package com.shiyanlou.entity;public class User { private String ID; private String name; private String passwd; public String getName() { return name; } public void setID(String iD) { ID = iD; } public String getID() { return ID; } public void setName(String name) { this.name = name; } public String getPasswd() { return passwd; } public void setPasswd(String passwd) { this.passwd = passwd; }}package com.shiyanlou.util;import java.io.BufferedReader;import java.io.BufferedWriter;import java.io.File;import java.io.FileReader;import java.io.FileWriter;import java.io.IOException;import javax.swing.text.Document;public class Diary { public static void addDiary(String pathname, String title, String txt) { File dirfile = new File(pathname); BufferedWriter bufw = null; dirfile.mkdirs(); File file = new File(dirfile, title + ".ky"); try { bufw = new BufferedWriter(new FileWriter(file, true)); bufw.write(txt); } catch (IOException e) { // TODO Auto-generated catch block e.printStackTrace(); } finally { if (bufw != null) { try { bufw.close(); } catch (IOException e) { // TODO Auto-generated catch block e.printStackTrace(); } } } } public static void read(File file, Document doc) { try (BufferedReader bufr = new BufferedReader(new FileReader(file));) { String txt = null; String line = System.getProperty("line.separator"); while ((txt = bufr.readLine()) != null) { doc.insertString(doc.getLength(), txt + line, null); } } catch (Exception e1) { // TODO Auto-generated catch block e1.printStackTrace(); } }}package com.shiyanlou.util;import java.io.File;import java.io.FileOutputStream;import java.io.IOException;import java.util.ArrayList;import java.util.Iterator;import java.util.List;import java.util.Map;import java.util.TreeMap;import org.jdom2.Attribute;import org.jdom2.Document;import org.jdom2.Element;import org.jdom2.JDOMException;import org.jdom2.input.SAXBuilder;import org.jdom2.output.XMLOutputter;public class JDOM { public static String write(String n, String p, String id) { // TODO Auto-generated method stub String path = "/home/shiyanlou/Desktop/UserInfo.xml"; File file = new File(path); SAXBuilder saxBuilder = new SAXBuilder(); Document doc; try { doc = saxBuilder.build(file); Element root = doc.getRootElement(); //\u5F97\u5230\u6839\u5143\u7D20 Element user = new Element("User"); //\u5EFA\u7ACBUser\u5143\u7D20 Element name = new Element("name");//\u5EFA\u7ACBname\u5143\u7D20 Element passwd = new Element("passwd");//\u5EFA\u7ACBpasswd\u5143\u7D20 if (checkID(id, root)) { user.setAttribute(new Attribute("id", id)); name.setText(n); passwd.setText(p); user.addContent(name); user.addContent(passwd); root.addContent(user); XMLOutputter out = new XMLOutputter(); out.output(doc, new FileOutputStream(file)); return "Successful registration";//\u8FD4\u56DE\u6CE8\u518C\u6210\u529F } else return "ID already exists, please input again"; } catch (JDOMException e) { // TODO Auto-generated catch block e.printStackTrace(); } catch (IOException e) { // TODO Auto-generated catch block e.printStackTrace(); } return "ERROR"; } public static boolean checkID(String id, Element root) { boolean flag = true; @SuppressWarnings("unchecked") List<Element> list = root.getChildren("User"); Iterator<Element> it = list.iterator(); while (it.hasNext()) { Element e = (Element) it.next(); if (e.getAttributeValue("id").equals(id)) { flag = false; } } return flag; } public static String read(String id, String passwd) { String path = "/home/shiyanlou/Desktop/UserInfo.xml"; File file = new File(path); SAXBuilder saxBuilder = new SAXBuilder(); try { Document doc = saxBuilder.build(file); Element root = doc.getRootElement(); String info = getPasswd(root).get(id); if (info == null) { return "User does not exist!!"; } String[] buf = info.split("/"); if (buf[0].equals(passwd)) { return "Successful landing/" + buf[1]; } } catch (JDOMException e) { // TODO Auto-generated catch