//
//	Multiple Ball version of the Ball World Game
//	Described in Chapter 5 of
//	Understanding Object-Oriented Programming with Java
//	by Timothy A Budd
//	Published by Addison-Wesley
//
//	see ftp://ftp.cs.orst.edu/pub/budd/java/ReadMe.html
//	for further information
//

import java.awt.*;


public class MultiBallWorld extends Frame {

    public static void main (String [ ] args)
    {
	MultiBallWorld world = new MultiBallWorld (Color.red);
	world.show ();
    }

    private static final int FrameWidth = 600;
    private static final int FrameHeight = 400;
    private Ball [ ] ballArray;
    private static final int BallArraySize = 6;
    private int counter = 0;

    private MultiBallWorld (Color ballColor) {
	// constructor for new ball world
	// resize our frame
	setSize (FrameWidth, FrameHeight);
	setTitle ("Ball World");

	// initialize object data field
	ballArray = new Ball [ BallArraySize ];
	for (int i = 0; i < BallArraySize; i++) {
	    ballArray[i] = new Ball(10, 15, 5);
	    ballArray[i].setColor (ballColor);
	    ballArray[i].setMotion (3.0+i, 6.0-i);
	}
    }

    public void paint (Graphics g) {
	for (int i = 0; i < BallArraySize; i++) {
	    ballArray[i].paint (g);
				// then move it slightly
	    ballArray[i].move();
	    if ((ballArray[i].x() < 0) || (ballArray[i].x() > FrameWidth))
		ballArray[i].setMotion (-ballArray[i].xMotion(), ballArray[i].yMotion());
	    if ((ballArray[i].y() < 0) || (ballArray[i].y() > FrameHeight))
		ballArray[i].setMotion (ballArray[i].xMotion(), -ballArray[i].yMotion());
	}
				// finally, redraw the frame
	counter = counter + 1;
	if (counter < 2000) repaint(1);
	else System.exit(0);
    }
}