DiMartino

   public static void main(String args[])
   {
	   BallBounce4 frame = new BallBounce4();
	   frame.setSize(new Dimension(900, 900));
	   frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
	   frame.setVisible(true);

	   Timer timer = new Timer(10, new ActionListener(){

		@Override
		public void actionPerformed(ActionEvent arg0) {
			frame.repaint();
		}

	   });
	   timer.start();
   }