class Test extends JFrame {
    public Test() {
        this.addWindowListener(new WindowListener() {

            @Override
            public void windowActivated(WindowEvent arg0) {
                // TODO Auto-generated method stub
                
            }

            @Override
            public void windowClosed(WindowEvent arg0) {
                // TODO Auto-generated method stub
                
            }

            @Override
            public void windowClosing(WindowEvent arg0) {
                // TODO Auto-generated method stub
                
            }

            @Override
            public void windowDeactivated(WindowEvent arg0) {
                // TODO Auto-generated method stub
                
            }

            @Override
            public void windowDeiconified(WindowEvent arg0) {
                // TODO Auto-generated method stub
                
            }

            @Override
            public void windowIconified(WindowEvent arg0) {
                // TODO Auto-generated method stub
                
            }

            @Override
            public void windowOpened(WindowEvent arg0) {
                // TODO Auto-generated method stub
                
            }
            
        });
    }
}

------解决方案--------------------
探讨


可以。

调用 setUndecorated(true); 去掉自带的。
在右上角放置三个 JButton。

分别在点击时调用
setExtendedState(JFrame.ICONIFIED); // 最小
setExtendedState(JFrame.MAXIMIZED_BOTH); // 最大
dispose() or System.exit(0); //退出


------解决方案--------------------
package view;

import javax.swing.JButton;
import javax.swing.JLabel;
import javax.swing.JOptionPane;
import javax.swing.JPasswordField;
import javax.swing.JTextField;
import javax.swing.SwingUtilities;
import javax.swing.WindowConstants;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;

import bean.User;
import db.UserDAO;


public class Login extends javax.swing.JFrame implements ActionListener{
	 
	private static final long serialVersionUID = 1L;
		private JLabel jLabel1; 
	    private JLabel jLabel2; 
	    private JPasswordField txtpassword;  
	    private JButton btnCanel; 
	    private JButton btnOK; 
	    private JTextField txtuser;  
	 
	    public Login() { 
	        super(); 
	        initGUI(); 
	    } 
	//初始化界面  
	    private void initGUI() { 
	        try { 
	            setDefaultCloseOperation(WindowConstants.DISPOSE_ON_CLOSE); 
	            getContentPane().setLayout(null); 
	            { 
	                jLabel1 = new JLabel(); 
	                getContentPane().add(jLabel1); 
	                jLabel1.setText("\u7528\u6237\u540d:"); 
	                jLabel1.setBounds(79, 106, 42, 15); 
	            } 
	            { 
	                jLabel2 = new JLabel(); 
	                getContentPane().add(jLabel2); 
	                jLabel2.setText("\u5bc6  \u7801:"); 
	                jLabel2.setBounds(79, 140, 42, 15); 
	            } 
	            { 
	            	txtuser = new JTextField();