项目总结——简单的记事本

野性酷女 2023-02-10 11:29 194阅读 0赞

## java程序之记事本程序代码 ##

import java.awt.*;
     import java.awt.event.*;
     import java.text.*;
     import java.util.*;
     import java.io.*;
     import javax.swing.undo.*;
     import javax.swing.border.*;
     import javax.swing.*;
     import javax.swing.text.*;
     import javax.swing.event.*;
    import java.awt.datatransfer.*;
    
    
    public class Notepad extends JFrame implements ActionListener,DocumentListener
    { 	//菜单
    	JMenu fileMenu,editMenu,formatMenu,viewMenu,helpMenu;
    	//右键弹出菜单项
    	JPopupMenu popupMenu;
    	JMenuItem popupMenu_Undo,popupMenu_Cut,popupMenu_Copy,popupMenu_Paste,popupMenu_Delete,popupMenu_SelectAll;
    	//“文件”的菜单项
    	JMenuItem fileMenu_New,fileMenu_Open,fileMenu_Save,fileMenu_SaveAs,fileMenu_PageSetUp,fileMenu_Print,fileMenu_Exit;
    	//“编辑”的菜单项
    	JMenuItem editMenu_Undo,editMenu_Cut,editMenu_Copy,editMenu_Paste,editMenu_Delete,editMenu_Find,editMenu_FindNext,editMenu_Replace,editMenu_GoTo,editMenu_SelectAll,editMenu_TimeDate;
    	//“格式”的菜单项
    	JCheckBoxMenuItem formatMenu_LineWrap;
    	JMenuItem formatMenu_Font;
    	//“查看”的菜单项
    	JCheckBoxMenuItem viewMenu_Status;
    	//“帮助”的菜单项
    	JMenuItem helpMenu_HelpTopics,helpMenu_AboutNotepad;
    	//“文本”编辑区域
    	JTextArea editArea;
    	//状态栏标签
    	JLabel statusLabel;
    	//系统剪贴板
    	Toolkit toolkit=Toolkit.getDefaultToolkit();
    	Clipboard clipBoard=toolkit.getSystemClipboard();
    	//创建撤销操作管理器(与撤销操作有关)
    	protected UndoManager undo=new UndoManager();
    	protected UndoableEditListener undoHandler=new UndoHandler();
    	//其他变量
    	String oldValue;//存放编辑区原来的内容，用于比较文本是否有改动
    	boolean isNewFile=true;//是否新文件(未保存过的)
    	File currentFile;//当前文件名
    	//构造函数开始
    	public Notepad()
    	{ 	
    		super("Java记事本");
    		//改变系统默认字体
    		Font font = new Font("Dialog", Font.PLAIN, 12);
    		java.util.Enumeration keys = UIManager.getDefaults().keys();
    		while (keys.hasMoreElements()) { 
    			Object key = keys.nextElement();
    			Object value = UIManager.get(key);
    			if (value instanceof javax.swing.plaf.FontUIResource) { 
    				UIManager.put(key, font);
    			}
    		}
    		//创建菜单条
    		JMenuBar menuBar=new JMenuBar();
    		//创建文件菜单及菜单项并注册事件监听
    		fileMenu=new JMenu("文件(F)");
    		fileMenu.setMnemonic('F');//设置快捷键ALT+F
    
    		fileMenu_New=new JMenuItem("新建(N)");
    		fileMenu_New.setAccelerator(KeyStroke.getKeyStroke(KeyEvent.VK_N,InputEvent.CTRL_MASK));
    		fileMenu_New.addActionListener(this);
    
    		fileMenu_Open=new JMenuItem("打开(O)...");
    		fileMenu_Open.setAccelerator(KeyStroke.getKeyStroke(KeyEvent.VK_O,InputEvent.CTRL_MASK));
    		fileMenu_Open.addActionListener(this);
    
