NULL空布局

package com.swing.layerout;

import java.awt.BorderLayout;
import java.awt.FlowLayout;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.event.MouseEvent;
import java.awt.event.MouseListener;
import java.awt.event.WindowEvent;
import java.awt.event.WindowFocusListener;

import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JOptionPane;
import javax.swing.JPasswordField;
import javax.swing.JTextField;

public class Null2Test extends JFrame{
    
    JLabel lbluname = new JLabel("登录名:");
    JLabel lblupwd = new JLabel("密   码:");
    JTextField  jtf1 = new JTextField();
    JPasswordField  jtf2 = new JPasswordField();
    JButton jbok = new JButton("登  录");
    JLabel lblreg = new JLabel("注册点这里");
    public Null2Test(){
        
        init();
    }
    
    public void init(){
        
        this.setSize(400,300);
        this.setTitle("第一个JFrame窗体");
        //this.setIconImage(image);
        this.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);//这里是简单的处理了用户点击关闭的事件，
                                                            //如果想复杂的处理话就要使用事件处理机制
        
        this.setLayout(null);//没有布局
        
        
        jbok.addActionListener(new ActionListener() {
            
            @Override
            public void actionPerformed(ActionEvent arg0) {
                // TODO Auto-generated method stub
                
                //得到登录名
                String uname = jtf1.getText();
                //得到密码
                String upwd = new String(jtf2.getPassword());
                
                //调用DAO类的查询
                if("admin".equals(uname) && "123".equals(upwd)){
                    
                    JOptionPane.showMessageDialog(null, "用户名密码正确", "恭喜", JOptionPane.INFORMATION_MESSAGE );
                }else{
                    JOptionPane.showMessageDialog(null, "用户名或密码不正确", "失败", JOptionPane.ERROR_MESSAGE);
                    
                }
            }
        });
        
        JButton jbcan = new JButton("退  出");
        jbcan.addActionListener(new ActionListener() {
            
            @Override
            public void actionPerformed(ActionEvent arg0) {
                // TODO Auto-generated method stub
                System.exit(0);
            }
        });
        
        
        jtf2.setEchoChar('8');
        
        lbluname.setBounds(100, 70, 50, 20);
        lblupwd.setBounds(100, 110, 50, 20);
        
        jtf1.setBounds(170,70,90,20);
        jtf2.setBounds(170,110,90,20);
        
        jbok.setBounds(100, 170, 70, 20);
        jbcan.setBounds(230, 170, 70, 20);
        lblreg.setBounds(165, 210, 90, 23);
        lblreg.addMouseListener(new MouseListener() {
            
            @Override
            public void mouseReleased(MouseEvent arg0) {
                // TODO Auto-generated method stub
                
            }
            
            @Override
            public void mousePressed(MouseEvent arg0) {
                // TODO Auto-generated method stub
                
            }
            
            @Override
            public void mouseExited(MouseEvent arg0) {
                // TODO Auto-generated method stub
                
            }
            
            @Override
            public void mouseEntered(MouseEvent arg0) {
                // TODO Auto-generated method stub
                
            }
            
            @Override
            public void mouseClicked(MouseEvent arg0) {
                // TODO Auto-generated method stub

                JOptionPane.showMessageDialog(null, "要注册", "恭喜", JOptionPane.INFORMATION_MESSAGE );
            }
        });
        
        
        
        
        this.add(lbluname);
        this.add(lblupwd);
        this.add(jtf1);
        this.add(jtf2);
        this.add(jbok);
        this.add(jbcan);
        this.add(lblreg);
        this.setResizable(false);//不能改变窗体大小
        this.setVisible(true);
        
        
    }
    
    
    public static void main(String[] args) {
        
        new Null2Test();
    }
    

}