java.util.concurrent
Class Semaphore.Sync

java.lang.Object
  java.util.concurrent.locks.AbstractQueuedSynchronizer
      java.util.concurrent.Semaphore.Sync

All Implemented Interfaces:

Serializable

Direct Known Subclasses:

Semaphore.FairSync, Semaphore.NonfairSync

Enclosing class:

Semaphore

abstract static class Semaphore.Sync
extends AbstractQueuedSynchronizer

Synchronization implementation for semaphore. Uses AQS state to represent permits. Subclassed into fair and nonfair versions.

Nested Class Summary

Nested classes/interfaces inherited from class java.util.concurrent.locks.AbstractQueuedSynchronizer

AbstractQueuedSynchronizer.ConditionObject

Constructor Summary

Semaphore.Sync(int permits)

Method Summary

(package private) int	drainPermits()
(package private) int	getPermits()
(package private) int	nonfairTryAcquireShared(int acquires)
(package private) void	reducePermits(int reductions)
protected boolean	tryReleaseShared(int releases) Attempts to set the state to reflect a release in shared mode.

Methods inherited from class java.util.concurrent.locks.AbstractQueuedSynchronizer

acquire, acquireInterruptibly, acquireShared, acquireSharedInterruptibly, compareAndSetState, getExclusiveQueuedThreads, getFirstQueuedThread, getQueuedThreads, getQueueLength, getSharedQueuedThreads, getState, getWaitingThreads, getWaitQueueLength, hasContended, hasQueuedThreads, hasWaiters, isHeldExclusively, isQueued, owns, release, releaseShared, setState, toString, tryAcquire, tryAcquireNanos, tryAcquireShared, tryAcquireSharedNanos, tryRelease

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Constructor Detail

Semaphore.Sync

Semaphore.Sync(int permits)

Method Detail

getPermits

final int getPermits()

nonfairTryAcquireShared

final int nonfairTryAcquireShared(int acquires)

tryReleaseShared

protected final boolean tryReleaseShared(int releases)

Description copied from class: AbstractQueuedSynchronizer

Attempts to set the state to reflect a release in shared mode.

This method is always invoked by the thread performing release.

The default implementation throws UnsupportedOperationException

Overrides:

tryReleaseShared in class AbstractQueuedSynchronizer

Parameters:

releases - the release argument. This value is always the one passed to a release method, or the current state value upon entry to a condition wait. The value is otherwise uninterpreted and can represent anything you like.

Returns:

true if this object is now in a fully released state, so that any waiting threads may attempt to acquire; and false otherwise.

reducePermits

final void reducePermits(int reductions)

drainPermits

final int drainPermits()