de.ipcon.gui

Class FocusSnitch

java.lang.Object

de.ipcon.gui.FocusSnitch

All Implemented Interfaces:

java.beans.PropertyChangeListener, java.util.EventListener

public class FocusSnitch
extends java.lang.Object
implements java.beans.PropertyChangeListener

A utility class for debugging focus-related issues in our Swing application.

This class implements PropertyChangeListener to "snitch" on the KeyboardFocusManager. It listens for changes in focus-related properties and logs detailed information about these events, including which component gained focus and the window it belongs to. This is especially useful for diagnosing problems with focus traversal or components unexpectedly losing focus. The logger is configured to log at "INFO" level and includes a stack trace (even though it's typically uninteresting as it comes from the EDT) to provide context for the log entry.

Constructor Summary

Constructors

Constructor and Description
FocusSnitch() Constructs a new `FocusSnitch` and registers it as a PropertyChangeListener with the current "KeyboardFocusManager".

Method Summary

Modifier and Type	Method and Description
void	propertyChange(java.beans.PropertyChangeEvent pce) Invoked when a focus-related property changes.

Methods inherited from class java.lang.Object

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

Constructor Detail

FocusSnitch

public FocusSnitch()

Constructs a new `FocusSnitch` and registers it as a PropertyChangeListener with the current "KeyboardFocusManager".

This ensures that `propertyChange` will be invoked whenever a focus property changes within the application's Swing environment.

Method Detail

propertyChange

public void propertyChange(java.beans.PropertyChangeEvent pce)

Invoked when a focus-related property changes.

This method filters out events where the new value is null and then logs the property name and the new value. It uses the tool method FormElementI.toDebugName(Object) to format the component or window for a more readable log message. A stack trace is included to help trace the event's origin, even though it typically originates from the Event Dispatch Thread (EDT) and might not reveal a great deal of useful information.

Specified by:

propertyChange in interface java.beans.PropertyChangeListener

Parameters:

pce - The PropertyChangeEvent describing the property change.