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/* |
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* Written by Doug Lea with assistance from members of JCP JSR-166 |
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* Expert Group and released to the public domain, as explained at |
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* http://creativecommons.org/publicdomain/zero/1.0/ |
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*/ |
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|
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/** |
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* Interfaces and classes providing a framework for locking and waiting |
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* for conditions that is distinct from built-in synchronization and |
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* monitors. The framework permits much greater flexibility in the use of |
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* locks and conditions, at the expense of more awkward syntax. |
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* |
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* <p>The {@link java.util.concurrent.locks.Lock} interface supports |
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* locking disciplines that differ in semantics (reentrant, fair, etc), |
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* and that can be used in non-block-structured contexts including |
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* hand-over-hand and lock reordering algorithms. The main implementation |
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* is {@link java.util.concurrent.locks.ReentrantLock}. |
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* |
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* <p>The {@link java.util.concurrent.locks.ReadWriteLock} interface |
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* similarly defines locks that may be shared among readers but are |
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* exclusive to writers. Only a single implementation, {@link |
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* java.util.concurrent.locks.ReentrantReadWriteLock}, is provided, since |
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* it covers most standard usage contexts. But programmers may create |
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* their own implementations to cover nonstandard requirements. |
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* |
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* <p>The {@link java.util.concurrent.locks.Condition} interface |
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* describes condition variables that may be associated with Locks. |
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* These are similar in usage to the implicit monitors accessed using |
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* {@code Object.wait}, but offer extended capabilities. |
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* In particular, multiple {@code Condition} objects may be associated |
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* with a single {@code Lock}. To avoid compatibility issues, the |
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* names of {@code Condition} methods are different from the |
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* corresponding {@code Object} versions. |
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* |
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* <p>The {@link java.util.concurrent.locks.AbstractQueuedSynchronizer} |
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* class serves as a useful superclass for defining locks and other |
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* synchronizers that rely on queuing blocked threads. The {@link |
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* java.util.concurrent.locks.AbstractQueuedLongSynchronizer} class |
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* provides the same functionality but extends support to 64 bits of |
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* synchronization state. Both extend class {@link |
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* java.util.concurrent.locks.AbstractOwnableSynchronizer}, a simple |
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* class that helps record the thread currently holding exclusive |
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* synchronization. The {@link java.util.concurrent.locks.LockSupport} |
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* class provides lower-level blocking and unblocking support that is |
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* useful for those developers implementing their own customized lock |
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* classes. |
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* |
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* @since 1.5 |
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*/ |
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package java.util.concurrent.locks; |
