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root/jsr166/jsr166/src/jsr166e/ConcurrentHashMapV8.java

Comparing jsr166/src/jsr166e/ConcurrentHashMapV8.java (file contents):
Revision 1.77 by jsr166, Sun Nov 18 03:07:22 2012 UTC vs.
Revision 1.78 by jsr166, Sun Nov 18 18:03:10 2012 UTC

#	Line 40 | Line 40 | import java.io.Serializable;
40		* interoperable with {@code Hashtable} in programs that rely on its
41		* thread safety but not on its synchronization details.
42		*
43	<	* <p> Retrieval operations (including {@code get}) generally do not
43	>	* <p>Retrieval operations (including {@code get}) generally do not
44		* block, so may overlap with update operations (including {@code put}
45		* and {@code remove}). Retrievals reflect the results of the most
46		* recently <em>completed</em> update operations holding upon their
#	Line 61 | Line 61 | import java.io.Serializable;
61		* that may be adequate for monitoring or estimation purposes, but not
62		* for program control.
63		*
64	<	* <p> The table is dynamically expanded when there are too many
64	>	* <p>The table is dynamically expanded when there are too many
65		* collisions (i.e., keys that have distinct hash codes but fall into
66		* the same slot modulo the table size), with the expected average
67		* effect of maintaining roughly two bins per mapping (corresponding
#	Line 82 | Line 82 | import java.io.Serializable;
82		* {@code hashCode()} is a sure way to slow down performance of any
83		* hash table.
84		*
85	<	* <p> A {@link Set} projection of a ConcurrentHashMapV8 may be created
85	>	* <p>A {@link Set} projection of a ConcurrentHashMapV8 may be created
86		* (using {@link #newKeySet()} or {@link #newKeySet(int)}), or viewed
87		* (using {@link #keySet(Object)} when only keys are of interest, and the
88		* mapped values are (perhaps transiently) not used or all take the
89		* same mapping value.
90		*
91	<	* <p> A ConcurrentHashMapV8 can be used as scalable frequency map (a
91	>	* <p>A ConcurrentHashMapV8 can be used as scalable frequency map (a
92		* form of histogram or multiset) by using {@link LongAdder} values
93		* and initializing via {@link #computeIfAbsent}. For example, to add
94		* a count to a {@code ConcurrentHashMapV8<String,LongAdder> freqs}, you
#	Line 99 | Line 99 | import java.io.Serializable;
99		* <em>optional</em> methods of the {@link Map} and {@link Iterator}
100		* interfaces.
101		*
102	<	* <p> Like {@link Hashtable} but unlike {@link HashMap}, this class
102	>	* <p>Like {@link Hashtable} but unlike {@link HashMap}, this class
103		* does <em>not</em> allow {@code null} to be used as a key or value.
104		*
105		* <p>ConcurrentHashMapV8s support parallel operations using the {@link
#	Line 184 | Line 184 | import java.io.Serializable;
184		* arguments can be supplied using {@code new
185		* AbstractMap.SimpleEntry(k,v)}.
186		*
187	<	* <p> Bulk operations may complete abruptly, throwing an
187	>	* <p>Bulk operations may complete abruptly, throwing an
188		* exception encountered in the application of a supplied
189		* function. Bear in mind when handling such exceptions that other
190		* concurrently executing functions could also have thrown
#	Line 199 | Line 199 | import java.io.Serializable;
199		* Similarly, parallelization may not lead to much actual parallelism
200		* if all processors are busy performing unrelated tasks.
201		*
202	<	* <p> All arguments to all task methods must be non-null.
202	>	* <p>All arguments to all task methods must be non-null.
203		*
204		* <p><em>jsr166e note: During transition, this class
205		* uses nested functional interfaces with different names but the
#	Line 225 | Line 225 | public class ConcurrentHashMapV8<K, V>
225		* portion of the elements, and so may be amenable to parallel
226		* execution.
227		*
228	<	* <p> This interface exports a subset of expected JDK8
228	>	* <p>This interface exports a subset of expected JDK8
229		* functionality.
230		*
231		* <p>Sample usage: Here is one (of the several) ways to compute
#	Line 2713 | Line 2713 | public class ConcurrentHashMapV8<K, V>
2713		* Maps the specified key to the specified value in this table.
2714		* Neither the key nor the value can be null.
2715		*
2716	<	* <p> The value can be retrieved by calling the {@code get} method
2716	>	* <p>The value can be retrieved by calling the {@code get} method
2717		* with a key that is equal to the original key.
2718		*
2719		* @param key key with which the specified value is to be associated

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