null;
2483	+	int lc = 0, hc = 0;
2484	+	for (Node<K,V> e = t.first; e != null; e = e.next) {
2485	+	int h = e.hash;
2486	+	TreeNode<K,V> p = new TreeNode<K,V>
2487	+	(h, e.key, e.val, null, null);
2488	+	if ((h & n) == 0) {
2489	+	if ((p.prev = loTail) == null)
2490	+	lo = p;
2491	+	else
2492	+	loTail.next = p;
2493	+	loTail = p;
2494	+	++lc;
2495	+	}
2496	+	else {
2497	+	if ((p.prev = hiTail) == null)
2498	+	hi = p;
2499	+	else
2500	+	hiTail.next = p;
2501	+	hiTail = p;
2502	+	++hc;
2503	+	}
2504	+	}
2505	+	ln = (lc <= UNTREEIFY_THRESHOLD) ? untreeify(lo) :
2506	+	(hc != 0) ? new TreeBin<K,V>(lo) : t;
2507	+	hn = (hc <= UNTREEIFY_THRESHOLD) ? untreeify(hi) :
2508	+	(lc != 0) ? new TreeBin<K,V>(hi) : t;
2509	+	setTabAt(nextTab, i, ln);
2510	+	setTabAt(nextTab, i + n, hn);
2511	+	setTabAt(tab, i, fwd);
2512	+	advance = true;
2513	+	}
2514	+	}
2515	+	}
2516	+	}
2517	+	}
2518	+	}
2519	+
2520	+	/* ---------------- Counter support -------------- */
2521	+
2522	+	/**
2523	+	* A padded cell for distributing counts.  Adapted from LongAdder
2524	+	* and Striped64.  See their internal docs for explanation.
2525	+	*/
2526	+	@sun.misc.Contended static final class CounterCell {
2527	+	volatile long value;
2528	+	CounterCell(long x) { value = x; }
2529	+	}
2530	+
2531	+	final long sumCount() {
2532	+	CounterCell[] as = counterCells; CounterCell a;
2533	+	long sum = baseCount;
2534	+	if (as != null) {
2535	+	for (int i = 0; i < as.length; ++i) {
2536	+	if ((a = as[i]) != null)
2537	+	sum += a.value;
2538		}
2539	+	}
2540	+	return sum;
2541	+	}
2542
2543	<	while (nextSegmentIndex >= 0) {
2544	<	Segment<K,V> seg = segments[nextSegmentIndex--];
2545	<	if (seg.count != 0) {
2546	<	currentTable = seg.table;
2547	<	for (int j = currentTable.length - 1; j >= 0; --j) {
2548	<	if ( (nextEntry = currentTable[j]) != null) {
2549	<	nextTableIndex = j - 1;
2550	<	return;
2543	>	// See LongAdder version for explanation
2544	>	private final void fullAddCount(long x, boolean wasUncontended) {
2545	>	int h;
2546	>	if ((h = ThreadLocalRandom.getProbe()) == 0) {
2547	>	ThreadLocalRandom.localInit();      // force initialization
2548	>	h = ThreadLocalRandom.getProbe();
2549	>	wasUncontended = true;
2550	>	}
2551	>	boolean collide = false;                // True if last slot nonempty
2552	>	for (;;) {
2553	>	CounterCell[] as; CounterCell a; int n; long v;
2554	>	if ((as = counterCells) != null && (n = as.length) > 0) {
2555	>	if ((a = as[(n - 1) & h]) == null) {
2556	>	if (cellsBusy == 0) {            // Try to attach new Cell
2557	>	CounterCell r = new CounterCell(x); // Optimistic create
2558	>	if (cellsBusy == 0 &&
2559	>	U.compareAndSwapInt(this, CELLSBUSY, 0, 1)) {
2560	>	boolean created = false;
2561	>	try {               // Recheck under lock
2562	>	CounterCell[] rs; int m, j;
2563	>	if ((rs = counterCells) != null &&
2564	>	(m = rs.length) > 0 &&
2565	>	rs[j = (m - 1) & h] == null) {
2566	>	rs[j] = r;
2567	>	created = true;
2568	>	}
2569	>	} finally {
2570	>	cellsBusy = 0;
2571	>	}
2572	>	if (created)
2573	>	break;
2574	>	continue;           // Slot is now non-empty
2575		}
2576		}
2577	+	collide = false;
2578		}
2579	+	else if (!wasUncontended)       // CAS already known to fail
2580	+	wasUncontended = true;      // Continue after rehash
2581	+	else if (U.compareAndSwapLong(a, CELLVALUE, v = a.value, v + x))
2582	+	break;
2583	+	else if (counterCells != as || n >= NCPU)
2584	+	collide = false;            // At max size or stale
2585	+	else if (!collide)
2586	+	collide = true;
2587	+	else if (cellsBusy == 0 &&
2588	+	U.compareAndSwapInt(this, CELLSBUSY, 0, 1)) {
2589	+	try {
2590	+	if (counterCells == as) {// Expand table unless stale
2591	+	CounterCell[] rs = new CounterCell[n << 1];
2592	+	for (int i = 0; i < n; ++i)
2593	+	rs[i] = as[i];
2594	+	counterCells = rs;
2595	+	}
2596	+	} finally {
2597	+	cellsBusy = 0;
2598	+	}
2599	+	collide = false;
2600	+	continue;                   // Retry with expanded table
2601	+	}
2602	+	h = ThreadLocalRandom.advanceProbe(h);
2603		}
2604	+	else if (cellsBusy == 0 && counterCells == as &&
2605	+	U.compareAndSwapInt(this, CELLSBUSY, 0, 1)) {
2606	+	boolean init = false;
2607	+	try {                           // Initialize table
2608	+	if (counterCells == as) {
2609	+	CounterCell[] rs = new CounterCell[2];
2610	+	rs[h & 1] = new CounterCell(x);
2611	+	counterCells = rs;
2612	+	init = true;
2613	+	}
2614	+	} finally {
2615	+	cellsBusy = 0;
2616	+	}
2617	+	if (init)
2618	+	break;
2619	+	}
2620	+	else if (U.compareAndSwapLong(this, BASECOUNT, v = baseCount, v + x))
2621	+	break;                          // Fall back on using base
2622		}
2623	+	}
2624
2625	<	public boolean hasNext() { return nextEntry != null; }
2625	>	/* ---------------- Conversion from/to TreeBins -------------- */
2626
2627	<	HashEntry<K,V> nextEntry() {
2628	<	if (nextEntry == null)
2629	<	throw new NoSuchElementException();
2630	<	lastReturned = nextEntry;
2627	>	/**
2628	>	* Replaces all linked nodes in bin at given index unless table is
2629	>	* too small, in which case resizes instead.
2630	>	*/
2631	>	private final void treeifyBin(Node<K,V>[] tab, int index) {
2632	>	Node<K,V> b; int n;
2633	>	if (tab != null) {
2634	>	if ((n = tab.length) < MIN_TREEIFY_CAPACITY)
2635	>	tryPresize(n << 1);
2636	>	else if ((b = tabAt(tab, index)) != null && b.hash >= 0) {
2637	>	synchronized (b) {
2638	>	if (tabAt(tab, index) == b) {
2639	>	TreeNode<K,V> hd = null, tl = null;
2640	>	for (Node<K,V> e = b; e != null; e = e.next) {
2641	>	TreeNode<K,V> p =
2642	>	new TreeNode<K,V>(e.hash, e.key, e.val,
2643	>	null, null);
2644	>	if ((p.prev = tl) == null)
2645	>	hd = p;
2646	>	else
2647	>	tl.next = p;
2648	>	tl = p;
2649	>	}
2650	>	setTabAt(tab, index, new TreeBin<K,V>(hd));
2651	>	}
2652	>	}
2653	>	}
2654	>	}
2655	>	}
2656	>
2657	>	/**
2658	>	* Returns a list on non-TreeNodes replacing those in given list.
2659	>	*/
2660	>	static <K,V> Node<K,V> untreeify(Node<K,V> b) {
2661	>	Node<K,V> hd = null, tl = null;
2662	>	for (Node<K,V> q = b; q != null; q = q.next) {
2663	>	Node<K,V> p = new Node<K,V>(q.hash, q.key, q.val, null);
2664	>	if (tl == null)
2665	>	hd = p;
2666	>	else
2667	>	tl.next = p;
2668	>	tl = p;
2669	>	}
2670	>	return hd;
2671	>	}
2672	>
2673	>	/* ---------------- TreeNodes -------------- */
2674	>
2675	>	/**
2676	>	* Nodes for use in TreeBins
2677	>	*/
2678	>	static final class TreeNode<K,V> extends Node<K,V> {
2679	>	TreeNode<K,V> parent;  // red-black tree links
2680	>	TreeNode<K,V> left;
2681	>	TreeNode<K,V> right;
2682	>	TreeNode<K,V> prev;    // needed to unlink next upon deletion
2683	>	boolean red;
2684	>
2685	>	TreeNode(int hash, K key, V val, Node<K,V> next,
2686	>	TreeNode<K,V> parent) {
2687	>	super(hash, key, val, next);
2688	>	this.parent = parent;
2689	>	}
2690	>
2691	>	Node<K,V> find(int h, Object k) {
2692	>	return findTreeNode(h, k, null);
2693	>	}
2694	>
2695	>	/**
2696	>	* Returns the TreeNode (or null if not found) for the given key
2697	>	* starting at given root.
2698	>	*/
2699	>	final TreeNode<K,V> findTreeNode(int h, Object k, Class<?> kc) {
2700	>	if (k != null) {
2701	>	TreeNode<K,V> p = this;
2702	>	do {
2703	>	int ph, dir; K pk; TreeNode<K,V> q;
2704	>	TreeNode<K,V> pl = p.left, pr = p.right;
2705	>	if ((ph = p.hash) > h)
2706	>	p = pl;
2707	>	else if (ph < h)
2708	>	p = pr;
2709	>	else if ((pk = p.key) == k || (pk != null && k.equals(pk)))
2710	>	return p;
2711	>	else if (pl == null)
2712	>	p = pr;
2713	>	else if (pr == null)
2714	>	p = pl;
2715	>	else if ((kc != null ||
2716	>	(kc = comparableClassFor(k)) != null) &&
2717	>	(dir = compareComparables(kc, k, pk)) != 0)
2718	>	p = (dir < 0) ? pl : pr;
2719	>	else if ((q = pr.findTreeNode(h, k, kc)) != null)
2720	>	return q;
2721	>	else
2722	>	p = pl;
2723	>	} while (p != null);
2724	>	}
2725	>	return null;
2726	>	}
2727	>	}
2728	>
2729	>	/* ---------------- TreeBins -------------- */
2730	>
2731	>	/**
2732	>	* TreeNodes used at the heads of bins. TreeBins do not hold user
2733	>	* keys or values, but instead point to list of TreeNodes and
2734	>	* their root. They also maintain a parasitic read-write lock
2735	>	* forcing writers (who hold bin lock) to wait for readers (who do
2736	>	* not) to complete before tree restructuring operations.
2737	>	*/
2738	>	static final class TreeBin<K,V> extends Node<K,V> {
2739	>	TreeNode<K,V> root;
2740	>	volatile TreeNode<K,V> first;
2741	>	volatile Thread waiter;
2742	>	volatile int lockState;
2743	>	// values for lockState
2744	>	static final int WRITER = 1; // set while holding write lock
2745	>	static final int WAITER = 2; // set when waiting for write lock
2746	>	static final int READER = 4; // increment value for setting read lock
2747	>
2748	>	/**
2749	>	* Tie-breaking utility for ordering insertions when equal
2750	>	* hashCodes and non-comparable. We don't require a total
2751	>	* order, just a consistent insertion rule to maintain
2752	>	* equivalence across rebalancings. Tie-breaking further than
2753	>	* necessary simplifies testing a bit.
2754	>	*/
2755	>	static int tieBreakOrder(Object a, Object b) {
2756	>	int d;
2757	>	if (a == null || b == null ||
2758	>	(d = a.getClass().getName().
2759	>	compareTo(b.getClass().getName())) == 0)
2760	>	d = (System.identityHashCode(a) <= System.identityHashCode(b) ?
2761	>	-1 : 1);
2762	>	return d;
2763	>	}
2764	>
2765	>	/**
2766	>	* Creates bin with initial set of nodes headed by b.
2767	>	*/
2768	>	TreeBin(TreeNode<K,V> b) {
2769	>	super(TREEBIN, null, null, null);
2770	>	this.first = b;
2771	>	TreeNode<K,V> r = null;
2772	>	for (TreeNode<K,V> x = b, next; x != null; x = next) {
2773	>	next = (TreeNode<K,V>)x.next;
2774	>	x.left = x.right = null;
2775	>	if (r == null) {
2776	>	x.parent = null;
2777	>	x.red = false;
2778	>	r = x;
2779	>	}
2780	>	else {
2781	>	K k = x.key;
2782	>	int h = x.hash;
2783	>	Class<?> kc = null;
2784	>	for (TreeNode<K,V> p = r;;) {
2785	>	int dir, ph;
2786	>	K pk = p.key;
2787	>	if ((ph = p.hash) > h)
2788	>	dir = -1;
2789	>	else if (ph < h)
2790	>	dir = 1;
2791	>	else if ((kc == null &&
2792	>	(kc = comparableClassFor(k)) == null) ||
2793	>	(dir = compareComparables(kc, k, pk)) == 0)
2794	>	dir = tieBreakOrder(k, pk);
2795	>	TreeNode<K,V> xp = p;
2796	>	if ((p = (dir <= 0) ? p.left : p.right) == null) {
2797	>	x.parent = xp;
2798	>	if (dir <= 0)
2799	>	xp.left = x;
2800	>	else
2801	>	xp.right = x;
2802	>	r = balanceInsertion(r, x);
2803	>	break;
2804	>	}
2805	>	}
2806	>	}
2807	>	}
2808	>	this.root = r;
2809	>	assert checkInvariants(root);
2810	>	}
2811	>
2812	>	/**
2813	>	* Acquires write lock for tree restructuring.
2814	>	*/
2815	>	private final void lockRoot() {
2816	>	if (!U.compareAndSwapInt(this, LOCKSTATE, 0, WRITER))
2817	>	contendedLock(); // offload to separate method
2818	>	}
2819	>
2820	>	/**
2821	>	* Releases write lock for tree restructuring.
2822	>	*/
2823	>	private final void unlockRoot() {
2824	>	lockState = 0;
2825	>	}
2826	>
2827	>	/**
2828	>	* Possibly blocks awaiting root lock.
2829	>	*/
2830	>	private final void contendedLock() {
2831	>	boolean waiting = false;
2832	>	for (int s;;) {
2833	>	if (((s = lockState) & ~WAITER) == 0) {
2834	>	if (U.compareAndSwapInt(this, LOCKSTATE, s, WRITER)) {
2835	>	if (waiting)
2836	>	waiter = null;
2837	>	return;
2838	>	}
2839	>	}
2840	>	else if ((s & WAITER) == 0) {
2841	>	if (U.compareAndSwapInt(this, LOCKSTATE, s, s | WAITER)) {
2842	>	waiting = true;
2843	>	waiter = Thread.currentThread();
2844	>	}
2845	>	}
2846	>	else if (waiting)
2847	>	LockSupport.park(this);
2848	>	}
2849	>	}
2850	>
2851	>	/**
2852	>	* Returns matching node or null if none. Tries to search
2853	>	* using tree comparisons from root, but continues linear
2854	>	* search when lock not available.
2855	>	*/
2856	>	final Node<K,V> find(int h, Object k) {
2857	>	if (k != null) {
2858	>	for (Node<K,V> e = first; e != null; ) {
2859	>	int s; K ek;
2860	>	if (((s = lockState) & (WAITER|WRITER)) != 0) {
2861	>	if (e.hash == h &&
2862	>	((ek = e.key) == k || (ek != null && k.equals(ek))))
2863	>	return e;
2864	>	e = e.next;
2865	>	}
2866	>	else if (U.compareAndSwapInt(this, LOCKSTATE, s,
2867	>	s + READER)) {
2868	>	TreeNode<K,V> r, p;
2869	>	try {
2870	>	p = ((r = root) == null ? null :
2871	>	r.findTreeNode(h, k, null));
2872	>	} finally {
2873	>	Thread w;
2874	>	if (U.getAndAddInt(this, LOCKSTATE, -READER) ==
2875	>	(READER|WAITER) && (w = waiter) != null)
2876	>	LockSupport.unpark(w);
2877	>	}
2878	>	return p;
2879	>	}
2880	>	}
2881	>	}
2882	>	return null;
2883	>	}
2884	>
2885	>	/**
2886	>	* Finds or adds a node.
2887	>	* @return null if added
2888	>	*/
2889	>	final TreeNode<K,V> putTreeVal(int h, K k, V v) {
2890	>	Class<?> kc = null;
2891	>	boolean searched = false;
2892	>	for (TreeNode<K,V> p = root;;) {
2893	>	int dir, ph; K pk;
2894	>	if (p == null) {
2895	>	first = root = new TreeNode<K,V>(h, k, v, null, null);
2896	>	break;
2897	>	}
2898	>	else if ((ph = p.hash) > h)
2899	>	dir = -1;
2900	>	else if (ph < h)
2901	>	dir = 1;
2902	>	else if ((pk = p.key) == k || (pk != null && k.equals(pk)))
2903	>	return p;
2904	>	else if ((kc == null &&
2905	>	(kc = comparableClassFor(k)) == null) ||
2906	>	(dir = compareComparables(kc, k, pk)) == 0) {
2907	>	if (!searched) {
2908	>	TreeNode<K,V> q, ch;
2909	>	searched = true;
2910	>	if (((ch = p.left) != null &&
2911	>	(q = ch.findTreeNode(h, k, kc)) != null) ||
2912	>	((ch = p.right) != null &&
2913	>	(q = ch.findTreeNode(h, k, kc)) != null))
2914	>	return q;
2915	>	}
2916	>	dir = tieBreakOrder(k, pk);
2917	>	}
2918	>
2919	>	TreeNode<K,V> xp = p;
2920	>	if ((p = (dir <= 0) ? p.left : p.right) == null) {
2921	>	TreeNode<K,V> x, f = first;
2922	>	first = x = new TreeNode<K,V>(h, k, v, f, xp);
2923	>	if (f != null)
2924	>	f.prev = x;
2925	>	if (dir <= 0)
2926	>	xp.left = x;
2927	>	else
2928	>	xp.right = x;
2929	>	if (!xp.red)
2930	>	x.red = true;
2931	>	else {
2932	>	lockRoot();
2933	>	try {
2934	>	root = balanceInsertion(root, x);
2935	>	} finally {
2936	>	unlockRoot();
2937	>	}
2938	>	}
2939	>	break;
2940	>	}
2941	>	}
2942	>	assert checkInvariants(root);
2943	>	return null;
2944	>	}
2945	>
2946	>	/**
2947	>	* Removes the given node, that must be present before this
2948	>	* call.  This is messier than typical red-black deletion code
2949	>	* because we cannot swap the contents of an interior node
2950	>	* with a leaf successor that is pinned by "next" pointers
2951	>	* that are accessible independently of lock. So instead we
2952	>	* swap the tree linkages.
