package com.company;

import javax.swing.*;
import java.awt.*;

class FrameTest {

    JFrame jFrame = new JFrame("登入");
    Container c = jFrame.getContentPane();
    JLabel a1 = new JLabel("使用者名稱:");
    JTextField username = new JTextField();
    JLabel a2 = new JLabel("密碼:");
    JPasswordField password 
 
= new JPasswordField();
    JButton okbtn = new JButton("確定");
    JButton cancelbtn = new JButton("取消");

    public FrameTest() {
        //設定窗體的位置及大小
        jFrame.setBounds(600, 200, 300, 220);
        //設定一層相當於桌布的東西
        c.setLayout(new BorderLayout());//佈局管理器
        //設定按下右上角X號後關閉
        jFrame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        
 
//初始化--往窗體裡放其他控制元件
        init();
        //設定窗體可見
        jFrame.setVisible(true);
    }

    public void init() {
        /*標題部分--North*/
        JPanel titlePanel = new JPanel();
        titlePanel.setLayout(new FlowLayout());
        titlePanel.add(new JLabel("XXX登入系統"));
        c.add(titlePanel, "North");

        
 
/*輸入部分--Center*/
        JPanel fieldPanel = new JPanel();
        fieldPanel.setLayout(null);
        a1.setBounds(50, 20, 50, 20);
        a2.setBounds(50, 60, 50, 20);
        fieldPanel.add(a1);
        fieldPanel.add(a2);
        username.setBounds(110, 20, 120, 20);
        password.setBounds(110, 60, 120, 20);
        fieldPanel.add(username);
        fieldPanel.add(password);
        c.add(fieldPanel, "Center");

        /*按鈕部分--South*/
        JPanel buttonPanel = new JPanel();
        buttonPanel.setLayout(new FlowLayout());
        buttonPanel.add(okbtn);
        buttonPanel.add(cancelbtn);
        c.add(buttonPanel, "South");
    }

    public static class Main {

        public static void main(String[] args) {
            new FrameTest();
        }
    }
}

效果