通过调用实例化一个JFrame框架，在框架内嵌入JPanel，在JPanel上进行添加控件。

package com.main.frame;

import java.awt.*;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.event.FocusEvent;
import java.awt.event.FocusListener;

import javax.swing.*;

public class Login {
	public static void main(String[] args) {
		JFrame f1 = new JFrame();
		f1.setTitle("欢迎登陆");
		f1.setBounds(400, 200, 400, 270);
		f1.setResizable(false);
		f1.invalidate(); // 保证组件是有效的布局
		f1.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
		// 实例化各组件
		Container con = f1.getContentPane(); //生成一个容器
		con.setLayout(new GridLayout(7,1));  //设置容器布局
		JLabel welcome = new JLabel("欢迎登陆本系统");
		JLabel usname = new JLabel();
		JLabel paswd = new JLabel();
		JTextField text1 = new JTextField(12);
		JPasswordField text2 = new JPasswordField(12);
		JButton login = new JButton("登陆");
		JButton regist = new JButton("注册");
		JPanel p1 = new JPanel();
		JPanel p2 = new JPanel();
		JPanel p3 = new JPanel();
		JPanel p4 = new JPanel();
		//调用FocusListener方法，获取鼠标焦点，实现提示功能。
		text1.addFocusListener(new Tip(text1,"请输入账号：")); 
		text2.addFocusListener(new Tip(text2, "请输入密码："));
		welcome.setFont(new Font("宋体", Font.BOLD, 20));
		p1.add(welcome);
		con.add(p1); 
		usname.setText("账号：");
		paswd.setText("密码：");
		p2.add(usname);
		p2.add(text1);	
		con.add(p2); 
		p3.add(paswd);
		p3.add(text2);
		con.add(p3);
		p4.add(login);
		login.addActionListener(new LoginAc());
		p4.add(regist);
		con.add(p4);
		f1.setVisible(true);
	}
	
}

package com.main.frame;

import java.awt.event.FocusEvent;
import java.awt.event.FocusListener;

import javax.swing.JTextField;

public  class Tip implements FocusListener{
	private String hindentext;
	private JTextField textField;
	public Tip(JTextField jtextfield,String hindentext) {
		this.hindentext = hindentext;
		this.textField = jtextfield;
		jtextfield.setText(hindentext);
	}
	

	@Override
	public void focusGained(FocusEvent e) {
		// TODO Auto-generated method stub
		String temp = textField.getText();
		if(temp.equals(hindentext)) {
			textField.setText("");
		}
	}

	@Override
	public void focusLost(FocusEvent e) {
		// TODO Auto-generated method stub
		String temp = textField.getText();
		if(temp.equals("")) {
			textField.setText(hindentext);
		}
	}
}