JDK: 1.2beta4-D
OS: Solaris, NT
Locale: ALL

In Solaris and Windows NT, jdk1.2beta4-D, Thread's method yield() will call
application dead. Following is a program to reproduce this bug.
========================CheckThread.java===================================
import java.awt.*;
import java.awt.event.*;
import java.io.*;

public class CheckThread implements ActionListener {
    static Button b1;
    static Button b2;
    boolean PAUSE = false;
    LittleThread myThread;

    public static void main(String args[]) {
new CheckThread();
    }

    public CheckThread() {
Frame f = new Frame("Check Thread");
f.setLayout(new BorderLayout());
b1 = new Button("pause ");
b1.addActionListener(this);
b2 = new Button("begin");
b2.addActionListener(this);
f.add(b2, BorderLayout.NORTH);
f.add(b1, BorderLayout.SOUTH);
f.pack();
f.show();
    }

    public void actionPerformed(ActionEvent e) {
if (e.getSource() == b1 && myThread != null) {
if (!PAUSE) {
PAUSE = true;
myThread.pause();
b1.setLabel("resume");
} else {
PAUSE = false;
myThread.resume();
b1.setLabel("pause ");
}
} else {
myThread = new LittleThread();
myThread.start();
b2.setEnabled(false);
}
    }

class LittleThread implements Runnable {
    
    Choice choice1;
    int itemCount = 0;
    boolean PAUSE = false;
    Thread driver = null;

    public LittleThread() {
        Frame f = new Frame("Check Choice");
        f.setLayout(new BorderLayout());
        choice1 = new Choice();
        f.add(choice1, BorderLayout.CENTER);
        f.pack();
        f.show();
    }

    public void start() {
if (driver == null) {
driver = new Thread(this, "");
driver.start();
}
    }

    public void pause() {
PAUSE = true;
    }

    public void resume() {
PAUSE = false;
    }

    public void run() {
        while (true) {
if (PAUSE) {
driver.yield();
continue;
}
            if (choice1 != null && itemCount < 40) {
                choice1.add("I am Choice, yes I am : " + itemCount * itemCount);
                itemCount ++;
            }
            if (itemCount >= 20 && choice1 != null && choice1.getItemCount() > 0) {
                choice1.removeAll();
                itemCount = 0;
            }
            try {
                Thread.sleep(1000);
            } catch (Exception ex) {
            }
        }
    }
}

}
================================================================================
java CheckThread
press button "begin" to start a thread
press button "pause" to pause it
application dead

jim.hu@prc 1998-05-04

This bug still exists in 1.2beta4-E. I think it should be
fixed in the next build.

jim.hu@prc 1998-05-13