net.lecousin.framework.concurrent.async

Class LockPoint<TError extends Exception>

java.lang.Object

net.lecousin.framework.concurrent.async.AbstractLock<TError>

net.lecousin.framework.concurrent.async.LockPoint<TError>

Type Parameters:

TError - type of exception it may raise

All Implemented Interfaces:

Cancellable, IAsync<TError>

public class LockPoint<TError extends Exception>
extends AbstractLock<TError>

A LockPoint is similar to a mutual exclusion, but can be locked and unlocked by any thread.
For example, a first thread can lock it, and a second thread (after some processing is done) can unlock it.
A LockPoint can also be seen as a SynchronizationPoint but reusable.
When a thread calls the lock method:

• if the lock point is not yet locked it becomes locked and the calling thread can continue working, and must call the method unlock once done.
• if the lock point is already locked, the calling thread is paused, waiting for the lock point to be unlocked.

If several threads are waiting for the lock point to be unlocked:

• Only one is resume and obtain the lock, the others are still paused
• The order the threads are resumed is undetermined, meaning it is not necessarily in the order they called the lock method

Field Summary

Fields inherited from class net.lecousin.framework.concurrent.async.AbstractLock

cancel, error, listeners

Constructor Summary

Constructors

Constructor and Description
LockPoint()

Method Summary

Modifier and Type	Method and Description
void	block(long timeout) Pause the current thread to wait for this asynchronous unit to be unblocked.
boolean	blockPauseCondition() Return true if blockPause should still block.
boolean	isDone() Return true if unblocked (success or cancelled).
void	lock() Request the lock.
void	onDone(Runnable r) Call listener when unblocked (whatever the result is successful, has error or is cancelled).
void	unlock() Release the lock.

Methods inherited from class net.lecousin.framework.concurrent.async.AbstractLock

cancel, error, getAllListeners, getCancelEvent, getError, hasError, isCancelled

Methods inherited from class java.lang.Object

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

Methods inherited from interface net.lecousin.framework.concurrent.async.IAsync

blockException, blockPause, blockThrow, forwardIfNotSuccessful, isSuccessful, logListenerError, onCancel, onDone, onDone, onDone, onDone, onDone, onDone, onError, onErrorOrCancel, onSuccess, thenDoOrStart, thenDoOrStart, thenDoOrStart, thenStart, thenStart, thenStart, thenStart, thenStart, thenStart, toAsyncSupplier

Constructor Detail

LockPoint

public LockPoint()

Method Detail

lock

public void lock()

Request the lock. If it is already locked this method will block until it become unblocked and the lock has been obtained.

unlock

public void unlock()

Release the lock.

Specified by:

unlock in class AbstractLock<TError extends Exception>

isDone

public boolean isDone()

Description copied from interface: IAsync

Return true if unblocked (success or cancelled).

blockPauseCondition

public boolean blockPauseCondition()

Description copied from interface: IAsync

Return true if blockPause should still block.

onDone

public void onDone(Runnable r)

Description copied from interface: IAsync

Call listener when unblocked (whatever the result is successful, has error or is cancelled).

block

public void block(long timeout)

Description copied from interface: IAsync

Pause the current thread to wait for this asynchronous unit to be unblocked.