2953	>	*
2954	>	* @return true if now too small, so should be untreeified
2955	>	*/
2956	>	final boolean removeTreeNode(TreeNode<K,V> p) {
2957	>	TreeNode<K,V> next = (TreeNode<K,V>)p.next;
2958	>	TreeNode<K,V> pred = p.prev;  // unlink traversal pointers
2959	>	TreeNode<K,V> r, rl;
2960	>	if (pred == null)
2961	>	first = next;
2962	>	else
2963	>	pred.next = next;
2964	>	if (next != null)
2965	>	next.prev = pred;
2966	>	if (first == null) {
2967	>	root = null;
2968	>	return true;
2969	>	}
2970	>	if ((r = root) == null || r.right == null || // too small
2971	>	(rl = r.left) == null || rl.left == null)
2972	>	return true;
2973	>	lockRoot();
2974	>	try {
2975	>	TreeNode<K,V> replacement;
2976	>	TreeNode<K,V> pl = p.left;
2977	>	TreeNode<K,V> pr = p.right;
2978	>	if (pl != null && pr != null) {
2979	>	TreeNode<K,V> s = pr, sl;
2980	>	while ((sl = s.left) != null) // find successor
2981	>	s = sl;
2982	>	boolean c = s.red; s.red = p.red; p.red = c; // swap colors
2983	>	TreeNode<K,V> sr = s.right;
2984	>	TreeNode<K,V> pp = p.parent;
2985	>	if (s == pr) { // p was s's direct parent
2986	>	p.parent = s;
2987	>	s.right = p;
2988	>	}
2989	>	else {
2990	>	TreeNode<K,V> sp = s.parent;
2991	>	if ((p.parent = sp) != null) {
2992	>	if (s == sp.left)
2993	>	sp.left = p;
2994	>	else
2995	>	sp.right = p;
2996	>	}
2997	>	if ((s.right = pr) != null)
2998	>	pr.parent = s;
2999	>	}
3000	>	p.left = null;
3001	>	if ((p.right = sr) != null)
3002	>	sr.parent = p;
3003	>	if ((s.left = pl) != null)
3004	>	pl.parent = s;
3005	>	if ((s.parent = pp) == null)
3006	>	r = s;
3007	>	else if (p == pp.left)
3008	>	pp.left = s;
3009	>	else
3010	>	pp.right = s;
3011	>	if (sr != null)
3012	>	replacement = sr;
3013	>	else
3014	>	replacement = p;
3015	>	}
3016	>	else if (pl != null)
3017	>	replacement = pl;
3018	>	else if (pr != null)
3019	>	replacement = pr;
3020	>	else
3021	>	replacement = p;
3022	>	if (replacement != p) {
3023	>	TreeNode<K,V> pp = replacement.parent = p.parent;
3024	>	if (pp == null)
3025	>	r = replacement;
3026	>	else if (p == pp.left)
3027	>	pp.left = replacement;
3028	>	else
3029	>	pp.right = replacement;
3030	>	p.left = p.right = p.parent = null;
3031	>	}
3032	>
3033	>	root = (p.red) ? r : balanceDeletion(r, replacement);
3034	>
3035	>	if (p == replacement) {  // detach pointers
3036	>	TreeNode<K,V> pp;
3037	>	if ((pp = p.parent) != null) {
3038	>	if (p == pp.left)
3039	>	pp.left = null;
3040	>	else if (p == pp.right)
3041	>	pp.right = null;
3042	>	p.parent = null;
3043	>	}
3044	>	}
3045	>	} finally {
3046	>	unlockRoot();
3047	>	}
3048	>	assert checkInvariants(root);
3049	>	return false;
3050	>	}
3051	>
3052	>	/* ------------------------------------------------------------ */
3053	>	// Red-black tree methods, all adapted from CLR
3054	>
3055	>	static <K,V> TreeNode<K,V> rotateLeft(TreeNode<K,V> root,
3056	>	TreeNode<K,V> p) {
3057	>	TreeNode<K,V> r, pp, rl;
3058	>	if (p != null && (r = p.right) != null) {
3059	>	if ((rl = p.right = r.left) != null)
3060	>	rl.parent = p;
3061	>	if ((pp = r.parent = p.parent) == null)
3062	>	(root = r).red = false;
3063	>	else if (pp.left == p)
3064	>	pp.left = r;
3065	>	else
3066	>	pp.right = r;
3067	>	r.left = p;
3068	>	p.parent = r;
3069	>	}
3070	>	return root;
3071	>	}
3072	>
3073	>	static <K,V> TreeNode<K,V> rotateRight(TreeNode<K,V> root,
3074	>	TreeNode<K,V> p) {
3075	>	TreeNode<K,V> l, pp, lr;
3076	>	if (p != null && (l = p.left) != null) {
3077	>	if ((lr = p.left = l.right) != null)
3078	>	lr.parent = p;
3079	>	if ((pp = l.parent = p.parent) == null)
3080	>	(root = l).red = false;
3081	>	else if (pp.right == p)
3082	>	pp.right = l;
3083	>	else
3084	>	pp.left = l;
3085	>	l.right = p;
3086	>	p.parent = l;
3087	>	}
3088	>	return root;
3089	>	}
3090	>
3091	>	static <K,V> TreeNode<K,V> balanceInsertion(TreeNode<K,V> root,
3092	>	TreeNode<K,V> x) {
3093	>	x.red = true;
3094	>	for (TreeNode<K,V> xp, xpp, xppl, xppr;;) {
3095	>	if ((xp = x.parent) == null) {
3096	>	x.red = false;
3097	>	return x;
3098	>	}
3099	>	else if (!xp.red || (xpp = xp.parent) == null)
3100	>	return root;
3101	>	if (xp == (xppl = xpp.left)) {
3102	>	if ((xppr = xpp.right) != null && xppr.red) {
3103	>	xppr.red = false;
3104	>	xp.red = false;
3105	>	xpp.red = true;
3106	>	x = xpp;
3107	>	}
3108	>	else {
3109	>	if (x == xp.right) {
3110	>	root = rotateLeft(root, x = xp);
3111	>	xpp = (xp = x.parent) == null ? null : xp.parent;
3112	>	}
3113	>	if (xp != null) {
3114	>	xp.red = false;
3115	>	if (xpp != null) {
3116	>	xpp.red = true;
3117	>	root = rotateRight(root, xpp);
3118	>	}
3119	>	}
3120	>	}
3121	>	}
3122	>	else {
3123	>	if (xppl != null && xppl.red) {
3124	>	xppl.red = false;
3125	>	xp.red = false;
3126	>	xpp.red = true;
3127	>	x = xpp;
3128	>	}
3129	>	else {
3130	>	if (x == xp.left) {
3131	>	root = rotateRight(root, x = xp);
3132	>	xpp = (xp = x.parent) == null ? null : xp.parent;
3133	>	}
3134	>	if (xp != null) {
3135	>	xp.red = false;
3136	>	if (xpp != null) {
3137	>	xpp.red = true;
3138	>	root = rotateLeft(root, xpp);
3139	>	}
3140	>	}
3141	>	}
3142	>	}
3143	>	}
3144	>	}
3145	>
3146	>	static <K,V> TreeNode<K,V> balanceDeletion(TreeNode<K,V> root,
3147	>	TreeNode<K,V> x) {
3148	>	for (TreeNode<K,V> xp, xpl, xpr;;) {
3149	>	if (x == null || x == root)
3150	>	return root;
3151	>	else if ((xp = x.parent) == null) {
3152	>	x.red = false;
3153	>	return x;
3154	>	}
3155	>	else if (x.red) {
3156	>	x.red = false;
3157	>	return root;
3158	>	}
3159	>	else if ((xpl = xp.left) == x) {
3160	>	if ((xpr = xp.right) != null && xpr.red) {
3161	>	xpr.red = false;
3162	>	xp.red = true;
3163	>	root = rotateLeft(root, xp);
3164	>	xpr = (xp = x.parent) == null ? null : xp.right;
3165	>	}
3166	>	if (xpr == null)
3167	>	x = xp;
3168	>	else {
3169	>	TreeNode<K,V> sl = xpr.left, sr = xpr.right;
3170	>	if ((sr == null || !sr.red) &&
3171	>	(sl == null || !sl.red)) {
3172	>	xpr.red = true;
3173	>	x = xp;
3174	>	}
3175	>	else {
3176	>	if (sr == null || !sr.red) {
3177	>	if (sl != null)
3178	>	sl.red = false;
3179	>	xpr.red = true;
3180	>	root = rotateRight(root, xpr);
3181	>	xpr = (xp = x.parent) == null ?
3182	>	null : xp.right;
3183	>	}
3184	>	if (xpr != null) {
3185	>	xpr.red = (xp == null) ? false : xp.red;
3186	>	if ((sr = xpr.right) != null)
3187	>	sr.red = false;
3188	>	}
3189	>	if (xp != null) {
3190	>	xp.red = false;
3191	>	root = rotateLeft(root, xp);
3192	>	}
3193	>	x = root;
3194	>	}
3195	>	}
3196	>	}
3197	>	else { // symmetric
3198	>	if (xpl != null && xpl.red) {
3199	>	xpl.red = false;
3200	>	xp.red = true;
3201	>	root = rotateRight(root, xp);
3202	>	xpl = (xp = x.parent) == null ? null : xp.left;
3203	>	}
3204	>	if (xpl == null)
3205	>	x = xp;
3206	>	else {
3207	>	TreeNode<K,V> sl = xpl.left, sr = xpl.right;
3208	>	if ((sl == null || !sl.red) &&
3209	>	(sr == null || !sr.red)) {
3210	>	xpl.red = true;
3211	>	x = xp;
3212	>	}
3213	>	else {
3214	>	if (sl == null || !sl.red) {
3215	>	if (sr != null)
3216	>	sr.red = false;
3217	>	xpl.red = true;
3218	>	root = rotateLeft(root, xpl);
3219	>	xpl = (xp = x.parent) == null ?
3220	>	null : xp.left;
3221	>	}
3222	>	if (xpl != null) {
3223	>	xpl.red = (xp == null) ? false : xp.red;
3224	>	if ((sl = xpl.left) != null)
3225	>	sl.red = false;
3226	>	}
3227	>	if (xp != null) {
3228	>	xp.red = false;
3229	>	root = rotateRight(root, xp);
3230	>	}
3231	>	x = root;
3232	>	}
3233	>	}
3234	>	}
3235	>	}
3236	>	}
3237	>
3238	>	/**
3239	>	* Recursive invariant check
3240	>	*/
3241	>	static <K,V> boolean checkInvariants(TreeNode<K,V> t) {
3242	>	TreeNode<K,V> tp = t.parent, tl = t.left, tr = t.right,
3243	>	tb = t.prev, tn = (TreeNode<K,V>)t.next;
3244	>	if (tb != null && tb.next != t)
3245	>	return false;
3246	>	if (tn != null && tn.prev != t)
3247	>	return false;
3248	>	if (tp != null && t != tp.left && t != tp.right)
3249	>	return false;
3250	>	if (tl != null && (tl.parent != t || tl.hash > t.hash))
3251	>	return false;
3252	>	if (tr != null && (tr.parent != t || tr.hash < t.hash))
3253	>	return false;
3254	>	if (t.red && tl != null && tl.red && tr != null && tr.red)
3255	>	return false;
3256	>	if (tl != null && !checkInvariants(tl))
3257	>	return false;
3258	>	if (tr != null && !checkInvariants(tr))
3259	>	return false;
3260	>	return true;
3261	>	}
3262	>
3263	>	private static final sun.misc.Unsafe U = sun.misc.Unsafe.getUnsafe();
3264	>	private static final long LOCKSTATE;
3265	>	static {
3266	>	try {
3267	>	LOCKSTATE = U.objectFieldOffset
3268	>	(TreeBin.class.getDeclaredField("lockState"));
3269	>	} catch (ReflectiveOperationException e) {
3270	>	throw new Error(e);
3271	>	}
3272	>	}
3273	>	}
3274	>
3275	>	/* ----------------Table Traversal -------------- */
3276	>
3277	>	/**
3278	>	* Records the table, its length, and current traversal index for a
3279	>	* traverser that must process a region of a forwarded table before
3280	>	* proceeding with current table.
3281	>	*/
3282	>	static final class TableStack<K,V> {
3283	>	int length;
3284	>	int index;
3285	>	Node<K,V>[] tab;
3286	>	TableStack<K,V> next;
3287	>	}
3288	>
3289	>	/**
3290	>	* Encapsulates traversal for methods such as containsValue; also
3291	>	* serves as a base class for other iterators and spliterators.
3292	>	*
3293	>	* Method advance visits once each still-valid node that was
3294	>	* reachable upon iterator construction. It might miss some that
3295	>	* were added to a bin after the bin was visited, which is OK wrt
3296	>	* consistency guarantees. Maintaining this property in the face
3297	>	* of possible ongoing resizes requires a fair amount of
3298	>	* bookkeeping state that is difficult to optimize away amidst
3299	>	* volatile accesses.  Even so, traversal maintains reasonable
3300	>	* throughput.
3301	>	*
3302	>	* Normally, iteration proceeds bin-by-bin traversing lists.
3303	>	* However, if the table has been resized, then all future steps
3304	>	* must traverse both the bin at the current index as well as at
3305	>	* (index + baseSize); and so on for further resizings. To
3306	>	* paranoically cope with potential sharing by users of iterators
3307	>	* across threads, iteration terminates if a bounds checks fails
3308	>	* for a table read.
3309	>	*/
3310	>	static class Traverser<K,V> {
3311	>	Node<K,V>[] tab;        // current table; updated if resized
3312	>	Node<K,V> next;         // the next entry to use
3313	>	TableStack<K,V> stack, spare; // to save/restore on ForwardingNodes
3314	>	int index;              // index of bin to use next
3315	>	int baseIndex;          // current index of initial table
3316	>	int baseLimit;          // index bound for initial table
3317	>	final int baseSize;     // initial table size
3318	>
3319	>	Traverser(Node<K,V>[] tab, int size, int index, int limit) {
3320	>	this.tab = tab;
3321	>	this.baseSize = size;
3322	>	this.baseIndex = this.index = index;
3323	>	this.baseLimit = limit;
3324	>	this.next = null;
3325	>	}
3326	>
3327	>	/**
3328	>	* Advances if possible, returning next valid node, or null if none.
3329	>	*/
3330	>	final Node<K,V> advance() {
3331	>	Node<K,V> e;
3332	>	if ((e = next) != null)
3333	>	e = e.next;
3334	>	for (;;) {
3335	>	Node<K,V>[] t; int i, n;  // must use locals in checks
3336	>	if (e != null)
3337	>	return next = e;
3338	>	if (baseIndex >= baseLimit || (t = tab) == null ||
3339	>	(n = t.length) <= (i = index) || i < 0)
3340	>	return next = null;
3341	>	if ((e = tabAt(t, i)) != null && e.hash < 0) {
3342	>	if (e instanceof ForwardingNode) {
3343	>	tab = ((ForwardingNode<K,V>)e).nextTable;
3344	>	e = null;
3345	>	pushState(t, i, n);
3346	>	continue;
3347	>	}
3348	>	else if (e instanceof TreeBin)
3349	>	e = ((TreeBin<K,V>)e).first;
3350	>	else
3351	>	e = null;
3352	>	}
3353	>	if (stack != null)
3354	>	recoverState(n);
3355	>	else if ((index = i + baseSize) >= n)
3356	>	index = ++baseIndex; // visit upper slots if present
3357	>	}
3358	>	}
3359	>
3360	>	/**
3361	>	* Saves traversal state upon encountering a forwarding node.
3362	>	*/
3363	>	private void pushState(Node<K,V>[] t, int i, int n) {
3364	>	TableStack<K,V> s = spare;  // reuse if possible
3365	>	if (s != null)
3366	>	spare = s.next;
3367	>	else
3368	>	s = new TableStack<K,V>();
3369	>	s.tab = t;
3370	>	s.length = n;
3371	>	s.index = i;
3372	>	s.next = stack;
3373	>	stack = s;
3374	>	}
3375	>
3376	>	/**
3377	>	* Possibly pops traversal state.
3378	>	*
3379	>	* @param n length of current table
3380	>	*/
3381	>	private void recoverState(int n) {
3382	>	TableStack<K,V> s; int len;
3383	>	while ((s = stack) != null && (index += (len = s.length)) >= n) {
3384	>	n = len;
3385	>	index = s.index;
3386	>	tab = s.tab;
3387	>	s.tab = null;
3388	>	TableStack<K,V> next = s.next;
3389	>	s.next = spare; // save for reuse
3390	>	stack = next;
3391	>	spare = s;
3392	>	}
3393	>	if (s == null && (index += baseSize) >= n)
3394	>	index = ++baseIndex;
3395	>	}
3396	>	}
3397	>
3398	>	/**
3399	>	* Base of key, value, and entry Iterators. Adds fields to
3400	>	* Traverser to support iterator.remove.
3401	>	*/
3402	>	static class BaseIterator<K,V> extends Traverser<K,V> {
3403	>	final ConcurrentHashMap<K,V> map;
3404	>	Node<K,V> lastReturned;
3405	>	BaseIterator(Node<K,V>[] tab, int size, int index, int limit,
3406	>	ConcurrentHashMap<K,V> map) {
3407	>	super(tab, size, index, limit);
3408	>	this.map = map;
3409		advance();
1098	–	return lastReturned;
3410		}
3411
3412	<	public void remove() {
3413	<	if (lastReturned == null)
3412	>	public final boolean hasNext() { return next != null; }
3413	>	public final boolean hasMoreElements() { return next != null; }
3414	>
3415	>	public final void remove() {
3416	>	Node<K,V> p;
3417	>	if ((p = lastReturned) == null)
3418		throw new IllegalStateException();
1104	–	ConcurrentHashMap.this.remove(lastReturned.key);
3419		lastReturned = null;
3420	+	map.replaceNode(p.key, null, null);
3421		}
3422		}
3423
3424	<	final class KeyIterator
3425	<	extends HashIterator
3426	<	implements Iterator<K>, Enumeration<K>
3427	<	{
3428	<	public K next()        { return super.nextEntry().key; }
3429	<	public K nextElement() { return super.nextEntry().key; }
3424	>	static final class KeyIterator<K,V> extends BaseIterator<K,V>
3425	>	implements Iterator<K>, Enumeration<K> {
3426	>	KeyIterator(Node<K,V>[] tab, int index, int size, int limit,
3427	>	ConcurrentHashMap<K,V> map) {
3428	>	super(tab, index, size, limit, map);
3429	>	}
3430	>
3431	>	public final K next() {
3432	>	Node<K,V> p;
3433	>	if ((p = next) == null)
3434	>	throw new NoSuchElementException();
3435	>	K k = p.key;
3436	>	lastReturned = p;
3437	>	advance();
3438	>	return k;
3439	>	}
3440	>
3441	>	public final K nextElement() { return next(); }
3442	>	}
3443	>
3444	>	static final class ValueIterator<K,V> extends BaseIterator<K,V>
3445	>	implements Iterator<V>, Enumeration<V> {
3446	>	ValueIterator(Node<K,V>[] tab, int index, int size, int limit,
3447	>	ConcurrentHashMap<K,V> map) {
3448	>	super(tab, index, size, limit, map);
3449	>	}
3450	>
3451	>	public final V next() {
3452	>	Node<K,V> p;
3453	>	if ((p = next) == null)
3454	>	throw new NoSuchElementException();
3455	>	V v = p.val;
3456	>	lastReturned = p;
3457	>	advance();
3458	>	return v;
3459	>	}
3460	>
3461	>	public final V nextElement() { return next(); }
3462		}
3463
3464	<	final class ValueIterator
3465	<	extends HashIterator
3466	<	implements Iterator<V>, Enumeration<V>
3467	<	{
3468	<	public V next()        { return super.nextEntry().value; }
3469	<	public V nextElement() { return super.nextEntry().value; }
3464	>	static final class EntryIterator<K,V> extends BaseIterator<K,V>
3465	>	implements Iterator<Map.Entry<K,V>> {
3466	>	EntryIterator(Node<K,V>[] tab, int index, int size, int limit,
3467	>	ConcurrentHashMap<K,V> map) {
3468	>	super(tab, index, size, limit, map);
3469	>	}
3470	>
3471	>	public final Map.Entry<K,V> next() {
3472	>	Node<K,V> p;
3473	>	if ((p = next) == null)
3474	>	throw new NoSuchElementException();
3475	>	K k = p.key;
3476	>	V v = p.val;
3477	>	lastReturned = p;
3478	>	advance();
3479	>	return new MapEntry<K,V>(k, v, map);
3480	>	}
3481		}
3482
3483		/**
3484	<	* Custom Entry class used by EntryIterator.next(), that relays
1127	<	* setValue changes to the underlying map.
3484	>	* Exported Entry for EntryIterator
3485		*/
3486	<	final class WriteThroughEntry
3487	<	extends AbstractMap.SimpleEntry<K,V>
3488	<	{
3489	<	WriteThroughEntry(K k, V v) {
3490	<	super(k,v);
3486	>	static final class MapEntry<K,V> implements Map.Entry<K,V> {
3487	>	final K key; // non-null
3488	>	V val;       // non-null
3489	>	final ConcurrentHashMap<K,V> map;
3490	>	MapEntry(K key, V val, ConcurrentHashMap<K,V> map) {
3491	>	this.key = key;
3492	>	this.val = val;
3493	>	this.map = map;
3494	>	}
3495	>	public K getKey()        { return key; }
3496	>	public V getValue()      { return val; }
3497	>	public int hashCode()    { return key.hashCode() ^ val.hashCode(); }
3498	>	public String toString() {
3499	>	return Helpers.mapEntryToString(key, val);
3500	>	}
3501	>
3502	>	public boolean equals(Object o) {
3503	>	Object k, v; Map.Entry<?,?> e;
3504	>	return ((o instanceof Map.Entry) &&
3505	>	(k = (e = (Map.Entry<?,?>)o).getKey()) != null &&
3506	>	(v = e.getValue()) != null &&
3507	>	(k == key || k.equals(key)) &&
3508	>	(v == val || v.equals(val)));
3509		}
3510
3511		/**
3512	<	* Set our entry's value and write through to the map. The
3513	<	* value to return is somewhat arbitrary here. Since a
3514	<	* WriteThroughEntry does not necessarily track asynchronous
3515	<	* changes, the most recent "previous" value could be
3516	<	* different from what we return (or could even have been
3517	<	* removed in which case the put will re-establish). We do not
1143	<	* and cannot guarantee more.
3512	>	* Sets our entry's value and writes through to the map. The
3513	>	* value to return is somewhat arbitrary here. Since we do not
3514	>	* necessarily track asynchronous changes, the most recent
3515	>	* "previous" value could be different from what we return (or
3516	>	* could even have been removed, in which case the put will
3517	>	* re-establish). We do not and cannot guarantee more.
