Java1.3.1 + (Jframe + Timer(swing) + Jmenu) = jframe quits!!

Question

Hi,
I have a program swing which draws polygons (nope, not 3d) on a JPanel in a JFrame.
I am not sure why, but my Timer (swing, not java.util) and Jmenu component somehow don't like each other.
My program works fine without the JMenu, or without the Timer, but as soon as I use both, the program fires up and closes immediately without any errors! (running jdb revealed nothing)
This only happens in java 1.3.1, <b>not 1.4</b>, but before I label this as a bug (which one shouldn't do too quickly!) perhaps someone round here can try this out and perhaps find my (silly) mistake, if it exists.
Thank you in advance,
Vilnis
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
import javax.swing.event.*;
public class Scene
public static void main(String[] args){
JFrame frame = new Display();
frame.addWindowListener(new Closer());
frame.setSize(640,480);
frame.show();
class Closer extends WindowAdapter
public void windowClosing(WindowEvent e){
//this is the only exiting command in the whole code
System.out.println("Exited properly");
System.exit(0);
class Display extends JFrame
Drawing graphics;
JPopupMenu sceneMenu;
MouseListener popupListener;
Display(){
graphics = new Drawing();
sceneMenu = popMenu();
popupListener = new PopupListener();
graphics.addMouseListener(popupListener);
getContentPane().add(graphics);
public JPopupMenu popMenu(){
JPopupMenu menu;
menu = new JPopupMenu();
/* one way to stop the problem is to comment out the next three
* lines, i.e. remove the JMenu component.
* the other 'solution' is to comment out line 127 (timer)
JMenu subMenu = new JMenu("subMenu");
subMenu.add(new JMenuItem("subButton1"));
menu.add(subMenu);
menu.add(new JMenuItem("button1"));
menu.addSeparator();
menu.add(new JMenuItem("button2"));
return menu;
/*this class has nothing to do with the problem -
I tried commenting it out. */
class PopupListener extends MouseAdapter
public void mousePressed(MouseEvent e){
maybeShowPopup(e);
public void mouseReleased(MouseEvent e){
maybeShowPopup(e);
private void maybeShowPopup(MouseEvent e){
if (e.isPopupTrigger()){
sceneMenu.show(e.getComponent(),
e.getX(), e.getY());
class Drawing extends JPanel implements ActionListener
private Polygon drawPoly[];
private BouncyPolygon bPoly[];
private Timer reDraw;
Drawing(){
//define 2 polygons
int axs[] = {0,320,30, 50, 145};
int ays[] = {0, 60, 100, 90, 200};
int bxs[] = {50,370,80, 80, 220};
int bys[] = {50, 110, 150, 56, 78};
drawPoly = new Polygon[2];
bPoly = new BouncyPolygon[2];
drawPoly[0] = new Polygon(axs, ays, 5);
drawPoly[1] = new Polygon(bxs, bys, 5);
/* the bouncyPolygon class was originally supposed to have
* it's own timer, but I took it out to see whether this
* was something to do with the problem.
* The 'this' (Drawing) class gets passed so getWidth and
* getHeight can be used to bounce the individual points of
* the polygons of walls even if the window is resized.
* the first two params specify x and y coordinates, the third
* specifies the number of points the polygon has,
* the forth param is the drawing jPanel
* and the last one is the speed of movement.
bPoly[0] = new BouncyPolygon(axs, ays, 5, this, 4);
bPoly[1] = new BouncyPolygon(bxs, bys, 5, this, 7);
/* set timer to redraw screen every 30ms
* (the only timer in the whole program)
reDraw = new Timer(30,this);
reDraw.start();
public void actionPerformed(ActionEvent e)
for (int i = 0; i <bPoly.length; i++){
//move polygons
bPoly.move();
//update coordinates
drawPoly[i].xpoints = bPoly[i].getXs();
drawPoly[i].ypoints = bPoly[i].getYs();
repaint();
public void paintComponent(Graphics g){ 
super.paintComponent(g);
Graphics2D g2 = (Graphics2D) g;
g2.setPaint(
new GradientPaint(0,0,Color.red, 320, 240, Color.green, true));
g2.draw(drawPoly[0]);
g2.setPaint(
new GradientPaint(0,0,Color.blue, 320, 240, Color.yellow, true));
g2.draw(drawPoly[1]);
class BouncyPolygon
private int pointCount;
//coordinates
private int xs[], ys[];
//direction flags for each point
private int dirX[], dirY[];
//speed
private int moveSize;
private JPanel j;
BouncyPolygon(int xpoints[], int ypoints[], int npoints, JPanel jp,
int moveAmount){
if (xpoints.length == npoints && ypoints.length == npoints){
j = jp;
pointCount = npoints;
xs = xpoints;
ys = ypoints;
moveSize = moveAmount;
dirX = new int[npoints];
dirY = new int[npoints];
//initialize direction array
for (int i = 0; i < npoints; i++){
dirX[i] = 1;
dirY[i] = 1;
} else{
System.out.println(
"Array size does no equal polygon point count!\n");
System.exit(1);
//move the polygons (and bounce of Walls)
public void move(){
for (int i = 0; i < pointCount; i++){
if (dirX[i] == 1 && xs[i] >= j.getWidth() - (moveSize - 1)||
dirX[i] == -1 && xs[i] <= (moveSize - 1)){
dirX[i] *= -1;
xs[i] += (int) (dirX[i] * moveSize);
if (dirY[i] == 1 && ys[i] >= j.getHeight() - (moveSize - 1) ||
dirY[i] == -1 && ys[i] <= (moveSize - 1)){
dirY[i] *= -1;
ys[i] += (int) (dirY[i] * moveSize);
public int[] getXs(){
return xs;
public int[] getYs(){
return ys;

