alma.acs.gui.util.threadsupport

Class EDTExecutor

java.lang.Object

java.util.concurrent.AbstractExecutorService

alma.acs.gui.util.threadsupport.EDTExecutor

All Implemented Interfaces:

java.util.concurrent.Executor, java.util.concurrent.ExecutorService

public class EDTExecutor
extends java.util.concurrent.AbstractExecutorService

EDTExecutor executes tasks in the swing event dispatcher thread (EDT).

EDTExecutor is a helper that allows to submit tasks to the EDT like SwingUtilities.invokeLater(Runnable) does. The advantage is that it handles the case of executing the code from inside or outside of the EDT in a transparent way.
In the same way, EDTExecutor allows to run commands synchronously inside the EDT in the same way SwingUtilities.invokeAndWait(Runnable) does.

SwingWorker has something in common with EDTExecutor but it is too heavy and for most applications we don't need such a complexity.

We don't really need EDTExecutor to be a ExecutorService because it is very easy but in future we might want to extend by adding more features (without reaching the same completeness of SwingWorker of course).

Life cycle methods are kept easy because this class does not manage the life cycle of the EDT. In this perspective, and to avoid useless blocking due to synchronization, EDTExecutor does not keep track of tasks scheduled to be run and not yet executed (@see shutdownNow().

Since:

ACS 10.2

Author:

acaproni

Field Summary

Fields

Modifier and Type	Field and Description
protected boolean	hasBeenShutdown A flag set is the executor has been shut down.

Method Summary

Modifier and Type	Method and Description
boolean	awaitTermination(long timeout, java.util.concurrent.TimeUnit unit)
void	execute(java.lang.Runnable command) Executes the passed command in the EDT.
void	executeSync(java.lang.Runnable command) Execute the passed command in the EDT synchronously.
static EDTExecutor	instance()
boolean	isShutdown()
boolean	isTerminated()
void	shutdown() Shuts down the Executor (and not the swing EDT): EDTExecutor will not submit other tasks to the EDT.
java.util.List<java.lang.Runnable>	shutdownNow() Shuts down the Executor (and not the swing EDT): EDTExecutor will not submit other tasks to the EDT.

Methods inherited from class java.util.concurrent.AbstractExecutorService

invokeAll, invokeAll, invokeAny, invokeAny, newTaskFor, newTaskFor, submit, submit, submit

Methods inherited from class java.lang.Object

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

Field Detail

hasBeenShutdown

protected volatile boolean hasBeenShutdown

A flag set is the executor has been shut down.

Method Detail

instance

public static EDTExecutor instance()

Returns:

The singleton

shutdown

public void shutdown()

Shuts down the Executor (and not the swing EDT): EDTExecutor will not submit other tasks to the EDT.

shutdownNow

public java.util.List<java.lang.Runnable> shutdownNow()

Shuts down the Executor (and not the swing EDT): EDTExecutor will not submit other tasks to the EDT.

Returns:

null because this executor does not have a queue of tasks to submit.

isShutdown

public boolean isShutdown()

isTerminated

public boolean isTerminated()

awaitTermination

public boolean awaitTermination(long timeout,
                                java.util.concurrent.TimeUnit unit)
                         throws java.lang.InterruptedException

Throws:

java.lang.InterruptedException

execute

public void execute(java.lang.Runnable command)

Executes the passed command in the EDT.

It can be called from inside or outside of the swing event dispatcher thread.

Parameters:

command - The command to execute in the EDT

executeSync

public void executeSync(java.lang.Runnable command)
                 throws java.lang.reflect.InvocationTargetException,
                        java.lang.InterruptedException

Execute the passed command in the EDT synchronously.

It can be called from inside or outside of the swing event dispatcher thread.

Parameters:

command - The command to execute in the EDT

Throws:

java.lang.reflect.InvocationTargetException - if an exception is thrown while running the command

java.lang.InterruptedException - if we're interrupted while waiting for the event dispatching thread to finish excecuting command.run()