/* HTMLDocumentEditor.java
* @author: Charles Bell
* @version: May 27, 2002
*/

import java.awt.*;
import java.awt.event.*;
import java.io.*;

import javax.swing.*;
import javax.swing.event.*;
import javax.swing.filechooser.*;
import javax.swing.text.*;
import javax.swing.text.html.*;
import javax.swing.undo.*;

/**HTML文件文檔編輯器*/
public class HTMLDocumentEditor extends JFrame implements ActionListener
{
 /** 聲明一個網頁文檔對象變量*/
 private HTMLDocument document;
 /** 創建一個文本編輯板*/
 private JTextPane textPane = new JTextPane();
 private boolean debug = false;
 /** 聲明一個文件對象變量*/
 private File currentFile;
 
 /** 偵聽在當前文檔上的編輯器 */
 protected UndoableEditListener undoHandler = new UndoHandler();
 
 /** 添加撤消管理器 */
 protected UndoManager undo = new UndoManager();
 
 /** 添加撤消偵聽器*/
 private UndoAction undoAction = new UndoAction();
 /** 添加恢復偵聽器*/
 private RedoAction redoAction = new RedoAction();
 
 /** 添加剪切偵聽器*/
 private Action cutAction = new DefaultEditorKit.CutAction();
 /** 添加復制偵聽器*/
 private Action copyAction = new DefaultEditorKit.CopyAction();
 /** 添加粘貼偵聽器*/
 private Action pasteAction = new DefaultEditorKit.PasteAction();
 
 /** 添加加粗偵聽器*/
 private Action boldAction = new StyledEditorKit.BoldAction();
 /** 添加加下劃線偵聽器*/
 private Action underlineAction = new StyledEditorKit.UnderlineAction();
 /** 添加傾斜偵聽器*/
 private Action italicAction = new StyledEditorKit.ItalicAction();
 
 private Action insertBreakAction = new DefaultEditorKit.InsertBreakAction();
 private HTMLEditorKit.InsertHTMLTextAction unorderedListAction = new HTMLEditorKit.InsertHTMLTextAction("Bullets", "<ul><li> </li></ul>",HTML.Tag.P,HTML.Tag.UL);
 private HTMLEditorKit.InsertHTMLTextAction bulletAction = new HTMLEditorKit.InsertHTMLTextAction("Bullets", "<li> </li>",HTML.Tag.UL,HTML.Tag.LI);
 
 /** 構造方法*/
 public HTMLDocumentEditor()
 {
  /** 設置主窗體標題*/
  super("HTMLDocumentEditor");
  HTMLEditorKit editorKit = new HTMLEditorKit();
  /** 創建默認文檔指向網頁引用document*/
  document = (HTMLDocument)editorKit.createDefaultDocument();
  
  // 強制SWINGSET實現跨平臺，不改變風格
  try
  {
   UIManager.setLookAndFeel(UIManager.getCrossPlatformLookAndFeelClassName());
   // 如果你想用系統的界面風格替代，請注釋掉上一行代碼，而取消下一行代碼的注釋：
   //UIManager.setLookAndFeel(UIManager.getSystemLookAndFeelClassName());
  }
  catch (Exception exc)
  {
   //產生異常，則顯示錯誤消息：加載L&F錯誤
   System.err.println("Error loading L&F: " + exc);
  }
  
  //調用初始化方法
  init();
 }
 
 /**主方法，起動程序*/
 public static void main(String[] args)
 {
  //創建一個類的實例，即創建一個網頁編輯器
  HTMLDocumentEditor editor = new HTMLDocumentEditor();
 }
 
 /**初始化各組件的方法*/
 public void init()
 {
  //調用自定義繼承WindowListener的偵聽器FrameListener，給主窗體添加WindowListener
  addWindowListener(new FrameListener());
  