3518		*/
3519	<	public V setValue(V value) {
3519	>	public V setValue(V value) {
3520		if (value == null) throw new NullPointerException();
3521	<	V v = super.setValue(value);
3522	<	ConcurrentHashMap.this.put(getKey(), value);
3521	>	V v = val;
3522	>	val = value;
3523	>	map.put(key, value);
3524		return v;
3525		}
3526		}
3527
3528	<	final class EntryIterator
3529	<	extends HashIterator
3530	<	implements Iterator<Entry<K,V>>
3531	<	{
3532	<	public Map.Entry<K,V> next() {
3533	<	HashEntry<K,V> e = super.nextEntry();
3534	<	return new WriteThroughEntry(e.key, e.value);
3528	>	static final class KeySpliterator<K,V> extends Traverser<K,V>
3529	>	implements Spliterator<K> {
3530	>	long est;               // size estimate
3531	>	KeySpliterator(Node<K,V>[] tab, int size, int index, int limit,
3532	>	long est) {
3533	>	super(tab, size, index, limit);
3534	>	this.est = est;
3535	>	}
3536	>
3537	>	public Spliterator<K> trySplit() {
3538	>	int i, f, h;
3539	>	return (h = ((i = baseIndex) + (f = baseLimit)) >>> 1) <= i ? null :
3540	>	new KeySpliterator<K,V>(tab, baseSize, baseLimit = h,
3541	>	f, est >>>= 1);
3542	>	}
3543	>
3544	>	public void forEachRemaining(Consumer<? super K> action) {
3545	>	if (action == null) throw new NullPointerException();
3546	>	for (Node<K,V> p; (p = advance()) != null;)
3547	>	action.accept(p.key);
3548	>	}
3549	>
3550	>	public boolean tryAdvance(Consumer<? super K> action) {
3551	>	if (action == null) throw new NullPointerException();
3552	>	Node<K,V> p;
3553	>	if ((p = advance()) == null)
3554	>	return false;
3555	>	action.accept(p.key);
3556	>	return true;
3557	>	}
3558	>
3559	>	public long estimateSize() { return est; }
3560	>
3561	>	public int characteristics() {
3562	>	return Spliterator.DISTINCT | Spliterator.CONCURRENT |
3563	>	Spliterator.NONNULL;
3564		}
3565		}
3566
3567	<	final class KeySet extends AbstractSet<K> {
3568	<	public Iterator<K> iterator() {
3569	<	return new KeyIterator();
3567	>	static final class ValueSpliterator<K,V> extends Traverser<K,V>
3568	>	implements Spliterator<V> {
3569	>	long est;               // size estimate
3570	>	ValueSpliterator(Node<K,V>[] tab, int size, int index, int limit,
3571	>	long est) {
3572	>	super(tab, size, index, limit);
3573	>	this.est = est;
3574	>	}
3575	>
3576	>	public Spliterator<V> trySplit() {
3577	>	int i, f, h;
3578	>	return (h = ((i = baseIndex) + (f = baseLimit)) >>> 1) <= i ? null :
3579	>	new ValueSpliterator<K,V>(tab, baseSize, baseLimit = h,
3580	>	f, est >>>= 1);
3581	>	}
3582	>
3583	>	public void forEachRemaining(Consumer<? super V> action) {
3584	>	if (action == null) throw new NullPointerException();
3585	>	for (Node<K,V> p; (p = advance()) != null;)
3586	>	action.accept(p.val);
3587	>	}
3588	>
3589	>	public boolean tryAdvance(Consumer<? super V> action) {
3590	>	if (action == null) throw new NullPointerException();
3591	>	Node<K,V> p;
3592	>	if ((p = advance()) == null)
3593	>	return false;
3594	>	action.accept(p.val);
3595	>	return true;
3596		}
3597	<	public int size() {
3598	<	return ConcurrentHashMap.this.size();
3597	>
3598	>	public long estimateSize() { return est; }
3599	>
3600	>	public int characteristics() {
3601	>	return Spliterator.CONCURRENT | Spliterator.NONNULL;
3602		}
3603	<	public boolean contains(Object o) {
3604	<	return ConcurrentHashMap.this.containsKey(o);
3603	>	}
3604	>
3605	>	static final class EntrySpliterator<K,V> extends Traverser<K,V>
3606	>	implements Spliterator<Map.Entry<K,V>> {
3607	>	final ConcurrentHashMap<K,V> map; // To export MapEntry
3608	>	long est;               // size estimate
3609	>	EntrySpliterator(Node<K,V>[] tab, int size, int index, int limit,
3610	>	long est, ConcurrentHashMap<K,V> map) {
3611	>	super(tab, size, index, limit);
3612	>	this.map = map;
3613	>	this.est = est;
3614	>	}
3615	>
3616	>	public Spliterator<Map.Entry<K,V>> trySplit() {
3617	>	int i, f, h;
3618	>	return (h = ((i = baseIndex) + (f = baseLimit)) >>> 1) <= i ? null :
3619	>	new EntrySpliterator<K,V>(tab, baseSize, baseLimit = h,
3620	>	f, est >>>= 1, map);
3621	>	}
3622	>
3623	>	public void forEachRemaining(Consumer<? super Map.Entry<K,V>> action) {
3624	>	if (action == null) throw new NullPointerException();
3625	>	for (Node<K,V> p; (p = advance()) != null; )
3626	>	action.accept(new MapEntry<K,V>(p.key, p.val, map));
3627	>	}
3628	>
3629	>	public boolean tryAdvance(Consumer<? super Map.Entry<K,V>> action) {
3630	>	if (action == null) throw new NullPointerException();
3631	>	Node<K,V> p;
3632	>	if ((p = advance()) == null)
3633	>	return false;
3634	>	action.accept(new MapEntry<K,V>(p.key, p.val, map));
3635	>	return true;
3636		}
3637	<	public boolean remove(Object o) {
3638	<	return ConcurrentHashMap.this.remove(o) != null;
3637	>
3638	>	public long estimateSize() { return est; }
3639	>
3640	>	public int characteristics() {
3641	>	return Spliterator.DISTINCT | Spliterator.CONCURRENT |
3642	>	Spliterator.NONNULL;
3643	>	}
3644	>	}
3645	>
3646	>	// Parallel bulk operations
3647	>
3648	>	/**
3649	>	* Computes initial batch value for bulk tasks. The returned value
3650	>	* is approximately exp2 of the number of times (minus one) to
3651	>	* split task by two before executing leaf action. This value is
3652	>	* faster to compute and more convenient to use as a guide to
3653	>	* splitting than is the depth, since it is used while dividing by
3654	>	* two anyway.
3655	>	*/
3656	>	final int batchFor(long b) {
3657	>	long n;
3658	>	if (b == Long.MAX_VALUE || (n = sumCount()) <= 1L || n < b)
3659	>	return 0;
3660	>	int sp = ForkJoinPool.getCommonPoolParallelism() << 2; // slack of 4
3661	>	return (b <= 0L || (n /= b) >= sp) ? sp : (int)n;
3662	>	}
3663	>
3664	>	/**
3665	>	* Performs the given action for each (key, value).
3666	>	*
3667	>	* @param parallelismThreshold the (estimated) number of elements
3668	>	* needed for this operation to be executed in parallel
3669	>	* @param action the action
3670	>	* @since 1.8
3671	>	*/
3672	>	public void forEach(long parallelismThreshold,
3673	>	BiConsumer<? super K,? super V> action) {
3674	>	if (action == null) throw new NullPointerException();
3675	>	new ForEachMappingTask<K,V>
3676	>	(null, batchFor(parallelismThreshold), 0, 0, table,
3677	>	action).invoke();
3678	>	}
3679	>
3680	>	/**
3681	>	* Performs the given action for each non-null transformation
3682	>	* of each (key, value).
3683	>	*
3684	>	* @param parallelismThreshold the (estimated) number of elements
3685	>	* needed for this operation to be executed in parallel
3686	>	* @param transformer a function returning the transformation
3687	>	* for an element, or null if there is no transformation (in
3688	>	* which case the action is not applied)
3689	>	* @param action the action
3690	>	* @param <U> the return type of the transformer
3691	>	* @since 1.8
3692	>	*/
3693	>	public <U> void forEach(long parallelismThreshold,
3694	>	BiFunction<? super K, ? super V, ? extends U> transformer,
3695	>	Consumer<? super U> action) {
3696	>	if (transformer == null || action == null)
3697	>	throw new NullPointerException();
3698	>	new ForEachTransformedMappingTask<K,V,U>
3699	>	(null, batchFor(parallelismThreshold), 0, 0, table,
3700	>	transformer, action).invoke();
3701	>	}
3702	>
3703	>	/**
3704	>	* Returns a non-null result from applying the given search
3705	>	* function on each (key, value), or null if none.  Upon
3706	>	* success, further element processing is suppressed and the
3707	>	* results of any other parallel invocations of the search
3708	>	* function are ignored.
3709	>	*
3710	>	* @param parallelismThreshold the (estimated) number of elements
3711	>	* needed for this operation to be executed in parallel
3712	>	* @param searchFunction a function returning a non-null
3713	>	* result on success, else null
3714	>	* @param <U> the return type of the search function
3715	>	* @return a non-null result from applying the given search
3716	>	* function on each (key, value), or null if none
3717	>	* @since 1.8
3718	>	*/
3719	>	public <U> U search(long parallelismThreshold,
3720	>	BiFunction<? super K, ? super V, ? extends U> searchFunction) {
3721	>	if (searchFunction == null) throw new NullPointerException();
3722	>	return new SearchMappingsTask<K,V,U>
3723	>	(null, batchFor(parallelismThreshold), 0, 0, table,
3724	>	searchFunction, new AtomicReference<U>()).invoke();
3725	>	}
3726	>
3727	>	/**
3728	>	* Returns the result of accumulating the given transformation
3729	>	* of all (key, value) pairs using the given reducer to
3730	>	* combine values, or null if none.
3731	>	*
3732	>	* @param parallelismThreshold the (estimated) number of elements
3733	>	* needed for this operation to be executed in parallel
3734	>	* @param transformer a function returning the transformation
3735	>	* for an element, or null if there is no transformation (in
3736	>	* which case it is not combined)
3737	>	* @param reducer a commutative associative combining function
3738	>	* @param <U> the return type of the transformer
3739	>	* @return the result of accumulating the given transformation
3740	>	* of all (key, value) pairs
3741	>	* @since 1.8
3742	>	*/
3743	>	public <U> U reduce(long parallelismThreshold,
3744	>	BiFunction<? super K, ? super V, ? extends U> transformer,
3745	>	BiFunction<? super U, ? super U, ? extends U> reducer) {
3746	>	if (transformer == null || reducer == null)
3747	>	throw new NullPointerException();
3748	>	return new MapReduceMappingsTask<K,V,U>
3749	>	(null, batchFor(parallelismThreshold), 0, 0, table,
3750	>	null, transformer, reducer).invoke();
3751	>	}
3752	>
3753	>	/**
3754	>	* Returns the result of accumulating the given transformation
3755	>	* of all (key, value) pairs using the given reducer to
3756	>	* combine values, and the given basis as an identity value.
3757	>	*
3758	>	* @param parallelismThreshold the (estimated) number of elements
3759	>	* needed for this operation to be executed in parallel
3760	>	* @param transformer a function returning the transformation
3761	>	* for an element
3762	>	* @param basis the identity (initial default value) for the reduction
3763	>	* @param reducer a commutative associative combining function
3764	>	* @return the result of accumulating the given transformation
3765	>	* of all (key, value) pairs
3766	>	* @since 1.8
3767	>	*/
3768	>	public double reduceToDouble(long parallelismThreshold,
3769	>	ToDoubleBiFunction<? super K, ? super V> transformer,
3770	>	double basis,
3771	>	DoubleBinaryOperator reducer) {
3772	>	if (transformer == null || reducer == null)
3773	>	throw new NullPointerException();
3774	>	return new MapReduceMappingsToDoubleTask<K,V>
3775	>	(null, batchFor(parallelismThreshold), 0, 0, table,
3776	>	null, transformer, basis, reducer).invoke();
3777	>	}
3778	>
3779	>	/**
3780	>	* Returns the result of accumulating the given transformation
3781	>	* of all (key, value) pairs using the given reducer to
3782	>	* combine values, and the given basis as an identity value.
3783	>	*
3784	>	* @param parallelismThreshold the (estimated) number of elements
3785	>	* needed for this operation to be executed in parallel
3786	>	* @param transformer a function returning the transformation
3787	>	* for an element
3788	>	* @param basis the identity (initial default value) for the reduction
3789	>	* @param reducer a commutative associative combining function
3790	>	* @return the result of accumulating the given transformation
3791	>	* of all (key, value) pairs
3792	>	* @since 1.8
3793	>	*/
3794	>	public long reduceToLong(long parallelismThreshold,
3795	>	ToLongBiFunction<? super K, ? super V> transformer,
3796	>	long basis,
3797	>	LongBinaryOperator reducer) {
3798	>	if (transformer == null || reducer == null)
3799	>	throw new NullPointerException();
3800	>	return new MapReduceMappingsToLongTask<K,V>
3801	>	(null, batchFor(parallelismThreshold), 0, 0, table,
3802	>	null, transformer, basis, reducer).invoke();
3803	>	}
3804	>
3805	>	/**
3806	>	* Returns the result of accumulating the given transformation
3807	>	* of all (key, value) pairs using the given reducer to
3808	>	* combine values, and the given basis as an identity value.
3809	>	*
3810	>	* @param parallelismThreshold the (estimated) number of elements
3811	>	* needed for this operation to be executed in parallel
3812	>	* @param transformer a function returning the transformation
3813	>	* for an element
3814	>	* @param basis the identity (initial default value) for the reduction
3815	>	* @param reducer a commutative associative combining function
3816	>	* @return the result of accumulating the given transformation
3817	>	* of all (key, value) pairs
3818	>	* @since 1.8
3819	>	*/
3820	>	public int reduceToInt(long parallelismThreshold,
3821	>	ToIntBiFunction<? super K, ? super V> transformer,
3822	>	int basis,
3823	>	IntBinaryOperator reducer) {
3824	>	if (transformer == null || reducer == null)
3825	>	throw new NullPointerException();
3826	>	return new MapReduceMappingsToIntTask<K,V>
3827	>	(null, batchFor(parallelismThreshold), 0, 0, table,
3828	>	null, transformer, basis, reducer).invoke();
3829	>	}
3830	>
3831	>	/**
3832	>	* Performs the given action for each key.
3833	>	*
3834	>	* @param parallelismThreshold the (estimated) number of elements
3835	>	* needed for this operation to be executed in parallel
3836	>	* @param action the action
3837	>	* @since 1.8
3838	>	*/
3839	>	public void forEachKey(long parallelismThreshold,
3840	>	Consumer<? super K> action) {
3841	>	if (action == null) throw new NullPointerException();
3842	>	new ForEachKeyTask<K,V>
3843	>	(null, batchFor(parallelismThreshold), 0, 0, table,
3844	>	action).invoke();
3845	>	}
3846	>
3847	>	/**
3848	>	* Performs the given action for each non-null transformation
3849	>	* of each key.
3850	>	*
3851	>	* @param parallelismThreshold the (estimated) number of elements
3852	>	* needed for this operation to be executed in parallel
3853	>	* @param transformer a function returning the transformation
3854	>	* for an element, or null if there is no transformation (in
3855	>	* which case the action is not applied)
3856	>	* @param action the action
3857	>	* @param <U> the return type of the transformer
3858	>	* @since 1.8
3859	>	*/
3860	>	public <U> void forEachKey(long parallelismThreshold,
3861	>	Function<? super K, ? extends U> transformer,
3862	>	Consumer<? super U> action) {
3863	>	if (transformer == null || action == null)
3864	>	throw new NullPointerException();
3865	>	new ForEachTransformedKeyTask<K,V,U>
3866	>	(null, batchFor(parallelismThreshold), 0, 0, table,
3867	>	transformer, action).invoke();
3868	>	}
3869	>
3870	>	/**
3871	>	* Returns a non-null result from applying the given search
3872	>	* function on each key, or null if none. Upon success,
3873	>	* further element processing is suppressed and the results of
3874	>	* any other parallel invocations of the search function are
3875	>	* ignored.
3876	>	*
3877	>	* @param parallelismThreshold the (estimated) number of elements
3878	>	* needed for this operation to be executed in parallel
3879	>	* @param searchFunction a function returning a non-null
3880	>	* result on success, else null
3881	>	* @param <U> the return type of the search function
3882	>	* @return a non-null result from applying the given search
3883	>	* function on each key, or null if none
3884	>	* @since 1.8
3885	>	*/
3886	>	public <U> U searchKeys(long parallelismThreshold,
3887	>	Function<? super K, ? extends U> searchFunction) {
3888	>	if (searchFunction == null) throw new NullPointerException();
3889	>	return new SearchKeysTask<K,V,U>
3890	>	(null, batchFor(parallelismThreshold), 0, 0, table,
3891	>	searchFunction, new AtomicReference<U>()).invoke();
3892	>	}
3893	>
3894	>	/**
3895	>	* Returns the result of accumulating all keys using the given
3896	>	* reducer to combine values, or null if none.
3897	>	*
3898	>	* @param parallelismThreshold the (estimated) number of elements
3899	>	* needed for this operation to be executed in parallel
3900	>	* @param reducer a commutative associative combining function
3901	>	* @return the result of accumulating all keys using the given
3902	>	* reducer to combine values, or null if none
3903	>	* @since 1.8
3904	>	*/
3905	>	public K reduceKeys(long parallelismThreshold,
3906	>	BiFunction<? super K, ? super K, ? extends K> reducer) {
3907	>	if (reducer == null) throw new NullPointerException();
3908	>	return new ReduceKeysTask<K,V>
3909	>	(null, batchFor(parallelismThreshold), 0, 0, table,
3910	>	null, reducer).invoke();
3911	>	}
3912	>
3913	>	/**
3914	>	* Returns the result of accumulating the given transformation
3915	>	* of all keys using the given reducer to combine values, or
3916	>	* null if none.
3917	>	*
3918	>	* @param parallelismThreshold the (estimated) number of elements
3919	>	* needed for this operation to be executed in parallel
3920	>	* @param transformer a function returning the transformation
3921	>	* for an element, or null if there is no transformation (in
3922	>	* which case it is not combined)
3923	>	* @param reducer a commutative associative combining function
3924	>	* @param <U> the return type of the transformer
3925	>	* @return the result of accumulating the given transformation
3926	>	* of all keys
3927	>	* @since 1.8
3928	>	*/
3929	>	public <U> U reduceKeys(long parallelismThreshold,
3930	>	Function<? super K, ? extends U> transformer,
3931	>	BiFunction<? super U, ? super U, ? extends U> reducer) {
3932	>	if (transformer == null || reducer == null)
3933	>	throw new NullPointerException();
3934	>	return new MapReduceKeysTask<K,V,U>
3935	>	(null, batchFor(parallelismThreshold), 0, 0, table,
3936	>	null, transformer, reducer).invoke();
3937	>	}
3938	>
3939	>	/**
3940	>	* Returns the result of accumulating the given transformation
3941	>	* of all keys using the given reducer to combine values, and
3942	>	* the given basis as an identity value.
3943	>	*
3944	>	* @param parallelismThreshold the (estimated) number of elements
3945	>	* needed for this operation to be executed in parallel
3946	>	* @param transformer a function returning the transformation
3947	>	* for an element
3948	>	* @param basis the identity (initial default value) for the reduction
3949	>	* @param reducer a commutative associative combining function
3950	>	* @return the result of accumulating the given transformation
3951	>	* of all keys
3952	>	* @since 1.8
3953	>	*/
3954	>	public double reduceKeysToDouble(long parallelismThreshold,
3955	>	ToDoubleFunction<? super K> transformer,
3956	>	double basis,
3957	>	DoubleBinaryOperator reducer) {
3958	>	if (transformer == null || reducer == null)
3959	>	throw new NullPointerException();
3960	>	return new MapReduceKeysToDoubleTask<K,V>
3961	>	(null, batchFor(parallelismThreshold), 0, 0, table,
3962	>	null, transformer, basis, reducer).invoke();
3963	>	}
3964	>
3965	>	/**
3966	>	* Returns the result of accumulating the given transformation
3967	>	* of all keys using the given reducer to combine values, and
3968	>	* the given basis as an identity value.
3969	>	*
3970	>	* @param parallelismThreshold the (estimated) number of elements
3971	>	* needed for this operation to be executed in parallel
3972	>	* @param transformer a function returning the transformation
3973	>	* for an element
3974	>	* @param basis the identity (initial default value) for the reduction
3975	>	* @param reducer a commutative associative combining function
3976	>	* @return the result of accumulating the given transformation
3977	>	* of all keys
3978	>	* @since 1.8
3979	>	*/
3980	>	public long reduceKeysToLong(long parallelismThreshold,
3981	>	ToLongFunction<? super K> transformer,
3982	>	long basis,
3983	>	LongBinaryOperator reducer) {
3984	>	if (transformer == null || reducer == null)
3985	>	throw new NullPointerException();
3986	>	return new MapReduceKeysToLongTask<K,V>
3987	>	(null, batchFor(parallelismThreshold), 0, 0, table,
3988	>	null, transformer, basis, reducer).invoke();
3989	>	}
3990	>
3991	>	/**
3992	>	* Returns the result of accumulating the given transformation
3993	>	* of all keys using the given reducer to combine values, and
3994	>	* the given basis as an identity value.
3995	>	*
3996	>	* @param parallelismThreshold the (estimated) number of elements
3997	>	* needed for this operation to be executed in parallel
3998	>	* @param transformer a function returning the transformation
3999	>	* for an element
4000	>	* @param basis the identity (initial default value) for the reduction
4001	>	* @param reducer a commutative associative combining function
4002	>	* @return the result of accumulating the given transformation
4003	>	* of all keys
4004	>	* @since 1.8
4005	>	*/
4006	>	public int reduceKeysToInt(long parallelismThreshold,
4007	>	ToIntFunction<? super K> transformer,
4008	>	int basis,
4009	>	IntBinaryOperator reducer) {
4010	>	if (transformer == null || reducer == null)
4011	>	throw new NullPointerException();
4012	>	return new MapReduceKeysToIntTask<K,V>
4013	>	(null, batchFor(parallelismThreshold), 0, 0, table,
4014	>	null, transformer, basis, reducer).invoke();
4015	>	}
4016	>
4017	>	/**
4018	>	* Performs the given action for each value.
4019	>	*
4020	>	* @param parallelismThreshold the (estimated) number of elements
4021	>	* needed for this operation to be executed in parallel
4022	>	* @param action the action
4023	>	* @since 1.8
4024	>	*/
4025	>	public void forEachValue(long parallelismThreshold,
4026	>	Consumer<? super V> action) {
4027	>	if (action == null)
4028	>	throw new NullPointerException();
4029	>	new ForEachValueTask<K,V>
4030	>	(null, batchFor(parallelismThreshold), 0, 0, table,
4031	>	action).invoke();
4032	>	}
4033	>
4034	>	/**
4035	>	* Performs the given action for each non-null transformation
4036	>	* of each value.
