AbstractQueuedLongSynchronizer.ConditionObject

public class AbstractQueuedLongSynchronizer.ConditionObject extends Object
implements Condition Serializable

Condition implementation for a AbstractQueuedLongSynchronizer serving as the basis of a Lock implementation.

Method documentation for this class describes mechanics, not behavioral specifications from the point of view of Lock and Condition users. Exported versions of this class will in general need to be accompanied by documentation describing condition semantics that rely on those of the associated AbstractQueuedLongSynchronizer.

This class is Serializable, but all fields are transient, so deserialized conditions have no waiters.

Public Constructor Summary

ConditionObject() Creates a new ConditionObject instance.

Public Method Summary

final void	await() Implements interruptible condition wait.
final boolean	await(long time, TimeUnit unit) Implements timed condition wait.
final long	awaitNanos(long nanosTimeout) Implements timed condition wait.
final void	awaitUninterruptibly() Implements uninterruptible condition wait.
final boolean	awaitUntil(Date deadline) Implements absolute timed condition wait.
final void	signal() Moves the longest-waiting thread, if one exists, from the wait queue for this condition to the wait queue for the owning lock.
final void	signalAll() Moves all threads from the wait queue for this condition to the wait queue for the owning lock.

Protected Method Summary

final int	getWaitQueueLength() Returns an estimate of the number of threads waiting on this condition.
final Collection<Thread>	getWaitingThreads() Returns a collection containing those threads that may be waiting on this Condition.
final boolean	hasWaiters() Queries whether any threads are waiting on this condition.

Inherited Method Summary

From class java.lang.Object

Object	clone() Creates and returns a copy of this Object.
boolean	equals(Object obj) Compares this instance with the specified object and indicates if they are equal.
void	finalize() Invoked when the garbage collector has detected that this instance is no longer reachable.
final Class<?>	getClass() Returns the unique instance of Class that represents this object's class.
int	hashCode() Returns an integer hash code for this object.
final void	notify() Causes a thread which is waiting on this object's monitor (by means of calling one of the wait() methods) to be woken up.
final void	notifyAll() Causes all threads which are waiting on this object's monitor (by means of calling one of the wait() methods) to be woken up.
String	toString() Returns a string containing a concise, human-readable description of this object.
final void	wait(long timeout, int nanos) Causes the calling thread to wait until another thread calls the notify() or notifyAll() method of this object or until the specified timeout expires.
final void	wait(long timeout) Causes the calling thread to wait until another thread calls the notify() or notifyAll() method of this object or until the specified timeout expires.
final void	wait() Causes the calling thread to wait until another thread calls the notify() or notifyAll() method of this object.

From interface java.util.concurrent.locks.Condition

abstract void	await() Causes the current thread to wait until it is signalled or {@linkplain Thread#interrupt interrupted}.
abstract boolean	await(long time, TimeUnit unit) Causes the current thread to wait until it is signalled or interrupted, or the specified waiting time elapses.
abstract long	awaitNanos(long nanosTimeout) Causes the current thread to wait until it is signalled or interrupted, or the specified waiting time elapses.
abstract void	awaitUninterruptibly() Causes the current thread to wait until it is signalled.
abstract boolean	awaitUntil(Date deadline) Causes the current thread to wait until it is signalled or interrupted, or the specified deadline elapses.
abstract void	signal() Wakes up one waiting thread.
abstract void	signalAll() Wakes up all waiting threads.

Public Constructors

public ConditionObject ()

Creates a new ConditionObject instance.

Public Methods

public final void await ()

Implements interruptible condition wait.

1. If current thread is interrupted, throw InterruptedException.
2. Save lock state returned by AbstractQueuedLongSynchronizer.getState().
3. Invoke AbstractQueuedLongSynchronizer.release(long) with saved state as argument, throwing IllegalMonitorStateException if it fails.
4. Block until signalled or interrupted.
5. Reacquire by invoking specialized version of AbstractQueuedLongSynchronizer.acquire(long) with saved state as argument.
6. If interrupted while blocked in step 4, throw InterruptedException.

Throws

InterruptedException

public final boolean await (long time, TimeUnit unit)

Implements timed condition wait.

