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Comparing jsr166/src/main/java/util/concurrent/ConcurrentHashMap.java (file contents):
Revision 1.112 by jsr166, Fri Jun 3 02:28:05 2011 UTC vs.
Revision 1.126 by dl, Tue Aug 14 13:16:54 2012 UTC

#	Line 5 | Line 5
5		*/
6
7		package java.util.concurrent;
8	<	import java.util.concurrent.locks.*;
9	<	import java.util.*;
8	>	import java.util.concurrent.atomic.LongAdder;
9	>	import java.util.concurrent.ForkJoinPool;
10	>	import java.util.concurrent.ForkJoinTask;
11	>
12	>	import java.util.Comparator;
13	>	import java.util.Arrays;
14	>	import java.util.Map;
15	>	import java.util.Set;
16	>	import java.util.Collection;
17	>	import java.util.AbstractMap;
18	>	import java.util.AbstractSet;
19	>	import java.util.AbstractCollection;
20	>	import java.util.Hashtable;
21	>	import java.util.HashMap;
22	>	import java.util.Iterator;
23	>	import java.util.Enumeration;
24	>	import java.util.ConcurrentModificationException;
25	>	import java.util.NoSuchElementException;
26	>	import java.util.concurrent.ConcurrentMap;
27	>	import java.util.concurrent.ThreadLocalRandom;
28	>	import java.util.concurrent.locks.LockSupport;
29	>	import java.util.concurrent.locks.AbstractQueuedSynchronizer;
30	>	import java.util.concurrent.atomic.AtomicReference;
31	>
32		import java.io.Serializable;
11	–	import java.io.IOException;
12	–	import java.io.ObjectInputStream;
13	–	import java.io.ObjectOutputStream;
33
34		/**
35		* A hash table supporting full concurrency of retrievals and
36	<	* adjustable expected concurrency for updates. This class obeys the
36	>	* high expected concurrency for updates. This class obeys the
37		* same functional specification as {@link java.util.Hashtable}, and
38		* includes versions of methods corresponding to each method of
39	<	* <tt>Hashtable</tt>. However, even though all operations are
39	>	* {@code Hashtable}. However, even though all operations are
40		* thread-safe, retrieval operations do <em>not</em> entail locking,
41		* and there is <em>not</em> any support for locking the entire table
42		* in a way that prevents all access.  This class is fully
43	<	* interoperable with <tt>Hashtable</tt> in programs that rely on its
43	>	* interoperable with {@code Hashtable} in programs that rely on its
44		* thread safety but not on its synchronization details.
45		*
46	<	* <p> Retrieval operations (including <tt>get</tt>) generally do not
47	<	* block, so may overlap with update operations (including
48	<	* <tt>put</tt> and <tt>remove</tt>). Retrievals reflect the results
49	<	* of the most recently <em>completed</em> update operations holding
50	<	* upon their onset.  For aggregate operations such as <tt>putAll</tt>
51	<	* and <tt>clear</tt>, concurrent retrievals may reflect insertion or
52	<	* removal of only some entries.  Similarly, Iterators and
53	<	* Enumerations return elements reflecting the state of the hash table
54	<	* at some point at or since the creation of the iterator/enumeration.
55	<	* They do <em>not</em> throw {@link ConcurrentModificationException}.
56	<	* However, iterators are designed to be used by only one thread at a time.
46	>	* <p> Retrieval operations (including {@code get}) generally do not
47	>	* block, so may overlap with update operations (including {@code put}
48	>	* and {@code remove}). Retrievals reflect the results of the most
49	>	* recently <em>completed</em> update operations holding upon their
50	>	* onset. (More formally, an update operation for a given key bears a
51	>	* <em>happens-before</em> relation with any (non-null) retrieval for
52	>	* that key reporting the updated value.)  For aggregate operations
53	>	* such as {@code putAll} and {@code clear}, concurrent retrievals may
54	>	* reflect insertion or removal of only some entries.  Similarly,
55	>	* Iterators and Enumerations return elements reflecting the state of
56	>	* the hash table at some point at or since the creation of the
57	>	* iterator/enumeration.  They do <em>not</em> throw {@link
58	>	* ConcurrentModificationException}.  However, iterators are designed
59	>	* to be used by only one thread at a time.  Bear in mind that the
60	>	* results of aggregate status methods including {@code size}, {@code
61	>	* isEmpty}, and {@code containsValue} are typically useful only when
62	>	* a map is not undergoing concurrent updates in other threads.
63	>	* Otherwise the results of these methods reflect transient states
64	>	* that may be adequate for monitoring or estimation purposes, but not
65	>	* for program control.
66		*
67	<	* <p> The allowed concurrency among update operations is guided by
68	<	* the optional <tt>concurrencyLevel</tt> constructor argument
69	<	* (default <tt>16</tt>), which is used as a hint for internal sizing.  The
70	<	* table is internally partitioned to try to permit the indicated
71	<	* number of concurrent updates without contention. Because placement
72	<	* in hash tables is essentially random, the actual concurrency will
73	<	* vary.  Ideally, you should choose a value to accommodate as many
74	<	* threads as will ever concurrently modify the table. Using a
75	<	* significantly higher value than you need can waste space and time,
76	<	* and a significantly lower value can lead to thread contention. But
77	<	* overestimates and underestimates within an order of magnitude do
78	<	* not usually have much noticeable impact. A value of one is
79	<	* appropriate when it is known that only one thread will modify and
80	<	* all others will only read. Also, resizing this or any other kind of
81	<	* hash table is a relatively slow operation, so, when possible, it is
82	<	* a good idea to provide estimates of expected table sizes in
83	<	* constructors.
67	>	* <p> The table is dynamically expanded when there are too many
68	>	* collisions (i.e., keys that have distinct hash codes but fall into
69	>	* the same slot modulo the table size), with the expected average
70	>	* effect of maintaining roughly two bins per mapping (corresponding
71	>	* to a 0.75 load factor threshold for resizing). There may be much
72	>	* variance around this average as mappings are added and removed, but
73	>	* overall, this maintains a commonly accepted time/space tradeoff for
74	>	* hash tables.  However, resizing this or any other kind of hash
75	>	* table may be a relatively slow operation. When possible, it is a
76	>	* good idea to provide a size estimate as an optional {@code
77	>	* initialCapacity} constructor argument. An additional optional
78	>	* {@code loadFactor} constructor argument provides a further means of
79	>	* customizing initial table capacity by specifying the table density
80	>	* to be used in calculating the amount of space to allocate for the
81	>	* given number of elements.  Also, for compatibility with previous
82	>	* versions of this class, constructors may optionally specify an
83	>	* expected {@code concurrencyLevel} as an additional hint for
84	>	* internal sizing.  Note that using many keys with exactly the same
85	>	* {@code hashCode()} is a sure way to slow down performance of any
86	>	* hash table.
87		*
88		* <p>This class and its views and iterators implement all of the
89		* <em>optional</em> methods of the {@link Map} and {@link Iterator}
90		* interfaces.
91		*
92		* <p> Like {@link Hashtable} but unlike {@link HashMap}, this class
93	<	* does <em>not</em> allow <tt>null</tt> to be used as a key or value.
93	>	* does <em>not</em> allow {@code null} to be used as a key or value.
94		*
95		* <p>This class is a member of the
96		* <a href="{@docRoot}/../technotes/guides/collections/index.html">
97		* Java Collections Framework</a>.
98		*
99	+	* <p><em>jsr166e note: This class is a candidate replacement for
100	+	* java.util.concurrent.ConcurrentHashMap.  During transition, this
101	+	* class declares and uses nested functional interfaces with different
102	+	* names but the same forms as those expected for JDK8.<em>
103	+	*
104		* @since 1.5
105		* @author Doug Lea
106		* @param <K> the type of keys maintained by this map
107		* @param <V> the type of mapped values
108		*/
109	<	public class ConcurrentHashMap<K, V> extends AbstractMap<K, V>
110	<	implements ConcurrentMap<K, V>, Serializable {
109	>	public class ConcurrentHashMap<K, V>
110	>	implements ConcurrentMap<K, V>, Serializable {
111		private static final long serialVersionUID = 7249069246763182397L;
112
113	+	/**
114	+	* A partitionable iterator. A Spliterator can be traversed
115	+	* directly, but can also be partitioned (before traversal) by
116	+	* creating another Spliterator that covers a non-overlapping
117	+	* portion of the elements, and so may be amenable to parallel
118	+	* execution.
119	+	*
120	+	* <p> This interface exports a subset of expected JDK8
121	+	* functionality.
122	+	*
123	+	* <p>Sample usage: Here is one (of the several) ways to compute
124	+	* the sum of the values held in a map using the ForkJoin
125	+	* framework. As illustrated here, Spliterators are well suited to
126	+	* designs in which a task repeatedly splits off half its work
127	+	* into forked subtasks until small enough to process directly,
128	+	* and then joins these subtasks. Variants of this style can also
129	+	* be used in completion-based designs.
130	+	*
131	+	* <pre>
132	+	* {@code ConcurrentHashMap<String, Long> m = ...
133	+	* // split as if have 8 * parallelism, for load balance
134	+	* int n = m.size();
135	+	* int p = aForkJoinPool.getParallelism() * 8;
136	+	* int split = (n < p)? n : p;
137	+	* long sum = aForkJoinPool.invoke(new SumValues(m.valueSpliterator(), split, null));
138	+	* // ...
139	+	* static class SumValues extends RecursiveTask<Long> {
140	+	*   final Spliterator<Long> s;
141	+	*   final int split;             // split while > 1
142	+	*   final SumValues nextJoin;    // records forked subtasks to join
143	+	*   SumValues(Spliterator<Long> s, int depth, SumValues nextJoin) {
144	+	*     this.s = s; this.depth = depth; this.nextJoin = nextJoin;
145	+	*   }
146	+	*   public Long compute() {
147	+	*     long sum = 0;
148	+	*     SumValues subtasks = null; // fork subtasks
149	+	*     for (int s = split >>> 1; s > 0; s >>>= 1)
150	+	*       (subtasks = new SumValues(s.split(), s, subtasks)).fork();
151	+	*     while (s.hasNext())        // directly process remaining elements
152	+	*       sum += s.next();
153	+	*     for (SumValues t = subtasks; t != null; t = t.nextJoin)
154	+	*       sum += t.join();         // collect subtask results
155	+	*     return sum;
156	+	*   }
157	+	* }
158	+	* }</pre>
159	+	*/
160	+	public static interface Spliterator<T> extends Iterator<T> {
161	+	/**
162	+	* Returns a Spliterator covering approximately half of the
163	+	* elements, guaranteed not to overlap with those subsequently
164	+	* returned by this Spliterator.  After invoking this method,
165	+	* the current Spliterator will <em>not</em> produce any of
166	+	* the elements of the returned Spliterator, but the two
167	+	* Spliterators together will produce all of the elements that
168	+	* would have been produced by this Spliterator had this
169	+	* method not been called. The exact number of elements
170	+	* produced by the returned Spliterator is not guaranteed, and
171	+	* may be zero (i.e., with {@code hasNext()} reporting {@code
172	+	* false}) if this Spliterator cannot be further split.
173	+	*
174	+	* @return a Spliterator covering approximately half of the
175	+	* elements
176	+	* @throws IllegalStateException if this Spliterator has
177	+	* already commenced traversing elements
178	+	*/
179	+	Spliterator<T> split();
180	+	}
181	+
182		/*
183	<	* The basic strategy is to subdivide the table among Segments,
184	<	* each of which itself is a concurrently readable hash table.  To
185	<	* reduce footprint, all but one segments are constructed only
186	<	* when first needed (see ensureSegment). To maintain visibility
187	<	* in the presence of lazy construction, accesses to segments as
188	<	* well as elements of segment's table must use volatile access,
189	<	* which is done via Unsafe within methods segmentAt etc
190	<	* below. These provide the functionality of AtomicReferenceArrays
191	<	* but reduce the levels of indirection. Additionally,
192	<	* volatile-writes of table elements and entry "next" fields
193	<	* within locked operations use the cheaper "lazySet" forms of
194	<	* writes (via putOrderedObject) because these writes are always
195	<	* followed by lock releases that maintain sequential consistency
196	<	* of table updates.
197	<	*
198	<	* Historical note: The previous version of this class relied
199	<	* heavily on "final" fields, which avoided some volatile reads at
200	<	* the expense of a large initial footprint.  Some remnants of
201	<	* that design (including forced construction of segment 0) exist
202	<	* to ensure serialization compatibility.
183	>	* Overview:
184	>	*
185	>	* The primary design goal of this hash table is to maintain
186	>	* concurrent readability (typically method get(), but also
187	>	* iterators and related methods) while minimizing update
188	>	* contention. Secondary goals are to keep space consumption about
189	>	* the same or better than java.util.HashMap, and to support high
190	>	* initial insertion rates on an empty table by many threads.
191	>	*
192	>	* Each key-value mapping is held in a Node.  Because Node fields
193	>	* can contain special values, they are defined using plain Object
194	>	* types. Similarly in turn, all internal methods that use them
195	>	* work off Object types. And similarly, so do the internal
196	>	* methods of auxiliary iterator and view classes.  All public
197	>	* generic typed methods relay in/out of these internal methods,
198	>	* supplying null-checks and casts as needed. This also allows
199	>	* many of the public methods to be factored into a smaller number
200	>	* of internal methods (although sadly not so for the five
201	>	* variants of put-related operations). The validation-based
202	>	* approach explained below leads to a lot of code sprawl because
203	>	* retry-control precludes factoring into smaller methods.
204	>	*
205	>	* The table is lazily initialized to a power-of-two size upon the
206	>	* first insertion.  Each bin in the table normally contains a
207	>	* list of Nodes (most often, the list has only zero or one Node).
208	>	* Table accesses require volatile/atomic reads, writes, and
209	>	* CASes.  Because there is no other way to arrange this without
210	>	* adding further indirections, we use intrinsics
211	>	* (sun.misc.Unsafe) operations.  The lists of nodes within bins
212	>	* are always accurately traversable under volatile reads, so long
213	>	* as lookups check hash code and non-nullness of value before
214	>	* checking key equality.
215	>	*
216	>	* We use the top two bits of Node hash fields for control
217	>	* purposes -- they are available anyway because of addressing
218	>	* constraints.  As explained further below, these top bits are
219	>	* used as follows:
220	>	*  00 - Normal
221	>	*  01 - Locked
222	>	*  11 - Locked and may have a thread waiting for lock
223	>	*  10 - Node is a forwarding node
224	>	*
225	>	* The lower 30 bits of each Node's hash field contain a
226	>	* transformation of the key's hash code, except for forwarding
227	>	* nodes, for which the lower bits are zero (and so always have
228	>	* hash field == MOVED).
229	>	*
230	>	* Insertion (via put or its variants) of the first node in an
231	>	* empty bin is performed by just CASing it to the bin.  This is
232	>	* by far the most common case for put operations under most
233	>	* key/hash distributions.  Other update operations (insert,
234	>	* delete, and replace) require locks.  We do not want to waste
235	>	* the space required to associate a distinct lock object with
236	>	* each bin, so instead use the first node of a bin list itself as
237	>	* a lock. Blocking support for these locks relies on the builtin
238	>	* "synchronized" monitors.  However, we also need a tryLock
239	>	* construction, so we overlay these by using bits of the Node
240	>	* hash field for lock control (see above), and so normally use
241	>	* builtin monitors only for blocking and signalling using
242	>	* wait/notifyAll constructions. See Node.tryAwaitLock.
243	>	*
244	>	* Using the first node of a list as a lock does not by itself
245	>	* suffice though: When a node is locked, any update must first
246	>	* validate that it is still the first node after locking it, and
247	>	* retry if not. Because new nodes are always appended to lists,
248	>	* once a node is first in a bin, it remains first until deleted
249	>	* or the bin becomes invalidated (upon resizing).  However,
250	>	* operations that only conditionally update may inspect nodes
251	>	* until the point of update. This is a converse of sorts to the
252	>	* lazy locking technique described by Herlihy & Shavit.
253	>	*
254	>	* The main disadvantage of per-bin locks is that other update
255	>	* operations on other nodes in a bin list protected by the same
256	>	* lock can stall, for example when user equals() or mapping
257	>	* functions take a long time.  However, statistically, under
258	>	* random hash codes, this is not a common problem.  Ideally, the
259	>	* frequency of nodes in bins follows a Poisson distribution
260	>	* (http://en.wikipedia.org/wiki/Poisson_distribution) with a
261	>	* parameter of about 0.5 on average, given the resizing threshold
262	>	* of 0.75, although with a large variance because of resizing
263	>	* granularity. Ignoring variance, the expected occurrences of
264	>	* list size k are (exp(-0.5) * pow(0.5, k) / factorial(k)). The
265	>	* first values are:
266	>	*
267	>	* 0:    0.60653066
268	>	* 1:    0.30326533
269	>	* 2:    0.07581633
270	>	* 3:    0.01263606
271	>	* 4:    0.00157952
272	>	* 5:    0.00015795
273	>	* 6:    0.00001316
274	>	* 7:    0.00000094
275	>	* 8:    0.00000006
276	>	* more: less than 1 in ten million
277	>	*
278	>	* Lock contention probability for two threads accessing distinct
279	>	* elements is roughly 1 / (8 * #elements) under random hashes.
280	>	*
281	>	* Actual hash code distributions encountered in practice
282	>	* sometimes deviate significantly from uniform randomness.  This
283	>	* includes the case when N > (1<<30), so some keys MUST collide.
284	>	* Similarly for dumb or hostile usages in which multiple keys are
285	>	* designed to have identical hash codes. Also, although we guard
286	>	* against the worst effects of this (see method spread), sets of
287	>	* hashes may differ only in bits that do not impact their bin
288	>	* index for a given power-of-two mask.  So we use a secondary
289	>	* strategy that applies when the number of nodes in a bin exceeds
290	>	* a threshold, and at least one of the keys implements
291	>	* Comparable.  These TreeBins use a balanced tree to hold nodes
292	>	* (a specialized form of red-black trees), bounding search time
293	>	* to O(log N).  Each search step in a TreeBin is around twice as
294	>	* slow as in a regular list, but given that N cannot exceed
295	>	* (1<<64) (before running out of addresses) this bounds search
296	>	* steps, lock hold times, etc, to reasonable constants (roughly
297	>	* 100 nodes inspected per operation worst case) so long as keys
298	>	* are Comparable (which is very common -- String, Long, etc).
299	>	* TreeBin nodes (TreeNodes) also maintain the same "next"
300	>	* traversal pointers as regular nodes, so can be traversed in
301	>	* iterators in the same way.
302	>	*
303	>	* The table is resized when occupancy exceeds a percentage
304	>	* threshold (nominally, 0.75, but see below).  Only a single
305	>	* thread performs the resize (using field "sizeCtl", to arrange
306	>	* exclusion), but the table otherwise remains usable for reads
307	>	* and updates. Resizing proceeds by transferring bins, one by
308	>	* one, from the table to the next table.  Because we are using
309	>	* power-of-two expansion, the elements from each bin must either
310	>	* stay at same index, or move with a power of two offset. We
311	>	* eliminate unnecessary node creation by catching cases where old
312	>	* nodes can be reused because their next fields won't change.  On
313	>	* average, only about one-sixth of them need cloning when a table
314	>	* doubles. The nodes they replace will be garbage collectable as
315	>	* soon as they are no longer referenced by any reader thread that
316	>	* may be in the midst of concurrently traversing table.  Upon
317	>	* transfer, the old table bin contains only a special forwarding
318	>	* node (with hash field "MOVED") that contains the next table as
319	>	* its key. On encountering a forwarding node, access and update
320	>	* operations restart, using the new table.
321	>	*
322	>	* Each bin transfer requires its bin lock. However, unlike other
323	>	* cases, a transfer can skip a bin if it fails to acquire its
324	>	* lock, and revisit it later (unless it is a TreeBin). Method
325	>	* rebuild maintains a buffer of TRANSFER_BUFFER_SIZE bins that
326	>	* have been skipped because of failure to acquire a lock, and
327	>	* blocks only if none are available (i.e., only very rarely).
328	>	* The transfer operation must also ensure that all accessible
329	>	* bins in both the old and new table are usable by any traversal.
330	>	* When there are no lock acquisition failures, this is arranged
331	>	* simply by proceeding from the last bin (table.length - 1) up
332	>	* towards the first.  Upon seeing a forwarding node, traversals
333	>	* (see class Iter) arrange to move to the new table
334	>	* without revisiting nodes.  However, when any node is skipped
335	>	* during a transfer, all earlier table bins may have become
336	>	* visible, so are initialized with a reverse-forwarding node back
337	>	* to the old table until the new ones are established. (This
338	>	* sometimes requires transiently locking a forwarding node, which
339	>	* is possible under the above encoding.) These more expensive
340	>	* mechanics trigger only when necessary.
341	>	*
342	>	* The traversal scheme also applies to partial traversals of
343	>	* ranges of bins (via an alternate Traverser constructor)
344	>	* to support partitioned aggregate operations.  Also, read-only
345	>	* operations give up if ever forwarded to a null table, which
346	>	* provides support for shutdown-style clearing, which is also not
347	>	* currently implemented.
348	>	*
349	>	* Lazy table initialization minimizes footprint until first use,
350	>	* and also avoids resizings when the first operation is from a
351	>	* putAll, constructor with map argument, or deserialization.
352	>	* These cases attempt to override the initial capacity settings,
353	>	* but harmlessly fail to take effect in cases of races.
354	>	*
355	>	* The element count is maintained using a LongAdder, which avoids
356	>	* contention on updates but can encounter cache thrashing if read
357	>	* too frequently during concurrent access. To avoid reading so
358	>	* often, resizing is attempted either when a bin lock is
359	>	* contended, or upon adding to a bin already holding two or more
360	>	* nodes (checked before adding in the xIfAbsent methods, after
361	>	* adding in others). Under uniform hash distributions, the
362	>	* probability of this occurring at threshold is around 13%,
363	>	* meaning that only about 1 in 8 puts check threshold (and after
364	>	* resizing, many fewer do so). But this approximation has high
365	>	* variance for small table sizes, so we check on any collision
366	>	* for sizes <= 64. The bulk putAll operation further reduces
367	>	* contention by only committing count updates upon these size
368	>	* checks.
369	>	*
370	>	* Maintaining API and serialization compatibility with previous
371	>	* versions of this class introduces several oddities. Mainly: We
372	>	* leave untouched but unused constructor arguments refering to
373	>	* concurrencyLevel. We accept a loadFactor constructor argument,
374	>	* but apply it only to initial table capacity (which is the only
375	>	* time that we can guarantee to honor it.) We also declare an
376	>	* unused "Segment" class that is instantiated in minimal form
377	>	* only when serializing.
378		*/
379
380		/* ---------------- Constants -------------- */
381
382		/**
383	<	* The default initial capacity for this table,
384	<	* used when not otherwise specified in a constructor.
383	>	* The largest possible table capacity.  This value must be
384	>	* exactly 1<<30 to stay within Java array allocation and indexing
385	>	* bounds for power of two table sizes, and is further required
386	>	* because the top two bits of 32bit hash fields are used for
387	>	* control purposes.
388		*/
389	<	static final int DEFAULT_INITIAL_CAPACITY = 16;
389	>	private static final int MAXIMUM_CAPACITY = 1 << 30;
390
391		/**
392	<	* The default load factor for this table, used when not
393	<	* otherwise specified in a constructor.
392	>	* The default initial table capacity.  Must be a power of 2
393	>	* (i.e., at least 1) and at most MAXIMUM_CAPACITY.
394		*/
395	<	static final float DEFAULT_LOAD_FACTOR = 0.75f;
395	>	private static final int DEFAULT_CAPACITY = 16;
396
397		/**
398	<	* The default concurrency level for this table, used when not
399	<	* otherwise specified in a constructor.
398	>	* The largest possible (non-power of two) array size.
399	>	* Needed by toArray and related methods.
400		*/
401	<	static final int DEFAULT_CONCURRENCY_LEVEL = 16;
401	>	static final int MAX_ARRAY_SIZE = Integer.MAX_VALUE - 8;
402
403		/**
404	<	* The maximum capacity, used if a higher value is implicitly
405	<	* specified by either of the constructors with arguments.  MUST
123	<	* be a power of two <= 1<<30 to ensure that entries are indexable
124	<	* using ints.
404	>	* The default concurrency level for this table. Unused but
405	>	* defined for compatibility with previous versions of this class.
406		*/
407	<	static final int MAXIMUM_CAPACITY = 1 << 30;
407	>	private static final int DEFAULT_CONCURRENCY_LEVEL = 16;
408
409		/**
410	<	* The minimum capacity for per-segment tables.  Must be a power
411	<	* of two, at least two to avoid immediate resizing on next use
412	<	* after lazy construction.
410	>	* The load factor for this table. Overrides of this value in
411	>	* constructors affect only the initial table capacity.  The
412	>	* actual floating point value isn't normally used -- it is
413	>	* simpler to use expressions such as {@code n - (n >>> 2)} for
414	>	* the associated resizing threshold.
415		*/
416	<	static final int MIN_SEGMENT_TABLE_CAPACITY = 2;
416	>	private static final float LOAD_FACTOR = 0.75f;
417
418		/**
419	<	* The maximum number of segments to allow; used to bound
420	<	* constructor arguments. Must be power of two less than 1 << 24.
419	>	* The buffer size for skipped bins during transfers. The
420	>	* value is arbitrary but should be large enough to avoid
421	>	* most locking stalls during resizes.
422		*/
423	<	static final int MAX_SEGMENTS = 1 << 16; // slightly conservative
423	>	private static final int TRANSFER_BUFFER_SIZE = 32;
424
425		/**
426	<	* Number of unsynchronized retries in size and containsValue
427	<	* methods before resorting to locking. This is used to avoid
428	<	* unbounded retries if tables undergo continuous modification
145	<	* which would make it impossible to obtain an accurate result.
426	>	* The bin count threshold for using a tree rather than list for a
427	>	* bin.  The value reflects the approximate break-even point for
428	>	* using tree-based operations.
429		*/
430	<	static final int RETRIES_BEFORE_LOCK = 2;
430	>	private static final int TREE_THRESHOLD = 8;
431	>
432	>	/*
433	>	* Encodings for special uses of Node hash fields. See above for
434	>	* explanation.
435	>	*/
436	>	static final int MOVED     = 0x80000000; // hash field for forwarding nodes
437	>	static final int LOCKED    = 0x40000000; // set/tested only as a bit
438	>	static final int WAITING   = 0xc0000000; // both bits set/tested together
439	>	static final int HASH_BITS = 0x3fffffff; // usable bits of normal node hash
440
441		/* ---------------- Fields -------------- */
442
443		/**
444	<	* Mask value for indexing into segments. The upper bits of a
445	<	* key's hash code are used to choose the segment.
444	>	* The array of bins. Lazily initialized upon first insertion.
445	>	* Size is always a power of two. Accessed directly by iterators.
446		*/
447	<	final int segmentMask;
447	>	transient volatile Node[] table;
448
449		/**
450	<	* Shift value for indexing within segments.
450	>	* The counter maintaining number of elements.
451		*/
452	<	final int segmentShift;
452	>	private transient final LongAdder counter;
453
454		/**
455	<	* The segments, each of which is a specialized hash table.
455	>	* Table initialization and resizing control.  When negative, the
456	>	* table is being initialized or resized. Otherwise, when table is
457	>	* null, holds the initial table size to use upon creation, or 0
458	>	* for default. After initialization, holds the next element count
459	>	* value upon which to resize the table.
460		*/
461	<	final Segment<K,V>[] segments;
461	>	private transient volatile int sizeCtl;
462	>
463	>	// views
464	>	private transient KeySet<K,V> keySet;
465	>	private transient Values<K,V> values;
466	>	private transient EntrySet<K,V> entrySet;
467
468	<	transient Set<K> keySet;
469	<	transient Set<Map.Entry<K,V>> entrySet;
470	<	transient Collection<V> values;
468	>	/** For serialization compatibility. Null unless serialized; see below */
469	>	private Segment<K,V>[] segments;
470	>
471	>	/* ---------------- Table element access -------------- */
472	>
473	>	/*
474	>	* Volatile access methods are used for table elements as well as
475	>	* elements of in-progress next table while resizing.  Uses are
476	>	* null checked by callers, and implicitly bounds-checked, relying
477	>	* on the invariants that tab arrays have non-zero size, and all
478	>	* indices are masked with (tab.length - 1) which is never
479	>	* negative and always less than length. Note that, to be correct
480	>	* wrt arbitrary concurrency errors by users, bounds checks must
481	>	* operate on local variables, which accounts for some odd-looking
482	>	* inline assignments below.
483	>	*/
484	>
485	>	static final Node tabAt(Node[] tab, int i) { // used by Iter
486	>	return (Node)UNSAFE.getObjectVolatile(tab, ((long)i<<ASHIFT)+ABASE);
487	>	}
488	>
489	>	private static final boolean casTabAt(Node[] tab, int i, Node c, Node v) {
490	>	return UNSAFE.compareAndSwapObject(tab, ((long)i<<ASHIFT)+ABASE, c, v);
491	>	}
492	>
493	>	private static final void setTabAt(Node[] tab, int i, Node v) {
494	>	UNSAFE.putObjectVolatile(tab, ((long)i<<ASHIFT)+ABASE, v);
495	>	}
496	>
497	>	/* ---------------- Nodes -------------- */
498
499		/**
500	<	* ConcurrentHashMap list entry. Note that this is never exported
501	<	* out as a user-visible Map.Entry.
500	>	* Key-value entry. Note that this is never exported out as a
501	>	* user-visible Map.Entry (see MapEntry below). Nodes with a hash
502	>	* field of MOVED are special, and do not contain user keys or
503	>	* values.  Otherwise, keys are never null, and null val fields
504	>	* indicate that a node is in the process of being deleted or
505	>	* created. For purposes of read-only access, a key may be read
506	>	* before a val, but can only be used after checking val to be
507	>	* non-null.
508		*/
509	<	static final class HashEntry<K,V> {
510	<	final int hash;
511	<	final K key;
512	<	volatile V value;
513	<	volatile HashEntry<K,V> next;
509	>	static class Node {
510	>	volatile int hash;
511	>	final Object key;
512	>	volatile Object val;
513	>	volatile Node next;
514
515	<	HashEntry(int hash, K key, V value, HashEntry<K,V> next) {
515	>	Node(int hash, Object key, Object val, Node next) {
516		this.hash = hash;
517		this.key = key;
518	<	this.value = value;
518	>	this.val = val;
519		this.next = next;
520		}
521
522	+	/** CompareAndSet the hash field */
523	+	final boolean casHash(int cmp, int val) {
524	+	return UNSAFE.compareAndSwapInt(this, hashOffset, cmp, val);
525	+	}
526	+
527	+	/** The number of spins before blocking for a lock */
528	+	static final int MAX_SPINS =
529	+	Runtime.getRuntime().availableProcessors() > 1 ? 64 : 1;
530	+
531		/**
532	<	* Sets next field with volatile write semantics.  (See above
533	<	* about use of putOrderedObject.)
532	>	* Spins a while if LOCKED bit set and this node is the first
533	>	* of its bin, and then sets WAITING bits on hash field and
534	>	* blocks (once) if they are still set.  It is OK for this
535	>	* method to return even if lock is not available upon exit,
536	>	* which enables these simple single-wait mechanics.
537	>	*
538	>	* The corresponding signalling operation is performed within
539	>	* callers: Upon detecting that WAITING has been set when
540	>	* unlocking lock (via a failed CAS from non-waiting LOCKED
541	>	* state), unlockers acquire the sync lock and perform a
542	>	* notifyAll.
543		*/
544	<	final void setNext(HashEntry<K,V> n) {
545	<	UNSAFE.putOrderedObject(this, nextOffset, n);
544	>	final void tryAwaitLock(Node[] tab, int i) {
545	>	if (tab != null && i >= 0 && i < tab.length) { // bounds check
546	>	int r = ThreadLocalRandom.current().nextInt(); // randomize spins
547	>	int spins = MAX_SPINS, h;
548	>	while (tabAt(tab, i) == this && ((h = hash) & LOCKED) != 0) {
549	>	if (spins >= 0) {
550	>	r ^= r << 1; r ^= r >>> 3; r ^= r << 10; // xorshift
551	>	if (r >= 0 && --spins == 0)
552	>	Thread.yield();  // yield before block
553	>	}
554	>	else if (casHash(h, h | WAITING)) {
555	>	synchronized (this) {
556	>	if (tabAt(tab, i) == this &&
557	>	(hash & WAITING) == WAITING) {
558	>	try {
559	>	wait();
560	>	} catch (InterruptedException ie) {
561	>	Thread.currentThread().interrupt();
562	>	}
563	>	}
564	>	else
565	>	notifyAll(); // possibly won race vs signaller
566	>	}
567	>	break;
568	>	}
569	>	}
570	>	}
571		}
572
573	<	// Unsafe mechanics
574	<	static final sun.misc.Unsafe UNSAFE;
575	<	static final long nextOffset;
573	>	// Unsafe mechanics for casHash
574	>	private static final sun.misc.Unsafe UNSAFE;
575	>	private static final long hashOffset;
576	>
577		static {
578		try {
579		UNSAFE = sun.misc.Unsafe.getUnsafe();
580	<	Class<?> k = HashEntry.class;
581	<	nextOffset = UNSAFE.objectFieldOffset
582	<	(k.getDeclaredField("next"));
580	>	Class<?> k = Node.class;
581	>	hashOffset = UNSAFE.objectFieldOffset
582	>	(k.getDeclaredField("hash"));
583		} catch (Exception e) {
584		throw new Error(e);
585		}
586		}
587		}
588
589	+	/* ---------------- TreeBins -------------- */
590	+
591		/**
592	<	* Gets the ith element of given table (if nonnull) with volatile
213	<	* read semantics. Note: This is manually integrated into a few
214	<	* performance-sensitive methods to reduce call overhead.
592	>	* Nodes for use in TreeBins
593		*/
594	<	@SuppressWarnings("unchecked")
595	<	static final <K,V> HashEntry<K,V> entryAt(HashEntry<K,V>[] tab, int i) {
596	<	return (tab == null) ? null :
597	<	(HashEntry<K,V>) UNSAFE.getObjectVolatile
598	<	(tab, ((long)i << TSHIFT) + TBASE);
599	<	}
594	>	static final class TreeNode extends Node {
595	>	TreeNode parent;  // red-black tree links
596	>	TreeNode left;
597	>	TreeNode right;
598	>	TreeNode prev;    // needed to unlink next upon deletion
599	>	boolean red;
600
601	<	/**
602	<	* Sets the ith element of given table, with volatile write
603	<	* semantics. (See above about use of putOrderedObject.)
604	<	*/
227	<	static final <K,V> void setEntryAt(HashEntry<K,V>[] tab, int i,
228	<	HashEntry<K,V> e) {
229	<	UNSAFE.putOrderedObject(tab, ((long)i << TSHIFT) + TBASE, e);
601	>	TreeNode(int hash, Object key, Object val, Node next, TreeNode parent) {
602	>	super(hash, key, val, next);
603	>	this.parent = parent;
604	>	}
605		}
606
607		/**
608	<	* Applies a supplemental hash function to a given hashCode, which
609	<	* defends against poor quality hash functions.  This is critical
610	<	* because ConcurrentHashMap uses power-of-two length hash tables,
611	<	* that otherwise encounter collisions for hashCodes that do not
612	<	* differ in lower or upper bits.
613	<	*/
614	<	private static int hash(int h) {
615	<	// Spread bits to regularize both segment and index locations,
616	<	// using variant of single-word Wang/Jenkins hash.
617	<	h += (h <<  15) ^ 0xffffcd7d;
618	<	h ^= (h >>> 10);
619	<	h += (h <<   3);
620	<	h ^= (h >>>  6);
621	<	h += (h <<   2) + (h << 14);
622	<	return h ^ (h >>> 16);
623	<	}
608	>	* A specialized form of red-black tree for use in bins
609	>	* whose size exceeds a threshold.
610	>	*
611	>	* TreeBins use a special form of comparison for search and
612	>	* related operations (which is the main reason we cannot use
613	>	* existing collections such as TreeMaps). TreeBins contain
614	>	* Comparable elements, but may contain others, as well as
615	>	* elements that are Comparable but not necessarily Comparable<T>
616	>	* for the same T, so we cannot invoke compareTo among them. To
617	>	* handle this, the tree is ordered primarily by hash value, then
618	>	* by getClass().getName() order, and then by Comparator order
619	>	* among elements of the same class.  On lookup at a node, if
620	>	* elements are not comparable or compare as 0, both left and
621	>	* right children may need to be searched in the case of tied hash
622	>	* values. (This corresponds to the full list search that would be
623	>	* necessary if all elements were non-Comparable and had tied
624	>	* hashes.)  The red-black balancing code is updated from
625	>	* pre-jdk-collections
626	>	* (http://gee.cs.oswego.edu/dl/classes/collections/RBCell.java)
627	>	* based in turn on Cormen, Leiserson, and Rivest "Introduction to
628	>	* Algorithms" (CLR).
629	>	*
630	>	* TreeBins also maintain a separate locking discipline than
631	>	* regular bins. Because they are forwarded via special MOVED
632	>	* nodes at bin heads (which can never change once established),
633	>	* we cannot use those nodes as locks. Instead, TreeBin
634	>	* extends AbstractQueuedSynchronizer to support a simple form of
635	>	* read-write lock. For update operations and table validation,
636	>	* the exclusive form of lock behaves in the same way as bin-head
637	>	* locks. However, lookups use shared read-lock mechanics to allow
638	>	* multiple readers in the absence of writers.  Additionally,
639	>	* these lookups do not ever block: While the lock is not
640	>	* available, they proceed along the slow traversal path (via
641	>	* next-pointers) until the lock becomes available or the list is
642	>	* exhausted, whichever comes first. (These cases are not fast,
643	>	* but maximize aggregate expected throughput.)  The AQS mechanics
644	>	* for doing this are straightforward.  The lock state is held as
645	>	* AQS getState().  Read counts are negative; the write count (1)
646	>	* is positive.  There are no signalling preferences among readers
647	>	* and writers. Since we don't need to export full Lock API, we
648	>	* just override the minimal AQS methods and use them directly.
649	>	*/
650	>	static final class TreeBin extends AbstractQueuedSynchronizer {
651	>	private static final long serialVersionUID = 2249069246763182397L;
652	>	transient TreeNode root;  // root of tree
653	>	transient TreeNode first; // head of next-pointer list
654
655	<	/**
656	<	* Segments are specialized versions of hash tables.  This
657	<	* subclasses from ReentrantLock opportunistically, just to
658	<	* simplify some locking and avoid separate construction.
659	<	*/
660	<	static final class Segment<K,V> extends ReentrantLock implements Serializable {
661	<	/*
662	<	* Segments maintain a table of entry lists that are always
663	<	* kept in a consistent state, so can be read (via volatile
664	<	* reads of segments and tables) without locking.  This
665	<	* requires replicating nodes when necessary during table
666	<	* resizing, so the old lists can be traversed by readers
667	<	* still using old version of table.
668	<	*
669	<	* This class defines only mutative methods requiring locking.
670	<	* Except as noted, the methods of this class perform the
671	<	* per-segment versions of ConcurrentHashMap methods.  (Other
672	<	* methods are integrated directly into ConcurrentHashMap
673	<	* methods.) These mutative methods use a form of controlled
674	<	* spinning on contention via methods scanAndLock and
675	<	* scanAndLockForPut. These intersperse tryLocks with
676	<	* traversals to locate nodes.  The main benefit is to absorb
677	<	* cache misses (which are very common for hash tables) while
678	<	* obtaining locks so that traversal is faster once
679	<	* acquired. We do not actually use the found nodes since they
680	<	* must be re-acquired under lock anyway to ensure sequential
681	<	* consistency of updates (and in any case may be undetectably
682	<	* stale), but they will normally be much faster to re-locate.
683	<	* Also, scanAndLockForPut speculatively creates a fresh node
684	<	* to use in put if no node is found.
685	<	*/
655	>	/* AQS overrides */
656	>	public final boolean isHeldExclusively() { return getState() > 0; }
657	>	public final boolean tryAcquire(int ignore) {
658	>	if (compareAndSetState(0, 1)) {
659	>	setExclusiveOwnerThread(Thread.currentThread());
660	>	return true;
661	>	}
662	>	return false;
663	>	}
664	>	public final boolean tryRelease(int ignore) {
665	>	setExclusiveOwnerThread(null);
666	>	setState(0);
667	>	return true;
668	>	}
669	>	public final int tryAcquireShared(int ignore) {
670	>	for (int c;;) {
671	>	if ((c = getState()) > 0)
672	>	return -1;
673	>	if (compareAndSetState(c, c -1))
674	>	return 1;
675	>	}
676	>	}
677	>	public final boolean tryReleaseShared(int ignore) {
678	>	int c;
679	>	do {} while (!compareAndSetState(c = getState(), c + 1));
680	>	return c == -1;
681	>	}
682	>
683	>	/** From CLR */
684	>	private void rotateLeft(TreeNode p) {
685	>	if (p != null) {
686	>	TreeNode r = p.right, pp, rl;
687	>	if ((rl = p.right = r.left) != null)
688	>	rl.parent = p;
689	>	if ((pp = r.parent = p.parent) == null)
690	>	root = r;
691	>	else if (pp.left == p)
692	>	pp.left = r;
693	>	else
694	>	pp.right = r;
695	>	r.left = p;
696	>	p.parent = r;
697	>	}
698	>	}
699
700	<	private static final long serialVersionUID = 2249069246763182397L;
700	>	/** From CLR */
701	>	private void rotateRight(TreeNode p) {
702	>	if (p != null) {
703	>	TreeNode l = p.left, pp, lr;
704	>	if ((lr = p.left = l.right) != null)
705	>	lr.parent = p;
706	>	if ((pp = l.parent = p.parent) == null)
707	>	root = l;
708	>	else if (pp.right == p)
709	>	pp.right = l;
710	>	else
711	>	pp.left = l;
712	>	l.right = p;
713	>	p.parent = l;
714	>	}
715	>	}
716
717		/**
718	<	* The maximum number of times to tryLock in a prescan before
719	<	* possibly blocking on acquire in preparation for a locked
287	<	* segment operation. On multiprocessors, using a bounded
288	<	* number of retries maintains cache acquired while locating
289	<	* nodes.
