Notepad Main

package notepad;

import java.awt.BorderLayout;
import java.awt.Component;
import javax.swing.ButtonGroup;
import javax.swing.JCheckBoxMenuItem;
import javax.swing.JFileChooser;
import javax.swing.JOptionPane;
import javax.swing.JPanel;
import javax.swing.JFrame;
import javax.swing.JMenuBar;
import javax.swing.JMenu;
import javax.swing.JMenuItem;
import javax.swing.JRadioButtonMenuItem;
import java.awt.GridLayout;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.event.MouseEvent;
import java.awt.event.MouseListener;
import java.awt.event.WindowAdapter;
import java.awt.event.WindowEvent;
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 java.util.Date;
import javax.swing.JLabel;
import javax.swing.JScrollPane;
import javax.swing.JTextArea;
import javax.swing.event.CaretEvent;
import javax.swing.event.CaretListener;

public class JNotepad extends JFrame implements Runnable, ActionListener, MouseListener, CaretListener
{
 private static final long serialVersionUID = 1L;

 private JPanel jContentPane, jStatusPanel;

 private JScrollPane jScrollNotepadPane;

 private JMenuBar jMenuBar;

 private JMenu jMenuFile, jMenuEdit, jMenuFormat, jMenuList;

 private JMenuItem jMenuNew, jMenuOpen, jMenuSave, jMenuAsSave, jMenuExit, jMenuFont;

 private JMenuItem jMenuCut, jMenuCopy, jMenuPaste, jMenuSelectAll, jMenuFind, jMenuDate;

 private JCheckBoxMenuItem jMenuWrap;

 private JRadioButtonMenuItem jRadioItem;

 private ButtonGroup group = new ButtonGroup();

 private JLabel jLabelFile, jLabelDate, jLabelLines;

 private JTextArea jNotepad;

 private JFileChooser fileChooser;

 private File fileInfo;

 private Find findText;

 private SetFont fontText;

 private StringBuilder sbTitle = new StringBuilder("无标题 - 记事本                    ");
 private StringBuilder sbText = new StringBuilder();

 private JMenuBar getJMainBar()
 {
  if (jMenuBar == null)
  {
   jMenuBar = new JMenuBar();
   jMenuBar.add(getJMenuFile());
   jMenuBar.add(getJMenuEdit());
   jMenuBar.add(getJMenuFormat());
   jMenuList = new JMenu("最近访问的文件(L)");
   jMenuList.setMnemonic('L');
   jMenuBar.add(jMenuList);
  }
  return jMenuBar;
 }

 @SuppressWarnings("deprecation")
 private JMenu getJMenuFile()
 {
  if (jMenuFile == null)
  {
   jMenuFile = new JMenu("文件(F)");
   jMenuFile.setMnemonic('F');
   jMenuNew = new JMenuItem("新建(N)");
   jMenuNew.setMnemonic('N');
   jMenuFile.add(jMenuNew).addActionListener(this);
   jMenuOpen = new JMenuItem("打开(O)");
   jMenuOpen.setMnemonic('O');
   jMenuFile.add(jMenuOpen).addActionListener(this);
   jMenuSave = new JMenuItem("保存(S)");
   jMenuSave.setMnemonic('S');
   jMenuSave.setEnabled(false);
   jMenuFile.add(jMenuSave).addActionListener(this);
   jMenuAsSave = new JMenuItem("另存为(A)");
   jMenuAsSave.setMnemonic('A');
   jMenuFile.add(jMenuAsSave).addActionListener(this);
   jMenuFile.addSeparator();
   jMenuExit = new JMenuItem("退出(X)");
   jMenuExit.setMnemonic('X');
   jMenuFile.add(jMenuExit).addActionListener(this);
  }
  return jMenuFile;
 }