    		fileMenu_Save=new JMenuItem("保存(S)");
    		fileMenu_Save.setAccelerator(KeyStroke.getKeyStroke(KeyEvent.VK_S,InputEvent.CTRL_MASK));
    		fileMenu_Save.addActionListener(this);
    
    		fileMenu_SaveAs=new JMenuItem("另存为(A)...");
    		fileMenu_SaveAs.addActionListener(this);
    
    		fileMenu_PageSetUp=new JMenuItem("页面设置(U)...");
    		fileMenu_PageSetUp.addActionListener(this);
    
    		fileMenu_Print=new JMenuItem("打印(P)...");
    		fileMenu_Print.setAccelerator(KeyStroke.getKeyStroke(KeyEvent.VK_P, InputEvent.CTRL_MASK)); 
    		fileMenu_Print.addActionListener(this);
    
    		fileMenu_Exit=new JMenuItem("退出(X)");
    		fileMenu_Exit.addActionListener(this);
    
    		//创建编辑菜单及菜单项并注册事件监听
    		editMenu=new JMenu("编辑(E)");
    		editMenu.setMnemonic('E');//设置快捷键ALT+E
    		//当选择编辑菜单时，设置剪切、复制、粘贴、删除等功能的可用性
    		editMenu.addMenuListener(new MenuListener()
    		{ 	public void menuCanceled(MenuEvent e)//取消菜单时调用
    			{ 	checkMenuItemEnabled();//设置剪切、复制、粘贴、删除等功能的可用性
    			}
    			public void menuDeselected(MenuEvent e)//取消选择某个菜单时调用
    			{ 	checkMenuItemEnabled();//设置剪切、复制、粘贴、删除等功能的可用性
    			}
    			public void menuSelected(MenuEvent e)//选择某个菜单时调用
    			{ 	checkMenuItemEnabled();//设置剪切、复制、粘贴、删除等功能的可用性
    			}
    		});
    
    		editMenu_Undo=new JMenuItem("撤销(U)");
    		editMenu_Undo.setAccelerator(KeyStroke.getKeyStroke(KeyEvent.VK_Z,InputEvent.CTRL_MASK));
    		editMenu_Undo.addActionListener(this);
    		editMenu_Undo.setEnabled(false);
    
    		editMenu_Cut=new JMenuItem("剪切(T)");
    		editMenu_Cut.setAccelerator(KeyStroke.getKeyStroke(KeyEvent.VK_X,InputEvent.CTRL_MASK));
    		editMenu_Cut.addActionListener(this);
    
    		editMenu_Copy=new JMenuItem("复制(C)");
    		editMenu_Copy.setAccelerator(KeyStroke.getKeyStroke(KeyEvent.VK_C,InputEvent.CTRL_MASK));
    		editMenu_Copy.addActionListener(this);
    
    		editMenu_Paste=new JMenuItem("粘贴(P)");
    		editMenu_Paste.setAccelerator(KeyStroke.getKeyStroke(KeyEvent.VK_V,InputEvent.CTRL_MASK));
    		editMenu_Paste.addActionListener(this);
    
    		editMenu_Delete=new JMenuItem("删除(D)");
    		editMenu_Delete.setAccelerator(KeyStroke.getKeyStroke(KeyEvent.VK_DELETE,0));
    		editMenu_Delete.addActionListener(this);
    
    		editMenu_Find=new JMenuItem("查找(F)...");
    		editMenu_Find.setAccelerator(KeyStroke.getKeyStroke(KeyEvent.VK_F,InputEvent.CTRL_MASK));
    		editMenu_Find.addActionListener(this);
    
    		editMenu_FindNext=new JMenuItem("查找下一个(N)");
    		editMenu_FindNext.setAccelerator(KeyStroke.getKeyStroke(KeyEvent.VK_F3,0));
    		editMenu_FindNext.addActionListener(this);
    
    		editMenu_Replace = new JMenuItem("替换(R)...",'R'); 
    		editMenu_Replace.setAccelerator(KeyStroke.getKeyStroke(KeyEvent.VK_H, InputEvent.CTRL_MASK)); 
    		editMenu_Replace.addActionListener(this);
    
