com.atlassian.jira.util.concurrent

Class BlockingCounter

java.lang.Object

com.atlassian.jira.util.concurrent.BlockingCounter

public final class BlockingCounter
extends Object

A simple counter that can will cause threads calling the await() method to block while its value is > 0. The counter may only be incremented and decremented and must have a value >= 0.

Since:

v4.1

Constructor Summary

Constructors

Constructor and Description
BlockingCounter()
BlockingCounter(int count)

Method Summary

Methods

Modifier and Type	Method and Description
void	await() Block while counter is > 0, throwing InterruptedException if interrupted.
boolean	await(long timeout, TimeUnit unit)
void	awaitUninterruptibly() Block while counter is > 0, ignoring interrupts.
void	down()
int	getCount()
int	getWaitingThreadCount() Get the number of threads currently waiting
String	toString()
void	up()
boolean	wouldBlock() Returns true if calling await() at the same very moment would block.

Methods inherited from class java.lang.Object

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

Constructor Detail

BlockingCounter

public BlockingCounter()

BlockingCounter

public BlockingCounter(int count)

Method Detail

up

public void up()

down

public void down()

await

public boolean await(long timeout,
            TimeUnit unit)
              throws InterruptedException

Throws:

InterruptedException

await

public void await()
           throws InterruptedException

Block while counter is > 0, throwing InterruptedException if interrupted.

Note the behaviour has changed since v6.1 - before that InterruptedException was never thrown due to a bug.

Throws:

InterruptedException

See Also:

AbstractQueuedSynchronizer.acquireSharedInterruptibly(int)

awaitUninterruptibly

public void awaitUninterruptibly()

Block while counter is > 0, ignoring interrupts.

Since:

v6.1

See Also:

AbstractQueuedSynchronizer.doAcquireShared(int)

wouldBlock

public boolean wouldBlock()

Returns true if calling await() at the same very moment would block.

Returns:

true when count is > 0 so await() would block

Since:

v6.1

getCount

public int getCount()

getWaitingThreadCount

public int getWaitingThreadCount()

Get the number of threads currently waiting

Returns:

the waiting thread count

toString

public String toString()

Overrides:

toString in class Object