// main class
public MainClass {
  private GameCanvas canvas = new MyGameCanvas();


  public MainClass() {
    // start a thread that will run infinitely
	canvas.start();
  }
  
  // rest of the code
}


// the actual drawing class
public MyGameCanvas extends GameCanvas implements Runnable {


  public MyGameCanvas() {
    // instantiation code
  }
  
  public void start() {
    // do initialization
	
	// and then start a thread
	Thread runner = new Thread(this);
	runner.start();
  }
  
  private void run() {
  
    // or while(keeprunning = true) 
    // where keeprunning is an instance variable

    while(true) { 


      // checks if the game has reached 
      // some boundary states or special conditions
	  verifyGameState(); 


      // gets input from user and 
      // updates instance variables 
      // that describe the games elements

  	  checkUserInput(); 


      // paints elements on screen to reflect
      // the current game state using the current 
      // graphics object

	  updateGameScreen(getGraphics());


      // control the rate at which screen updates are done 

	  Thread.sleep(milliseconds); 
	}
  }
}