javaGUI实现简单的window关闭功能,该如何解决

javaGUI实现简单的window关闭功能
Java code
import java.awt.*;
import java.awt.event.*;

public class TestWindowClose {
    public static void main (String[] args) {
    }
}

class MyFrame extends Frame{
    MyFrame(String s){
        super(s);
        setLayout(null);
        setBounds(300,300,400,300);
        this.setBackground(new Color(204,204,255));
        setVisible(true);
    
        this.addWindowListener(
            new WindowAdapter(){
                public void windowClosing(WindowEvent e){
                    setVisible(false);
                    System.exit(-1);
                }
            }
                );
    }
}

为什么运行没有界面,好像窗口直接就关闭了

------解决方案--------------------
main方法为空...
------解决方案--------------------
MyFrame构造函数里面写
setDefaultCloseOperation(this.EXIT_ON_CLOSE);
就可以在窗口关闭的时候关掉进程了吧
------解决方案--------------------
探讨
main方法为空...

------解决方案--------------------
Java code

import java.awt.*;
import java.awt.event.*;

public class TestWindowClose {
    public static void main (String[] args) {
        String s = null;
        MyFrame myFrame=new MyFrame(s);
    }
}

class MyFrame extends Frame{
    MyFrame(String s){
        super(s);
        setLayout(null);
        setBounds(300,300,400,300);
        this.setBackground(new Color(204,204,255));
        setVisible(true);
    
        this.addWindowListener(
            new WindowAdapter(){
                public void windowClosing(WindowEvent e){
                    setVisible(false);
                    System.exit(-1);
                }
            }
                );
    }
}