net.grinder.synchronisation

Class BarrierImplementation

java.lang.Object

net.grinder.synchronisation.BarrierImplementation

All Implemented Interfaces:

Barrier, BarrierGroup.Listener

public final class BarrierImplementation
extends Object
implements Barrier, BarrierGroup.Listener

Barrier implementation.

Author:

Philip Aston

Constructor Summary

Constructors

Constructor and Description
BarrierImplementation(BarrierGroup group, BarrierIdentity.Factory identityFactory) Constructor.

Method Summary

Methods

Modifier and Type	Method and Description
void	await() Wait until all other barriers with the same name have invoked Barrier.await().
boolean	await(long timeout) Equivalent to await(timeout, TimeUnit.MILLISECONDS).
boolean	await(long timeout, TimeUnit unit) Version of Barrier.await() that allows a timeout to be specified.
void	awaken(Set<BarrierIdentity> waiters)
void	cancel() Cancel this Barrier and reduce the total number of instances for the barrier name.
String	getName() Return the name of the barrier.

Methods inherited from class java.lang.Object

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

Constructor Detail

BarrierImplementation

public BarrierImplementation(BarrierGroup group,
                     BarrierIdentity.Factory identityFactory)
                      throws CommunicationException

Constructor.

Parameters:

group - Barrier group.

identityFactory - Identity generator.

Throws:

CommunicationException - If the barrier group could not be created due to a network communication problem.

Method Detail

await

public void await()
           throws CancelledBarrierException,
                  CommunicationException

Wait until all other barriers with the same name have invoked Barrier.await().

If this barrier is not the last with the name to call await and has not been cancelled, this method blocks until one of the following happens:

• await is called for the last barrier.
• All non-waiting barriers with the same name are cancelled.
• This barrier is cancelled.
• Some other thread interrupts the current thread. In this case, the barrier instance will be cancelled.

If this barrier is the last with the name to call await, the method will not block. All await calls made by other threads for barriers with the same name will complete.

Specified by:

await in interface Barrier

Throws:

CancelledBarrierException - If this barrier has been cancelled.

CommunicationException

await

public boolean await(long timeout,
            TimeUnit unit)
              throws CancelledBarrierException,
                     CommunicationException

Version of Barrier.await() that allows a timeout to be specified.

If the specified timeout elapses while the thread is waiting, the method will return false, and the barrier instance will be cancelled.

Specified by:

await in interface Barrier

Parameters:

timeout - The time to wait for the barrier.

unit - The time unit of the timeout parameter.

Returns:

false if and only if the waiting time detectably elapsed before return from the method.

Throws:

CancelledBarrierException - If this barrier has been cancelled.

CommunicationException

await

public boolean await(long timeout)
              throws CancelledBarrierException,
                     CommunicationException

Equivalent to await(timeout, TimeUnit.MILLISECONDS).

Specified by:

await in interface Barrier

Parameters:

timeout - The time to wait for the barrier.

Returns:

false if and only if the waiting time detectably elapsed before return from the method.

Throws:

CancelledBarrierException - If this barrier has been cancelled.

CommunicationException

awaken

public void awaken(Set<BarrierIdentity> waiters)

Specified by:

awaken in interface BarrierGroup.Listener

cancel

public void cancel()
            throws CommunicationException

Cancel this Barrier and reduce the total number of instances for the barrier name. If another thread is waiting on this barrier instance, it will receive a CancelledBarrierException. Otherwise, if this was the only idle barrier, the others with the same name will be awoken.

Subsequent calls to Barrier.await() for this Barrier will result in an CancelledBarrierException.

Specified by:

cancel in interface Barrier

Throws:

CommunicationException

getName

public String getName()

Return the name of the barrier.

Specified by:

getName in interface Barrier

Returns:

The barrier name.