 private JMenu getJMenuEdit()
 {
  if (jMenuEdit == null)
  {
   jMenuEdit = new JMenu("编辑(E)");
   jMenuEdit.setMnemonic('E');
   jMenuCut = new JMenuItem("剪切(T)");
   jMenuCut.setMnemonic('T');
   jMenuEdit.add(jMenuCut).addActionListener(this);
   jMenuCopy = new JMenuItem("复制(C)");
   jMenuCopy.setMnemonic('C');
   jMenuEdit.add(jMenuCopy).addActionListener(this);
   jMenuPaste = new JMenuItem("粘贴(P)");
   jMenuPaste.setMnemonic('P');
   jMenuEdit.add(jMenuPaste).addActionListener(this);
   jMenuSelectAll = new JMenuItem("全选(A)");
   jMenuSelectAll.setMnemonic('A');
   jMenuEdit.add(jMenuSelectAll).addActionListener(this);
   jMenuEdit.addSeparator();
   jMenuFind = new JMenuItem("查找/替换(F)");
   jMenuFind.setMnemonic('F');
   jMenuEdit.add(jMenuFind).addActionListener(this);
   jMenuEdit.addSeparator();
   jMenuDate = new JMenuItem("时间/日期(D)");
   jMenuDate.setMnemonic('D');
   jMenuEdit.add(jMenuDate).addActionListener(this);
  }
  return jMenuEdit;
 }

 private JMenu getJMenuFormat()
 {
  if (jMenuFormat == null)
  {
   jMenuFormat = new JMenu("格式(O)");
   jMenuFormat.setMnemonic('O');
   jMenuWrap = new JCheckBoxMenuItem("自动换行(W)", true); // jMenuWrap.setState(true);
   jMenuWrap.setMnemonic('W');
   jMenuFormat.add(jMenuWrap).addActionListener(this);
   jMenuFont = new JMenuItem("字体(F)");
   jMenuFont.setMnemonic('F');
   jMenuFormat.add(jMenuFont).addActionListener(this);
  }
  return jMenuFormat;
 }

 private JPanel getJStatusPanel()
 {
  if (jStatusPanel == null)
  {
   jLabelFile = new JLabel(" ");
   jLabelDate = new JLabel(" ");
   jLabelLines = new JLabel("总行数 1");
   GridLayout gridLayout = new GridLayout();
   gridLayout.setRows(1);
   jStatusPanel = new JPanel();
   jStatusPanel.setLayout(gridLayout);
   jStatusPanel.add(jLabelFile, null);
   jStatusPanel.add(jLabelDate, null);
   jStatusPanel.add(jLabelLines, null);
  }
  return jStatusPanel;
 }

 private JScrollPane getJScrollNotepadPane()
 {
  if (jScrollNotepadPane == null)
  {
   jScrollNotepadPane = new JScrollPane();
   jNotepad = new JTextArea();
   jNotepad.setLineWrap(true); // 设置自动换行
   jNotepad.setWrapStyleWord(true);
   jNotepad.addCaretListener(this);
   jScrollNotepadPane.setViewportView(jNotepad);
  }
  return jScrollNotepadPane;
 }

 public static void main(String[] args)
 {
  JNotepad notepad = new JNotepad();
  Thread thread = new Thread(notepad);
  thread.run();
  thread.start();
 }

 public JNotepad()
 {
  this.setJMenuBar(getJMainBar());
  this.setContentPane(getJContentPane());
  this.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
  this.setBounds(100,100, 800, 560);
  this.setVisible(true);
  this.addWindowListener(new WindowAdapter()
  {
   public void windowClosing(WindowEvent e)
   {
    toFileList(false);
   }
  });
  toFileList(true);
  fileChooser = new JFileChooser();    // 创建文件对话框的对象
  fileChooser.setSize(400, 300);
 }

