e1617.java

java小程序

import java.awt.*;
import java.awt.event.*;
import java.applet.*;
import javax.swing.*;
public class E1617 extends JApplet implements ActionListener
{
private Color[] color={Color.red,Color.blue};
private int sleepTime=0;
private int count=-1;
private Color ballColor;
private int x,y;
private Timer timer;
private double R=200.0;
private double deta=0.0;
public void init()
{
timer=new Timer(200,this);
timer.start();
}
public void actionPerformed(ActionEvent e)
{ 
deta+=Math.PI/18;
x=250-(int)(R*Math.cos(deta));
y=250-(int)(R*Math.sin(deta));
sleepTime+=200;
repaint();
}

public void paint(Graphics g)
{
int x1,y1;
if(sleepTime%7200==0)
{
g.setColor(Color.white);
for(double deta1=0.0;deta1<2*Math.PI;deta1+=Math.PI/18)
{
x1=250-(int)(R*Math.cos(deta1));
y1=250-(int)(R*Math.sin(deta1));
g.fillOval(x1,y1,30,30);
}
int num=count+1;
count=(num)%2;
deta=0.0;
}
x=250-(int)(R*Math.cos(deta));
y=250-(int)(R*Math.sin(deta));
g.setColor(color[count]);
g.fillOval(x,y,30,30);

}

}