718	>	* Returns the TreeNode (or null if not found) for the given key
719	>	* starting at given root.
720		*/
721	<	static final int MAX_SCAN_RETRIES =
722	<	Runtime.getRuntime().availableProcessors() > 1 ? 64 : 1;
721	>	@SuppressWarnings("unchecked") // suppress Comparable cast warning
722	>	final TreeNode getTreeNode(int h, Object k, TreeNode p) {
723	>	Class<?> c = k.getClass();
724	>	while (p != null) {
725	>	int dir, ph;  Object pk; Class<?> pc;
726	>	if ((ph = p.hash) == h) {
727	>	if ((pk = p.key) == k || k.equals(pk))
728	>	return p;
729	>	if (c != (pc = pk.getClass()) ||
730	>	!(k instanceof Comparable) ||
731	>	(dir = ((Comparable)k).compareTo((Comparable)pk)) == 0) {
732	>	dir = (c == pc) ? 0 : c.getName().compareTo(pc.getName());
733	>	TreeNode r = null, s = null, pl, pr;
734	>	if (dir >= 0) {
735	>	if ((pl = p.left) != null && h <= pl.hash)
736	>	s = pl;
737	>	}
738	>	else if ((pr = p.right) != null && h >= pr.hash)
739	>	s = pr;
740	>	if (s != null && (r = getTreeNode(h, k, s)) != null)
741	>	return r;
742	>	}
743	>	}
744	>	else
745	>	dir = (h < ph) ? -1 : 1;
746	>	p = (dir > 0) ? p.right : p.left;
747	>	}
748	>	return null;
749	>	}
750
751		/**
752	<	* The per-segment table. Elements are accessed via
753	<	* entryAt/setEntryAt providing volatile semantics.
752	>	* Wrapper for getTreeNode used by CHM.get. Tries to obtain
753	>	* read-lock to call getTreeNode, but during failure to get
754	>	* lock, searches along next links.
755		*/
756	<	transient volatile HashEntry<K,V>[] table;
756	>	final Object getValue(int h, Object k) {
757	>	Node r = null;
758	>	int c = getState(); // Must read lock state first
759	>	for (Node e = first; e != null; e = e.next) {
760	>	if (c <= 0 && compareAndSetState(c, c - 1)) {
761	>	try {
762	>	r = getTreeNode(h, k, root);
763	>	} finally {
764	>	releaseShared(0);
765	>	}
766	>	break;
767	>	}
768	>	else if ((e.hash & HASH_BITS) == h && k.equals(e.key)) {
769	>	r = e;
770	>	break;
771	>	}
772	>	else
773	>	c = getState();
774	>	}
775	>	return r == null ? null : r.val;
776	>	}
777
778		/**
779	<	* The number of elements. Accessed only either within locks
780	<	* or among other volatile reads that maintain visibility.
779	>	* Finds or adds a node.
780	>	* @return null if added
781		*/
782	<	transient int count;
782	>	@SuppressWarnings("unchecked") // suppress Comparable cast warning
783	>	final TreeNode putTreeNode(int h, Object k, Object v) {
784	>	Class<?> c = k.getClass();
785	>	TreeNode pp = root, p = null;
786	>	int dir = 0;
787	>	while (pp != null) { // find existing node or leaf to insert at
788	>	int ph;  Object pk; Class<?> pc;
789	>	p = pp;
790	>	if ((ph = p.hash) == h) {
791	>	if ((pk = p.key) == k || k.equals(pk))
792	>	return p;
793	>	if (c != (pc = pk.getClass()) ||
794	>	!(k instanceof Comparable) ||
795	>	(dir = ((Comparable)k).compareTo((Comparable)pk)) == 0) {
796	>	dir = (c == pc) ? 0 : c.getName().compareTo(pc.getName());
797	>	TreeNode r = null, s = null, pl, pr;
798	>	if (dir >= 0) {
799	>	if ((pl = p.left) != null && h <= pl.hash)
800	>	s = pl;
801	>	}
802	>	else if ((pr = p.right) != null && h >= pr.hash)
803	>	s = pr;
804	>	if (s != null && (r = getTreeNode(h, k, s)) != null)
805	>	return r;
806	>	}
807	>	}
808	>	else
809	>	dir = (h < ph) ? -1 : 1;
810	>	pp = (dir > 0) ? p.right : p.left;
811	>	}
812
813	<	/**
814	<	* The total number of mutative operations in this segment.
815	<	* Even though this may overflows 32 bits, it provides
816	<	* sufficient accuracy for stability checks in CHM isEmpty()
817	<	* and size() methods.  Accessed only either within locks or
818	<	* among other volatile reads that maintain visibility.
819	<	*/
820	<	transient int modCount;
813	>	TreeNode f = first;
814	>	TreeNode x = first = new TreeNode(h, k, v, f, p);
815	>	if (p == null)
816	>	root = x;
817	>	else { // attach and rebalance; adapted from CLR
818	>	TreeNode xp, xpp;
819	>	if (f != null)
820	>	f.prev = x;
821	>	if (dir <= 0)
822	>	p.left = x;
823	>	else
824	>	p.right = x;
825	>	x.red = true;
826	>	while (x != null && (xp = x.parent) != null && xp.red &&
827	>	(xpp = xp.parent) != null) {
828	>	TreeNode xppl = xpp.left;
829	>	if (xp == xppl) {
830	>	TreeNode y = xpp.right;
831	>	if (y != null && y.red) {
832	>	y.red = false;
833	>	xp.red = false;
834	>	xpp.red = true;
835	>	x = xpp;
836	>	}
837	>	else {
838	>	if (x == xp.right) {
839	>	rotateLeft(x = xp);
840	>	xpp = (xp = x.parent) == null ? null : xp.parent;
841	>	}
842	>	if (xp != null) {
843	>	xp.red = false;
844	>	if (xpp != null) {
845	>	xpp.red = true;
846	>	rotateRight(xpp);
847	>	}
848	>	}
849	>	}
850	>	}
851	>	else {
852	>	TreeNode y = xppl;
853	>	if (y != null && y.red) {
854	>	y.red = false;
855	>	xp.red = false;
856	>	xpp.red = true;
857	>	x = xpp;
858	>	}
859	>	else {
860	>	if (x == xp.left) {
861	>	rotateRight(x = xp);
862	>	xpp = (xp = x.parent) == null ? null : xp.parent;
863	>	}
864	>	if (xp != null) {
865	>	xp.red = false;
866	>	if (xpp != null) {
867	>	xpp.red = true;
868	>	rotateLeft(xpp);
869	>	}
870	>	}
871	>	}
872	>	}
873	>	}
874	>	TreeNode r = root;
875	>	if (r != null && r.red)
876	>	r.red = false;
877	>	}
878	>	return null;
879	>	}
880
881		/**
882	<	* The table is rehashed when its size exceeds this threshold.
883	<	* (The value of this field is always <tt>(int)(capacity *
884	<	* loadFactor)</tt>.)
882	>	* Removes the given node, that must be present before this
883	>	* call.  This is messier than typical red-black deletion code
884	>	* because we cannot swap the contents of an interior node
885	>	* with a leaf successor that is pinned by "next" pointers
886	>	* that are accessible independently of lock. So instead we
887	>	* swap the tree linkages.
888		*/
889	<	transient int threshold;
889	>	final void deleteTreeNode(TreeNode p) {
890	>	TreeNode next = (TreeNode)p.next; // unlink traversal pointers
891	>	TreeNode pred = p.prev;
892	>	if (pred == null)
893	>	first = next;
894	>	else
895	>	pred.next = next;
896	>	if (next != null)
897	>	next.prev = pred;
898	>	TreeNode replacement;
899	>	TreeNode pl = p.left;
900	>	TreeNode pr = p.right;
901	>	if (pl != null && pr != null) {
902	>	TreeNode s = pr, sl;
903	>	while ((sl = s.left) != null) // find successor
904	>	s = sl;
905	>	boolean c = s.red; s.red = p.red; p.red = c; // swap colors
906	>	TreeNode sr = s.right;
907	>	TreeNode pp = p.parent;
908	>	if (s == pr) { // p was s's direct parent
909	>	p.parent = s;
910	>	s.right = p;
911	>	}
912	>	else {
913	>	TreeNode sp = s.parent;
914	>	if ((p.parent = sp) != null) {
915	>	if (s == sp.left)
916	>	sp.left = p;
917	>	else
918	>	sp.right = p;
919	>	}
920	>	if ((s.right = pr) != null)
921	>	pr.parent = s;
922	>	}
923	>	p.left = null;
924	>	if ((p.right = sr) != null)
925	>	sr.parent = p;
926	>	if ((s.left = pl) != null)
927	>	pl.parent = s;
928	>	if ((s.parent = pp) == null)
929	>	root = s;
930	>	else if (p == pp.left)
931	>	pp.left = s;
932	>	else
933	>	pp.right = s;
934	>	replacement = sr;
935	>	}
936	>	else
937	>	replacement = (pl != null) ? pl : pr;
938	>	TreeNode pp = p.parent;
939	>	if (replacement == null) {
940	>	if (pp == null) {
941	>	root = null;
942	>	return;
943	>	}
944	>	replacement = p;
945	>	}
946	>	else {
947	>	replacement.parent = pp;
948	>	if (pp == null)
949	>	root = replacement;
950	>	else if (p == pp.left)
951	>	pp.left = replacement;
952	>	else
953	>	pp.right = replacement;
954	>	p.left = p.right = p.parent = null;
955	>	}
956	>	if (!p.red) { // rebalance, from CLR
957	>	TreeNode x = replacement;
958	>	while (x != null) {
959	>	TreeNode xp, xpl;
960	>	if (x.red || (xp = x.parent) == null) {
961	>	x.red = false;
962	>	break;
963	>	}
964	>	if (x == (xpl = xp.left)) {
965	>	TreeNode sib = xp.right;
966	>	if (sib != null && sib.red) {
967	>	sib.red = false;
968	>	xp.red = true;
969	>	rotateLeft(xp);
970	>	sib = (xp = x.parent) == null ? null : xp.right;
971	>	}
972	>	if (sib == null)
973	>	x = xp;
974	>	else {
975	>	TreeNode sl = sib.left, sr = sib.right;
976	>	if ((sr == null || !sr.red) &&
977	>	(sl == null || !sl.red)) {
978	>	sib.red = true;
979	>	x = xp;
980	>	}
981	>	else {
982	>	if (sr == null || !sr.red) {
983	>	if (sl != null)
984	>	sl.red = false;
985	>	sib.red = true;
986	>	rotateRight(sib);
987	>	sib = (xp = x.parent) == null ? null : xp.right;
988	>	}
989	>	if (sib != null) {
990	>	sib.red = (xp == null) ? false : xp.red;
991	>	if ((sr = sib.right) != null)
992	>	sr.red = false;
993	>	}
994	>	if (xp != null) {
995	>	xp.red = false;
996	>	rotateLeft(xp);
997	>	}
998	>	x = root;
999	>	}
1000	>	}
1001	>	}
1002	>	else { // symmetric
1003	>	TreeNode sib = xpl;
1004	>	if (sib != null && sib.red) {
1005	>	sib.red = false;
1006	>	xp.red = true;
1007	>	rotateRight(xp);
1008	>	sib = (xp = x.parent) == null ? null : xp.left;
1009	>	}
1010	>	if (sib == null)
1011	>	x = xp;
1012	>	else {
1013	>	TreeNode sl = sib.left, sr = sib.right;
1014	>	if ((sl == null || !sl.red) &&
1015	>	(sr == null || !sr.red)) {
1016	>	sib.red = true;
1017	>	x = xp;
1018	>	}
1019	>	else {
1020	>	if (sl == null || !sl.red) {
1021	>	if (sr != null)
1022	>	sr.red = false;
1023	>	sib.red = true;
1024	>	rotateLeft(sib);
1025	>	sib = (xp = x.parent) == null ? null : xp.left;
1026	>	}
1027	>	if (sib != null) {
1028	>	sib.red = (xp == null) ? false : xp.red;
1029	>	if ((sl = sib.left) != null)
1030	>	sl.red = false;
1031	>	}
1032	>	if (xp != null) {
1033	>	xp.red = false;
1034	>	rotateRight(xp);
1035	>	}
1036	>	x = root;
1037	>	}
1038	>	}
1039	>	}
1040	>	}
1041	>	}
1042	>	if (p == replacement && (pp = p.parent) != null) {
1043	>	if (p == pp.left) // detach pointers
1044	>	pp.left = null;
1045	>	else if (p == pp.right)
1046	>	pp.right = null;
1047	>	p.parent = null;
1048	>	}
1049	>	}
1050	>	}
1051
1052	<	/**
323	<	* The load factor for the hash table.  Even though this value
324	<	* is same for all segments, it is replicated to avoid needing
325	<	* links to outer object.
326	<	* @serial
327	<	*/
328	<	final float loadFactor;
1052	>	/* ---------------- Collision reduction methods -------------- */
1053
1054	<	Segment(float lf, int threshold, HashEntry<K,V>[] tab) {
1055	<	this.loadFactor = lf;
1056	<	this.threshold = threshold;
1057	<	this.table = tab;
1054	>	/**
1055	>	* Spreads higher bits to lower, and also forces top 2 bits to 0.
1056	>	* Because the table uses power-of-two masking, sets of hashes
1057	>	* that vary only in bits above the current mask will always
1058	>	* collide. (Among known examples are sets of Float keys holding
1059	>	* consecutive whole numbers in small tables.)  To counter this,
1060	>	* we apply a transform that spreads the impact of higher bits
1061	>	* downward. There is a tradeoff between speed, utility, and
1062	>	* quality of bit-spreading. Because many common sets of hashes
1063	>	* are already reasonably distributed across bits (so don't benefit
1064	>	* from spreading), and because we use trees to handle large sets
1065	>	* of collisions in bins, we don't need excessively high quality.
1066	>	*/
1067	>	private static final int spread(int h) {
1068	>	h ^= (h >>> 18) ^ (h >>> 12);
1069	>	return (h ^ (h >>> 10)) & HASH_BITS;
1070	>	}
1071	>
1072	>	/**
1073	>	* Replaces a list bin with a tree bin. Call only when locked.
1074	>	* Fails to replace if the given key is non-comparable or table
1075	>	* is, or needs, resizing.
1076	>	*/
1077	>	private final void replaceWithTreeBin(Node[] tab, int index, Object key) {
1078	>	if ((key instanceof Comparable) &&
1079	>	(tab.length >= MAXIMUM_CAPACITY || counter.sum() < (long)sizeCtl)) {
1080	>	TreeBin t = new TreeBin();
1081	>	for (Node e = tabAt(tab, index); e != null; e = e.next)
1082	>	t.putTreeNode(e.hash & HASH_BITS, e.key, e.val);
1083	>	setTabAt(tab, index, new Node(MOVED, t, null, null));
1084		}
1085	+	}
1086
1087	<	final V put(K key, int hash, V value, boolean onlyIfAbsent) {
1088	<	HashEntry<K,V> node = tryLock() ? null :
1089	<	scanAndLockForPut(key, hash, value);
1090	<	V oldValue;
1091	<	try {
1092	<	HashEntry<K,V>[] tab = table;
1093	<	int index = (tab.length - 1) & hash;
1094	<	HashEntry<K,V> first = entryAt(tab, index);
1095	<	for (HashEntry<K,V> e = first;;) {
1096	<	if (e != null) {
1097	<	K k;
1098	<	if ((k = e.key) == key ||
1099	<	(e.hash == hash && key.equals(k))) {
1100	<	oldValue = e.value;
1101	<	if (!onlyIfAbsent) {
1102	<	e.value = value;
1103	<	++modCount;
1087	>	/* ---------------- Internal access and update methods -------------- */
1088	>
1089	>	/** Implementation for get and containsKey */
1090	>	private final Object internalGet(Object k) {
1091	>	int h = spread(k.hashCode());
1092	>	retry: for (Node[] tab = table; tab != null;) {
1093	>	Node e, p; Object ek, ev; int eh;      // locals to read fields once
1094	>	for (e = tabAt(tab, (tab.length - 1) & h); e != null; e = e.next) {
1095	>	if ((eh = e.hash) == MOVED) {
1096	>	if ((ek = e.key) instanceof TreeBin)  // search TreeBin
1097	>	return ((TreeBin)ek).getValue(h, k);
1098	>	else {                        // restart with new table
1099	>	tab = (Node[])ek;
1100	>	continue retry;
1101	>	}
1102	>	}
1103	>	else if ((eh & HASH_BITS) == h && (ev = e.val) != null &&
1104	>	((ek = e.key) == k || k.equals(ek)))
1105	>	return ev;
1106	>	}
1107	>	break;
1108	>	}
1109	>	return null;
1110	>	}
1111	>
1112	>	/**
1113	>	* Implementation for the four public remove/replace methods:
1114	>	* Replaces node value with v, conditional upon match of cv if
1115	>	* non-null.  If resulting value is null, delete.
1116	>	*/
1117	>	private final Object internalReplace(Object k, Object v, Object cv) {
1118	>	int h = spread(k.hashCode());
1119	>	Object oldVal = null;
1120	>	for (Node[] tab = table;;) {
1121	>	Node f; int i, fh; Object fk;
1122	>	if (tab == null ||
1123	>	(f = tabAt(tab, i = (tab.length - 1) & h)) == null)
1124	>	break;
1125	>	else if ((fh = f.hash) == MOVED) {
1126	>	if ((fk = f.key) instanceof TreeBin) {
1127	>	TreeBin t = (TreeBin)fk;
1128	>	boolean validated = false;
1129	>	boolean deleted = false;
1130	>	t.acquire(0);
1131	>	try {
1132	>	if (tabAt(tab, i) == f) {
1133	>	validated = true;
1134	>	TreeNode p = t.getTreeNode(h, k, t.root);
1135	>	if (p != null) {
1136	>	Object pv = p.val;
1137	>	if (cv == null || cv == pv || cv.equals(pv)) {
1138	>	oldVal = pv;
1139	>	if ((p.val = v) == null) {
1140	>	deleted = true;
1141	>	t.deleteTreeNode(p);
1142	>	}
1143	>	}
1144		}
354	–	break;
1145		}
1146	<	e = e.next;
1146	>	} finally {
1147	>	t.release(0);
1148		}
1149	<	else {
1150	<	if (node != null)
1151	<	node.setNext(first);
361	<	else
362	<	node = new HashEntry<K,V>(hash, key, value, first);
363	<	int c = count + 1;
364	<	if (c > threshold && tab.length < MAXIMUM_CAPACITY)
365	<	rehash(node);
366	<	else
367	<	setEntryAt(tab, index, node);
368	<	++modCount;
369	<	count = c;
370	<	oldValue = null;
1149	>	if (validated) {
1150	>	if (deleted)
1151	>	counter.add(-1L);
1152		break;
1153		}
1154		}
1155	<	} finally {
1156	<	unlock();
1155	>	else
1156	>	tab = (Node[])fk;
1157	>	}
1158	>	else if ((fh & HASH_BITS) != h && f.next == null) // precheck
1159	>	break;                          // rules out possible existence
1160	>	else if ((fh & LOCKED) != 0) {
1161	>	checkForResize();               // try resizing if can't get lock
1162	>	f.tryAwaitLock(tab, i);
1163	>	}
1164	>	else if (f.casHash(fh, fh | LOCKED)) {
1165	>	boolean validated = false;
1166	>	boolean deleted = false;
1167	>	try {
1168	>	if (tabAt(tab, i) == f) {
1169	>	validated = true;
1170	>	for (Node e = f, pred = null;;) {
1171	>	Object ek, ev;
1172	>	if ((e.hash & HASH_BITS) == h &&
1173	>	((ev = e.val) != null) &&
1174	>	((ek = e.key) == k || k.equals(ek))) {
1175	>	if (cv == null || cv == ev || cv.equals(ev)) {
1176	>	oldVal = ev;
1177	>	if ((e.val = v) == null) {
1178	>	deleted = true;
1179	>	Node en = e.next;
1180	>	if (pred != null)
1181	>	pred.next = en;
1182	>	else
1183	>	setTabAt(tab, i, en);
1184	>	}
1185	>	}
1186	>	break;
1187	>	}
1188	>	pred = e;
1189	>	if ((e = e.next) == null)
1190	>	break;
1191	>	}
1192	>	}
1193	>	} finally {
1194	>	if (!f.casHash(fh | LOCKED, fh)) {
1195	>	f.hash = fh;
1196	>	synchronized (f) { f.notifyAll(); };
1197	>	}
1198	>	}
1199	>	if (validated) {
1200	>	if (deleted)
1201	>	counter.add(-1L);
1202	>	break;
1203	>	}
1204		}
377	–	return oldValue;
1205		}
1206	+	return oldVal;
1207	+	}
1208
1209	<	/**
1210	<	* Doubles size of table and repacks entries, also adding the
1211	<	* given node to new table
1212	<	*/
1213	<	@SuppressWarnings("unchecked")
1214	<	private void rehash(HashEntry<K,V> node) {
1215	<	/*
1216	<	* Reclassify nodes in each list to new table.  Because we
1217	<	* are using power-of-two expansion, the elements from
1218	<	* each bin must either stay at same index, or move with a
1219	<	* power of two offset. We eliminate unnecessary node
1220	<	* creation by catching cases where old nodes can be
1221	<	* reused because their next fields won't change.
1222	<	* Statistically, at the default threshold, only about
1223	<	* one-sixth of them need cloning when a table
1224	<	* doubles. The nodes they replace will be garbage
1225	<	* collectable as soon as they are no longer referenced by
1226	<	* any reader thread that may be in the midst of
1227	<	* concurrently traversing table. Entry accesses use plain
1228	<	* array indexing because they are followed by volatile
1229	<	* table write.
1230	<	*/
1231	<	HashEntry<K,V>[] oldTable = table;
1232	<	int oldCapacity = oldTable.length;
1233	<	int newCapacity = oldCapacity << 1;
1234	<	threshold = (int)(newCapacity * loadFactor);
1235	<	HashEntry<K,V>[] newTable =
1236	<	(HashEntry<K,V>[]) new HashEntry<?,?>[newCapacity];
1237	<	int sizeMask = newCapacity - 1;
1238	<	for (int i = 0; i < oldCapacity ; i++) {
1239	<	HashEntry<K,V> e = oldTable[i];
1240	<	if (e != null) {
1241	<	HashEntry<K,V> next = e.next;
1242	<	int idx = e.hash & sizeMask;
1243	<	if (next == null)   //  Single node on list
1244	<	newTable[idx] = e;
1245	<	else { // Reuse consecutive sequence at same slot
1246	<	HashEntry<K,V> lastRun = e;
1247	<	int lastIdx = idx;
1248	<	for (HashEntry<K,V> last = next;
1249	<	last != null;
1250	<	last = last.next) {
1251	<	int k = last.hash & sizeMask;
1252	<	if (k != lastIdx) {
1253	<	lastIdx = k;
1254	<	lastRun = last;
1255	<	}
1256	<	}
1257	<	newTable[lastIdx] = lastRun;
1258	<	// Clone remaining nodes
1259	<	for (HashEntry<K,V> p = e; p != lastRun; p = p.next) {
1260	<	V v = p.value;
1261	<	int h = p.hash;
1262	<	int k = h & sizeMask;
1263	<	HashEntry<K,V> n = newTable[k];
1264	<	newTable[k] = new HashEntry<K,V>(h, p.key, v, n);
1265	<	}
1266	<	}
1267	<	}
1268	<	}
1269	<	int nodeIndex = node.hash & sizeMask; // add the new node
1270	<	node.setNext(newTable[nodeIndex]);
1271	<	newTable[nodeIndex] = node;
1272	<	table = newTable;
1273	<	}
1274	<
1275	<	/**
1276	<	* Scans for a node containing given key while trying to
1277	<	* acquire lock, creating and returning one if not found. Upon
1278	<	* return, guarantees that lock is held. Unlike in most
1279	<	* methods, calls to method equals are not screened: Since
1280	<	* traversal speed doesn't matter, we might as well help warm
1281	<	* up the associated code and accesses as well.
1282	<	*
1283	<	* @return a new node if key not found, else null
1284	<	*/
1285	<	private HashEntry<K,V> scanAndLockForPut(K key, int hash, V value) {
1286	<	HashEntry<K,V> first = entryForHash(this, hash);
1287	<	HashEntry<K,V> e = first;
1288	<	HashEntry<K,V> node = null;
1289	<	int retries = -1; // negative while locating node
1290	<	while (!tryLock()) {
1291	<	HashEntry<K,V> f; // to recheck first below
1292	<	if (retries < 0) {
1293	<	if (e == null) {
1294	<	if (node == null) // speculatively create node
1295	<	node = new HashEntry<K,V>(hash, key, value, null);
1296	<	retries = 0;
1209	>	/*
1210	>	* Internal versions of the six insertion methods, each a
1211	>	* little more complicated than the last. All have
1212	>	* the same basic structure as the first (internalPut):
1213	>	*  1. If table uninitialized, create
1214	>	*  2. If bin empty, try to CAS new node
1215	>	*  3. If bin stale, use new table
1216	>	*  4. if bin converted to TreeBin, validate and relay to TreeBin methods
1217	>	*  5. Lock and validate; if valid, scan and add or update
1218	>	*
1219	>	* The others interweave other checks and/or alternative actions:
1220	>	*  * Plain put checks for and performs resize after insertion.
1221	>	*  * putIfAbsent prescans for mapping without lock (and fails to add
1222	>	*    if present), which also makes pre-emptive resize checks worthwhile.
1223	>	*  * computeIfAbsent extends form used in putIfAbsent with additional
1224	>	*    mechanics to deal with, calls, potential exceptions and null
1225	>	*    returns from function call.
1226	>	*  * compute uses the same function-call mechanics, but without
1227	>	*    the prescans
1228	>	*  * merge acts as putIfAbsent in the absent case, but invokes the
1229	>	*    update function if present
1230	>	*  * putAll attempts to pre-allocate enough table space
1231	>	*    and more lazily performs count updates and checks.
1232	>	*
1233	>	* Someday when details settle down a bit more, it might be worth
1234	>	* some factoring to reduce sprawl.
1235	>	*/
1236	>
1237	>	/** Implementation for put */
1238	>	private final Object internalPut(Object k, Object v) {
1239	>	int h = spread(k.hashCode());
1240	>	int count = 0;
1241	>	for (Node[] tab = table;;) {
1242	>	int i; Node f; int fh; Object fk;
1243	>	if (tab == null)
1244	>	tab = initTable();
1245	>	else if ((f = tabAt(tab, i = (tab.length - 1) & h)) == null) {
1246	>	if (casTabAt(tab, i, null, new Node(h, k, v, null)))
1247	>	break;                   // no lock when adding to empty bin
1248	>	}
1249	>	else if ((fh = f.hash) == MOVED) {
1250	>	if ((fk = f.key) instanceof TreeBin) {
1251	>	TreeBin t = (TreeBin)fk;
1252	>	Object oldVal = null;
1253	>	t.acquire(0);
1254	>	try {
1255	>	if (tabAt(tab, i) == f) {
1256	>	count = 2;
1257	>	TreeNode p = t.putTreeNode(h, k, v);
1258	>	if (p != null) {
1259	>	oldVal = p.val;
1260	>	p.val = v;
1261	>	}
1262	>	}
1263	>	} finally {
1264	>	t.release(0);
1265	>	}
1266	>	if (count != 0) {
1267	>	if (oldVal != null)
1268	>	return oldVal;
1269	>	break;
1270	>	}
1271	>	}
1272	>	else
1273	>	tab = (Node[])fk;
1274	>	}
1275	>	else if ((fh & LOCKED) != 0) {
1276	>	checkForResize();
1277	>	f.tryAwaitLock(tab, i);
1278	>	}
1279	>	else if (f.casHash(fh, fh | LOCKED)) {
1280	>	Object oldVal = null;
1281	>	try {                        // needed in case equals() throws
1282	>	if (tabAt(tab, i) == f) {
1283	>	count = 1;
1284	>	for (Node e = f;; ++count) {
1285	>	Object ek, ev;
1286	>	if ((e.hash & HASH_BITS) == h &&
1287	>	(ev = e.val) != null &&
1288	>	((ek = e.key) == k || k.equals(ek))) {
1289	>	oldVal = ev;
1290	>	e.val = v;
1291	>	break;
1292	>	}
1293	>	Node last = e;
1294	>	if ((e = e.next) == null) {
1295	>	last.next = new Node(h, k, v, null);
1296	>	if (count >= TREE_THRESHOLD)
1297	>	replaceWithTreeBin(tab, i, k);
1298	>	break;
1299	>	}
1300	>	}
1301	>	}
1302	>	} finally {                  // unlock and signal if needed
1303	>	if (!f.casHash(fh | LOCKED, fh)) {
1304	>	f.hash = fh;
1305	>	synchronized (f) { f.notifyAll(); };
1306		}
469	–	else if (key.equals(e.key))
470	–	retries = 0;
471	–	else
472	–	e = e.next;
1307		}
1308	<	else if (++retries > MAX_SCAN_RETRIES) {
1309	<	lock();
1308	>	if (count != 0) {
1309	>	if (oldVal != null)
1310	>	return oldVal;
1311	>	if (tab.length <= 64)
1312	>	count = 2;
1313		break;
1314		}
1315	<	else if ((retries & 1) == 0 &&
1316	<	(f = entryForHash(this, hash)) != first) {
1317	<	e = first = f; // re-traverse if entry changed
1318	<	retries = -1;
1315	>	}
1316	>	}
1317	>	counter.add(1L);
1318	>	if (count > 1)
1319	>	checkForResize();
1320	>	return null;
1321	>	}
1322	>
1323	>	/** Implementation for putIfAbsent */
1324	>	private final Object internalPutIfAbsent(Object k, Object v) {
1325	>	int h = spread(k.hashCode());
1326	>	int count = 0;
1327	>	for (Node[] tab = table;;) {
1328	>	int i; Node f; int fh; Object fk, fv;
1329	>	if (tab == null)
1330	>	tab = initTable();
1331	>	else if ((f = tabAt(tab, i = (tab.length - 1) & h)) == null) {
1332	>	if (casTabAt(tab, i, null, new Node(h, k, v, null)))
1333	>	break;
1334	>	}
1335	>	else if ((fh = f.hash) == MOVED) {
1336	>	if ((fk = f.key) instanceof TreeBin) {
1337	>	TreeBin t = (TreeBin)fk;
1338	>	Object oldVal = null;
1339	>	t.acquire(0);
1340	>	try {
1341	>	if (tabAt(tab, i) == f) {
1342	>	count = 2;
1343	>	TreeNode p = t.putTreeNode(h, k, v);
1344	>	if (p != null)
1345	>	oldVal = p.val;
1346	>	}
1347	>	} finally {
1348	>	t.release(0);
1349	>	}
1350	>	if (count != 0) {
1351	>	if (oldVal != null)
1352	>	return oldVal;
1353	>	break;
1354	>	}
1355	>	}
1356	>	else
1357	>	tab = (Node[])fk;
1358	>	}
1359	>	else if ((fh & HASH_BITS) == h && (fv = f.val) != null &&
1360	>	((fk = f.key) == k || k.equals(fk)))
1361	>	return fv;
1362	>	else {
1363	>	Node g = f.next;
1364	>	if (g != null) { // at least 2 nodes -- search and maybe resize
1365	>	for (Node e = g;;) {
1366	>	Object ek, ev;
1367	>	if ((e.hash & HASH_BITS) == h && (ev = e.val) != null &&
1368	>	((ek = e.key) == k || k.equals(ek)))
1369	>	return ev;
1370	>	if ((e = e.next) == null) {
1371	>	checkForResize();
1372	>	break;
1373	>	}
1374	>	}
1375	>	}
1376	>	if (((fh = f.hash) & LOCKED) != 0) {
1377	>	checkForResize();
1378	>	f.tryAwaitLock(tab, i);
1379	>	}
1380	>	else if (tabAt(tab, i) == f && f.casHash(fh, fh | LOCKED)) {
1381	>	Object oldVal = null;
1382	>	try {
1383	>	if (tabAt(tab, i) == f) {
1384	>	count = 1;
1385	>	for (Node e = f;; ++count) {
1386	>	Object ek, ev;
1387	>	if ((e.hash & HASH_BITS) == h &&
1388	>	(ev = e.val) != null &&
1389	>	((ek = e.key) == k || k.equals(ek))) {
1390	>	oldVal = ev;
1391	>	break;
1392	>	}
1393	>	Node last = e;
1394	>	if ((e = e.next) == null) {
1395	>	last.next = new Node(h, k, v, null);
1396	>	if (count >= TREE_THRESHOLD)
1397	>	replaceWithTreeBin(tab, i, k);
1398	>	break;
1399	>	}
1400	>	}
1401	>	}
1402	>	} finally {
1403	>	if (!f.casHash(fh | LOCKED, fh)) {
1404	>	f.hash = fh;
1405	>	synchronized (f) { f.notifyAll(); };
1406	>	}
1407	>	}
1408	>	if (count != 0) {
1409	>	if (oldVal != null)
1410	>	return oldVal;
1411	>	if (tab.length <= 64)
1412	>	count = 2;
1413	>	break;
1414	>	}
1415		}
1416		}
484	–	return node;
1417		}
1418	+	counter.add(1L);
1419	+	if (count > 1)
1420	+	checkForResize();
1421	+	return null;
1422	+	}
1423
1424	<	/**
1425	<	* Scans for a node containing the given key while trying to
1426	<	* acquire lock for a remove or replace operation. Upon
1427	<	* return, guarantees that lock is held.  Note that we must
1428	<	* lock even if the key is not found, to ensure sequential
1429	<	* consistency of updates.
1430	<	*/
1431	<	private void scanAndLock(Object key, int hash) {
1432	<	// similar to but simpler than scanAndLockForPut
1433	<	HashEntry<K,V> first = entryForHash(this, hash);
1434	<	HashEntry<K,V> e = first;
1435	<	int retries = -1;
1436	<	while (!tryLock()) {
1437	<	HashEntry<K,V> f;
1438	<	if (retries < 0) {
1439	<	if (e == null || key.equals(e.key))
1440	<	retries = 0;
1441	<	else
1442	<	e = e.next;
1424	>	/** Implementation for computeIfAbsent */
1425	>	private final Object internalComputeIfAbsent(K k,
1426	>	Fun<? super K, ?> mf) {
1427	>	int h = spread(k.hashCode());
1428	>	Object val = null;
1429	>	int count = 0;
1430	>	for (Node[] tab = table;;) {
1431	>	Node f; int i, fh; Object fk, fv;
1432	>	if (tab == null)
1433	>	tab = initTable();
1434	>	else if ((f = tabAt(tab, i = (tab.length - 1) & h)) == null) {
1435	>	Node node = new Node(fh = h | LOCKED, k, null, null);
1436	>	if (casTabAt(tab, i, null, node)) {
1437	>	count = 1;
1438	>	try {
1439	>	if ((val = mf.apply(k)) != null)
1440	>	node.val = val;
1441	>	} finally {
1442	>	if (val == null)
1443	>	setTabAt(tab, i, null);
1444	>	if (!node.casHash(fh, h)) {
1445	>	node.hash = h;
1446	>	synchronized (node) { node.notifyAll(); };
1447	>	}
1448	>	}
1449		}
1450	<	else if (++retries > MAX_SCAN_RETRIES) {
508	<	lock();
1450	>	if (count != 0)
1451		break;
1452	+	}
1453	+	else if ((fh = f.hash) == MOVED) {
1454	+	if ((fk = f.key) instanceof TreeBin) {
1455	+	TreeBin t = (TreeBin)fk;
1456	+	boolean added = false;
1457	+	t.acquire(0);
1458	+	try {
1459	+	if (tabAt(tab, i) == f) {
1460	+	count = 1;
1461	+	TreeNode p = t.getTreeNode(h, k, t.root);
1462	+	if (p != null)
1463	+	val = p.val;
1464	+	else if ((val = mf.apply(k)) != null) {
1465	+	added = true;
1466	+	count = 2;
1467	+	t.putTreeNode(h, k, val);
1468	+	}
1469	+	}
1470	+	} finally {
1471	+	t.release(0);
1472	+	}
1473	+	if (count != 0) {
1474	+	if (!added)
1475	+	return val;
1476	+	break;
1477	+	}
1478		}
1479	<	else if ((retries & 1) == 0 &&
1480	<	(f = entryForHash(this, hash)) != first) {
1481	<	e = first = f;
1482	<	retries = -1;
1479	>	else
1480	>	tab = (Node[])fk;
1481	>	}
1482	>	else if ((fh & HASH_BITS) == h && (fv = f.val) != null &&
1483	>	((fk = f.key) == k || k.equals(fk)))
1484	>	return fv;
1485	>	else {
1486	>	Node g = f.next;
1487	>	if (g != null) {
1488	>	for (Node e = g;;) {
1489	>	Object ek, ev;
1490	>	if ((e.hash & HASH_BITS) == h && (ev = e.val) != null &&
1491	>	((ek = e.key) == k || k.equals(ek)))
1492	>	return ev;
1493	>	if ((e = e.next) == null) {
1494	>	checkForResize();
1495	>	break;
1496	>	}
1497	>	}
1498	>	}
1499	>	if (((fh = f.hash) & LOCKED) != 0) {
1500	>	checkForResize();
1501	>	f.tryAwaitLock(tab, i);
1502	>	}
1503	>	else if (tabAt(tab, i) == f && f.casHash(fh, fh | LOCKED)) {
1504	>	boolean added = false;
1505	>	try {
1506	>	if (tabAt(tab, i) == f) {
1507	>	count = 1;
1508	>	for (Node e = f;; ++count) {
1509	>	Object ek, ev;
1510	>	if ((e.hash & HASH_BITS) == h &&
1511	>	(ev = e.val) != null &&
1512	>	((ek = e.key) == k || k.equals(ek))) {
1513	>	val = ev;
1514	>	break;
1515	>	}
1516	>	Node last = e;
1517	>	if ((e = e.next) == null) {
1518	>	if ((val = mf.apply(k)) != null) {
1519	>	added = true;
1520	>	last.next = new Node(h, k, val, null);
1521	>	if (count >= TREE_THRESHOLD)
1522	>	replaceWithTreeBin(tab, i, k);
1523	>	}
1524	>	break;
1525	>	}
1526	>	}
1527	>	}
1528	>	} finally {
1529	>	if (!f.casHash(fh | LOCKED, fh)) {
1530	>	f.hash = fh;
1531	>	synchronized (f) { f.notifyAll(); };
1532	>	}
1533	>	}
1534	>	if (count != 0) {
1535	>	if (!added)
1536	>	return val;
1537	>	if (tab.length <= 64)
1538	>	count = 2;
1539	>	break;
1540	>	}
1541		}
1542		}
1543		}
1544	+	if (val != null) {
1545	+	counter.add(1L);
1546	+	if (count > 1)
1547	+	checkForResize();
1548	+	}
1549	+	return val;
1550	+	}
1551
1552	<	/**
1553	<	* Remove; match on key only if value null, else match both.