block e.printStackTrace(); } catch (IOException e) { // TODO Auto-generated catch block e.printStackTrace(); } return "Wrong password!!"; } @SuppressWarnings("unchecked")private static Map<String, String> getPasswd(Element root) { Map<String, String> map = new TreeMap<String, String>();//\u5B58\u8D2E\u7528\u6237\u4FE1\u606F List<Element> list = new ArrayList<Element>(); list = root.getChildren("User"); Iterator<Element> it = list.iterator(); while (it.hasNext()) { Element e = it.next(); String id = e.getAttributeValue("id"); String passwd = e.getChildText("passwd"); String name = e.getChildText("name"); map.put(id, getInfo(passwd, id)); } return map; } private static String getInfo(String passwd, String name) { return passwd + "/" + name; }}package com.shiyanlou.util;import com.shiyanlou.entity.User;public class Register { static User user = new User(); public static String checkName(String name) { user.setName(name); return null; } public static String checkID(String ID) { if (ID.matches("\\d{1,8}")) { user.setID(ID); return null; } else return "ID not conform to the rules"; } public static String checkPasswd(String passwd) { if (passwd.matches("\\d{6,15}")) { user.setPasswd(passwd); return null; } else return "Password not conform to the rules"; } public static String register(String name,String passwd,String ID) { user.setName(name); user.setPasswd(passwd); user.setID(ID); return (JDOM.write(user.getName(), user.getPasswd(), user.getID())); }}package com.shiyanlou.view;import java.awt.EventQueue;import java.awt.Font;import java.awt.event.KeyAdapter;import java.awt.event.KeyEvent;import java.awt.event.MouseAdapter;import java.awt.event.MouseEvent;import javax.swing.JButton;import javax.swing.JFrame;import javax.swing.JLabel;import javax.swing.JPanel;import javax.swing.border.EmptyBorder;public class IndexGUI extends JFrame { private JPanel contentPane; private static IndexGUI frame; public static void main(String[] args) { init(); } public static void init() { EventQueue.invokeLater(new Runnable() { public void run() { try { frame = new IndexGUI(); frame.setVisible(true); } catch (Exception e) { e.printStackTrace(); } } }); } public IndexGUI() { setTitle("KnowYou"); setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); setBounds(100, 100, 650, 400); contentPane = new JPanel(); contentPane.setBorder(new EmptyBorder(5, 5, 5, 5)); setContentPane(contentPane); contentPane.setLayout(null); JLabel lblNewLabel = new JLabel("Welcome to use KnowYou"); lblNewLabel.setBounds(132, 74, 386, 35); lblNewLabel.setFont(new Font("Ubuntu", Font.BOLD | Font.ITALIC, 30)); contentPane.add(lblNewLabel); JButton login = new JButton("Login"); login.addMouseListener(new MouseAdapter() { @Override public void mouseClicked(MouseEvent e) { event_Login(); } }); login.addKeyListener(new KeyAdapter() { @Override public void keyPressed(KeyEvent e) { if(e.getKeyCode()==KeyEvent.VK_ENTER) { event_Login(); } } }); login.setBounds(65, 263, 124, 45); contentPane.add(login); JButton register = new JButton("Sign Up"); register.addMouseListener(new MouseAdapter() { @Override public void mouseClicked(MouseEvent e) { event_register(); } }); register.addKeyListener(new KeyAdapter() { @Override public void keyPressed(KeyEvent e) { if(e.getKeyCode()==KeyEvent.VK_ENTER) { event_register(); } } }); register.setBounds(489, 263, 109, 45); contentPane.add(register); } private void event_Login() { setVisible(false); new LoginGUI().loginGUI(); } private void event_register() { setVisible(false); new RegisterGUI().registerGUI(); }}package com.shiyanlou.view;import java.awt.EventQueue;import java.awt.Font;import java.awt.event.KeyAdapter;import java.awt.event.KeyEvent;import java.awt.event.MouseAdapter;import java.awt.event.MouseEvent;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.border.EmptyBorder;import com.shiyanlou.util.JDOM;public class LoginGUI extends JFrame { private