com.lf.commons.gui

Class CommonsSwingWorker

java.lang.Object

com.lf.commons.gui.CommonsSwingWorker

public abstract class CommonsSwingWorker
extends java.lang.Object

This is the 3rd version of SwingWorker (also known as SwingWorker 3), an abstract class that you subclass to perform GUI-related work in a dedicated thread. For instructions on using this class, see:

http://java.sun.com/docs/books/tutorial/uiswing/misc/threads.html

Note that the API changed slightly in the 3rd version: You must now invoke start() on the SwingWorker after creating it.

The second constructor method receives the desired priority of the Swing Worker thread. You may use values between Thread.MIN_PRIORITY and Thread.MAX_PRIORITY here. For example use this functionality if you encounter problems with GUI updates while SwingWorker threads are running. You may then decrease the priority of these threads to give the GUI more chances to refresh.

Since:

1.5

Version:

$Revision: 1.4 $, $Date: 2012/12/28 11:44:25 $

Author:

Axel Schwolow

Constructor Summary

Constructors

Constructor and Description
CommonsSwingWorker() Start a thread that will call the construct method and then exit.
CommonsSwingWorker(int priority) Start a thread that will call the construct method and then exit.

Method Summary

Methods

Modifier and Type	Method and Description
abstract java.lang.Object	construct() Compute the value to be returned by the get() method.
static CommonsSwingWorker	createWorker(int priority, java.lang.Runnable preupdater, int pretimeout, java.lang.Runnable task, java.lang.Runnable postupdater) Creates a new worker instance with a task (separate thread) and GUI update code blocks (EDT).
void	finished() Called on the event dispatching thread (not on the worker thread) after the construct method has returned.
java.lang.Object	get() Return the value created by the construct method.
protected java.lang.Object	getValue() Get the value produced by the worker thread, or null if it hasn't been constructed yet.
void	interrupt() A new method that interrupts the worker thread.
void	join() Waits until the worker has been finished.
void	start() Start the worker thread.

Methods inherited from class java.lang.Object

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

Constructor Detail

CommonsSwingWorker

public CommonsSwingWorker()

Start a thread that will call the construct method and then exit.

Since:

1.5

CommonsSwingWorker

public CommonsSwingWorker(int priority)

Start a thread that will call the construct method and then exit.

The second constructor method receives the desired priority of the Swing Worker thread. You may use values between Thread.MIN_PRIORITY and Thread.MAX_PRIORITY here. For example use this functionality if you encounter problems with GUI updates while SwingWorker threads are running. You may then decrease the priority of these threads to giv e the GUI more chances to refresh.

Parameters:

priority - Value between Thread.MIN_PRIORITY and Thread.MAX_PRIORITY

Since:

1.5

Method Detail

getValue

protected java.lang.Object getValue()

Get the value produced by the worker thread, or null if it hasn't been constructed yet.

Returns:

Value produced by the worker thread

Since:

1.5

construct

public abstract java.lang.Object construct()

Compute the value to be returned by the get() method.

Returns:

Value produced by the get() method

Since:

1.5

finished

public void finished()

Called on the event dispatching thread (not on the worker thread) after the construct method has returned.

Since:

1.5

interrupt

public void interrupt()

A new method that interrupts the worker thread. Call this method to force the worker to stop what it's doing.

Since:

1.5

get

public java.lang.Object get()

Return the value created by the construct method. Returns null if either the constructing thread or the current thread was interrupted before a value was produced.

Returns:

the value created by the construct method

Since:

1.5

start

public void start()

Start the worker thread.

Since:

1.5

join

public void join()

Waits until the worker has been finished.

Throws:

java.lang.IllegalStateException - If called from EDT

Since:

1.6

createWorker

public static CommonsSwingWorker createWorker(int priority,
                              java.lang.Runnable preupdater,
                              int pretimeout,
                              java.lang.Runnable task,
                              java.lang.Runnable postupdater)

Creates a new worker instance with a task (separate thread) and GUI update code blocks (EDT).

The worker is NOT started here. The pre-update timeout can be used to keep the pre-update code from being exeucted for a while (e.g. 2 seconds). If the task has been finished before the timeout is reached then the pre-update code will not be executed at all. This helps to avoid window flickering caused by the unnecessary (de)activation of GUI components.

Parameters:

priority - Value between Thread.MIN_PRIORITY and Thread.MAX_PRIORITY

preupdater - Code to disable the GUI executed by EDT (optional)

pretimeout - Milliseconds to wait before the pre-update code is executed, 0=immediately

task - Code to be executed by a separate thread (required)

postupdater - Code to be executed by EDT finally (optional)

Returns:

The worker

Since:

1.6