    		editMenu_GoTo = new JMenuItem("转到(G)...",'G'); 
    		editMenu_GoTo.setAccelerator(KeyStroke.getKeyStroke(KeyEvent.VK_G, InputEvent.CTRL_MASK)); 
    		editMenu_GoTo.addActionListener(this);
    
    		editMenu_SelectAll = new JMenuItem("全选",'A'); 
    		editMenu_SelectAll.setAccelerator(KeyStroke.getKeyStroke(KeyEvent.VK_A, InputEvent.CTRL_MASK)); 
    		editMenu_SelectAll.addActionListener(this);
    
    		editMenu_TimeDate = new JMenuItem("时间/日期(D)",'D');
    		editMenu_TimeDate.setAccelerator(KeyStroke.getKeyStroke(KeyEvent.VK_F5,0));
    		editMenu_TimeDate.addActionListener(this);
    
    		//创建格式菜单及菜单项并注册事件监听
    		formatMenu=new JMenu("格式(O)");
    		formatMenu.setMnemonic('O');//设置快捷键ALT+O
    
    		formatMenu_LineWrap=new JCheckBoxMenuItem("自动换行(W)");
    		formatMenu_LineWrap.setMnemonic('W');//设置快捷键ALT+W
    		formatMenu_LineWrap.setState(true);
    		formatMenu_LineWrap.addActionListener(this);
    
    		formatMenu_Font=new JMenuItem("字体(F)...");
    		formatMenu_Font.addActionListener(this);
    
    		//创建查看菜单及菜单项并注册事件监听
    		viewMenu=new JMenu("查看(V)");
    		viewMenu.setMnemonic('V');//设置快捷键ALT+V
    
    		viewMenu_Status=new JCheckBoxMenuItem("状态栏(S)");
    		viewMenu_Status.setMnemonic('S');//设置快捷键ALT+S
    		viewMenu_Status.setState(true);
    		viewMenu_Status.addActionListener(this);
    
    		//创建帮助菜单及菜单项并注册事件监听
    		helpMenu = new JMenu("帮助(H)");
    		helpMenu.setMnemonic('H');//设置快捷键ALT+H
    
    		helpMenu_HelpTopics = new JMenuItem("帮助主题(H)"); 
    		helpMenu_HelpTopics.setAccelerator(KeyStroke.getKeyStroke(KeyEvent.VK_F1,0));
    		helpMenu_HelpTopics.addActionListener(this);
    
    		helpMenu_AboutNotepad = new JMenuItem("关于记事本(A)"); 
    		helpMenu_AboutNotepad.addActionListener(this);
    
    		//向菜单条添加"文件"菜单及菜单项
    		menuBar.add(fileMenu); 
    		fileMenu.add(fileMenu_New); 
    		fileMenu.add(fileMenu_Open); 
    		fileMenu.add(fileMenu_Save); 
    		fileMenu.add(fileMenu_SaveAs); 
    		fileMenu.addSeparator();		//分隔线
    		fileMenu.add(fileMenu_PageSetUp); 
    		fileMenu.add(fileMenu_Print); 
    		fileMenu.addSeparator();		//分隔线 
    		fileMenu.add(fileMenu_Exit); 
    
    		//向菜单条添加"编辑"菜单及菜单项 
    		menuBar.add(editMenu); 
    		editMenu.add(editMenu_Undo);  
    		editMenu.addSeparator();		//分隔线 
    		editMenu.add(editMenu_Cut); 
    		editMenu.add(editMenu_Copy); 
    		editMenu.add(editMenu_Paste); 
    		editMenu.add(editMenu_Delete); 
    		editMenu.addSeparator(); 		//分隔线
    		editMenu.add(editMenu_Find); 
    		editMenu.add(editMenu_FindNext); 
    		editMenu.add(editMenu_Replace);
    		editMenu.add(editMenu_GoTo); 
    		editMenu.addSeparator();  		//分隔线
    		editMenu.add(editMenu_SelectAll); 
    		editMenu.add(editMenu_TimeDate);
    
