org.safs.staf.service.sem

Class MutexState

java.lang.Object

org.safs.staf.service.sem.SEMState

org.safs.staf.service.sem.MutexState

public class MutexState
extends SEMState

Author:

Carl Nagle

Field Summary

Fields inherited from class org.safs.staf.service.sem.SEMState

MAX_STATE, MIN_STATE, sem, STATE_DESC, STATE_INVALID, STATE_POSTED, STATE_RELEASED, STATE_REQUESTED, STATE_RESET, STATE_WAITING

Constructor Summary

Constructors

Constructor and Description
MutexState(java.lang.String itemname, int itemstate)

Method Summary

Modifier and Type	Method and Description
boolean	isAvailable()
com.ibm.staf.STAFResult	releaseMutex(java.lang.String holder) Release 1 (and only 1) Mutex waiter currently registered for the item.
void	releaseWaiters() Used internally.
com.ibm.staf.STAFResult	requestMutex(java.lang.String holder) Request exclusive ownership of the Mutex. Calling thread will be blocked until access is granted.

Methods inherited from class org.safs.staf.service.sem.SEMState

addWaiter, addWaiter, addWaiterId, getItemName, getItemState, getStateDesc, getWaiterIds, hasWaiters, removeWaiterId, setItemState

Methods inherited from class java.lang.Object

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

Constructor Detail

MutexState

public MutexState(java.lang.String itemname,
                  int itemstate)

Parameters:

itemname -

itemstate -

Method Detail

releaseWaiters

public void releaseWaiters()

Used internally. Do not call directly. Use requestMutex and releaseMutex instead.

Release 1 (and only 1) waiter currently registered for the item.

Called by releaseMutex

Overrides:

releaseWaiters in class SEMState

See Also:

MutexState#releaseMutex()

isAvailable

public boolean isAvailable()

Returns:

true if the Mutex is currently not held by any owner.

requestMutex

public com.ibm.staf.STAFResult requestMutex(java.lang.String holder)
                                     throws java.lang.InterruptedException

Request exclusive ownership of the Mutex.
Calling thread will be blocked until access is granted.

Parameters:

holder -

Returns:

STAFResult.Ok, STAFResult.InvalidParam.

Throws:

java.lang.InterruptedException - if the waiting thread is interrupted.

releaseMutex

public com.ibm.staf.STAFResult releaseMutex(java.lang.String holder)

Release 1 (and only 1) Mutex waiter currently registered for the item.

Only the owner of the Mutex can release it.

Returns:

STAFResult.OK, STAFResult.NotSemaphoreOwner.