import java.applet.Applet;

import java.awt.Color;

import java.awt.Graphics;

import java.util.Random;

public class zhang extends Applet {

int x,y; //圆的位置

int W_H; //圆的大小

int R,G,B; //圆的颜色

Random rd = new Random();

public void init(){

this.resize(400, 300);

}

public void paint(Graphics g){

while ( true ){

W_H = rd.nextInt(100);

x = rd.nextInt(this.getWidth());

y = rd.nextInt(this.getHeight());

R = rd.nextInt(255);

G = rd.nextInt(255);

B = rd.nextInt(255);

g.setColor(Color.white);

g.fillRect(0,0,this.getWidth(),this.getHeight());

Color color = new Color(R,G,B);

g.setColor(color);

g.fillArc(x,y,W_H,W_H,0,360);

try {

Thread.sleep(500);

} catch (InterruptedException e) {

e.printStackTrace();

}

}

}

}