4037	>	*
4038	>	* @param parallelismThreshold the (estimated) number of elements
4039	>	* needed for this operation to be executed in parallel
4040	>	* @param transformer a function returning the transformation
4041	>	* for an element, or null if there is no transformation (in
4042	>	* which case the action is not applied)
4043	>	* @param action the action
4044	>	* @param <U> the return type of the transformer
4045	>	* @since 1.8
4046	>	*/
4047	>	public <U> void forEachValue(long parallelismThreshold,
4048	>	Function<? super V, ? extends U> transformer,
4049	>	Consumer<? super U> action) {
4050	>	if (transformer == null || action == null)
4051	>	throw new NullPointerException();
4052	>	new ForEachTransformedValueTask<K,V,U>
4053	>	(null, batchFor(parallelismThreshold), 0, 0, table,
4054	>	transformer, action).invoke();
4055	>	}
4056	>
4057	>	/**
4058	>	* Returns a non-null result from applying the given search
4059	>	* function on each value, or null if none.  Upon success,
4060	>	* further element processing is suppressed and the results of
4061	>	* any other parallel invocations of the search function are
4062	>	* ignored.
4063	>	*
4064	>	* @param parallelismThreshold the (estimated) number of elements
4065	>	* needed for this operation to be executed in parallel
4066	>	* @param searchFunction a function returning a non-null
4067	>	* result on success, else null
4068	>	* @param <U> the return type of the search function
4069	>	* @return a non-null result from applying the given search
4070	>	* function on each value, or null if none
4071	>	* @since 1.8
4072	>	*/
4073	>	public <U> U searchValues(long parallelismThreshold,
4074	>	Function<? super V, ? extends U> searchFunction) {
4075	>	if (searchFunction == null) throw new NullPointerException();
4076	>	return new SearchValuesTask<K,V,U>
4077	>	(null, batchFor(parallelismThreshold), 0, 0, table,
4078	>	searchFunction, new AtomicReference<U>()).invoke();
4079	>	}
4080	>
4081	>	/**
4082	>	* Returns the result of accumulating all values using the
4083	>	* given reducer to combine values, or null if none.
4084	>	*
4085	>	* @param parallelismThreshold the (estimated) number of elements
4086	>	* needed for this operation to be executed in parallel
4087	>	* @param reducer a commutative associative combining function
4088	>	* @return the result of accumulating all values
4089	>	* @since 1.8
4090	>	*/
4091	>	public V reduceValues(long parallelismThreshold,
4092	>	BiFunction<? super V, ? super V, ? extends V> reducer) {
4093	>	if (reducer == null) throw new NullPointerException();
4094	>	return new ReduceValuesTask<K,V>
4095	>	(null, batchFor(parallelismThreshold), 0, 0, table,
4096	>	null, reducer).invoke();
4097	>	}
4098	>
4099	>	/**
4100	>	* Returns the result of accumulating the given transformation
4101	>	* of all values using the given reducer to combine values, or
4102	>	* null if none.
4103	>	*
4104	>	* @param parallelismThreshold the (estimated) number of elements
4105	>	* needed for this operation to be executed in parallel
4106	>	* @param transformer a function returning the transformation
4107	>	* for an element, or null if there is no transformation (in
4108	>	* which case it is not combined)
4109	>	* @param reducer a commutative associative combining function
4110	>	* @param <U> the return type of the transformer
4111	>	* @return the result of accumulating the given transformation
4112	>	* of all values
4113	>	* @since 1.8
4114	>	*/
4115	>	public <U> U reduceValues(long parallelismThreshold,
4116	>	Function<? super V, ? extends U> transformer,
4117	>	BiFunction<? super U, ? super U, ? extends U> reducer) {
4118	>	if (transformer == null || reducer == null)
4119	>	throw new NullPointerException();
4120	>	return new MapReduceValuesTask<K,V,U>
4121	>	(null, batchFor(parallelismThreshold), 0, 0, table,
4122	>	null, transformer, reducer).invoke();
4123	>	}
4124	>
4125	>	/**
4126	>	* Returns the result of accumulating the given transformation
4127	>	* of all values using the given reducer to combine values,
4128	>	* and the given basis as an identity value.
4129	>	*
4130	>	* @param parallelismThreshold the (estimated) number of elements
4131	>	* needed for this operation to be executed in parallel
4132	>	* @param transformer a function returning the transformation
4133	>	* for an element
4134	>	* @param basis the identity (initial default value) for the reduction
4135	>	* @param reducer a commutative associative combining function
4136	>	* @return the result of accumulating the given transformation
4137	>	* of all values
4138	>	* @since 1.8
4139	>	*/
4140	>	public double reduceValuesToDouble(long parallelismThreshold,
4141	>	ToDoubleFunction<? super V> transformer,
4142	>	double basis,
4143	>	DoubleBinaryOperator reducer) {
4144	>	if (transformer == null || reducer == null)
4145	>	throw new NullPointerException();
4146	>	return new MapReduceValuesToDoubleTask<K,V>
4147	>	(null, batchFor(parallelismThreshold), 0, 0, table,
4148	>	null, transformer, basis, reducer).invoke();
4149	>	}
4150	>
4151	>	/**
4152	>	* Returns the result of accumulating the given transformation
4153	>	* of all values using the given reducer to combine values,
4154	>	* and the given basis as an identity value.
4155	>	*
4156	>	* @param parallelismThreshold the (estimated) number of elements
4157	>	* needed for this operation to be executed in parallel
4158	>	* @param transformer a function returning the transformation
4159	>	* for an element
4160	>	* @param basis the identity (initial default value) for the reduction
4161	>	* @param reducer a commutative associative combining function
4162	>	* @return the result of accumulating the given transformation
4163	>	* of all values
4164	>	* @since 1.8
4165	>	*/
4166	>	public long reduceValuesToLong(long parallelismThreshold,
4167	>	ToLongFunction<? super V> transformer,
4168	>	long basis,
4169	>	LongBinaryOperator reducer) {
4170	>	if (transformer == null || reducer == null)
4171	>	throw new NullPointerException();
4172	>	return new MapReduceValuesToLongTask<K,V>
4173	>	(null, batchFor(parallelismThreshold), 0, 0, table,
4174	>	null, transformer, basis, reducer).invoke();
4175	>	}
4176	>
4177	>	/**
4178	>	* Returns the result of accumulating the given transformation
4179	>	* of all values using the given reducer to combine values,
4180	>	* and the given basis as an identity value.
4181	>	*
4182	>	* @param parallelismThreshold the (estimated) number of elements
4183	>	* needed for this operation to be executed in parallel
4184	>	* @param transformer a function returning the transformation
4185	>	* for an element
4186	>	* @param basis the identity (initial default value) for the reduction
4187	>	* @param reducer a commutative associative combining function
4188	>	* @return the result of accumulating the given transformation
4189	>	* of all values
4190	>	* @since 1.8
4191	>	*/
4192	>	public int reduceValuesToInt(long parallelismThreshold,
4193	>	ToIntFunction<? super V> transformer,
4194	>	int basis,
4195	>	IntBinaryOperator reducer) {
4196	>	if (transformer == null || reducer == null)
4197	>	throw new NullPointerException();
4198	>	return new MapReduceValuesToIntTask<K,V>
4199	>	(null, batchFor(parallelismThreshold), 0, 0, table,
4200	>	null, transformer, basis, reducer).invoke();
4201	>	}
4202	>
4203	>	/**
4204	>	* Performs the given action for each entry.
4205	>	*
4206	>	* @param parallelismThreshold the (estimated) number of elements
4207	>	* needed for this operation to be executed in parallel
4208	>	* @param action the action
4209	>	* @since 1.8
4210	>	*/
4211	>	public void forEachEntry(long parallelismThreshold,
4212	>	Consumer<? super Map.Entry<K,V>> action) {
4213	>	if (action == null) throw new NullPointerException();
4214	>	new ForEachEntryTask<K,V>(null, batchFor(parallelismThreshold), 0, 0, table,
4215	>	action).invoke();
4216	>	}
4217	>
4218	>	/**
4219	>	* Performs the given action for each non-null transformation
4220	>	* of each entry.
4221	>	*
4222	>	* @param parallelismThreshold the (estimated) number of elements
4223	>	* needed for this operation to be executed in parallel
4224	>	* @param transformer a function returning the transformation
4225	>	* for an element, or null if there is no transformation (in
4226	>	* which case the action is not applied)
4227	>	* @param action the action
4228	>	* @param <U> the return type of the transformer
4229	>	* @since 1.8
4230	>	*/
4231	>	public <U> void forEachEntry(long parallelismThreshold,
4232	>	Function<Map.Entry<K,V>, ? extends U> transformer,
4233	>	Consumer<? super U> action) {
4234	>	if (transformer == null || action == null)
4235	>	throw new NullPointerException();
4236	>	new ForEachTransformedEntryTask<K,V,U>
4237	>	(null, batchFor(parallelismThreshold), 0, 0, table,
4238	>	transformer, action).invoke();
4239	>	}
4240	>
4241	>	/**
4242	>	* Returns a non-null result from applying the given search
4243	>	* function on each entry, or null if none.  Upon success,
4244	>	* further element processing is suppressed and the results of
4245	>	* any other parallel invocations of the search function are
4246	>	* ignored.
4247	>	*
4248	>	* @param parallelismThreshold the (estimated) number of elements
4249	>	* needed for this operation to be executed in parallel
4250	>	* @param searchFunction a function returning a non-null
4251	>	* result on success, else null
4252	>	* @param <U> the return type of the search function
4253	>	* @return a non-null result from applying the given search
4254	>	* function on each entry, or null if none
4255	>	* @since 1.8
4256	>	*/
4257	>	public <U> U searchEntries(long parallelismThreshold,
4258	>	Function<Map.Entry<K,V>, ? extends U> searchFunction) {
4259	>	if (searchFunction == null) throw new NullPointerException();
4260	>	return new SearchEntriesTask<K,V,U>
4261	>	(null, batchFor(parallelismThreshold), 0, 0, table,
4262	>	searchFunction, new AtomicReference<U>()).invoke();
4263	>	}
4264	>
4265	>	/**
4266	>	* Returns the result of accumulating all entries using the
4267	>	* given reducer to combine values, or null if none.
4268	>	*
4269	>	* @param parallelismThreshold the (estimated) number of elements
4270	>	* needed for this operation to be executed in parallel
4271	>	* @param reducer a commutative associative combining function
4272	>	* @return the result of accumulating all entries
4273	>	* @since 1.8
4274	>	*/
4275	>	public Map.Entry<K,V> reduceEntries(long parallelismThreshold,
4276	>	BiFunction<Map.Entry<K,V>, Map.Entry<K,V>, ? extends Map.Entry<K,V>> reducer) {
4277	>	if (reducer == null) throw new NullPointerException();
4278	>	return new ReduceEntriesTask<K,V>
4279	>	(null, batchFor(parallelismThreshold), 0, 0, table,
4280	>	null, reducer).invoke();
4281	>	}
4282	>
4283	>	/**
4284	>	* Returns the result of accumulating the given transformation
4285	>	* of all entries using the given reducer to combine values,
4286	>	* or null if none.
4287	>	*
4288	>	* @param parallelismThreshold the (estimated) number of elements
4289	>	* needed for this operation to be executed in parallel
4290	>	* @param transformer a function returning the transformation
4291	>	* for an element, or null if there is no transformation (in
4292	>	* which case it is not combined)
4293	>	* @param reducer a commutative associative combining function
4294	>	* @param <U> the return type of the transformer
4295	>	* @return the result of accumulating the given transformation
4296	>	* of all entries
4297	>	* @since 1.8
4298	>	*/
4299	>	public <U> U reduceEntries(long parallelismThreshold,
4300	>	Function<Map.Entry<K,V>, ? extends U> transformer,
4301	>	BiFunction<? super U, ? super U, ? extends U> reducer) {
4302	>	if (transformer == null || reducer == null)
4303	>	throw new NullPointerException();
4304	>	return new MapReduceEntriesTask<K,V,U>
4305	>	(null, batchFor(parallelismThreshold), 0, 0, table,
4306	>	null, transformer, reducer).invoke();
4307	>	}
4308	>
4309	>	/**
4310	>	* Returns the result of accumulating the given transformation
4311	>	* of all entries using the given reducer to combine values,
4312	>	* and the given basis as an identity value.
4313	>	*
4314	>	* @param parallelismThreshold the (estimated) number of elements
4315	>	* needed for this operation to be executed in parallel
4316	>	* @param transformer a function returning the transformation
4317	>	* for an element
4318	>	* @param basis the identity (initial default value) for the reduction
4319	>	* @param reducer a commutative associative combining function
4320	>	* @return the result of accumulating the given transformation
4321	>	* of all entries
4322	>	* @since 1.8
4323	>	*/
4324	>	public double reduceEntriesToDouble(long parallelismThreshold,
4325	>	ToDoubleFunction<Map.Entry<K,V>> transformer,
4326	>	double basis,
4327	>	DoubleBinaryOperator reducer) {
4328	>	if (transformer == null || reducer == null)
4329	>	throw new NullPointerException();
4330	>	return new MapReduceEntriesToDoubleTask<K,V>
4331	>	(null, batchFor(parallelismThreshold), 0, 0, table,
4332	>	null, transformer, basis, reducer).invoke();
4333	>	}
4334	>
4335	>	/**
4336	>	* Returns the result of accumulating the given transformation
4337	>	* of all entries using the given reducer to combine values,
4338	>	* and the given basis as an identity value.
4339	>	*
4340	>	* @param parallelismThreshold the (estimated) number of elements
4341	>	* needed for this operation to be executed in parallel
4342	>	* @param transformer a function returning the transformation
4343	>	* for an element
4344	>	* @param basis the identity (initial default value) for the reduction
4345	>	* @param reducer a commutative associative combining function
4346	>	* @return the result of accumulating the given transformation
4347	>	* of all entries
4348	>	* @since 1.8
4349	>	*/
4350	>	public long reduceEntriesToLong(long parallelismThreshold,
4351	>	ToLongFunction<Map.Entry<K,V>> transformer,
4352	>	long basis,
4353	>	LongBinaryOperator reducer) {
4354	>	if (transformer == null || reducer == null)
4355	>	throw new NullPointerException();
4356	>	return new MapReduceEntriesToLongTask<K,V>
4357	>	(null, batchFor(parallelismThreshold), 0, 0, table,
4358	>	null, transformer, basis, reducer).invoke();
4359	>	}
4360	>
4361	>	/**
4362	>	* Returns the result of accumulating the given transformation
4363	>	* of all entries using the given reducer to combine values,
4364	>	* and the given basis as an identity value.
4365	>	*
4366	>	* @param parallelismThreshold the (estimated) number of elements
4367	>	* needed for this operation to be executed in parallel
4368	>	* @param transformer a function returning the transformation
4369	>	* for an element
4370	>	* @param basis the identity (initial default value) for the reduction
4371	>	* @param reducer a commutative associative combining function
4372	>	* @return the result of accumulating the given transformation
4373	>	* of all entries
4374	>	* @since 1.8
4375	>	*/
4376	>	public int reduceEntriesToInt(long parallelismThreshold,
4377	>	ToIntFunction<Map.Entry<K,V>> transformer,
4378	>	int basis,
4379	>	IntBinaryOperator reducer) {
4380	>	if (transformer == null || reducer == null)
4381	>	throw new NullPointerException();
4382	>	return new MapReduceEntriesToIntTask<K,V>
4383	>	(null, batchFor(parallelismThreshold), 0, 0, table,
4384	>	null, transformer, basis, reducer).invoke();
4385	>	}
4386	>
4387	>
4388	>	/* ----------------Views -------------- */
4389	>
4390	>	/**
4391	>	* Base class for views.
4392	>	*/
4393	>	abstract static class CollectionView<K,V,E>
4394	>	implements Collection<E>, java.io.Serializable {
4395	>	private static final long serialVersionUID = 7249069246763182397L;
4396	>	final ConcurrentHashMap<K,V> map;
4397	>	CollectionView(ConcurrentHashMap<K,V> map)  { this.map = map; }
4398	>
4399	>	/**
4400	>	* Returns the map backing this view.
4401	>	*
4402	>	* @return the map backing this view
4403	>	*/
4404	>	public ConcurrentHashMap<K,V> getMap() { return map; }
4405	>
4406	>	/**
4407	>	* Removes all of the elements from this view, by removing all
4408	>	* the mappings from the map backing this view.
4409	>	*/
4410	>	public final void clear()      { map.clear(); }
4411	>	public final int size()        { return map.size(); }
4412	>	public final boolean isEmpty() { return map.isEmpty(); }
4413	>
4414	>	// implementations below rely on concrete classes supplying these
4415	>	// abstract methods
4416	>	/**
4417	>	* Returns an iterator over the elements in this collection.
4418	>	*
4419	>	* <p>The returned iterator is
4420	>	* <a href="package-summary.html#Weakly"><i>weakly consistent</i></a>.
4421	>	*
4422	>	* @return an iterator over the elements in this collection
4423	>	*/
4424	>	public abstract Iterator<E> iterator();
4425	>	public abstract boolean contains(Object o);
4426	>	public abstract boolean remove(Object o);
4427	>
4428	>	private static final String oomeMsg = "Required array size too large";
4429	>
4430	>	public final Object[] toArray() {
4431	>	long sz = map.mappingCount();
4432	>	if (sz > MAX_ARRAY_SIZE)
4433	>	throw new OutOfMemoryError(oomeMsg);
4434	>	int n = (int)sz;
4435	>	Object[] r = new Object[n];
4436	>	int i = 0;
4437	>	for (E e : this) {
4438	>	if (i == n) {
4439	>	if (n >= MAX_ARRAY_SIZE)
4440	>	throw new OutOfMemoryError(oomeMsg);
4441	>	if (n >= MAX_ARRAY_SIZE - (MAX_ARRAY_SIZE >>> 1) - 1)
4442	>	n = MAX_ARRAY_SIZE;
4443	>	else
4444	>	n += (n >>> 1) + 1;
4445	>	r = Arrays.copyOf(r, n);
4446	>	}
4447	>	r[i++] = e;
4448	>	}
4449	>	return (i == n) ? r : Arrays.copyOf(r, i);
4450		}
4451	<	public void clear() {
4452	<	ConcurrentHashMap.this.clear();
4451	>
4452	>	@SuppressWarnings("unchecked")
4453	>	public final <T> T[] toArray(T[] a) {
4454	>	long sz = map.mappingCount();
4455	>	if (sz > MAX_ARRAY_SIZE)
4456	>	throw new OutOfMemoryError(oomeMsg);
4457	>	int m = (int)sz;
4458	>	T[] r = (a.length >= m) ? a :
4459	>	(T[])java.lang.reflect.Array
4460	>	.newInstance(a.getClass().getComponentType(), m);
4461	>	int n = r.length;
4462	>	int i = 0;
4463	>	for (E e : this) {
4464	>	if (i == n) {
4465	>	if (n >= MAX_ARRAY_SIZE)
4466	>	throw new OutOfMemoryError(oomeMsg);
4467	>	if (n >= MAX_ARRAY_SIZE - (MAX_ARRAY_SIZE >>> 1) - 1)
4468	>	n = MAX_ARRAY_SIZE;
4469	>	else
4470	>	n += (n >>> 1) + 1;
4471	>	r = Arrays.copyOf(r, n);
4472	>	}
4473	>	r[i++] = (T)e;
4474	>	}
4475	>	if (a == r && i < n) {
4476	>	r[i] = null; // null-terminate
4477	>	return r;
4478	>	}
4479	>	return (i == n) ? r : Arrays.copyOf(r, i);
4480		}
4481	+
4482	+	/**
4483	+	* Returns a string representation of this collection.
4484	+	* The string representation consists of the string representations
4485	+	* of the collection's elements in the order they are returned by
4486	+	* its iterator, enclosed in square brackets ({@code "[]"}).
4487	+	* Adjacent elements are separated by the characters {@code ", "}
4488	+	* (comma and space).  Elements are converted to strings as by
4489	+	* {@link String#valueOf(Object)}.
4490	+	*
4491	+	* @return a string representation of this collection
4492	+	*/
4493	+	public final String toString() {
4494	+	StringBuilder sb = new StringBuilder();
4495	+	sb.append('[');
4496	+	Iterator<E> it = iterator();
4497	+	if (it.hasNext()) {
4498	+	for (;;) {
4499	+	Object e = it.next();
4500	+	sb.append(e == this ? "(this Collection)" : e);
4501	+	if (!it.hasNext())
4502	+	break;
4503	+	sb.append(',').append(' ');
4504	+	}
4505	+	}
4506	+	return sb.append(']').toString();
4507	+	}
4508	+
4509	+	public final boolean containsAll(Collection<?> c) {
4510	+	if (c != this) {
4511	+	for (Object e : c) {
4512	+	if (e == null || !contains(e))
4513	+	return false;
4514	+	}
4515	+	}
4516	+	return true;
4517	+	}
4518	+
4519	+	public final boolean removeAll(Collection<?> c) {
4520	+	if (c == null) throw new NullPointerException();
4521	+	boolean modified = false;
4522	+	for (Iterator<E> it = iterator(); it.hasNext();) {
4523	+	if (c.contains(it.next())) {
4524	+	it.remove();
4525	+	modified = true;
4526	+	}
4527	+	}
4528	+	return modified;
4529	+	}
4530	+
4531	+	public final boolean retainAll(Collection<?> c) {
4532	+	if (c == null) throw new NullPointerException();
4533	+	boolean modified = false;
4534	+	for (Iterator<E> it = iterator(); it.hasNext();) {
4535	+	if (!c.contains(it.next())) {
4536	+	it.remove();
4537	+	modified = true;
4538	+	}
4539	+	}
4540	+	return modified;
4541	+	}
4542	+
4543		}
4544
4545	<	final class Values extends AbstractCollection<V> {
4546	<	public Iterator<V> iterator() {
4547	<	return new ValueIterator();
4545	>	/**
4546	>	* A view of a ConcurrentHashMap as a {@link Set} of keys, in
4547	>	* which additions may optionally be enabled by mapping to a
4548	>	* common value.  This class cannot be directly instantiated.