static final long serialVersionUID = 4994949944841194839L; private JPanel contentPane; private JTextField IDtxt; private JLabel Passwdlabel; private JPasswordField passwordField; private JButton login; private JButton back; /** * Launch the application. * @return */ public void loginGUI() { EventQueue.invokeLater(new Runnable() { public void run() { try { LoginGUI frame = new LoginGUI(); frame.setVisible(true); } catch (Exception e) { e.printStackTrace(); } } }); } /** * Create the frame. */ public LoginGUI() { setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); setBounds(100, 100, 650, 400); contentPane = new JPanel(); contentPane.setBorder(new EmptyBorder(5, 5, 5, 5)); setContentPane(contentPane); contentPane.setLayout(null); JLabel IDlabel = new JLabel("Please input ID"); IDlabel.setBounds(68, 170, 100, 39); contentPane.add(IDlabel); IDtxt = new JTextField(); IDtxt.setBounds(220, 179, 126, 21); contentPane.add(IDtxt); IDtxt.setColumns(10); Passwdlabel = new JLabel("Please input password"); Passwdlabel.setBounds(68, 219, 150, 50); contentPane.add(Passwdlabel); passwordField = new JPasswordField(); passwordField.setBounds(220, 234, 126, 21); contentPane.add(passwordField); login = new JButton("login"); login.addMouseListener(new MouseAdapter() { @Override public void mouseClicked(MouseEvent e) { event_login(); } }); login.addKeyListener(new KeyAdapter() { public void keyPressed(KeyEvent e) { if(e.getKeyCode()==KeyEvent.VK_ENTER) { event_login(); } } }); login.setBounds(239, 310, 93, 23); contentPane.add(login); back = new JButton("BACK"); back.addMouseListener(new MouseAdapter() { @Override public void mouseClicked(MouseEvent e) { IndexGUI.init(); setVisible(false); } }); back.setBounds(507, 310, 93, 23); contentPane.add(back); JLabel label = new JLabel("Welcome to use KnowYou"); label.setFont(new Font("Ubuntu", Font.BOLD | Font.ITALIC, 30)); label.setBounds(142, 54, 386, 35); contentPane.add(label); } private void event_login() { String id=IDtxt.getText(); String passwd=new String(passwordField.getPassword()); String flag=JDOM.read(id, passwd); if(flag.contains("Successful landing")) { String[] bufs=flag.split("/"); String name=bufs[1]; JOptionPane.showMessageDialog(contentPane, "Welcome: "+name,"Welcome",JOptionPane.PLAIN_MESSAGE); UsersGUI.init(name); setVisible(false); } else { JOptionPane.showMessageDialog(contentPane,flag,"ERROR",JOptionPane.ERROR_MESSAGE); } }}package com.shiyanlou.view;import java.awt.EventQueue;import java.awt.Font;import java.awt.event.ActionEvent;import java.awt.event.ActionListener;import java.awt.event.MouseAdapter;import java.awt.event.MouseEvent;import javax.swing.JButton;import javax.swing.JFrame;import javax.swing.JLabel;import javax.swing.JOptionPane;import javax.swing.JPanel;import javax.swing.JTextField;import javax.swing.border.EmptyBorder;import com.shiyanlou.util.Register;public class RegisterGUI extends JFrame { private static final long serialVersionUID = 3250371445038102261L; private JPanel contentPane; private JTextField nametext; private JTextField IDtext; private JTextField passwdtext; /** * Launch the application. */ public void registerGUI() { EventQueue.invokeLater(new Runnable() { public void run() { try { RegisterGUI frame = new RegisterGUI(); frame.setVisible(true); } catch (Exception e) { e.printStackTrace(); } } }); } /** * Create the frame. */ public RegisterGUI() { setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); setBounds(100, 100, 650, 400); contentPane = new JPanel(); contentPane.setBorder(new EmptyBorder(5, 5, 5, 5)); setContentPane(contentPane); contentPane.setLayout(null); JLabel namelabel = new JLabel("Please input user name"); namelabel.setBounds(102, 91, 151, 23); contentPane.add(namelabel); JLabel IDlabel = new JLabel("Please input user ID"); IDlabel.setBounds(102, 160, 151, 23); contentPane.add(IDlabel); JLabel passwdlaber = new JLabel("Please