  JMenuBar menuBar = new JMenuBar();
  getContentPane().add(menuBar, BorderLayout.NORTH);
  JMenu fileMenu = new JMenu("File");  //文件
  JMenu editMenu = new JMenu("Edit");  //編輯
  JMenu colorMenu = new JMenu("Color");  //顏色
  JMenu fontMenu = new JMenu("Font");  //字體
  JMenu styleMenu = new JMenu("Style");  //樣式
  JMenu alignMenu = new JMenu("Align");  //對齊
  JMenu helpMenu = new JMenu("Help");  //幫助
  
  menuBar.add(fileMenu);
  menuBar.add(editMenu);
  menuBar.add(colorMenu);
  menuBar.add(fontMenu);
  menuBar.add(styleMenu);
  menuBar.add(alignMenu);
  menuBar.add(helpMenu);
  
  JMenuItem newItem = new JMenuItem("New", new ImageIcon("whatsnew-bang.gif"));  //新建
  JMenuItem openItem = new JMenuItem("Open",new ImageIcon("open.gif"));    //打開
  JMenuItem saveItem = new JMenuItem("Save",new ImageIcon("save.gif"));    //保存
  JMenuItem saveAsItem = new JMenuItem("Save As");         //另存
  JMenuItem exitItem = new JMenuItem("Exit",new ImageIcon("exit.gif"));    //退出
  
  newItem.addActionListener(this);
  openItem.addActionListener(this);
  saveItem.addActionListener(this);
  saveAsItem.addActionListener(this);
  exitItem.addActionListener(this);
  
  fileMenu.add(newItem);
  fileMenu.add(openItem);
  fileMenu.add(saveItem);
  fileMenu.add(saveAsItem);
  fileMenu.add(exitItem);
  
  //給菜單項添加偵聽器
  JMenuItem undoItem = new JMenuItem(undoAction);      //撤消
  JMenuItem redoItem = new JMenuItem(redoAction);      //恢復
  JMenuItem cutItem = new JMenuItem(cutAction);       //剪切
  JMenuItem copyItem = new JMenuItem(copyAction);      //復制
  JMenuItem pasteItem = new JMenuItem(pasteAction);      //粘貼
  JMenuItem clearItem = new JMenuItem("Clear");       //清除
  JMenuItem selectAllItem = new JMenuItem("Select All");     //全選
  JMenuItem insertBreaKItem = new JMenuItem(insertBreakAction);   
  JMenuItem unorderedListItem = new JMenuItem(unorderedListAction);
  JMenuItem bulletItem = new JMenuItem(bulletAction);     //項目符號
  
  cutItem.setText("Cut");
  copyItem.setText("Copy");
  pasteItem.setText("Paste");
  insertBreaKItem.setText("Break");
  cutItem.setIcon(new ImageIcon("cut.gif"));
  copyItem.setIcon(new ImageIcon("copy.gif"));
  pasteItem.setIcon(new ImageIcon("paste.gif"));
  insertBreaKItem.setIcon(new ImageIcon("break.gif"));
  unorderedListItem.setIcon(new ImageIcon("bullets.gif"));
  
  clearItem.addActionListener(this);
  selectAllItem.addActionListener(this);
  
  editMenu.add(undoItem);
  editMenu.add(redoItem);
  editMenu.add(cutItem);
  editMenu.add(copyItem);
  editMenu.add(pasteItem);
  editMenu.add(clearItem);
  editMenu.add(selectAllItem);
  editMenu.add(insertBreaKItem);
  editMenu.add(unorderedListItem);
  editMenu.add(bulletItem);
  
  JMenuItem redTextItem = new JMenuItem(new StyledEditorKit.ForegroundAction("Red",Color.red));
  JMenuItem orangeTextItem = new JMenuItem(new StyledEditorKit.ForegroundAction("Orange",Color.orange));
  JMenuItem yellowTextItem = new JMenuItem(new StyledEditorKit.ForegroundAction("Yellow",Color.yellow));
  JMenuItem greenTextItem = new JMenuItem(new StyledEditorKit.ForegroundAction("Green",Color.green));
  JMenuItem blueTextItem = new JMenuItem(new StyledEditorKit.ForegroundAction("Blue",Color.blue));
  JMenuItem cyanTextItem = new JMenuItem(new StyledEditorKit.ForegroundAction("Cyan",Color.cyan));
  JMenuItem magentaTextItem = new JMenuItem(new StyledEditorKit.ForegroundAction("Magenta",Color.magenta));
  JMenuItem blackTextItem = new JMenuItem(new StyledEditorKit.ForegroundAction("Black",Color.black));
  
