org.jdesktop.swinghelper.debug

Class EventDispatchThreadHangMonitor

java.lang.Object

java.awt.EventQueue

org.jdesktop.swinghelper.debug.EventDispatchThreadHangMonitor

public final class EventDispatchThreadHangMonitor
extends EventQueue

Monitors the AWT event dispatch thread for events that take longer than a certain time to be dispatched.

The principle is to record the time at which we start processing an event, and have another thread check frequently to see if we're still processing. If the other thread notices that we've been processing a single event for too long, it prints a stack trace showing what the event dispatch thread is doing, and continues to time it until it finally finishes.

This is useful in determining what code is causing your Java application's GUI to be unresponsive.

The original blog can be found here
Automatically detecting AWT event dispatch thread hangs

Author:

Elliott Hughes

Advice, bug fixes, and test cases from Alexander Potochkin and Oleg Sukhodolsky.

https://swinghelper.dev.java.net/

Method Summary

Modifier and Type	Method and Description
protected void	dispatchEvent(AWTEvent event) Overrides EventQueue.dispatchEvent to call our pre and post hooks either side of the system's event dispatch code.
static EventDispatchThreadHangMonitor	getInstance()
long	getTimeout()
static void	initMonitoring() Sets up hang detection for the event dispatch thread.
void	setTimeout(long timeout)

Methods inherited from class java.awt.EventQueue

createSecondaryLoop, getCurrentEvent, getMostRecentEventTime, getNextEvent, invokeAndWait, invokeLater, isDispatchThread, peekEvent, peekEvent, pop, postEvent, push

Methods inherited from class java.lang.Object

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

Method Detail

initMonitoring

public static void initMonitoring()

Sets up hang detection for the event dispatch thread.

getInstance

public static EventDispatchThreadHangMonitor getInstance()

getTimeout

public long getTimeout()

setTimeout

public void setTimeout(long timeout)

dispatchEvent

protected void dispatchEvent(AWTEvent event)

Overrides EventQueue.dispatchEvent to call our pre and post hooks either side of the system's event dispatch code.

Overrides:

dispatchEvent in class EventQueue