1554	<	*/
1555	<	final V remove(Object key, int hash, Object value) {
1556	<	if (!tryLock())
1557	<	scanAndLock(key, hash);
1558	<	V oldValue = null;
1559	<	try {
1560	<	HashEntry<K,V>[] tab = table;
1561	<	int index = (tab.length - 1) & hash;
1562	<	HashEntry<K,V> e = entryAt(tab, index);
1563	<	HashEntry<K,V> pred = null;
1564	<	while (e != null) {
1565	<	K k;
1566	<	HashEntry<K,V> next = e.next;
1567	<	if ((k = e.key) == key ||
1568	<	(e.hash == hash && key.equals(k))) {
1569	<	V v = e.value;
1570	<	if (value == null || value == v || value.equals(v)) {
1571	<	if (pred == null)
1572	<	setEntryAt(tab, index, next);
1573	<	else
1574	<	pred.setNext(next);
1575	<	++modCount;
1576	<	--count;
1577	<	oldValue = v;
1552	>	/** Implementation for compute */
1553	>	@SuppressWarnings("unchecked")
1554	>	private final Object internalCompute(K k, boolean onlyIfPresent,
1555	>	BiFun<? super K, ? super V, ? extends V> mf) {
1556	>	int h = spread(k.hashCode());
1557	>	Object val = null;
1558	>	int delta = 0;
1559	>	int count = 0;
1560	>	for (Node[] tab = table;;) {
1561	>	Node f; int i, fh; Object fk;
1562	>	if (tab == null)
1563	>	tab = initTable();
1564	>	else if ((f = tabAt(tab, i = (tab.length - 1) & h)) == null) {
1565	>	if (onlyIfPresent)
1566	>	break;
1567	>	Node node = new Node(fh = h | LOCKED, k, null, null);
1568	>	if (casTabAt(tab, i, null, node)) {
1569	>	try {
1570	>	count = 1;
1571	>	if ((val = mf.apply(k, null)) != null) {
1572	>	node.val = val;
1573	>	delta = 1;
1574	>	}
1575	>	} finally {
1576	>	if (delta == 0)
1577	>	setTabAt(tab, i, null);
1578	>	if (!node.casHash(fh, h)) {
1579	>	node.hash = h;
1580	>	synchronized (node) { node.notifyAll(); };
1581		}
1582	+	}
1583	+	}
1584	+	if (count != 0)
1585	+	break;
1586	+	}
1587	+	else if ((fh = f.hash) == MOVED) {
1588	+	if ((fk = f.key) instanceof TreeBin) {
1589	+	TreeBin t = (TreeBin)fk;
1590	+	t.acquire(0);
1591	+	try {
1592	+	if (tabAt(tab, i) == f) {
1593	+	count = 1;
1594	+	TreeNode p = t.getTreeNode(h, k, t.root);
1595	+	Object pv = (p == null) ? null : p.val;
1596	+	if ((val = mf.apply(k, (V)pv)) != null) {
1597	+	if (p != null)
1598	+	p.val = val;
1599	+	else {
1600	+	count = 2;
1601	+	delta = 1;
1602	+	t.putTreeNode(h, k, val);
1603	+	}
1604	+	}
1605	+	else if (p != null) {
1606	+	delta = -1;
1607	+	t.deleteTreeNode(p);
1608	+	}
1609	+	}
1610	+	} finally {
1611	+	t.release(0);
1612	+	}
1613	+	if (count != 0)
1614		break;
1615	+	}
1616	+	else
1617	+	tab = (Node[])fk;
1618	+	}
1619	+	else if ((fh & LOCKED) != 0) {
1620	+	checkForResize();
1621	+	f.tryAwaitLock(tab, i);
1622	+	}
1623	+	else if (f.casHash(fh, fh | LOCKED)) {
1624	+	try {
1625	+	if (tabAt(tab, i) == f) {
1626	+	count = 1;
1627	+	for (Node e = f, pred = null;; ++count) {
1628	+	Object ek, ev;
1629	+	if ((e.hash & HASH_BITS) == h &&
1630	+	(ev = e.val) != null &&
1631	+	((ek = e.key) == k || k.equals(ek))) {
1632	+	val = mf.apply(k, (V)ev);
1633	+	if (val != null)
1634	+	e.val = val;
1635	+	else {
1636	+	delta = -1;
1637	+	Node en = e.next;
1638	+	if (pred != null)
1639	+	pred.next = en;
1640	+	else
1641	+	setTabAt(tab, i, en);
1642	+	}
1643	+	break;
1644	+	}
1645	+	pred = e;
1646	+	if ((e = e.next) == null) {
1647	+	if (!onlyIfPresent && (val = mf.apply(k, null)) != null) {
1648	+	pred.next = new Node(h, k, val, null);
1649	+	delta = 1;
1650	+	if (count >= TREE_THRESHOLD)
1651	+	replaceWithTreeBin(tab, i, k);
1652	+	}
1653	+	break;
1654	+	}
1655	+	}
1656	+	}
1657	+	} finally {
1658	+	if (!f.casHash(fh | LOCKED, fh)) {
1659	+	f.hash = fh;
1660	+	synchronized (f) { f.notifyAll(); };
1661		}
548	–	pred = e;
549	–	e = next;
1662		}
1663	<	} finally {
1664	<	unlock();
1663	>	if (count != 0) {
1664	>	if (tab.length <= 64)
1665	>	count = 2;
1666	>	break;
1667	>	}
1668		}
554	–	return oldValue;
1669		}
1670	+	if (delta != 0) {
1671	+	counter.add((long)delta);
1672	+	if (count > 1)
1673	+	checkForResize();
1674	+	}
1675	+	return val;
1676	+	}
1677
1678	<	final boolean replace(K key, int hash, V oldValue, V newValue) {
1679	<	if (!tryLock())
1680	<	scanAndLock(key, hash);
1681	<	boolean replaced = false;
1682	<	try {
1683	<	HashEntry<K,V> e;
1684	<	for (e = entryForHash(this, hash); e != null; e = e.next) {
1685	<	K k;
1686	<	if ((k = e.key) == key ||
1687	<	(e.hash == hash && key.equals(k))) {
1688	<	if (oldValue.equals(e.value)) {
1689	<	e.value = newValue;
1690	<	++modCount;
1691	<	replaced = true;
1678	>	/** Implementation for merge */
1679	>	@SuppressWarnings("unchecked")
1680	>	private final Object internalMerge(K k, V v,
1681	>	BiFun<? super V, ? super V, ? extends V> mf) {
1682	>	int h = spread(k.hashCode());
1683	>	Object val = null;
1684	>	int delta = 0;
1685	>	int count = 0;
1686	>	for (Node[] tab = table;;) {
1687	>	int i; Node f; int fh; Object fk, fv;
1688	>	if (tab == null)
1689	>	tab = initTable();
1690	>	else if ((f = tabAt(tab, i = (tab.length - 1) & h)) == null) {
1691	>	if (casTabAt(tab, i, null, new Node(h, k, v, null))) {
1692	>	delta = 1;
1693	>	val = v;
1694	>	break;
1695	>	}
1696	>	}
1697	>	else if ((fh = f.hash) == MOVED) {
1698	>	if ((fk = f.key) instanceof TreeBin) {
1699	>	TreeBin t = (TreeBin)fk;
1700	>	t.acquire(0);
1701	>	try {
1702	>	if (tabAt(tab, i) == f) {
1703	>	count = 1;
1704	>	TreeNode p = t.getTreeNode(h, k, t.root);
1705	>	val = (p == null) ? v : mf.apply((V)p.val, v);
1706	>	if (val != null) {
1707	>	if (p != null)
1708	>	p.val = val;
1709	>	else {
1710	>	count = 2;
1711	>	delta = 1;
1712	>	t.putTreeNode(h, k, val);
1713	>	}
1714	>	}
1715	>	else if (p != null) {
1716	>	delta = -1;
1717	>	t.deleteTreeNode(p);
1718	>	}
1719		}
1720	+	} finally {
1721	+	t.release(0);
1722	+	}
1723	+	if (count != 0)
1724		break;
1725	+	}
1726	+	else
1727	+	tab = (Node[])fk;
1728	+	}
1729	+	else if ((fh & LOCKED) != 0) {
1730	+	checkForResize();
1731	+	f.tryAwaitLock(tab, i);
1732	+	}
1733	+	else if (f.casHash(fh, fh | LOCKED)) {
1734	+	try {
1735	+	if (tabAt(tab, i) == f) {
1736	+	count = 1;
1737	+	for (Node e = f, pred = null;; ++count) {
1738	+	Object ek, ev;
1739	+	if ((e.hash & HASH_BITS) == h &&
1740	+	(ev = e.val) != null &&
1741	+	((ek = e.key) == k || k.equals(ek))) {
1742	+	val = mf.apply(v, (V)ev);
1743	+	if (val != null)
1744	+	e.val = val;
1745	+	else {
1746	+	delta = -1;
1747	+	Node en = e.next;
1748	+	if (pred != null)
1749	+	pred.next = en;
1750	+	else
1751	+	setTabAt(tab, i, en);
1752	+	}
1753	+	break;
1754	+	}
1755	+	pred = e;
1756	+	if ((e = e.next) == null) {
1757	+	val = v;
1758	+	pred.next = new Node(h, k, val, null);
1759	+	delta = 1;
1760	+	if (count >= TREE_THRESHOLD)
1761	+	replaceWithTreeBin(tab, i, k);
1762	+	break;
1763	+	}
1764	+	}
1765	+	}
1766	+	} finally {
1767	+	if (!f.casHash(fh | LOCKED, fh)) {
1768	+	f.hash = fh;
1769	+	synchronized (f) { f.notifyAll(); };
1770	+	}
1771	+	}
1772	+	if (count != 0) {
1773	+	if (tab.length <= 64)
1774	+	count = 2;
1775	+	break;
1776	+	}
1777	+	}
1778	+	}
1779	+	if (delta != 0) {
1780	+	counter.add((long)delta);
1781	+	if (count > 1)
1782	+	checkForResize();
1783	+	}
1784	+	return val;
1785	+	}
1786	+
1787	+	/** Implementation for putAll */
1788	+	private final void internalPutAll(Map<?, ?> m) {
1789	+	tryPresize(m.size());
1790	+	long delta = 0L;     // number of uncommitted additions
1791	+	boolean npe = false; // to throw exception on exit for nulls
1792	+	try {                // to clean up counts on other exceptions
1793	+	for (Map.Entry<?, ?> entry : m.entrySet()) {
1794	+	Object k, v;
1795	+	if (entry == null || (k = entry.getKey()) == null ||
1796	+	(v = entry.getValue()) == null) {
1797	+	npe = true;
1798	+	break;
1799	+	}
1800	+	int h = spread(k.hashCode());
1801	+	for (Node[] tab = table;;) {
1802	+	int i; Node f; int fh; Object fk;
1803	+	if (tab == null)
1804	+	tab = initTable();
1805	+	else if ((f = tabAt(tab, i = (tab.length - 1) & h)) == null){
1806	+	if (casTabAt(tab, i, null, new Node(h, k, v, null))) {
1807	+	++delta;
1808	+	break;
1809	+	}
1810	+	}
1811	+	else if ((fh = f.hash) == MOVED) {
1812	+	if ((fk = f.key) instanceof TreeBin) {
1813	+	TreeBin t = (TreeBin)fk;
1814	+	boolean validated = false;
1815	+	t.acquire(0);
1816	+	try {
1817	+	if (tabAt(tab, i) == f) {
1818	+	validated = true;
1819	+	TreeNode p = t.getTreeNode(h, k, t.root);
1820	+	if (p != null)
1821	+	p.val = v;
1822	+	else {
1823	+	t.putTreeNode(h, k, v);
1824	+	++delta;
1825	+	}
1826	+	}
1827	+	} finally {
1828	+	t.release(0);
1829	+	}
1830	+	if (validated)
1831	+	break;
1832	+	}
1833	+	else
1834	+	tab = (Node[])fk;
1835	+	}
1836	+	else if ((fh & LOCKED) != 0) {
1837	+	counter.add(delta);
1838	+	delta = 0L;
1839	+	checkForResize();
1840	+	f.tryAwaitLock(tab, i);
1841	+	}
1842	+	else if (f.casHash(fh, fh | LOCKED)) {
1843	+	int count = 0;
1844	+	try {
1845	+	if (tabAt(tab, i) == f) {
1846	+	count = 1;
1847	+	for (Node e = f;; ++count) {
1848	+	Object ek, ev;
1849	+	if ((e.hash & HASH_BITS) == h &&
1850	+	(ev = e.val) != null &&
1851	+	((ek = e.key) == k || k.equals(ek))) {
1852	+	e.val = v;
1853	+	break;
1854	+	}
1855	+	Node last = e;
1856	+	if ((e = e.next) == null) {
1857	+	++delta;
1858	+	last.next = new Node(h, k, v, null);
1859	+	if (count >= TREE_THRESHOLD)
1860	+	replaceWithTreeBin(tab, i, k);
1861	+	break;
1862	+	}
1863	+	}
1864	+	}
1865	+	} finally {
1866	+	if (!f.casHash(fh | LOCKED, fh)) {
1867	+	f.hash = fh;
1868	+	synchronized (f) { f.notifyAll(); };
1869	+	}
1870	+	}
1871	+	if (count != 0) {
1872	+	if (count > 1) {
1873	+	counter.add(delta);
1874	+	delta = 0L;
1875	+	checkForResize();
1876	+	}
1877	+	break;
1878	+	}
1879		}
1880		}
575	–	} finally {
576	–	unlock();
1881		}
1882	<	return replaced;
1882	>	} finally {
1883	>	if (delta != 0)
1884	>	counter.add(delta);
1885		}
1886	+	if (npe)
1887	+	throw new NullPointerException();
1888	+	}
1889
1890	<	final V replace(K key, int hash, V value) {
1891	<	if (!tryLock())
1892	<	scanAndLock(key, hash);
1893	<	V oldValue = null;
1894	<	try {
1895	<	HashEntry<K,V> e;
1896	<	for (e = entryForHash(this, hash); e != null; e = e.next) {
1897	<	K k;
1898	<	if ((k = e.key) == key ||
1899	<	(e.hash == hash && key.equals(k))) {
1900	<	oldValue = e.value;
1901	<	e.value = value;
1902	<	++modCount;
1903	<	break;
1890	>	/* ---------------- Table Initialization and Resizing -------------- */
1891	>
1892	>	/**
1893	>	* Returns a power of two table size for the given desired capacity.
1894	>	* See Hackers Delight, sec 3.2
1895	>	*/
1896	>	private static final int tableSizeFor(int c) {
1897	>	int n = c - 1;
1898	>	n |= n >>> 1;
1899	>	n |= n >>> 2;
1900	>	n |= n >>> 4;
1901	>	n |= n >>> 8;
1902	>	n |= n >>> 16;
1903	>	return (n < 0) ? 1 : (n >= MAXIMUM_CAPACITY) ? MAXIMUM_CAPACITY : n + 1;
1904	>	}
1905	>
1906	>	/**
1907	>	* Initializes table, using the size recorded in sizeCtl.
1908	>	*/
1909	>	private final Node[] initTable() {
1910	>	Node[] tab; int sc;
1911	>	while ((tab = table) == null) {
1912	>	if ((sc = sizeCtl) < 0)
1913	>	Thread.yield(); // lost initialization race; just spin
1914	>	else if (UNSAFE.compareAndSwapInt(this, sizeCtlOffset, sc, -1)) {
1915	>	try {
1916	>	if ((tab = table) == null) {
1917	>	int n = (sc > 0) ? sc : DEFAULT_CAPACITY;
1918	>	tab = table = new Node[n];
1919	>	sc = n - (n >>> 2);
1920		}
1921	+	} finally {
1922	+	sizeCtl = sc;
1923		}
1924	<	} finally {
598	<	unlock();
1924	>	break;
1925		}
600	–	return oldValue;
1926		}
1927	+	return tab;
1928	+	}
1929
1930	<	final void clear() {
1931	<	lock();
1930	>	/**
1931	>	* If table is too small and not already resizing, creates next
1932	>	* table and transfers bins.  Rechecks occupancy after a transfer
1933	>	* to see if another resize is already needed because resizings
1934	>	* are lagging additions.
1935	>	*/
1936	>	private final void checkForResize() {
1937	>	Node[] tab; int n, sc;
1938	>	while ((tab = table) != null &&
1939	>	(n = tab.length) < MAXIMUM_CAPACITY &&
1940	>	(sc = sizeCtl) >= 0 && counter.sum() >= (long)sc &&
1941	>	UNSAFE.compareAndSwapInt(this, sizeCtlOffset, sc, -1)) {
1942		try {
1943	<	HashEntry<K,V>[] tab = table;
1944	<	for (int i = 0; i < tab.length ; i++)
1945	<	setEntryAt(tab, i, null);
1946	<	++modCount;
610	<	count = 0;
1943	>	if (tab == table) {
1944	>	table = rebuild(tab);
1945	>	sc = (n << 1) - (n >>> 1);
1946	>	}
1947		} finally {
1948	<	unlock();
1948	>	sizeCtl = sc;
1949		}
1950		}
1951		}
1952
617	–	// Accessing segments
618	–
1953		/**
1954	<	* Gets the jth element of given segment array (if nonnull) with
1955	<	* volatile element access semantics via Unsafe. (The null check
1956	<	* can trigger harmlessly only during deserialization.) Note:
623	<	* because each element of segments array is set only once (using
624	<	* fully ordered writes), some performance-sensitive methods rely
625	<	* on this method only as a recheck upon null reads.
1954	>	* Tries to presize table to accommodate the given number of elements.
1955	>	*
1956	>	* @param size number of elements (doesn't need to be perfectly accurate)
1957		*/
1958	<	@SuppressWarnings("unchecked")
1959	<	static final <K,V> Segment<K,V> segmentAt(Segment<K,V>[] ss, int j) {
1960	<	long u = (j << SSHIFT) + SBASE;
1961	<	return ss == null ? null :
1962	<	(Segment<K,V>) UNSAFE.getObjectVolatile(ss, u);
1958	>	private final void tryPresize(int size) {
1959	>	int c = (size >= (MAXIMUM_CAPACITY >>> 1)) ? MAXIMUM_CAPACITY :
1960	>	tableSizeFor(size + (size >>> 1) + 1);
1961	>	int sc;
1962	>	while ((sc = sizeCtl) >= 0) {
1963	>	Node[] tab = table; int n;
1964	>	if (tab == null || (n = tab.length) == 0) {
1965	>	n = (sc > c) ? sc : c;
1966	>	if (UNSAFE.compareAndSwapInt(this, sizeCtlOffset, sc, -1)) {
1967	>	try {
1968	>	if (table == tab) {
1969	>	table = new Node[n];
1970	>	sc = n - (n >>> 2);
1971	>	}
1972	>	} finally {
1973	>	sizeCtl = sc;
1974	>	}
1975	>	}
1976	>	}
1977	>	else if (c <= sc || n >= MAXIMUM_CAPACITY)
1978	>	break;
1979	>	else if (UNSAFE.compareAndSwapInt(this, sizeCtlOffset, sc, -1)) {
1980	>	try {
1981	>	if (table == tab) {
1982	>	table = rebuild(tab);
1983	>	sc = (n << 1) - (n >>> 1);
1984	>	}
1985	>	} finally {
1986	>	sizeCtl = sc;
1987	>	}
1988	>	}
1989	>	}
1990		}
1991
1992	<	/**
1993	<	* Returns the segment for the given index, creating it and
1994	<	* recording in segment table (via CAS) if not already present.
1992	>	/*
1993	>	* Moves and/or copies the nodes in each bin to new table. See
1994	>	* above for explanation.
1995		*
1996	<	* @param k the index
639	<	* @return the segment
1996	>	* @return the new table
1997		*/
1998	<	@SuppressWarnings("unchecked")
1999	<	private Segment<K,V> ensureSegment(int k) {
2000	<	final Segment<K,V>[] ss = this.segments;
2001	<	long u = (k << SSHIFT) + SBASE; // raw offset
2002	<	Segment<K,V> seg;
2003	<	if ((seg = (Segment<K,V>)UNSAFE.getObjectVolatile(ss, u)) == null) {
2004	<	Segment<K,V> proto = ss[0]; // use segment 0 as prototype
2005	<	int cap = proto.table.length;
2006	<	float lf = proto.loadFactor;
2007	<	int threshold = (int)(cap * lf);
2008	<	HashEntry<K,V>[] tab = (HashEntry<K,V>[])new HashEntry<?,?>[cap];
2009	<	if ((seg = (Segment<K,V>)UNSAFE.getObjectVolatile(ss, u))
2010	<	== null) { // recheck
2011	<	Segment<K,V> s = new Segment<K,V>(lf, threshold, tab);
2012	<	while ((seg = (Segment<K,V>)UNSAFE.getObjectVolatile(ss, u))
2013	<	== null) {
2014	<	if (UNSAFE.compareAndSwapObject(ss, u, null, seg = s))
2015	<	break;
1998	>	private static final Node[] rebuild(Node[] tab) {
1999	>	int n = tab.length;
2000	>	Node[] nextTab = new Node[n << 1];
2001	>	Node fwd = new Node(MOVED, nextTab, null, null);
2002	>	int[] buffer = null;       // holds bins to revisit; null until needed
2003	>	Node rev = null;           // reverse forwarder; null until needed
2004	>	int nbuffered = 0;         // the number of bins in buffer list
2005	>	int bufferIndex = 0;       // buffer index of current buffered bin
2006	>	int bin = n - 1;           // current non-buffered bin or -1 if none
2007	>
2008	>	for (int i = bin;;) {      // start upwards sweep
2009	>	int fh; Node f;
2010	>	if ((f = tabAt(tab, i)) == null) {
2011	>	if (bin >= 0) {    // no lock needed (or available)
2012	>	if (!casTabAt(tab, i, f, fwd))
2013	>	continue;
2014	>	}
2015	>	else {             // transiently use a locked forwarding node
2016	>	Node g = new Node(MOVED|LOCKED, nextTab, null, null);
2017	>	if (!casTabAt(tab, i, f, g))
2018	>	continue;
2019	>	setTabAt(nextTab, i, null);
2020	>	setTabAt(nextTab, i + n, null);
2021	>	setTabAt(tab, i, fwd);
2022	>	if (!g.casHash(MOVED|LOCKED, MOVED)) {
2023	>	g.hash = MOVED;
2024	>	synchronized (g) { g.notifyAll(); }
2025	>	}
2026		}
2027		}
2028	+	else if ((fh = f.hash) == MOVED) {
2029	+	Object fk = f.key;
2030	+	if (fk instanceof TreeBin) {
2031	+	TreeBin t = (TreeBin)fk;
2032	+	boolean validated = false;
2033	+	t.acquire(0);
2034	+	try {
2035	+	if (tabAt(tab, i) == f) {
2036	+	validated = true;
2037	+	splitTreeBin(nextTab, i, t);
2038	+	setTabAt(tab, i, fwd);
2039	+	}
2040	+	} finally {
2041	+	t.release(0);
2042	+	}
2043	+	if (!validated)
2044	+	continue;
2045	+	}
2046	+	}
2047	+	else if ((fh & LOCKED) == 0 && f.casHash(fh, fh|LOCKED)) {
2048	+	boolean validated = false;
2049	+	try {              // split to lo and hi lists; copying as needed
2050	+	if (tabAt(tab, i) == f) {
2051	+	validated = true;
2052	+	splitBin(nextTab, i, f);
2053	+	setTabAt(tab, i, fwd);
2054	+	}
2055	+	} finally {
2056	+	if (!f.casHash(fh | LOCKED, fh)) {
2057	+	f.hash = fh;
2058	+	synchronized (f) { f.notifyAll(); };
2059	+	}
2060	+	}
2061	+	if (!validated)
2062	+	continue;
2063	+	}
2064	+	else {
2065	+	if (buffer == null) // initialize buffer for revisits
2066	+	buffer = new int[TRANSFER_BUFFER_SIZE];
2067	+	if (bin < 0 && bufferIndex > 0) {
2068	+	int j = buffer[--bufferIndex];
2069	+	buffer[bufferIndex] = i;
2070	+	i = j;         // swap with another bin
2071	+	continue;
2072	+	}
2073	+	if (bin < 0 || nbuffered >= TRANSFER_BUFFER_SIZE) {
2074	+	f.tryAwaitLock(tab, i);
2075	+	continue;      // no other options -- block
2076	+	}
2077	+	if (rev == null)   // initialize reverse-forwarder
2078	+	rev = new Node(MOVED, tab, null, null);
2079	+	if (tabAt(tab, i) != f || (f.hash & LOCKED) == 0)
2080	+	continue;      // recheck before adding to list
2081	+	buffer[nbuffered++] = i;
2082	+	setTabAt(nextTab, i, rev);     // install place-holders
2083	+	setTabAt(nextTab, i + n, rev);
2084	+	}
2085	+
2086	+	if (bin > 0)
2087	+	i = --bin;
2088	+	else if (buffer != null && nbuffered > 0) {
2089	+	bin = -1;
2090	+	i = buffer[bufferIndex = --nbuffered];
2091	+	}
2092	+	else
2093	+	return nextTab;
2094		}
662	–	return seg;
2095		}
2096
665	–	// Hash-based segment and entry accesses
666	–
2097		/**
2098	<	* Gets the segment for the given hash code.
2098	>	* Splits a normal bin with list headed by e into lo and hi parts;
2099	>	* installs in given table.
2100		*/
2101	<	@SuppressWarnings("unchecked")
2102	<	private Segment<K,V> segmentForHash(int h) {
2103	<	long u = (((h >>> segmentShift) & segmentMask) << SSHIFT) + SBASE;
2104	<	return (Segment<K,V>) UNSAFE.getObjectVolatile(segments, u);
2101	>	private static void splitBin(Node[] nextTab, int i, Node e) {
2102	>	int bit = nextTab.length >>> 1; // bit to split on
2103	>	int runBit = e.hash & bit;
2104	>	Node lastRun = e, lo = null, hi = null;
2105	>	for (Node p = e.next; p != null; p = p.next) {
2106	>	int b = p.hash & bit;
2107	>	if (b != runBit) {
2108	>	runBit = b;
2109	>	lastRun = p;
2110	>	}
2111	>	}
2112	>	if (runBit == 0)
2113	>	lo = lastRun;
2114	>	else
2115	>	hi = lastRun;
2116	>	for (Node p = e; p != lastRun; p = p.next) {
2117	>	int ph = p.hash & HASH_BITS;
2118	>	Object pk = p.key, pv = p.val;
2119	>	if ((ph & bit) == 0)
2120	>	lo = new Node(ph, pk, pv, lo);
2121	>	else
2122	>	hi = new Node(ph, pk, pv, hi);
2123	>	}
2124	>	setTabAt(nextTab, i, lo);
2125	>	setTabAt(nextTab, i + bit, hi);
2126		}
2127
2128		/**
2129	<	* Gets the table entry for the given segment and hash code.
2130	<	*/
2131	<	@SuppressWarnings("unchecked")
2132	<	static final <K,V> HashEntry<K,V> entryForHash(Segment<K,V> seg, int h) {
2133	<	HashEntry<K,V>[] tab;
2134	<	return (seg == null || (tab = seg.table) == null) ? null :
2135	<	(HashEntry<K,V>) UNSAFE.getObjectVolatile
2136	<	(tab, ((long)(((tab.length - 1) & h)) << TSHIFT) + TBASE);
2129	>	* Splits a tree bin into lo and hi parts; installs in given table.
2130	>	*/
2131	>	private static void splitTreeBin(Node[] nextTab, int i, TreeBin t) {
2132	>	int bit = nextTab.length >>> 1;
2133	>	TreeBin lt = new TreeBin();
2134	>	TreeBin ht = new TreeBin();
2135	>	int lc = 0, hc = 0;
2136	>	for (Node e = t.first; e != null; e = e.next) {
2137	>	int h = e.hash & HASH_BITS;
2138	>	Object k = e.key, v = e.val;
2139	>	if ((h & bit) == 0) {
2140	>	++lc;
2141	>	lt.putTreeNode(h, k, v);
2142	>	}
2143	>	else {
2144	>	++hc;
2145	>	ht.putTreeNode(h, k, v);
2146	>	}
2147	>	}
2148	>	Node ln, hn; // throw away trees if too small
2149	>	if (lc <= (TREE_THRESHOLD >>> 1)) {
2150	>	ln = null;
2151	>	for (Node p = lt.first; p != null; p = p.next)
2152	>	ln = new Node(p.hash, p.key, p.val, ln);
2153	>	}
2154	>	else
2155	>	ln = new Node(MOVED, lt, null, null);
2156	>	setTabAt(nextTab, i, ln);
2157	>	if (hc <= (TREE_THRESHOLD >>> 1)) {
2158	>	hn = null;
2159	>	for (Node p = ht.first; p != null; p = p.next)
2160	>	hn = new Node(p.hash, p.key, p.val, hn);
2161	>	}
2162	>	else
2163	>	hn = new Node(MOVED, ht, null, null);
2164	>	setTabAt(nextTab, i + bit, hn);
2165		}
2166
2167	<	/* ---------------- Public operations -------------- */
2167	>	/**
2168	>	* Implementation for clear. Steps through each bin, removing all
2169	>	* nodes.
2170	>	*/
2171	>	private final void internalClear() {
2172	>	long delta = 0L; // negative number of deletions
2173	>	int i = 0;
2174	>	Node[] tab = table;
2175	>	while (tab != null && i < tab.length) {
2176	>	int fh; Object fk;
2177	>	Node f = tabAt(tab, i);
2178	>	if (f == null)
2179	>	++i;
2180	>	else if ((fh = f.hash) == MOVED) {
2181	>	if ((fk = f.key) instanceof TreeBin) {
2182	>	TreeBin t = (TreeBin)fk;
2183	>	t.acquire(0);
2184	>	try {
2185	>	if (tabAt(tab, i) == f) {
2186	>	for (Node p = t.first; p != null; p = p.next) {
2187	>	p.val = null;
2188	>	--delta;
2189	>	}
2190	>	t.first = null;
2191	>	t.root = null;
2192	>	++i;
2193	>	}
2194	>	} finally {
2195	>	t.release(0);
2196	>	}
2197	>	}
2198	>	else
2199	>	tab = (Node[])fk;
2200	>	}
2201	>	else if ((fh & LOCKED) != 0) {
2202	>	counter.add(delta); // opportunistically update count
2203	>	delta = 0L;
2204	>	f.tryAwaitLock(tab, i);
2205	>	}
2206	>	else if (f.casHash(fh, fh | LOCKED)) {
2207	>	try {
2208	>	if (tabAt(tab, i) == f) {
2209	>	for (Node e = f; e != null; e = e.next) {
2210	>	e.val = null;
2211	>	--delta;
2212	>	}
2213	>	setTabAt(tab, i, null);
2214	>	++i;
2215	>	}
2216	>	} finally {
2217	>	if (!f.casHash(fh | LOCKED, fh)) {
2218	>	f.hash = fh;
2219	>	synchronized (f) { f.notifyAll(); };
2220	>	}
2221	>	}
2222	>	}
2223	>	}
2224	>	if (delta != 0)
2225	>	counter.add(delta);
2226	>	}
2227	>
2228	>	/* ----------------Table Traversal -------------- */
2229
2230		/**
2231	<	* Creates a new, empty map with the specified initial
2232	<	* capacity, load factor and concurrency level.
2231	>	* Encapsulates traversal for methods such as containsValue; also
2232	>	* serves as a base class for other iterators and bulk tasks.
2233		*
2234	<	* @param initialCapacity the initial capacity. The implementation
2235	<	* performs internal sizing to accommodate this many elements.
2236	<	* @param loadFactor  the load factor threshold, used to control resizing.
2237	<	* Resizing may be performed when the average number of elements per
2238	<	* bin exceeds this threshold.
2239	<	* @param concurrencyLevel the estimated number of concurrently
2240	<	* updating threads. The implementation performs internal sizing
2241	<	* to try to accommodate this many threads.
2242	<	* @throws IllegalArgumentException if the initial capacity is
2243	<	* negative or the load factor or concurrencyLevel are
2244	<	* nonpositive.
2234	>	* At each step, the iterator snapshots the key ("nextKey") and
2235	>	* value ("nextVal") of a valid node (i.e., one that, at point of
2236	>	* snapshot, has a non-null user value). Because val fields can
2237	>	* change (including to null, indicating deletion), field nextVal
2238	>	* might not be accurate at point of use, but still maintains the
2239	>	* weak consistency property of holding a value that was once
2240	>	* valid.
2241	>	*
2242	>	* Internal traversals directly access these fields, as in:
2243	>	* {@code while (it.advance() != null) { process(it.nextKey); }}
2244	>	*
2245	>	* Exported iterators must track whether the iterator has advanced
2246	>	* (in hasNext vs next) (by setting/checking/nulling field
2247	>	* nextVal), and then extract key, value, or key-value pairs as
2248	>	* return values of next().
2249	>	*
2250	>	* The iterator visits once each still-valid node that was
2251	>	* reachable upon iterator construction. It might miss some that
2252	>	* were added to a bin after the bin was visited, which is OK wrt
2253	>	* consistency guarantees. Maintaining this property in the face
2254	>	* of possible ongoing resizes requires a fair amount of
2255	>	* bookkeeping state that is difficult to optimize away amidst
2256	>	* volatile accesses.  Even so, traversal maintains reasonable
2257	>	* throughput.
2258	>	*
2259	>	* Normally, iteration proceeds bin-by-bin traversing lists.
2260	>	* However, if the table has been resized, then all future steps
2261	>	* must traverse both the bin at the current index as well as at
2262	>	* (index + baseSize); and so on for further resizings. To
2263	>	* paranoically cope with potential sharing by users of iterators
2264	>	* across threads, iteration terminates if a bounds checks fails
2265	>	* for a table read.
2266	>	*
2267	>	* This class extends ForkJoinTask to streamline parallel
2268	>	* iteration in bulk operations (see BulkTask). This adds only an
2269	>	* int of space overhead, which is close enough to negligible in
2270	>	* cases where it is not needed to not worry about it.  Because
2271	>	* ForkJoinTask is Serializable, but iterators need not be, we
2272	>	* need to add warning suppressions.
2273	>	*/
2274	>	@SuppressWarnings("serial")
2275	>	static class Traverser<K,V,R> extends ForkJoinTask<R> {
2276	>	final ConcurrentHashMap<K, V> map;
2277	>	Node next;           // the next entry to use
2278	>	Node last;           // the last entry used
2279	>	Object nextKey;      // cached key field of next
2280	>	Object nextVal;      // cached val field of next
2281	>	Node[] tab;          // current table; updated if resized
2282	>	int index;           // index of bin to use next
2283	>	int baseIndex;       // current index of initial table
2284	>	int baseLimit;       // index bound for initial table
2285	>	final int baseSize;  // initial table size
2286	>
2287	>	/** Creates iterator for all entries in the table. */
2288	>	Traverser(ConcurrentHashMap<K, V> map) {
2289	>	this.tab = (this.map = map).table;
2290	>	baseLimit = baseSize = (tab == null) ? 0 : tab.length;
2291	>	}
2292	>
2293	>	/** Creates iterator for split() methods */
2294	>	Traverser(Traverser<K,V,?> it, boolean split) {
2295	>	this.map = it.map;
2296	>	this.tab = it.tab;
2297	>	this.baseSize = it.baseSize;
2298	>	int lo = it.baseIndex;
2299	>	int hi = this.baseLimit = it.baseLimit;
2300	>	int i;
2301	>	if (split) // adjust parent
2302	>	i = it.baseLimit = (lo + hi + 1) >>> 1;
2303	>	else       // clone parent
2304	>	i = lo;
2305	>	this.index = this.baseIndex = i;
2306	>	}
2307	>
2308	>	/**
2309	>	* Advances next; returns nextVal or null if terminated.
2310	>	* See above for explanation.
2311	>	*/
2312	>	final Object advance() {
2313	>	Node e = last = next;
2314	>	Object ev = null;
2315	>	outer: do {
2316	>	if (e != null)                  // advance past used/skipped node
2317	>	e = e.next;
2318	>	while (e == null) {             // get to next non-null bin
2319	>	Node[] t; int b, i, n; Object ek; // checks must use locals
2320	>	if ((b = baseIndex) >= baseLimit || (i = index) < 0 ||
2321	>	(t = tab) == null || i >= (n = t.length))
2322	>	break outer;
2323	>	else if ((e = tabAt(t, i)) != null && e.hash == MOVED) {
2324	>	if ((ek = e.key) instanceof TreeBin)
2325	>	e = ((TreeBin)ek).first;
2326	>	else {
2327	>	tab = (Node[])ek;
2328	>	continue;           // restarts due to null val
2329	>	}
2330	>	}                           // visit upper slots if present
2331	>	index = (i += baseSize) < n ? i : (baseIndex = b + 1);
2332	>	}
2333	>	nextKey = e.key;
2334	>	} while ((ev = e.val) == null);    // skip deleted or special nodes
2335	>	next = e;
2336	>	return nextVal = ev;
2337	>	}
2338	>
2339	>	public final void remove() {
2340	>	if (nextVal == null && last == null)
2341	>	advance();
2342	>	Node e = last;
2343	>	if (e == null)
2344	>	throw new IllegalStateException();
2345	>	last = null;
2346	>	map.remove(e.key);
2347	>	}
2348	>
2349	>	public final boolean hasNext() {
2350	>	return nextVal != null || advance() != null;
2351	>	}
2352	>
2353	>	public final boolean hasMoreElements() { return hasNext(); }
2354	>	public final void setRawResult(Object x) { }
2355	>	public R getRawResult() { return null; }
2356	>	public boolean exec() { return true; }
2357	>	}
2358	>
2359	>	/* ---------------- Public operations -------------- */
2360	>
2361	>	/**
2362	>	* Creates a new, empty map with the default initial table size (16).
2363		*/
2364	<	@SuppressWarnings("unchecked")
2365	<	public ConcurrentHashMap(int initialCapacity,
707	<	float loadFactor, int concurrencyLevel) {
708	<	if (!(loadFactor > 0) || initialCapacity < 0 || concurrencyLevel <= 0)
709	<	throw new IllegalArgumentException();
710	<	if (concurrencyLevel > MAX_SEGMENTS)
711	<	concurrencyLevel = MAX_SEGMENTS;
712	<	// Find power-of-two sizes best matching arguments
713	<	int sshift = 0;
714	<	int ssize = 1;
715	<	while (ssize < concurrencyLevel) {
716	<	++sshift;
717	<	ssize <<= 1;
718	<	}
719	<	this.segmentShift = 32 - sshift;
720	<	this.segmentMask = ssize - 1;
721	<	if (initialCapacity > MAXIMUM_CAPACITY)
722	<	initialCapacity = MAXIMUM_CAPACITY;
723	<	int c = initialCapacity / ssize;
724	<	if (c * ssize < initialCapacity)
725	<	++c;
726	<	int cap = MIN_SEGMENT_TABLE_CAPACITY;
727	<	while (cap < c)
728	<	cap <<= 1;
729	<	// create segments and segments[0]
730	<	Segment<K,V> s0 =
731	<	new Segment<K,V>(loadFactor, (int)(cap * loadFactor),
732	<	(HashEntry<K,V>[])new HashEntry<?,?>[cap]);
733	<	Segment<K,V>[] ss = (Segment<K,V>[])new Segment<?,?>[ssize];
734	<	UNSAFE.putOrderedObject(ss, SBASE, s0); // ordered write of segments[0]
735	<	this.segments = ss;
2364	>	public ConcurrentHashMap() {
2365	>	this.counter = new LongAdder();
2366		}
2367
2368		/**
2369	<	* Creates a new, empty map with the specified initial capacity
2370	<	* and load factor and with the default concurrencyLevel (16).
2369	>	* Creates a new, empty map with an initial table size
2370	>	* accommodating the specified number of elements without the need
2371	>	* to dynamically resize.
2372		*
2373		* @param initialCapacity The implementation performs internal
2374		* sizing to accommodate this many elements.
744	–	* @param loadFactor  the load factor threshold, used to control resizing.
745	–	* Resizing may be performed when the average number of elements per
746	–	* bin exceeds this threshold.
2375		* @throws IllegalArgumentException if the initial capacity of
2376	<	* elements is negative or the load factor is nonpositive
749	<	*
750	<	* @since 1.6
2376	>	* elements is negative
2377		*/
2378	<	public ConcurrentHashMap(int initialCapacity, float loadFactor) {
2379	<	this(initialCapacity, loadFactor, DEFAULT_CONCURRENCY_LEVEL);
2378	>	public ConcurrentHashMap(int initialCapacity) {
2379	>	if (initialCapacity < 0)
2380	>	throw new IllegalArgumentException();
2381	>	int cap = ((initialCapacity >= (MAXIMUM_CAPACITY >>> 1)) ?
2382	>	MAXIMUM_CAPACITY :
2383	>	tableSizeFor(initialCapacity + (initialCapacity >>> 1) + 1));
2384	>	this.counter = new LongAdder();
2385	>	this.sizeCtl = cap;
2386		}
2387
2388		/**
2389	<	* Creates a new, empty map with the specified initial capacity,
758	<	* and with default load factor (0.75) and concurrencyLevel (16).
2389	>	* Creates a new map with the same mappings as the given map.
2390		*
2391	<	* @param initialCapacity the initial capacity. The implementation
761	<	* performs internal sizing to accommodate this many elements.
762	<	* @throws IllegalArgumentException if the initial capacity of
763	<	* elements is negative.
2391	>	* @param m the map
2392		*/
2393	<	public ConcurrentHashMap(int initialCapacity) {
2394	<	this(initialCapacity, DEFAULT_LOAD_FACTOR, DEFAULT_CONCURRENCY_LEVEL);
2393	>	public ConcurrentHashMap(Map<? extends K, ? extends V> m) {
2394	>	this.counter = new LongAdder();
2395	>	this.sizeCtl = DEFAULT_CAPACITY;
2396	>	internalPutAll(m);
2397		}
2398
2399		/**
2400	<	* Creates a new, empty map with a default initial capacity (16),
2401	<	* load factor (0.75) and concurrencyLevel (16).
2400	>	* Creates a new, empty map with an initial table size based on
2401	>	* the given number of elements ({@code initialCapacity}) and
2402	>	* initial table density ({@code loadFactor}).
2403	>	*
2404	>	* @param initialCapacity the initial capacity. The implementation
2405	>	* performs internal sizing to accommodate this many elements,
2406	>	* given the specified load factor.
2407	>	* @param loadFactor the load factor (table density) for
2408	>	* establishing the initial table size
2409	>	* @throws IllegalArgumentException if the initial capacity of
2410	>	* elements is negative or the load factor is nonpositive
2411	>	*
2412	>	* @since 1.6
2413		*/
2414	<	public ConcurrentHashMap() {
2415	<	this(DEFAULT_INITIAL_CAPACITY, DEFAULT_LOAD_FACTOR, DEFAULT_CONCURRENCY_LEVEL);
2414	>	public ConcurrentHashMap(int initialCapacity, float loadFactor) {
2415	>	this(initialCapacity, loadFactor, 1);
2416		}
2417
2418		/**
2419	<	* Creates a new map with the same mappings as the given map.