input user password"); passwdlaber.setBounds(102, 224, 163, 23); contentPane.add(passwdlaber); nametext = new JTextField(); nametext.setBounds(271, 92, 92, 21); contentPane.add(nametext); nametext.setColumns(10); IDtext = new JTextField(); IDtext.setBounds(271, 161, 92, 21); contentPane.add(IDtext); IDtext.setColumns(8); passwdtext = new JTextField(); passwdtext.setBounds(271, 225, 92, 21); contentPane.add(passwdtext); passwdtext.setColumns(10); JButton register = new JButton("Sign Up"); register.addMouseListener(new MouseAdapter() { public void mouseClicked(MouseEvent e) { register.addMouseListener(new MouseAdapter() { public void mouseClicked(MouseEvent e) { String name = nametext.getText(); String ID = IDtext.getText(); String passwd = passwdtext.getText(); if (Register.checkID(ID) == null) { if (Register.checkPasswd(passwd) == null) { String srt = Register.register(name, passwd, ID); JOptionPane.showMessageDialog(contentPane,srt,"information", JOptionPane.PLAIN_MESSAGE); setVisible(false); new IndexGUI().init(); } else { JOptionPane.showMessageDialog(contentPane,Register.checkPasswd(passwd), "ERROR", JOptionPane.ERROR_MESSAGE); } } else { JOptionPane.showMessageDialog(contentPane,Register.checkID(ID), "ERROR", JOptionPane.ERROR_MESSAGE); } } }); } }); register.setBounds(321, 305, 93, 23); contentPane.add(register); JButton back = new JButton("BACK"); //\u8FD4\u56DE\u6309\u94AE back.addMouseListener(new MouseAdapter() { @Override public void mouseClicked(MouseEvent e) { IndexGUI.init(); setVisible(false); } }); back.setBounds(531, 305, 93, 23); contentPane.add(back); JLabel label = new JLabel("Welcome to use KnowYou"); label.setFont(new Font("Ubuntu", Font.BOLD | Font.ITALIC, 30)); label.setBounds(143, 26, 374, 35); contentPane.add(label); JLabel lblNewLabel = new JLabel("(There are 1 to 8 numbers)"); lblNewLabel.setBounds(373, 164, 163, 15); contentPane.add(lblNewLabel); JLabel lblNewLabel_1 = new JLabel("(There are 6 to 15 numbers)"); lblNewLabel_1.setBounds(373, 228, 163, 15); contentPane.add(lblNewLabel_1); }}package com.shiyanlou.view;import java.awt.Color;import java.awt.EventQueue;import java.awt.Font;import java.awt.event.ActionEvent;import java.awt.event.ActionListener;import java.awt.event.MouseAdapter;import java.awt.event.MouseEvent;import java.io.File;import javax.swing.JButton;import javax.swing.JEditorPane;import javax.swing.JFileChooser;import javax.swing.JFrame;import javax.swing.JInternalFrame;import javax.swing.JLabel;import javax.swing.JOptionPane;import javax.swing.JPanel;import javax.swing.JTabbedPane;import javax.swing.JTextField;import javax.swing.JTextPane;import javax.swing.border.EmptyBorder;import javax.swing.filechooser.FileNameExtensionFilter;import com.shiyanlou.util.Diary;public class UsersGUI extends JFrame { private JPanel contentPane; private JTextField textField; private JFileChooser chooser; private static String pathname; public static void init(String path) { //\u521D\u59CB\u5316\u65B9\u6CD5 pathname = path; EventQueue.invokeLater(new Runnable() { public void run() { try { UsersGUI frame = new UsersGUI(); frame.setVisible(true); } catch (Exception e) { e.printStackTrace(); } } }); } /** * Create the frame. */ public UsersGUI() { setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); setBounds(100, 100, 600, 400); contentPane = new JPanel(); contentPane.setBorder(new EmptyBorder(5, 5, 5, 5)); setContentPane(contentPane); contentPane.setLayout(null); JTabbedPane tabbedPane = new JTabbedPane(JTabbedPane.TOP); tabbedPane.setToolTipText("KonwYou"); tabbedPane.setBounds(0, 0, 574, 67); contentPane.add(tabbedPane); final JPanel panel = new JPanel(); tabbedPane.addTab("Management Journal", null, panel, null); chooser = new JFileChooser(".