Name: boT120536 Date: 11/09/2000


faun:~>java -version
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)

If the VM is running and ctrl-alt-delete happens (perhaps screensaver
also), the entire video context is affected. Once the desktop is restored,
drawstring seems to take much longer to generate results. This could be a
duplicate of Bug Id 4282147.


This application demonstrates the effect:
-------------------------------------------------------------
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
/**
 * Usage: execute java Gui, and click on the Repaint Canvas button many times
 * Once a sufficient sample is achieved, press the Reset Counter button
 * and hit CTRL-ALT-DELETE and the CANCEL on your Windows NT machine.
 * Repeat the sequence of Repaint Canvas presses and observe that the new
 * average is higher than the old one (stored in the 'Reset' button)
 **/
public class Gui extends JFrame {
  MyCanvas canvas;
  JButton resetButton;

  /** Build the GUI */
  public Gui ()
  {
    super( "Test GUI" );

    canvas = new MyCanvas();
    JButton repaintButton = new JButton("Repaint Canvas");
    repaintButton.addActionListener( new ActionListener() {
public void actionPerformed( ActionEvent evt )
{
canvas.repaint();
}
      });

    resetButton = new JButton("Reset counter");
    resetButton.addActionListener( new ActionListener() {
public void actionPerformed( ActionEvent evt )
{
resetButton.setText("Previous Avg = " + canvas.getAvg() );
canvas.resetAvg();
}
      });

    getContentPane().add( "North", resetButton );
    getContentPane().add( "Center", canvas );
    getContentPane().add( "South", repaintButton );

    addWindowListener(new WindowAdapter() {
public void windowClosing(WindowEvent e) {
System.exit(0);
}
      });
  }

  public static void main( String[] args )
  {
    Gui gui = new Gui();
    gui.pack();
    gui.setVisible(true);
  }

  private class MyCanvas extends Canvas
  {
    int reps;
    long sum;

    public MyCanvas()
    {
      setSize( 200, 100 );
      resetAvg();
    }

    public int getAvg()
    {
      if (reps == 0)
return 0;
      else
return (int)(sum / reps);
    }

    public void resetAvg()
    {
      reps = 0;
      sum = 0;
    }

    public void paint( Graphics g )
    {
      long time = System.currentTimeMillis();

      Dimension d = getSize();

      Color c = g.getColor();
      g.setColor( new Color(128,0,128,128) );
      g.fillOval(0,0,d.width, d.height);
      g.drawString("Hello world", d.width/2, d.height/2);

      g.setColor(c);

      System.out.print("Paint took " + (System.currentTimeMillis()-time) + " ms");
      sum += System.currentTimeMillis() - time;
      reps++;

      System.out.println(",\t Average = " + getAvg() + " ms");
    }
  }
}
(Review ID: 111929)
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