Answer 1

This code should work now ;)
As I said before, the problem only comes up with java 1.3.1 and not 1.4.
Ok, I don't know about other versions.
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
import javax.swing.event.*;
public class Scene
public static void main(String[] args){
JFrame frame = new Display();
frame.addWindowListener(new Closer());
frame.setSize(640,480);
frame.show();
class Closer extends WindowAdapter
public void windowClosing(WindowEvent e){
//this is the only exiting command in the whole code
System.out.println("Exited properly");
System.exit(0);
class Display extends JFrame
Drawing graphics;
JPopupMenu sceneMenu;
MouseListener popupListener;
Display(){
graphics = new Drawing();
sceneMenu = popMenu();
popupListener = new PopupListener();
graphics.addMouseListener(popupListener);
getContentPane().add(graphics);
public JPopupMenu popMenu(){
JPopupMenu menu;
menu = new JPopupMenu();
/* one way to stop the problem is to comment out the next three
* lines, i.e. remove the JMenu component.
* the other 'solution' is to comment out line 127 (timer)
JMenu subMenu = new JMenu("subMenu");
subMenu.add(new JMenuItem("subButton1"));
menu.add(subMenu);
menu.add(new JMenuItem("button1"));
menu.addSeparator();
menu.add(new JMenuItem("button2"));
return menu;
/*this class has nothing to do with the problem -
I tried commenting it out. */
class PopupListener extends MouseAdapter
public void mousePressed(MouseEvent e){
maybeShowPopup(e);
public void mouseReleased(MouseEvent e){
maybeShowPopup(e);
private void maybeShowPopup(MouseEvent e){
if (e.isPopupTrigger()){
sceneMenu.show(e.getComponent(),
e.getX(), e.getY());
class Drawing extends JPanel implements ActionListener
private Polygon drawPoly[];
private BouncyPolygon bPoly[];
private Timer reDraw;
Drawing(){
//define 2 polygons
int axs[] = {0,320,30, 50, 145};
int ays[] = {0, 60, 100, 90, 200};
int bxs[] = {50,370,80, 80, 220};
int bys[] = {50, 110, 150, 56, 78};
drawPoly = new Polygon[2];
bPoly = new BouncyPolygon[2];
drawPoly[0] = new Polygon(axs, ays, 5);
drawPoly[1] = new Polygon(bxs, bys, 5);
/* the bouncyPolygon class was originally supposed to have
* it's own timer, but I took it out to see whether this
* was something to do with the problem.
* The 'this' (Drawing) class gets passed so getWidth and
* getHeight can be used to bounce the individual points of
* the polygons of walls even if the window is resized.
* the first two params specify x and y coordinates, the third
* specifies the number of points the polygon has,
* the forth param is the drawing jPanel
* and the last one is the speed of movement.
bPoly[0] = new BouncyPolygon(axs, ays, 5, this, 4);
bPoly[1] = new BouncyPolygon(bxs, bys, 5, this, 7);
/* set timer to redraw screen every 30ms
* (the only timer in the whole program)
reDraw = new Timer(30,this);
reDraw.start();
public void actionPerformed(ActionEvent e)
for (int i = 0; i <bPoly.length; i++){
//move polygons
bPoly.move();
//update coordinates
drawPoly[i].xpoints = bPoly[i].getXs();
drawPoly[i].ypoints = bPoly[i].getYs();
repaint();
public void paintComponent(Graphics g){
super.paintComponent(g);
Graphics2D g2 = (Graphics2D) g;
g2.setPaint(
new GradientPaint(0,0,Color.red, 320, 240, Color.green, true));
g2.draw(drawPoly[0]);
g2.setPaint(
new GradientPaint(0,0,Color.blue, 320, 240, Color.yellow, true));
g2.draw(drawPoly[1]);
class BouncyPolygon
private int pointCount;
//coordinates
private int xs[], ys[];
//direction flags for each point
private int dirX[], dirY[];
//speed
private int moveSize;
private JPanel j;
BouncyPolygon(int xpoints[], int ypoints[], int npoints, JPanel jp,
int moveAmount){
if (xpoints.length == npoints && ypoints.length == npoints){
j = jp;
pointCount = npoints;
xs = xpoints;
ys = ypoints;
moveSize = moveAmount;
dirX = new int[npoints];
dirY = new int[npoints];
//initialize direction array
for (int i = 0; i < npoints; i++){
dirX[i] = 1;
dirY[i] = 1;
} else{
System.out.println(
"Array size does no equal polygon point count!\n");
System.exit(1);
//move the polygons (and bounce of Walls)
public void move(){
for (int i = 0; i < pointCount; i++){
if (dirX[i] == 1 && xs[i] >= j.getWidth() - (moveSize - 1)||
dirX[i] == -1 && xs[i] <= (moveSize - 1)){
dirX[i] *= -1;
xs[i] += (int) (dirX[i] * moveSize);
if (dirY[i] == 1 && ys[i] >= j.getHeight() - (moveSize - 1) ||
dirY[i] == -1 && ys[i] <= (moveSize - 1)){
dirY[i] *= -1;
ys[i] += (int) (dirY[i] * moveSize);
public int[] getXs(){
return xs;
public int[] getYs(){
return ys;