java做的小球弹跳小程序源码

package Parabola; import java.awt.*; import java.awt.event.ActionEvent; import java.awt.event.ActionListener; import java.awt.event.WindowAdapter; import java.awt.event.WindowEvent; import javax.swing.*; public class Parabola1 extends JFrame { private static final int width=1000; private static final int height=700; private int x=150,y=300;//小球的坐标 private int r=20;//小球的半径 private int a=1;//垂直位移改变量 private int b=10;//水平位移改变量 private int m=3;//垂直位移改变增量 private int btmH=650;//地板高度 private int left=0;//左边墙面的水平位置 private int right=975;//右边墙面的水平位置 private int i=0; public Parabola1(){ super("抛物线运动"); this.setBounds(200, 10, width, height); ParabolaPane pane=new ParabolaPane(); this.add(pane, "Center"); this.addWindowListener(new WindowAdapter(){ @Override public void windowClosing(WindowEvent e) { // TODO Auto-generated method stub System.exit(0); } }); this.setVisible(true); } class ParabolaPane extends JPanel{ public ParabolaPane(){ setSize(width, height); setVisible(true); Timer timer=new Timer(30,new TimerListener()); timer.start(); } protected void paintComponent(Graphics g){ super.paintComponent(g); Color c=g.getColor(); g.setColor(Color.red); g.fillOval(x, y, r, r); g.setColor(Color.BLUE); g.fillRect(right, 0, 20, 700); g.fillRect(left, 0, 20, 700); g.fillRect(0, btmH, 1000, 20); g.setColor(c); } public int getQy(){ if((y+r)>btmH){ y=btmH-20; a=-a; } if(b==0){ y=630; a=0; } a=a+m; y=y+a; return y; } public int getQx(){ if((x+r)>right||(x-r)<left){ b=b*(-1); } if((x+r)>right){ x=right-20; }else if((x-r)<left){ x=left+20; } if(y/((btmH-20)/10)==10){ if(i%100==0){ b=9*b/10; } } x=x+b; return x; } class TimerListener implements ActionListener{ public void actionPerformed(ActionEvent e) { x=getQx(); y=getQy(); i++; repaint(); System.out.println("i="+i+" a="+a+" b="+b+" x="+x+" y="+y+" y+r="+(y+r)); } } } public static void main(String arg[]){ Parabola1 para=new Parabola1(); } }