    		//向菜单条添加"格式"菜单及菜单项 
    		menuBar.add(formatMenu); 
    		formatMenu.add(formatMenu_LineWrap); 
    		formatMenu.add(formatMenu_Font);
    
    		//向菜单条添加"查看"菜单及菜单项 
    		menuBar.add(viewMenu); 
    		viewMenu.add(viewMenu_Status);
    
    		//向菜单条添加"帮助"菜单及菜单项
    		menuBar.add(helpMenu);
    		helpMenu.add(helpMenu_HelpTopics);
    		helpMenu.addSeparator();
    		helpMenu.add(helpMenu_AboutNotepad);
    				
    		//向窗口添加菜单条 
    		this.setJMenuBar(menuBar);
    
    		//创建文本编辑区并添加滚动条
    		editArea=new JTextArea(20,50);
    		JScrollPane scroller=new JScrollPane(editArea);
    		scroller.setVerticalScrollBarPolicy(JScrollPane.VERTICAL_SCROLLBAR_ALWAYS);
    		this.add(scroller,BorderLayout.CENTER);//向窗口添加文本编辑区
    		editArea.setWrapStyleWord(true);//设置单词在一行不足容纳时换行
    		editArea.setLineWrap(true);//设置文本编辑区自动换行默认为true,即会"自动换行"
    		//this.add(editArea,BorderLayout.CENTER);//向窗口添加文本编辑区
    		oldValue=editArea.getText();//获取原文本编辑区的内容
    
    		//编辑区注册事件监听(与撤销操作有关)
    		editArea.getDocument().addUndoableEditListener(undoHandler);
    		editArea.getDocument().addDocumentListener(this);
    
    		//创建右键弹出菜单
    		popupMenu=new JPopupMenu();
    		popupMenu_Undo=new JMenuItem("撤销(U)");
    		popupMenu_Cut=new JMenuItem("剪切(T)");
    		popupMenu_Copy=new JMenuItem("复制(C)");
    		popupMenu_Paste=new JMenuItem("粘帖(P)");
    		popupMenu_Delete=new JMenuItem("删除(D)");
    		popupMenu_SelectAll=new JMenuItem("全选(A)");
    
    		popupMenu_Undo.setEnabled(false);
    
    		//向右键菜单添加菜单项和分隔符
    		popupMenu.add(popupMenu_Undo);
    		popupMenu.addSeparator();
    		popupMenu.add(popupMenu_Cut);
    		popupMenu.add(popupMenu_Copy);
    		popupMenu.add(popupMenu_Paste);
    		popupMenu.add(popupMenu_Delete);
    		popupMenu.addSeparator();
    		popupMenu.add(popupMenu_SelectAll);
    
    		//文本编辑区注册右键菜单事件
    		popupMenu_Undo.addActionListener(this);
    		popupMenu_Cut.addActionListener(this);
    		popupMenu_Copy.addActionListener(this);
    		popupMenu_Paste.addActionListener(this);
    		popupMenu_Delete.addActionListener(this);
    		popupMenu_SelectAll.addActionListener(this);
    
    		//文本编辑区注册右键菜单事件
    		editArea.addMouseListener(new MouseAdapter()
    		{ 	public void mousePressed(MouseEvent e)
    			{ 	if(e.isPopupTrigger())//返回此鼠标事件是否为该平台的弹出菜单触发事件
    				{ 	popupMenu.show(e.getComponent(),e.getX(),e.getY());//在组件调用者的坐标空间中的位置 X、Y 显示弹出菜单
    				}
    				checkMenuItemEnabled();//设置剪切，复制，粘帖，删除等功能的可用性
    				editArea.requestFocus();//编辑区获取焦点
    			}
    			public void mouseReleased(MouseEvent e)
    			{ 	if(e.isPopupTrigger())//返回此鼠标事件是否为该平台的弹出菜单触发事件
    				{ 	popupMenu.show(e.getComponent(),e.getX(),e.getY());//在组件调用者的坐标空间中的位置 X、Y 显示弹出菜单
    				}
    				checkMenuItemEnabled();//设置剪切，复制，粘帖，删除等功能的可用性
    				editArea.requestFocus();//编辑区获取焦点
    			}
    		});//文本编辑区注册右键菜单事件结束
    
