Java -- 乒乓球 乒乓弹球游戏

import java.awt.Canvas;
import java.awt.Color;
import java.awt.Dimension;
import java.awt.Font;
import java.awt.Frame;
import java.awt.Graphics;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.event.KeyAdapter;
import java.awt.event.KeyEvent;
import java.awt.event.WindowAdapter;
import java.awt.event.WindowEvent;
import java.util.Random;

import javax.swing.Timer;

public class PinBall {

/**
* @param args
*/
//桌面长宽
private final int TABLE_WIDTH = 300;
private final int TABLE_HEIGHT = 400;
//球拍的垂直位置
private final int RACKET_Y = 340;
//球拍的高度和宽度
private final int RACKET_HEIGHT = 20;
private final int RACKET_WIDTH = 60;
//球大小
private final int BALL_SIZE = 16;
private Frame f = new Frame("PinBall");
Random rand = new Random();
//小球纵向的运行速度
private int ySpeed = 10;
private double xyRate = rand.nextDouble() - 0.5;
private int xSpeed = (int)(ySpeed*xyRate*2);
private int ballX = rand.nextInt(200) + 20;
private int ballY = rand.nextInt(10) + 20;
private int racketX = rand.nextInt(200);
private String shape = "";
Timer timer;
private boolean isLose = false;
private MyCanvas tableArea = new MyCanvas();

public void init()
{
tableArea.setPreferredSize(new Dimension(TABLE_WIDTH, TABLE_HEIGHT));
f.add(tableArea);
KeyAdapter keyProcessor = new KeyAdapter() {
public void keyPressed(KeyEvent ke)
{
if( ke.getKeyCode() == KeyEvent.VK_LEFT )
{
if( racketX > 0 )
racketX -= 10;
}
if( ke.getKeyCode() == KeyEvent.VK_RIGHT )
{
if( racketX < TABLE_WIDTH - RACKET_WIDTH )
racketX += 10;
}
}
};
f.addKeyListener(keyProcessor);
tableArea.addKeyListener(keyProcessor);

ActionListener taskPerformer = new ActionListener() {
@Override
public void actionPerformed(ActionEvent e) {
// TODO Auto-generated method stub
if( ballX <= 0 || ballX >= TABLE_WIDTH-BALL_SIZE )
{
xSpeed = -xSpeed;
}
if( ballY>= RACKET_Y - BALL_SIZE &&
(ballX < racketX || ballX > racketX + RACKET_WIDTH))
{
timer.stop();
isLose = true;
tableArea.repaint();
}
else if( ballY <= 0 ||
(ballY >= RACKET_Y - BALL_SIZE
&& ballX > racketX && ballX <= racketX + RACKET_WIDTH) )
{
ySpeed = -ySpeed;
}
ballY += ySpeed;
ballX += xSpeed;
tableArea.repaint();
}
};

f.addWindowListener(new WindowAdapter() {
public void windowClosing(WindowEvent e)
{
System.exit(0);
}
});
timer = new Timer(100, taskPerformer);
timer.start();
f.pack();
f.setVisible(true);

}

public static void main(String[] args) {
// TODO Auto-generated method stub
new PinBall().init();
}

class MyCanvas extends Canvas
{
public void paint(Graphics g)
{
if( isLose )
{
g.setColor(new Color(255, 0, 0));
g.setFont(new Font("Times", Font.BOLD, 30));
g.drawString("Game Over", 50, 200);
}
else
{
g.setColor(new Color(240, 240, 80));
g.fillOval(ballX, ballY, BALL_SIZE, BALL_SIZE);
g.setColor(new Color(80, 80, 200));
g.fillRect(racketX, RACKET_Y, RACKET_WIDTH, RACKET_HEIGHT);
}
}
}

}