  redTextItem.setIcon(new ImageIcon("red.gif"));
  orangeTextItem.setIcon(new ImageIcon("orange.gif"));
  yellowTextItem.setIcon(new ImageIcon("yellow.gif"));
  greenTextItem.setIcon(new ImageIcon("green.gif"));
  blueTextItem.setIcon(new ImageIcon("blue.gif"));
  cyanTextItem.setIcon(new ImageIcon("cyan.gif"));
  magentaTextItem.setIcon(new ImageIcon("magenta.gif"));
  blackTextItem.setIcon(new ImageIcon("black.gif"));
  
  colorMenu.add(redTextItem);
  colorMenu.add(orangeTextItem);
  colorMenu.add(yellowTextItem);
  colorMenu.add(greenTextItem);
  colorMenu.add(blueTextItem);
  colorMenu.add(cyanTextItem);
  colorMenu.add(magentaTextItem);
  colorMenu.add(blackTextItem);
  
  JMenu fontTypeMenu = new JMenu("Font Type");
  fontMenu.add(fontTypeMenu);
  
  String[] fontTypes = {"SansSerif", "Serif", "Monospaced", "Dialog", "DialogInput"};
  for (int i = 0; i < fontTypes.length;i++)
  {
   if (debug) System.out.println(fontTypes[i]);
   JMenuItem nextTypeItem = new JMenuItem(fontTypes[i]);
   nextTypeItem.setAction(new StyledEditorKit.FontFamilyAction(fontTypes[i], fontTypes[i]));
   fontTypeMenu.add(nextTypeItem);
  }
 
  JMenu fontSizeMenu = new JMenu("Font Size");
  fontMenu.add(fontSizeMenu);
  
  int[] fontSizes = {6, 8,10,12,14, 16, 20,24, 32,36,48,72};
  for (int i = 0; i < fontSizes.length;i++)
  {
   if (debug) System.out.println(fontSizes[i]);
   JMenuItem nextSizeItem = new JMenuItem(String.valueOf(fontSizes[i]));
   nextSizeItem.setAction(new StyledEditorKit.FontSizeAction(String.valueOf(fontSizes[i]), fontSizes[i]));
   fontSizeMenu.add(nextSizeItem);
  }
  
  
  JMenuItem boldMenuItem = new JMenuItem(boldAction);
  JMenuItem underlineMenuItem = new JMenuItem(underlineAction);
  JMenuItem italicMenuItem = new JMenuItem(italicAction);
 
  boldMenuItem.setText("Bold");
  underlineMenuItem.setText("Underline");
  italicMenuItem.setText("Italic");
  
  boldMenuItem.setIcon(new ImageIcon("bold.gif"));
  underlineMenuItem.setIcon(new ImageIcon("underline.gif"));
  italicMenuItem.setIcon(new ImageIcon("italic.gif"));
  
  styleMenu.add(boldMenuItem);
  styleMenu.add(underlineMenuItem);
  styleMenu.add(italicMenuItem);
  
  JMenuItem subscriptMenuItem = new JMenuItem(new SubscriptAction());
  JMenuItem superscriptMenuItem = new JMenuItem(new SuperscriptAction());
  JMenuItem strikeThroughMenuItem = new JMenuItem(new StrikeThroughAction());
  
  subscriptMenuItem.setText("Subscript");
  superscriptMenuItem.setText("Superscript");
  strikeThroughMenuItem.setText("StrikeThrough");
  
  subscriptMenuItem.setIcon(new ImageIcon("subscript.gif"));
  superscriptMenuItem.setIcon(new ImageIcon("superscript.gif"));
  strikeThroughMenuItem.setIcon(new ImageIcon("strikethough.gif"));
  
  styleMenu.add(subscriptMenuItem);
  styleMenu.add(superscriptMenuItem);
  styleMenu.add(strikeThroughMenuItem);
  
