FIM.Synchronisation
Class Mutex

java.lang.Object
  |
  +--FIM.Synchronisation.Mutex

public final class Mutex

extends Object

A standard mutual exclusion as defined in books on operating systems. Used if only one thread at any time may execaute a certain piece of code. At the beginning of the critical section call lock and at the end unlock.

Version:

1.0, 1.7.2000

Author:

Michael Sonntag

See Also:

Thread

Constructor Summary

Mutex()

Method Summary

boolean	lock() Try to acquire the mutex.
boolean	lock(int millis) Try to acquire the mutex for up to a maximum of the provided time in milliseconds.
void	unlock() Releases the mutex.

Methods inherited from class java.lang.Object

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

Constructor Detail

Mutex

public Mutex()

Method Detail

lock

public boolean lock(int millis)
             throws InterruptedException

Try to acquire the mutex for up to a maximum of the provided time in milliseconds.

Parameters:

millis - number of milliseconds to wait. Providing 0 will wait indefinitely

Returns:

true if the mutex was acquired, false if the time ran out without success

Throws:

InterruptedException - if the wait for the mutex was interrupt

See Also:

Thread

lock

public boolean lock()
             throws InterruptedException

Try to acquire the mutex. Will wait indefinitely till the mutex is acquired or it is interrupt.

Returns:

true if the mutex was acquired, false if the time ran out without success

Throws:

InterruptedException - if the wait for the mutex was interrupted

See Also:

Thread

unlock

public void unlock()

Releases the mutex. May only be called by the thread possessing the mutex (else a RuntimeException will be thrown). If threads are waiting, one of them is released and can acquire the mutex. Which of them is NOT defined!