2420	<	* The map is created with a capacity of 1.5 times the number
2421	<	* of mappings in the given map or 16 (whichever is greater),
2422	<	* and a default load factor (0.75) and concurrencyLevel (16).
2419	>	* Creates a new, empty map with an initial table size based on
2420	>	* the given number of elements ({@code initialCapacity}), table
2421	>	* density ({@code loadFactor}), and number of concurrently
2422	>	* updating threads ({@code concurrencyLevel}).
2423		*
2424	<	* @param m the map
2424	>	* @param initialCapacity the initial capacity. The implementation
2425	>	* performs internal sizing to accommodate this many elements,
2426	>	* given the specified load factor.
2427	>	* @param loadFactor the load factor (table density) for
2428	>	* establishing the initial table size
2429	>	* @param concurrencyLevel the estimated number of concurrently
2430	>	* updating threads. The implementation may use this value as
2431	>	* a sizing hint.
2432	>	* @throws IllegalArgumentException if the initial capacity is
2433	>	* negative or the load factor or concurrencyLevel are
2434	>	* nonpositive
2435		*/
2436	<	public ConcurrentHashMap(Map<? extends K, ? extends V> m) {
2437	<	this(Math.max((int) (m.size() / DEFAULT_LOAD_FACTOR) + 1,
2438	<	DEFAULT_INITIAL_CAPACITY),
2439	<	DEFAULT_LOAD_FACTOR, DEFAULT_CONCURRENCY_LEVEL);
2440	<	putAll(m);
2436	>	public ConcurrentHashMap(int initialCapacity,
2437	>	float loadFactor, int concurrencyLevel) {
2438	>	if (!(loadFactor > 0.0f) || initialCapacity < 0 || concurrencyLevel <= 0)
2439	>	throw new IllegalArgumentException();
2440	>	if (initialCapacity < concurrencyLevel)   // Use at least as many bins
2441	>	initialCapacity = concurrencyLevel;   // as estimated threads
2442	>	long size = (long)(1.0 + (long)initialCapacity / loadFactor);
2443	>	int cap = (size >= (long)MAXIMUM_CAPACITY) ?
2444	>	MAXIMUM_CAPACITY : tableSizeFor((int)size);
2445	>	this.counter = new LongAdder();
2446	>	this.sizeCtl = cap;
2447		}
2448
2449		/**
2450	<	* Returns <tt>true</tt> if this map contains no key-value mappings.
794	<	*
795	<	* @return <tt>true</tt> if this map contains no key-value mappings
2450	>	* {@inheritDoc}
2451		*/
2452		public boolean isEmpty() {
2453	<	/*
799	<	* Sum per-segment modCounts to avoid mis-reporting when
800	<	* elements are concurrently added and removed in one segment
801	<	* while checking another, in which case the table was never
802	<	* actually empty at any point. (The sum ensures accuracy up
803	<	* through at least 1<<31 per-segment modifications before
804	<	* recheck.)  Methods size() and containsValue() use similar
805	<	* constructions for stability checks.
806	<	*/
807	<	long sum = 0L;
808	<	final Segment<K,V>[] segments = this.segments;
809	<	for (int j = 0; j < segments.length; ++j) {
810	<	Segment<K,V> seg = segmentAt(segments, j);
811	<	if (seg != null) {
812	<	if (seg.count != 0)
813	<	return false;
814	<	sum += seg.modCount;
815	<	}
816	<	}
817	<	if (sum != 0L) { // recheck unless no modifications
818	<	for (int j = 0; j < segments.length; ++j) {
819	<	Segment<K,V> seg = segmentAt(segments, j);
820	<	if (seg != null) {
821	<	if (seg.count != 0)
822	<	return false;
823	<	sum -= seg.modCount;
824	<	}
825	<	}
826	<	if (sum != 0L)
827	<	return false;
828	<	}
829	<	return true;
2453	>	return counter.sum() <= 0L; // ignore transient negative values
2454		}
2455
2456		/**
2457	<	* Returns the number of key-value mappings in this map.  If the
834	<	* map contains more than <tt>Integer.MAX_VALUE</tt> elements, returns
835	<	* <tt>Integer.MAX_VALUE</tt>.
836	<	*
837	<	* @return the number of key-value mappings in this map
2457	>	* {@inheritDoc}
2458		*/
2459		public int size() {
2460	<	// Try a few times to get accurate count. On failure due to
2461	<	// continuous async changes in table, resort to locking.
2462	<	final Segment<K,V>[] segments = this.segments;
2463	<	final int segmentCount = segments.length;
2464	<
845	<	long previousSum = 0L;
846	<	for (int retries = -1; retries < RETRIES_BEFORE_LOCK; retries++) {
847	<	long sum = 0L;    // sum of modCounts
848	<	long size = 0L;
849	<	for (int i = 0; i < segmentCount; i++) {
850	<	Segment<K,V> segment = segmentAt(segments, i);
851	<	if (segment != null) {
852	<	sum += segment.modCount;
853	<	size += segment.count;
854	<	}
855	<	}
856	<	if (sum == previousSum)
857	<	return ((size >>> 31) == 0) ? (int) size : Integer.MAX_VALUE;
858	<	previousSum = sum;
859	<	}
2460	>	long n = counter.sum();
2461	>	return ((n < 0L) ? 0 :
2462	>	(n > (long)Integer.MAX_VALUE) ? Integer.MAX_VALUE :
2463	>	(int)n);
2464	>	}
2465
2466	<	long size = 0L;
2467	<	for (int i = 0; i < segmentCount; i++) {
2468	<	Segment<K,V> segment = ensureSegment(i);
2469	<	segment.lock();
2470	<	size += segment.count;
2471	<	}
2472	<	for (int i = 0; i < segmentCount; i++)
2473	<	segments[i].unlock();
2474	<	return ((size >>> 31) == 0) ? (int) size : Integer.MAX_VALUE;
2466	>	/**
2467	>	* Returns the number of mappings. This method should be used
2468	>	* instead of {@link #size} because a ConcurrentHashMap may
2469	>	* contain more mappings than can be represented as an int. The
2470	>	* value returned is a snapshot; the actual count may differ if
2471	>	* there are ongoing concurrent insertions of removals.
2472	>	*
2473	>	* @return the number of mappings
2474	>	*/
2475	>	public long mappingCount() {
2476	>	long n = counter.sum();
2477	>	return (n < 0L) ? 0L : n; // ignore transient negative values
2478		}
2479
2480		/**
#	Line 880 | Line 2488 | public class ConcurrentHashMap<K, V> ext
2488		*
2489		* @throws NullPointerException if the specified key is null
2490		*/
2491	+	@SuppressWarnings("unchecked")
2492		public V get(Object key) {
2493	<	Segment<K,V> s; // manually integrate access methods to reduce overhead
2494	<	HashEntry<K,V>[] tab;
2495	<	int h = hash(key.hashCode());
887	<	long u = (((h >>> segmentShift) & segmentMask) << SSHIFT) + SBASE;
888	<	if ((s = (Segment<K,V>)UNSAFE.getObjectVolatile(segments, u)) != null &&
889	<	(tab = s.table) != null) {
890	<	for (HashEntry<K,V> e = (HashEntry<K,V>) UNSAFE.getObjectVolatile
891	<	(tab, ((long)(((tab.length - 1) & h)) << TSHIFT) + TBASE);
892	<	e != null; e = e.next) {
893	<	K k;
894	<	if ((k = e.key) == key || (e.hash == h && key.equals(k)))
895	<	return e.value;
896	<	}
897	<	}
898	<	return null;
2493	>	if (key == null)
2494	>	throw new NullPointerException();
2495	>	return (V)internalGet(key);
2496		}
2497
2498		/**
2499		* Tests if the specified object is a key in this table.
2500		*
2501		* @param  key   possible key
2502	<	* @return <tt>true</tt> if and only if the specified object
2502	>	* @return {@code true} if and only if the specified object
2503		*         is a key in this table, as determined by the
2504	<	*         <tt>equals</tt> method; <tt>false</tt> otherwise.
2504	>	*         {@code equals} method; {@code false} otherwise
2505		* @throws NullPointerException if the specified key is null
2506		*/
910	–	@SuppressWarnings("unchecked")
2507		public boolean containsKey(Object key) {
2508	<	Segment<K,V> s; // same as get() except no need for volatile value read
2509	<	HashEntry<K,V>[] tab;
2510	<	int h = hash(key.hashCode());
915	<	long u = (((h >>> segmentShift) & segmentMask) << SSHIFT) + SBASE;
916	<	if ((s = (Segment<K,V>)UNSAFE.getObjectVolatile(segments, u)) != null &&
917	<	(tab = s.table) != null) {
918	<	for (HashEntry<K,V> e = (HashEntry<K,V>) UNSAFE.getObjectVolatile
919	<	(tab, ((long)(((tab.length - 1) & h)) << TSHIFT) + TBASE);
920	<	e != null; e = e.next) {
921	<	K k;
922	<	if ((k = e.key) == key || (e.hash == h && key.equals(k)))
923	<	return true;
924	<	}
925	<	}
926	<	return false;
2508	>	if (key == null)
2509	>	throw new NullPointerException();
2510	>	return internalGet(key) != null;
2511		}
2512
2513		/**
2514	<	* Returns <tt>true</tt> if this map maps one or more keys to the
2515	<	* specified value. Note: This method requires a full internal
2516	<	* traversal of the hash table, and so is much slower than
933	<	* method <tt>containsKey</tt>.
2514	>	* Returns {@code true} if this map maps one or more keys to the
2515	>	* specified value. Note: This method may require a full traversal
2516	>	* of the map, and is much slower than method {@code containsKey}.
2517		*
2518		* @param value value whose presence in this map is to be tested
2519	<	* @return <tt>true</tt> if this map maps one or more keys to the
2519	>	* @return {@code true} if this map maps one or more keys to the
2520		*         specified value
2521		* @throws NullPointerException if the specified value is null
2522		*/
2523		public boolean containsValue(Object value) {
941	–	// Same idea as size()
2524		if (value == null)
2525		throw new NullPointerException();
2526	<	final Segment<K,V>[] segments = this.segments;
2527	<	long previousSum = 0L;
2528	<	int lockCount = 0;
2529	<	try {
2530	<	for (int retries = -1; ; retries++) {
949	<	long sum = 0L;    // sum of modCounts
950	<	for (int j = 0; j < segments.length; j++) {
951	<	Segment<K,V> segment;
952	<	if (retries == RETRIES_BEFORE_LOCK) {
953	<	segment = ensureSegment(j);
954	<	segment.lock();
955	<	lockCount++;
956	<	} else {
957	<	segment = segmentAt(segments, j);
958	<	if (segment == null)
959	<	continue;
960	<	}
961	<	HashEntry<K,V>[] tab = segment.table;
962	<	if (tab != null) {
963	<	for (int i = 0 ; i < tab.length; i++) {
964	<	HashEntry<K,V> e;
965	<	for (e = entryAt(tab, i); e != null; e = e.next) {
966	<	V v = e.value;
967	<	if (v != null && value.equals(v))
968	<	return true;
969	<	}
970	<	}
971	<	sum += segment.modCount;
972	<	}
973	<	}
974	<	if ((retries >= 0 && sum == previousSum) || lockCount > 0)
975	<	return false;
976	<	previousSum = sum;
977	<	}
978	<	} finally {
979	<	for (int j = 0; j < lockCount; j++)
980	<	segments[j].unlock();
2526	>	Object v;
2527	>	Traverser<K,V,Object> it = new Traverser<K,V,Object>(this);
2528	>	while ((v = it.advance()) != null) {
2529	>	if (v == value || value.equals(v))
2530	>	return true;
2531		}
2532	+	return false;
2533		}
2534
2535		/**
#	Line 990 | Line 2541 | public class ConcurrentHashMap<K, V> ext
2541		* Java Collections framework.
2542		*
2543		* @param  value a value to search for
2544	<	* @return <tt>true</tt> if and only if some key maps to the
2545	<	*         <tt>value</tt> argument in this table as
2546	<	*         determined by the <tt>equals</tt> method;
2547	<	*         <tt>false</tt> otherwise
2544	>	* @return {@code true} if and only if some key maps to the
2545	>	*         {@code value} argument in this table as
2546	>	*         determined by the {@code equals} method;
2547	>	*         {@code false} otherwise
2548		* @throws NullPointerException if the specified value is null
2549		*/
2550		public boolean contains(Object value) {
#	Line 1004 | Line 2555 | public class ConcurrentHashMap<K, V> ext
2555		* Maps the specified key to the specified value in this table.
2556		* Neither the key nor the value can be null.
2557		*
2558	<	* <p> The value can be retrieved by calling the <tt>get</tt> method
2558	>	* <p> The value can be retrieved by calling the {@code get} method
2559		* with a key that is equal to the original key.
2560		*
2561		* @param key key with which the specified value is to be associated
2562		* @param value value to be associated with the specified key
2563	<	* @return the previous value associated with <tt>key</tt>, or
2564	<	*         <tt>null</tt> if there was no mapping for <tt>key</tt>
2563	>	* @return the previous value associated with {@code key}, or
2564	>	*         {@code null} if there was no mapping for {@code key}
2565		* @throws NullPointerException if the specified key or value is null
2566		*/
2567		@SuppressWarnings("unchecked")
2568		public V put(K key, V value) {
2569	<	Segment<K,V> s;
1019	<	if (value == null)
2569	>	if (key == null || value == null)
2570		throw new NullPointerException();
2571	<	int hash = hash(key.hashCode());
1022	<	int j = (hash >>> segmentShift) & segmentMask;
1023	<	if ((s = (Segment<K,V>)UNSAFE.getObject          // nonvolatile; recheck
1024	<	(segments, (j << SSHIFT) + SBASE)) == null) //  in ensureSegment
1025	<	s = ensureSegment(j);
1026	<	return s.put(key, hash, value, false);
2571	>	return (V)internalPut(key, value);
2572		}
2573
2574		/**
2575		* {@inheritDoc}
2576		*
2577		* @return the previous value associated with the specified key,
2578	<	*         or <tt>null</tt> if there was no mapping for the key
2578	>	*         or {@code null} if there was no mapping for the key
2579		* @throws NullPointerException if the specified key or value is null
2580		*/
2581		@SuppressWarnings("unchecked")
2582		public V putIfAbsent(K key, V value) {
2583	<	Segment<K,V> s;
1039	<	if (value == null)
2583	>	if (key == null || value == null)
2584		throw new NullPointerException();
2585	<	int hash = hash(key.hashCode());
1042	<	int j = (hash >>> segmentShift) & segmentMask;
1043	<	if ((s = (Segment<K,V>)UNSAFE.getObject
1044	<	(segments, (j << SSHIFT) + SBASE)) == null)
1045	<	s = ensureSegment(j);
1046	<	return s.put(key, hash, value, true);
2585	>	return (V)internalPutIfAbsent(key, value);
2586		}
2587
2588		/**
#	Line 1054 | Line 2593 | public class ConcurrentHashMap<K, V> ext
2593		* @param m mappings to be stored in this map
2594		*/
2595		public void putAll(Map<? extends K, ? extends V> m) {
2596	<	for (Map.Entry<? extends K, ? extends V> e : m.entrySet())
2597	<	put(e.getKey(), e.getValue());
2596	>	internalPutAll(m);
2597	>	}
2598	>
2599	>	/**
2600	>	* If the specified key is not already associated with a value,
2601	>	* computes its value using the given mappingFunction and enters
2602	>	* it into the map unless null.  This is equivalent to
2603	>	* <pre> {@code
2604	>	* if (map.containsKey(key))
2605	>	*   return map.get(key);
2606	>	* value = mappingFunction.apply(key);
2607	>	* if (value != null)
2608	>	*   map.put(key, value);
2609	>	* return value;}</pre>
2610	>	*
2611	>	* except that the action is performed atomically.  If the
2612	>	* function returns {@code null} no mapping is recorded. If the
2613	>	* function itself throws an (unchecked) exception, the exception
2614	>	* is rethrown to its caller, and no mapping is recorded.  Some
2615	>	* attempted update operations on this map by other threads may be
2616	>	* blocked while computation is in progress, so the computation
2617	>	* should be short and simple, and must not attempt to update any
2618	>	* other mappings of this Map. The most appropriate usage is to
2619	>	* construct a new object serving as an initial mapped value, or
2620	>	* memoized result, as in:
2621	>	*
2622	>	*  <pre> {@code
2623	>	* map.computeIfAbsent(key, new Fun<K, V>() {
2624	>	*   public V map(K k) { return new Value(f(k)); }});}</pre>
2625	>	*
2626	>	* @param key key with which the specified value is to be associated
2627	>	* @param mappingFunction the function to compute a value
2628	>	* @return the current (existing or computed) value associated with
2629	>	*         the specified key, or null if the computed value is null.
2630	>	* @throws NullPointerException if the specified key or mappingFunction
2631	>	*         is null
2632	>	* @throws IllegalStateException if the computation detectably
2633	>	*         attempts a recursive update to this map that would
2634	>	*         otherwise never complete
2635	>	* @throws RuntimeException or Error if the mappingFunction does so,
2636	>	*         in which case the mapping is left unestablished
2637	>	*/
2638	>	@SuppressWarnings("unchecked")
2639	>	public V computeIfAbsent(K key, Fun<? super K, ? extends V> mappingFunction) {
2640	>	if (key == null || mappingFunction == null)
2641	>	throw new NullPointerException();
2642	>	return (V)internalComputeIfAbsent(key, mappingFunction);
2643	>	}
2644	>
2645	>	/**
2646	>	* If the given key is present, computes a new mapping value given a key and
2647	>	* its current mapped value. This is equivalent to
2648	>	*  <pre> {@code
2649	>	*   if (map.containsKey(key)) {
2650	>	*     value = remappingFunction.apply(key, map.get(key));
2651	>	*     if (value != null)
2652	>	*       map.put(key, value);
2653	>	*     else
2654	>	*       map.remove(key);
2655	>	*   }
2656	>	* }</pre>
2657	>	*
2658	>	* except that the action is performed atomically.  If the
2659	>	* function returns {@code null}, the mapping is removed.  If the
2660	>	* function itself throws an (unchecked) exception, the exception
2661	>	* is rethrown to its caller, and the current mapping is left
2662	>	* unchanged.  Some attempted update operations on this map by
2663	>	* other threads may be blocked while computation is in progress,
2664	>	* so the computation should be short and simple, and must not
2665	>	* attempt to update any other mappings of this Map. For example,
2666	>	* to either create or append new messages to a value mapping:
2667	>	*
2668	>	* @param key key with which the specified value is to be associated
2669	>	* @param remappingFunction the function to compute a value
2670	>	* @return the new value associated with the specified key, or null if none
2671	>	* @throws NullPointerException if the specified key or remappingFunction
2672	>	*         is null
2673	>	* @throws IllegalStateException if the computation detectably
2674	>	*         attempts a recursive update to this map that would
2675	>	*         otherwise never complete
2676	>	* @throws RuntimeException or Error if the remappingFunction does so,
2677	>	*         in which case the mapping is unchanged
2678	>	*/
2679	>	@SuppressWarnings("unchecked")
2680	>	public V computeIfPresent(K key, BiFun<? super K, ? super V, ? extends V> remappingFunction) {
2681	>	if (key == null || remappingFunction == null)
2682	>	throw new NullPointerException();
2683	>	return (V)internalCompute(key, true, remappingFunction);
2684	>	}
2685	>
2686	>	/**
2687	>	* Computes a new mapping value given a key and
2688	>	* its current mapped value (or {@code null} if there is no current
2689	>	* mapping). This is equivalent to
2690	>	*  <pre> {@code
2691	>	*   value = remappingFunction.apply(key, map.get(key));
2692	>	*   if (value != null)
2693	>	*     map.put(key, value);
2694	>	*   else
2695	>	*     map.remove(key);
2696	>	* }</pre>
2697	>	*
2698	>	* except that the action is performed atomically.  If the
2699	>	* function returns {@code null}, the mapping is removed.  If the
2700	>	* function itself throws an (unchecked) exception, the exception
2701	>	* is rethrown to its caller, and the current mapping is left
2702	>	* unchanged.  Some attempted update operations on this map by
2703	>	* other threads may be blocked while computation is in progress,
2704	>	* so the computation should be short and simple, and must not
2705	>	* attempt to update any other mappings of this Map. For example,
2706	>	* to either create or append new messages to a value mapping:
2707	>	*
2708	>	* <pre> {@code
2709	>	* Map<Key, String> map = ...;
2710	>	* final String msg = ...;
2711	>	* map.compute(key, new BiFun<Key, String, String>() {
2712	>	*   public String apply(Key k, String v) {
2713	>	*    return (v == null) ? msg : v + msg;});}}</pre>
2714	>	*
2715	>	* @param key key with which the specified value is to be associated
2716	>	* @param remappingFunction the function to compute a value
2717	>	* @return the new value associated with the specified key, or null if none
2718	>	* @throws NullPointerException if the specified key or remappingFunction
2719	>	*         is null
2720	>	* @throws IllegalStateException if the computation detectably
2721	>	*         attempts a recursive update to this map that would
2722	>	*         otherwise never complete
2723	>	* @throws RuntimeException or Error if the remappingFunction does so,
2724	>	*         in which case the mapping is unchanged
2725	>	*/
2726	>	@SuppressWarnings("unchecked")
2727	>	public V compute(K key, BiFun<? super K, ? super V, ? extends V> remappingFunction) {
2728	>	if (key == null || remappingFunction == null)
2729	>	throw new NullPointerException();
2730	>	return (V)internalCompute(key, false, remappingFunction);
2731	>	}
2732	>
2733	>	/**
2734	>	* If the specified key is not already associated
2735	>	* with a value, associate it with the given value.
2736	>	* Otherwise, replace the value with the results of
2737	>	* the given remapping function. This is equivalent to:
2738	>	*  <pre> {@code
2739	>	*   if (!map.containsKey(key))
2740	>	*     map.put(value);
2741	>	*   else {
2742	>	*     newValue = remappingFunction.apply(map.get(key), value);
2743	>	*     if (value != null)
2744	>	*       map.put(key, value);
2745	>	*     else
2746	>	*       map.remove(key);
2747	>	*   }
2748	>	* }</pre>
2749	>	* except that the action is performed atomically.  If the
2750	>	* function returns {@code null}, the mapping is removed.  If the
2751	>	* function itself throws an (unchecked) exception, the exception
2752	>	* is rethrown to its caller, and the current mapping is left
2753	>	* unchanged.  Some attempted update operations on this map by
2754	>	* other threads may be blocked while computation is in progress,
2755	>	* so the computation should be short and simple, and must not
2756	>	* attempt to update any other mappings of this Map.
2757	>	*/
2758	>	@SuppressWarnings("unchecked")
2759	>	public V merge(K key, V value, BiFun<? super V, ? super V, ? extends V> remappingFunction) {
2760	>	if (key == null || value == null || remappingFunction == null)
2761	>	throw new NullPointerException();
2762	>	return (V)internalMerge(key, value, remappingFunction);
2763		}
2764
2765		/**
#	Line 1063 | Line 2767 | public class ConcurrentHashMap<K, V> ext
2767		* This method does nothing if the key is not in the map.
2768		*
2769		* @param  key the key that needs to be removed
2770	<	* @return the previous value associated with <tt>key</tt>, or
2771	<	*         <tt>null</tt> if there was no mapping for <tt>key</tt>
2770	>	* @return the previous value associated with {@code key}, or
2771	>	*         {@code null} if there was no mapping for {@code key}
2772		* @throws NullPointerException if the specified key is null
2773		*/
2774	<	public V remove(Object key) {
2775	<	int hash = hash(key.hashCode());
2776	<	Segment<K,V> s = segmentForHash(hash);
2777	<	return s == null ? null : s.remove(key, hash, null);
2774	>	@SuppressWarnings("unchecked")
2775	>	public V remove(Object key) {
2776	>	if (key == null)
2777	>	throw new NullPointerException();
2778	>	return (V)internalReplace(key, null, null);
2779		}
2780
2781		/**
#	Line 1079 | Line 2784 | public class ConcurrentHashMap<K, V> ext
2784		* @throws NullPointerException if the specified key is null
2785		*/
2786		public boolean remove(Object key, Object value) {
2787	<	int hash = hash(key.hashCode());
2788	<	Segment<K,V> s;
2789	<	return value != null && (s = segmentForHash(hash)) != null &&
2790	<	s.remove(key, hash, value) != null;
2787	>	if (key == null)
2788	>	throw new NullPointerException();
2789	>	if (value == null)
2790	>	return false;
2791	>	return internalReplace(key, null, value) != null;
2792		}
2793
2794		/**
#	Line 1091 | Line 2797 | public class ConcurrentHashMap<K, V> ext
2797		* @throws NullPointerException if any of the arguments are null
2798		*/
2799		public boolean replace(K key, V oldValue, V newValue) {
2800	<	int hash = hash(key.hashCode());
1095	<	if (oldValue == null || newValue == null)
2800	>	if (key == null || oldValue == null || newValue == null)
2801		throw new NullPointerException();
2802	<	Segment<K,V> s = segmentForHash(hash);
1098	<	return s != null && s.replace(key, hash, oldValue, newValue);
2802	>	return internalReplace(key, newValue, oldValue) != null;
2803		}
2804
2805		/**
2806		* {@inheritDoc}
2807		*
2808		* @return the previous value associated with the specified key,
2809	<	*         or <tt>null</tt> if there was no mapping for the key
2809	>	*         or {@code null} if there was no mapping for the key
2810		* @throws NullPointerException if the specified key or value is null
2811		*/
2812	<	public V replace(K key, V value) {
2813	<	int hash = hash(key.hashCode());
2814	<	if (value == null)
2812	>	@SuppressWarnings("unchecked")
2813	>	public V replace(K key, V value) {
2814	>	if (key == null || value == null)
2815		throw new NullPointerException();
2816	<	Segment<K,V> s = segmentForHash(hash);
1113	<	return s == null ? null : s.replace(key, hash, value);
2816	>	return (V)internalReplace(key, value, null);
2817		}
2818
2819		/**
2820		* Removes all of the mappings from this map.
2821		*/
2822		public void clear() {
2823	<	final Segment<K,V>[] segments = this.segments;
1121	<	for (int j = 0; j < segments.length; ++j) {
1122	<	Segment<K,V> s = segmentAt(segments, j);
1123	<	if (s != null)
1124	<	s.clear();
1125	<	}
2823	>	internalClear();
2824		}
2825
2826		/**
#	Line 1130 | Line 2828 | public class ConcurrentHashMap<K, V> ext
2828		* The set is backed by the map, so changes to the map are
2829		* reflected in the set, and vice-versa.  The set supports element
2830		* removal, which removes the corresponding mapping from this map,
2831	<	* via the <tt>Iterator.remove</tt>, <tt>Set.remove</tt>,
2832	<	* <tt>removeAll</tt>, <tt>retainAll</tt>, and <tt>clear</tt>
2833	<	* operations.  It does not support the <tt>add</tt> or
2834	<	* <tt>addAll</tt> operations.
2831	>	* via the {@code Iterator.remove}, {@code Set.remove},
2832	>	* {@code removeAll}, {@code retainAll}, and {@code clear}
2833	>	* operations.  It does not support the {@code add} or
2834	>	* {@code addAll} operations.
2835		*
2836	<	* <p>The view's <tt>iterator</tt> is a "weakly consistent" iterator
2836	>	* <p>The view's {@code iterator} is a "weakly consistent" iterator
2837		* that will never throw {@link ConcurrentModificationException},
2838		* and guarantees to traverse elements as they existed upon
2839		* construction of the iterator, and may (but is not guaranteed to)
2840		* reflect any modifications subsequent to construction.
2841		*/
2842		public Set<K> keySet() {
2843	<	Set<K> ks = keySet;
2844	<	return (ks != null) ? ks : (keySet = new KeySet());
2843	>	KeySet<K,V> ks = keySet;
2844	>	return (ks != null) ? ks : (keySet = new KeySet<K,V>(this));
2845		}
2846
2847		/**
#	Line 1151 | Line 2849 | public class ConcurrentHashMap<K, V> ext
2849		* The collection is backed by the map, so changes to the map are
2850		* reflected in the collection, and vice-versa.  The collection
2851		* supports element removal, which removes the corresponding
2852	<	* mapping from this map, via the <tt>Iterator.remove</tt>,
2853	<	* <tt>Collection.remove</tt>, <tt>removeAll</tt>,
2854	<	* <tt>retainAll</tt>, and <tt>clear</tt> operations.  It does not
2855	<	* support the <tt>add</tt> or <tt>addAll</tt> operations.
2852	>	* mapping from this map, via the {@code Iterator.remove},
2853	>	* {@code Collection.remove}, {@code removeAll},
2854	>	* {@code retainAll}, and {@code clear} operations.  It does not
2855	>	* support the {@code add} or {@code addAll} operations.
2856		*
2857	<	* <p>The view's <tt>iterator</tt> is a "weakly consistent" iterator
2857	>	* <p>The view's {@code iterator} is a "weakly consistent" iterator
2858		* that will never throw {@link ConcurrentModificationException},
2859		* and guarantees to traverse elements as they existed upon
2860		* construction of the iterator, and may (but is not guaranteed to)
2861		* reflect any modifications subsequent to construction.
2862		*/
2863		public Collection<V> values() {
2864	<	Collection<V> vs = values;
2865	<	return (vs != null) ? vs : (values = new Values());
2864	>	Values<K,V> vs = values;
2865	>	return (vs != null) ? vs : (values = new Values<K,V>(this));
2866		}
2867
2868		/**
#	Line 1172 | Line 2870 | public class ConcurrentHashMap<K, V> ext
2870		* The set is backed by the map, so changes to the map are
2871		* reflected in the set, and vice-versa.  The set supports element
2872		* removal, which removes the corresponding mapping from the map,
2873	<	* via the <tt>Iterator.remove</tt>, <tt>Set.remove</tt>,
2874	<	* <tt>removeAll</tt>, <tt>retainAll</tt>, and <tt>clear</tt>
2875	<	* operations.  It does not support the <tt>add</tt> or
2876	<	* <tt>addAll</tt> operations.
2873	>	* via the {@code Iterator.remove}, {@code Set.remove},
2874	>	* {@code removeAll}, {@code retainAll}, and {@code clear}
2875	>	* operations.  It does not support the {@code add} or
2876	>	* {@code addAll} operations.
2877		*
2878	<	* <p>The view's <tt>iterator</tt> is a "weakly consistent" iterator
2878	>	* <p>The view's {@code iterator} is a "weakly consistent" iterator
2879		* that will never throw {@link ConcurrentModificationException},
2880		* and guarantees to traverse elements as they existed upon
2881		* construction of the iterator, and may (but is not guaranteed to)
2882		* reflect any modifications subsequent to construction.
2883		*/
2884		public Set<Map.Entry<K,V>> entrySet() {
2885	<	Set<Map.Entry<K,V>> es = entrySet;
2886	<	return (es != null) ? es : (entrySet = new EntrySet());
2885	>	EntrySet<K,V> es = entrySet;
2886	>	return (es != null) ? es : (entrySet = new EntrySet<K,V>(this));
2887		}
2888
2889		/**
#	Line 1195 | Line 2893 | public class ConcurrentHashMap<K, V> ext
2893		* @see #keySet()
2894		*/
2895		public Enumeration<K> keys() {
2896	<	return new KeyIterator();
2896	>	return new KeyIterator<K,V>(this);
2897		}
2898
2899		/**
#	Line 1205 | Line 2903 | public class ConcurrentHashMap<K, V> ext
2903		* @see #values()
2904		*/
2905		public Enumeration<V> elements() {
2906	<	return new ValueIterator();
2906	>	return new ValueIterator<K,V>(this);
2907		}
2908
2909	<	/* ---------------- Iterator Support -------------- */
2909	>	/**
2910	>	* Returns a partitionable iterator of the keys in this map.
2911	>	*
2912	>	* @return a partitionable iterator of the keys in this map
2913	>	*/
2914	>	public Spliterator<K> keySpliterator() {
2915	>	return new KeyIterator<K,V>(this);
2916	>	}
2917
2918	<	abstract class HashIterator {
2919	<	int nextSegmentIndex;
2920	<	int nextTableIndex;
2921	<	HashEntry<K,V>[] currentTable;
2922	<	HashEntry<K, V> nextEntry;
2923	<	HashEntry<K, V> lastReturned;
2918	>	/**
2919	>	* Returns a partitionable iterator of the values in this map.
2920	>	*
2921	>	* @return a partitionable iterator of the values in this map
2922	>	*/
2923	>	public Spliterator<V> valueSpliterator() {
2924	>	return new ValueIterator<K,V>(this);
2925	>	}
2926
2927	<	HashIterator() {
2928	<	nextSegmentIndex = segments.length - 1;
2929	<	nextTableIndex = -1;
2930	<	advance();
2931	<	}
2927	>	/**
2928	>	* Returns a partitionable iterator of the entries in this map.
2929	>	*
2930	>	* @return a partitionable iterator of the entries in this map
2931	>	*/
2932	>	public Spliterator<Map.Entry<K,V>> entrySpliterator() {
2933	>	return new EntryIterator<K,V>(this);
2934	>	}
2935
2936	<	/**
2937	<	* Sets nextEntry to first node of next non-empty table
2938	<	* (in backwards order, to simplify checks).
2939	<	*/
2940	<	final void advance() {
2936	>	/**
2937	>	* Returns the hash code value for this {@link Map}, i.e.,
2938	>	* the sum of, for each key-value pair in the map,
2939	>	* {@code key.hashCode() ^ value.hashCode()}.
2940	>	*
2941	>	* @return the hash code value for this map
2942	>	*/
2943	>	public int hashCode() {
2944	>	int h = 0;
2945	>	Traverser<K,V,Object> it = new Traverser<K,V,Object>(this);
2946	>	Object v;
2947	>	while ((v = it.advance()) != null) {
2948	>	h += it.nextKey.hashCode() ^ v.hashCode();
2949	>	}
2950	>	return h;
2951	>	}
2952	>
2953	>	/**
2954	>	* Returns a string representation of this map.  The string
2955	>	* representation consists of a list of key-value mappings (in no
2956	>	* particular order) enclosed in braces ("{@code {}}").  Adjacent
2957	>	* mappings are separated by the characters {@code ", "} (comma
2958	>	* and space).  Each key-value mapping is rendered as the key
2959	>	* followed by an equals sign ("{@code =}") followed by the
2960	>	* associated value.
2961	>	*
2962	>	* @return a string representation of this map
2963	>	*/
2964	>	public String toString() {
2965	>	Traverser<K,V,Object> it = new Traverser<K,V,Object>(this);
2966	>	StringBuilder sb = new StringBuilder();
2967	>	sb.append('{');
2968	>	Object v;
2969	>	if ((v = it.advance()) != null) {
2970		for (;;) {
2971	<	if (nextTableIndex >= 0) {
2972	<	if ((nextEntry = entryAt(currentTable,
2973	<	nextTableIndex--)) != null)
2974	<	break;
2975	<	}
1237	<	else if (nextSegmentIndex >= 0) {
1238	<	Segment<K,V> seg = segmentAt(segments, nextSegmentIndex--);
1239	<	if (seg != null && (currentTable = seg.table) != null)
1240	<	nextTableIndex = currentTable.length - 1;
1241	<	}
1242	<	else
2971	>	Object k = it.nextKey;
2972	>	sb.append(k == this ? "(this Map)" : k);
2973	>	sb.append('=');
2974	>	sb.append(v == this ? "(this Map)" : v);
2975	>	if ((v = it.advance()) == null)
2976		break;
2977	+	sb.append(',').append(' ');
2978		}
2979		}
2980	+	return sb.append('}').toString();
2981	+	}
2982
2983	<	final HashEntry<K,V> nextEntry() {
2984	<	HashEntry<K,V> e = nextEntry;
2985	<	if (e == null)
2986	<	throw new NoSuchElementException();
2987	<	lastReturned = e; // cannot assign until after null check
2988	<	if ((nextEntry = e.next) == null)
2989	<	advance();
2990	<	return e;
2983	>	/**
2984	>	* Compares the specified object with this map for equality.
2985	>	* Returns {@code true} if the given object is a map with the same
2986	>	* mappings as this map.  This operation may return misleading
2987	>	* results if either map is concurrently modified during execution
2988	>	* of this method.
2989	>	*
2990	>	* @param o object to be compared for equality with this map
2991	>	* @return {@code true} if the specified object is equal to this map
2992	>	*/
2993	>	public boolean equals(Object o) {
2994	>	if (o != this) {
2995	>	if (!(o instanceof Map))
2996	>	return false;
2997	>	Map<?,?> m = (Map<?,?>) o;
2998	>	Traverser<K,V,Object> it = new Traverser<K,V,Object>(this);
2999	>	Object val;
3000	>	while ((val = it.advance()) != null) {
3001	>	Object v = m.get(it.nextKey);
3002	>	if (v == null || (v != val && !v.equals(val)))
3003	>	return false;
3004	>	}
3005	>	for (Map.Entry<?,?> e : m.entrySet()) {
3006	>	Object mk, mv, v;
3007	>	if ((mk = e.getKey()) == null ||
3008	>	(mv = e.getValue()) == null ||
3009	>	(v = internalGet(mk)) == null ||
3010	>	(mv != v && !mv.equals(v)))
3011	>	return false;
3012	>	}
3013		}
3014	+	return true;
3015	+	}
3016
3017	<	public final boolean hasNext() { return nextEntry != null; }
1258	<	public final boolean hasMoreElements() { return nextEntry != null; }
3017	>	/* ----------------Iterators -------------- */
3018
3019	<	public final void remove() {
3020	<	if (lastReturned == null)
3019	>	@SuppressWarnings("serial")
3020	>	static final class KeyIterator<K,V> extends Traverser<K,V,Object>
3021	>	implements Spliterator<K>, Enumeration<K> {
3022	>	KeyIterator(ConcurrentHashMap<K, V> map) { super(map); }
3023	>	KeyIterator(Traverser<K,V,Object> it, boolean split) {
3024	>	super(it, split);
3025	>	}
3026	>	public KeyIterator<K,V> split() {
3027	>	if (last != null || (next != null && nextVal == null))
3028		throw new IllegalStateException();
3029	<	ConcurrentHashMap.this.remove(lastReturned.key);
3030	<	lastReturned = null;
3029	>	return new KeyIterator<K,V>(this, true);
3030	>	}
3031	>	@SuppressWarnings("unchecked")
3032	>	public final K next() {
3033	>	if (nextVal == null && advance() == null)
3034	>	throw new NoSuchElementException();
3035	>	Object k = nextKey;
3036	>	nextVal = null;
3037	>	return (K) k;
3038		}
3039	+
3040	+	public final K nextElement() { return next(); }
3041		}
3042
3043	<	final class KeyIterator
3044	<	extends HashIterator
3045	<	implements Iterator<K>, Enumeration<K>
3046	<	{
3047	<	public final K next()        { return super.nextEntry().key; }
3048	<	public final K nextElement() { return super.nextEntry().key; }
3043	>	@SuppressWarnings("serial")
3044	>	static final class ValueIterator<K,V> extends Traverser<K,V,Object>
3045	>	implements Spliterator<V>, Enumeration<V> {
3046	>	ValueIterator(ConcurrentHashMap<K, V> map) { super(map); }
3047	>	ValueIterator(Traverser<K,V,Object> it, boolean split) {
3048	>	super(it, split);
3049	>	}
3050	>	public ValueIterator<K,V> split() {
3051	>	if (last != null || (next != null && nextVal == null))
3052	>	throw new IllegalStateException();
3053	>	return new ValueIterator<K,V>(this, true);
3054	>	}
3055	>
3056	>	@SuppressWarnings("unchecked")
3057	>	public final V next() {
3058	>	Object v;
3059	>	if ((v = nextVal) == null && (v = advance()) == null)
3060	>	throw new NoSuchElementException();
3061	>	nextVal = null;
3062	>	return (V) v;
3063	>	}
3064	>
3065	>	public final V nextElement() { return next(); }
3066		}
3067
3068	<	final class ValueIterator
3069	<	extends HashIterator
3070	<	implements Iterator<V>, Enumeration<V>
3071	<	{
3072	<	public final V next()        { return super.nextEntry().value; }
3073	<	public final V nextElement() { return super.nextEntry().value; }
3068	>	@SuppressWarnings("serial")
3069	>	static final class EntryIterator<K,V> extends Traverser<K,V,Object>
3070	>	implements Spliterator<Map.Entry<K,V>> {
3071	>	EntryIterator(ConcurrentHashMap<K, V> map) { super(map); }
3072	>	EntryIterator(Traverser<K,V,Object> it, boolean split) {
3073	>	super(it, split);
3074	>	}
3075	>	public EntryIterator<K,V> split() {
3076	>	if (last != null || (next != null && nextVal == null))
3077	>	throw new IllegalStateException();
3078	>	return new EntryIterator<K,V>(this, true);
3079	>	}
3080	>
3081	>	@SuppressWarnings("unchecked")
3082	>	public final Map.Entry<K,V> next() {
3083	>	Object v;
3084	>	if ((v = nextVal) == null && (v = advance()) == null)
3085	>	throw new NoSuchElementException();
3086	>	Object k = nextKey;
3087	>	nextVal = null;
3088	>	return new MapEntry<K,V>((K)k, (V)v, map);
3089	>	}
3090		}
3091
3092		/**
3093	<	* Custom Entry class used by EntryIterator.next(), that relays
1286	<	* setValue changes to the underlying map.
