Canvas en applet de java

Cuando se hace clic sobre el applet, el canvas, que visualiza una figura pequeña, se mueve a la izquierda y
luego hacia la derecha.


package masterdavidjavabasico;

import java.applet.Applet;
import java.awt.*;
import java.awt.event.*;

/*
  <APPLET
      CODE=canvas.class
      WIDTH=400
      HEIGHT=200 >
  </APPLET>
*/

public class canvas extends java.applet.Applet implements MouseListener {

    graphicsCanvas gc;
    Button button1;

    public void init()
    {
        gc = new graphicsCanvas();
        gc.setSize(100, 100);
        add(gc);
        addMouseListener(this);
    }
   
    public void mousePressed(MouseEvent e){}

    public void mouseClicked(MouseEvent e)
    {
       for(int loop_index = 0; loop_index < 150; loop_index++){
           gc.setLocation(loop_index, 0);
       }
    }
    public void mouseReleased(MouseEvent e){}
    public void mouseEntered(MouseEvent e){}
    public void mouseExited(MouseEvent e){}
}

class graphicsCanvas extends java.awt.Canvas
{
    public void paint (Graphics g)
    {
        g.drawOval(10, 50, 40, 40);
        g.drawLine(10, 50, 50, 90);
        g.drawLine(50, 50, 10, 90);
    }
}