【计理01组30号】Java 实现日记写作软件
项目分析
代码设计
com.shiyanlou.entity
User.java
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;
}
}com.shiyanlou.util
Diary.java
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();
}
}
}JDOM.java
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;
}
}Register.java
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()));
}
}com.shiyanlou.view
IndexGUl.java
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();
}
}LoginGUl.java
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);
}
}
}RegisterGUl.java
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);
}
}UsersGUl.java
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);
}
}要点解析
XML文档
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。
什么是 XML
- XML 指可扩展标记语言（EXtensible Markup Language）
- XML 是一种标记语言，很类似 HTML
- XML 的设计宗旨是传输数据，而非显示数据
- XML 标签没有被预定义。您需要自行定义标签。
- XML 被设计为具有自我描述性。
- XML 是 W3C 的推荐标准
创建 XML 文件
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。
编辑 XML 文件
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
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。
JDOM 的用法
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
JDOM 的具体实现
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。
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