 private JPanel getJContentPane()
 {
  if (jContentPane == null)
  {
   jContentPane = new JPanel();
   jContentPane.setLayout(new BorderLayout());
   jContentPane.add(getJStatusPanel(), BorderLayout.SOUTH);
   jContentPane.add(getJScrollNotepadPane(), BorderLayout.CENTER);
  }
  return jContentPane;
 }
 /**
  * 读取或写入最近访问的文件的路径。
  * @param flag：True 表示读取，False 表示写入。
  */
 private void toFileList(boolean flag)
 {
  File fileList = new File("notepad//FileList.txt");
  try
  {
   if(flag)
   {
    if(fileList.exists())
    {
     String line = null; // null 不能替换为 "" 。
     FileReader fr = new FileReader(fileList);
     BufferedReader br = new BufferedReader(fr);
     while((line = br.readLine()) != null)
     {
      jRadioItem = new JRadioButtonMenuItem(line);
      group.add(jRadioItem);
      jMenuList.add(jRadioItem).addMouseListener(this);
     }
     br.close();
     fr.close();
    }
   }
   else
   {
    if(!fileList.exists())
     fileList.createNewFile();
    FileWriter fw = new FileWriter(fileList);
    BufferedWriter bw = new BufferedWriter(fw);
    for(Component item : jMenuList.getMenuComponents())
    {
     bw.write(((JRadioButtonMenuItem)item).getText());
     bw.newLine();
    }
    bw.close();
    fw.close();
   }
  }
  catch(IOException ie)
  {
   ie.printStackTrace();
  }
 }
 /**
  * 读取选定文件的内容。
  * @param file：选定的文件的对象。
  */
 private void toFileReader(File file)
 {
  try
  {
   FileReader fr = new FileReader(fileInfo = file);
   BufferedReader br = new BufferedReader(fr);
   jNotepad.read(br, null); // 读取所有字符。
   br.close();
   fr.close();
   sbTitle.delete(0, sbTitle.length());
   sbTitle.append(fileInfo.getName());
   sbTitle.append("                    ");
   this.setTitle(null);
   jMenuSave.setEnabled(true);
   jNotepad.setCaretPosition(1); // 更新总行数。
  }
  catch(IOException ie)
  {
   ie.printStackTrace();
  }
 }
 /**
  * 写入当前文本的内容。
  * @param file：选定的文件的对象。
  */
 private void toFileWriter(File file)
 {
  try
  {
   FileWriter fw = new FileWriter(file);
   BufferedWriter bw = new BufferedWriter(fw);
   jNotepad.write(bw); // 逐行写入。
   bw.close();
   fw.close();
  }
  catch(IOException ie)
  {
   ie.printStackTrace();
  }
 }

 public void run()
 {
  while(true)
  {
   try
   {
    if (this.getTitle().length() < sbTitle.length())
     this.setTitle(sbTitle.substring(0, this.getTitle().length() + 1));
    else
    {
     sbTitle.append(sbTitle.charAt(0));
     this.setTitle(sbTitle.deleteCharAt(0).toString());
    }
    jLabelDate.setText(String.format("%1$tA %1$tB %1$td %1$tY, %1$tp %1$tl:%1$tM:%1$tS", new Date()));
    if(fileInfo != null && fileInfo.exists())
    {
     sbText.append("文件属性：");
     if (!fileInfo.canWrite() && fileInfo.isHidden())
      sbText.append("只读，隐藏");
     else if (!fileInfo.canWrite())
      sbText.append("只读");
     else if (fileInfo.isHidden())
      sbText.append("隐藏");
     else
      sbText.append("正常");
    }
    else
     sbText.append("文件不存在");
    jLabelFile.setText(sbText.toString());
    sbText.delete(0, sbText.length());
    Thread.sleep(200);
   }
   catch (InterruptedException e)
   {
    e.printStackTrace();
   }
  }
 }

