java.util.concurrent.locks
Class ReentrantReadWriteLock.FairSync

java.lang.Object
  java.util.concurrent.locks.AbstractQueuedSynchronizer
      java.util.concurrent.locks.ReentrantReadWriteLock.Sync
          java.util.concurrent.locks.ReentrantReadWriteLock.FairSync

All Implemented Interfaces:

Serializable

Enclosing class:

ReentrantReadWriteLock

static final class ReentrantReadWriteLock.FairSync
extends ReentrantReadWriteLock.Sync

Fair version of Sync

Nested Class Summary

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

AbstractQueuedSynchronizer.ConditionObject, AbstractQueuedSynchronizer.Node

Field Summary

Fields inherited from class java.util.concurrent.locks.ReentrantReadWriteLock.Sync

owner

Constructor Summary

ReentrantReadWriteLock.FairSync()

Method Summary

protected boolean	tryAcquire(int acquires) Attempts to acquire in exclusive mode.
protected int	tryAcquireShared(int acquires) Attempts to acquire in shared mode.
(package private) void	wlock() Perform write lock.

Methods inherited from class java.util.concurrent.locks.ReentrantReadWriteLock.Sync

getCount, getOwner, getReadLockCount, getWriteHoldCount, isHeldExclusively, isWriteLocked, newCondition, nonfairTryAcquire, nonfairTryAcquireShared, tryRelease, tryReleaseShared

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

acquire, acquireInterruptibly, acquireQueued, acquireShared, acquireSharedInterruptibly, compareAndSetState, fullyRelease, getExclusiveQueuedThreads, getFirstQueuedThread, getQueuedThreads, getQueueLength, getSharedQueuedThreads, getState, getWaitingThreads, getWaitQueueLength, hasContended, hasQueuedThreads, hasWaiters, isOnSyncQueue, isQueued, owns, release, releaseShared, setState, toString, transferAfterCancelledWait, transferForSignal, tryAcquireNanos, tryAcquireSharedNanos

Methods inherited from class java.lang.Object

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

Constructor Detail

ReentrantReadWriteLock.FairSync

ReentrantReadWriteLock.FairSync()

Method Detail

tryAcquire

protected final boolean tryAcquire(int acquires)

Description copied from class: AbstractQueuedSynchronizer

Attempts to acquire in exclusive mode. This method should query if the state of the object permits it to be acquired in the exclusive mode, and if so to acquire it.

This method is always invoked by the thread performing acquire. If this method reports failure, the acquire method may queue the thread, if it is not already queued, until it is signalled by a release from some other thread. This can be used to implement method Lock.tryLock().

The default implementation throws UnsupportedOperationException

Overrides:

tryAcquire in class AbstractQueuedSynchronizer

Parameters:

acquires - the acquire argument. This value is always the one passed to an acquire method, or is the value saved on entry to a condition wait. The value is otherwise uninterpreted and can represent anything you like.

Returns:

true if successful. Upon success, this object has been acquired.

tryAcquireShared

protected final int tryAcquireShared(int acquires)

Description copied from class: AbstractQueuedSynchronizer

Attempts to acquire in shared mode. This method should query if the state of the object permits it to be acquired in the shared mode, and if so to acquire it.

This method is always invoked by the thread performing acquire. If this method reports failure, the acquire method may queue the thread, if it is not already queued, until it is signalled by a release from some other thread.

The default implementation throws UnsupportedOperationException

Overrides:

tryAcquireShared in class AbstractQueuedSynchronizer

Parameters:

acquires - the acquire argument. This value is always the one passed to an acquire method, or is the value saved on entry to a condition wait. The value is otherwise uninterpreted and can represent anything you like.

Returns:

a negative value on failure, zero on exclusive success, and a positive value if non-exclusively successful, in which case a subsequent waiting thread must check availability. (Support for three different return values enables this method to be used in contexts where acquires only sometimes act exclusively.) Upon success, this object has been acquired.

wlock

final void wlock()

Description copied from class: ReentrantReadWriteLock.Sync

Perform write lock. Allows fast path in non-fair version.

Specified by:

wlock in class ReentrantReadWriteLock.Sync