import java.awt.*;

public abstract class AnimationApplet 
    extends java.applet.Applet 
    implements java.lang.Runnable {
  public void start() {
    animationThread = new Thread(this);
    animationThread.start();
  }    
  public void stop() {
    animationThread = null; 
  }  
  public void run() {
    while (Thread.currentThread() == animationThread) {
      try { 
        Thread.currentThread().sleep(delay); 
      } catch (InterruptedException e){}     
      repaint();
    }
  }
  final public void setDelay(int delay) {
    this.delay = delay; 
  }  
  final public int getDelay() {
    return delay; 
  } 
  /** The animation thread */ 
  protected Thread animationThread;
  /** The interval between two consecutive frames 
      in milliseconds */
  protected int delay = 100;     
}