Name: dsR10051 Date: 10/17/2000



The method
protected void java.awt.Component.processFocusEvent(FocusEvent e)
is not called by event dispatch thread even if a FocusListener
object is registered via addFocusListener
(See JavaDoc for Component.processFocusEvent).

Here is a minimized test:
import java.awt.*;
import java.awt.event.*;

public class ComponentTest4 {
    public static void main (String[] args) {
        EventQueue eq = Toolkit.getDefaultToolkit().getSystemEventQueue();
        ChildComponent chcomponent = new ChildComponent();
        FocusEvent e = new FocusEvent(chcomponent, FocusEvent.FOCUS_LOST);
        DummyFocusListener cl = new DummyFocusListener();
        chcomponent.addFocusListener(cl);

        eq.postEvent(e);
        synchronized (chcomponent) {
            while(!chcomponent.focusEventProcessed) {
                try {
                    System.out.println("Waiting");
                    System.out.flush();

                    chcomponent.wait();

                    System.out.println("Done");
                    System.out.flush();
                } catch (InterruptedException ie) {
                    ie.printStackTrace();
                }
            }
        }
        System.exit(0);
    }
}

class ChildComponent extends Component {
    public ChildComponent() {
        super();
    }

    boolean focusEventProcessed = false;
    public synchronized void processFocusEvent(FocusEvent e) {
        focusEventProcessed = true;
        System.out.println("processFocusEvent called");
        System.out.flush();
        super.processFocusEvent(e);
        System.out.println("processFocusEvent done");
        System.out.flush();
        notifyAll();
    }
}

class DummyFocusListener extends FocusAdapter {
}

--- Output ---
%/net/sword/export3/JDK1.4.0beta-b36/solaris/bin/java -version
java version "1.4.0beta"
Java(TM) 2 Runtime Environment, Standard Edition (build 1.4.0beta-b36)
Java HotSpot(TM) Client VM (build 1.4beta-B36, mixed mode)
%/net/sword/export3/JDK1.4.0beta-b36/solaris/bin/java ComponentTest4
Waiting
^C
%

======================================================================