Java程序右上角红叉的响应,该怎么处理

Java程序右上角红叉的响应
我用SWING做的程序，希望用户单击右上角红叉的时候执行一段代码……这个应该怎么做？

[解决办法]
使用WindowsListener进行窗口关闭事件的监听，给你贴一个实例

Java code

import javax.swing.*;import java.awt.event.WindowAdapter;import java.awt.event.WindowEvent;/** * Created by IntelliJ IDEA. * User: admin * Date: 2011-9-26 * Time: 16:11:50 * To change this template use File | Settings | File Templates. */public class Demo1 extends JFrame {     private JButton btn=new JButton("click");    public Demo1(String title){        super(title);        this.add(btn);        this.pack();        this.setVisible(true);        this.addWindowListener(new WindowAdapter(){            @Override            public void windowClosing(WindowEvent e) {//                super.windowClosing(e);    //To change body of overridden methods use File | Settings | File Templates.               //这里写你想实现的代码，我只写了一行println                System.out.println("windowClosing");                System.exit(0);            }        });    }    public static void main(String[] args){            new Demo1("demo");    }}