java图书管理系统登录界面和验证

java图书管理系统登录界面和验证

1 首先将 “密码.txt”

java图书管理系统登录界面和验证

放在F盘根目录下，内容为：

java图书管理系统登录界面和验证

然后将图标放在 工作文件夹下面（当然也可以指定路径）

java图书管理系统登录界面和验证

2 建立两个类：

一 框架

import java.awt.BorderLayout;

import java.awt.Dimension;

import java.awt.GridLayout;

import java.awt.Image;

import java.awt.Toolkit;

import java.awt.event.ActionEvent;

import java.awt.event.ActionListener;

import java.io.BufferedReader;

import java.io.File;

import java.io.FileNotFoundException;

import java.io.FileReader;

import java.io.IOException;

import javax.swing.JButton;

import javax.swing.JFrame;

import javax.swing.JLabel;

import javax.swing.JTextField;

import javax.swing.JPasswordField;

import javax.swing.JPanel;

import javax.swing.SwingConstants;

public class LibraryloginFrame extends JFrame{

public LibraryloginFrame()

{

setTitle("图书管理系统-登陆"); //设置标题

setSize(DEFAULT_WIDTH,DEFAULT_HEIGHT);//设置大小

Toolkit kit = Toolkit.getDefaultToolkit();

Dimension  screenSize =kit.getScreenSize();

double WIDTH=screenSize.getWidth();

double HEIGHT =screenSize.getHeight();

this.setBounds((int)WIDTH/2,(int)HEIGHT/2,DEFAULT_WIDTH,DEFAULT_HEIGHT);

Image ima = kit.getImage("Office2010.jpg");//设置图标

setIconImage(ima);

//设置观感

String plaf = "com.sun.java.swing.plaf.nimbus.NimbusLookAndFeel";

try {

UIManager.setLookAndFeel(plaf);

} catch (ClassNotFoundException e2) {

// TODO Auto-generated catch block

e2.printStackTrace();

} catch (InstantiationException e2) {

// TODO Auto-generated catch block

e2.printStackTrace();

} catch (IllegalAccessException e2) {

// TODO Auto-generated catch block

e2.printStackTrace();

} catch (UnsupportedLookAndFeelException e2) {

e2.printStackTrace();

}

SwingUtilities.updateComponentTreeUI(this);

File file = new File("F:\\密码.txt");//打开保存的密码

try {

FileReader reader = new FileReader(file);

BufferedReader bf = new BufferedReader(reader);

reader.close();

bf.close();

try {

password2 = bf.readLine();

} catch (IOException e1) {

// TODO Auto-generated catch block

e1.printStackTrace();

}

} catch (FileNotFoundException e1) {

// TODO Auto-generated catch block

e1.printStackTrace();

}

final JTextField textField = new JTextField();

final JPasswordField passwordField = new JPasswordField();

passwordField.setEchoChar('*');

JPanel northPanel = new JPanel();

northPanel.setLayout(new GridLayout(2,2));

JLabel left1 = new JLabel("User name:",SwingConstants.CENTER);

JLabel left2 = new JLabel("Password:",SwingConstants.CENTER);

northPanel.add(left1);

northPanel.add(textField);

northPanel.add(left2);

northPanel.add(passwordField);

BorderLayout bl = new BorderLayout();

this.setLayout(bl);

add(northPanel,BorderLayout.NORTH);

field = new JTextField(30);

this.add(field,BorderLayout.CENTER);

JPanel southPanel = new JPanel();

add(southPanel,BorderLayout.SOUTH);

JButton button = new JButton("确定");

southPanel.add(button);

button.addActionListener(new ActionListener(){

public void actionPerformed(ActionEvent e)

{

text= textField.getText().trim();

password1 = new String(passwordField.getPassword());

result =text+password1;

if(result.equals(password2))//验证用户名和密码

{

field.setText("恭喜你，登陆成功!!")  ;  

}else {

field.setText("对不起，账号或密码错误，请重新输入!!")  ;

textField.setText("");

passwordField.setText("");

}

}});

}

private static final int DEFAULT_WIDTH = 300;

private static final int DEFAULT_HEIGHT =200;

private JTextField field;//显示登陆结果

private String text;//放用户名

private String password1;//放登陆密码

private String result;//放用户名+密码

private String password2;//放从密码文件里读取的密码

}

二 运行类

import java.awt.EventQueue;

import javax.swing.JFrame;

public class LibraryloginText {

public static void main(String[] args) 

{

// TODO Auto-generated method stub

EventQueue.invokeLater(new Runnable(){

public void run()

{

LibraryloginFrame frame = new LibraryloginFrame();

frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

frame.setVisible(true);

}

});

}

}

效果：

一

java图书管理系统登录界面和验证

二

java图书管理系统登录界面和验证

三

java图书管理系统登录界面和验证