图书管理系统代码  1 Libraryload …

// 新增了 焦点监听器 当用户名文本域失去焦点 时 进行提示！！！！

import java.awt.BorderLayout;

import java.awt.Color;

import java.awt.FlowLayout;

import java.awt.GridBagLayout;

import java.awt.event.ActionEvent;

import java.awt.event.ActionListener;

import java.awt.event.FocusEvent;

import java.awt.event.FocusListener;

import java.io.BufferedReader;

import java.io.File;

import java.io.FileNotFoundException;

import java.io.FileReader;

import java.io.IOException;

import javax.swing.ImageIcon;

import javax.swing.JButton;

import javax.swing.JFrame;

import javax.swing.JLabel;

import javax.swing.JOptionPane;

import javax.swing.JPanel;

import javax.swing.JPasswordField;

import javax.swing.JTextField;

import javax.swing.SwingConstants;

public class Libraryload extends InitFrame

{

public Libraryload(){

super("图书管理系统—登录","Library.png",360,200);

this.setDefaultCloseOperation (JFrame.DISPOSE_ON_CLOSE);

//设置布局管理器

this.setLayout(new BorderLayout());

// 创建面板

centerPanel = new JPanel();

southPanel = new JPanel();

// 将面板添加到窗体

this.add(centerPanel,BorderLayout.CENTER);

this.add(southPanel,BorderLayout.SOUTH);

// 设置面板布局

centerPanel.setLayout(new GridBagLayout());

southPanel.setLayout(new FlowLayout());

// 实例化焦点监听器

addUserFocusListener ufl = new addUserFocusListener();

// 初始化标签

label_user= new JLabel("请输入用户名:");

label_result_f = new JLabel("该用户名正确!!!",new ImageIcon("label_result_t.png"),SwingConstants.RIGHT);

label_result_f.setForeground(Color.red);//设置标签前景色

//   添加焦点事件 当失去焦点时   如果不可用给予提示

label_result_f.setVisible(false);

label_result_t = new JLabel("该用户名不存在!!",new ImageIcon("label_result_f.png"),SwingConstants.RIGHT);

label_result_t.setForeground(Color.red);//设置标签前景色

//   添加焦点事件 当失去焦点时   如果不可用给予提示

label_result_t.setVisible(false);

label_password = new JLabel("请输入密码:");

// 初始化文本域

field_user = new JTextField(20);

field_user.addFocusListener(ufl);

field_password=new JPasswordField(20);

field_password.addFocusListener(ufl);

// 添加中间面板元素

centerPanel.add(label_user,new GBC(0,1).setInsets(1));

centerPanel.add(label_password,new GBC(0,2).setInsets(1));

centerPanel.add(label_result_f,new GBC(1,1).setInsets(1));

centerPanel.add(label_result_t,new GBC(1,1).setInsets(1));

centerPanel.add(field_user,new GBC(1,1).setInsets(1));

centerPanel.add(field_password,new GBC(1,2).setInsets(1));

//   设置下部边框

JButton button_ok = new JButton("确定",new ImageIcon("ok.png"));

button_ok.addActionListener(new ActionListener(){

public void actionPerformed(ActionEvent e)

{

boolean has=false;

String getpassW =new String(field_password.getPassword());//获取密码

String getUser = new String(field_user.getText());

if(getpassW.equals("")||getUser.equals(""))

{

JLabel label_result = new JLabel("用户名和密码不可为空，请重新输入！！");

JOptionPane.showConfirmDialog(Libraryload.this, label_result,"图书管理系统-登录", JOptionPane.WARNING_MESSAGE,JOptionPane.OK_OPTION , new ImageIcon("result.png"));

}else {

File file_org= new File("E:\\图书管理系统\\password.dat");

FileReader fr;

try {

fr = new FileReader(file_org);

BufferedReader br = new BufferedReader(fr);

do{

password_org2 = br.readLine();

if(password_org2!=null)

{

password_input = field_user.getText()+","+new String(field_password.getPassword());

if(password_org2.equals(password_input))

{

has=true;  

}

}

}while(password_org2!=null);

fr.close();

br.close();

} catch (FileNotFoundException e3) 

{

e3.printStackTrace();

}catch(IOException e1)

{

e1.printStackTrace();

}

if(has==true){

try {

Thread.sleep(2000);

} catch (InterruptedException e1) {

e1.printStackTrace();

}

try {

Thread.sleep(1000);

} catch (InterruptedException e1)

{

e1.printStackTrace();

}

Libraryload.this.setVisible(false);

Libraryload.this.dispose();

LibraryMainF lm = new LibraryMainF();

lm.setVisible(true);

}else

{

JLabel label_result = new JLabel("用户名或密码错误，请重新输入！！");

JOptionPane.showConfirmDialog(Libraryload.this, label_result,"图书管理系统-登录", JOptionPane.WARNING_MESSAGE,JOptionPane.OK_OPTION , new ImageIcon("result.png"));

}

}

}

});

JButton   button_cancel = new JButton("重置",new ImageIcon("cancel.png"));

button_cancel.addActionListener(new ActionListener()

{

public void actionPerformed(ActionEvent e)

{

field_user.setText("");

field_password.setText("");

}

}   );

southPanel.add(button_ok);

southPanel.add(button_cancel);

}

//此焦点类的目的是判断当用户输完用户名时 是否与已有用户相同 并给予提示！

private class addUserFocusListener implements FocusListener

{

// 当用户名区获取焦点 则将给出的提示取消

public void focusGained(FocusEvent fe) 

{

if(fe.getSource().equals(field_user))

{

if(label_result_f.isVisible()==true)

{

label_result_f.setVisible(false);

}else if(label_result_t.isVisible()==true)

{

label_result_t.setVisible(false);

}

// 由于has （重复）是全局变量，如果没有下面那句当第一次输入时重复的用户名时 ，如果可用再次使用将

// 不再提示可用的标签！！

xianshi=false;

}

}

public void focusLost(FocusEvent fe) 

{

if(fe.getSource().equals(field_user))

{

System.out.println("7");

// 读取原始密码

file_pass_org = new File("E:\\图书管理系统\\password.dat");

FileReader fr;

try {

fr = new FileReader(file_pass_org);

BufferedReader br = new BufferedReader(fr);

do{

password_org1= br.readLine();

if(password_org1!=null){

int index =password_org1.indexOf(',');//字符串中第一次出现逗号的索引

String get_user_name =password_org1.substring(0,index);//逗号前的内容即用户名

String get_input_user = field_user.getText();//获取新的用户名

if(get_user_name.equals(get_input_user))

{

label_result_f.setVisible(true);

xianshi=true;

}

}

}while(password_org1!=null);

fr.close();

br.close();

if(!xianshi)

{

label_result_t.setVisible(true);

}

} catch (FileNotFoundException e1) 

{

e1.printStackTrace();

}catch(IOException e2)

{

e2.printStackTrace();

}

}

}

}

private JPanel centerPanel;

private JPanel southPanel;

private   JLabel label_user;

private JLabel label_password ;

private JLabel label_result_t;

private JLabel   label_result_f;

private JTextField field_user;

private JPasswordField field_password;

private String password_input;

private String password_org1;

private String password_org2;

private File file_pass_org;

private boolean xianshi=false;

}