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


public class BouncerWouter extends Applet implements Runnable
{


   	private boolean keepGoing;
    private Graphics g;
    private int x = 7, xChange = 7;
    private int y = 0, yChange = 2;
    private int diameter = 10;
    private int rectLeftX = 0, rectRightX = 100;
    private int rectTopY = 0, rectBottomY = 100;
    private Thread bouncerdraad = null;


   public void start()
   {
	   keepGoing = true;
	   if(bouncerdraad == null)
	   {
		   bouncerdraad = new Thread(this, "bouncer");

		   bouncerdraad.start();


	   }



   }


	public void paint(Graphics g)
	{

					g.setColor(Color.red);
		            g.fillOval (x, y, diameter, diameter);

		            if (x + xChange <= rectLeftX)
		                xChange = -xChange;
		            if (x + xChange >= rectRightX)
		                xChange = -xChange;

		            if (y + yChange <= rectTopY)
		                yChange = -yChange;
		            if (y + yChange >= rectBottomY)
		                yChange = -yChange;

		            x = x + xChange;
		            y = y + yChange;






	}


    public void run()		// deze methode laat de thread draaien
    {

        while (keepGoing)
        {

				repaint();
//onderstaande code zorgt voor een vertragingseffect anders gaat het balletje veel te snel
            try {
                Thread.sleep(50);	// de thread van de stuiterende bal slaapt 50 ms
                					// hierdoor krijgt de thread van de gebruikersinterface
                					// wat processortijd om te draaien
            }
            catch (InterruptedException e) {
                System.err.println("sleep exception");

            }


        }
    }




	public void stop()
	{
		keepGoing = false;

	}


}