java圖書管理系統登入界面和驗證

 建立兩個類：

一 架構

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("圖書管理系統-登陸"); //設定标題

setSize(DEFAULT_WIDTH,DEFAULT_HEIGHT);//設定大小

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");//設定圖示

setIconImage(ima);

//設定觀感

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) {

} catch (IllegalAccessException e2) {

} catch (UnsupportedLookAndFeelException e2) {

}

SwingUtilities.updateComponentTreeUI(this);

File file = new File("F:\\密碼.txt");//打開儲存的密碼

FileReader reader = new FileReader(file);

BufferedReader bf = new BufferedReader(reader);

reader.close();

bf.close();

password2 = bf.readLine();

} catch (IOException e1) {

e1.printStackTrace();

} catch (FileNotFoundException e1) {

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))//驗證使用者名和密碼

  field.setText("恭喜你，登陸成功!!")  ;    

  }else {

   field.setText("對不起，賬号或密碼錯誤，請重新輸入!!")  ;

   textField.setText("");

   passwordField.setText("");

   }

   }});

private static final int DEFAULT_WIDTH = 300;

private static final int DEFAULT_HEIGHT =200;

private JTextField field;//顯示登陸結果

private String text;//放使用者名

private String password1;//放登陸密碼

private String result;//放使用者名+密碼

private String password2;//放從密碼檔案裡讀取的密碼

二 運作類

import java.awt.EventQueue;

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);

});

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版權聲明：本文為CSDN部落客「明明如月學長」的原創文章，遵循CC 4.0 BY-SA版權協定，轉載請附上原文出處連結及本聲明。

原文連結：

https://blog.csdn.net/w605283073/article/details/46572389