4549	>	* See {@link #keySet() keySet()},
4550	>	* {@link #keySet(Object) keySet(V)},
4551	>	* {@link #newKeySet() newKeySet()},
4552	>	* {@link #newKeySet(int) newKeySet(int)}.
4553	>	*
4554	>	* @since 1.8
4555	>	*/
4556	>	public static class KeySetView<K,V> extends CollectionView<K,V,K>
4557	>	implements Set<K>, java.io.Serializable {
4558	>	private static final long serialVersionUID = 7249069246763182397L;
4559	>	private final V value;
4560	>	KeySetView(ConcurrentHashMap<K,V> map, V value) {  // non-public
4561	>	super(map);
4562	>	this.value = value;
4563		}
4564	<	public int size() {
4565	<	return ConcurrentHashMap.this.size();
4564	>
4565	>	/**
4566	>	* Returns the default mapped value for additions,
4567	>	* or {@code null} if additions are not supported.
4568	>	*
4569	>	* @return the default mapped value for additions, or {@code null}
4570	>	* if not supported
4571	>	*/
4572	>	public V getMappedValue() { return value; }
4573	>
4574	>	/**
4575	>	* {@inheritDoc}
4576	>	* @throws NullPointerException if the specified key is null
4577	>	*/
4578	>	public boolean contains(Object o) { return map.containsKey(o); }
4579	>
4580	>	/**
4581	>	* Removes the key from this map view, by removing the key (and its
4582	>	* corresponding value) from the backing map.  This method does
4583	>	* nothing if the key is not in the map.
4584	>	*
4585	>	* @param  o the key to be removed from the backing map
4586	>	* @return {@code true} if the backing map contained the specified key
4587	>	* @throws NullPointerException if the specified key is null
4588	>	*/
4589	>	public boolean remove(Object o) { return map.remove(o) != null; }
4590	>
4591	>	/**
4592	>	* @return an iterator over the keys of the backing map
4593	>	*/
4594	>	public Iterator<K> iterator() {
4595	>	Node<K,V>[] t;
4596	>	ConcurrentHashMap<K,V> m = map;
4597	>	int f = (t = m.table) == null ? 0 : t.length;
4598	>	return new KeyIterator<K,V>(t, f, 0, f, m);
4599		}
4600	<	public boolean contains(Object o) {
4601	<	return ConcurrentHashMap.this.containsValue(o);
4600	>
4601	>	/**
4602	>	* Adds the specified key to this set view by mapping the key to
4603	>	* the default mapped value in the backing map, if defined.
4604	>	*
4605	>	* @param e key to be added
4606	>	* @return {@code true} if this set changed as a result of the call
4607	>	* @throws NullPointerException if the specified key is null
4608	>	* @throws UnsupportedOperationException if no default mapped value
4609	>	* for additions was provided
4610	>	*/
4611	>	public boolean add(K e) {
4612	>	V v;
4613	>	if ((v = value) == null)
4614	>	throw new UnsupportedOperationException();
4615	>	return map.putVal(e, v, true) == null;
4616	>	}
4617	>
4618	>	/**
4619	>	* Adds all of the elements in the specified collection to this set,
4620	>	* as if by calling {@link #add} on each one.
4621	>	*
4622	>	* @param c the elements to be inserted into this set
4623	>	* @return {@code true} if this set changed as a result of the call
4624	>	* @throws NullPointerException if the collection or any of its
4625	>	* elements are {@code null}
4626	>	* @throws UnsupportedOperationException if no default mapped value
4627	>	* for additions was provided
4628	>	*/
4629	>	public boolean addAll(Collection<? extends K> c) {
4630	>	boolean added = false;
4631	>	V v;
4632	>	if ((v = value) == null)
4633	>	throw new UnsupportedOperationException();
4634	>	for (K e : c) {
4635	>	if (map.putVal(e, v, true) == null)
4636	>	added = true;
4637	>	}
4638	>	return added;
4639		}
4640	<	public void clear() {
4641	<	ConcurrentHashMap.this.clear();
4640	>
4641	>	public int hashCode() {
4642	>	int h = 0;
4643	>	for (K e : this)
4644	>	h += e.hashCode();
4645	>	return h;
4646	>	}
4647	>
4648	>	public boolean equals(Object o) {
4649	>	Set<?> c;
4650	>	return ((o instanceof Set) &&
4651	>	((c = (Set<?>)o) == this ||
4652	>	(containsAll(c) && c.containsAll(this))));
4653	>	}
4654	>
4655	>	public Spliterator<K> spliterator() {
4656	>	Node<K,V>[] t;
4657	>	ConcurrentHashMap<K,V> m = map;
4658	>	long n = m.sumCount();
4659	>	int f = (t = m.table) == null ? 0 : t.length;
4660	>	return new KeySpliterator<K,V>(t, f, 0, f, n < 0L ? 0L : n);
4661	>	}
4662	>
4663	>	public void forEach(Consumer<? super K> action) {
4664	>	if (action == null) throw new NullPointerException();
4665	>	Node<K,V>[] t;
4666	>	if ((t = map.table) != null) {
4667	>	Traverser<K,V> it = new Traverser<K,V>(t, t.length, 0, t.length);
4668	>	for (Node<K,V> p; (p = it.advance()) != null; )
4669	>	action.accept(p.key);
4670	>	}
4671		}
4672		}
4673
4674	<	final class EntrySet extends AbstractSet<Map.Entry<K,V>> {
4675	<	public Iterator<Map.Entry<K,V>> iterator() {
4676	<	return new EntryIterator();
4674	>	/**
4675	>	* A view of a ConcurrentHashMap as a {@link Collection} of
4676	>	* values, in which additions are disabled. This class cannot be
4677	>	* directly instantiated. See {@link #values()}.
4678	>	*/
4679	>	static final class ValuesView<K,V> extends CollectionView<K,V,V>
4680	>	implements Collection<V>, java.io.Serializable {
4681	>	private static final long serialVersionUID = 2249069246763182397L;
4682	>	ValuesView(ConcurrentHashMap<K,V> map) { super(map); }
4683	>	public final boolean contains(Object o) {
4684	>	return map.containsValue(o);
4685	>	}
4686	>
4687	>	public final boolean remove(Object o) {
4688	>	if (o != null) {
4689	>	for (Iterator<V> it = iterator(); it.hasNext();) {
4690	>	if (o.equals(it.next())) {
4691	>	it.remove();
4692	>	return true;
4693	>	}
4694	>	}
4695	>	}
4696	>	return false;
4697	>	}
4698	>
4699	>	public final Iterator<V> iterator() {
4700	>	ConcurrentHashMap<K,V> m = map;
4701	>	Node<K,V>[] t;
4702	>	int f = (t = m.table) == null ? 0 : t.length;
4703	>	return new ValueIterator<K,V>(t, f, 0, f, m);
4704	>	}
4705	>
4706	>	public final boolean add(V e) {
4707	>	throw new UnsupportedOperationException();
4708	>	}
4709	>	public final boolean addAll(Collection<? extends V> c) {
4710	>	throw new UnsupportedOperationException();
4711	>	}
4712	>
4713	>	public boolean removeIf(Predicate<? super V> filter) {
4714	>	return map.removeValueIf(filter);
4715	>	}
4716	>
4717	>	public Spliterator<V> spliterator() {
4718	>	Node<K,V>[] t;
4719	>	ConcurrentHashMap<K,V> m = map;
4720	>	long n = m.sumCount();
4721	>	int f = (t = m.table) == null ? 0 : t.length;
4722	>	return new ValueSpliterator<K,V>(t, f, 0, f, n < 0L ? 0L : n);
4723	>	}
4724	>
4725	>	public void forEach(Consumer<? super V> action) {
4726	>	if (action == null) throw new NullPointerException();
4727	>	Node<K,V>[] t;
4728	>	if ((t = map.table) != null) {
4729	>	Traverser<K,V> it = new Traverser<K,V>(t, t.length, 0, t.length);
4730	>	for (Node<K,V> p; (p = it.advance()) != null; )
4731	>	action.accept(p.val);
4732	>	}
4733		}
4734	+	}
4735	+
4736	+	/**
4737	+	* A view of a ConcurrentHashMap as a {@link Set} of (key, value)
4738	+	* entries.  This class cannot be directly instantiated. See
4739	+	* {@link #entrySet()}.
4740	+	*/
4741	+	static final class EntrySetView<K,V> extends CollectionView<K,V,Map.Entry<K,V>>
4742	+	implements Set<Map.Entry<K,V>>, java.io.Serializable {
4743	+	private static final long serialVersionUID = 2249069246763182397L;
4744	+	EntrySetView(ConcurrentHashMap<K,V> map) { super(map); }
4745	+
4746		public boolean contains(Object o) {
4747	<	if (!(o instanceof Map.Entry))
4748	<	return false;
4749	<	Map.Entry<?,?> e = (Map.Entry<?,?>)o;
4750	<	V v = ConcurrentHashMap.this.get(e.getKey());
4751	<	return v != null && v.equals(e.getValue());
4747	>	Object k, v, r; Map.Entry<?,?> e;
4748	>	return ((o instanceof Map.Entry) &&
4749	>	(k = (e = (Map.Entry<?,?>)o).getKey()) != null &&
4750	>	(r = map.get(k)) != null &&
4751	>	(v = e.getValue()) != null &&
4752	>	(v == r || v.equals(r)));
4753		}
4754	+
4755		public boolean remove(Object o) {
4756	<	if (!(o instanceof Map.Entry))
4757	<	return false;
4758	<	Map.Entry<?,?> e = (Map.Entry<?,?>)o;
4759	<	return ConcurrentHashMap.this.remove(e.getKey(), e.getValue());
4756	>	Object k, v; Map.Entry<?,?> e;
4757	>	return ((o instanceof Map.Entry) &&
4758	>	(k = (e = (Map.Entry<?,?>)o).getKey()) != null &&
4759	>	(v = e.getValue()) != null &&
4760	>	map.remove(k, v));
4761	>	}
4762	>
4763	>	/**
4764	>	* @return an iterator over the entries of the backing map
4765	>	*/
4766	>	public Iterator<Map.Entry<K,V>> iterator() {
4767	>	ConcurrentHashMap<K,V> m = map;
4768	>	Node<K,V>[] t;
4769	>	int f = (t = m.table) == null ? 0 : t.length;
4770	>	return new EntryIterator<K,V>(t, f, 0, f, m);
4771		}
4772	<	public int size() {
4773	<	return ConcurrentHashMap.this.size();
4772	>
4773	>	public boolean add(Entry<K,V> e) {
4774	>	return map.putVal(e.getKey(), e.getValue(), false) == null;
4775		}
4776	<	public void clear() {
4777	<	ConcurrentHashMap.this.clear();
4776	>
4777	>	public boolean addAll(Collection<? extends Entry<K,V>> c) {
4778	>	boolean added = false;
4779	>	for (Entry<K,V> e : c) {
4780	>	if (add(e))
4781	>	added = true;
4782	>	}
4783	>	return added;
4784		}
4785	+
4786	+	public boolean removeIf(Predicate<? super Entry<K,V>> filter) {
4787	+	return map.removeEntryIf(filter);
4788	+	}
4789	+
4790	+	public final int hashCode() {
4791	+	int h = 0;
4792	+	Node<K,V>[] t;
4793	+	if ((t = map.table) != null) {
4794	+	Traverser<K,V> it = new Traverser<K,V>(t, t.length, 0, t.length);
4795	+	for (Node<K,V> p; (p = it.advance()) != null; ) {
4796	+	h += p.hashCode();
4797	+	}
4798	+	}
4799	+	return h;
4800	+	}
4801	+
4802	+	public final boolean equals(Object o) {
4803	+	Set<?> c;
4804	+	return ((o instanceof Set) &&
4805	+	((c = (Set<?>)o) == this ||
4806	+	(containsAll(c) && c.containsAll(this))));
4807	+	}
4808	+
4809	+	public Spliterator<Map.Entry<K,V>> spliterator() {
4810	+	Node<K,V>[] t;
4811	+	ConcurrentHashMap<K,V> m = map;
4812	+	long n = m.sumCount();
4813	+	int f = (t = m.table) == null ? 0 : t.length;
4814	+	return new EntrySpliterator<K,V>(t, f, 0, f, n < 0L ? 0L : n, m);
4815	+	}
4816	+
4817	+	public void forEach(Consumer<? super Map.Entry<K,V>> action) {
4818	+	if (action == null) throw new NullPointerException();
4819	+	Node<K,V>[] t;
4820	+	if ((t = map.table) != null) {
4821	+	Traverser<K,V> it = new Traverser<K,V>(t, t.length, 0, t.length);
4822	+	for (Node<K,V> p; (p = it.advance()) != null; )
4823	+	action.accept(new MapEntry<K,V>(p.key, p.val, map));
4824	+	}
4825	+	}
4826	+
4827		}
4828
4829	<	/* ---------------- Serialization Support -------------- */
4829	>	// -------------------------------------------------------
4830
4831		/**
4832	<	* Save the state of the <tt>ConcurrentHashMap</tt> instance to a
4833	<	* stream (i.e., serialize it).
1226	<	* @param s the stream
1227	<	* @serialData
1228	<	* the key (Object) and value (Object)
1229	<	* for each key-value mapping, followed by a null pair.
1230	<	* The key-value mappings are emitted in no particular order.
4832	>	* Base class for bulk tasks. Repeats some fields and code from
4833	>	* class Traverser, because we need to subclass CountedCompleter.
4834		*/
4835	<	private void writeObject(java.io.ObjectOutputStream s) throws IOException  {
4836	<	s.defaultWriteObject();
4835	>	@SuppressWarnings("serial")
4836	>	abstract static class BulkTask<K,V,R> extends CountedCompleter<R> {
4837	>	Node<K,V>[] tab;        // same as Traverser
4838	>	Node<K,V> next;
4839	>	TableStack<K,V> stack, spare;
4840	>	int index;
4841	>	int baseIndex;
4842	>	int baseLimit;
4843	>	final int baseSize;
4844	>	int batch;              // split control
4845	>
4846	>	BulkTask(BulkTask<K,V,?> par, int b, int i, int f, Node<K,V>[] t) {
4847	>	super(par);
4848	>	this.batch = b;
4849	>	this.index = this.baseIndex = i;
4850	>	if ((this.tab = t) == null)
4851	>	this.baseSize = this.baseLimit = 0;
4852	>	else if (par == null)
4853	>	this.baseSize = this.baseLimit = t.length;
4854	>	else {
4855	>	this.baseLimit = f;
4856	>	this.baseSize = par.baseSize;
4857	>	}
4858	>	}
4859
4860	<	for (int k = 0; k < segments.length; ++k) {
4861	<	Segment<K,V> seg = segments[k];
4862	<	seg.lock();
4863	<	try {
4864	<	HashEntry<K,V>[] tab = seg.table;
4865	<	for (int i = 0; i < tab.length; ++i) {
4866	<	for (HashEntry<K,V> e = tab[i]; e != null; e = e.next) {
4867	<	s.writeObject(e.key);
4868	<	s.writeObject(e.value);
4860	>	/**
4861	>	* Same as Traverser version
4862	>	*/
4863	>	final Node<K,V> advance() {
4864	>	Node<K,V> e;
4865	>	if ((e = next) != null)
4866	>	e = e.next;
4867	>	for (;;) {
4868	>	Node<K,V>[] t; int i, n;
4869	>	if (e != null)
4870	>	return next = e;
4871	>	if (baseIndex >= baseLimit || (t = tab) == null ||
4872	>	(n = t.length) <= (i = index) || i < 0)
4873	>	return next = null;
4874	>	if ((e = tabAt(t, i)) != null && e.hash < 0) {
4875	>	if (e instanceof ForwardingNode) {
4876	>	tab = ((ForwardingNode<K,V>)e).nextTable;
4877	>	e = null;
4878	>	pushState(t, i, n);
4879	>	continue;
4880		}
4881	+	else if (e instanceof TreeBin)
4882	+	e = ((TreeBin<K,V>)e).first;
4883	+	else
4884	+	e = null;
4885		}
4886	<	} finally {
4887	<	seg.unlock();
4886	>	if (stack != null)
4887	>	recoverState(n);
4888	>	else if ((index = i + baseSize) >= n)
4889	>	index = ++baseIndex;
4890		}
4891		}
4892	<	s.writeObject(null);
4893	<	s.writeObject(null);
4892	>
4893	>	private void pushState(Node<K,V>[] t, int i, int n) {
4894	>	TableStack<K,V> s = spare;
4895	>	if (s != null)
4896	>	spare = s.next;
4897	>	else
4898	>	s = new TableStack<K,V>();
4899	>	s.tab = t;
4900	>	s.length = n;
4901	>	s.index = i;
4902	>	s.next = stack;
4903	>	stack = s;
4904	>	}
4905	>
4906	>	private void recoverState(int n) {
4907	>	TableStack<K,V> s; int len;
4908	>	while ((s = stack) != null && (index += (len = s.length)) >= n) {
4909	>	n = len;
4910	>	index = s.index;
4911	>	tab = s.tab;
4912	>	s.tab = null;
4913	>	TableStack<K,V> next = s.next;
4914	>	s.next = spare; // save for reuse
4915	>	stack = next;
4916	>	spare = s;
4917	>	}
4918	>	if (s == null && (index += baseSize) >= n)
4919	>	index = ++baseIndex;
4920	>	}
4921		}
4922
4923	<	/**
4924	<	* Reconstitute the <tt>ConcurrentHashMap</tt> instance from a
4925	<	* stream (i.e., deserialize it).
4926	<	* @param s the stream
4927	<	*/
4928	<	private void readObject(java.io.ObjectInputStream s)
4929	<	throws IOException, ClassNotFoundException  {
4930	<	s.defaultReadObject();
4923	>	/*
4924	>	* Task classes. Coded in a regular but ugly format/style to
4925	>	* simplify checks that each variant differs in the right way from
4926	>	* others. The null screenings exist because compilers cannot tell
4927	>	* that we've already null-checked task arguments, so we force
4928	>	* simplest hoisted bypass to help avoid convoluted traps.
4929	>	*/
4930	>	@SuppressWarnings("serial")
4931	>	static final class ForEachKeyTask<K,V>
4932	>	extends BulkTask<K,V,Void> {
4933	>	final Consumer<? super K> action;
4934	>	ForEachKeyTask
4935	>	(BulkTask<K,V,?> p, int b, int i, int f, Node<K,V>[] t,
4936	>	Consumer<? super K> action) {
4937	>	super(p, b, i, f, t);
4938	>	this.action = action;
4939	>	}
4940	>	public final void compute() {
4941	>	final Consumer<? super K> action;
4942	>	if ((action = this.action) != null) {
4943	>	for (int i = baseIndex, f, h; batch > 0 &&
4944	>	(h = ((f = baseLimit) + i) >>> 1) > i;) {
4945	>	addToPendingCount(1);
4946	>	new ForEachKeyTask<K,V>
4947	>	(this, batch >>>= 1, baseLimit = h, f, tab,
4948	>	action).fork();
4949	>	}
4950	>	for (Node<K,V> p; (p = advance()) != null;)
4951	>	action.accept(p.key);
4952	>	propagateCompletion();
4953	>	}
4954	>	}
4955	>	}
4956
4957	<	// Initialize each segment to be minimally sized, and let grow.
