RSE
Release 3.0

org.eclipse.rse.services
Class Mutex

java.lang.Object
  extended by org.eclipse.rse.services.Mutex

public class Mutex
extends Object

A Mutual Exclusion Lock for Threads that need to access a resource in a serialized manner. An Eclipse ProgressMonitor is accepted in order to support cancellation when waiting for the Mutex. Usage Example: private Mutex fooMutex = new Mutex(); boolean doFooSerialized()(IProgressMonitor monitor) { if (fooMutex.waitForLock(monitor, 1000)) { try { return doFoo(); } finally { fooMutex.release(); } } return false; } The Mutex is not reentrant, so when a Thread has locked the Mutex it must not try locking it again.


Constructor Summary
Mutex()
          Creates an instance of Mutex.
 
Method Summary
 void interruptAll()
          Interrupt all threads waiting for the Lock, causing their waitForLock(IProgressMonitor, long) method to return false.
 boolean isLocked()
          Return this Mutex's lock status.
 void release()
          Release this mutex's lock.
 boolean waitForLock(IProgressMonitor monitor, long timeout)
          Try to acquire the lock maintained by this mutex.
 
Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
 

Constructor Detail

Mutex

public Mutex()
Creates an instance of Mutex.

Method Detail

waitForLock

public boolean waitForLock(IProgressMonitor monitor,
                           long timeout)
Try to acquire the lock maintained by this mutex. If the thread needs to wait before it can acquire the mutex, it will wait in a first-come-first-serve fashion. In case a progress monitor was given, it will be updated and checked for cancel every second.

Parameters:
monitor - Eclipse Progress Monitor. May be null.
timeout - Maximum wait time given in milliseconds.
Returns:
true if the lock was obtained successfully.

release

public void release()
Release this mutex's lock. May only be called by the same thread that originally acquired the Mutex.


isLocked

public boolean isLocked()
Return this Mutex's lock status.

Returns:
true if this mutex is currently acquired by a thread.

interruptAll

public void interruptAll()
Interrupt all threads waiting for the Lock, causing their waitForLock(IProgressMonitor, long) method to return false. This should be called if the resource that the Threads are contending for, becomes unavailable for some other reason.


RSE
Release 3.0

Copyright (c) IBM Corporation and others 2000, 2008. All Rights Reserved.