  JMenuItem leftAlignMenuItem = new JMenuItem(new StyledEditorKit.AlignmentAction("Left Align",StyleConstants.ALIGN_LEFT));
  JMenuItem centerMenuItem = new JMenuItem(new StyledEditorKit.AlignmentAction("Center",StyleConstants.ALIGN_CENTER));
  JMenuItem rightAlignMenuItem = new JMenuItem(new StyledEditorKit.AlignmentAction ("Right Align",StyleConstants.ALIGN_RIGHT));
  
  leftAlignMenuItem.setText("Left Align");
  centerMenuItem.setText("Center");
  rightAlignMenuItem.setText("Right Align");
  
  leftAlignMenuItem.setIcon(new ImageIcon("left.gif"));
  centerMenuItem.setIcon(new ImageIcon("center.gif"));
  rightAlignMenuItem.setIcon(new ImageIcon("right.gif"));
  
  alignMenu.add(leftAlignMenuItem);
  alignMenu.add(centerMenuItem);
  alignMenu.add(rightAlignMenuItem);
  
  JMenuItem helpItem = new JMenuItem("幫助");
  helpItem.addActionListener(this);
  helpMenu.add(helpItem);
  
  JMenuItem shortcutsItem = new JMenuItem("Keyboard Shortcuts");
  shortcutsItem.addActionListener(this);
  helpMenu.add(shortcutsItem);
  
  JMenuItem aboutItem = new JMenuItem("About QuantumHyperSpace");
  aboutItem.addActionListener(this);
  helpMenu.add(aboutItem);
  
  
  JPanel editorControlPanel = new JPanel();
  //editorControlPanel.setLayout(new GridLayout(3,3));
  editorControlPanel.setLayout(new FlowLayout());
  
  /* 按鈕 */
  JButton cutButton = new JButton(cutAction);    //創建“剪切”按鈕，添加剪切偵聽
  JButton copyButton = new JButton(copyAction);    //創建“復制”按鈕，添加復制偵
  JButton pasteButton = new JButton(pasteAction);   //創建“粘貼”按鈕，添加粘貼偵
  
  JButton boldButton = new JButton(boldAction);    //創建“加粗”按鈕，添加加粗偵聽
  JButton underlineButton = new JButton(underlineAction); //創建“下劃線”按鈕，添加下劃線偵聽
  JButton italicButton = new JButton(italicAction);   //創建“斜體”按鈕，添加斜體偵聽
  
  
  //JButton insertButton = new JButton(insertAction);
  //JButton insertBreakButton = new JButton(insertBreakAction);
  //JButton tabButton = new JButton(tabAction);
  
  cutButton.setText("Cut");
  copyButton.setText("Copy");
  pasteButton.setText("Paste");
  
  boldButton.setText("Bold");
  underlineButton.setText("Underline");
  italicButton.setText("Italic");
  
  //insertButton.setText("Insert");
  //insertBreakButton.setText("Insert Break");
  //tabButton.setText("Tab");
  
  cutButton.setIcon(new ImageIcon("cut.gif"));
  copyButton.setIcon(new ImageIcon("copy.gif"));
  pasteButton.setIcon(new ImageIcon("paste.gif"));
  
  boldButton.setIcon(new ImageIcon("bold.gif"));
  underlineButton.setIcon(new ImageIcon("underline.gif"));
  italicButton.setIcon(new ImageIcon("italic.gif"));
  
  editorControlPanel.add(cutButton);
  editorControlPanel.add(copyButton);
  editorControlPanel.add(pasteButton);
  
  editorControlPanel.add(boldButton);
  editorControlPanel.add(underlineButton);
  editorControlPanel.add(italicButton);
  
  
  //editorControlPanel.add(insertButton);
  //editorControlPanel.add(insertBreakButton);
  //editorControlPanel.add(tabButton);
  