4958	<	for (int i = 0; i < segments.length; ++i) {
4959	<	segments[i].setTable(new HashEntry[1]);
4957	>	@SuppressWarnings("serial")
4958	>	static final class ForEachValueTask<K,V>
4959	>	extends BulkTask<K,V,Void> {
4960	>	final Consumer<? super V> action;
4961	>	ForEachValueTask
4962	>	(BulkTask<K,V,?> p, int b, int i, int f, Node<K,V>[] t,
4963	>	Consumer<? super V> action) {
4964	>	super(p, b, i, f, t);
4965	>	this.action = action;
4966	>	}
4967	>	public final void compute() {
4968	>	final Consumer<? super V> action;
4969	>	if ((action = this.action) != null) {
4970	>	for (int i = baseIndex, f, h; batch > 0 &&
4971	>	(h = ((f = baseLimit) + i) >>> 1) > i;) {
4972	>	addToPendingCount(1);
4973	>	new ForEachValueTask<K,V>
4974	>	(this, batch >>>= 1, baseLimit = h, f, tab,
4975	>	action).fork();
4976	>	}
4977	>	for (Node<K,V> p; (p = advance()) != null;)
4978	>	action.accept(p.val);
4979	>	propagateCompletion();
4980	>	}
4981		}
4982	+	}
4983
4984	<	// Read the keys and values, and put the mappings in the table
4985	<	for (;;) {
4986	<	K key = (K) s.readObject();
4987	<	V value = (V) s.readObject();
4988	<	if (key == null)
4989	<	break;
4990	<	put(key, value);
4984	>	@SuppressWarnings("serial")
4985	>	static final class ForEachEntryTask<K,V>
4986	>	extends BulkTask<K,V,Void> {
4987	>	final Consumer<? super Entry<K,V>> action;
4988	>	ForEachEntryTask
4989	>	(BulkTask<K,V,?> p, int b, int i, int f, Node<K,V>[] t,
4990	>	Consumer<? super Entry<K,V>> action) {
4991	>	super(p, b, i, f, t);
4992	>	this.action = action;
4993	>	}
4994	>	public final void compute() {
4995	>	final Consumer<? super Entry<K,V>> action;
4996	>	if ((action = this.action) != null) {
4997	>	for (int i = baseIndex, f, h; batch > 0 &&
4998	>	(h = ((f = baseLimit) + i) >>> 1) > i;) {
4999	>	addToPendingCount(1);
5000	>	new ForEachEntryTask<K,V>
5001	>	(this, batch >>>= 1, baseLimit = h, f, tab,
5002	>	action).fork();
5003	>	}
5004	>	for (Node<K,V> p; (p = advance()) != null; )
5005	>	action.accept(p);
5006	>	propagateCompletion();
5007	>	}
5008	>	}
5009	>	}
5010	>
5011	>	@SuppressWarnings("serial")
5012	>	static final class ForEachMappingTask<K,V>
5013	>	extends BulkTask<K,V,Void> {
5014	>	final BiConsumer<? super K, ? super V> action;
5015	>	ForEachMappingTask
5016	>	(BulkTask<K,V,?> p, int b, int i, int f, Node<K,V>[] t,
5017	>	BiConsumer<? super K,? super V> action) {
5018	>	super(p, b, i, f, t);
5019	>	this.action = action;
5020	>	}
5021	>	public final void compute() {
5022	>	final BiConsumer<? super K, ? super V> action;
5023	>	if ((action = this.action) != null) {
5024	>	for (int i = baseIndex, f, h; batch > 0 &&
5025	>	(h = ((f = baseLimit) + i) >>> 1) > i;) {
5026	>	addToPendingCount(1);
5027	>	new ForEachMappingTask<K,V>
5028	>	(this, batch >>>= 1, baseLimit = h, f, tab,
5029	>	action).fork();
5030	>	}
5031	>	for (Node<K,V> p; (p = advance()) != null; )
5032	>	action.accept(p.key, p.val);
5033	>	propagateCompletion();
5034	>	}
5035	>	}
5036	>	}
5037	>
5038	>	@SuppressWarnings("serial")
5039	>	static final class ForEachTransformedKeyTask<K,V,U>
5040	>	extends BulkTask<K,V,Void> {
5041	>	final Function<? super K, ? extends U> transformer;
5042	>	final Consumer<? super U> action;
5043	>	ForEachTransformedKeyTask
5044	>	(BulkTask<K,V,?> p, int b, int i, int f, Node<K,V>[] t,
5045	>	Function<? super K, ? extends U> transformer, Consumer<? super U> action) {
5046	>	super(p, b, i, f, t);
5047	>	this.transformer = transformer; this.action = action;
5048	>	}
5049	>	public final void compute() {
5050	>	final Function<? super K, ? extends U> transformer;
5051	>	final Consumer<? super U> action;
5052	>	if ((transformer = this.transformer) != null &&
5053	>	(action = this.action) != null) {
5054	>	for (int i = baseIndex, f, h; batch > 0 &&
5055	>	(h = ((f = baseLimit) + i) >>> 1) > i;) {
5056	>	addToPendingCount(1);
5057	>	new ForEachTransformedKeyTask<K,V,U>
5058	>	(this, batch >>>= 1, baseLimit = h, f, tab,
5059	>	transformer, action).fork();
5060	>	}
5061	>	for (Node<K,V> p; (p = advance()) != null; ) {
5062	>	U u;
5063	>	if ((u = transformer.apply(p.key)) != null)
5064	>	action.accept(u);
5065	>	}
5066	>	propagateCompletion();
5067	>	}
5068		}
5069		}
5070	+
5071	+	@SuppressWarnings("serial")
5072	+	static final class ForEachTransformedValueTask<K,V,U>
5073	+	extends BulkTask<K,V,Void> {
5074	+	final Function<? super V, ? extends U> transformer;
5075	+	final Consumer<? super U> action;
5076	+	ForEachTransformedValueTask
5077	+	(BulkTask<K,V,?> p, int b, int i, int f, Node<K,V>[] t,
5078	+	Function<? super V, ? extends U> transformer, Consumer<? super U> action) {
5079	+	super(p, b, i, f, t);
5080	+	this.transformer = transformer; this.action = action;
5081	+	}
5082	+	public final void compute() {
5083	+	final Function<? super V, ? extends U> transformer;
5084	+	final Consumer<? super U> action;
5085	+	if ((transformer = this.transformer) != null &&
5086	+	(action = this.action) != null) {
5087	+	for (int i = baseIndex, f, h; batch > 0 &&
5088	+	(h = ((f = baseLimit) + i) >>> 1) > i;) {
5089	+	addToPendingCount(1);
5090	+	new ForEachTransformedValueTask<K,V,U>
5091	+	(this, batch >>>= 1, baseLimit = h, f, tab,
5092	+	transformer, action).fork();
5093	+	}
5094	+	for (Node<K,V> p; (p = advance()) != null; ) {
5095	+	U u;
5096	+	if ((u = transformer.apply(p.val)) != null)
5097	+	action.accept(u);
5098	+	}
5099	+	propagateCompletion();
5100	+	}
5101	+	}
5102	+	}
5103	+
5104	+	@SuppressWarnings("serial")
5105	+	static final class ForEachTransformedEntryTask<K,V,U>
5106	+	extends BulkTask<K,V,Void> {
5107	+	final Function<Map.Entry<K,V>, ? extends U> transformer;
5108	+	final Consumer<? super U> action;
5109	+	ForEachTransformedEntryTask
5110	+	(BulkTask<K,V,?> p, int b, int i, int f, Node<K,V>[] t,
5111	+	Function<Map.Entry<K,V>, ? extends U> transformer, Consumer<? super U> action) {
5112	+	super(p, b, i, f, t);
5113	+	this.transformer = transformer; this.action = action;
5114	+	}
5115	+	public final void compute() {
5116	+	final Function<Map.Entry<K,V>, ? extends U> transformer;
5117	+	final Consumer<? super U> action;
5118	+	if ((transformer = this.transformer) != null &&
5119	+	(action = this.action) != null) {
5120	+	for (int i = baseIndex, f, h; batch > 0 &&
5121	+	(h = ((f = baseLimit) + i) >>> 1) > i;) {
5122	+	addToPendingCount(1);
5123	+	new ForEachTransformedEntryTask<K,V,U>
5124	+	(this, batch >>>= 1, baseLimit = h, f, tab,
5125	+	transformer, action).fork();
5126	+	}
5127	+	for (Node<K,V> p; (p = advance()) != null; ) {
5128	+	U u;
5129	+	if ((u = transformer.apply(p)) != null)
5130	+	action.accept(u);
5131	+	}
5132	+	propagateCompletion();
5133	+	}
5134	+	}
5135	+	}
5136	+
5137	+	@SuppressWarnings("serial")
5138	+	static final class ForEachTransformedMappingTask<K,V,U>
5139	+	extends BulkTask<K,V,Void> {
5140	+	final BiFunction<? super K, ? super V, ? extends U> transformer;
5141	+	final Consumer<? super U> action;
5142	+	ForEachTransformedMappingTask
5143	+	(BulkTask<K,V,?> p, int b, int i, int f, Node<K,V>[] t,
5144	+	BiFunction<? super K, ? super V, ? extends U> transformer,
5145	+	Consumer<? super U> action) {
5146	+	super(p, b, i, f, t);
5147	+	this.transformer = transformer; this.action = action;
5148	+	}
5149	+	public final void compute() {
5150	+	final BiFunction<? super K, ? super V, ? extends U> transformer;
5151	+	final Consumer<? super U> action;
5152	+	if ((transformer = this.transformer) != null &&
5153	+	(action = this.action) != null) {
5154	+	for (int i = baseIndex, f, h; batch > 0 &&
5155	+	(h = ((f = baseLimit) + i) >>> 1) > i;) {
5156	+	addToPendingCount(1);
5157	+	new ForEachTransformedMappingTask<K,V,U>
5158	+	(this, batch >>>= 1, baseLimit = h, f, tab,
5159	+	transformer, action).fork();
5160	+	}
5161	+	for (Node<K,V> p; (p = advance()) != null; ) {
5162	+	U u;
5163	+	if ((u = transformer.apply(p.key, p.val)) != null)
5164	+	action.accept(u);
5165	+	}
5166	+	propagateCompletion();
5167	+	}
5168	+	}
5169	+	}
5170	+
5171	+	@SuppressWarnings("serial")
5172	+	static final class SearchKeysTask<K,V,U>
5173	+	extends BulkTask<K,V,U> {
5174	+	final Function<? super K, ? extends U> searchFunction;
5175	+	final AtomicReference<U> result;
5176	+	SearchKeysTask
5177	+	(BulkTask<K,V,?> p, int b, int i, int f, Node<K,V>[] t,
5178	+	Function<? super K, ? extends U> searchFunction,
5179	+	AtomicReference<U> result) {
5180	+	super(p, b, i, f, t);
5181	+	this.searchFunction = searchFunction; this.result = result;
5182	+	}
5183	+	public final U getRawResult() { return result.get(); }
5184	+	public final void compute() {
5185	+	final Function<? super K, ? extends U> searchFunction;
5186	+	final AtomicReference<U> result;
5187	+	if ((searchFunction = this.searchFunction) != null &&
5188	+	(result = this.result) != null) {
5189	+	for (int i = baseIndex, f, h; batch > 0 &&
5190	+	(h = ((f = baseLimit) + i) >>> 1) > i;) {
5191	+	if (result.get() != null)
5192	+	return;
5193	+	addToPendingCount(1);
5194	+	new SearchKeysTask<K,V,U>
5195	+	(this, batch >>>= 1, baseLimit = h, f, tab,
5196	+	searchFunction, result).fork();
5197	+	}
5198	+	while (result.get() == null) {
5199	+	U u;
5200	+	Node<K,V> p;
5201	+	if ((p = advance()) == null) {
5202	+	propagateCompletion();
5203	+	break;
5204	+	}
5205	+	if ((u = searchFunction.apply(p.key)) != null) {
5206	+	if (result.compareAndSet(null, u))
5207	+	quietlyCompleteRoot();
5208	+	break;
5209	+	}
5210	+	}
5211	+	}
5212	+	}
5213	+	}
5214	+
5215	+	@SuppressWarnings("serial")
5216	+	static final class SearchValuesTask<K,V,U>
5217	+	extends BulkTask<K,V,U> {
5218	+	final Function<? super V, ? extends U> searchFunction;
5219	+	final AtomicReference<U> result;
5220	+	SearchValuesTask
5221	+	(BulkTask<K,V,?> p, int b, int i, int f, Node<K,V>[] t,
5222	+	Function<? super V, ? extends U> searchFunction,
5223	+	AtomicReference<U> result) {
5224	+	super(p, b, i, f, t);
5225	+	this.searchFunction = searchFunction; this.result = result;
5226	+	}
5227	+	public final U getRawResult() { return result.get(); }
5228	+	public final void compute() {
5229	+	final Function<? super V, ? extends U> searchFunction;
5230	+	final AtomicReference<U> result;
5231	+	if ((searchFunction = this.searchFunction) != null &&
5232	+	(result = this.result) != null) {
5233	+	for (int i = baseIndex, f, h; batch > 0 &&
5234	+	(h = ((f = baseLimit) + i) >>> 1) > i;) {
5235	+	if (result.get() != null)
5236	+	return;
5237	+	addToPendingCount(1);
5238	+	new SearchValuesTask<K,V,U>
5239	+	(this, batch >>>= 1, baseLimit = h, f, tab,
5240	+	searchFunction, result).fork();
5241	+	}
5242	+	while (result.get() == null) {
5243	+	U u;
5244	+	Node<K,V> p;
5245	+	if ((p = advance()) == null) {
5246	+	propagateCompletion();
5247	+	break;
5248	+	}
5249	+	if ((u = searchFunction.apply(p.val)) != null) {
5250	+	if (result.compareAndSet(null, u))
5251	+	quietlyCompleteRoot();
5252	+	break;
5253	+	}
5254	+	}
5255	+	}
5256	+	}
5257	+	}
5258	+
5259	+	@SuppressWarnings("serial")
5260	+	static final class SearchEntriesTask<K,V,U>
5261	+	extends BulkTask<K,V,U> {
5262	+	final Function<Entry<K,V>, ? extends U> searchFunction;
5263	+	final AtomicReference<U> result;
5264	+	SearchEntriesTask
5265	+	(BulkTask<K,V,?> p, int b, int i, int f, Node<K,V>[] t,
5266	+	Function<Entry<K,V>, ? extends U> searchFunction,
5267	+	AtomicReference<U> result) {
5268	+	super(p, b, i, f, t);
5269	+	this.searchFunction = searchFunction; this.result = result;
5270	+	}
5271	+	public final U getRawResult() { return result.get(); }
5272	+	public final void compute() {
5273	+	final Function<Entry<K,V>, ? extends U> searchFunction;
5274	+	final AtomicReference<U> result;
5275	+	if ((searchFunction = this.searchFunction) != null &&
5276	+	(result = this.result) != null) {
5277	+	for (int i = baseIndex, f, h; batch > 0 &&
5278	+	(h = ((f = baseLimit) + i) >>> 1) > i;) {
5279	+	if (result.get() != null)
5280	+	return;
5281	+	addToPendingCount(1);
5282	+	new SearchEntriesTask<K,V,U>
5283	+	(this, batch >>>= 1, baseLimit = h, f, tab,
5284	+	searchFunction, result).fork();
5285	+	}
5286	+	while (result.get() == null) {
5287	+	U u;
5288	+	Node<K,V> p;
5289	+	if ((p = advance()) == null) {
5290	+	propagateCompletion();
5291	+	break;
5292	+	}
5293	+	if ((u = searchFunction.apply(p)) != null) {
5294	+	if (result.compareAndSet(null, u))
5295	+	quietlyCompleteRoot();
5296	+	return;
5297	+	}
5298	+	}
5299	+	}
5300	+	}
5301	+	}
5302	+
5303	+	@SuppressWarnings("serial")
5304	+	static final class SearchMappingsTask<K,V,U>
5305	+	extends BulkTask<K,V,U> {
5306	+	final BiFunction<? super K, ? super V, ? extends U> searchFunction;
5307	+	final AtomicReference<U> result;
5308	+	SearchMappingsTask
5309	+	(BulkTask<K,V,?> p, int b, int i, int f, Node<K,V>[] t,
5310	+	BiFunction<? super K, ? super V, ? extends U> searchFunction,
5311	+	AtomicReference<U> result) {
5312	+	super(p, b, i, f, t);
5313	+	this.searchFunction = searchFunction; this.result = result;
5314	+	}
5315	+	public final U getRawResult() { return result.get(); }
5316	+	public final void compute() {
5317	+	final BiFunction<? super K, ? super V, ? extends U> searchFunction;
5318	+	final AtomicReference<U> result;
5319	+	if ((searchFunction = this.searchFunction) != null &&
5320	+	(result = this.result) != null) {
5321	+	for (int i = baseIndex, f, h; batch > 0 &&
5322	+	(h = ((f = baseLimit) + i) >>> 1) > i;) {
5323	+	if (result.get() != null)
5324	+	return;
5325	+	addToPendingCount(1);
5326	+	new SearchMappingsTask<K,V,U>
5327	+	(this, batch >>>= 1, baseLimit = h, f, tab,
5328	+	searchFunction, result).fork();
5329	+	}
5330	+	while (result.get() == null) {
5331	+	U u;
5332	+	Node<K,V> p;
5333	+	if ((p = advance()) == null) {
5334	+	propagateCompletion();
5335	+	break;
5336	+	}
5337	+	if ((u = searchFunction.apply(p.key, p.val)) != null) {
5338	+	if (result.compareAndSet(null, u))
5339	+	quietlyCompleteRoot();
5340	+	break;
5341	+	}
5342	+	}
5343	+	}
5344	+	}
5345	+	}
5346	+
5347	+	@SuppressWarnings("serial")
5348	+	static final class ReduceKeysTask<K,V>
5349	+	extends BulkTask<K,V,K> {
5350	+	final BiFunction<? super K, ? super K, ? extends K> reducer;
5351	+	K result;
5352	+	ReduceKeysTask<K,V> rights, nextRight;
5353	+	ReduceKeysTask
5354	+	(BulkTask<K,V,?> p, int b, int i, int f, Node<K,V>[] t,
5355	+	ReduceKeysTask<K,V> nextRight,
5356	+	BiFunction<? super K, ? super K, ? extends K> reducer) {
5357	+	super(p, b, i, f, t); this.nextRight = nextRight;
5358	+	this.reducer = reducer;
5359	+	}
5360	+	public final K getRawResult() { return result; }
5361	+	public final void compute() {
5362	+	final BiFunction<? super K, ? super K, ? extends K> reducer;
5363	+	if ((reducer = this.reducer) != null) {
5364	+	for (int i = baseIndex, f, h; batch > 0 &&
5365	+	(h = ((f = baseLimit) + i) >>> 1) > i;) {
5366	+	addToPendingCount(1);
5367	+	(rights = new ReduceKeysTask<K,V>
5368	+	(this, batch >>>= 1, baseLimit = h, f, tab,
5369	+	rights, reducer)).fork();
5370	+	}
5371	+	K r = null;
5372	+	for (Node<K,V> p; (p = advance()) != null; ) {
5373	+	K u = p.key;
5374	+	r = (r == null) ? u : u == null ? r : reducer.apply(r, u);
5375	+	}
5376	+	result = r;
5377	+	CountedCompleter<?> c;
5378	+	for (c = firstComplete(); c != null; c = c.nextComplete()) {
5379	+	@SuppressWarnings("unchecked")
5380	+	ReduceKeysTask<K,V>
5381	+	t = (ReduceKeysTask<K,V>)c,
5382	+	s = t.rights;
5383	+	while (s != null) {
5384	+	K tr, sr;
5385	+	if ((sr = s.result) != null)
5386	+	t.result = (((tr = t.result) == null) ? sr :
5387	+	reducer.apply(tr, sr));
5388	+	s = t.rights = s.nextRight;
5389	+	}
5390	+	}
5391	+	}
5392	+	}
5393	+	}
5394	+
5395	+	@SuppressWarnings("serial")
5396	+	static final class ReduceValuesTask<K,V>
5397	+	extends BulkTask<K,V,V> {
5398	+	final BiFunction<? super V, ? super V, ? extends V> reducer;
5399	+	V result;
5400	+	ReduceValuesTask<K,V> rights, nextRight;
5401	+	ReduceValuesTask
5402	+	(BulkTask<K,V,?> p, int b, int i, int f, Node<K,V>[] t,
5403	+	ReduceValuesTask<K,V> nextRight,
5404	+	BiFunction<? super V, ? super V, ? extends V> reducer) {
5405	+	super(p, b, i, f, t); this.nextRight = nextRight;
5406	+	this.reducer = reducer;
5407	+	}
5408	+	public final V getRawResult() { return result; }
5409	+	public final void compute() {
5410	+	final BiFunction<? super V, ? super V, ? extends V> reducer;
5411	+	if ((reducer = this.reducer) != null) {
5412	+	for (int i = baseIndex, f, h; batch > 0 &&
5413	+	(h = ((f = baseLimit) + i) >>> 1) > i;) {
5414	+	addToPendingCount(1);
5415	+	(rights = new ReduceValuesTask<K,V>
5416	+	(this, batch >>>= 1, baseLimit = h, f, tab,
5417	+	rights, reducer)).fork();
5418	+	}
5419	+	V r = null;
5420	+	for (Node<K,V> p; (p = advance()) != null; ) {
5421	+	V v = p.val;
5422	+	r = (r == null) ? v : reducer.apply(r, v);
5423	+	}
5424	+	result = r;
5425	+	CountedCompleter<?> c;
5426	+	for (c = firstComplete(); c != null; c = c.nextComplete()) {
5427	+	@SuppressWarnings("unchecked")
5428	+	ReduceValuesTask<K,V>
5429	+	t = (ReduceValuesTask<K,V>)c,
5430	+	s = t.rights;
5431	+	while (s != null) {
5432	+	V tr, sr;
5433	+	if ((sr = s.result) != null)
5434	+	t.result = (((tr = t.result) == null) ? sr :
5435	+	reducer.apply(tr, sr));
5436	+	s = t.rights = s.nextRight;
5437	+	}
5438	+	}