3093	>	* Exported Entry for iterators
3094		*/
3095	<	final class WriteThroughEntry
3096	<	extends AbstractMap.SimpleEntry<K,V>
3097	<	{
3098	<	WriteThroughEntry(K k, V v) {
3099	<	super(k,v);
3095	>	static final class MapEntry<K,V> implements Map.Entry<K, V> {
3096	>	final K key; // non-null
3097	>	V val;       // non-null
3098	>	final ConcurrentHashMap<K, V> map;
3099	>	MapEntry(K key, V val, ConcurrentHashMap<K, V> map) {
3100	>	this.key = key;
3101	>	this.val = val;
3102	>	this.map = map;
3103	>	}
3104	>	public final K getKey()       { return key; }
3105	>	public final V getValue()     { return val; }
3106	>	public final int hashCode()   { return key.hashCode() ^ val.hashCode(); }
3107	>	public final String toString(){ return key + "=" + val; }
3108	>
3109	>	public final boolean equals(Object o) {
3110	>	Object k, v; Map.Entry<?,?> e;
3111	>	return ((o instanceof Map.Entry) &&
3112	>	(k = (e = (Map.Entry<?,?>)o).getKey()) != null &&
3113	>	(v = e.getValue()) != null &&
3114	>	(k == key || k.equals(key)) &&
3115	>	(v == val || v.equals(val)));
3116		}
3117
3118		/**
3119		* Sets our entry's value and writes through to the map. The
3120	<	* value to return is somewhat arbitrary here. Since a
3121	<	* WriteThroughEntry does not necessarily track asynchronous
3122	<	* changes, the most recent "previous" value could be
3123	<	* different from what we return (or could even have been
3124	<	* removed in which case the put will re-establish). We do not
1302	<	* and cannot guarantee more.
3120	>	* value to return is somewhat arbitrary here. Since we do not
3121	>	* necessarily track asynchronous changes, the most recent
3122	>	* "previous" value could be different from what we return (or
3123	>	* could even have been removed in which case the put will
3124	>	* re-establish). We do not and cannot guarantee more.
3125		*/
3126	<	public V setValue(V value) {
3126	>	public final V setValue(V value) {
3127		if (value == null) throw new NullPointerException();
3128	<	V v = super.setValue(value);
3129	<	ConcurrentHashMap.this.put(getKey(), value);
3128	>	V v = val;
3129	>	val = value;
3130	>	map.put(key, value);
3131		return v;
3132		}
3133		}
3134
3135	<	final class EntryIterator
1313	<	extends HashIterator
1314	<	implements Iterator<Entry<K,V>>
1315	<	{
1316	<	public Map.Entry<K,V> next() {
1317	<	HashEntry<K,V> e = super.nextEntry();
1318	<	return new WriteThroughEntry(e.key, e.value);
1319	<	}
1320	<	}
3135	>	/* ----------------Views -------------- */
3136
3137	<	final class KeySet extends AbstractSet<K> {
3138	<	public Iterator<K> iterator() {
3139	<	return new KeyIterator();
3137	>	/**
3138	>	* Base class for views.
3139	>	*/
3140	>	static abstract class CHMView<K, V> {
3141	>	final ConcurrentHashMap<K, V> map;
3142	>	CHMView(ConcurrentHashMap<K, V> map)  { this.map = map; }
3143	>	public final int size()                 { return map.size(); }
3144	>	public final boolean isEmpty()          { return map.isEmpty(); }
3145	>	public final void clear()               { map.clear(); }
3146	>
3147	>	// implementations below rely on concrete classes supplying these
3148	>	abstract public Iterator<?> iterator();
3149	>	abstract public boolean contains(Object o);
3150	>	abstract public boolean remove(Object o);
3151	>
3152	>	private static final String oomeMsg = "Required array size too large";
3153	>
3154	>	public final Object[] toArray() {
3155	>	long sz = map.mappingCount();
3156	>	if (sz > (long)(MAX_ARRAY_SIZE))
3157	>	throw new OutOfMemoryError(oomeMsg);
3158	>	int n = (int)sz;
3159	>	Object[] r = new Object[n];
3160	>	int i = 0;
3161	>	Iterator<?> it = iterator();
3162	>	while (it.hasNext()) {
3163	>	if (i == n) {
3164	>	if (n >= MAX_ARRAY_SIZE)
3165	>	throw new OutOfMemoryError(oomeMsg);
3166	>	if (n >= MAX_ARRAY_SIZE - (MAX_ARRAY_SIZE >>> 1) - 1)
3167	>	n = MAX_ARRAY_SIZE;
3168	>	else
3169	>	n += (n >>> 1) + 1;
3170	>	r = Arrays.copyOf(r, n);
3171	>	}
3172	>	r[i++] = it.next();
3173	>	}
3174	>	return (i == n) ? r : Arrays.copyOf(r, i);
3175		}
3176	<	public int size() {
3177	<	return ConcurrentHashMap.this.size();
3176	>
3177	>	@SuppressWarnings("unchecked")
3178	>	public final <T> T[] toArray(T[] a) {
3179	>	long sz = map.mappingCount();
3180	>	if (sz > (long)(MAX_ARRAY_SIZE))
3181	>	throw new OutOfMemoryError(oomeMsg);
3182	>	int m = (int)sz;
3183	>	T[] r = (a.length >= m) ? a :
3184	>	(T[])java.lang.reflect.Array
3185	>	.newInstance(a.getClass().getComponentType(), m);
3186	>	int n = r.length;
3187	>	int i = 0;
3188	>	Iterator<?> it = iterator();
3189	>	while (it.hasNext()) {
3190	>	if (i == n) {
3191	>	if (n >= MAX_ARRAY_SIZE)
3192	>	throw new OutOfMemoryError(oomeMsg);
3193	>	if (n >= MAX_ARRAY_SIZE - (MAX_ARRAY_SIZE >>> 1) - 1)
3194	>	n = MAX_ARRAY_SIZE;
3195	>	else
3196	>	n += (n >>> 1) + 1;
3197	>	r = Arrays.copyOf(r, n);
3198	>	}
3199	>	r[i++] = (T)it.next();
3200	>	}
3201	>	if (a == r && i < n) {
3202	>	r[i] = null; // null-terminate
3203	>	return r;
3204	>	}
3205	>	return (i == n) ? r : Arrays.copyOf(r, i);
3206		}
3207	<	public boolean isEmpty() {
3208	<	return ConcurrentHashMap.this.isEmpty();
3207	>
3208	>	public final int hashCode() {
3209	>	int h = 0;
3210	>	for (Iterator<?> it = iterator(); it.hasNext();)
3211	>	h += it.next().hashCode();
3212	>	return h;
3213	>	}
3214	>
3215	>	public final String toString() {
3216	>	StringBuilder sb = new StringBuilder();
3217	>	sb.append('[');
3218	>	Iterator<?> it = iterator();
3219	>	if (it.hasNext()) {
3220	>	for (;;) {
3221	>	Object e = it.next();
3222	>	sb.append(e == this ? "(this Collection)" : e);
3223	>	if (!it.hasNext())
3224	>	break;
3225	>	sb.append(',').append(' ');
3226	>	}
3227	>	}
3228	>	return sb.append(']').toString();
3229		}
3230	<	public boolean contains(Object o) {
3231	<	return ConcurrentHashMap.this.containsKey(o);
3230	>
3231	>	public final boolean containsAll(Collection<?> c) {
3232	>	if (c != this) {
3233	>	for (Iterator<?> it = c.iterator(); it.hasNext();) {
3234	>	Object e = it.next();
3235	>	if (e == null || !contains(e))
3236	>	return false;
3237	>	}
3238	>	}
3239	>	return true;
3240		}
3241	<	public boolean remove(Object o) {
3242	<	return ConcurrentHashMap.this.remove(o) != null;
3241	>
3242	>	public final boolean removeAll(Collection<?> c) {
3243	>	boolean modified = false;
3244	>	for (Iterator<?> it = iterator(); it.hasNext();) {
3245	>	if (c.contains(it.next())) {
3246	>	it.remove();
3247	>	modified = true;
3248	>	}
3249	>	}
3250	>	return modified;
3251		}
3252	<	public void clear() {
3253	<	ConcurrentHashMap.this.clear();
3252	>
3253	>	public final boolean retainAll(Collection<?> c) {
3254	>	boolean modified = false;
3255	>	for (Iterator<?> it = iterator(); it.hasNext();) {
3256	>	if (!c.contains(it.next())) {
3257	>	it.remove();
3258	>	modified = true;
3259	>	}
3260	>	}
3261	>	return modified;
3262		}
3263	+
3264		}
3265
3266	<	final class Values extends AbstractCollection<V> {
3267	<	public Iterator<V> iterator() {
3268	<	return new ValueIterator();
3266	>	static final class KeySet<K,V> extends CHMView<K,V> implements Set<K> {
3267	>	KeySet(ConcurrentHashMap<K, V> map)  {
3268	>	super(map);
3269	>	}
3270	>	public final boolean contains(Object o) { return map.containsKey(o); }
3271	>	public final boolean remove(Object o)   { return map.remove(o) != null; }
3272	>	public final Iterator<K> iterator() {
3273	>	return new KeyIterator<K,V>(map);
3274		}
3275	<	public int size() {
3276	<	return ConcurrentHashMap.this.size();
3275	>	public final boolean add(K e) {
3276	>	throw new UnsupportedOperationException();
3277		}
3278	<	public boolean isEmpty() {
3279	<	return ConcurrentHashMap.this.isEmpty();
3278	>	public final boolean addAll(Collection<? extends K> c) {
3279	>	throw new UnsupportedOperationException();
3280		}
3281	<	public boolean contains(Object o) {
3282	<	return ConcurrentHashMap.this.containsValue(o);
3281	>	public boolean equals(Object o) {
3282	>	Set<?> c;
3283	>	return ((o instanceof Set) &&
3284	>	((c = (Set<?>)o) == this ||
3285	>	(containsAll(c) && c.containsAll(this))));
3286		}
3287	<	public void clear() {
3288	<	ConcurrentHashMap.this.clear();
3287	>	}
3288	>
3289	>
3290	>	static final class Values<K,V> extends CHMView<K,V>
3291	>	implements Collection<V> {
3292	>	Values(ConcurrentHashMap<K, V> map)   { super(map); }
3293	>	public final boolean contains(Object o) { return map.containsValue(o); }
3294	>	public final boolean remove(Object o) {
3295	>	if (o != null) {
3296	>	Iterator<V> it = new ValueIterator<K,V>(map);
3297	>	while (it.hasNext()) {
3298	>	if (o.equals(it.next())) {
3299	>	it.remove();
3300	>	return true;
3301	>	}
3302	>	}
3303	>	}
3304	>	return false;
3305		}
3306	+	public final Iterator<V> iterator() {
3307	+	return new ValueIterator<K,V>(map);
3308	+	}
3309	+	public final boolean add(V e) {
3310	+	throw new UnsupportedOperationException();
3311	+	}
3312	+	public final boolean addAll(Collection<? extends V> c) {
3313	+	throw new UnsupportedOperationException();
3314	+	}
3315	+
3316		}
3317
3318	<	final class EntrySet extends AbstractSet<Map.Entry<K,V>> {
3319	<	public Iterator<Map.Entry<K,V>> iterator() {
3320	<	return new EntryIterator();
3318	>	static final class EntrySet<K,V> extends CHMView<K,V>
3319	>	implements Set<Map.Entry<K,V>> {
3320	>	EntrySet(ConcurrentHashMap<K, V> map) { super(map); }
3321	>	public final boolean contains(Object o) {
3322	>	Object k, v, r; Map.Entry<?,?> e;
3323	>	return ((o instanceof Map.Entry) &&
3324	>	(k = (e = (Map.Entry<?,?>)o).getKey()) != null &&
3325	>	(r = map.get(k)) != null &&
3326	>	(v = e.getValue()) != null &&
3327	>	(v == r || v.equals(r)));
3328		}
3329	<	public boolean contains(Object o) {
3330	<	if (!(o instanceof Map.Entry))
3331	<	return false;
3332	<	Map.Entry<?,?> e = (Map.Entry<?,?>)o;
3333	<	V v = ConcurrentHashMap.this.get(e.getKey());
3334	<	return v != null && v.equals(e.getValue());
3329	>	public final boolean remove(Object o) {
3330	>	Object k, v; Map.Entry<?,?> e;
3331	>	return ((o instanceof Map.Entry) &&
3332	>	(k = (e = (Map.Entry<?,?>)o).getKey()) != null &&
3333	>	(v = e.getValue()) != null &&
3334	>	map.remove(k, v));
3335		}
3336	<	public boolean remove(Object o) {
3337	<	if (!(o instanceof Map.Entry))
1374	<	return false;
1375	<	Map.Entry<?,?> e = (Map.Entry<?,?>)o;
1376	<	return ConcurrentHashMap.this.remove(e.getKey(), e.getValue());
3336	>	public final Iterator<Map.Entry<K,V>> iterator() {
3337	>	return new EntryIterator<K,V>(map);
3338		}
3339	<	public int size() {
3340	<	return ConcurrentHashMap.this.size();
3339	>	public final boolean add(Entry<K,V> e) {
3340	>	throw new UnsupportedOperationException();
3341		}
3342	<	public boolean isEmpty() {
3343	<	return ConcurrentHashMap.this.isEmpty();
3342	>	public final boolean addAll(Collection<? extends Entry<K,V>> c) {
3343	>	throw new UnsupportedOperationException();
3344		}
3345	<	public void clear() {
3346	<	ConcurrentHashMap.this.clear();
3345	>	public boolean equals(Object o) {
3346	>	Set<?> c;
3347	>	return ((o instanceof Set) &&
3348	>	((c = (Set<?>)o) == this ||
3349	>	(containsAll(c) && c.containsAll(this))));
3350		}
3351		}
3352
3353		/* ---------------- Serialization Support -------------- */
3354
3355		/**
3356	<	* Saves the state of the <tt>ConcurrentHashMap</tt> instance to a
3356	>	* Stripped-down version of helper class used in previous version,
3357	>	* declared for the sake of serialization compatibility
3358	>	*/
3359	>	static class Segment<K,V> implements Serializable {
3360	>	private static final long serialVersionUID = 2249069246763182397L;
3361	>	final float loadFactor;
3362	>	Segment(float lf) { this.loadFactor = lf; }
3363	>	}
3364	>
3365	>	/**
3366	>	* Saves the state of the {@code ConcurrentHashMap} instance to a
3367		* stream (i.e., serializes it).
3368		* @param s the stream
3369		* @serialData
#	Line 1397 | Line 3371 | public class ConcurrentHashMap<K, V> ext
3371		* for each key-value mapping, followed by a null pair.
3372		* The key-value mappings are emitted in no particular order.
3373		*/
3374	<	private void writeObject(java.io.ObjectOutputStream s) throws IOException {
3375	<	// force all segments for serialization compatibility
3376	<	for (int k = 0; k < segments.length; ++k)
3377	<	ensureSegment(k);
3374	>	@SuppressWarnings("unchecked")
3375	>	private void writeObject(java.io.ObjectOutputStream s)
3376	>	throws java.io.IOException {
3377	>	if (segments == null) { // for serialization compatibility
3378	>	segments = (Segment<K,V>[])
3379	>	new Segment<?,?>[DEFAULT_CONCURRENCY_LEVEL];
3380	>	for (int i = 0; i < segments.length; ++i)
3381	>	segments[i] = new Segment<K,V>(LOAD_FACTOR);
3382	>	}
3383		s.defaultWriteObject();
3384	<
3385	<	final Segment<K,V>[] segments = this.segments;
3386	<	for (int k = 0; k < segments.length; ++k) {
3387	<	Segment<K,V> seg = segmentAt(segments, k);
3388	<	seg.lock();
1410	<	try {
1411	<	HashEntry<K,V>[] tab = seg.table;
1412	<	for (int i = 0; i < tab.length; ++i) {
1413	<	HashEntry<K,V> e;
1414	<	for (e = entryAt(tab, i); e != null; e = e.next) {
1415	<	s.writeObject(e.key);
1416	<	s.writeObject(e.value);
1417	<	}
1418	<	}
1419	<	} finally {
1420	<	seg.unlock();
1421	<	}
3384	>	Traverser<K,V,Object> it = new Traverser<K,V,Object>(this);
3385	>	Object v;
3386	>	while ((v = it.advance()) != null) {
3387	>	s.writeObject(it.nextKey);
3388	>	s.writeObject(v);
3389		}
3390		s.writeObject(null);
3391		s.writeObject(null);
3392	+	segments = null; // throw away
3393		}
3394
3395		/**
3396	<	* Reconstitutes the <tt>ConcurrentHashMap</tt> instance from a
1429	<	* stream (i.e., deserializes it).
3396	>	* Reconstitutes the instance from a stream (that is, deserializes it).
3397		* @param s the stream
3398		*/
3399		@SuppressWarnings("unchecked")
3400	<	private void readObject(java.io.ObjectInputStream s)
3401	<	throws IOException, ClassNotFoundException {
3400	>	private void readObject(java.io.ObjectInputStream s)
3401	>	throws java.io.IOException, ClassNotFoundException {
3402		s.defaultReadObject();
3403	+	this.segments = null; // unneeded
3404	+	// initialize transient final field
3405	+	UNSAFE.putObjectVolatile(this, counterOffset, new LongAdder());
3406
3407	<	// Re-initialize segments to be minimally sized, and let grow.
3408	<	int cap = MIN_SEGMENT_TABLE_CAPACITY;
3409	<	final Segment<K,V>[] segments = this.segments;
3410	<	for (int k = 0; k < segments.length; ++k) {
3411	<	Segment<K,V> seg = segments[k];
3412	<	if (seg != null) {
3413	<	seg.threshold = (int)(cap * seg.loadFactor);
3414	<	seg.table = (HashEntry<K,V>[]) new HashEntry<?,?>[cap];
3407	>	// Create all nodes, then place in table once size is known
3408	>	long size = 0L;
3409	>	Node p = null;
3410	>	for (;;) {
3411	>	K k = (K) s.readObject();
3412	>	V v = (V) s.readObject();
3413	>	if (k != null && v != null) {
3414	>	int h = spread(k.hashCode());
3415	>	p = new Node(h, k, v, p);
3416	>	++size;
3417		}
3418	+	else
3419	+	break;
3420		}
3421	+	if (p != null) {
3422	+	boolean init = false;
3423	+	int n;
3424	+	if (size >= (long)(MAXIMUM_CAPACITY >>> 1))
3425	+	n = MAXIMUM_CAPACITY;
3426	+	else {
3427	+	int sz = (int)size;
3428	+	n = tableSizeFor(sz + (sz >>> 1) + 1);
3429	+	}
3430	+	int sc = sizeCtl;
3431	+	boolean collide = false;
3432	+	if (n > sc &&
3433	+	UNSAFE.compareAndSwapInt(this, sizeCtlOffset, sc, -1)) {
3434	+	try {
3435	+	if (table == null) {
3436	+	init = true;
3437	+	Node[] tab = new Node[n];
3438	+	int mask = n - 1;
3439	+	while (p != null) {
3440	+	int j = p.hash & mask;
3441	+	Node next = p.next;
3442	+	Node q = p.next = tabAt(tab, j);
3443	+	setTabAt(tab, j, p);
3444	+	if (!collide && q != null && q.hash == p.hash)
3445	+	collide = true;
3446	+	p = next;
3447	+	}
3448	+	table = tab;
3449	+	counter.add(size);
3450	+	sc = n - (n >>> 2);
3451	+	}
3452	+	} finally {
3453	+	sizeCtl = sc;
3454	+	}
3455	+	if (collide) { // rescan and convert to TreeBins
3456	+	Node[] tab = table;
3457	+	for (int i = 0; i < tab.length; ++i) {
3458	+	int c = 0;
3459	+	for (Node e = tabAt(tab, i); e != null; e = e.next) {
3460	+	if (++c > TREE_THRESHOLD &&
3461	+	(e.key instanceof Comparable)) {
3462	+	replaceWithTreeBin(tab, i, e.key);
3463	+	break;
3464	+	}
3465	+	}
3466	+	}
3467	+	}
3468	+	}
3469	+	if (!init) { // Can only happen if unsafely published.
3470	+	while (p != null) {
3471	+	internalPut(p.key, p.val);
3472	+	p = p.next;
3473	+	}
3474	+	}
3475	+	}
3476	+	}
3477
3478	<	// Read the keys and values, and put the mappings in the table
3479	<	for (;;) {
3480	<	K key = (K) s.readObject();
3481	<	V value = (V) s.readObject();
3482	<	if (key == null)
3483	<	break;
3484	<	put(key, value);
3478	>
3479	>	// -------------------------------------------------------
3480	>
3481	>	// Sams
3482	>	/** Interface describing a void action of one argument */
3483	>	public interface Action<A> { void apply(A a); }
3484	>	/** Interface describing a void action of two arguments */
3485	>	public interface BiAction<A,B> { void apply(A a, B b); }
3486	>	/** Interface describing a function of one argument */
3487	>	public interface Fun<A,T> { T apply(A a); }
3488	>	/** Interface describing a function of two arguments */
3489	>	public interface BiFun<A,B,T> { T apply(A a, B b); }
3490	>	/** Interface describing a function of no arguments */
3491	>	public interface Generator<T> { T apply(); }
3492	>	/** Interface describing a function mapping its argument to a double */
3493	>	public interface ObjectToDouble<A> { double apply(A a); }
3494	>	/** Interface describing a function mapping its argument to a long */
3495	>	public interface ObjectToLong<A> { long apply(A a); }
3496	>	/** Interface describing a function mapping its argument to an int */
3497	>	public interface ObjectToInt<A> {int apply(A a); }
3498	>	/** Interface describing a function mapping two arguments to a double */
3499	>	public interface ObjectByObjectToDouble<A,B> { double apply(A a, B b); }
3500	>	/** Interface describing a function mapping two arguments to a long */
3501	>	public interface ObjectByObjectToLong<A,B> { long apply(A a, B b); }
3502	>	/** Interface describing a function mapping two arguments to an int */
3503	>	public interface ObjectByObjectToInt<A,B> {int apply(A a, B b); }
3504	>	/** Interface describing a function mapping a double to a double */
3505	>	public interface DoubleToDouble { double apply(double a); }
3506	>	/** Interface describing a function mapping a long to a long */
3507	>	public interface LongToLong { long apply(long a); }
3508	>	/** Interface describing a function mapping an int to an int */
3509	>	public interface IntToInt { int apply(int a); }
3510	>	/** Interface describing a function mapping two doubles to a double */
3511	>	public interface DoubleByDoubleToDouble { double apply(double a, double b); }
3512	>	/** Interface describing a function mapping two longs to a long */
3513	>	public interface LongByLongToLong { long apply(long a, long b); }
3514	>	/** Interface describing a function mapping two ints to an int */
3515	>	public interface IntByIntToInt { int apply(int a, int b); }
3516	>
3517	>
3518	>	// -------------------------------------------------------
3519	>
3520	>	/**
3521	>	* Returns an extended {@link Parallel} view of this map using the
3522	>	* given executor for bulk parallel operations.
3523	>	*
3524	>	* @param executor the executor
3525	>	* @return a parallel view
3526	>	*/
3527	>	public Parallel parallel(ForkJoinPool executor)  {
3528	>	return new Parallel(executor);
3529	>	}
3530	>
3531	>	/**
3532	>	* An extended view of a ConcurrentHashMap supporting bulk
3533	>	* parallel operations. These operations are designed to be
3534	>	* safely, and often sensibly, applied even with maps that are
3535	>	* being concurrently updated by other threads; for example, when
3536	>	* computing a snapshot summary of the values in a shared
3537	>	* registry.  There are three kinds of operation, each with four
3538	>	* forms, accepting functions with Keys, Values, Entries, and
3539	>	* (Key, Value) arguments and/or return values. Because the
3540	>	* elements of a ConcurrentHashMap are not ordered in any
3541	>	* particular way, and may be processed in different orders in
3542	>	* different parallel executions, the correctness of supplied
3543	>	* functions should not depend on any ordering, or on any other
3544	>	* objects or values that may transiently change while computation
3545	>	* is in progress; and except for forEach actions, should ideally
3546	>	* be side-effect-free.
3547	>	*
3548	>	* <ul>
3549	>	* <li> forEach: Perform a given action on each element.
3550	>	* A variant form applies a given transformation on each element
3551	>	* before performing the action.</li>
3552	>	*
3553	>	* <li> search: Return the first available non-null result of
3554	>	* applying a given function on each element; skipping further
3555	>	* search when a result is found.</li>
3556	>	*
3557	>	* <li> reduce: Accumulate each element.  The supplied reduction
3558	>	* function cannot rely on ordering (more formally, it should be
3559	>	* both associative and commutative).  There are five variants:
3560	>	*
3561	>	* <ul>
3562	>	*
3563	>	* <li> Plain reductions. (There is not a form of this method for
3564	>	* (key, value) function arguments since there is no corresponding
3565	>	* return type.)</li>
3566	>	*
3567	>	* <li> Mapped reductions that accumulate the results of a given
3568	>	* function applied to each element.</li>
3569	>	*
3570	>	* <li> Reductions to scalar doubles, longs, and ints, using a
3571	>	* given basis value.</li>
3572	>	*
3573	>	* </li>
3574	>	* </ul>
3575	>	* </ul>
3576	>	*
3577	>	* <p>The concurrency properties of the bulk operations follow
3578	>	* from those of ConcurrentHashMap: Any non-null result returned
3579	>	* from {@code get(key)} and related access methods bears a
3580	>	* happens-before relation with the associated insertion or
3581	>	* update.  The result of any bulk operation reflects the
3582	>	* composition of these per-element relations (but is not
3583	>	* necessarily atomic with respect to the map as a whole unless it
3584	>	* is somehow known to be quiescent).  Conversely, because keys
3585	>	* and values in the map are never null, null serves as a reliable
3586	>	* atomic indicator of the current lack of any result.  To
3587	>	* maintain this property, null serves as an implicit basis for
3588	>	* all non-scalar reduction operations. For the double, long, and
3589	>	* int versions, the basis should be one that, when combined with
3590	>	* any other value, returns that other value (more formally, it
3591	>	* should be the identity element for the reduction). Most common
3592	>	* reductions have these properties; for example, computing a sum
3593	>	* with basis 0 or a minimum with basis MAX_VALUE.
3594	>	*
3595	>	* <p>Search and transformation functions provided as arguments
3596	>	* should similarly return null to indicate the lack of any result
3597	>	* (in which case it is not used). In the case of mapped
3598	>	* reductions, this also enables transformations to serve as
3599	>	* filters, returning null (or, in the case of primitive
3600	>	* specializations, the identity basis) if the element should not
3601	>	* be combined. You can create compound transformations and
3602	>	* filterings by composing them yourself under this "null means
3603	>	* there is nothing there now" rule before using them in search or
3604	>	* reduce operations.
3605	>	*
3606	>	* <p>Methods accepting and/or returning Entry arguments maintain
3607	>	* key-value associations. They may be useful for example when
3608	>	* finding the key for the greatest value. Note that "plain" Entry
3609	>	* arguments can be supplied using {@code new
3610	>	* AbstractMap.SimpleEntry(k,v)}.
3611	>	*
3612	>	* <p> Bulk operations may complete abruptly, throwing an
3613	>	* exception encountered in the application of a supplied
3614	>	* function. Bear in mind when handling such exceptions that other
3615	>	* concurrently executing functions could also have thrown
3616	>	* exceptions, or would have done so if the first exception had
3617	>	* not occurred.
3618	>	*
3619	>	* <p>Parallel speedups compared to sequential processing are
3620	>	* common but not guaranteed.  Operations involving brief
3621	>	* functions on small maps may execute more slowly than sequential
3622	>	* loops if the underlying work to parallelize the computation is
3623	>	* more expensive than the computation itself. Similarly,
3624	>	* parallelization may not lead to much actual parallelism if all
3625	>	* processors are busy performing unrelated tasks.
3626	>	*
3627	>	* <p> All arguments to all task methods must be non-null.
3628	>	*
3629	>	* <p><em>jsr166e note: During transition, this class
3630	>	* uses nested functional interfaces with different names but the
3631	>	* same forms as those expected for JDK8.<em>
3632	>	*/
3633	>	public class Parallel {
3634	>	final ForkJoinPool fjp;
3635	>
3636	>	/**
3637	>	* Returns an extended view of this map using the given
3638	>	* executor for bulk parallel operations.
3639	>	*
3640	>	* @param executor the executor
3641	>	*/
3642	>	public Parallel(ForkJoinPool executor)  {
3643	>	this.fjp = executor;
3644	>	}
3645	>
3646	>	/**
3647	>	* Performs the given action for each (key, value).
3648	>	*
3649	>	* @param action the action
3650	>	*/
3651	>	public void forEach(BiAction<K,V> action) {
3652	>	fjp.invoke(ForkJoinTasks.forEach
3653	>	(ConcurrentHashMap.this, action));
3654	>	}
3655	>
3656	>	/**
3657	>	* Performs the given action for each non-null transformation
3658	>	* of each (key, value).
3659	>	*
3660	>	* @param transformer a function returning the transformation
3661	>	* for an element, or null of there is no transformation (in
3662	>	* which case the action is not applied).
3663	>	* @param action the action
3664	>	*/
3665	>	public <U> void forEach(BiFun<? super K, ? super V, ? extends U> transformer,
3666	>	Action<U> action) {
3667	>	fjp.invoke(ForkJoinTasks.forEach
3668	>	(ConcurrentHashMap.this, transformer, action));
3669	>	}
3670	>
3671	>	/**
3672	>	* Returns a non-null result from applying the given search
3673	>	* function on each (key, value), or null if none.  Upon
3674	>	* success, further element processing is suppressed and the
3675	>	* results of any other parallel invocations of the search
3676	>	* function are ignored.
3677	>	*
3678	>	* @param searchFunction a function returning a non-null
3679	>	* result on success, else null
3680	>	* @return a non-null result from applying the given search
3681	>	* function on each (key, value), or null if none
3682	>	*/
3683	>	public <U> U search(BiFun<? super K, ? super V, ? extends U> searchFunction) {
3684	>	return fjp.invoke(ForkJoinTasks.search
3685	>	(ConcurrentHashMap.this, searchFunction));
3686	>	}
3687	>
3688	>	/**
3689	>	* Returns the result of accumulating the given transformation
3690	>	* of all (key, value) pairs using the given reducer to
3691	>	* combine values, or null if none.
3692	>	*
3693	>	* @param transformer a function returning the transformation
3694	>	* for an element, or null of there is no transformation (in
3695	>	* which case it is not combined).
3696	>	* @param reducer a commutative associative combining function
3697	>	* @return the result of accumulating the given transformation
3698	>	* of all (key, value) pairs
3699	>	*/
3700	>	public <U> U reduce(BiFun<? super K, ? super V, ? extends U> transformer,
3701	>	BiFun<? super U, ? super U, ? extends U> reducer) {
3702	>	return fjp.invoke(ForkJoinTasks.reduce
3703	>	(ConcurrentHashMap.this, transformer, reducer));
3704	>	}
3705	>
3706	>	/**
3707	>	* Returns the result of accumulating the given transformation
3708	>	* of all (key, value) pairs using the given reducer to
3709	>	* combine values, and the given basis as an identity value.
3710	>	*
3711	>	* @param transformer a function returning the transformation
3712	>	* for an element
3713	>	* @param basis the identity (initial default value) for the reduction
3714	>	* @param reducer a commutative associative combining function
3715	>	* @return the result of accumulating the given transformation
3716	>	* of all (key, value) pairs
3717	>	*/
3718	>	public double reduceToDouble(ObjectByObjectToDouble<? super K, ? super V> transformer,
3719	>	double basis,
3720	>	DoubleByDoubleToDouble reducer) {
3721	>	return fjp.invoke(ForkJoinTasks.reduceToDouble
3722	>	(ConcurrentHashMap.this, transformer, basis, reducer));
3723	>	}
3724	>
3725	>	/**
3726	>	* Returns the result of accumulating the given transformation
3727	>	* of all (key, value) pairs using the given reducer to
3728	>	* combine values, and the given basis as an identity value.
3729	>	*
3730	>	* @param transformer a function returning the transformation
3731	>	* for an element
3732	>	* @param basis the identity (initial default value) for the reduction
3733	>	* @param reducer a commutative associative combining function
3734	>	* @return the result of accumulating the given transformation
3735	>	* of all (key, value) pairs
3736	>	*/
3737	>	public long reduceToLong(ObjectByObjectToLong<? super K, ? super V> transformer,
3738	>	long basis,
3739	>	LongByLongToLong reducer) {
3740	>	return fjp.invoke(ForkJoinTasks.reduceToLong
3741	>	(ConcurrentHashMap.this, transformer, basis, reducer));
3742	>	}
3743	>
3744	>	/**
3745	>	* Returns the result of accumulating the given transformation
3746	>	* of all (key, value) pairs using the given reducer to
3747	>	* combine values, and the given basis as an identity value.
3748	>	*
3749	>	* @param transformer a function returning the transformation
3750	>	* for an element
3751	>	* @param basis the identity (initial default value) for the reduction
3752	>	* @param reducer a commutative associative combining function
3753	>	* @return the result of accumulating the given transformation
3754	>	* of all (key, value) pairs
3755	>	*/
3756	>	public int reduceToInt(ObjectByObjectToInt<? super K, ? super V> transformer,
3757	>	int basis,
3758	>	IntByIntToInt reducer) {
3759	>	return fjp.invoke(ForkJoinTasks.reduceToInt
3760	>	(ConcurrentHashMap.this, transformer, basis, reducer));
3761	>	}
3762	>
3763	>	/**
3764	>	* Performs the given action for each key.
3765	>	*
3766	>	* @param action the action
3767	>	*/
3768	>	public void forEachKey(Action<K> action) {
3769	>	fjp.invoke(ForkJoinTasks.forEachKey
3770	>	(ConcurrentHashMap.this, action));
3771	>	}
3772	>
3773	>	/**
3774	>	* Performs the given action for each non-null transformation
3775	>	* of each key.
3776	>	*
3777	>	* @param transformer a function returning the transformation
3778	>	* for an element, or null of there is no transformation (in
3779	>	* which case the action is not applied).
3780	>	* @param action the action
3781	>	*/
3782	>	public <U> void forEachKey(Fun<? super K, ? extends U> transformer,
3783	>	Action<U> action) {
3784	>	fjp.invoke(ForkJoinTasks.forEachKey
3785	>	(ConcurrentHashMap.this, transformer, action));
3786	>	}
3787	>
3788	>	/**
3789	>	* Returns a non-null result from applying the given search
3790	>	* function on each key, or null if none. Upon success,
3791	>	* further element processing is suppressed and the results of
3792	>	* any other parallel invocations of the search function are
3793	>	* ignored.
3794	>	*
3795	>	* @param searchFunction a function returning a non-null
3796	>	* result on success, else null
3797	>	* @return a non-null result from applying the given search
3798	>	* function on each key, or null if none
3799	>	*/
3800	>	public <U> U searchKeys(Fun<? super K, ? extends U> searchFunction) {
3801	>	return fjp.invoke(ForkJoinTasks.searchKeys
3802	>	(ConcurrentHashMap.this, searchFunction));
3803	>	}
3804	>
3805	>	/**
3806	>	* Returns the result of accumulating all keys using the given
3807	>	* reducer to combine values, or null if none.
3808	>	*
3809	>	* @param reducer a commutative associative combining function
3810	>	* @return the result of accumulating all keys using the given
3811	>	* reducer to combine values, or null if none
3812	>	*/
3813	>	public K reduceKeys(BiFun<? super K, ? super K, ? extends K> reducer) {
3814	>	return fjp.invoke(ForkJoinTasks.reduceKeys
3815	>	(ConcurrentHashMap.this, reducer));
3816	>	}
3817	>
3818	>	/**
3819	>	* Returns the result of accumulating the given transformation
3820	>	* of all keys using the given reducer to combine values, or
3821	>	* null if none.
3822	>	*
3823	>	* @param transformer a function returning the transformation
3824	>	* for an element, or null of there is no transformation (in
3825	>	* which case it is not combined).
3826	>	* @param reducer a commutative associative combining function
3827	>	* @return the result of accumulating the given transformation
3828	>	* of all keys
3829	>	*/
3830	>	public <U> U reduceKeys(Fun<? super K, ? extends U> transformer,
3831	>	BiFun<? super U, ? super U, ? extends U> reducer) {
3832	>	return fjp.invoke(ForkJoinTasks.reduceKeys
3833	>	(ConcurrentHashMap.this, transformer, reducer));
3834	>	}
3835	>
3836	>	/**
3837	>	* Returns the result of accumulating the given transformation
3838	>	* of all keys using the given reducer to combine values, and
3839	>	* the given basis as an identity value.
3840	>	*
3841	>	* @param transformer a function returning the transformation
3842	>	* for an element
3843	>	* @param basis the identity (initial default value) for the reduction
3844	>	* @param reducer a commutative associative combining function
3845	>	* @return  the result of accumulating the given transformation
3846	>	* of all keys
3847	>	*/
3848	>	public double reduceKeysToDouble(ObjectToDouble<? super K> transformer,
3849	>	double basis,
3850	>	DoubleByDoubleToDouble reducer) {
3851	>	return fjp.invoke(ForkJoinTasks.reduceKeysToDouble
3852	>	(ConcurrentHashMap.this, transformer, basis, reducer));
3853	>	}
3854	>
3855	>	/**
3856	>	* Returns the result of accumulating the given transformation
3857	>	* of all keys using the given reducer to combine values, and
3858	>	* the given basis as an identity value.
3859	>	*
3860	>	* @param transformer a function returning the transformation
3861	>	* for an element
3862	>	* @param basis the identity (initial default value) for the reduction
3863	>	* @param reducer a commutative associative combining function
3864	>	* @return the result of accumulating the given transformation
3865	>	* of all keys
3866	>	*/
3867	>	public long reduceKeysToLong(ObjectToLong<? super K> transformer,
3868	>	long basis,
3869	>	LongByLongToLong reducer) {
3870	>	return fjp.invoke(ForkJoinTasks.reduceKeysToLong
3871	>	(ConcurrentHashMap.this, transformer, basis, reducer));
3872	>	}
3873	>
3874	>	/**
3875	>	* Returns the result of accumulating the given transformation
3876	>	* of all keys using the given reducer to combine values, and
3877	>	* the given basis as an identity value.
3878	>	*
3879	>	* @param transformer a function returning the transformation
3880	>	* for an element
3881	>	* @param basis the identity (initial default value) for the reduction
3882	>	* @param reducer a commutative associative combining function
3883	>	* @return the result of accumulating the given transformation
3884	>	* of all keys
3885	>	*/
3886	>	public int reduceKeysToInt(ObjectToInt<? super K> transformer,
3887	>	int basis,
3888	>	IntByIntToInt reducer) {
3889	>	return fjp.invoke(ForkJoinTasks.reduceKeysToInt
3890	>	(ConcurrentHashMap.this, transformer, basis, reducer));
3891	>	}
3892	>
3893	>	/**
3894	>	* Performs the given action for each value.
3895	>	*
3896	>	* @param action the action
3897	>	*/
3898	>	public void forEachValue(Action<V> action) {
3899	>	fjp.invoke(ForkJoinTasks.forEachValue
3900	>	(ConcurrentHashMap.this, action));
3901	>	}
3902	>
3903	>	/**
3904	>	* Performs the given action for each non-null transformation
3905	>	* of each value.
3906	>	*
3907	>	* @param transformer a function returning the transformation
3908	>	* for an element, or null of there is no transformation (in
3909	>	* which case the action is not applied).
3910	>	*/
3911	>	public <U> void forEachValue(Fun<? super V, ? extends U> transformer,
3912	>	Action<U> action) {
3913	>	fjp.invoke(ForkJoinTasks.forEachValue
3914	>	(ConcurrentHashMap.this, transformer, action));
3915	>	}
3916	>
3917	>	/**
3918	>	* Returns a non-null result from applying the given search
3919	>	* function on each value, or null if none.  Upon success,
3920	>	* further element processing is suppressed and the results of
3921	>	* any other parallel invocations of the search function are
3922	>	* ignored.
3923	>	*
3924	>	* @param searchFunction a function returning a non-null
3925	>	* result on success, else null
3926	>	* @return a non-null result from applying the given search
3927	>	* function on each value, or null if none
3928	>	*
3929	>	*/
3930	>	public <U> U searchValues(Fun<? super V, ? extends U> searchFunction) {
3931	>	return fjp.invoke(ForkJoinTasks.searchValues
3932	>	(ConcurrentHashMap.this, searchFunction));
3933	>	}
3934	>
3935	>	/**
3936	>	* Returns the result of accumulating all values using the
3937	>	* given reducer to combine values, or null if none.
3938	>	*
3939	>	* @param reducer a commutative associative combining function
3940	>	* @return  the result of accumulating all values
3941	>	*/
3942	>	public V reduceValues(BiFun<? super V, ? super V, ? extends V> reducer) {
3943	>	return fjp.invoke(ForkJoinTasks.reduceValues
3944	>	(ConcurrentHashMap.this, reducer));
3945	>	}
3946	>
3947	>	/**
3948	>	* Returns the result of accumulating the given transformation
3949	>	* of all values using the given reducer to combine values, or
3950	>	* null if none.
3951	>	*
3952	>	* @param transformer a function returning the transformation
3953	>	* for an element, or null of there is no transformation (in
3954	>	* which case it is not combined).