1. If current thread is interrupted, throw InterruptedException.
2. Save lock state returned by AbstractQueuedLongSynchronizer.getState().
3. Invoke AbstractQueuedLongSynchronizer.release(long) with saved state as argument, throwing IllegalMonitorStateException if it fails.
4. Block until signalled, interrupted, or timed out.
5. Reacquire by invoking specialized version of AbstractQueuedLongSynchronizer.acquire(long) with saved state as argument.
6. If interrupted while blocked in step 4, throw InterruptedException.
7. If timed out while blocked in step 4, return false, else true.

Parameters

time	the maximum time to wait
unit	the time unit of the time argument

Returns

• false if the waiting time detectably elapsed before return from the method, else true

Throws

InterruptedException

public final long awaitNanos (long nanosTimeout)

Implements timed condition wait.

1. If current thread is interrupted, throw InterruptedException.
2. Save lock state returned by AbstractQueuedLongSynchronizer.getState().
3. Invoke AbstractQueuedLongSynchronizer.release(long) with saved state as argument, throwing IllegalMonitorStateException if it fails.
4. Block until signalled, interrupted, or timed out.
5. Reacquire by invoking specialized version of AbstractQueuedLongSynchronizer.acquire(long) with saved state as argument.
6. If interrupted while blocked in step 4, throw InterruptedException.

Parameters

nanosTimeout	the maximum time to wait, in nanoseconds

Returns

• an estimate of the nanosTimeout value minus the time spent waiting upon return from this method. A positive value may be used as the argument to a subsequent call to this method to finish waiting out the desired time. A value less than or equal to zero indicates that no time remains.

Throws

InterruptedException

public final void awaitUninterruptibly ()

Implements uninterruptible condition wait.

1. Save lock state returned by AbstractQueuedLongSynchronizer.getState().
2. Invoke AbstractQueuedLongSynchronizer.release(long) with saved state as argument, throwing IllegalMonitorStateException if it fails.
3. Block until signalled.
4. Reacquire by invoking specialized version of AbstractQueuedLongSynchronizer.acquire(long) with saved state as argument.

public final boolean awaitUntil (Date deadline)

Implements absolute timed condition wait.

1. If current thread is interrupted, throw InterruptedException.
2. Save lock state returned by AbstractQueuedLongSynchronizer.getState().
3. Invoke AbstractQueuedLongSynchronizer.release(long) with saved state as argument, throwing IllegalMonitorStateException if it fails.
4. Block until signalled, interrupted, or timed out.
5. Reacquire by invoking specialized version of AbstractQueuedLongSynchronizer.acquire(long) with saved state as argument.
6. If interrupted while blocked in step 4, throw InterruptedException.
7. If timed out while blocked in step 4, return false, else true.

Parameters

deadline	the absolute time to wait until

Returns

• false if the deadline has elapsed upon return, else true

Throws

InterruptedException

public final void signal ()

Moves the longest-waiting thread, if one exists, from the wait queue for this condition to the wait queue for the owning lock.

Throws

IllegalMonitorStateException	if AbstractQueuedLongSynchronizer.isHeldExclusively() returns false

public final void signalAll ()

Moves all threads from the wait queue for this condition to the wait queue for the owning lock.

Throws

IllegalMonitorStateException	if AbstractQueuedLongSynchronizer.isHeldExclusively() returns false

Protected Methods

protected final int getWaitQueueLength ()

Returns an estimate of the number of threads waiting on this condition. Implements AbstractQueuedLongSynchronizer.getWaitQueueLength(ConditionObject).

Returns

• the estimated number of waiting threads

Throws

IllegalMonitorStateException	if AbstractQueuedLongSynchronizer.isHeldExclusively() returns false

protected final Collection<Thread> getWaitingThreads ()

Returns a collection containing those threads that may be waiting on this Condition. Implements AbstractQueuedLongSynchronizer.getWaitingThreads(ConditionObject).

Returns

• the collection of threads

Throws

IllegalMonitorStateException	if AbstractQueuedLongSynchronizer.isHeldExclusively() returns false

protected final boolean hasWaiters ()

Queries whether any threads are waiting on this condition. Implements AbstractQueuedLongSynchronizer.hasWaiters(ConditionObject).

Returns

• true if there are any waiting threads

Throws

IllegalMonitorStateException	if AbstractQueuedLongSynchronizer.isHeldExclusively() returns false