5439	+	}
5440	+	}
5441	+	}
5442	+
5443	+	@SuppressWarnings("serial")
5444	+	static final class ReduceEntriesTask<K,V>
5445	+	extends BulkTask<K,V,Map.Entry<K,V>> {
5446	+	final BiFunction<Map.Entry<K,V>, Map.Entry<K,V>, ? extends Map.Entry<K,V>> reducer;
5447	+	Map.Entry<K,V> result;
5448	+	ReduceEntriesTask<K,V> rights, nextRight;
5449	+	ReduceEntriesTask
5450	+	(BulkTask<K,V,?> p, int b, int i, int f, Node<K,V>[] t,
5451	+	ReduceEntriesTask<K,V> nextRight,
5452	+	BiFunction<Entry<K,V>, Map.Entry<K,V>, ? extends Map.Entry<K,V>> reducer) {
5453	+	super(p, b, i, f, t); this.nextRight = nextRight;
5454	+	this.reducer = reducer;
5455	+	}
5456	+	public final Map.Entry<K,V> getRawResult() { return result; }
5457	+	public final void compute() {
5458	+	final BiFunction<Map.Entry<K,V>, Map.Entry<K,V>, ? extends Map.Entry<K,V>> reducer;
5459	+	if ((reducer = this.reducer) != null) {
5460	+	for (int i = baseIndex, f, h; batch > 0 &&
5461	+	(h = ((f = baseLimit) + i) >>> 1) > i;) {
5462	+	addToPendingCount(1);
5463	+	(rights = new ReduceEntriesTask<K,V>
5464	+	(this, batch >>>= 1, baseLimit = h, f, tab,
5465	+	rights, reducer)).fork();
5466	+	}
5467	+	Map.Entry<K,V> r = null;
5468	+	for (Node<K,V> p; (p = advance()) != null; )
5469	+	r = (r == null) ? p : reducer.apply(r, p);
5470	+	result = r;
5471	+	CountedCompleter<?> c;
5472	+	for (c = firstComplete(); c != null; c = c.nextComplete()) {
5473	+	@SuppressWarnings("unchecked")
5474	+	ReduceEntriesTask<K,V>
5475	+	t = (ReduceEntriesTask<K,V>)c,
5476	+	s = t.rights;
5477	+	while (s != null) {
5478	+	Map.Entry<K,V> tr, sr;
5479	+	if ((sr = s.result) != null)
5480	+	t.result = (((tr = t.result) == null) ? sr :
5481	+	reducer.apply(tr, sr));
5482	+	s = t.rights = s.nextRight;
5483	+	}
5484	+	}
5485	+	}
5486	+	}
5487	+	}
5488	+
5489	+	@SuppressWarnings("serial")
5490	+	static final class MapReduceKeysTask<K,V,U>
5491	+	extends BulkTask<K,V,U> {
5492	+	final Function<? super K, ? extends U> transformer;
5493	+	final BiFunction<? super U, ? super U, ? extends U> reducer;
5494	+	U result;
5495	+	MapReduceKeysTask<K,V,U> rights, nextRight;
5496	+	MapReduceKeysTask
5497	+	(BulkTask<K,V,?> p, int b, int i, int f, Node<K,V>[] t,
5498	+	MapReduceKeysTask<K,V,U> nextRight,
5499	+	Function<? super K, ? extends U> transformer,
5500	+	BiFunction<? super U, ? super U, ? extends U> reducer) {
5501	+	super(p, b, i, f, t); this.nextRight = nextRight;
5502	+	this.transformer = transformer;
5503	+	this.reducer = reducer;
5504	+	}
5505	+	public final U getRawResult() { return result; }
5506	+	public final void compute() {
5507	+	final Function<? super K, ? extends U> transformer;
5508	+	final BiFunction<? super U, ? super U, ? extends U> reducer;
5509	+	if ((transformer = this.transformer) != null &&
5510	+	(reducer = this.reducer) != null) {
5511	+	for (int i = baseIndex, f, h; batch > 0 &&
5512	+	(h = ((f = baseLimit) + i) >>> 1) > i;) {
5513	+	addToPendingCount(1);
5514	+	(rights = new MapReduceKeysTask<K,V,U>
5515	+	(this, batch >>>= 1, baseLimit = h, f, tab,
5516	+	rights, transformer, reducer)).fork();
5517	+	}
5518	+	U r = null;
5519	+	for (Node<K,V> p; (p = advance()) != null; ) {
5520	+	U u;
5521	+	if ((u = transformer.apply(p.key)) != null)
5522	+	r = (r == null) ? u : reducer.apply(r, u);
5523	+	}
5524	+	result = r;
5525	+	CountedCompleter<?> c;
5526	+	for (c = firstComplete(); c != null; c = c.nextComplete()) {
5527	+	@SuppressWarnings("unchecked")
5528	+	MapReduceKeysTask<K,V,U>
5529	+	t = (MapReduceKeysTask<K,V,U>)c,
5530	+	s = t.rights;
5531	+	while (s != null) {
5532	+	U tr, sr;
5533	+	if ((sr = s.result) != null)
5534	+	t.result = (((tr = t.result) == null) ? sr :
5535	+	reducer.apply(tr, sr));
5536	+	s = t.rights = s.nextRight;
5537	+	}
5538	+	}
5539	+	}
5540	+	}
5541	+	}
5542	+
5543	+	@SuppressWarnings("serial")
5544	+	static final class MapReduceValuesTask<K,V,U>
5545	+	extends BulkTask<K,V,U> {
5546	+	final Function<? super V, ? extends U> transformer;
5547	+	final BiFunction<? super U, ? super U, ? extends U> reducer;
5548	+	U result;
5549	+	MapReduceValuesTask<K,V,U> rights, nextRight;
5550	+	MapReduceValuesTask
5551	+	(BulkTask<K,V,?> p, int b, int i, int f, Node<K,V>[] t,
5552	+	MapReduceValuesTask<K,V,U> nextRight,
5553	+	Function<? super V, ? extends U> transformer,
5554	+	BiFunction<? super U, ? super U, ? extends U> reducer) {
5555	+	super(p, b, i, f, t); this.nextRight = nextRight;
5556	+	this.transformer = transformer;
5557	+	this.reducer = reducer;
5558	+	}
5559	+	public final U getRawResult() { return result; }
5560	+	public final void compute() {
5561	+	final Function<? super V, ? extends U> transformer;
5562	+	final BiFunction<? super U, ? super U, ? extends U> reducer;
5563	+	if ((transformer = this.transformer) != null &&
5564	+	(reducer = this.reducer) != null) {
5565	+	for (int i = baseIndex, f, h; batch > 0 &&
5566	+	(h = ((f = baseLimit) + i) >>> 1) > i;) {
5567	+	addToPendingCount(1);
5568	+	(rights = new MapReduceValuesTask<K,V,U>
5569	+	(this, batch >>>= 1, baseLimit = h, f, tab,
5570	+	rights, transformer, reducer)).fork();
5571	+	}
5572	+	U r = null;
5573	+	for (Node<K,V> p; (p = advance()) != null; ) {
5574	+	U u;
5575	+	if ((u = transformer.apply(p.val)) != null)
5576	+	r = (r == null) ? u : reducer.apply(r, u);
5577	+	}
5578	+	result = r;
5579	+	CountedCompleter<?> c;
5580	+	for (c = firstComplete(); c != null; c = c.nextComplete()) {
5581	+	@SuppressWarnings("unchecked")
5582	+	MapReduceValuesTask<K,V,U>
5583	+	t = (MapReduceValuesTask<K,V,U>)c,
5584	+	s = t.rights;
5585	+	while (s != null) {
5586	+	U tr, sr;
5587	+	if ((sr = s.result) != null)
5588	+	t.result = (((tr = t.result) == null) ? sr :
5589	+	reducer.apply(tr, sr));
5590	+	s = t.rights = s.nextRight;
5591	+	}
5592	+	}
5593	+	}
5594	+	}
5595	+	}
5596	+
5597	+	@SuppressWarnings("serial")
5598	+	static final class MapReduceEntriesTask<K,V,U>
5599	+	extends BulkTask<K,V,U> {
5600	+	final Function<Map.Entry<K,V>, ? extends U> transformer;
5601	+	final BiFunction<? super U, ? super U, ? extends U> reducer;
5602	+	U result;
5603	+	MapReduceEntriesTask<K,V,U> rights, nextRight;
5604	+	MapReduceEntriesTask
5605	+	(BulkTask<K,V,?> p, int b, int i, int f, Node<K,V>[] t,
5606	+	MapReduceEntriesTask<K,V,U> nextRight,
5607	+	Function<Map.Entry<K,V>, ? extends U> transformer,
5608	+	BiFunction<? super U, ? super U, ? extends U> reducer) {
5609	+	super(p, b, i, f, t); this.nextRight = nextRight;
5610	+	this.transformer = transformer;
5611	+	this.reducer = reducer;
5612	+	}
5613	+	public final U getRawResult() { return result; }
5614	+	public final void compute() {
5615	+	final Function<Map.Entry<K,V>, ? extends U> transformer;
5616	+	final BiFunction<? super U, ? super U, ? extends U> reducer;
5617	+	if ((transformer = this.transformer) != null &&
5618	+	(reducer = this.reducer) != null) {
5619	+	for (int i = baseIndex, f, h; batch > 0 &&
5620	+	(h = ((f = baseLimit) + i) >>> 1) > i;) {
5621	+	addToPendingCount(1);
5622	+	(rights = new MapReduceEntriesTask<K,V,U>
5623	+	(this, batch >>>= 1, baseLimit = h, f, tab,
5624	+	rights, transformer, reducer)).fork();
5625	+	}
5626	+	U r = null;
5627	+	for (Node<K,V> p; (p = advance()) != null; ) {
5628	+	U u;
5629	+	if ((u = transformer.apply(p)) != null)
5630	+	r = (r == null) ? u : reducer.apply(r, u);
5631	+	}
5632	+	result = r;
5633	+	CountedCompleter<?> c;
5634	+	for (c = firstComplete(); c != null; c = c.nextComplete()) {
5635	+	@SuppressWarnings("unchecked")
5636	+	MapReduceEntriesTask<K,V,U>
5637	+	t = (MapReduceEntriesTask<K,V,U>)c,
5638	+	s = t.rights;
5639	+	while (s != null) {
5640	+	U tr, sr;
5641	+	if ((sr = s.result) != null)
5642	+	t.result = (((tr = t.result) == null) ? sr :
5643	+	reducer.apply(tr, sr));
5644	+	s = t.rights = s.nextRight;
5645	+	}
5646	+	}
5647	+	}
5648	+	}
5649	+	}
5650	+
5651	+	@SuppressWarnings("serial")
5652	+	static final class MapReduceMappingsTask<K,V,U>
5653	+	extends BulkTask<K,V,U> {
5654	+	final BiFunction<? super K, ? super V, ? extends U> transformer;
5655	+	final BiFunction<? super U, ? super U, ? extends U> reducer;
5656	+	U result;
5657	+	MapReduceMappingsTask<K,V,U> rights, nextRight;
5658	+	MapReduceMappingsTask
5659	+	(BulkTask<K,V,?> p, int b, int i, int f, Node<K,V>[] t,
5660	+	MapReduceMappingsTask<K,V,U> nextRight,
5661	+	BiFunction<? super K, ? super V, ? extends U> transformer,
5662	+	BiFunction<? super U, ? super U, ? extends U> reducer) {
5663	+	super(p, b, i, f, t); this.nextRight = nextRight;
5664	+	this.transformer = transformer;
5665	+	this.reducer = reducer;
5666	+	}
5667	+	public final U getRawResult() { return result; }
5668	+	public final void compute() {
5669	+	final BiFunction<? super K, ? super V, ? extends U> transformer;
5670	+	final BiFunction<? super U, ? super U, ? extends U> reducer;
5671	+	if ((transformer = this.transformer) != null &&
5672	+	(reducer = this.reducer) != null) {
5673	+	for (int i = baseIndex, f, h; batch > 0 &&
5674	+	(h = ((f = baseLimit) + i) >>> 1) > i;) {
5675	+	addToPendingCount(1);
5676	+	(rights = new MapReduceMappingsTask<K,V,U>
5677	+	(this, batch >>>= 1, baseLimit = h, f, tab,
5678	+	rights, transformer, reducer)).fork();
5679	+	}
5680	+	U r = null;
5681	+	for (Node<K,V> p; (p = advance()) != null; ) {
5682	+	U u;
5683	+	if ((u = transformer.apply(p.key, p.val)) != null)
5684	+	r = (r == null) ? u : reducer.apply(r, u);
5685	+	}
5686	+	result = r;
5687	+	CountedCompleter<?> c;
5688	+	for (c = firstComplete(); c != null; c = c.nextComplete()) {
5689	+	@SuppressWarnings("unchecked")
5690	+	MapReduceMappingsTask<K,V,U>
5691	+	t = (MapReduceMappingsTask<K,V,U>)c,
5692	+	s = t.rights;
5693	+	while (s != null) {
5694	+	U tr, sr;
5695	+	if ((sr = s.result) != null)
5696	+	t.result = (((tr = t.result) == null) ? sr :
5697	+	reducer.apply(tr, sr));
5698	+	s = t.rights = s.nextRight;
5699	+	}
5700	+	}
5701	+	}
5702	+	}
5703	+	}
5704	+
5705	+	@SuppressWarnings("serial")
5706	+	static final class MapReduceKeysToDoubleTask<K,V>
5707	+	extends BulkTask<K,V,Double> {
5708	+	final ToDoubleFunction<? super K> transformer;
5709	+	final DoubleBinaryOperator reducer;
5710	+	final double basis;
5711	+	double result;
5712	+	MapReduceKeysToDoubleTask<K,V> rights, nextRight;
5713	+	MapReduceKeysToDoubleTask
5714	+	(BulkTask<K,V,?> p, int b, int i, int f, Node<K,V>[] t,
5715	+	MapReduceKeysToDoubleTask<K,V> nextRight,
5716	+	ToDoubleFunction<? super K> transformer,
5717	+	double basis,
5718	+	DoubleBinaryOperator reducer) {
5719	+	super(p, b, i, f, t); this.nextRight = nextRight;
5720	+	this.transformer = transformer;
5721	+	this.basis = basis; this.reducer = reducer;
5722	+	}
5723	+	public final Double getRawResult() { return result; }
5724	+	public final void compute() {
5725	+	final ToDoubleFunction<? super K> transformer;
5726	+	final DoubleBinaryOperator reducer;
5727	+	if ((transformer = this.transformer) != null &&
5728	+	(reducer = this.reducer) != null) {
5729	+	double r = this.basis;
5730	+	for (int i = baseIndex, f, h; batch > 0 &&
5731	+	(h = ((f = baseLimit) + i) >>> 1) > i;) {
5732	+	addToPendingCount(1);
5733	+	(rights = new MapReduceKeysToDoubleTask<K,V>
5734	+	(this, batch >>>= 1, baseLimit = h, f, tab,
5735	+	rights, transformer, r, reducer)).fork();
5736	+	}
5737	+	for (Node<K,V> p; (p = advance()) != null; )
5738	+	r = reducer.applyAsDouble(r, transformer.applyAsDouble(p.key));
5739	+	result = r;
5740	+	CountedCompleter<?> c;
5741	+	for (c = firstComplete(); c != null; c = c.nextComplete()) {
5742	+	@SuppressWarnings("unchecked")
5743	+	MapReduceKeysToDoubleTask<K,V>
5744	+	t = (MapReduceKeysToDoubleTask<K,V>)c,
5745	+	s = t.rights;
5746	+	while (s != null) {
5747	+	t.result = reducer.applyAsDouble(t.result, s.result);
5748	+	s = t.rights = s.nextRight;
5749	+	}
5750	+	}
5751	+	}
5752	+	}
5753	+	}
5754	+
5755	+	@SuppressWarnings("serial")
5756	+	static final class MapReduceValuesToDoubleTask<K,V>
5757	+	extends BulkTask<K,V,Double> {
5758	+	final ToDoubleFunction<? super V> transformer;
5759	+	final DoubleBinaryOperator reducer;
5760	+	final double basis;
5761	+	double result;
5762	+	MapReduceValuesToDoubleTask<K,V> rights, nextRight;
5763	+	MapReduceValuesToDoubleTask
5764	+	(BulkTask<K,V,?> p, int b, int i, int f, Node<K,V>[] t,
5765	+	MapReduceValuesToDoubleTask<K,V> nextRight,
5766	+	ToDoubleFunction<? super V> transformer,
5767	+	double basis,
5768	+	DoubleBinaryOperator reducer) {
5769	+	super(p, b, i, f, t); this.nextRight = nextRight;
5770	+	this.transformer = transformer;
5771	+	this.basis = basis; this.reducer = reducer;
5772	+	}
5773	+	public final Double getRawResult() { return result; }
5774	+	public final void compute() {
5775	+	final ToDoubleFunction<? super V> transformer;
5776	+	final DoubleBinaryOperator reducer;
5777	+	if ((transformer = this.transformer) != null &&
5778	+	(reducer = this.reducer) != null) {
5779	+	double r = this.basis;
5780	+	for (int i = baseIndex, f, h; batch > 0 &&
5781	+	(h = ((f = baseLimit) + i) >>> 1) > i;) {
5782	+	addToPendingCount(1);
5783	+	(rights = new MapReduceValuesToDoubleTask<K,V>
5784	+	(this, batch >>>= 1, baseLimit = h, f, tab,
5785	+	rights, transformer, r, reducer)).fork();
5786	+	}
5787	+	for (Node<K,V> p; (p = advance()) != null; )
5788	+	r = reducer.applyAsDouble(r, transformer.applyAsDouble(p.val));
5789	+	result = r;
5790	+	CountedCompleter<?> c;
5791	+	for (c = firstComplete(); c != null; c = c.nextComplete()) {
5792	+	@SuppressWarnings("unchecked")
5793	+	MapReduceValuesToDoubleTask<K,V>
5794	+	t = (MapReduceValuesToDoubleTask<K,V>)c,
5795	+	s = t.rights;
5796	+	while (s != null) {
5797	+	t.result = reducer.applyAsDouble(t.result, s.result);
5798	+	s = t.rights = s.nextRight;
5799	+	}
5800	+	}
5801	+	}
5802	+	}
5803	+	}
5804	+
5805	+	@SuppressWarnings("serial")
5806	+	static final class MapReduceEntriesToDoubleTask<K,V>
5807	+	extends BulkTask<K,V,Double> {
5808	+	final ToDoubleFunction<Map.Entry<K,V>> transformer;
5809	+	final DoubleBinaryOperator reducer;
5810	+	final double basis;
5811	+	double result;
5812	+	MapReduceEntriesToDoubleTask<K,V> rights, nextRight;
5813	+	MapReduceEntriesToDoubleTask
5814	+	(BulkTask<K,V,?> p, int b, int i, int f, Node<K,V>[] t,
5815	+	MapReduceEntriesToDoubleTask<K,V> nextRight,
5816	+	ToDoubleFunction<Map.Entry<K,V>> transformer,
5817	+	double basis,
5818	+	DoubleBinaryOperator reducer) {
5819	+	super(p, b, i, f, t); this.nextRight = nextRight;
5820	+	this.transformer = transformer;
5821	+	this.basis = basis; this.reducer = reducer;
5822	+	}
5823	+	public final Double getRawResult() { return result; }
5824	+	public final void compute() {
5825	+	final ToDoubleFunction<Map.Entry<K,V>> transformer;
5826	+	final DoubleBinaryOperator reducer;
5827	+	if ((transformer = this.transformer) != null &&
5828	+	(reducer = this.reducer) != null) {
5829	+	double r = this.basis;
5830	+	for (int i = baseIndex, f, h; batch > 0 &&
5831	+	(h = ((f = baseLimit) + i) >>> 1) > i;) {
5832	+	addToPendingCount(1);
5833	+	(rights = new MapReduceEntriesToDoubleTask<K,V>
5834	+	(this, batch >>>= 1, baseLimit = h, f, tab,
5835	+	rights, transformer, r, reducer)).fork();
5836	+	}
5837	+	for (Node<K,V> p; (p = advance()) != null; )
5838	+	r = reducer.applyAsDouble(r, transformer.applyAsDouble(p));
5839	+	result = r;
5840	+	CountedCompleter<?> c;
5841	+	for (c = firstComplete(); c != null; c = c.nextComplete()) {
5842	+	@SuppressWarnings("unchecked")
5843	+	MapReduceEntriesToDoubleTask<K,V>
5844	+	t = (MapReduceEntriesToDoubleTask<K,V>)c,
5845	+	s = t.rights;
5846	+	while (s != null) {
5847	+	t.result = reducer.applyAsDouble(t.result, s.result);
5848	+	s = t.rights = s.nextRight;
5849	+	}
5850	+	}
5851	+	}
5852	+	}
5853	+	}
5854	+
5855	+	@SuppressWarnings("serial")
5856	+	static final class MapReduceMappingsToDoubleTask<K,V>
5857	+	extends BulkTask<K,V,Double> {
5858	+	final ToDoubleBiFunction<? super K, ? super V> transformer;
5859	+	final DoubleBinaryOperator reducer;
5860	+	final double basis;
5861	+	double result;
5862	+	MapReduceMappingsToDoubleTask<K,V> rights, nextRight;
5863	+	MapReduceMappingsToDoubleTask
5864	+	(BulkTask<K,V,?> p, int b, int i, int f, Node<K,V>[] t,
5865	+	MapReduceMappingsToDoubleTask<K,V> nextRight,
5866	+	ToDoubleBiFunction<? super K, ? super V> transformer,
5867	+	double basis,
5868	+	DoubleBinaryOperator reducer) {
5869	+	super(p, b, i, f, t); this.nextRight = nextRight;
5870	+	this.transformer = transformer;
5871	+	this.basis = basis; this.reducer = reducer;
5872	+	}
5873	+	public final Double getRawResult() { return result; }
5874	+	public final void compute() {
5875	+	final ToDoubleBiFunction<? super K, ? super V> transformer;
5876	+	final DoubleBinaryOperator reducer;
5877	+	if ((transformer = this.transformer) != null &&
5878	+	(reducer = this.reducer) != null) {
5879	+	double r = this.basis;
5880	+	for (int i = baseIndex, f, h; batch > 0 &&
5881	+	(h = ((f = baseLimit) + i) >>> 1) > i;) {
5882	+	addToPendingCount(1);
5883	+	(rights = new MapReduceMappingsToDoubleTask<K,V>
5884	+	(this, batch >>>= 1, baseLimit = h, f, tab,
5885	+	rights, transformer, r, reducer)).fork();
5886	+	}
5887	+	for (Node<K,V> p; (p = advance()) != null; )
5888	+	r = reducer.applyAsDouble(r, transformer.applyAsDouble(p.key, p.val));
