pinball.java

一些JAVA的小程序

//
//	PinBall class.  Extends Ball class
//
//	From Chapter 7 of
//	Understanging Object-Oriented Programming with Java
//	Written by Tim Budd
//	Published by Addison-Wesley Longman
//
//	See ftp://ftp.cs.orst.edu/pub/budd/java/ReadMe.html 
//	for further information
//

import java.awt.*;

public class PinBall extends Ball {
	
	public PinBall (int sx, int sy) 
	{
		super(sx, sy, 10);
			// start out moving (roughly) vertical
		setMotion (-2 + Math.random()/4, -15);
	}

	private double gravityEffect = 0.3;

	public void move ()
	{
		dy = dy + gravityEffect; // effect of gravity
		super.move();	// update the ball position
	}
}