  JButton subscriptButton = new JButton(new SubscriptAction());
  JButton superscriptButton = new JButton(new SuperscriptAction());
  JButton strikeThroughButton = new JButton(new StrikeThroughAction());
  
  subscriptButton.setIcon(new ImageIcon("subscript.gif"));
  superscriptButton.setIcon(new ImageIcon("superscript.gif"));
  strikeThroughButton.setIcon(new ImageIcon("strikethough.gif"));
  
  
  JPanel specialPanel = new JPanel();
  specialPanel.setLayout(new FlowLayout());
  
  specialPanel.add(subscriptButton);
  specialPanel.add(superscriptButton);
  specialPanel.add(strikeThroughButton);
  
  //JButton leftAlignButton = new JButton(new AlignLeftAction());
  //JButton centerButton = new JButton(new CenterAction());
  //JButton rightAlignButton = new JButton(new AlignRightAction());
  
  JButton leftAlignButton = new JButton(new StyledEditorKit.AlignmentAction("Left Align",StyleConstants.ALIGN_LEFT));
  JButton centerButton = new JButton(new StyledEditorKit.AlignmentAction("Center",StyleConstants.ALIGN_CENTER));
  JButton rightAlignButton = new JButton(new StyledEditorKit.AlignmentAction ("Right Align",StyleConstants.ALIGN_RIGHT));
  JButton colorButton = new JButton(new StyledEditorKit.AlignmentAction ("Right Align",StyleConstants.ALIGN_RIGHT));
  
  leftAlignButton.setIcon(new ImageIcon("left.gif"));
  centerButton.setIcon(new ImageIcon("center.gif"));
  rightAlignButton.setIcon(new ImageIcon("right.gif"));
  colorButton.setIcon(new ImageIcon("color.gif"));
  
  leftAlignButton.setText("Left Align");
  centerButton.setText("Center");
  rightAlignButton.setText("Right Align");
  
  JPanel alignPanel = new JPanel();
  alignPanel.setLayout(new FlowLayout());
  alignPanel.add(leftAlignButton);
  alignPanel.add(centerButton);
  alignPanel.add(rightAlignButton);
  
  document.addUndoableEditListener(undoHandler);
  resetUndoManager();
  
  textPane = new JTextPane(document);
  textPane.setContentType("text/html");
  JScrollPane scrollPane = new JScrollPane(textPane);
  Dimension screenSize = Toolkit.getDefaultToolkit().getScreenSize();
  Dimension scrollPaneSize = new Dimension(5*screenSize.width/8,5*screenSize.height/8);
  scrollPane.setPreferredSize(scrollPaneSize);
  
  //創建工具欄面板，并設置面板布局管理器，添加子面板
  JPanel toolPanel = new JPanel();
  toolPanel.setLayout(new BorderLayout());
  toolPanel.add(editorControlPanel, BorderLayout.NORTH);
  toolPanel.add(specialPanel, BorderLayout.CENTER);
  toolPanel.add(alignPanel, BorderLayout.SOUTH);
  
  //向主窗體添加菜單欄
  getContentPane().add(menuBar, BorderLayout.NORTH);
  //向主窗體添加工具欄
  getContentPane().add(toolPanel, BorderLayout.CENTER);
  //向主窗體添加滾動面板
  getContentPane().add(scrollPane, BorderLayout.SOUTH);
  pack();
  setLocationRelativeTo(null);
  startNewDocument();
  show();
 }
 
 public void actionPerformed(ActionEvent ae)
 {
  String actionCommand = ae.getActionCommand();
  if (debug)
  {
   int modifier = ae.getModifiers();
   long when = ae.getWhen();
   String parameter = ae.paramString();
   System.out.println("actionCommand: " + actionCommand);
   System.out.println("modifier: " + modifier);
   System.out.println("when: " + when);
   System.out.println("parameter: " + parameter);
  }
  if (actionCommand.compareTo("New") == 0)
  {
   startNewDocument();
  }
  else if (actionCommand.compareTo("Open") == 0)
  {
   openDocument();
  }
  else if (actionCommand.compareTo("Save") == 0)
  {
   saveDocument();
  }
  else if (actionCommand.compareTo("Save As") == 0)
  {
   saveDocumentAs();
  }
  else if (actionCommand.compareTo("Exit") == 0)
  {
   exit();
  }
  else if (actionCommand.compareTo("Clear") == 0)
  {
   clear();
  }
  else if (actionCommand.compareTo("Select All") == 0)
  {
   selectAll();
  }
  else if (actionCommand.compareTo("幫助") == 0)
  {
   help();
  }
  else if (actionCommand.compareTo("Keyboard Shortcuts") == 0)
  {
   showShortcuts();
  }
  else if (actionCommand.compareTo("About QuantumHyperSpace") == 0)
  {
   aboutQuantumHyperSpace();
  }
 }
 
