java中做一个按钮，点击按钮后画一个矩形的代码怎么写？

兄弟帮你写了一个：

import java.awt.Button;
import java.awt.Color;
import java.awt.Frame;
import java.awt.Graphics;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.event.WindowAdapter;
import java.awt.event.WindowEvent;
import java.util.Random;

public class Print {
public static void main(String[] args) {
new Te();
}
}

class Te extends Frame implements ActionListener {

Color cc = Color.red;
int x = -20, y = -50;
Random r = new Random();

public Te() {

this.setLayout(null);
Button b = new Button("画圆");
this.add(b);
b.setBounds(30,30,50,50);
b.addActionListener(this);
this.addWindowListener(new WindowAdapter () {

@Override
public void windowClosing(WindowEvent e) {
System.exit(0);
}

});
this.setBounds(200