Java swing 实现登陆窗口

import javax.swing.*;
import java.awt.*;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;

public class Login {
    public static void main(String args[]) {
        Login l=new Login();
        l.showUI();
    }
    public void showUI() {
        javax.swing.JFrame jf = new javax.swing.JFrame();
        jf.setTitle("登录界面");
        jf.setSize(500, 190);
        jf.setDefaultCloseOperation(3);//直接关闭应用程序，System.exit(0)
        jf.setLocationRelativeTo(null);//窗口居中
        jf.setResizable(false);//窗体大小不可变
        java.awt.FlowLayout fl = new java.awt.FlowLayout(FlowLayout.LEFT, 30, 10);
        jf.setLayout(fl);
        java.awt.Dimension dim1 = new java.awt.Dimension(200, 30);//标签的大小
        java.awt.Dimension dim2 = new java.awt.Dimension(180, 30);//输入框的大小
        java.awt.Dimension dim3 = new java.awt.Dimension(100, 30);//按钮的大小
        //添加组件
        //登录名标签
        JLabel labname = new JLabel();
        labname.setText("登录名:");
        labname.setPreferredSize(dim1);
        jf.add(labname);
        //密码标签
        JLabel labpassword = new JLabel();
        labpassword.setText("密码:");
        labpassword.setPreferredSize(dim1);
        jf.add(labpassword);
        //登陆名输入框，监控事件
        JTextField textname = new JTextField();
        textname.setPreferredSize(dim2);
        jf.add(textname);

        //密码输入框，监控事件
        JPasswordField jp = new JPasswordField();
        jp.setPreferredSize(dim2);
        jf.add(jp);

        //添加button按钮
        javax.swing.JButton button1 = new javax.swing.JButton();
        button1.setText("登录");
        button1.setPreferredSize(dim3);
        jf.add(button1);

        javax.swing.JButton button2 = new javax.swing.JButton();
        button2.setText("取消");
        button2.setPreferredSize(dim3);
        jf.add(button2);

        jf.setVisible(true);

        LoginListener ll = new LoginListener(jf, textname, jp);
        button1.addActionListener(ll);

        CancelListener cancel =new CancelListener();
        button2.addActionListener(cancel);


    }

    public class CancelListener implements ActionListener{

        @Override
        public void actionPerformed(ActionEvent e) {
            System.exit(0);
        }
    }
    public class LoginListener implements ActionListener {
        private javax.swing.JTextField jt;//账号输入框对象
        private javax.swing.JPasswordField jp;//密码输入框对象
        private javax.swing.JFrame login;//定义一个窗体对象

        public LoginListener(javax.swing.JFrame login,javax.swing.JTextField jt,javax.swing.JPasswordField jp) {
            this.login=login;//获取登录界面
            this.jt=jt;//获取登录界面中的账号输入框对象
            this.jp=jp;//获取登录界面中的密码输入框对象
        }
        public void actionPerformed(ActionEvent e) {
            if(jt.getText().equals("Mike")&&jp.getText().equals("123")) {
                JOptionPane.showMessageDialog(null,"登陆成功","成功",1);
            }
            else if(!(jt.getText().equals("1")&&jp.getText().equals("1")) ){
                JOptionPane.showMessageDialog(null,"登录名或密码错误","失败",0);
            }

        }
    }


}