 public void startNewDocument()
 {
  Document oldDoc = textPane.getDocument();
  if(oldDoc != null)
  oldDoc.removeUndoableEditListener(undoHandler);
  HTMLEditorKit editorKit = new HTMLEditorKit();
  document = (HTMLDocument)editorKit.createDefaultDocument();
  textPane.setDocument(document);
  currentFile = null;
  setTitle("HTMLDocumentEditor");
  textPane.getDocument().addUndoableEditListener(undoHandler);
  resetUndoManager();
 }
 
 public void openDocument()
 {
  try
  {
   File current = new File(".");
   JFileChooser chooser = new JFileChooser(current);
   chooser.setFileSelectionMode(JFileChooser.FILES_AND_DIRECTORIES);
   chooser.setFileFilter(new HTMLFileFilter());
   int approval = chooser.showSaveDialog(this);
   if (approval == JFileChooser.APPROVE_OPTION)
   {
    currentFile = chooser.getSelectedFile();
    setTitle(currentFile.getName());
    FileReader fr = new FileReader(currentFile);
    Document oldDoc = textPane.getDocument();
    if(oldDoc != null)
    oldDoc.removeUndoableEditListener(undoHandler);
    HTMLEditorKit editorKit = new HTMLEditorKit();
    document = (HTMLDocument)editorKit.createDefaultDocument();
    editorKit.read(fr,document,0);
    document.addUndoableEditListener(undoHandler);
    textPane.setDocument(document);
    resetUndoManager();
   }
  }
  catch(BadLocationException ble)
  {
   System.err.println("BadLocationException: " + ble.getMessage());
  }
  catch(FileNotFoundException fnfe)
  {
   System.err.println("FileNotFoundException: " + fnfe.getMessage());
  }
  catch(IOException ioe)
  {
   System.err.println("IOException: " + ioe.getMessage());
  }
 }
 
 public void saveDocument()
 {
  if (currentFile != null)
  {
   try
   {
    FileWriter fw = new FileWriter(currentFile);
    fw.write(textPane.getText());
    fw.close();
   }
   catch(FileNotFoundException fnfe)
   {
    System.err.println("FileNotFoundException: " + fnfe.getMessage());
   }
   catch(IOException ioe)
   {
    System.err.println("IOException: " + ioe.getMessage());
   }
  }
  else
  {
   saveDocumentAs();
  }
 }
 
 public void saveDocumentAs()
 {
  try
  {
   File current = new File(".");
   JFileChooser chooser = new JFileChooser(current);
   chooser.setFileSelectionMode(JFileChooser.FILES_AND_DIRECTORIES);
   chooser.setFileFilter(new HTMLFileFilter());
   int approval = chooser.showSaveDialog(this);
   if (approval == JFileChooser.APPROVE_OPTION)
   {
    File newFile = chooser.getSelectedFile();
    if (newFile.exists())
    {
     String message = newFile.getAbsolutePath() + " already exists. \n" + "Do you want to replace it?";
     if (JOptionPane.showConfirmDialog(this, message) == JOptionPane.YES_OPTION)
     {
      currentFile = newFile;
      setTitle(currentFile.getName());
      FileWriter fw = new FileWriter(currentFile);
      fw.write(textPane.getText());
      fw.close();
      if (debug) System.out.println("Saved " + currentFile.getAbsolutePath());
     }
    }
    else
    {
     currentFile = new File(newFile.getAbsolutePath());
     setTitle(currentFile.getName());
     FileWriter fw = new FileWriter(currentFile);
     fw.write(textPane.getText());
     fw.close();
     if (debug) System.out.println("Saved " + currentFile.getAbsolutePath());
    }
   }
  }
  catch(FileNotFoundException fnfe)
  {
   System.err.println("FileNotFoundException: " + fnfe.getMessage());
  }
  catch(IOException ioe)
  {
   System.err.println("IOException: " + ioe.getMessage());
  }
 }
 