\\"+pathname); FileNameExtensionFilter filter=new FileNameExtensionFilter("Allowed","ky"); chooser.setFileFilter(filter); JButton readButton = new JButton("Read the diary"); readButton.addMouseListener(new MouseAdapter() { @Override public void mouseClicked(MouseEvent e) { int value = chooser.showOpenDialog(panel); JInternalFrame internalFrame_Read = new JInternalFrame("Read the diary", false, true, false, false); internalFrame_Read.setBounds(0, 77, 584, 275); contentPane.add(internalFrame_Read); internalFrame_Read.getContentPane().setLayout(null); JTextPane txtDiary = new JTextPane(); txtDiary.setBounds(0, 0, 568, 246); internalFrame_Read.getContentPane().add(txtDiary); javax.swing.text.Document doc=txtDiary.getDocument(); txtDiary.setBackground(Color.GREEN); txtDiary.setEditable(false); if (value == JFileChooser.APPROVE_OPTION) { File file = chooser.getSelectedFile(); if(file.exists()) { Diary.read(file, doc); internalFrame_Read.setVisible(true); } } } }); panel.add(readButton); JButton addButton = new JButton("Create a diary");//\u65B0\u5EFA\u6309\u94AE addButton.addMouseListener(new MouseAdapter() { @Override public void mouseClicked(MouseEvent e) { final JInternalFrame internalFrame_Write = new JInternalFrame("Create a diary",false, true, false, false); internalFrame_Write.setBounds(0, 77, 584, 275); contentPane.add(internalFrame_Write); internalFrame_Write.getContentPane().setLayout(null); textField = new JTextField(); textField.setBounds(76, 0, 492, 21); internalFrame_Write.getContentPane().add(textField); textField.setColumns(10); JLabel label = new JLabel("Title"); label.setFont(new Font("\u6977\u4F53", Font.PLAIN, 12)); label.setBounds(46, 3, 52, 15); internalFrame_Write.getContentPane().add(label); final JEditorPane editorPane = new JEditorPane(); editorPane.setBounds(0, 31, 568, 179); internalFrame_Write.getContentPane().add(editorPane); JButton save = new JButton("SAVE"); save.setBounds(465, 213, 93, 23); save.addMouseListener(new MouseAdapter() { public void mouseClicked(MouseEvent e) { String title = textField.getText(); String txt = editorPane.getText(); Diary.addDiary(pathname, title, txt); internalFrame_Write.setVisible(false); } }); internalFrame_Write.getContentPane().add(save); internalFrame_Write.setVisible(true); } }); panel.add(addButton); JButton delButton = new JButton("Delete"); delButton.addActionListener(new ActionListener() { public void actionPerformed(ActionEvent e) { File file=null; int value=chooser.showOpenDialog(panel); if(value==JFileChooser.APPROVE_OPTION) { file=chooser.getSelectedFile(); int x=JOptionPane.showConfirmDialog(panel,"Confirm delete?","Please confirm",JOptionPane.OK_CANCEL_OPTION,JOptionPane.QUESTION_MESSAGE); if(file.exists()) { if(x==JOptionPane.OK_OPTION) { file.delete(); JOptionPane.showMessageDialog(panel, "Delete Success!","information", JOptionPane.PLAIN_MESSAGE); } } } } }); panel.add(delButton); JButton back = new JButton("BACK"); back.addActionListener(new ActionListener() { public void actionPerformed(ActionEvent e) { IndexGUI.init(); setVisible(false); } }); panel.add(back); }}需要对应着 User 类来设计一个 XML 文档，用于持久化存储用户信息。
在桌面空白处右键点击，选择从模版创建一个空文件。
文件名可以填写为 UserInfo.xml。
创建完成后可以在桌面上找到这个 UserInfo.xml 文件。
右键点击该文件，用 gedit 编辑器打开它。
在编辑器中输入 XML 文件的信息和项目中会用到的标签 Users。
<?xml version="1.0" encoding="UTF-8"?> <Users></Users>
编辑完成后，点击保存按钮保存该文件，然后关闭编辑器。 UserInfo.xml 如图：
以上就完成了我们保存用户信息的 xml 文档。
JDOM 是一种使用 XML（标准通用标记语言下的一个子集） 的独特 Java 工具包。它的设计包含 Java 语言的语法乃至语义。
要使用 JDOM 解析 XML 文件，需要下载 JDOM 的包，实验中使用的是 jdom-1.1。解压之后，将 lib 文件夹下的 *.jar 文件以及 build 文件夹下的 jdom.jar 拷贝到工程文件夹下，然后就可以使用 JDOM 操作 XML 文件了。
在实验环境中下载 jdom 可以使用下面的方式，打开 Xfce 终端，输入命令：
$ wget https://labfile.oss.aliyuncs.com/courses/480/jdom-2.0.6.zip $ unzip jdom-2.0.6.zip
首先需要将 JDOM 的 jar 包导入到我们的工程中。
右键点击项目目录，选择 Properties 进入项目属性设置。
在 Java Build Path 设置项里切换到 Libraries 选项卡，然后点击右侧的 Add External JARs... 按钮。
在弹出的 JAR Selection 对话框中选择 Shiyanlou 目录下刚解压的 JDOM 相关包 jdom-2.0.6.jar，然后点击 确定 按钮完成添加。
最后在属性页点击 OK 完成设置。
接下来就需要对 JDOM 类进行编辑。
在类 JDOM.java中，主要包含了两个方法，write() 和 read() 方法，分别用于将用户信息写入到 xml 文档中和读出用户信息。