Name: dsC58869 Date: 09/10/99



The java.awt.Component.getListeners(Class listenerType) method always
returns null if listenerType is an java.beans.PropertyChangeListener.
Java Doc says:
    /**
     * Return an array of all the listeners that were added to the Component
     * with addXXXListener(), where XXX is the name of the
     * <code>listenerType</code>
     * argument. For example, to get all of the MouseListeners for the
     * given Component <code>c</code>, one would write:
     * <pre>
     * MouseListener[] mls = (MouseListener[])
     * (c.getListeners(MouseListener.class))
     * </pre>
     * If no such listener list exists, then an empty array is returned.
     *
     * @param listenerType Type of listeners requested
     * @returns an array of all listeners added to this Component using
     * addXXXListener, or an empty array if no such listeners have been
     * added to this Component.
     * @since 1.3
     */

PropertyChangeListener extends java.util.EventListener and can be added
to Component by addPropertyChangeListener(PropertyChangeListener listener) and
addPropertyChangeListener(String propertyName, PropertyChangeListener listener)
mehods, so getListener should process it correctly.

Here is a minimized test:
--- ComponentTest.java ---
import java.awt.*;
import java.beans.*;
import java.util.*;
public class ComponentTest {
    public static void main (String[] args) {
        Canvas c = new Canvas();
        PropertyChangeListener pcl = new MyPropertyChangeListener();
        c.addPropertyChangeListener(pcl);
        EventListener[] l = c.getListeners(PropertyChangeListener.class);
        System.out.println(l.length);
        if (l.length == 1)
            System.out.println("OKAY");
        else
            System.out.println("FAILED");
    }
}

--- Output ---
%java -version
java version "1.3beta"
Java(TM) 2 Runtime Environment, Standard Edition (build 1.3beta-O)
Java(TM) HotSpot Client VM
(build 1.3beta-O-release, 1.3beta-O-release, interpreted mode)
%java ComponentTest
0
FAILED

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