 public void exit()
 {
  String exitMessage = "Are you sure you want to exit?";
  if (JOptionPane.showConfirmDialog(this, exitMessage) == JOptionPane.YES_OPTION)
  {
   System.exit(0);
  }
 }
 
 /**調用startNewDocument()方法，清除當前文本，開始一個新文檔*/
 public void clear()
 {
  startNewDocument();
 }
 
 /**調用JTextPane的全選方法*/
 public void selectAll()
 {
  textPane.selectAll();
 }
 
 /**利用消息框顯示幫助信息*/
 public void help()
 {
  JOptionPane.showMessageDialog(this,"DocumentEditor.java\n" + "Author: Charles Bell\n" + "Version: May 25, 2002\n" +
           " }
 
 /**利用消息框顯示快捷鍵*/
 public void showShortcuts()
 {
  String shortcuts = "Navigate in | Tab\n" + "Navigate out | Ctrl+Tab\n" + "Navigate out backwards | Shift+Ctrl+Tab\n" +
  "Move up/down a line | Up/Down Arrown\n" + "Move left/right a component or char | Left/Right Arrow\n" +
  "Move up/down one vertical block | PgUp/PgDn\n" + "Move to start/end of line | Home/End\n" +
  "Move to previous/next word | Ctrl+Left/Right Arrow\n" + "Move to start/end of data | Ctrl+Home/End\n" +
  "Move left/right one block | Ctrl+PgUp/PgDn\n" + "Select All | Ctrl+A\n" +
  "Extend selection up one line | Shift+Up Arrow\n" + "Extend selection down one line | Shift+Down Arrow\n" +
  "Extend selection to beginning of line | Shift+Home\n" + "Extend selection to end of line | Shift+End\n" +
  "Extend selection to beginning of data | Ctrl+Shift+Home\n" + "Extend selection to end of data | Ctrl+Shift+End\n" +
  "Extend selection left | Shift+Right Arrow\n" + "Extend selection right | Shift+Right Arrow\n" +
  "Extend selection up one vertical block | Shift+PgUp\n" + "Extend selection down one vertical block | Shift+PgDn\n" +
  "Extend selection left one block | Ctrl+Shift+PgUp\n" + "Extend selection right one block | Ctrl+Shift+PgDn\n" +
  "Extend selection left one word | Ctrl+Shift+Left Arrow\n" + "Extend selection right one word | Ctrl+Shift+Right Arrow\n";
  JOptionPane.showMessageDialog(this,shortcuts);
 }
 
 public void aboutQuantumHyperSpace()
 {
  JOptionPane.showMessageDialog(this,"QuantumHyperSpace Programming Services\n" + "  "email: support@quantumhyperspace.com\n" +  " or \n" + "email: charles@quantumhyperspace.com\n",
  "QuantumHyperSpace",JOptionPane.INFORMATION_MESSAGE, new ImageIcon("quantumhyperspace.gif"));
 }
 
 /**內部類：自定義繼承WindowListener的偵聽器FrameListener*/
 class FrameListener extends WindowAdapter
 {
  /**處理點擊窗體關閉按鈕事件，實現程序的關閉停止*/
  public void windowClosing(WindowEvent we)
  {
   exit();
  }
 }
 
