org.opennms.core.concurrent
Class QuantumSemaphore

java.lang.Object
  org.opennms.core.concurrent.QuantumSemaphore

public final class QuantumSemaphore
extends Object

QuantumSemaphore class is similar to a semaphore, but slightly different. The class provides for a way to acquire a resource, but not to release one. The idea is that the value of the semaphore is reset each quantum to it's maximum value.

Author:

Sowmya

Constructor Summary

QuantumSemaphore(long maxValue, long quantum)
Constructs a new QuantumSempahore object with the specified maximum value and time quantum.

Method Summary

boolean	acquire() Returns a true value if the semaphore is successfully acquired by the application.
long	getMaxValue() Returns the maximum value of the QuantumSemaphore.

Methods inherited from class java.lang.Object

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

Constructor Detail

QuantumSemaphore

public QuantumSemaphore(long maxValue,
                        long quantum)

Constructs a new QuantumSempahore object with the specified maximum value and time quantum. The object's values cannot be change once the object is created.

Parameters:

maxValue - The maximum value of the semaphore

quantum - The time quantum between resets, in milliseconds.

Method Detail

acquire

public boolean acquire()
                throws InterruptedException

Returns a true value if the semaphore is successfully acquired by the application. A false value is returned if the acquisition does not work.

Returns:

True if the semaphore is acquired, false otherwise.

Throws:

InterruptedException - if any.

getMaxValue

public long getMaxValue()

Returns the maximum value of the QuantumSemaphore.

Returns:

a long.