3955	>	* @param reducer a commutative associative combining function
3956	>	* @return the result of accumulating the given transformation
3957	>	* of all values
3958	>	*/
3959	>	public <U> U reduceValues(Fun<? super V, ? extends U> transformer,
3960	>	BiFun<? super U, ? super U, ? extends U> reducer) {
3961	>	return fjp.invoke(ForkJoinTasks.reduceValues
3962	>	(ConcurrentHashMap.this, transformer, reducer));
3963	>	}
3964	>
3965	>	/**
3966	>	* Returns the result of accumulating the given transformation
3967	>	* of all values using the given reducer to combine values,
3968	>	* and the given basis as an identity value.
3969	>	*
3970	>	* @param transformer a function returning the transformation
3971	>	* for an element
3972	>	* @param basis the identity (initial default value) for the reduction
3973	>	* @param reducer a commutative associative combining function
3974	>	* @return the result of accumulating the given transformation
3975	>	* of all values
3976	>	*/
3977	>	public double reduceValuesToDouble(ObjectToDouble<? super V> transformer,
3978	>	double basis,
3979	>	DoubleByDoubleToDouble reducer) {
3980	>	return fjp.invoke(ForkJoinTasks.reduceValuesToDouble
3981	>	(ConcurrentHashMap.this, transformer, basis, reducer));
3982	>	}
3983	>
3984	>	/**
3985	>	* Returns the result of accumulating the given transformation
3986	>	* of all values using the given reducer to combine values,
3987	>	* and the given basis as an identity value.
3988	>	*
3989	>	* @param transformer a function returning the transformation
3990	>	* for an element
3991	>	* @param basis the identity (initial default value) for the reduction
3992	>	* @param reducer a commutative associative combining function
3993	>	* @return the result of accumulating the given transformation
3994	>	* of all values
3995	>	*/
3996	>	public long reduceValuesToLong(ObjectToLong<? super V> transformer,
3997	>	long basis,
3998	>	LongByLongToLong reducer) {
3999	>	return fjp.invoke(ForkJoinTasks.reduceValuesToLong
4000	>	(ConcurrentHashMap.this, transformer, basis, reducer));
4001	>	}
4002	>
4003	>	/**
4004	>	* Returns the result of accumulating the given transformation
4005	>	* of all values using the given reducer to combine values,
4006	>	* and the given basis as an identity value.
4007	>	*
4008	>	* @param transformer a function returning the transformation
4009	>	* for an element
4010	>	* @param basis the identity (initial default value) for the reduction
4011	>	* @param reducer a commutative associative combining function
4012	>	* @return the result of accumulating the given transformation
4013	>	* of all values
4014	>	*/
4015	>	public int reduceValuesToInt(ObjectToInt<? super V> transformer,
4016	>	int basis,
4017	>	IntByIntToInt reducer) {
4018	>	return fjp.invoke(ForkJoinTasks.reduceValuesToInt
4019	>	(ConcurrentHashMap.this, transformer, basis, reducer));
4020	>	}
4021	>
4022	>	/**
4023	>	* Performs the given action for each entry.
4024	>	*
4025	>	* @param action the action
4026	>	*/
4027	>	public void forEachEntry(Action<Map.Entry<K,V>> action) {
4028	>	fjp.invoke(ForkJoinTasks.forEachEntry
4029	>	(ConcurrentHashMap.this, action));
4030	>	}
4031	>
4032	>	/**
4033	>	* Performs the given action for each non-null transformation
4034	>	* of each entry.
4035	>	*
4036	>	* @param transformer a function returning the transformation
4037	>	* for an element, or null of there is no transformation (in
4038	>	* which case the action is not applied).
4039	>	* @param action the action
4040	>	*/
4041	>	public <U> void forEachEntry(Fun<Map.Entry<K,V>, ? extends U> transformer,
4042	>	Action<U> action) {
4043	>	fjp.invoke(ForkJoinTasks.forEachEntry
4044	>	(ConcurrentHashMap.this, transformer, action));
4045	>	}
4046	>
4047	>	/**
4048	>	* Returns a non-null result from applying the given search
4049	>	* function on each entry, or null if none.  Upon success,
4050	>	* further element processing is suppressed and the results of
4051	>	* any other parallel invocations of the search function are
4052	>	* ignored.
4053	>	*
4054	>	* @param searchFunction a function returning a non-null
4055	>	* result on success, else null
4056	>	* @return a non-null result from applying the given search
4057	>	* function on each entry, or null if none
4058	>	*/
4059	>	public <U> U searchEntries(Fun<Map.Entry<K,V>, ? extends U> searchFunction) {
4060	>	return fjp.invoke(ForkJoinTasks.searchEntries
4061	>	(ConcurrentHashMap.this, searchFunction));
4062	>	}
4063	>
4064	>	/**
4065	>	* Returns the result of accumulating all entries using the
4066	>	* given reducer to combine values, or null if none.
4067	>	*
4068	>	* @param reducer a commutative associative combining function
4069	>	* @return the result of accumulating all entries
4070	>	*/
4071	>	public Map.Entry<K,V> reduceEntries(BiFun<Map.Entry<K,V>, Map.Entry<K,V>, ? extends Map.Entry<K,V>> reducer) {
4072	>	return fjp.invoke(ForkJoinTasks.reduceEntries
4073	>	(ConcurrentHashMap.this, reducer));
4074	>	}
4075	>
4076	>	/**
4077	>	* Returns the result of accumulating the given transformation
4078	>	* of all entries using the given reducer to combine values,
4079	>	* or null if none.
4080	>	*
4081	>	* @param transformer a function returning the transformation
4082	>	* for an element, or null of there is no transformation (in
4083	>	* which case it is not combined).
4084	>	* @param reducer a commutative associative combining function
4085	>	* @return the result of accumulating the given transformation
4086	>	* of all entries
4087	>	*/
4088	>	public <U> U reduceEntries(Fun<Map.Entry<K,V>, ? extends U> transformer,
4089	>	BiFun<? super U, ? super U, ? extends U> reducer) {
4090	>	return fjp.invoke(ForkJoinTasks.reduceEntries
4091	>	(ConcurrentHashMap.this, transformer, reducer));
4092	>	}
4093	>
4094	>	/**
4095	>	* Returns the result of accumulating the given transformation
4096	>	* of all entries using the given reducer to combine values,
4097	>	* and the given basis as an identity value.
4098	>	*
4099	>	* @param transformer a function returning the transformation
4100	>	* for an element
4101	>	* @param basis the identity (initial default value) for the reduction
4102	>	* @param reducer a commutative associative combining function
4103	>	* @return the result of accumulating the given transformation
4104	>	* of all entries
4105	>	*/
4106	>	public double reduceEntriesToDouble(ObjectToDouble<Map.Entry<K,V>> transformer,
4107	>	double basis,
4108	>	DoubleByDoubleToDouble reducer) {
4109	>	return fjp.invoke(ForkJoinTasks.reduceEntriesToDouble
4110	>	(ConcurrentHashMap.this, transformer, basis, reducer));
4111	>	}
4112	>
4113	>	/**
4114	>	* Returns the result of accumulating the given transformation
4115	>	* of all entries using the given reducer to combine values,
4116	>	* and the given basis as an identity value.
4117	>	*
4118	>	* @param transformer a function returning the transformation
4119	>	* for an element
4120	>	* @param basis the identity (initial default value) for the reduction
4121	>	* @param reducer a commutative associative combining function
4122	>	* @return  the result of accumulating the given transformation
4123	>	* of all entries
4124	>	*/
4125	>	public long reduceEntriesToLong(ObjectToLong<Map.Entry<K,V>> transformer,
4126	>	long basis,
4127	>	LongByLongToLong reducer) {
4128	>	return fjp.invoke(ForkJoinTasks.reduceEntriesToLong
4129	>	(ConcurrentHashMap.this, transformer, basis, reducer));
4130	>	}
4131	>
4132	>	/**
4133	>	* Returns the result of accumulating the given transformation
4134	>	* of all entries using the given reducer to combine values,
4135	>	* and the given basis as an identity value.
4136	>	*
4137	>	* @param transformer a function returning the transformation
4138	>	* for an element
4139	>	* @param basis the identity (initial default value) for the reduction
4140	>	* @param reducer a commutative associative combining function
4141	>	* @return the result of accumulating the given transformation
4142	>	* of all entries
4143	>	*/
4144	>	public int reduceEntriesToInt(ObjectToInt<Map.Entry<K,V>> transformer,
4145	>	int basis,
4146	>	IntByIntToInt reducer) {
4147	>	return fjp.invoke(ForkJoinTasks.reduceEntriesToInt
4148	>	(ConcurrentHashMap.this, transformer, basis, reducer));
4149	>	}
4150	>	}
4151	>
4152	>	// ---------------------------------------------------------------------
4153	>
4154	>	/**
4155	>	* Predefined tasks for performing bulk parallel operations on
4156	>	* ConcurrentHashMaps. These tasks follow the forms and rules used
4157	>	* in class {@link Parallel}. Each method has the same name, but
4158	>	* returns a task rather than invoking it. These methods may be
4159	>	* useful in custom applications such as submitting a task without
4160	>	* waiting for completion, or combining with other tasks.
4161	>	*/
4162	>	public static class ForkJoinTasks {
4163	>	private ForkJoinTasks() {}
4164	>
4165	>	/**
4166	>	* Returns a task that when invoked, performs the given
4167	>	* action for each (key, value)
4168	>	*
4169	>	* @param map the map
4170	>	* @param action the action
4171	>	* @return the task
4172	>	*/
4173	>	public static <K,V> ForkJoinTask<Void> forEach
4174	>	(ConcurrentHashMap<K,V> map,
4175	>	BiAction<K,V> action) {
4176	>	if (action == null) throw new NullPointerException();
4177	>	return new ForEachMappingTask<K,V>(map, action);
4178	>	}
4179	>
4180	>	/**
4181	>	* Returns a task that when invoked, performs the given
4182	>	* action for each non-null transformation of each (key, value)
4183	>	*
4184	>	* @param map the map
4185	>	* @param transformer a function returning the transformation
4186	>	* for an element, or null of there is no transformation (in
4187	>	* which case the action is not applied).
4188	>	* @param action the action
4189	>	* @return the task
4190	>	*/
4191	>	public static <K,V,U> ForkJoinTask<Void> forEach
4192	>	(ConcurrentHashMap<K,V> map,
4193	>	BiFun<? super K, ? super V, ? extends U> transformer,
4194	>	Action<U> action) {
4195	>	if (transformer == null || action == null)
4196	>	throw new NullPointerException();
4197	>	return new ForEachTransformedMappingTask<K,V,U>
4198	>	(map, transformer, action);
4199	>	}
4200	>
4201	>	/**
4202	>	* Returns a task that when invoked, returns a non-null result
4203	>	* from applying the given search function on each (key,
4204	>	* value), or null if none. Upon success, further element
4205	>	* processing is suppressed and the results of any other
4206	>	* parallel invocations of the search function are ignored.
4207	>	*
4208	>	* @param map the map
4209	>	* @param searchFunction a function returning a non-null
4210	>	* result on success, else null
4211	>	* @return the task
4212	>	*/
4213	>	public static <K,V,U> ForkJoinTask<U> search
4214	>	(ConcurrentHashMap<K,V> map,
4215	>	BiFun<? super K, ? super V, ? extends U> searchFunction) {
4216	>	if (searchFunction == null) throw new NullPointerException();
4217	>	return new SearchMappingsTask<K,V,U>
4218	>	(map, searchFunction,
4219	>	new AtomicReference<U>());
4220	>	}
4221	>
4222	>	/**
4223	>	* Returns a task that when invoked, returns the result of
4224	>	* accumulating the given transformation of all (key, value) pairs
4225	>	* using the given reducer to combine values, or null if none.
4226	>	*
4227	>	* @param map the map
4228	>	* @param transformer a function returning the transformation
4229	>	* for an element, or null of there is no transformation (in
4230	>	* which case it is not combined).
4231	>	* @param reducer a commutative associative combining function
4232	>	* @return the task
4233	>	*/
4234	>	public static <K,V,U> ForkJoinTask<U> reduce
4235	>	(ConcurrentHashMap<K,V> map,
4236	>	BiFun<? super K, ? super V, ? extends U> transformer,
4237	>	BiFun<? super U, ? super U, ? extends U> reducer) {
4238	>	if (transformer == null || reducer == null)
4239	>	throw new NullPointerException();
4240	>	return new MapReduceMappingsTask<K,V,U>
4241	>	(map, transformer, reducer);
4242	>	}
4243	>
4244	>	/**
4245	>	* Returns a task that when invoked, returns the result of
4246	>	* accumulating the given transformation of all (key, value) pairs
4247	>	* using the given reducer to combine values, and the given
4248	>	* basis as an identity value.
4249	>	*
4250	>	* @param map the map
4251	>	* @param transformer a function returning the transformation
4252	>	* for an element
4253	>	* @param basis the identity (initial default value) for the reduction
4254	>	* @param reducer a commutative associative combining function
4255	>	* @return the task
4256	>	*/
4257	>	public static <K,V> ForkJoinTask<Double> reduceToDouble
4258	>	(ConcurrentHashMap<K,V> map,
4259	>	ObjectByObjectToDouble<? super K, ? super V> transformer,
4260	>	double basis,
4261	>	DoubleByDoubleToDouble reducer) {
4262	>	if (transformer == null || reducer == null)
4263	>	throw new NullPointerException();
4264	>	return new MapReduceMappingsToDoubleTask<K,V>
4265	>	(map, transformer, basis, reducer);
4266	>	}
4267	>
4268	>	/**
4269	>	* Returns a task that when invoked, returns the result of
4270	>	* accumulating the given transformation of all (key, value) pairs
4271	>	* using the given reducer to combine values, and the given
4272	>	* basis as an identity value.
4273	>	*
4274	>	* @param map the map
4275	>	* @param transformer a function returning the transformation
4276	>	* for an element
4277	>	* @param basis the identity (initial default value) for the reduction
4278	>	* @param reducer a commutative associative combining function
4279	>	* @return the task
4280	>	*/
4281	>	public static <K,V> ForkJoinTask<Long> reduceToLong
4282	>	(ConcurrentHashMap<K,V> map,
4283	>	ObjectByObjectToLong<? super K, ? super V> transformer,
4284	>	long basis,
4285	>	LongByLongToLong reducer) {
4286	>	if (transformer == null || reducer == null)
4287	>	throw new NullPointerException();
4288	>	return new MapReduceMappingsToLongTask<K,V>
4289	>	(map, transformer, basis, reducer);
4290	>	}
4291	>
4292	>	/**
4293	>	* Returns a task that when invoked, returns the result of
4294	>	* accumulating the given transformation of all (key, value) pairs
4295	>	* using the given reducer to combine values, and the given
4296	>	* basis as an identity value.
4297	>	*
4298	>	* @param transformer a function returning the transformation
4299	>	* for an element
4300	>	* @param basis the identity (initial default value) for the reduction
4301	>	* @param reducer a commutative associative combining function
4302	>	* @return the task
4303	>	*/
4304	>	public static <K,V> ForkJoinTask<Integer> reduceToInt
4305	>	(ConcurrentHashMap<K,V> map,
4306	>	ObjectByObjectToInt<? super K, ? super V> transformer,
4307	>	int basis,
4308	>	IntByIntToInt reducer) {
4309	>	if (transformer == null || reducer == null)
4310	>	throw new NullPointerException();
4311	>	return new MapReduceMappingsToIntTask<K,V>
4312	>	(map, transformer, basis, reducer);
4313	>	}
4314	>
4315	>	/**
4316	>	* Returns a task that when invoked, performs the given action
4317	>	* for each key.
4318	>	*
4319	>	* @param map the map
4320	>	* @param action the action
4321	>	* @return the task
4322	>	*/
4323	>	public static <K,V> ForkJoinTask<Void> forEachKey
4324	>	(ConcurrentHashMap<K,V> map,
4325	>	Action<K> action) {
4326	>	if (action == null) throw new NullPointerException();
4327	>	return new ForEachKeyTask<K,V>(map, action);
4328	>	}
4329	>
4330	>	/**
4331	>	* Returns a task that when invoked, performs the given action
4332	>	* for each non-null transformation of each key.
4333	>	*
4334	>	* @param map the map
4335	>	* @param transformer a function returning the transformation
4336	>	* for an element, or null of there is no transformation (in
4337	>	* which case the action is not applied).
4338	>	* @param action the action
4339	>	* @return the task
4340	>	*/
4341	>	public static <K,V,U> ForkJoinTask<Void> forEachKey
4342	>	(ConcurrentHashMap<K,V> map,
4343	>	Fun<? super K, ? extends U> transformer,
4344	>	Action<U> action) {
4345	>	if (transformer == null || action == null)
4346	>	throw new NullPointerException();
4347	>	return new ForEachTransformedKeyTask<K,V,U>
4348	>	(map, transformer, action);
4349	>	}
4350	>
4351	>	/**
4352	>	* Returns a task that when invoked, returns a non-null result
4353	>	* from applying the given search function on each key, or
4354	>	* null if none.  Upon success, further element processing is
4355	>	* suppressed and the results of any other parallel
4356	>	* invocations of the search function are ignored.
4357	>	*
4358	>	* @param map the map
4359	>	* @param searchFunction a function returning a non-null
4360	>	* result on success, else null
4361	>	* @return the task
4362	>	*/
4363	>	public static <K,V,U> ForkJoinTask<U> searchKeys
4364	>	(ConcurrentHashMap<K,V> map,
4365	>	Fun<? super K, ? extends U> searchFunction) {
4366	>	if (searchFunction == null) throw new NullPointerException();
4367	>	return new SearchKeysTask<K,V,U>
4368	>	(map, searchFunction,
4369	>	new AtomicReference<U>());
4370	>	}
4371	>
4372	>	/**
4373	>	* Returns a task that when invoked, returns the result of
4374	>	* accumulating all keys using the given reducer to combine
4375	>	* values, or null if none.
4376	>	*
4377	>	* @param map the map
4378	>	* @param reducer a commutative associative combining function
4379	>	* @return the task
4380	>	*/
4381	>	public static <K,V> ForkJoinTask<K> reduceKeys
4382	>	(ConcurrentHashMap<K,V> map,
4383	>	BiFun<? super K, ? super K, ? extends K> reducer) {
4384	>	if (reducer == null) throw new NullPointerException();
4385	>	return new ReduceKeysTask<K,V>
4386	>	(map, reducer);
4387	>	}
4388	>
4389	>	/**
4390	>	* Returns a task that when invoked, returns the result of
4391	>	* accumulating the given transformation of all keys using the given
4392	>	* reducer to combine values, or null if none.
4393	>	*
4394	>	* @param map the map
4395	>	* @param transformer a function returning the transformation
4396	>	* for an element, or null of there is no transformation (in
4397	>	* which case it is not combined).
4398	>	* @param reducer a commutative associative combining function
4399	>	* @return the task
4400	>	*/
4401	>	public static <K,V,U> ForkJoinTask<U> reduceKeys
4402	>	(ConcurrentHashMap<K,V> map,
4403	>	Fun<? super K, ? extends U> transformer,
4404	>	BiFun<? super U, ? super U, ? extends U> reducer) {
4405	>	if (transformer == null || reducer == null)
4406	>	throw new NullPointerException();
4407	>	return new MapReduceKeysTask<K,V,U>
4408	>	(map, transformer, reducer);
4409	>	}
4410	>
4411	>	/**
4412	>	* Returns a task that when invoked, returns the result of
4413	>	* accumulating the given transformation of all keys using the given
4414	>	* reducer to combine values, and the given basis as an
4415	>	* identity value.
4416	>	*
4417	>	* @param map the map
4418	>	* @param transformer a function returning the transformation
4419	>	* for an element
4420	>	* @param basis the identity (initial default value) for the reduction
4421	>	* @param reducer a commutative associative combining function
4422	>	* @return the task
4423	>	*/
4424	>	public static <K,V> ForkJoinTask<Double> reduceKeysToDouble
4425	>	(ConcurrentHashMap<K,V> map,
4426	>	ObjectToDouble<? super K> transformer,
4427	>	double basis,
4428	>	DoubleByDoubleToDouble reducer) {
4429	>	if (transformer == null || reducer == null)
4430	>	throw new NullPointerException();
4431	>	return new MapReduceKeysToDoubleTask<K,V>
4432	>	(map, transformer, basis, reducer);
4433	>	}
4434	>
4435	>	/**
4436	>	* Returns a task that when invoked, returns the result of
4437	>	* accumulating the given transformation of all keys using the given
4438	>	* reducer to combine values, and the given basis as an
4439	>	* identity value.
4440	>	*
4441	>	* @param map the map
4442	>	* @param transformer a function returning the transformation
4443	>	* for an element
4444	>	* @param basis the identity (initial default value) for the reduction
4445	>	* @param reducer a commutative associative combining function
4446	>	* @return the task
4447	>	*/
4448	>	public static <K,V> ForkJoinTask<Long> reduceKeysToLong
4449	>	(ConcurrentHashMap<K,V> map,
4450	>	ObjectToLong<? super K> transformer,
4451	>	long basis,
4452	>	LongByLongToLong reducer) {
4453	>	if (transformer == null || reducer == null)
4454	>	throw new NullPointerException();
4455	>	return new MapReduceKeysToLongTask<K,V>
4456	>	(map, transformer, basis, reducer);
4457	>	}
4458	>
4459	>	/**
4460	>	* Returns a task that when invoked, returns the result of
4461	>	* accumulating the given transformation of all keys using the given
4462	>	* reducer to combine values, and the given basis as an
4463	>	* identity value.
4464	>	*
4465	>	* @param map the map
4466	>	* @param transformer a function returning the transformation
4467	>	* for an element
4468	>	* @param basis the identity (initial default value) for the reduction
4469	>	* @param reducer a commutative associative combining function
4470	>	* @return the task
4471	>	*/
4472	>	public static <K,V> ForkJoinTask<Integer> reduceKeysToInt
4473	>	(ConcurrentHashMap<K,V> map,
4474	>	ObjectToInt<? super K> transformer,
4475	>	int basis,
4476	>	IntByIntToInt reducer) {
4477	>	if (transformer == null || reducer == null)
4478	>	throw new NullPointerException();
4479	>	return new MapReduceKeysToIntTask<K,V>
4480	>	(map, transformer, basis, reducer);
4481	>	}
4482	>
4483	>	/**
4484	>	* Returns a task that when invoked, performs the given action
4485	>	* for each value.
4486	>	*
4487	>	* @param map the map
4488	>	* @param action the action
4489	>	*/
4490	>	public static <K,V> ForkJoinTask<Void> forEachValue
4491	>	(ConcurrentHashMap<K,V> map,
4492	>	Action<V> action) {
4493	>	if (action == null) throw new NullPointerException();
4494	>	return new ForEachValueTask<K,V>(map, action);
4495	>	}
4496	>
4497	>	/**
4498	>	* Returns a task that when invoked, performs the given action
4499	>	* for each non-null transformation of each value.
4500	>	*
4501	>	* @param map the map
4502	>	* @param transformer a function returning the transformation
4503	>	* for an element, or null of there is no transformation (in
4504	>	* which case the action is not applied).
4505	>	* @param action the action
4506	>	*/
4507	>	public static <K,V,U> ForkJoinTask<Void> forEachValue
4508	>	(ConcurrentHashMap<K,V> map,
4509	>	Fun<? super V, ? extends U> transformer,
4510	>	Action<U> action) {
4511	>	if (transformer == null || action == null)
4512	>	throw new NullPointerException();
4513	>	return new ForEachTransformedValueTask<K,V,U>
4514	>	(map, transformer, action);
4515	>	}
4516	>
4517	>	/**
4518	>	* Returns a task that when invoked, returns a non-null result
4519	>	* from applying the given search function on each value, or
4520	>	* null if none.  Upon success, further element processing is
4521	>	* suppressed and the results of any other parallel
4522	>	* invocations of the search function are ignored.
4523	>	*
4524	>	* @param map the map
4525	>	* @param searchFunction a function returning a non-null
4526	>	* result on success, else null
4527	>	* @return the task
4528	>	*
4529	>	*/
4530	>	public static <K,V,U> ForkJoinTask<U> searchValues
4531	>	(ConcurrentHashMap<K,V> map,
4532	>	Fun<? super V, ? extends U> searchFunction) {
4533	>	if (searchFunction == null) throw new NullPointerException();
4534	>	return new SearchValuesTask<K,V,U>
4535	>	(map, searchFunction,
4536	>	new AtomicReference<U>());
4537	>	}
4538	>
4539	>	/**
4540	>	* Returns a task that when invoked, returns the result of
4541	>	* accumulating all values using the given reducer to combine
4542	>	* values, or null if none.
4543	>	*
4544	>	* @param map the map
4545	>	* @param reducer a commutative associative combining function
4546	>	* @return the task
4547	>	*/
4548	>	public static <K,V> ForkJoinTask<V> reduceValues
4549	>	(ConcurrentHashMap<K,V> map,
4550	>	BiFun<? super V, ? super V, ? extends V> reducer) {
4551	>	if (reducer == null) throw new NullPointerException();
4552	>	return new ReduceValuesTask<K,V>
4553	>	(map, reducer);
4554	>	}
4555	>
4556	>	/**
4557	>	* Returns a task that when invoked, returns the result of
4558	>	* accumulating the given transformation of all values using the
4559	>	* given reducer to combine values, or null if none.
4560	>	*
4561	>	* @param map the map
4562	>	* @param transformer a function returning the transformation
4563	>	* for an element, or null of there is no transformation (in
4564	>	* which case it is not combined).
4565	>	* @param reducer a commutative associative combining function
4566	>	* @return the task
4567	>	*/
4568	>	public static <K,V,U> ForkJoinTask<U> reduceValues
4569	>	(ConcurrentHashMap<K,V> map,
4570	>	Fun<? super V, ? extends U> transformer,
4571	>	BiFun<? super U, ? super U, ? extends U> reducer) {
4572	>	if (transformer == null || reducer == null)
4573	>	throw new NullPointerException();
4574	>	return new MapReduceValuesTask<K,V,U>
4575	>	(map, transformer, reducer);
4576	>	}
4577	>
4578	>	/**
4579	>	* Returns a task that when invoked, returns the result of
4580	>	* accumulating the given transformation of all values using the
4581	>	* given reducer to combine values, and the given basis as an
4582	>	* identity value.
4583	>	*
4584	>	* @param map the map
4585	>	* @param transformer a function returning the transformation
4586	>	* for an element
4587	>	* @param basis the identity (initial default value) for the reduction
4588	>	* @param reducer a commutative associative combining function
4589	>	* @return the task
4590	>	*/
4591	>	public static <K,V> ForkJoinTask<Double> reduceValuesToDouble
4592	>	(ConcurrentHashMap<K,V> map,
4593	>	ObjectToDouble<? super V> transformer,
4594	>	double basis,
4595	>	DoubleByDoubleToDouble reducer) {
4596	>	if (transformer == null || reducer == null)
4597	>	throw new NullPointerException();
4598	>	return new MapReduceValuesToDoubleTask<K,V>
4599	>	(map, transformer, basis, reducer);
4600	>	}
4601	>
4602	>	/**
4603	>	* Returns a task that when invoked, returns the result of
4604	>	* accumulating the given transformation of all values using the
4605	>	* given reducer to combine values, and the given basis as an
4606	>	* identity value.
4607	>	*
4608	>	* @param map the map
4609	>	* @param transformer a function returning the transformation
4610	>	* for an element
4611	>	* @param basis the identity (initial default value) for the reduction
4612	>	* @param reducer a commutative associative combining function
4613	>	* @return the task
4614	>	*/
4615	>	public static <K,V> ForkJoinTask<Long> reduceValuesToLong
4616	>	(ConcurrentHashMap<K,V> map,
4617	>	ObjectToLong<? super V> transformer,
4618	>	long basis,
4619	>	LongByLongToLong reducer) {
4620	>	if (transformer == null || reducer == null)
4621	>	throw new NullPointerException();
4622	>	return new MapReduceValuesToLongTask<K,V>
4623	>	(map, transformer, basis, reducer);
4624	>	}
4625	>
4626	>	/**
4627	>	* Returns a task that when invoked, returns the result of
4628	>	* accumulating the given transformation of all values using the
4629	>	* given reducer to combine values, and the given basis as an
4630	>	* identity value.
4631	>	*
4632	>	* @param map the map
4633	>	* @param transformer a function returning the transformation
4634	>	* for an element
4635	>	* @param basis the identity (initial default value) for the reduction
4636	>	* @param reducer a commutative associative combining function
4637	>	* @return the task
4638	>	*/
4639	>	public static <K,V> ForkJoinTask<Integer> reduceValuesToInt
4640	>	(ConcurrentHashMap<K,V> map,
4641	>	ObjectToInt<? super V> transformer,
4642	>	int basis,
4643	>	IntByIntToInt reducer) {
4644	>	if (transformer == null || reducer == null)
4645	>	throw new NullPointerException();
4646	>	return new MapReduceValuesToIntTask<K,V>
4647	>	(map, transformer, basis, reducer);
4648	>	}
4649	>
4650	>	/**
4651	>	* Returns a task that when invoked, perform the given action
4652	>	* for each entry.
4653	>	*
4654	>	* @param map the map
4655	>	* @param action the action
4656	>	*/
4657	>	public static <K,V> ForkJoinTask<Void> forEachEntry
4658	>	(ConcurrentHashMap<K,V> map,
4659	>	Action<Map.Entry<K,V>> action) {
4660	>	if (action == null) throw new NullPointerException();
4661	>	return new ForEachEntryTask<K,V>(map, action);
4662	>	}
4663	>
4664	>	/**
4665	>	* Returns a task that when invoked, perform the given action
4666	>	* for each non-null transformation of each entry.
4667	>	*
4668	>	* @param map the map
4669	>	* @param transformer a function returning the transformation
4670	>	* for an element, or null of there is no transformation (in
4671	>	* which case the action is not applied).
4672	>	* @param action the action
4673	>	*/
4674	>	public static <K,V,U> ForkJoinTask<Void> forEachEntry
4675	>	(ConcurrentHashMap<K,V> map,
4676	>	Fun<Map.Entry<K,V>, ? extends U> transformer,
4677	>	Action<U> action) {
4678	>	if (transformer == null || action == null)
4679	>	throw new NullPointerException();
4680	>	return new ForEachTransformedEntryTask<K,V,U>
4681	>	(map, transformer, action);
4682	>	}
4683	>
4684	>	/**
4685	>	* Returns a task that when invoked, returns a non-null result
4686	>	* from applying the given search function on each entry, or
4687	>	* null if none.  Upon success, further element processing is
4688	>	* suppressed and the results of any other parallel
4689	>	* invocations of the search function are ignored.
4690	>	*
4691	>	* @param map the map
4692	>	* @param searchFunction a function returning a non-null
4693	>	* result on success, else null
4694	>	* @return the task
4695	>	*
4696	>	*/
4697	>	public static <K,V,U> ForkJoinTask<U> searchEntries
4698	>	(ConcurrentHashMap<K,V> map,
4699	>	Fun<Map.Entry<K,V>, ? extends U> searchFunction) {
4700	>	if (searchFunction == null) throw new NullPointerException();
4701	>	return new SearchEntriesTask<K,V,U>
4702	>	(map, searchFunction,
4703	>	new AtomicReference<U>());
4704	>	}
4705	>
4706	>	/**
4707	>	* Returns a task that when invoked, returns the result of
4708	>	* accumulating all entries using the given reducer to combine
4709	>	* values, or null if none.
4710	>	*
4711	>	* @param map the map
4712	>	* @param reducer a commutative associative combining function
4713	>	* @return the task
4714	>	*/
4715	>	public static <K,V> ForkJoinTask<Map.Entry<K,V>> reduceEntries
4716	>	(ConcurrentHashMap<K,V> map,
4717	>	BiFun<Map.Entry<K,V>, Map.Entry<K,V>, ? extends Map.Entry<K,V>> reducer) {
4718	>	if (reducer == null) throw new NullPointerException();
4719	>	return new ReduceEntriesTask<K,V>
4720	>	(map, reducer);
4721	>	}
4722	>
4723	>	/**
4724	>	* Returns a task that when invoked, returns the result of
4725	>	* accumulating the given transformation of all entries using the
4726	>	* given reducer to combine values, or null if none.
4727	>	*
4728	>	* @param map the map
4729	>	* @param transformer a function returning the transformation
4730	>	* for an element, or null of there is no transformation (in
4731	>	* which case it is not combined).
4732	>	* @param reducer a commutative associative combining function
4733	>	* @return the task
4734	>	*/
4735	>	public static <K,V,U> ForkJoinTask<U> reduceEntries
4736	>	(ConcurrentHashMap<K,V> map,
4737	>	Fun<Map.Entry<K,V>, ? extends U> transformer,
4738	>	BiFun<? super U, ? super U, ? extends U> reducer) {
4739	>	if (transformer == null || reducer == null)
4740	>	throw new NullPointerException();
4741	>	return new MapReduceEntriesTask<K,V,U>
4742	>	(map, transformer, reducer);
4743	>	}
4744	>
4745	>	/**
4746	>	* Returns a task that when invoked, returns the result of
4747	>	* accumulating the given transformation of all entries using the
4748	>	* given reducer to combine values, and the given basis as an
4749	>	* identity value.
4750	>	*
4751	>	* @param map the map
4752	>	* @param transformer a function returning the transformation
4753	>	* for an element
4754	>	* @param basis the identity (initial default value) for the reduction
4755	>	* @param reducer a commutative associative combining function
4756	>	* @return the task
4757	>	*/
4758	>	public static <K,V> ForkJoinTask<Double> reduceEntriesToDouble
4759	>	(ConcurrentHashMap<K,V> map,
4760	>	ObjectToDouble<Map.Entry<K,V>> transformer,
4761	>	double basis,
4762	>	DoubleByDoubleToDouble reducer) {
4763	>	if (transformer == null || reducer == null)
4764	>	throw new NullPointerException();
4765	>	return new MapReduceEntriesToDoubleTask<K,V>
4766	>	(map, transformer, basis, reducer);
4767	>	}
4768	>
4769	>	/**
4770	>	* Returns a task that when invoked, returns the result of
4771	>	* accumulating the given transformation of all entries using the
4772	>	* given reducer to combine values, and the given basis as an
4773	>	* identity value.
4774	>	*
4775	>	* @param map the map
4776	>	* @param transformer a function returning the transformation
4777	>	* for an element
4778	>	* @param basis the identity (initial default value) for the reduction
4779	>	* @param reducer a commutative associative combining function
4780	>	* @return the task
4781	>	*/
4782	>	public static <K,V> ForkJoinTask<Long> reduceEntriesToLong
4783	>	(ConcurrentHashMap<K,V> map,
4784	>	ObjectToLong<Map.Entry<K,V>> transformer,
4785	>	long basis,
4786	>	LongByLongToLong reducer) {
4787	>	if (transformer == null || reducer == null)
4788	>	throw new NullPointerException();
4789	>	return new MapReduceEntriesToLongTask<K,V>
4790	>	(map, transformer, basis, reducer);
4791	>	}
4792	>
4793	>	/**
4794	>	* Returns a task that when invoked, returns the result of
4795	>	* accumulating the given transformation of all entries using the
4796	>	* given reducer to combine values, and the given basis as an
4797	>	* identity value.
4798	>	*
4799	>	* @param map the map
4800	>	* @param transformer a function returning the transformation
4801	>	* for an element
4802	>	* @param basis the identity (initial default value) for the reduction
4803	>	* @param reducer a commutative associative combining function
4804	>	* @return the task
4805	>	*/
4806	>	public static <K,V> ForkJoinTask<Integer> reduceEntriesToInt
4807	>	(ConcurrentHashMap<K,V> map,
4808	>	ObjectToInt<Map.Entry<K,V>> transformer,
4809	>	int basis,
4810	>	IntByIntToInt reducer) {
4811	>	if (transformer == null || reducer == null)
4812	>	throw new NullPointerException();
4813	>	return new MapReduceEntriesToIntTask<K,V>
4814	>	(map, transformer, basis, reducer);
4815	>	}
4816	>	}
4817	>
4818	>	// -------------------------------------------------------
4819	>
4820	>	/**
4821	>	* Base for FJ tasks for bulk operations. This adds a variant of
4822	>	* CountedCompleters and some split and merge bookkeeping to
4823	>	* iterator functionality. The forEach and reduce methods are
4824	>	* similar to those illustrated in CountedCompleter documentation,
4825	>	* except that bottom-up reduction completions perform them within
4826	>	* their compute methods. The search methods are like forEach
4827	>	* except they continually poll for success and exit early.  Also,
4828	>	* exceptions are handled in a simpler manner, by just trying to
4829	>	* complete root task exceptionally.
4830	>	*/
4831	>	@SuppressWarnings("serial")
4832	>	static abstract class BulkTask<K,V,R> extends Traverser<K,V,R> {
4833	>	final BulkTask<K,V,?> parent;  // completion target
4834	>	int batch;                     // split control
4835	>	int pending;                   // completion control
4836	>
4837	>	/** Constructor for root tasks */
4838	>	BulkTask(ConcurrentHashMap<K,V> map) {
4839	>	super(map);
4840	>	this.parent = null;
4841	>	this.batch = -1; // force call to batch() on execution
4842	>	}
4843	>
4844	>	/** Constructor for subtasks */
4845	>	BulkTask(BulkTask<K,V,?> parent, int batch, boolean split) {
4846	>	super(parent, split);
4847	>	this.parent = parent;
4848	>	this.batch = batch;
4849	>	}
4850	>
4851	>	// FJ methods
4852	>
4853	>	/**
4854	>	* Propagates completion. Note that all reduce actions
4855	>	* bypass this method to combine while completing.
4856	>	*/
4857	>	final void tryComplete() {
4858	>	BulkTask<K,V,?> a = this, s = a;
4859	>	for (int c;;) {
4860	>	if ((c = a.pending) == 0) {
4861	>	if ((a = (s = a).parent) == null) {
4862	>	s.quietlyComplete();
4863	>	break;
4864	>	}
4865	>	}
4866	>	else if (U.compareAndSwapInt(a, PENDING, c, c - 1))
4867	>	break;
4868	>	}
4869	>	}
4870	>
4871	>	/**
4872	>	* Forces root task to throw exception unless already complete.
4873	>	*/
4874	>	final void tryAbortComputation(Throwable ex) {
4875	>	for (BulkTask<K,V,?> a = this;;) {
4876	>	BulkTask<K,V,?> p = a.parent;
4877	>	if (p == null) {
4878	>	a.completeExceptionally(ex);
4879	>	break;
4880	>	}
4881	>	a = p;
4882	>	}
4883	>	}
4884	>
4885	>	public final boolean exec() {
4886	>	try {
4887	>	compute();
4888	>	}
4889	>	catch (Throwable ex) {
4890	>	tryAbortComputation(ex);
4891	>	}
4892	>	return false;
4893	>	}
4894	>
4895	>	public abstract void compute();
4896	>
4897	>	// utilities
4898	>
4899	>	/** CompareAndSet pending count */
4900	>	final boolean casPending(int cmp, int val) {
4901	>	return U.compareAndSwapInt(this, PENDING, cmp, val);
4902	>	}
4903	>
4904	>	/**
4905	>	* Returns approx exp2 of the number of times (minus one) to
4906	>	* split task by two before executing leaf action. This value
4907	>	* is faster to compute and more convenient to use as a guide
4908	>	* to splitting than is the depth, since it is used while
4909	>	* dividing by two anyway.
4910	>	*/
4911	>	final int batch() {
4912	>	int b = batch;
4913	>	if (b < 0) {
4914	>	long n = map.counter.sum();
4915	>	int sp = getPool().getParallelism() << 3; // slack of 8
4916	>	b = batch = (n <= 0L) ? 0 : (n < (long)sp) ? (int)n : sp;
4917	>	}
4918	>	return b;
4919	>	}
4920	>
4921	>	/**
4922	>	* Error message for hoisted null checks of functions
4923	>	*/
4924	>	static final String NullFunctionMessage =
4925	>	"Unexpected null function";
4926	>
4927	>	/**
4928	>	* Returns exportable snapshot entry.
4929	>	*/
4930	>	static <K,V> AbstractMap.SimpleEntry<K,V> entryFor(K k, V v) {
4931	>	return new AbstractMap.SimpleEntry<K,V>(k, v);
4932	>	}
4933	>
4934	>	// Unsafe mechanics
4935	>	private static final sun.misc.Unsafe U;
4936	>	private static final long PENDING;
4937	>	static {
4938	>	try {
4939	>	U = sun.misc.Unsafe.getUnsafe();
4940	>	PENDING = U.objectFieldOffset
4941	>	(BulkTask.class.getDeclaredField("pending"));
4942	>	} catch (Exception e) {
4943	>	throw new Error(e);
4944	>	}
4945	>	}
4946	>	}
4947	>
4948	>	/*
4949	>	* Task classes. Coded in a regular but ugly format/style to
4950	>	* simplify checks that each variant differs in the right way from
4951	>	* others.