 public void actionPerformed(ActionEvent e)
 {
  if (e.getSource().equals(jMenuExit))
   System.exit(0);
  else if (e.getSource().equals(jMenuNew))
  {
   if(JOptionPane.showConfirmDialog(this, "当前文本内容以改变，是否新建？", "记事本", JOptionPane.YES_NO_OPTION, JOptionPane.QUESTION_MESSAGE) == 0)
   {
    sbTitle.delete(0, sbTitle.length());
    sbTitle.append("无标题 - 记事本                    ");
    this.setTitle(null);
   }
  }
  else if (e.getSource().equals(jMenuOpen))
  {
   if(fileChooser.showOpenDialog(this) == JFileChooser.APPROVE_OPTION)
   {
    toFileReader(fileChooser.getSelectedFile());
    jRadioItem = new JRadioButtonMenuItem(fileInfo.getPath());
    group.add(jRadioItem);
    jMenuList.add(jRadioItem).addMouseListener(this);
   }
  }
  else if(e.getSource().equals(jMenuSave))
  {
   if(fileInfo.canWrite())    // 文件属性是否为只读
    toFileWriter(fileInfo);
   else
    JOptionPane.showMessageDialog(this, String.format("文件“%s”的属性为只读，请先更改其属性。", fileInfo.getPath()));
  }
  else if(e.getSource().equals(jMenuAsSave))
  {
   if(fileChooser.showSaveDialog(this) == JFileChooser.APPROVE_OPTION)
   {
    File file = fileChooser.getSelectedFile();
    if(file.exists())
    {
     if(JOptionPane.showConfirmDialog(this, String.format("文件“%s”已存在，要替换它吗？", file.getPath()), "记事本", JOptionPane.YES_NO_OPTION, JOptionPane.QUESTION_MESSAGE) == 1)
      return;
     if(!file.canWrite())
     {
      JOptionPane.showMessageDialog(this, String.format("文件“%s”的属性为只读，请先更改其属性。", file.getPath()));
      return;
     }
    }
    toFileWriter(file);
   }
  }
  else if(e.getSource().equals(jMenuFind))
  {
   if(findText == null)
    findText = new Find(this, jNotepad);
   findText.setVisible(true);
  }
  else if(e.getSource().equals(jMenuFont))
  {
   if(fontText == null)
    fontText = new SetFont(this, jNotepad);
   fontText.setVisible(true);
  }
  else if(e.getSource().equals(jMenuCut))
  {
   jNotepad.cut();
  }
  else if(e.getSource().equals(jMenuCopy))
  {
   jNotepad.copy();
  }
  else if(e.getSource().equals(jMenuPaste))
  {
   jNotepad.paste();
  }
  else if(e.getSource().equals(jMenuSelectAll))
  {
   jNotepad.selectAll();
  }
  else if(e.getSource().equals(jMenuDate))
  {
   jNotepad.insert(String.format("%1$tF %1$tT", new Date()), jNotepad.getSelectionStart());
  }
  else if(e.getSource().equals(jMenuWrap))
  {
   jNotepad.setLineWrap(!jNotepad.getLineWrap());    // 自动换行
  }
 }

 public void mouseReleased(MouseEvent e)  // 处理鼠标释放事件
 {
  JRadioButtonMenuItem item = (JRadioButtonMenuItem)e.getSource();
  switch(e.getButton()) // 鼠标右键。
  {
   case 1:
    File file = new File(item.getText());
    if(file.exists())
     toFileReader(file);
    else
     JOptionPane.showMessageDialog(this, String.format("文件“%s”不存在！", item.getText()));
    break;
   case 3:
    if(JOptionPane.showConfirmDialog(this, String.format("确实要删除“%s”吗？", item.getText()), "记事本", JOptionPane.YES_NO_OPTION, JOptionPane.QUESTION_MESSAGE) == 0)
     jMenuList.remove(item);
    break;
   default:
    break;
  }

 }
 public void mouseClicked(MouseEvent e)
 {}

 public void mouseEntered(MouseEvent e)
 {}

 public void mouseExited(MouseEvent e)
 {}

 public void mousePressed(MouseEvent e)
 {}

 public void caretUpdate(CaretEvent e)
 {
  jLabelLines.setText(String.format("总行数 %d", jNotepad.getLineCount()));
 }
}