Name: rmT116609 Date: 03/26/2001


java version "1.3.0"
Java(TM) 2 Runtime Environment, Standard Edition (build 1.3.0-C)
Java HotSpot(TM) Client VM (build 1.3.0-C, mixed mode)


#
# HotSpot Virtual Machine Error, EXCEPTION_ACCESS_VIOLATION
# Please report this error at
# http://java.sun.com/cgi-bin/bugreport.cgi
#
# Error ID: 4F533F57494E13120E43505002D4
#

The above error occurs when a component overrides method
getCursor() and returns null.

Please the run program below and run the mouse over the
blue rectangle. This should cause HotSpot to crash.


import java.awt.*;
import java.awt.event.*;
import java.util.*;
import javax.swing.*;

public class CursorBug extends JLayeredPane {

   public static final int WEEK_DAY_WIDTH = 100;

   public static final int WEEK_END_WIDTH = 70;

   public static final int ROW_HEIGHT = 30;

   public CursorBug() {
   }

   public void paintComponent(Graphics g) {
      super.paintComponent(g);

      // Set our background to white
      g.setColor(Color.white);
      g.fillRect(0, 0, getMaximumWidth(), getMaximumHeight());

      paintDisarmed(g);
   }

   private void paintDisarmed(Graphics g) {
      // Paint the vertical divides between each day
      int h = getMaximumHeight();
      int x = 0;
      // Grey line
      g.setColor(Color.gray);
      for(int i = 0; i < 5; i++) {
         x += WEEK_DAY_WIDTH;
         g.drawLine(x, 0, x, h-1);
      }
      x += WEEK_END_WIDTH;
      g.drawLine(x, 0, x, h-1);
   }

   public Dimension getMinimumSize() {
      return new Dimension(WEEK_DAY_WIDTH, ROW_HEIGHT);
   }

   public Dimension getPreferredSize() {
      return new Dimension(getMaximumWidth(), ROW_HEIGHT * 15);
   }

   public Dimension getMaximumSize() {
      return new Dimension(getMaximumWidth(), getMaximumHeight());
   }

   public int getMaximumWidth() {
      return (WEEK_DAY_WIDTH * 5) + (WEEK_END_WIDTH * 2);
   }

   public int getMaximumHeight() {
      return ROW_HEIGHT * 24;
   }

   /**
    * Test
    */
   public static void main(String[] args) {
      try {
         UIManager.setLookAndFeel( UIManager.getSystemLookAndFeelClassName() );
      } catch (Exception e) {
         System.err.println("Couldn't use the system-platform look and feel: "+ e);
      }

      JFrame f = new JFrame("Cursor Bug");

      JPanel p = new JPanel(new BorderLayout());

      CursorBug ws = new CursorBug();

      // Add a Ribbon
      Ribbon r = new Ribbon();
      ws.add(r);
      r.setBounds(50, 50, 75, 75);

      JScrollPane jsp = new JScrollPane(ws,
         ScrollPaneConstants.VERTICAL_SCROLLBAR_AS_NEEDED,
         ScrollPaneConstants.HORIZONTAL_SCROLLBAR_AS_NEEDED);

      p.add(jsp, BorderLayout.CENTER);

      f.getContentPane().add(p);

      f.pack();
      f.show();
   }
}

class Ribbon extends JPanel {

   public Ribbon() {
   }

/**** THIS IS THE BUG !!!! ****/
   public Cursor getCursor() {
      return null;
   }
/*****************************/

   public void paintComponent(Graphics g) {
      super.paintComponent(g);

      g.setColor(Color.blue);
      Dimension d = getSize();
      g.fillRect(0, 0, d.width, d.height);
   }
}

/* eof */
(Review ID: 119262)
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