4952	>	*/
4953	>
4954	>	@SuppressWarnings("serial")
4955	>	static final class ForEachKeyTask<K,V>
4956	>	extends BulkTask<K,V,Void> {
4957	>	final Action<K> action;
4958	>	ForEachKeyTask
4959	>	(ConcurrentHashMap<K,V> m,
4960	>	Action<K> action) {
4961	>	super(m);
4962	>	this.action = action;
4963	>	}
4964	>	ForEachKeyTask
4965	>	(BulkTask<K,V,?> p, int b, boolean split,
4966	>	Action<K> action) {
4967	>	super(p, b, split);
4968	>	this.action = action;
4969	>	}
4970	>	@SuppressWarnings("unchecked") public final void compute() {
4971	>	final Action<K> action = this.action;
4972	>	if (action == null)
4973	>	throw new Error(NullFunctionMessage);
4974	>	int b = batch(), c;
4975	>	while (b > 1 && baseIndex != baseLimit) {
4976	>	do {} while (!casPending(c = pending, c+1));
4977	>	new ForEachKeyTask<K,V>(this, b >>>= 1, true, action).fork();
4978	>	}
4979	>	while (advance() != null)
4980	>	action.apply((K)nextKey);
4981	>	tryComplete();
4982	>	}
4983	>	}
4984	>
4985	>	@SuppressWarnings("serial")
4986	>	static final class ForEachValueTask<K,V>
4987	>	extends BulkTask<K,V,Void> {
4988	>	final Action<V> action;
4989	>	ForEachValueTask
4990	>	(ConcurrentHashMap<K,V> m,
4991	>	Action<V> action) {
4992	>	super(m);
4993	>	this.action = action;
4994	>	}
4995	>	ForEachValueTask
4996	>	(BulkTask<K,V,?> p, int b, boolean split,
4997	>	Action<V> action) {
4998	>	super(p, b, split);
4999	>	this.action = action;
5000	>	}
5001	>	@SuppressWarnings("unchecked") public final void compute() {
5002	>	final Action<V> action = this.action;
5003	>	if (action == null)
5004	>	throw new Error(NullFunctionMessage);
5005	>	int b = batch(), c;
5006	>	while (b > 1 && baseIndex != baseLimit) {
5007	>	do {} while (!casPending(c = pending, c+1));
5008	>	new ForEachValueTask<K,V>(this, b >>>= 1, true, action).fork();
5009	>	}
5010	>	Object v;
5011	>	while ((v = advance()) != null)
5012	>	action.apply((V)v);
5013	>	tryComplete();
5014	>	}
5015	>	}
5016	>
5017	>	@SuppressWarnings("serial")
5018	>	static final class ForEachEntryTask<K,V>
5019	>	extends BulkTask<K,V,Void> {
5020	>	final Action<Entry<K,V>> action;
5021	>	ForEachEntryTask
5022	>	(ConcurrentHashMap<K,V> m,
5023	>	Action<Entry<K,V>> action) {
5024	>	super(m);
5025	>	this.action = action;
5026	>	}
5027	>	ForEachEntryTask
5028	>	(BulkTask<K,V,?> p, int b, boolean split,
5029	>	Action<Entry<K,V>> action) {
5030	>	super(p, b, split);
5031	>	this.action = action;
5032	>	}
5033	>	@SuppressWarnings("unchecked") public final void compute() {
5034	>	final Action<Entry<K,V>> action = this.action;
5035	>	if (action == null)
5036	>	throw new Error(NullFunctionMessage);
5037	>	int b = batch(), c;
5038	>	while (b > 1 && baseIndex != baseLimit) {
5039	>	do {} while (!casPending(c = pending, c+1));
5040	>	new ForEachEntryTask<K,V>(this, b >>>= 1, true, action).fork();
5041	>	}
5042	>	Object v;
5043	>	while ((v = advance()) != null)
5044	>	action.apply(entryFor((K)nextKey, (V)v));
5045	>	tryComplete();
5046	>	}
5047	>	}
5048	>
5049	>	@SuppressWarnings("serial")
5050	>	static final class ForEachMappingTask<K,V>
5051	>	extends BulkTask<K,V,Void> {
5052	>	final BiAction<K,V> action;
5053	>	ForEachMappingTask
5054	>	(ConcurrentHashMap<K,V> m,
5055	>	BiAction<K,V> action) {
5056	>	super(m);
5057	>	this.action = action;
5058	>	}
5059	>	ForEachMappingTask
5060	>	(BulkTask<K,V,?> p, int b, boolean split,
5061	>	BiAction<K,V> action) {
5062	>	super(p, b, split);
5063	>	this.action = action;
5064	>	}
5065	>
5066	>	@SuppressWarnings("unchecked") public final void compute() {
5067	>	final BiAction<K,V> action = this.action;
5068	>	if (action == null)
5069	>	throw new Error(NullFunctionMessage);
5070	>	int b = batch(), c;
5071	>	while (b > 1 && baseIndex != baseLimit) {
5072	>	do {} while (!casPending(c = pending, c+1));
5073	>	new ForEachMappingTask<K,V>(this, b >>>= 1, true,
5074	>	action).fork();
5075	>	}
5076	>	Object v;
5077	>	while ((v = advance()) != null)
5078	>	action.apply((K)nextKey, (V)v);
5079	>	tryComplete();
5080	>	}
5081	>	}
5082	>
5083	>	@SuppressWarnings("serial")
5084	>	static final class ForEachTransformedKeyTask<K,V,U>
5085	>	extends BulkTask<K,V,Void> {
5086	>	final Fun<? super K, ? extends U> transformer;
5087	>	final Action<U> action;
5088	>	ForEachTransformedKeyTask
5089	>	(ConcurrentHashMap<K,V> m,
5090	>	Fun<? super K, ? extends U> transformer,
5091	>	Action<U> action) {
5092	>	super(m);
5093	>	this.transformer = transformer;
5094	>	this.action = action;
5095	>
5096	>	}
5097	>	ForEachTransformedKeyTask
5098	>	(BulkTask<K,V,?> p, int b, boolean split,
5099	>	Fun<? super K, ? extends U> transformer,
5100	>	Action<U> action) {
5101	>	super(p, b, split);
5102	>	this.transformer = transformer;
5103	>	this.action = action;
5104	>	}
5105	>	@SuppressWarnings("unchecked") public final void compute() {
5106	>	final Fun<? super K, ? extends U> transformer =
5107	>	this.transformer;
5108	>	final Action<U> action = this.action;
5109	>	if (transformer == null || action == null)
5110	>	throw new Error(NullFunctionMessage);
5111	>	int b = batch(), c;
5112	>	while (b > 1 && baseIndex != baseLimit) {
5113	>	do {} while (!casPending(c = pending, c+1));
5114	>	new ForEachTransformedKeyTask<K,V,U>
5115	>	(this, b >>>= 1, true, transformer, action).fork();
5116	>	}
5117	>	U u;
5118	>	while (advance() != null) {
5119	>	if ((u = transformer.apply((K)nextKey)) != null)
5120	>	action.apply(u);
5121	>	}
5122	>	tryComplete();
5123	>	}
5124	>	}
5125	>
5126	>	@SuppressWarnings("serial")
5127	>	static final class ForEachTransformedValueTask<K,V,U>
5128	>	extends BulkTask<K,V,Void> {
5129	>	final Fun<? super V, ? extends U> transformer;
5130	>	final Action<U> action;
5131	>	ForEachTransformedValueTask
5132	>	(ConcurrentHashMap<K,V> m,
5133	>	Fun<? super V, ? extends U> transformer,
5134	>	Action<U> action) {
5135	>	super(m);
5136	>	this.transformer = transformer;
5137	>	this.action = action;
5138	>
5139	>	}
5140	>	ForEachTransformedValueTask
5141	>	(BulkTask<K,V,?> p, int b, boolean split,
5142	>	Fun<? super V, ? extends U> transformer,
5143	>	Action<U> action) {
5144	>	super(p, b, split);
5145	>	this.transformer = transformer;
5146	>	this.action = action;
5147	>	}
5148	>	@SuppressWarnings("unchecked") public final void compute() {
5149	>	final Fun<? super V, ? extends U> transformer =
5150	>	this.transformer;
5151	>	final Action<U> action = this.action;
5152	>	if (transformer == null || action == null)
5153	>	throw new Error(NullFunctionMessage);
5154	>	int b = batch(), c;
5155	>	while (b > 1 && baseIndex != baseLimit) {
5156	>	do {} while (!casPending(c = pending, c+1));
5157	>	new ForEachTransformedValueTask<K,V,U>
5158	>	(this, b >>>= 1, true, transformer, action).fork();
5159	>	}
5160	>	Object v; U u;
5161	>	while ((v = advance()) != null) {
5162	>	if ((u = transformer.apply((V)v)) != null)
5163	>	action.apply(u);
5164	>	}
5165	>	tryComplete();
5166	>	}
5167	>	}
5168	>
5169	>	@SuppressWarnings("serial")
5170	>	static final class ForEachTransformedEntryTask<K,V,U>
5171	>	extends BulkTask<K,V,Void> {
5172	>	final Fun<Map.Entry<K,V>, ? extends U> transformer;
5173	>	final Action<U> action;
5174	>	ForEachTransformedEntryTask
5175	>	(ConcurrentHashMap<K,V> m,
5176	>	Fun<Map.Entry<K,V>, ? extends U> transformer,
5177	>	Action<U> action) {
5178	>	super(m);
5179	>	this.transformer = transformer;
5180	>	this.action = action;
5181	>
5182	>	}
5183	>	ForEachTransformedEntryTask
5184	>	(BulkTask<K,V,?> p, int b, boolean split,
5185	>	Fun<Map.Entry<K,V>, ? extends U> transformer,
5186	>	Action<U> action) {
5187	>	super(p, b, split);
5188	>	this.transformer = transformer;
5189	>	this.action = action;
5190	>	}
5191	>	@SuppressWarnings("unchecked") public final void compute() {
5192	>	final Fun<Map.Entry<K,V>, ? extends U> transformer =
5193	>	this.transformer;
5194	>	final Action<U> action = this.action;
5195	>	if (transformer == null || action == null)
5196	>	throw new Error(NullFunctionMessage);
5197	>	int b = batch(), c;
5198	>	while (b > 1 && baseIndex != baseLimit) {
5199	>	do {} while (!casPending(c = pending, c+1));
5200	>	new ForEachTransformedEntryTask<K,V,U>
5201	>	(this, b >>>= 1, true, transformer, action).fork();
5202	>	}
5203	>	Object v; U u;
5204	>	while ((v = advance()) != null) {
5205	>	if ((u = transformer.apply(entryFor((K)nextKey, (V)v))) != null)
5206	>	action.apply(u);
5207	>	}
5208	>	tryComplete();
5209	>	}
5210	>	}
5211	>
5212	>	@SuppressWarnings("serial")
5213	>	static final class ForEachTransformedMappingTask<K,V,U>
5214	>	extends BulkTask<K,V,Void> {
5215	>	final BiFun<? super K, ? super V, ? extends U> transformer;
5216	>	final Action<U> action;
5217	>	ForEachTransformedMappingTask
5218	>	(ConcurrentHashMap<K,V> m,
5219	>	BiFun<? super K, ? super V, ? extends U> transformer,
5220	>	Action<U> action) {
5221	>	super(m);
5222	>	this.transformer = transformer;
5223	>	this.action = action;
5224	>
5225	>	}
5226	>	ForEachTransformedMappingTask
5227	>	(BulkTask<K,V,?> p, int b, boolean split,
5228	>	BiFun<? super K, ? super V, ? extends U> transformer,
5229	>	Action<U> action) {
5230	>	super(p, b, split);
5231	>	this.transformer = transformer;
5232	>	this.action = action;
5233	>	}
5234	>	@SuppressWarnings("unchecked") public final void compute() {
5235	>	final BiFun<? super K, ? super V, ? extends U> transformer =
5236	>	this.transformer;
5237	>	final Action<U> action = this.action;
5238	>	if (transformer == null || action == null)
5239	>	throw new Error(NullFunctionMessage);
5240	>	int b = batch(), c;
5241	>	while (b > 1 && baseIndex != baseLimit) {
5242	>	do {} while (!casPending(c = pending, c+1));
5243	>	new ForEachTransformedMappingTask<K,V,U>
5244	>	(this, b >>>= 1, true, transformer, action).fork();
5245	>	}
5246	>	Object v; U u;
5247	>	while ((v = advance()) != null) {
5248	>	if ((u = transformer.apply((K)nextKey, (V)v)) != null)
5249	>	action.apply(u);
5250	>	}
5251	>	tryComplete();
5252	>	}
5253	>	}
5254	>
5255	>	@SuppressWarnings("serial")
5256	>	static final class SearchKeysTask<K,V,U>
5257	>	extends BulkTask<K,V,U> {
5258	>	final Fun<? super K, ? extends U> searchFunction;
5259	>	final AtomicReference<U> result;
5260	>	SearchKeysTask
5261	>	(ConcurrentHashMap<K,V> m,
5262	>	Fun<? super K, ? extends U> searchFunction,
5263	>	AtomicReference<U> result) {
5264	>	super(m);
5265	>	this.searchFunction = searchFunction; this.result = result;
5266	>	}
5267	>	SearchKeysTask
5268	>	(BulkTask<K,V,?> p, int b, boolean split,
5269	>	Fun<? super K, ? extends U> searchFunction,
5270	>	AtomicReference<U> result) {
5271	>	super(p, b, split);
5272	>	this.searchFunction = searchFunction; this.result = result;
5273	>	}
5274	>	@SuppressWarnings("unchecked") public final void compute() {
5275	>	AtomicReference<U> result = this.result;
5276	>	final Fun<? super K, ? extends U> searchFunction =
5277	>	this.searchFunction;
5278	>	if (searchFunction == null || result == null)
5279	>	throw new Error(NullFunctionMessage);
5280	>	int b = batch(), c;
5281	>	while (b > 1 && baseIndex != baseLimit && result.get() == null) {
5282	>	do {} while (!casPending(c = pending, c+1));
5283	>	new SearchKeysTask<K,V,U>(this, b >>>= 1, true,
5284	>	searchFunction, result).fork();
5285	>	}
5286	>	U u;
5287	>	while (result.get() == null && advance() != null) {
5288	>	if ((u = searchFunction.apply((K)nextKey)) != null) {
5289	>	if (result.compareAndSet(null, u)) {
5290	>	for (BulkTask<K,V,?> a = this, p;;) {
5291	>	if ((p = a.parent) == null) {
5292	>	a.quietlyComplete();
5293	>	break;
5294	>	}
5295	>	a = p;
5296	>	}
5297	>	}
5298	>	break;
5299	>	}
5300	>	}
5301	>	tryComplete();
5302	>	}
5303	>	public final U getRawResult() { return result.get(); }
5304	>	}
5305	>
5306	>	@SuppressWarnings("serial")
5307	>	static final class SearchValuesTask<K,V,U>
5308	>	extends BulkTask<K,V,U> {
5309	>	final Fun<? super V, ? extends U> searchFunction;
5310	>	final AtomicReference<U> result;
5311	>	SearchValuesTask
5312	>	(ConcurrentHashMap<K,V> m,
5313	>	Fun<? super V, ? extends U> searchFunction,
5314	>	AtomicReference<U> result) {
5315	>	super(m);
5316	>	this.searchFunction = searchFunction; this.result = result;
5317	>	}
5318	>	SearchValuesTask
5319	>	(BulkTask<K,V,?> p, int b, boolean split,
5320	>	Fun<? super V, ? extends U> searchFunction,
5321	>	AtomicReference<U> result) {
5322	>	super(p, b, split);
5323	>	this.searchFunction = searchFunction; this.result = result;
5324	>	}
5325	>	@SuppressWarnings("unchecked") public final void compute() {
5326	>	AtomicReference<U> result = this.result;
5327	>	final Fun<? super V, ? extends U> searchFunction =
5328	>	this.searchFunction;
5329	>	if (searchFunction == null || result == null)
5330	>	throw new Error(NullFunctionMessage);
5331	>	int b = batch(), c;
5332	>	while (b > 1 && baseIndex != baseLimit && result.get() == null) {
5333	>	do {} while (!casPending(c = pending, c+1));
5334	>	new SearchValuesTask<K,V,U>(this, b >>>= 1, true,
5335	>	searchFunction, result).fork();
5336	>	}
5337	>	Object v; U u;
5338	>	while (result.get() == null && (v = advance()) != null) {
5339	>	if ((u = searchFunction.apply((V)v)) != null) {
5340	>	if (result.compareAndSet(null, u)) {
5341	>	for (BulkTask<K,V,?> a = this, p;;) {
5342	>	if ((p = a.parent) == null) {
5343	>	a.quietlyComplete();
5344	>	break;
5345	>	}
5346	>	a = p;
5347	>	}
5348	>	}
5349	>	break;
5350	>	}
5351	>	}
5352	>	tryComplete();
5353	>	}
5354	>	public final U getRawResult() { return result.get(); }
5355	>	}
5356	>
5357	>	@SuppressWarnings("serial")
5358	>	static final class SearchEntriesTask<K,V,U>
5359	>	extends BulkTask<K,V,U> {
5360	>	final Fun<Entry<K,V>, ? extends U> searchFunction;
5361	>	final AtomicReference<U> result;
5362	>	SearchEntriesTask
5363	>	(ConcurrentHashMap<K,V> m,
5364	>	Fun<Entry<K,V>, ? extends U> searchFunction,
5365	>	AtomicReference<U> result) {
5366	>	super(m);
5367	>	this.searchFunction = searchFunction; this.result = result;
5368	>	}
5369	>	SearchEntriesTask
5370	>	(BulkTask<K,V,?> p, int b, boolean split,
5371	>	Fun<Entry<K,V>, ? extends U> searchFunction,
5372	>	AtomicReference<U> result) {
5373	>	super(p, b, split);
5374	>	this.searchFunction = searchFunction; this.result = result;
5375	>	}
5376	>	@SuppressWarnings("unchecked") public final void compute() {
5377	>	AtomicReference<U> result = this.result;
5378	>	final Fun<Entry<K,V>, ? extends U> searchFunction =
5379	>	this.searchFunction;
5380	>	if (searchFunction == null || result == null)
5381	>	throw new Error(NullFunctionMessage);
5382	>	int b = batch(), c;
5383	>	while (b > 1 && baseIndex != baseLimit && result.get() == null) {
5384	>	do {} while (!casPending(c = pending, c+1));
5385	>	new SearchEntriesTask<K,V,U>(this, b >>>= 1, true,
5386	>	searchFunction, result).fork();
5387	>	}
5388	>	Object v; U u;
5389	>	while (result.get() == null && (v = advance()) != null) {
5390	>	if ((u = searchFunction.apply(entryFor((K)nextKey, (V)v))) != null) {
5391	>	if (result.compareAndSet(null, u)) {
5392	>	for (BulkTask<K,V,?> a = this, p;;) {
5393	>	if ((p = a.parent) == null) {
5394	>	a.quietlyComplete();
5395	>	break;
5396	>	}
5397	>	a = p;
5398	>	}
5399	>	}
5400	>	break;
5401	>	}
5402	>	}
5403	>	tryComplete();
5404	>	}
5405	>	public final U getRawResult() { return result.get(); }
5406	>	}
5407	>
5408	>	@SuppressWarnings("serial")
5409	>	static final class SearchMappingsTask<K,V,U>
5410	>	extends BulkTask<K,V,U> {
5411	>	final BiFun<? super K, ? super V, ? extends U> searchFunction;
5412	>	final AtomicReference<U> result;
5413	>	SearchMappingsTask
5414	>	(ConcurrentHashMap<K,V> m,
5415	>	BiFun<? super K, ? super V, ? extends U> searchFunction,
5416	>	AtomicReference<U> result) {
5417	>	super(m);
5418	>	this.searchFunction = searchFunction; this.result = result;
5419	>	}
5420	>	SearchMappingsTask
5421	>	(BulkTask<K,V,?> p, int b, boolean split,
5422	>	BiFun<? super K, ? super V, ? extends U> searchFunction,
5423	>	AtomicReference<U> result) {
5424	>	super(p, b, split);
5425	>	this.searchFunction = searchFunction; this.result = result;
5426	>	}
5427	>	@SuppressWarnings("unchecked") public final void compute() {
5428	>	AtomicReference<U> result = this.result;
5429	>	final BiFun<? super K, ? super V, ? extends U> searchFunction =
5430	>	this.searchFunction;
5431	>	if (searchFunction == null || result == null)
5432	>	throw new Error(NullFunctionMessage);
5433	>	int b = batch(), c;
5434	>	while (b > 1 && baseIndex != baseLimit && result.get() == null) {
5435	>	do {} while (!casPending(c = pending, c+1));
5436	>	new SearchMappingsTask<K,V,U>(this, b >>>= 1, true,
5437	>	searchFunction, result).fork();
5438	>	}
5439	>	Object v; U u;
5440	>	while (result.get() == null && (v = advance()) != null) {
5441	>	if ((u = searchFunction.apply((K)nextKey, (V)v)) != null) {
5442	>	if (result.compareAndSet(null, u)) {
5443	>	for (BulkTask<K,V,?> a = this, p;;) {
5444	>	if ((p = a.parent) == null) {
5445	>	a.quietlyComplete();
5446	>	break;
5447	>	}
5448	>	a = p;
5449	>	}
5450	>	}
5451	>	break;
5452	>	}
5453	>	}
5454	>	tryComplete();
5455	>	}
5456	>	public final U getRawResult() { return result.get(); }
5457	>	}
5458	>
5459	>	@SuppressWarnings("serial")
5460	>	static final class ReduceKeysTask<K,V>
5461	>	extends BulkTask<K,V,K> {
5462	>	final BiFun<? super K, ? super K, ? extends K> reducer;
5463	>	K result;
5464	>	ReduceKeysTask<K,V> sibling;
5465	>	ReduceKeysTask
5466	>	(ConcurrentHashMap<K,V> m,
5467	>	BiFun<? super K, ? super K, ? extends K> reducer) {
5468	>	super(m);
5469	>	this.reducer = reducer;
5470	>	}
5471	>	ReduceKeysTask
5472	>	(BulkTask<K,V,?> p, int b, boolean split,
5473	>	BiFun<? super K, ? super K, ? extends K> reducer) {
5474	>	super(p, b, split);
5475	>	this.reducer = reducer;
5476	>	}
5477	>
5478	>	@SuppressWarnings("unchecked") public final void compute() {
5479	>	ReduceKeysTask<K,V> t = this;
5480	>	final BiFun<? super K, ? super K, ? extends K> reducer =
5481	>	this.reducer;
5482	>	if (reducer == null)
5483	>	throw new Error(NullFunctionMessage);
5484	>	int b = batch();
5485	>	while (b > 1 && t.baseIndex != t.baseLimit) {
5486	>	b >>>= 1;
5487	>	t.pending = 1;
5488	>	ReduceKeysTask<K,V> rt =
5489	>	new ReduceKeysTask<K,V>
5490	>	(t, b, true, reducer);
5491	>	t = new ReduceKeysTask<K,V>
5492	>	(t, b, false, reducer);
5493	>	t.sibling = rt;
5494	>	rt.sibling = t;
5495	>	rt.fork();
5496	>	}
5497	>	K r = null;
5498	>	while (t.advance() != null) {
5499	>	K u = (K)t.nextKey;
5500	>	r = (r == null) ? u : reducer.apply(r, u);
5501	>	}
5502	>	t.result = r;
5503	>	for (;;) {
5504	>	int c; BulkTask<K,V,?> par; ReduceKeysTask<K,V> s, p; K u;
5505	>	if ((par = t.parent) == null ||
5506	>	!(par instanceof ReduceKeysTask)) {
5507	>	t.quietlyComplete();
5508	>	break;
5509	>	}
5510	>	else if ((c = (p = (ReduceKeysTask<K,V>)par).pending) == 0) {
5511	>	if ((s = t.sibling) != null && (u = s.result) != null)
5512	>	r = (r == null) ? u : reducer.apply(r, u);
5513	>	(t = p).result = r;
5514	>	}
5515	>	else if (p.casPending(c, 0))
5516	>	break;
5517	>	}
5518	>	}
5519	>	public final K getRawResult() { return result; }
5520	>	}
5521	>
5522	>	@SuppressWarnings("serial")
5523	>	static final class ReduceValuesTask<K,V>
5524	>	extends BulkTask<K,V,V> {
5525	>	final BiFun<? super V, ? super V, ? extends V> reducer;
5526	>	V result;
5527	>	ReduceValuesTask<K,V> sibling;
5528	>	ReduceValuesTask
5529	>	(ConcurrentHashMap<K,V> m,
5530	>	BiFun<? super V, ? super V, ? extends V> reducer) {
5531	>	super(m);
5532	>	this.reducer = reducer;
5533	>	}
5534	>	ReduceValuesTask
5535	>	(BulkTask<K,V,?> p, int b, boolean split,
5536	>	BiFun<? super V, ? super V, ? extends V> reducer) {
5537	>	super(p, b, split);
5538	>	this.reducer = reducer;
5539	>	}
5540	>
5541	>	@SuppressWarnings("unchecked") public final void compute() {
5542	>	ReduceValuesTask<K,V> t = this;
5543	>	final BiFun<? super V, ? super V, ? extends V> reducer =
5544	>	this.reducer;
5545	>	if (reducer == null)
5546	>	throw new Error(NullFunctionMessage);
5547	>	int b = batch();
5548	>	while (b > 1 && t.baseIndex != t.baseLimit) {
5549	>	b >>>= 1;
5550	>	t.pending = 1;
5551	>	ReduceValuesTask<K,V> rt =
5552	>	new ReduceValuesTask<K,V>
5553	>	(t, b, true, reducer);
5554	>	t = new ReduceValuesTask<K,V>
5555	>	(t, b, false, reducer);
5556	>	t.sibling = rt;
5557	>	rt.sibling = t;
5558	>	rt.fork();
5559	>	}
5560	>	V r = null;
5561	>	Object v;
5562	>	while ((v = t.advance()) != null) {
5563	>	V u = (V)v;
5564	>	r = (r == null) ? u : reducer.apply(r, u);
5565	>	}
5566	>	t.result = r;
5567	>	for (;;) {
5568	>	int c; BulkTask<K,V,?> par; ReduceValuesTask<K,V> s, p; V u;
5569	>	if ((par = t.parent) == null ||
5570	>	!(par instanceof ReduceValuesTask)) {
5571	>	t.quietlyComplete();
5572	>	break;
5573	>	}
5574	>	else if ((c = (p = (ReduceValuesTask<K,V>)par).pending) == 0) {
5575	>	if ((s = t.sibling) != null && (u = s.result) != null)
5576	>	r = (r == null) ? u : reducer.apply(r, u);
5577	>	(t = p).result = r;
5578	>	}
5579	>	else if (p.casPending(c, 0))
5580	>	break;
5581	>	}
5582	>	}
5583	>	public final V getRawResult() { return result; }
5584	>	}
5585	>
5586	>	@SuppressWarnings("serial")
5587	>	static final class ReduceEntriesTask<K,V>
5588	>	extends BulkTask<K,V,Map.Entry<K,V>> {
5589	>	final BiFun<Map.Entry<K,V>, Map.Entry<K,V>, ? extends Map.Entry<K,V>> reducer;
5590	>	Map.Entry<K,V> result;
5591	>	ReduceEntriesTask<K,V> sibling;
5592	>	ReduceEntriesTask
5593	>	(ConcurrentHashMap<K,V> m,
5594	>	BiFun<Entry<K,V>, Map.Entry<K,V>, ? extends Map.Entry<K,V>> reducer) {
5595	>	super(m);
5596	>	this.reducer = reducer;
5597	>	}
5598	>	ReduceEntriesTask
5599	>	(BulkTask<K,V,?> p, int b, boolean split,
5600	>	BiFun<Map.Entry<K,V>, Map.Entry<K,V>, ? extends Map.Entry<K,V>> reducer) {
5601	>	super(p, b, split);
5602	>	this.reducer = reducer;
5603	>	}
5604	>
5605	>	@SuppressWarnings("unchecked") public final void compute() {
5606	>	ReduceEntriesTask<K,V> t = this;
5607	>	final BiFun<Map.Entry<K,V>, Map.Entry<K,V>, ? extends Map.Entry<K,V>> reducer =
5608	>	this.reducer;
5609	>	if (reducer == null)
5610	>	throw new Error(NullFunctionMessage);
5611	>	int b = batch();
5612	>	while (b > 1 && t.baseIndex != t.baseLimit) {
5613	>	b >>>= 1;
5614	>	t.pending = 1;
5615	>	ReduceEntriesTask<K,V> rt =
5616	>	new ReduceEntriesTask<K,V>
5617	>	(t, b, true, reducer);
5618	>	t = new ReduceEntriesTask<K,V>
5619	>	(t, b, false, reducer);
5620	>	t.sibling = rt;
5621	>	rt.sibling = t;
5622	>	rt.fork();
5623	>	}
5624	>	Map.Entry<K,V> r = null;
5625	>	Object v;
5626	>	while ((v = t.advance()) != null) {
5627	>	Map.Entry<K,V> u = entryFor((K)t.nextKey, (V)v);
5628	>	r = (r == null) ? u : reducer.apply(r, u);
5629	>	}
5630	>	t.result = r;
5631	>	for (;;) {
5632	>	int c; BulkTask<K,V,?> par; ReduceEntriesTask<K,V> s, p;
5633	>	Map.Entry<K,V> u;
5634	>	if ((par = t.parent) == null ||
5635	>	!(par instanceof ReduceEntriesTask)) {
5636	>	t.quietlyComplete();
5637	>	break;
5638	>	}
5639	>	else if ((c = (p = (ReduceEntriesTask<K,V>)par).pending) == 0) {
5640	>	if ((s = t.sibling) != null && (u = s.result) != null)
5641	>	r = (r == null) ? u : reducer.apply(r, u);
5642	>	(t = p).result = r;
5643	>	}
5644	>	else if (p.casPending(c, 0))
5645	>	break;
5646	>	}
5647	>	}
5648	>	public final Map.Entry<K,V> getRawResult() { return result; }
5649	>	}
5650	>
5651	>	@SuppressWarnings("serial")
5652	>	static final class MapReduceKeysTask<K,V,U>
5653	>	extends BulkTask<K,V,U> {
5654	>	final Fun<? super K, ? extends U> transformer;
5655	>	final BiFun<? super U, ? super U, ? extends U> reducer;
5656	>	U result;
5657	>	MapReduceKeysTask<K,V,U> sibling;
5658	>	MapReduceKeysTask
5659	>	(ConcurrentHashMap<K,V> m,
5660	>	Fun<? super K, ? extends U> transformer,
5661	>	BiFun<? super U, ? super U, ? extends U> reducer) {
5662	>	super(m);
5663	>	this.transformer = transformer;
5664	>	this.reducer = reducer;
5665	>	}
5666	>	MapReduceKeysTask
5667	>	(BulkTask<K,V,?> p, int b, boolean split,
5668	>	Fun<? super K, ? extends U> transformer,
5669	>	BiFun<? super U, ? super U, ? extends U> reducer) {
5670	>	super(p, b, split);
5671	>	this.transformer = transformer;
5672	>	this.reducer = reducer;
5673	>	}
5674	>	@SuppressWarnings("unchecked") public final void compute() {
5675	>	MapReduceKeysTask<K,V,U> t = this;
5676	>	final Fun<? super K, ? extends U> transformer =
5677	>	this.transformer;
5678	>	final BiFun<? super U, ? super U, ? extends U> reducer =
5679	>	this.reducer;
5680	>	if (transformer == null || reducer == null)
5681	>	throw new Error(NullFunctionMessage);
5682	>	int b = batch();
5683	>	while (b > 1 && t.baseIndex != t.baseLimit) {
5684	>	b >>>= 1;
5685	>	t.pending = 1;
5686	>	MapReduceKeysTask<K,V,U> rt =
5687	>	new MapReduceKeysTask<K,V,U>
5688	>	(t, b, true, transformer, reducer);
5689	>	t = new MapReduceKeysTask<K,V,U>
5690	>	(t, b, false, transformer, reducer);
5691	>	t.sibling = rt;
5692	>	rt.sibling = t;
5693	>	rt.fork();
5694	>	}
5695	>	U r = null, u;
5696	>	while (t.advance() != null) {
5697	>	if ((u = transformer.apply((K)t.nextKey)) != null)
5698	>	r = (r == null) ? u : reducer.apply(r, u);
5699	>	}
5700	>	t.result = r;
5701	>	for (;;) {
5702	>	int c; BulkTask<K,V,?> par; MapReduceKeysTask<K,V,U> s, p;
5703	>	if ((par = t.parent) == null ||
5704	>	!(par instanceof MapReduceKeysTask)) {
5705	>	t.quietlyComplete();
5706	>	break;
5707	>	}
5708	>	else if ((c = (p = (MapReduceKeysTask<K,V,U>)par).pending) == 0) {
5709	>	if ((s = t.sibling) != null && (u = s.result) != null)
5710	>	r = (r == null) ? u : reducer.apply(r, u);
5711	>	(t = p).result = r;
5712	>	}
5713	>	else if (p.casPending(c, 0))
5714	>	break;
5715	>	}
5716		}
5717	+	public final U getRawResult() { return result; }
5718		}
5719
5720	+	@SuppressWarnings("serial")
5721	+	static final class MapReduceValuesTask<K,V,U>
5722	+	extends BulkTask<K,V,U> {
5723	+	final Fun<? super V, ? extends U> transformer;
5724	+	final BiFun<? super U, ? super U, ? extends U> reducer;
5725	+	U result;
5726	+	MapReduceValuesTask<K,V,U> sibling;
5727	+	MapReduceValuesTask
5728	+	(ConcurrentHashMap<K,V> m,
5729	+	Fun<? super V, ? extends U> transformer,
5730	+	BiFun<? super U, ? super U, ? extends U> reducer) {
5731	+	super(m);
5732	+	this.transformer = transformer;
5733	+	this.reducer = reducer;
5734	+	}
5735	+	MapReduceValuesTask
5736	+	(BulkTask<K,V,?> p, int b, boolean split,
5737	+	Fun<? super V, ? extends U> transformer,
5738	+	BiFun<? super U, ? super U, ? extends U> reducer) {
5739	+	super(p, b, split);
5740	+	this.transformer = transformer;
5741	+	this.reducer = reducer;
5742	+	}
5743	+	@SuppressWarnings("unchecked") public final void compute() {
5744	+	MapReduceValuesTask<K,V,U> t = this;
5745	+	final Fun<? super V, ? extends U> transformer =
5746	+	this.transformer;
5747	+	final BiFun<? super U, ? super U, ? extends U> reducer =
5748	+	this.reducer;
5749	+	if (transformer == null || reducer == null)
5750	+	throw new Error(NullFunctionMessage);
5751	+	int b = batch();
5752	+	while (b > 1 && t.baseIndex != t.baseLimit) {
5753	+	b >>>= 1;
5754	+	t.pending = 1;
5755	+	MapReduceValuesTask<K,V,U> rt =
5756	+	new MapReduceValuesTask<K,V,U>
5757	+	(t, b, true, transformer, reducer);
5758	+	t = new MapReduceValuesTask<K,V,U>
5759	+	(t, b, false, transformer, reducer);
5760	+	t.sibling = rt;
5761	+	rt.sibling = t;
5762	+	rt.fork();
5763	+	}
5764	+	U r = null, u;
5765	+	Object v;
5766	+	while ((v = t.advance()) != null) {
5767	+	if ((u = transformer.apply((V)v)) != null)
5768	+	r = (r == null) ? u : reducer.apply(r, u);
5769	+	}
5770	+	t.result = r;
5771	+	for (;;) {
5772	+	int c; BulkTask<K,V,?> par; MapReduceValuesTask<K,V,U> s, p;
5773	+	if ((par = t.parent) == null ||
5774	+	!(par instanceof MapReduceValuesTask)) {
5775	+	t.quietlyComplete();
5776	+	break;
5777	+	}
5778	+	else if ((c = (p = (MapReduceValuesTask<K,V,U>)par).pending) == 0) {
5779	+	if ((s = t.sibling) != null && (u = s.result) != null)
5780	+	r = (r == null) ? u : reducer.apply(r, u);
5781	+	(t = p).result = r;
5782	+	}
5783	+	else if (p.casPending(c, 0))
5784	+	break;
5785	+	}
5786	+	}
5787	+	public final U getRawResult() { return result; }
5788	+	}
5789	+
5790	+	@SuppressWarnings("serial")
5791	+	static final class MapReduceEntriesTask<K,V,U>
5792	+	extends BulkTask<K,V,U> {
5793	+	final Fun<Map.Entry<K,V>, ? extends U> transformer;
5794	+	final BiFun<? super U, ? super U, ? extends U> reducer;
5795	+	U result;
5796	+	MapReduceEntriesTask<K,V,U> sibling;
5797	+	MapReduceEntriesTask
5798	+	(ConcurrentHashMap<K,V> m,
5799	+	Fun<Map.Entry<K,V>, ? extends U> transformer,
5800	+	BiFun<? super U, ? super U, ? extends U> reducer) {
5801	+	super(m);
5802	+	this.transformer = transformer;
5803	+	this.reducer = reducer;
5804	+	}
5805	+	MapReduceEntriesTask
5806	+	(BulkTask<K,V,?> p, int b, boolean split,
5807	+	Fun<Map.Entry<K,V>, ? extends U> transformer,
5808	+	BiFun<? super U, ? super U, ? extends U> reducer) {
5809	+	super(p, b, split);
5810	+	this.transformer = transformer;
5811	+	this.reducer = reducer;
5812	+	}
5813	+	@SuppressWarnings("unchecked") public final void compute() {
5814	+	MapReduceEntriesTask<K,V,U> t = this;
5815	+	final Fun<Map.Entry<K,V>, ? extends U> transformer =
5816	+	this.transformer;
5817	+	final BiFun<? super U, ? super U, ? extends U> reducer =
5818	+	this.reducer;
5819	+	if (transformer == null || reducer == null)
5820	+	throw new Error(NullFunctionMessage);
5821	+	int b = batch();
5822	+	while (b > 1 && t.baseIndex != t.baseLimit) {
5823	+	b >>>= 1;
5824	+	t.pending = 1;
5825	+	MapReduceEntriesTask<K,V,U> rt =
5826	+	new MapReduceEntriesTask<K,V,U>
5827	+	(t, b, true, transformer, reducer);
5828	+	t = new MapReduceEntriesTask<K,V,U>
5829	+	(t, b, false, transformer, reducer);
5830	+	t.sibling = rt;
5831	+	rt.sibling = t;
5832	+	rt.fork();
5833	+	}
5834	+	U r = null, u;
5835	+	Object v;
5836	+	while ((v = t.advance()) != null) {
5837	+	if ((u = transformer.apply(entryFor((K)t.nextKey, (V)v))) != null)
5838	+	r = (r == null) ? u : reducer.apply(r, u);
5839	+	}
5840	+	t.result = r;
5841	+	for (;;) {
5842	+	int c; BulkTask<K,V,?> par; MapReduceEntriesTask<K,V,U> s, p;
5843	+	if ((par = t.parent) == null ||
5844	+	!(par instanceof MapReduceEntriesTask)) {
5845	+	t.quietlyComplete();
5846	+	break;
5847	+	}
5848	+	else if ((c = (p = (MapReduceEntriesTask<K,V,U>)par).pending) == 0) {
5849	+	if ((s = t.sibling) != null && (u = s.result) != null)
5850	+	r = (r == null) ? u : reducer.apply(r, u);
5851	+	(t = p).result = r;
5852	+	}
5853	+	else if (p.casPending(c, 0))
5854	+	break;
5855	+	}
5856	+	}
5857	+	public final U getRawResult() { return result; }
5858	+	}
5859	+
5860	+	@SuppressWarnings("serial")
5861	+	static final class MapReduceMappingsTask<K,V,U>
5862	+	extends BulkTask<K,V,U> {
5863	+	final BiFun<? super K, ? super V, ? extends U> transformer;
5864	+	final BiFun<? super U, ? super U, ? extends U> reducer;
5865	+	U result;
5866	+	MapReduceMappingsTask<K,V,U> sibling;
5867	+	MapReduceMappingsTask
5868	+	(ConcurrentHashMap<K,V> m,
5869	+	BiFun<? super K, ? super V, ? extends U> transformer,
5870	+	BiFun<? super U, ? super U, ? extends U> reducer) {
5871	+	super(m);
5872	+	this.transformer = transformer;
5873	+	this.reducer = reducer;
5874	+	}
5875	+	MapReduceMappingsTask
5876	+	(BulkTask<K,V,?> p, int b, boolean split,
5877	+	BiFun<? super K, ? super V, ? extends U> transformer,
5878	+	BiFun<? super U, ? super U, ? extends U> reducer) {
5879	+	super(p, b, split);
5880	+	this.transformer = transformer;
5881	+	this.reducer = reducer;
5882	+	}
5883	+	@SuppressWarnings("unchecked") public final void compute() {
5884	+	MapReduceMappingsTask<K,V,U> t = this;
5885	+	final BiFun<? super K, ? super V, ? extends U> transformer =
5886	+	this.transformer;
5887	+	final BiFun<? super U, ? super U, ? extends U> reducer =
5888	+	this.reducer;
5889	+	if (transformer == null || reducer == null)
5890	+	throw new Error(NullFunctionMessage);
5891	+	int b = batch();
5892	+	while (b > 1 && t.baseIndex != t.baseLimit) {
5893	+	b >>>= 1;
5894	+	t.pending = 1;
5895	+	MapReduceMappingsTask<K,V,U> rt =
5896	+	new MapReduceMappingsTask<K,V,U>
5897	+	(t, b, true, transformer, reducer);