5889	+	result = r;
5890	+	CountedCompleter<?> c;
5891	+	for (c = firstComplete(); c != null; c = c.nextComplete()) {
5892	+	@SuppressWarnings("unchecked")
5893	+	MapReduceMappingsToDoubleTask<K,V>
5894	+	t = (MapReduceMappingsToDoubleTask<K,V>)c,
5895	+	s = t.rights;
5896	+	while (s != null) {
5897	+	t.result = reducer.applyAsDouble(t.result, s.result);
5898	+	s = t.rights = s.nextRight;
5899	+	}
5900	+	}
5901	+	}
5902	+	}
5903	+	}
5904	+
5905	+	@SuppressWarnings("serial")
5906	+	static final class MapReduceKeysToLongTask<K,V>
5907	+	extends BulkTask<K,V,Long> {
5908	+	final ToLongFunction<? super K> transformer;
5909	+	final LongBinaryOperator reducer;
5910	+	final long basis;
5911	+	long result;
5912	+	MapReduceKeysToLongTask<K,V> rights, nextRight;
5913	+	MapReduceKeysToLongTask
5914	+	(BulkTask<K,V,?> p, int b, int i, int f, Node<K,V>[] t,
5915	+	MapReduceKeysToLongTask<K,V> nextRight,
5916	+	ToLongFunction<? super K> transformer,
5917	+	long basis,
5918	+	LongBinaryOperator reducer) {
5919	+	super(p, b, i, f, t); this.nextRight = nextRight;
5920	+	this.transformer = transformer;
5921	+	this.basis = basis; this.reducer = reducer;
5922	+	}
5923	+	public final Long getRawResult() { return result; }
5924	+	public final void compute() {
5925	+	final ToLongFunction<? super K> transformer;
5926	+	final LongBinaryOperator reducer;
5927	+	if ((transformer = this.transformer) != null &&
5928	+	(reducer = this.reducer) != null) {
5929	+	long r = this.basis;
5930	+	for (int i = baseIndex, f, h; batch > 0 &&
5931	+	(h = ((f = baseLimit) + i) >>> 1) > i;) {
5932	+	addToPendingCount(1);
5933	+	(rights = new MapReduceKeysToLongTask<K,V>
5934	+	(this, batch >>>= 1, baseLimit = h, f, tab,
5935	+	rights, transformer, r, reducer)).fork();
5936	+	}
5937	+	for (Node<K,V> p; (p = advance()) != null; )
5938	+	r = reducer.applyAsLong(r, transformer.applyAsLong(p.key));
5939	+	result = r;
5940	+	CountedCompleter<?> c;
5941	+	for (c = firstComplete(); c != null; c = c.nextComplete()) {
5942	+	@SuppressWarnings("unchecked")
5943	+	MapReduceKeysToLongTask<K,V>
5944	+	t = (MapReduceKeysToLongTask<K,V>)c,
5945	+	s = t.rights;
5946	+	while (s != null) {
5947	+	t.result = reducer.applyAsLong(t.result, s.result);
5948	+	s = t.rights = s.nextRight;
5949	+	}
5950	+	}
5951	+	}
5952	+	}
5953	+	}
5954	+
5955	+	@SuppressWarnings("serial")
5956	+	static final class MapReduceValuesToLongTask<K,V>
5957	+	extends BulkTask<K,V,Long> {
5958	+	final ToLongFunction<? super V> transformer;
5959	+	final LongBinaryOperator reducer;
5960	+	final long basis;
5961	+	long result;
5962	+	MapReduceValuesToLongTask<K,V> rights, nextRight;
5963	+	MapReduceValuesToLongTask
5964	+	(BulkTask<K,V,?> p, int b, int i, int f, Node<K,V>[] t,
5965	+	MapReduceValuesToLongTask<K,V> nextRight,
5966	+	ToLongFunction<? super V> transformer,
5967	+	long basis,
5968	+	LongBinaryOperator reducer) {
5969	+	super(p, b, i, f, t); this.nextRight = nextRight;
5970	+	this.transformer = transformer;
5971	+	this.basis = basis; this.reducer = reducer;
5972	+	}
5973	+	public final Long getRawResult() { return result; }
5974	+	public final void compute() {
5975	+	final ToLongFunction<? super V> transformer;
5976	+	final LongBinaryOperator reducer;
5977	+	if ((transformer = this.transformer) != null &&
5978	+	(reducer = this.reducer) != null) {
5979	+	long r = this.basis;
5980	+	for (int i = baseIndex, f, h; batch > 0 &&
5981	+	(h = ((f = baseLimit) + i) >>> 1) > i;) {
5982	+	addToPendingCount(1);
5983	+	(rights = new MapReduceValuesToLongTask<K,V>
5984	+	(this, batch >>>= 1, baseLimit = h, f, tab,
5985	+	rights, transformer, r, reducer)).fork();
5986	+	}
5987	+	for (Node<K,V> p; (p = advance()) != null; )
5988	+	r = reducer.applyAsLong(r, transformer.applyAsLong(p.val));
5989	+	result = r;
5990	+	CountedCompleter<?> c;
5991	+	for (c = firstComplete(); c != null; c = c.nextComplete()) {
5992	+	@SuppressWarnings("unchecked")
5993	+	MapReduceValuesToLongTask<K,V>
5994	+	t = (MapReduceValuesToLongTask<K,V>)c,
5995	+	s = t.rights;
5996	+	while (s != null) {
5997	+	t.result = reducer.applyAsLong(t.result, s.result);
5998	+	s = t.rights = s.nextRight;
5999	+	}
6000	+	}
6001	+	}
6002	+	}
6003	+	}
6004	+
6005	+	@SuppressWarnings("serial")
6006	+	static final class MapReduceEntriesToLongTask<K,V>
6007	+	extends BulkTask<K,V,Long> {
6008	+	final ToLongFunction<Map.Entry<K,V>> transformer;
6009	+	final LongBinaryOperator reducer;
6010	+	final long basis;
6011	+	long result;
6012	+	MapReduceEntriesToLongTask<K,V> rights, nextRight;
6013	+	MapReduceEntriesToLongTask
6014	+	(BulkTask<K,V,?> p, int b, int i, int f, Node<K,V>[] t,
6015	+	MapReduceEntriesToLongTask<K,V> nextRight,
6016	+	ToLongFunction<Map.Entry<K,V>> transformer,
6017	+	long basis,
6018	+	LongBinaryOperator reducer) {
6019	+	super(p, b, i, f, t); this.nextRight = nextRight;
6020	+	this.transformer = transformer;
6021	+	this.basis = basis; this.reducer = reducer;
6022	+	}
6023	+	public final Long getRawResult() { return result; }
6024	+	public final void compute() {
6025	+	final ToLongFunction<Map.Entry<K,V>> transformer;
6026	+	final LongBinaryOperator reducer;
6027	+	if ((transformer = this.transformer) != null &&
6028	+	(reducer = this.reducer) != null) {
6029	+	long r = this.basis;
6030	+	for (int i = baseIndex, f, h; batch > 0 &&
6031	+	(h = ((f = baseLimit) + i) >>> 1) > i;) {
6032	+	addToPendingCount(1);
6033	+	(rights = new MapReduceEntriesToLongTask<K,V>
6034	+	(this, batch >>>= 1, baseLimit = h, f, tab,
6035	+	rights, transformer, r, reducer)).fork();
6036	+	}
6037	+	for (Node<K,V> p; (p = advance()) != null; )
6038	+	r = reducer.applyAsLong(r, transformer.applyAsLong(p));
6039	+	result = r;
6040	+	CountedCompleter<?> c;
6041	+	for (c = firstComplete(); c != null; c = c.nextComplete()) {
6042	+	@SuppressWarnings("unchecked")
6043	+	MapReduceEntriesToLongTask<K,V>
6044	+	t = (MapReduceEntriesToLongTask<K,V>)c,
6045	+	s = t.rights;
6046	+	while (s != null) {
6047	+	t.result = reducer.applyAsLong(t.result, s.result);
6048	+	s = t.rights = s.nextRight;
6049	+	}
6050	+	}
6051	+	}
6052	+	}
6053	+	}
6054	+
6055	+	@SuppressWarnings("serial")
6056	+	static final class MapReduceMappingsToLongTask<K,V>
6057	+	extends BulkTask<K,V,Long> {
6058	+	final ToLongBiFunction<? super K, ? super V> transformer;
6059	+	final LongBinaryOperator reducer;
6060	+	final long basis;
6061	+	long result;
6062	+	MapReduceMappingsToLongTask<K,V> rights, nextRight;
6063	+	MapReduceMappingsToLongTask
6064	+	(BulkTask<K,V,?> p, int b, int i, int f, Node<K,V>[] t,
6065	+	MapReduceMappingsToLongTask<K,V> nextRight,
6066	+	ToLongBiFunction<? super K, ? super V> transformer,
6067	+	long basis,
6068	+	LongBinaryOperator reducer) {
6069	+	super(p, b, i, f, t); this.nextRight = nextRight;
6070	+	this.transformer = transformer;
6071	+	this.basis = basis; this.reducer = reducer;
6072	+	}
6073	+	public final Long getRawResult() { return result; }
6074	+	public final void compute() {
6075	+	final ToLongBiFunction<? super K, ? super V> transformer;
6076	+	final LongBinaryOperator reducer;
6077	+	if ((transformer = this.transformer) != null &&
6078	+	(reducer = this.reducer) != null) {
6079	+	long r = this.basis;
6080	+	for (int i = baseIndex, f, h; batch > 0 &&
6081	+	(h = ((f = baseLimit) + i) >>> 1) > i;) {
6082	+	addToPendingCount(1);
6083	+	(rights = new MapReduceMappingsToLongTask<K,V>
6084	+	(this, batch >>>= 1, baseLimit = h, f, tab,
6085	+	rights, transformer, r, reducer)).fork();
6086	+	}
6087	+	for (Node<K,V> p; (p = advance()) != null; )
6088	+	r = reducer.applyAsLong(r, transformer.applyAsLong(p.key, p.val));
6089	+	result = r;
6090	+	CountedCompleter<?> c;
6091	+	for (c = firstComplete(); c != null; c = c.nextComplete()) {
6092	+	@SuppressWarnings("unchecked")
6093	+	MapReduceMappingsToLongTask<K,V>
6094	+	t = (MapReduceMappingsToLongTask<K,V>)c,
6095	+	s = t.rights;
6096	+	while (s != null) {
6097	+	t.result = reducer.applyAsLong(t.result, s.result);
6098	+	s = t.rights = s.nextRight;
6099	+	}
6100	+	}
6101	+	}
6102	+	}
6103	+	}
6104	+
6105	+	@SuppressWarnings("serial")
6106	+	static final class MapReduceKeysToIntTask<K,V>
6107	+	extends BulkTask<K,V,Integer> {
6108	+	final ToIntFunction<? super K> transformer;
6109	+	final IntBinaryOperator reducer;
6110	+	final int basis;
6111	+	int result;
6112	+	MapReduceKeysToIntTask<K,V> rights, nextRight;
6113	+	MapReduceKeysToIntTask
6114	+	(BulkTask<K,V,?> p, int b, int i, int f, Node<K,V>[] t,
6115	+	MapReduceKeysToIntTask<K,V> nextRight,
6116	+	ToIntFunction<? super K> transformer,
6117	+	int basis,
6118	+	IntBinaryOperator reducer) {
6119	+	super(p, b, i, f, t); this.nextRight = nextRight;
6120	+	this.transformer = transformer;
6121	+	this.basis = basis; this.reducer = reducer;
6122	+	}
6123	+	public final Integer getRawResult() { return result; }
6124	+	public final void compute() {
6125	+	final ToIntFunction<? super K> transformer;
6126	+	final IntBinaryOperator reducer;
6127	+	if ((transformer = this.transformer) != null &&
6128	+	(reducer = this.reducer) != null) {
6129	+	int r = this.basis;
6130	+	for (int i = baseIndex, f, h; batch > 0 &&
6131	+	(h = ((f = baseLimit) + i) >>> 1) > i;) {
6132	+	addToPendingCount(1);
6133	+	(rights = new MapReduceKeysToIntTask<K,V>
6134	+	(this, batch >>>= 1, baseLimit = h, f, tab,
6135	+	rights, transformer, r, reducer)).fork();
6136	+	}
6137	+	for (Node<K,V> p; (p = advance()) != null; )
6138	+	r = reducer.applyAsInt(r, transformer.applyAsInt(p.key));
6139	+	result = r;
6140	+	CountedCompleter<?> c;
6141	+	for (c = firstComplete(); c != null; c = c.nextComplete()) {
6142	+	@SuppressWarnings("unchecked")
6143	+	MapReduceKeysToIntTask<K,V>
6144	+	t = (MapReduceKeysToIntTask<K,V>)c,
6145	+	s = t.rights;
6146	+	while (s != null) {
6147	+	t.result = reducer.applyAsInt(t.result, s.result);
6148	+	s = t.rights = s.nextRight;
6149	+	}
6150	+	}
6151	+	}
6152	+	}
6153	+	}
6154	+
6155	+	@SuppressWarnings("serial")
6156	+	static final class MapReduceValuesToIntTask<K,V>
6157	+	extends BulkTask<K,V,Integer> {
6158	+	final ToIntFunction<? super V> transformer;
6159	+	final IntBinaryOperator reducer;
6160	+	final int basis;
6161	+	int result;
6162	+	MapReduceValuesToIntTask<K,V> rights, nextRight;
6163	+	MapReduceValuesToIntTask
6164	+	(BulkTask<K,V,?> p, int b, int i, int f, Node<K,V>[] t,
6165	+	MapReduceValuesToIntTask<K,V> nextRight,
6166	+	ToIntFunction<? super V> transformer,
6167	+	int basis,
6168	+	IntBinaryOperator reducer) {
6169	+	super(p, b, i, f, t); this.nextRight = nextRight;
6170	+	this.transformer = transformer;
6171	+	this.basis = basis; this.reducer = reducer;
6172	+	}
6173	+	public final Integer getRawResult() { return result; }
6174	+	public final void compute() {
6175	+	final ToIntFunction<? super V> transformer;
6176	+	final IntBinaryOperator reducer;
6177	+	if ((transformer = this.transformer) != null &&
6178	+	(reducer = this.reducer) != null) {
6179	+	int r = this.basis;
6180	+	for (int i = baseIndex, f, h; batch > 0 &&
6181	+	(h = ((f = baseLimit) + i) >>> 1) > i;) {
6182	+	addToPendingCount(1);
6183	+	(rights = new MapReduceValuesToIntTask<K,V>
6184	+	(this, batch >>>= 1, baseLimit = h, f, tab,
6185	+	rights, transformer, r, reducer)).fork();
6186	+	}
6187	+	for (Node<K,V> p; (p = advance()) != null; )
6188	+	r = reducer.applyAsInt(r, transformer.applyAsInt(p.val));
6189	+	result = r;
6190	+	CountedCompleter<?> c;
6191	+	for (c = firstComplete(); c != null; c = c.nextComplete()) {
6192	+	@SuppressWarnings("unchecked")
6193	+	MapReduceValuesToIntTask<K,V>
6194	+	t = (MapReduceValuesToIntTask<K,V>)c,
6195	+	s = t.rights;
6196	+	while (s != null) {
6197	+	t.result = reducer.applyAsInt(t.result, s.result);
6198	+	s = t.rights = s.nextRight;
6199	+	}
6200	+	}
6201	+	}
6202	+	}
6203	+	}
6204	+
6205	+	@SuppressWarnings("serial")
6206	+	static final class MapReduceEntriesToIntTask<K,V>
6207	+	extends BulkTask<K,V,Integer> {
6208	+	final ToIntFunction<Map.Entry<K,V>> transformer;
6209	+	final IntBinaryOperator reducer;
6210	+	final int basis;
6211	+	int result;
6212	+	MapReduceEntriesToIntTask<K,V> rights, nextRight;
6213	+	MapReduceEntriesToIntTask
6214	+	(BulkTask<K,V,?> p, int b, int i, int f, Node<K,V>[] t,
6215	+	MapReduceEntriesToIntTask<K,V> nextRight,
6216	+	ToIntFunction<Map.Entry<K,V>> transformer,
6217	+	int basis,
6218	+	IntBinaryOperator reducer) {
6219	+	super(p, b, i, f, t); this.nextRight = nextRight;
6220	+	this.transformer = transformer;
6221	+	this.basis = basis; this.reducer = reducer;
6222	+	}
6223	+	public final Integer getRawResult() { return result; }
6224	+	public final void compute() {
6225	+	final ToIntFunction<Map.Entry<K,V>> transformer;
6226	+	final IntBinaryOperator reducer;
6227	+	if ((transformer = this.transformer) != null &&
6228	+	(reducer = this.reducer) != null) {
6229	+	int r = this.basis;
6230	+	for (int i = baseIndex, f, h; batch > 0 &&
6231	+	(h = ((f = baseLimit) + i) >>> 1) > i;) {
6232	+	addToPendingCount(1);
6233	+	(rights = new MapReduceEntriesToIntTask<K,V>
6234	+	(this, batch >>>= 1, baseLimit = h, f, tab,
6235	+	rights, transformer, r, reducer)).fork();
6236	+	}
6237	+	for (Node<K,V> p; (p = advance()) != null; )
6238	+	r = reducer.applyAsInt(r, transformer.applyAsInt(p));
6239	+	result = r;
6240	+	CountedCompleter<?> c;
6241	+	for (c = firstComplete(); c != null; c = c.nextComplete()) {
6242	+	@SuppressWarnings("unchecked")
6243	+	MapReduceEntriesToIntTask<K,V>
6244	+	t = (MapReduceEntriesToIntTask<K,V>)c,
6245	+	s = t.rights;
6246	+	while (s != null) {
6247	+	t.result = reducer.applyAsInt(t.result, s.result);
6248	+	s = t.rights = s.nextRight;
6249	+	}
6250	+	}
6251	+	}
6252	+	}
6253	+	}
6254	+
6255	+	@SuppressWarnings("serial")
6256	+	static final class MapReduceMappingsToIntTask<K,V>
6257	+	extends BulkTask<K,V,Integer> {
6258	+	final ToIntBiFunction<? super K, ? super V> transformer;
6259	+	final IntBinaryOperator reducer;
6260	+	final int basis;
6261	+	int result;
6262	+	MapReduceMappingsToIntTask<K,V> rights, nextRight;
6263	+	MapReduceMappingsToIntTask
6264	+	(BulkTask<K,V,?> p, int b, int i, int f, Node<K,V>[] t,
6265	+	MapReduceMappingsToIntTask<K,V> nextRight,
6266	+	ToIntBiFunction<? super K, ? super V> transformer,
6267	+	int basis,
6268	+	IntBinaryOperator reducer) {
6269	+	super(p, b, i, f, t); this.nextRight = nextRight;
6270	+	this.transformer = transformer;
6271	+	this.basis = basis; this.reducer = reducer;
6272	+	}
6273	+	public final Integer getRawResult() { return result; }
6274	+	public final void compute() {
6275	+	final ToIntBiFunction<? super K, ? super V> transformer;
6276	+	final IntBinaryOperator reducer;
6277	+	if ((transformer = this.transformer) != null &&
6278	+	(reducer = this.reducer) != null) {
6279	+	int r = this.basis;
6280	+	for (int i = baseIndex, f, h; batch > 0 &&
6281	+	(h = ((f = baseLimit) + i) >>> 1) > i;) {
6282	+	addToPendingCount(1);
6283	+	(rights = new MapReduceMappingsToIntTask<K,V>
6284	+	(this, batch >>>= 1, baseLimit = h, f, tab,
6285	+	rights, transformer, r, reducer)).fork();
6286	+	}
6287	+	for (Node<K,V> p; (p = advance()) != null; )
6288	+	r = reducer.applyAsInt(r, transformer.applyAsInt(p.key, p.val));
6289	+	result = r;
6290	+	CountedCompleter<?> c;
6291	+	for (c = firstComplete(); c != null; c = c.nextComplete()) {
6292	+	@SuppressWarnings("unchecked")
6293	+	MapReduceMappingsToIntTask<K,V>
6294	+	t = (MapReduceMappingsToIntTask<K,V>)c,
6295	+	s = t.rights;
6296	+	while (s != null) {
6297	+	t.result = reducer.applyAsInt(t.result, s.result);
6298	+	s = t.rights = s.nextRight;
6299	+	}
6300	+	}
6301	+	}
6302	+	}
6303	+	}
6304	+
6305	+	// Unsafe mechanics
6306	+	private static final sun.misc.Unsafe U = sun.misc.Unsafe.getUnsafe();
6307	+	private static final long SIZECTL;
6308	+	private static final long TRANSFERINDEX;
6309	+	private static final long BASECOUNT;
6310	+	private static final long CELLSBUSY;
6311	+	private static final long CELLVALUE;
6312	+	private static final int ABASE;
6313	+	private static final int ASHIFT;
6314	+
6315	+	static {
6316	+	try {
6317	+	SIZECTL = U.objectFieldOffset
6318	+	(ConcurrentHashMap.class.getDeclaredField("sizeCtl"));
6319	+	TRANSFERINDEX = U.objectFieldOffset
6320	+	(ConcurrentHashMap.class.getDeclaredField("transferIndex"));
6321	+	BASECOUNT = U.objectFieldOffset
6322	+	(ConcurrentHashMap.class.getDeclaredField("baseCount"));
6323	+	CELLSBUSY = U.objectFieldOffset
6324	+	(ConcurrentHashMap.class.getDeclaredField("cellsBusy"));
6325	+
6326	+	CELLVALUE = U.objectFieldOffset
6327	+	(CounterCell.class.getDeclaredField("value"));
6328	+
6329	+	ABASE = U.arrayBaseOffset(Node[].class);
6330	+	int scale = U.arrayIndexScale(Node[].class);
6331	+	if ((scale & (scale - 1)) != 0)
6332	+	throw new Error("array index scale not a power of two");
6333	+	ASHIFT = 31 - Integer.numberOfLeadingZeros(scale);
6334	+	} catch (ReflectiveOperationException e) {
6335	+	throw new Error(e);
6336	+	}
6337	+
6338	+	// Reduce the risk of rare disastrous classloading in first call to
6339	+	// LockSupport.park: https://bugs.openjdk.java.net/browse/JDK-8074773
6340	+	Class<?> ensureLoaded = LockSupport.class;
6341	+	}
6342		}

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