java多功能记事本

import java.awt.*;
import java.awt.event.*;
import java.text.*;
import java.util.*;
import java.io.*;
import javax.swing.undo.*;
import javax.swing.*;
import javax.swing.event.*;
import java.awt.datatransfer.*;
import java.util.List;

public class Notepad4 extends JFrame implements ActionListener, DocumentListener 
  {  JMenu mFile, mEdit, mMode, mView, mHelp;
      // ---------------文件菜单
JMenuItem mFile_New, mFile_Open, mFile_Save, mFile_ASave, mFile_Print, mFile_Exit;
// ---------------编辑菜单
JMenuItem mEdit_Undo, mEdit_Cut, mEdit_Copy, mEdit_Paste, mEdit_Del, mEdit_Search, mEdit_SearchNext, mEdit_Replace, mEdit_Turnto, mEdit_SelectAll, mEdit_TimeDate;
// ---------------格式菜单
JCheckBoxMenuItem formatMenu_LineWrap;
JMenu formatMenu_Color;
JMenuItem formatMenu_Font, formatMenu_Color_FgColor, formatMenu_Color_BgColor;
// ---------------查看菜单
JCheckBoxMenuItem viewMenu_Status;
// ---------------帮助菜单
JMenuItem mHelp_HelpTopics, mHelp_About;
// ---------------弹出菜单级菜单项
JPopupMenu popupMenu;
JMenuItem popupMenu_Undo, popupMenu_Cut, popupMenu_Copy, popupMenu_Paste, popupMenu_Delete, popupMenu_SelectAll;
// ---------------工具栏按钮
JButton newButton, openButton, saveButton, saveAsButton, printButton, undoButton, redoButton, cutButton, copyButton, pasteButton, deleteButton, searchButton, timeButton, fontButton, boldButton,

italicButton, fgcolorButton, bgcolorButton, helpButton;
// 文本编辑区域
static JTextArea Text;
// 状态栏标签
JLabel statusLabel1, statusLabel2, statusLabel3;
JToolBar statusBar;
// ---------------系统剪贴板
Toolkit toolKit = Toolkit.getDefaultToolkit();
Clipboard clipBoard = toolKit.getSystemClipboard();
// ---------------创建撤消操作管理器
protected UndoManager undo = new UndoManager();
protected UndoableEditListener undoHandler = new UndoHandler();
// ----------------其它变量
boolean isNewFile = true; // 是否新文件(未保存过的)
File currentFile; // 当前文件名
String oldValue; // 存放编辑区原来的内容，用于比较文本是否有改动
JButton fontOkButton; // 字体设置里的"确定"按钮
// ----------------设置编辑区默认字体
protected Font defaultFont = new Font("宋体", Font.PLAIN, 12);
GregorianCalendar time = new GregorianCalendar();
int hour = time.get(Calendar.HOUR_OF_DAY);
int min = time.get(Calendar.MINUTE);
int second = time.get(Calendar.SECOND);
File saveFileName = null, fileName = null;

public Notepad4() {
super("VXBB的记事本");
setDefaultCloseOperation(DO_NOTHING_ON_CLOSE);
Container container = getContentPane();
// System.out.println(Text.getDragEnabled()); //支持自动拖放