5898	+	t = new MapReduceMappingsTask<K,V,U>
5899	+	(t, b, false, transformer, reducer);
5900	+	t.sibling = rt;
5901	+	rt.sibling = t;
5902	+	rt.fork();
5903	+	}
5904	+	U r = null, u;
5905	+	Object v;
5906	+	while ((v = t.advance()) != null) {
5907	+	if ((u = transformer.apply((K)t.nextKey, (V)v)) != null)
5908	+	r = (r == null) ? u : reducer.apply(r, u);
5909	+	}
5910	+	for (;;) {
5911	+	int c; BulkTask<K,V,?> par; MapReduceMappingsTask<K,V,U> s, p;
5912	+	if ((par = t.parent) == null ||
5913	+	!(par instanceof MapReduceMappingsTask)) {
5914	+	t.quietlyComplete();
5915	+	break;
5916	+	}
5917	+	else if ((c = (p = (MapReduceMappingsTask<K,V,U>)par).pending) == 0) {
5918	+	if ((s = t.sibling) != null && (u = s.result) != null)
5919	+	r = (r == null) ? u : reducer.apply(r, u);
5920	+	(t = p).result = r;
5921	+	}
5922	+	else if (p.casPending(c, 0))
5923	+	break;
5924	+	}
5925	+	}
5926	+	public final U getRawResult() { return result; }
5927	+	}
5928	+
5929	+	@SuppressWarnings("serial")
5930	+	static final class MapReduceKeysToDoubleTask<K,V>
5931	+	extends BulkTask<K,V,Double> {
5932	+	final ObjectToDouble<? super K> transformer;
5933	+	final DoubleByDoubleToDouble reducer;
5934	+	final double basis;
5935	+	double result;
5936	+	MapReduceKeysToDoubleTask<K,V> sibling;
5937	+	MapReduceKeysToDoubleTask
5938	+	(ConcurrentHashMap<K,V> m,
5939	+	ObjectToDouble<? super K> transformer,
5940	+	double basis,
5941	+	DoubleByDoubleToDouble reducer) {
5942	+	super(m);
5943	+	this.transformer = transformer;
5944	+	this.basis = basis; this.reducer = reducer;
5945	+	}
5946	+	MapReduceKeysToDoubleTask
5947	+	(BulkTask<K,V,?> p, int b, boolean split,
5948	+	ObjectToDouble<? super K> transformer,
5949	+	double basis,
5950	+	DoubleByDoubleToDouble reducer) {
5951	+	super(p, b, split);
5952	+	this.transformer = transformer;
5953	+	this.basis = basis; this.reducer = reducer;
5954	+	}
5955	+	@SuppressWarnings("unchecked") public final void compute() {
5956	+	MapReduceKeysToDoubleTask<K,V> t = this;
5957	+	final ObjectToDouble<? super K> transformer =
5958	+	this.transformer;
5959	+	final DoubleByDoubleToDouble reducer = this.reducer;
5960	+	if (transformer == null || reducer == null)
5961	+	throw new Error(NullFunctionMessage);
5962	+	final double id = this.basis;
5963	+	int b = batch();
5964	+	while (b > 1 && t.baseIndex != t.baseLimit) {
5965	+	b >>>= 1;
5966	+	t.pending = 1;
5967	+	MapReduceKeysToDoubleTask<K,V> rt =
5968	+	new MapReduceKeysToDoubleTask<K,V>
5969	+	(t, b, true, transformer, id, reducer);
5970	+	t = new MapReduceKeysToDoubleTask<K,V>
5971	+	(t, b, false, transformer, id, reducer);
5972	+	t.sibling = rt;
5973	+	rt.sibling = t;
5974	+	rt.fork();
5975	+	}
5976	+	double r = id;
5977	+	while (t.advance() != null)
5978	+	r = reducer.apply(r, transformer.apply((K)t.nextKey));
5979	+	t.result = r;
5980	+	for (;;) {
5981	+	int c; BulkTask<K,V,?> par; MapReduceKeysToDoubleTask<K,V> s, p;
5982	+	if ((par = t.parent) == null ||
5983	+	!(par instanceof MapReduceKeysToDoubleTask)) {
5984	+	t.quietlyComplete();
5985	+	break;
5986	+	}
5987	+	else if ((c = (p = (MapReduceKeysToDoubleTask<K,V>)par).pending) == 0) {
5988	+	if ((s = t.sibling) != null)
5989	+	r = reducer.apply(r, s.result);
5990	+	(t = p).result = r;
5991	+	}
5992	+	else if (p.casPending(c, 0))
5993	+	break;
5994	+	}
5995	+	}
5996	+	public final Double getRawResult() { return result; }
5997	+	}
5998	+
5999	+	@SuppressWarnings("serial")
6000	+	static final class MapReduceValuesToDoubleTask<K,V>
6001	+	extends BulkTask<K,V,Double> {
6002	+	final ObjectToDouble<? super V> transformer;
6003	+	final DoubleByDoubleToDouble reducer;
6004	+	final double basis;
6005	+	double result;
6006	+	MapReduceValuesToDoubleTask<K,V> sibling;
6007	+	MapReduceValuesToDoubleTask
6008	+	(ConcurrentHashMap<K,V> m,
6009	+	ObjectToDouble<? super V> transformer,
6010	+	double basis,
6011	+	DoubleByDoubleToDouble reducer) {
6012	+	super(m);
6013	+	this.transformer = transformer;
6014	+	this.basis = basis; this.reducer = reducer;
6015	+	}
6016	+	MapReduceValuesToDoubleTask
6017	+	(BulkTask<K,V,?> p, int b, boolean split,
6018	+	ObjectToDouble<? super V> transformer,
6019	+	double basis,
6020	+	DoubleByDoubleToDouble reducer) {
6021	+	super(p, b, split);
6022	+	this.transformer = transformer;
6023	+	this.basis = basis; this.reducer = reducer;
6024	+	}
6025	+	@SuppressWarnings("unchecked") public final void compute() {
6026	+	MapReduceValuesToDoubleTask<K,V> t = this;
6027	+	final ObjectToDouble<? super V> transformer =
6028	+	this.transformer;
6029	+	final DoubleByDoubleToDouble reducer = this.reducer;
6030	+	if (transformer == null || reducer == null)
6031	+	throw new Error(NullFunctionMessage);
6032	+	final double id = this.basis;
6033	+	int b = batch();
6034	+	while (b > 1 && t.baseIndex != t.baseLimit) {
6035	+	b >>>= 1;
6036	+	t.pending = 1;
6037	+	MapReduceValuesToDoubleTask<K,V> rt =
6038	+	new MapReduceValuesToDoubleTask<K,V>
6039	+	(t, b, true, transformer, id, reducer);
6040	+	t = new MapReduceValuesToDoubleTask<K,V>
6041	+	(t, b, false, transformer, id, reducer);
6042	+	t.sibling = rt;
6043	+	rt.sibling = t;
6044	+	rt.fork();
6045	+	}
6046	+	double r = id;
6047	+	Object v;
6048	+	while ((v = t.advance()) != null)
6049	+	r = reducer.apply(r, transformer.apply((V)v));
6050	+	t.result = r;
6051	+	for (;;) {
6052	+	int c; BulkTask<K,V,?> par; MapReduceValuesToDoubleTask<K,V> s, p;
6053	+	if ((par = t.parent) == null ||
6054	+	!(par instanceof MapReduceValuesToDoubleTask)) {
6055	+	t.quietlyComplete();
6056	+	break;
6057	+	}
6058	+	else if ((c = (p = (MapReduceValuesToDoubleTask<K,V>)par).pending) == 0) {
6059	+	if ((s = t.sibling) != null)
6060	+	r = reducer.apply(r, s.result);
6061	+	(t = p).result = r;
6062	+	}
6063	+	else if (p.casPending(c, 0))
6064	+	break;
6065	+	}
6066	+	}
6067	+	public final Double getRawResult() { return result; }
6068	+	}
6069	+
6070	+	@SuppressWarnings("serial")
6071	+	static final class MapReduceEntriesToDoubleTask<K,V>
6072	+	extends BulkTask<K,V,Double> {
6073	+	final ObjectToDouble<Map.Entry<K,V>> transformer;
6074	+	final DoubleByDoubleToDouble reducer;
6075	+	final double basis;
6076	+	double result;
6077	+	MapReduceEntriesToDoubleTask<K,V> sibling;
6078	+	MapReduceEntriesToDoubleTask
6079	+	(ConcurrentHashMap<K,V> m,
6080	+	ObjectToDouble<Map.Entry<K,V>> transformer,
6081	+	double basis,
6082	+	DoubleByDoubleToDouble reducer) {
6083	+	super(m);
6084	+	this.transformer = transformer;
6085	+	this.basis = basis; this.reducer = reducer;
6086	+	}
6087	+	MapReduceEntriesToDoubleTask
6088	+	(BulkTask<K,V,?> p, int b, boolean split,
6089	+	ObjectToDouble<Map.Entry<K,V>> transformer,
6090	+	double basis,
6091	+	DoubleByDoubleToDouble reducer) {
6092	+	super(p, b, split);
6093	+	this.transformer = transformer;
6094	+	this.basis = basis; this.reducer = reducer;
6095	+	}
6096	+	@SuppressWarnings("unchecked") public final void compute() {
6097	+	MapReduceEntriesToDoubleTask<K,V> t = this;
6098	+	final ObjectToDouble<Map.Entry<K,V>> transformer =
6099	+	this.transformer;
6100	+	final DoubleByDoubleToDouble reducer = this.reducer;
6101	+	if (transformer == null || reducer == null)
6102	+	throw new Error(NullFunctionMessage);
6103	+	final double id = this.basis;
6104	+	int b = batch();
6105	+	while (b > 1 && t.baseIndex != t.baseLimit) {
6106	+	b >>>= 1;
6107	+	t.pending = 1;
6108	+	MapReduceEntriesToDoubleTask<K,V> rt =
6109	+	new MapReduceEntriesToDoubleTask<K,V>
6110	+	(t, b, true, transformer, id, reducer);
6111	+	t = new MapReduceEntriesToDoubleTask<K,V>
6112	+	(t, b, false, transformer, id, reducer);
6113	+	t.sibling = rt;
6114	+	rt.sibling = t;
6115	+	rt.fork();
6116	+	}
6117	+	double r = id;
6118	+	Object v;
6119	+	while ((v = t.advance()) != null)
6120	+	r = reducer.apply(r, transformer.apply(entryFor((K)t.nextKey, (V)v)));
6121	+	t.result = r;
6122	+	for (;;) {
6123	+	int c; BulkTask<K,V,?> par; MapReduceEntriesToDoubleTask<K,V> s, p;
6124	+	if ((par = t.parent) == null ||
6125	+	!(par instanceof MapReduceEntriesToDoubleTask)) {
6126	+	t.quietlyComplete();
6127	+	break;
6128	+	}
6129	+	else if ((c = (p = (MapReduceEntriesToDoubleTask<K,V>)par).pending) == 0) {
6130	+	if ((s = t.sibling) != null)
6131	+	r = reducer.apply(r, s.result);
6132	+	(t = p).result = r;
6133	+	}
6134	+	else if (p.casPending(c, 0))
6135	+	break;
6136	+	}
6137	+	}
6138	+	public final Double getRawResult() { return result; }
6139	+	}
6140	+
6141	+	@SuppressWarnings("serial")
6142	+	static final class MapReduceMappingsToDoubleTask<K,V>
6143	+	extends BulkTask<K,V,Double> {
6144	+	final ObjectByObjectToDouble<? super K, ? super V> transformer;
6145	+	final DoubleByDoubleToDouble reducer;
6146	+	final double basis;
6147	+	double result;
6148	+	MapReduceMappingsToDoubleTask<K,V> sibling;
6149	+	MapReduceMappingsToDoubleTask
6150	+	(ConcurrentHashMap<K,V> m,
6151	+	ObjectByObjectToDouble<? super K, ? super V> transformer,
6152	+	double basis,
6153	+	DoubleByDoubleToDouble reducer) {
6154	+	super(m);
6155	+	this.transformer = transformer;
6156	+	this.basis = basis; this.reducer = reducer;
6157	+	}
6158	+	MapReduceMappingsToDoubleTask
6159	+	(BulkTask<K,V,?> p, int b, boolean split,
6160	+	ObjectByObjectToDouble<? super K, ? super V> transformer,
6161	+	double basis,
6162	+	DoubleByDoubleToDouble reducer) {
6163	+	super(p, b, split);
6164	+	this.transformer = transformer;
6165	+	this.basis = basis; this.reducer = reducer;
6166	+	}
6167	+	@SuppressWarnings("unchecked") public final void compute() {
6168	+	MapReduceMappingsToDoubleTask<K,V> t = this;
6169	+	final ObjectByObjectToDouble<? super K, ? super V> transformer =
6170	+	this.transformer;
6171	+	final DoubleByDoubleToDouble reducer = this.reducer;
6172	+	if (transformer == null || reducer == null)
6173	+	throw new Error(NullFunctionMessage);
6174	+	final double id = this.basis;
6175	+	int b = batch();
6176	+	while (b > 1 && t.baseIndex != t.baseLimit) {
6177	+	b >>>= 1;
6178	+	t.pending = 1;
6179	+	MapReduceMappingsToDoubleTask<K,V> rt =
6180	+	new MapReduceMappingsToDoubleTask<K,V>
6181	+	(t, b, true, transformer, id, reducer);
6182	+	t = new MapReduceMappingsToDoubleTask<K,V>
6183	+	(t, b, false, transformer, id, reducer);
6184	+	t.sibling = rt;
6185	+	rt.sibling = t;
6186	+	rt.fork();
6187	+	}
6188	+	double r = id;
6189	+	Object v;
6190	+	while ((v = t.advance()) != null)
6191	+	r = reducer.apply(r, transformer.apply((K)t.nextKey, (V)v));
6192	+	t.result = r;
6193	+	for (;;) {
6194	+	int c; BulkTask<K,V,?> par; MapReduceMappingsToDoubleTask<K,V> s, p;
6195	+	if ((par = t.parent) == null ||
6196	+	!(par instanceof MapReduceMappingsToDoubleTask)) {
6197	+	t.quietlyComplete();
6198	+	break;
6199	+	}
6200	+	else if ((c = (p = (MapReduceMappingsToDoubleTask<K,V>)par).pending) == 0) {
6201	+	if ((s = t.sibling) != null)
6202	+	r = reducer.apply(r, s.result);
6203	+	(t = p).result = r;
6204	+	}
6205	+	else if (p.casPending(c, 0))
6206	+	break;
6207	+	}
6208	+	}
6209	+	public final Double getRawResult() { return result; }
6210	+	}
6211	+
6212	+	@SuppressWarnings("serial")
6213	+	static final class MapReduceKeysToLongTask<K,V>
6214	+	extends BulkTask<K,V,Long> {
6215	+	final ObjectToLong<? super K> transformer;
6216	+	final LongByLongToLong reducer;
6217	+	final long basis;
6218	+	long result;
6219	+	MapReduceKeysToLongTask<K,V> sibling;
6220	+	MapReduceKeysToLongTask
6221	+	(ConcurrentHashMap<K,V> m,
6222	+	ObjectToLong<? super K> transformer,
6223	+	long basis,
6224	+	LongByLongToLong reducer) {
6225	+	super(m);
6226	+	this.transformer = transformer;
6227	+	this.basis = basis; this.reducer = reducer;
6228	+	}
6229	+	MapReduceKeysToLongTask
6230	+	(BulkTask<K,V,?> p, int b, boolean split,
6231	+	ObjectToLong<? super K> transformer,
6232	+	long basis,
6233	+	LongByLongToLong reducer) {
6234	+	super(p, b, split);
6235	+	this.transformer = transformer;
6236	+	this.basis = basis; this.reducer = reducer;
6237	+	}
6238	+	@SuppressWarnings("unchecked") public final void compute() {
6239	+	MapReduceKeysToLongTask<K,V> t = this;
6240	+	final ObjectToLong<? super K> transformer =
6241	+	this.transformer;
6242	+	final LongByLongToLong reducer = this.reducer;
6243	+	if (transformer == null || reducer == null)
6244	+	throw new Error(NullFunctionMessage);
6245	+	final long id = this.basis;
6246	+	int b = batch();
6247	+	while (b > 1 && t.baseIndex != t.baseLimit) {
6248	+	b >>>= 1;
6249	+	t.pending = 1;
6250	+	MapReduceKeysToLongTask<K,V> rt =
6251	+	new MapReduceKeysToLongTask<K,V>
6252	+	(t, b, true, transformer, id, reducer);
6253	+	t = new MapReduceKeysToLongTask<K,V>
6254	+	(t, b, false, transformer, id, reducer);
6255	+	t.sibling = rt;
6256	+	rt.sibling = t;
6257	+	rt.fork();
6258	+	}
6259	+	long r = id;
6260	+	while (t.advance() != null)
6261	+	r = reducer.apply(r, transformer.apply((K)t.nextKey));
6262	+	t.result = r;
6263	+	for (;;) {
6264	+	int c; BulkTask<K,V,?> par; MapReduceKeysToLongTask<K,V> s, p;
6265	+	if ((par = t.parent) == null ||
6266	+	!(par instanceof MapReduceKeysToLongTask)) {
6267	+	t.quietlyComplete();
6268	+	break;
6269	+	}
6270	+	else if ((c = (p = (MapReduceKeysToLongTask<K,V>)par).pending) == 0) {
6271	+	if ((s = t.sibling) != null)
6272	+	r = reducer.apply(r, s.result);
6273	+	(t = p).result = r;
6274	+	}
6275	+	else if (p.casPending(c, 0))
6276	+	break;
6277	+	}
6278	+	}
6279	+	public final Long getRawResult() { return result; }
6280	+	}
6281	+
6282	+	@SuppressWarnings("serial")
6283	+	static final class MapReduceValuesToLongTask<K,V>
6284	+	extends BulkTask<K,V,Long> {
6285	+	final ObjectToLong<? super V> transformer;
6286	+	final LongByLongToLong reducer;
6287	+	final long basis;
6288	+	long result;
6289	+	MapReduceValuesToLongTask<K,V> sibling;
6290	+	MapReduceValuesToLongTask
6291	+	(ConcurrentHashMap<K,V> m,
6292	+	ObjectToLong<? super V> transformer,
6293	+	long basis,
6294	+	LongByLongToLong reducer) {
6295	+	super(m);
6296	+	this.transformer = transformer;
6297	+	this.basis = basis; this.reducer = reducer;
6298	+	}
6299	+	MapReduceValuesToLongTask
6300	+	(BulkTask<K,V,?> p, int b, boolean split,
6301	+	ObjectToLong<? super V> transformer,
6302	+	long basis,
6303	+	LongByLongToLong reducer) {
6304	+	super(p, b, split);
6305	+	this.transformer = transformer;
6306	+	this.basis = basis; this.reducer = reducer;
6307	+	}
6308	+	@SuppressWarnings("unchecked") public final void compute() {
6309	+	MapReduceValuesToLongTask<K,V> t = this;
6310	+	final ObjectToLong<? super V> transformer =
6311	+	this.transformer;
6312	+	final LongByLongToLong reducer = this.reducer;
6313	+	if (transformer == null || reducer == null)
6314	+	throw new Error(NullFunctionMessage);
6315	+	final long id = this.basis;
6316	+	int b = batch();
6317	+	while (b > 1 && t.baseIndex != t.baseLimit) {
6318	+	b >>>= 1;
6319	+	t.pending = 1;
6320	+	MapReduceValuesToLongTask<K,V> rt =
6321	+	new MapReduceValuesToLongTask<K,V>
6322	+	(t, b, true, transformer, id, reducer);
6323	+	t = new MapReduceValuesToLongTask<K,V>
6324	+	(t, b, false, transformer, id, reducer);
6325	+	t.sibling = rt;
6326	+	rt.sibling = t;
6327	+	rt.fork();
6328	+	}
6329	+	long r = id;
6330	+	Object v;
6331	+	while ((v = t.advance()) != null)
6332	+	r = reducer.apply(r, transformer.apply((V)v));
6333	+	t.result = r;
6334	+	for (;;) {
6335	+	int c; BulkTask<K,V,?> par; MapReduceValuesToLongTask<K,V> s, p;
6336	+	if ((par = t.parent) == null ||
6337	+	!(par instanceof MapReduceValuesToLongTask)) {
6338	+	t.quietlyComplete();
6339	+	break;
6340	+	}
6341	+	else if ((c = (p = (MapReduceValuesToLongTask<K,V>)par).pending) == 0) {
6342	+	if ((s = t.sibling) != null)
6343	+	r = reducer.apply(r, s.result);
6344	+	(t = p).result = r;
6345	+	}
6346	+	else if (p.casPending(c, 0))
6347	+	break;
6348	+	}
6349	+	}
6350	+	public final Long getRawResult() { return result; }
6351	+	}
6352	+
6353	+	@SuppressWarnings("serial")
6354	+	static final class MapReduceEntriesToLongTask<K,V>
6355	+	extends BulkTask<K,V,Long> {
6356	+	final ObjectToLong<Map.Entry<K,V>> transformer;
6357	+	final LongByLongToLong reducer;
6358	+	final long basis;
6359	+	long result;
6360	+	MapReduceEntriesToLongTask<K,V> sibling;
6361	+	MapReduceEntriesToLongTask
6362	+	(ConcurrentHashMap<K,V> m,
6363	+	ObjectToLong<Map.Entry<K,V>> transformer,
6364	+	long basis,
6365	+	LongByLongToLong reducer) {
6366	+	super(m);
6367	+	this.transformer = transformer;
6368	+	this.basis = basis; this.reducer = reducer;
6369	+	}
6370	+	MapReduceEntriesToLongTask
6371	+	(BulkTask<K,V,?> p, int b, boolean split,
6372	+	ObjectToLong<Map.Entry<K,V>> transformer,
6373	+	long basis,
6374	+	LongByLongToLong reducer) {
6375	+	super(p, b, split);
6376	+	this.transformer = transformer;
6377	+	this.basis = basis; this.reducer = reducer;
6378	+	}
6379	+	@SuppressWarnings("unchecked") public final void compute() {
6380	+	MapReduceEntriesToLongTask<K,V> t = this;
6381	+	final ObjectToLong<Map.Entry<K,V>> transformer =
6382	+	this.transformer;
6383	+	final LongByLongToLong reducer = this.reducer;
6384	+	if (transformer == null || reducer == null)
6385	+	throw new Error(NullFunctionMessage);
6386	+	final long id = this.basis;
6387	+	int b = batch();
6388	+	while (b > 1 && t.baseIndex != t.baseLimit) {
6389	+	b >>>= 1;
6390	+	t.pending = 1;
6391	+	MapReduceEntriesToLongTask<K,V> rt =
6392	+	new MapReduceEntriesToLongTask<K,V>
6393	+	(t, b, true, transformer, id, reducer);
6394	+	t = new MapReduceEntriesToLongTask<K,V>
6395	+	(t, b, false, transformer, id, reducer);
6396	+	t.sibling = rt;
6397	+	rt.sibling = t;
6398	+	rt.fork();
6399	+	}
6400	+	long r = id;
6401	+	Object v;
6402	+	while ((v = t.advance()) != null)
6403	+	r = reducer.apply(r, transformer.apply(entryFor((K)t.nextKey, (V)v)));
6404	+	t.result = r;
6405	+	for (;;) {
6406	+	int c; BulkTask<K,V,?> par; MapReduceEntriesToLongTask<K,V> s, p;
6407	+	if ((par = t.parent) == null ||
6408	+	!(par instanceof MapReduceEntriesToLongTask)) {
6409	+	t.quietlyComplete();
6410	+	break;
6411	+	}
6412	+	else if ((c = (p = (MapReduceEntriesToLongTask<K,V>)par).pending) == 0) {
6413	+	if ((s = t.sibling) != null)
6414	+	r = reducer.apply(r, s.result);
6415	+	(t = p).result = r;
6416	+	}
6417	+	else if (p.casPending(c, 0))
6418	+	break;
6419	+	}
6420	+	}
6421	+	public final Long getRawResult() { return result; }
6422	+	}
6423	+
6424	+	@SuppressWarnings("serial")
6425	+	static final class MapReduceMappingsToLongTask<K,V>
6426	+	extends BulkTask<K,V,Long> {
6427	+	final ObjectByObjectToLong<? super K, ? super V> transformer;
6428	+	final LongByLongToLong reducer;
6429	+	final long basis;
6430	+	long result;
6431	+	MapReduceMappingsToLongTask<K,V> sibling;
6432	+	MapReduceMappingsToLongTask
6433	+	(ConcurrentHashMap<K,V> m,
6434	+	ObjectByObjectToLong<? super K, ? super V> transformer,
6435	+	long basis,
6436	+	LongByLongToLong reducer) {
6437	+	super(m);
6438	+	this.transformer = transformer;
6439	+	this.basis = basis; this.reducer = reducer;
6440	+	}
6441	+	MapReduceMappingsToLongTask
6442	+	(BulkTask<K,V,?> p, int b, boolean split,
6443	+	ObjectByObjectToLong<? super K, ? super V> transformer,
6444	+	long basis,
6445	+	LongByLongToLong reducer) {
6446	+	super(p, b, split);
6447	+	this.transformer = transformer;
6448	+	this.basis = basis; this.reducer = reducer;
6449	+	}
6450	+	@SuppressWarnings("unchecked") public final void compute() {
6451	+	MapReduceMappingsToLongTask<K,V> t = this;
6452	+	final ObjectByObjectToLong<? super K, ? super V> transformer =
6453	+	this.transformer;
6454	+	final LongByLongToLong reducer = this.reducer;
6455	+	if (transformer == null || reducer == null)
6456	+	throw new Error(NullFunctionMessage);
6457	+	final long id = this.basis;
6458	+	int b = batch();
6459	+	while (b > 1 && t.baseIndex != t.baseLimit) {
6460	+	b >>>= 1;
6461	+	t.pending = 1;
6462	+	MapReduceMappingsToLongTask<K,V> rt =
6463	+	new MapReduceMappingsToLongTask<K,V>
6464	+	(t, b, true, transformer, id, reducer);
6465	+	t = new MapReduceMappingsToLongTask<K,V>
6466	+	(t, b, false, transformer, id, reducer);
6467	+	t.sibling = rt;
6468	+	rt.sibling = t;
6469	+	rt.fork();
6470	+	}
6471	+	long r = id;
6472	+	Object v;
6473	+	while ((v = t.advance()) != null)
6474	+	r = reducer.apply(r, transformer.apply((K)t.nextKey, (V)v));
6475	+	t.result = r;
6476	+	for (;;) {
6477	+	int c; BulkTask<K,V,?> par; MapReduceMappingsToLongTask<K,V> s, p;
6478	+	if ((par = t.parent) == null ||
6479	+	!(par instanceof MapReduceMappingsToLongTask)) {
6480	+	t.quietlyComplete();
6481	+	break;
6482	+	}
6483	+	else if ((c = (p = (MapReduceMappingsToLongTask<K,V>)par).pending) == 0) {
6484	+	if ((s = t.sibling) != null)
6485	+	r = reducer.apply(r, s.result);
6486	+	(t = p).result = r;
6487	+	}
6488	+	else if (p.casPending(c, 0))
6489	+	break;
6490	+	}
6491	+	}
6492	+	public final Long getRawResult() { return result; }
6493	+	}
6494	+
6495	+	@SuppressWarnings("serial")
6496	+	static final class MapReduceKeysToIntTask<K,V>
6497	+	extends BulkTask<K,V,Integer> {
6498	+	final ObjectToInt<? super K> transformer;
6499	+	final IntByIntToInt reducer;
6500	+	final int basis;
6501	+	int result;
6502	+	MapReduceKeysToIntTask<K,V> sibling;
6503	+	MapReduceKeysToIntTask
6504	+	(ConcurrentHashMap<K,V> m,
6505	+	ObjectToInt<? super K> transformer,
6506	+	int basis,
6507	+	IntByIntToInt reducer) {
6508	+	super(m);
6509	+	this.transformer = transformer;
6510	+	this.basis = basis; this.reducer = reducer;
6511	+	}
6512	+	MapReduceKeysToIntTask
6513	+	(BulkTask<K,V,?> p, int b, boolean split,
6514	+	ObjectToInt<? super K> transformer,
6515	+	int basis,
6516	+	IntByIntToInt reducer) {
6517	+	super(p, b, split);
6518	+	this.transformer = transformer;
6519	+	this.basis = basis; this.reducer = reducer;
6520	+	}
6521	+	@SuppressWarnings("unchecked") public final void compute() {
6522	+	MapReduceKeysToIntTask<K,V> t = this;
6523	+	final ObjectToInt<? super K> transformer =
6524	+	this.transformer;
6525	+	final IntByIntToInt reducer = this.reducer;
6526	+	if (transformer == null || reducer == null)
6527	+	throw new Error(NullFunctionMessage);
6528	+	final int id = this.basis;
6529	+	int b = batch();
6530	+	while (b > 1 && t.baseIndex != t.baseLimit) {
6531	+	b >>>= 1;
6532	+	t.pending = 1;
6533	+	MapReduceKeysToIntTask<K,V> rt =
6534	+	new MapReduceKeysToIntTask<K,V>
6535	+	(t, b, true, transformer, id, reducer);
6536	+	t = new MapReduceKeysToIntTask<K,V>
6537	+	(t, b, false, transformer, id, reducer);
6538	+	t.sibling = rt;
6539	+	rt.sibling = t;
6540	+	rt.fork();
6541	+	}
6542	+	int r = id;
6543	+	while (t.advance() != null)
6544	+	r = reducer.apply(r, transformer.apply((K)t.nextKey));
6545	+	t.result = r;
6546	+	for (;;) {
6547	+	int c; BulkTask<K,V,?> par; MapReduceKeysToIntTask<K,V> s, p;
6548	+	if ((par = t.parent) == null ||
6549	+	!(par instanceof MapReduceKeysToIntTask)) {
6550	+	t.quietlyComplete();
6551	+	break;
6552	+	}
6553	+	else if ((c = (p = (MapReduceKeysToIntTask<K,V>)par).pending) == 0) {
6554	+	if ((s = t.sibling) != null)
6555	+	r = reducer.apply(r, s.result);
6556	+	(t = p).result = r;
6557	+	}
6558	+	else if (p.casPending(c, 0))
6559	+	break;
6560	+	}
6561	+	}
6562	+	public final Integer getRawResult() { return result; }
6563	+	}
6564	+
6565	+	@SuppressWarnings("serial")
6566	+	static final class MapReduceValuesToIntTask<K,V>
6567	+	extends BulkTask<K,V,Integer> {
6568	+	final ObjectToInt<? super V> transformer;
6569	+	final IntByIntToInt reducer;
6570	+	final int basis;
6571	+	int result;
6572	+	MapReduceValuesToIntTask<K,V> sibling;
6573	+	MapReduceValuesToIntTask
6574	+	(ConcurrentHashMap<K,V> m,
6575	+	ObjectToInt<? super V> transformer,
6576	+	int basis,
6577	+	IntByIntToInt reducer) {
6578	+	super(m);
6579	+	this.transformer = transformer;
6580	+	this.basis = basis; this.reducer = reducer;
6581	+	}
6582	+	MapReduceValuesToIntTask
6583	+	(BulkTask<K,V,?> p, int b, boolean split,
6584	+	ObjectToInt<? super V> transformer,
6585	+	int basis,
6586	+	IntByIntToInt reducer) {
6587	+	super(p, b, split);
6588	+	this.transformer = transformer;
6589	+	this.basis = basis; this.reducer = reducer;
6590	+	}
6591	+	@SuppressWarnings("unchecked") public final void compute() {
6592	+	MapReduceValuesToIntTask<K,V> t = this;
6593	+	final ObjectToInt<? super V> transformer =
6594	+	this.transformer;
6595	+	final IntByIntToInt reducer = this.reducer;
6596	+	if (transformer == null || reducer == null)
6597	+	throw new Error(NullFunctionMessage);
6598	+	final int id = this.basis;
6599	+	int b = batch();
6600	+	while (b > 1 && t.baseIndex != t.baseLimit) {
6601	+	b >>>= 1;
6602	+	t.pending = 1;
6603	+	MapReduceValuesToIntTask<K,V> rt =
6604	+	new MapReduceValuesToIntTask<K,V>
6605	+	(t, b, true, transformer, id, reducer);
6606	+	t = new MapReduceValuesToIntTask<K,V>
6607	+	(t, b, false, transformer, id, reducer);
6608	+	t.sibling = rt;
6609	+	rt.sibling = t;
6610	+	rt.fork();
6611	+	}
6612	+	int r = id;
6613	+	Object v;
6614	+	while ((v = t.advance()) != null)
6615	+	r = reducer.apply(r, transformer.apply((V)v));
6616	+	t.result = r;
6617	+	for (;;) {
6618	+	int c; BulkTask<K,V,?> par; MapReduceValuesToIntTask<K,V> s, p;
6619	+	if ((par = t.parent) == null ||
6620	+	!(par instanceof MapReduceValuesToIntTask)) {
6621	+	t.quietlyComplete();
6622	+	break;
6623	+	}
6624	+	else if ((c = (p = (MapReduceValuesToIntTask<K,V>)par).pending) == 0) {
6625	+	if ((s = t.sibling) != null)
6626	+	r = reducer.apply(r, s.result);
6627	+	(t = p).result = r;
6628	+	}
6629	+	else if (p.casPending(c, 0))
6630	+	break;
6631	+	}
6632	+	}
6633	+	public final Integer getRawResult() { return result; }
6634	+	}
6635	+
6636	+	@SuppressWarnings("serial")
6637	+	static final class MapReduceEntriesToIntTask<K,V>
6638	+	extends BulkTask<K,V,Integer> {
6639	+	final ObjectToInt<Map.Entry<K,V>> transformer;
6640	+	final IntByIntToInt reducer;
6641	+	final int basis;
6642	+	int result;
6643	+	MapReduceEntriesToIntTask<K,V> sibling;
6644	+	MapReduceEntriesToIntTask
6645	+	(ConcurrentHashMap<K,V> m,
6646	+	ObjectToInt<Map.Entry<K,V>> transformer,
6647	+	int basis,
6648	+	IntByIntToInt reducer) {
6649	+	super(m);
6650	+	this.transformer = transformer;
6651	+	this.basis = basis; this.reducer = reducer;
6652	+	}
6653	+	MapReduceEntriesToIntTask
6654	+	(BulkTask<K,V,?> p, int b, boolean split,
6655	+	ObjectToInt<Map.Entry<K,V>> transformer,
6656	+	int basis,
6657	+	IntByIntToInt reducer) {
6658	+	super(p, b, split);
6659	+	this.transformer = transformer;
6660	+	this.basis = basis; this.reducer = reducer;
6661	+	}
6662	+	@SuppressWarnings("unchecked") public final void compute() {
6663	+	MapReduceEntriesToIntTask<K,V> t = this;
6664	+	final ObjectToInt<Map.Entry<K,V>> transformer =
6665	+	this.transformer;
6666	+	final IntByIntToInt reducer = this.reducer;
6667	+	if (transformer == null || reducer == null)
6668	+	throw new Error(NullFunctionMessage);
6669	+	final int id = this.basis;
6670	+	int b = batch();
6671	+	while (b > 1 && t.baseIndex != t.baseLimit) {
6672	+	b >>>= 1;
6673	+	t.pending = 1;
6674	+	MapReduceEntriesToIntTask<K,V> rt =
6675	+	new MapReduceEntriesToIntTask<K,V>
6676	+	(t, b, true, transformer, id, reducer);
6677	+	t = new MapReduceEntriesToIntTask<K,V>
6678	+	(t, b, false, transformer, id, reducer);
6679	+	t.sibling = rt;
6680	+	rt.sibling = t;
6681	+	rt.fork();
6682	+	}
6683	+	int r = id;
6684	+	Object v;
6685	+	while ((v = t.advance()) != null)
6686	+	r = reducer.apply(r, transformer.apply(entryFor((K)t.nextKey, (V)v)));
6687	+	t.result = r;
6688	+	for (;;) {
6689	+	int c; BulkTask<K,V,?> par; MapReduceEntriesToIntTask<K,V> s, p;
6690	+	if ((par = t.parent) == null ||
6691	+	!(par instanceof MapReduceEntriesToIntTask)) {
6692	+	t.quietlyComplete();
6693	+	break;
6694	+	}
6695	+	else if ((c = (p = (MapReduceEntriesToIntTask<K,V>)par).pending) == 0) {
6696	+	if ((s = t.sibling) != null)
6697	+	r = reducer.apply(r, s.result);
6698	+	(t = p).result = r;
6699	+	}
6700	+	else if (p.casPending(c, 0))
6701	+	break;
6702	+	}
6703	+	}
6704	+	public final Integer getRawResult() { return result; }
6705	+	}
6706	+
6707	+	@SuppressWarnings("serial")
6708	+	static final class MapReduceMappingsToIntTask<K,V>
6709	+	extends BulkTask<K,V,Integer> {
6710	+	final ObjectByObjectToInt<? super K, ? super V> transformer;
6711	+	final IntByIntToInt reducer;
6712	+	final int basis;
6713	+	int result;
6714	+	MapReduceMappingsToIntTask<K,V> sibling;
6715	+	MapReduceMappingsToIntTask
6716	+	(ConcurrentHashMap<K,V> m,
6717	+	ObjectByObjectToInt<? super K, ? super V> transformer,
6718	+	int basis,
6719	+	IntByIntToInt reducer) {
6720	+	super(m);
6721	+	this.transformer = transformer;
6722	+	this.basis = basis; this.reducer = reducer;
6723	+	}
6724	+	MapReduceMappingsToIntTask
6725	+	(BulkTask<K,V,?> p, int b, boolean split,
6726	+	ObjectByObjectToInt<? super K, ? super V> transformer,
6727	+	int basis,
6728	+	IntByIntToInt reducer) {
6729	+	super(p, b, split);
6730	+	this.transformer = transformer;
6731	+	this.basis = basis; this.reducer = reducer;
6732	+	}
6733	+	@SuppressWarnings("unchecked") public final void compute() {
6734	+	MapReduceMappingsToIntTask<K,V> t = this;
6735	+	final ObjectByObjectToInt<? super K, ? super V> transformer =
6736	+	this.transformer;
6737	+	final IntByIntToInt reducer = this.reducer;
6738	+	if (transformer == null || reducer == null)
6739	+	throw new Error(NullFunctionMessage);
6740	+	final int id = this.basis;
6741	+	int b = batch();
6742	+	while (b > 1 && t.baseIndex != t.baseLimit) {
6743	+	b >>>= 1;
6744	+	t.pending = 1;
6745	+	MapReduceMappingsToIntTask<K,V> rt =
6746	+	new MapReduceMappingsToIntTask<K,V>
6747	+	(t, b, true, transformer, id, reducer);
6748	+	t = new MapReduceMappingsToIntTask<K,V>
6749	+	(t, b, false, transformer, id, reducer);
6750	+	t.sibling = rt;
6751	+	rt.sibling = t;
6752	+	rt.fork();
6753	+	}
6754	+	int r = id;
6755	+	Object v;
6756	+	while ((v = t.advance()) != null)
6757	+	r = reducer.apply(r, transformer.apply((K)t.nextKey, (V)v));
6758	+	t.result = r;
6759	+	for (;;) {
6760	+	int c; BulkTask<K,V,?> par; MapReduceMappingsToIntTask<K,V> s, p;
6761	+	if ((par = t.parent) == null ||
6762	+	!(par instanceof MapReduceMappingsToIntTask)) {
6763	+	t.quietlyComplete();
6764	+	break;
6765	+	}
6766	+	else if ((c = (p = (MapReduceMappingsToIntTask<K,V>)par).pending) == 0) {
6767	+	if ((s = t.sibling) != null)
6768	+	r = reducer.apply(r, s.result);
6769	+	(t = p).result = r;
6770	+	}
6771	+	else if (p.casPending(c, 0))
6772	+	break;
6773	+	}
6774	+	}
6775	+	public final Integer getRawResult() { return result; }
6776	+	}
6777	+
6778	+
6779		// Unsafe mechanics
6780		private static final sun.misc.Unsafe UNSAFE;
6781	<	private static final long SBASE;
6782	<	private static final int SSHIFT;
6783	<	private static final long TBASE;
6784	<	private static final int TSHIFT;
6781	>	private static final long counterOffset;
6782	>	private static final long sizeCtlOffset;
6783	>	private static final long ABASE;
6784	>	private static final int ASHIFT;
6785
6786		static {
6787	<	int ss, ts;
6787	>	int ss;
6788		try {
6789		UNSAFE = sun.misc.Unsafe.getUnsafe();
6790	<	Class<?> tc = HashEntry[].class;
6791	<	Class<?> sc = Segment[].class;
6792	<	TBASE = UNSAFE.arrayBaseOffset(tc);
6793	<	SBASE = UNSAFE.arrayBaseOffset(sc);
6794	<	ts = UNSAFE.arrayIndexScale(tc);
6790	>	Class<?> k = ConcurrentHashMap.class;
6791	>	counterOffset = UNSAFE.objectFieldOffset
6792	>	(k.getDeclaredField("counter"));
6793	>	sizeCtlOffset = UNSAFE.objectFieldOffset
6794	>	(k.getDeclaredField("sizeCtl"));
6795	>	Class<?> sc = Node[].class;
6796	>	ABASE = UNSAFE.arrayBaseOffset(sc);
6797		ss = UNSAFE.arrayIndexScale(sc);
6798		} catch (Exception e) {
6799		throw new Error(e);
6800		}
6801	<	if ((ss & (ss-1)) != 0 || (ts & (ts-1)) != 0)
6801	>	if ((ss & (ss-1)) != 0)
6802		throw new Error("data type scale not a power of two");
6803	<	SSHIFT = 31 - Integer.numberOfLeadingZeros(ss);
1481	<	TSHIFT = 31 - Integer.numberOfLeadingZeros(ts);
6803	>	ASHIFT = 31 - Integer.numberOfLeadingZeros(ss);
6804		}
6805	<
1484	<	}
6805	>	}

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