import java.applet.*;
import java.awt.*;

public class MoveBall extends Applet implements Runnable
{
	// Initialisierung der Variablen
	int x_pos = 10;		// x - Position des Balles
	int y_pos = 100;	// y - Position des Balles
	int radius = 20;	// Radius des Balles
	int moveBy = 1;		// amount to moveBy

	static final int WIDTH = 200;  // width of the canvas
	static final int HEIGTH = 200;	// height of the canvas

	public void init()
	{
		setBackground (Color.blue);
	}

	public void start ()
	{
		// Schaffen eines neuen Threads, in dem das Spiel läuft
		Thread th = new Thread (this);
		// Starten des Threads
		th.start ();
	}

	public void stop()
	{

	}

	public void destroy()
	{

	}

	public void run ()
	{
		
		Thread.currentThread().setPriority(Thread.MIN_PRIORITY);

		
		while (true)
		{
		
			if (x_pos >= WIDTH)
				moveBy = -1;
			if (x_pos <= 30)
				moveBy = 1;
			
			x_pos = x_pos + moveBy;

			repaint();

			try
			{
				Thread.sleep (20);
			}
			catch (InterruptedException ex)
			{
			}

			
			Thread.currentThread().setPriority(Thread.MAX_PRIORITY);
		}
	}


	public void paint (Graphics g)
	{
		g.setColor  (Color.red);

		g.fillOval (x_pos - radius, y_pos - radius, 2 * radius, 2 * radius);
	}

}