Name: dsC58869 Date: 11/11/98



The method Toolkit.removeAWTEventListener(AWTEventListener listener) can not remove
the twice added listener from receiving dispatched AWTEvents.

==== Here is the test demonstrating the bug ====
import java.awt.*;
import java.awt.event.*;

public class Test {
    public static void main (String args[]) {
Toolkit toolkit = Toolkit.getDefaultToolkit();
EventQueue systemQueue = toolkit.getSystemEventQueue();
Component button = new Button("Button");
DummyAWTEventListener al = new DummyAWTEventListener(button);

// add twice
toolkit.addAWTEventListener(al, AWTEvent.COMPONENT_EVENT_MASK);
toolkit.addAWTEventListener(al, AWTEvent.COMPONENT_EVENT_MASK);
// remove twice
toolkit.removeAWTEventListener(al);
toolkit.removeAWTEventListener(al);



DummyAWTEvent awtEvent = new DummyAWTEvent(button,
ComponentEvent.COMPONENT_FIRST);
systemQueue.postEvent(awtEvent);
try {
Thread.sleep(2000);
} catch (Exception e) {
e.printStackTrace();
}
System.out.println(al.changed);
System.out.println(al.changedtwice);
if (!al.changed && !al.changedtwice) {
System.out.println("OKAY");
} else {
System.out.println("Failed");
}
System.exit(0);
    }
}

class DummyAWTEventListener implements AWTEventListener {
    Object sync;
    public DummyAWTEventListener (Object obj) {
sync = obj;
    }

    boolean changed = false;
    boolean changedtwice = false;
    public void eventDispatched(AWTEvent e){
if(sync == e.getSource()) {
if(changed) changedtwice = true;
else changed = true;
}
    }

}
class DummyAWTEvent extends AWTEvent {
    public DummyAWTEvent(Object source, int id) {
     super(source, id);
    }
}

==== Here is the output of the test ====
%java -fullversion
java full version "JDK-1.2fcs-R"
%java Test
true
false
Failed

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 Justification:
The method should work properly

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