 class SubscriptAction extends StyledEditorKit.StyledTextAction
 {
 
  public SubscriptAction()
  {
   super(StyleConstants.Subscript.toString());
  }
  public void actionPerformed(ActionEvent ae)
  {
   JEditorPane editor = getEditor(ae);
   if (editor != null)
   {
    StyledEditorKit kit = getStyledEditorKit(editor);
    MutableAttributeSet attr = kit.getInputAttributes();
    boolean subscript = (StyleConstants.isSubscript(attr)) ? false : true;
    SimpleAttributeSet sas = new SimpleAttributeSet();
    StyleConstants.setSubscript(sas, subscript);
    setCharacterAttributes(editor, sas, false);
   }
  }
 }

 class SuperscriptAction extends StyledEditorKit.StyledTextAction
 {
 
  public SuperscriptAction()
  {
   super(StyleConstants.Superscript.toString());
  }
  public void actionPerformed(ActionEvent ae)
  {
   JEditorPane editor = getEditor(ae);
   if (editor != null)
   {
    StyledEditorKit kit = getStyledEditorKit(editor);
    MutableAttributeSet attr = kit.getInputAttributes();
    boolean superscript = (StyleConstants.isSuperscript(attr)) ? false : true;
    SimpleAttributeSet sas = new SimpleAttributeSet();
    StyleConstants.setSuperscript(sas, superscript);
    setCharacterAttributes(editor, sas, false);
   }
  }
 }

 class StrikeThroughAction extends StyledEditorKit.StyledTextAction
 {
  public StrikeThroughAction()
  {
   super(StyleConstants.StrikeThrough.toString());
  }
  
  public void actionPerformed(ActionEvent ae)
  {
   JEditorPane editor = getEditor(ae);
   if (editor != null)
   {
    StyledEditorKit kit = getStyledEditorKit(editor);
    MutableAttributeSet attr = kit.getInputAttributes();
    boolean strikeThrough = (StyleConstants.isStrikeThrough(attr)) ? false : true;
    SimpleAttributeSet sas = new SimpleAttributeSet();
    StyleConstants.setStrikeThrough(sas, strikeThrough);
    setCharacterAttributes(editor, sas, false);
   }
  }
 }

 class HTMLFileFilter extends javax.swing.filechooser.FileFilter
 {
  public boolean accept(File f)
  {
   return ((f.isDirectory()) ||(f.getName().toLowerCase().indexOf(".htm") > 0));
  }
  
  public String getDescription()
  {
   return "html";
  }
 }
 
 protected void resetUndoManager()
 {
  undo.discardAllEdits();
  undoAction.update();
  redoAction.update();
 }

 class UndoHandler implements UndoableEditListener
 {
  /**
  * Messaged when the Document has created an edit, the edit is
  * added to <code>undo</code>, an instance of UndoManager.
  */
  public void undoableEditHappened(UndoableEditEvent e)
  {
   undo.addEdit(e.getEdit());
   undoAction.update();
   redoAction.update();
  }
 }

 class UndoAction extends AbstractAction
 {
  public UndoAction()
  {
   super("Undo");
   setEnabled(false);
  }
  
  public void actionPerformed(ActionEvent e)
  {
   try
   {
    undo.undo();
   }
   catch (CannotUndoException ex)
   {
    System.out.println("Unable to undo: " + ex);
    ex.printStackTrace();
   }
   update();
   redoAction.update();
  }
 
  protected void update()
  {
   if(undo.canUndo())
   {
    setEnabled(true);
    putValue(Action.NAME, undo.getUndoPresentationName());
   }
   else
   {
    setEnabled(false);
    putValue(Action.NAME, "Undo");
   }
  }
 }

 class RedoAction extends AbstractAction
 {
 
  public RedoAction()
  {
   super("Redo");
   setEnabled(false);
  }
  
  public void actionPerformed(ActionEvent e)
  {
   try
   {
    undo.redo();
   }
   catch (CannotRedoException ex)
   {
    System.err.println("Unable to redo: " + ex);
    ex.printStackTrace();
   }
   update();
   undoAction.update();
  }
  
  protected void update()
  {
   if(undo.canRedo())
   {
    setEnabled(true);
    putValue(Action.NAME, undo.getRedoPresentationName());
   }
   else
   {
    setEnabled(false);
    putValue(Action.NAME, "Redo");
   }
  }
 }
}