org.springframework.integration.util

Class UpperBound

java.lang.Object

org.springframework.integration.util.UpperBound

public final class UpperBound
extends java.lang.Object

Thin wrapper around a Semaphore that allows to create a potentially unlimited upper bound to by used in buffers of messages (e.g. a QueueChannel or a MessageStore).

Since:

2.0

Author:

Mark Fisher, Iwein Fuld, Artem Bilan

Field Summary

Fields

Modifier and Type	Field and Description
java.util.concurrent.Semaphore	semaphore

Constructor Summary

Constructors

Constructor and Description
UpperBound(int capacity) Create an UpperBound with the given capacity.

Method Summary

Modifier and Type	Method and Description
int	availablePermits()
void	release() Releases one lock on the underlying semaphore.
void	release(int permits) Releases several locks on the underlying semaphore.
java.lang.String	toString()
boolean	tryAcquire(long timeoutInMilliseconds) Acquires a permit from the underlying semaphore if this UpperBound is bounded and returns true if it succeeds within the given timeout.

Methods inherited from class java.lang.Object

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

Field Detail

semaphore

public final java.util.concurrent.Semaphore semaphore

Constructor Detail

UpperBound

public UpperBound(int capacity)

Create an UpperBound with the given capacity. If the given capacity is less than 1 an infinite UpperBound is created.

Parameters:

capacity - The capacity.

Method Detail

availablePermits

public int availablePermits()

tryAcquire

public boolean tryAcquire(long timeoutInMilliseconds)

Acquires a permit from the underlying semaphore if this UpperBound is bounded and returns true if it succeeds within the given timeout. If the timeout is less than 0, it will block indefinitely.

Parameters:

timeoutInMilliseconds - The time to wait until a permit is available.

Returns:

true if a permit is acquired.

release

public void release()

Releases one lock on the underlying semaphore. This is typically not done by the same Thread that acquired the lock, but by the thread that picked up the message.

release

public void release(int permits)

Releases several locks on the underlying semaphore. This is typically not done by the same Thread that acquired the lock, but by the thread that picked up the message.

Parameters:

permits - The number of permits to release.

toString

public java.lang.String toString()

Overrides:

toString in class java.lang.Object