    		//创建和添加状态栏
    		statusLabel=new JLabel("　按F1获取帮助");
    		this.add(statusLabel,BorderLayout.SOUTH);//向窗口添加状态栏标签
    
    		//设置窗口在屏幕上的位置、大小和可见性 
    		this.setLocation(100,100);
    		this.setSize(650,550);
    		this.setVisible(true);
    		//添加窗口监听器
    		addWindowListener(new WindowAdapter()
    		{ 	public void windowClosing(WindowEvent e)
    			{ 	exitWindowChoose();
    			}
    		});
    
    		checkMenuItemEnabled();
    		editArea.requestFocus();
    	}//构造函数Notepad结束
    	
    	//设置菜单项的可用性：剪切，复制，粘帖，删除功能
    	public void checkMenuItemEnabled()
    	{ 	String selectText=editArea.getSelectedText();
    		if(selectText==null)
    		{ 	editMenu_Cut.setEnabled(false);
    			popupMenu_Cut.setEnabled(false);
    			editMenu_Copy.setEnabled(false);
    			popupMenu_Copy.setEnabled(false);
    			editMenu_Delete.setEnabled(false);
    			popupMenu_Delete.setEnabled(false);
    		}
    		else
    		{ 	editMenu_Cut.setEnabled(true);
    			popupMenu_Cut.setEnabled(true); 
    			editMenu_Copy.setEnabled(true);
    			popupMenu_Copy.setEnabled(true);
    			editMenu_Delete.setEnabled(true);
    			popupMenu_Delete.setEnabled(true);
    		}
    		//粘帖功能可用性判断
    		Transferable contents=clipBoard.getContents(this);
    		if(contents==null)
    		{ 	editMenu_Paste.setEnabled(false);
    			popupMenu_Paste.setEnabled(false);
    		}
    		else
    		{ 	editMenu_Paste.setEnabled(true);
    			popupMenu_Paste.setEnabled(true);	
    		}
    	}//方法checkMenuItemEnabled()结束
    
    	//关闭窗口时调用
    	public void exitWindowChoose()
    	{ 	editArea.requestFocus();
    		String currentValue=editArea.getText();
    		if(currentValue.equals(oldValue)==true)
    		{ 	System.exit(0);
    		}
    		else
    		{ 	int exitChoose=JOptionPane.showConfirmDialog(this,"您的文件尚未保存，是否保存？","退出提示",JOptionPane.YES_NO_CANCEL_OPTION);
    			if(exitChoose==JOptionPane.YES_OPTION)
    			{ 	//boolean isSave=false;
    				if(isNewFile)
    				{ 	
    					String str=null;
    					JFileChooser fileChooser=new JFileChooser();
    					fileChooser.setFileSelectionMode(JFileChooser.FILES_ONLY);
    					fileChooser.setApproveButtonText("确定");
    					fileChooser.setDialogTitle("另存为");
    					
    					int result=fileChooser.showSaveDialog(this);
    					
    					if(result==JFileChooser.CANCEL_OPTION)
    					{ 	statusLabel.setText("　您没有保存文件");
    						return;
    					}					
    	
    					File saveFileName=fileChooser.getSelectedFile();
    				
    					if(saveFileName==null||saveFileName.getName().equals(""))
    					{ 	JOptionPane.showMessageDialog(this,"不合法的文件名","不合法的文件名",JOptionPane.ERROR_MESSAGE);
    					}
    					else 
    					{ 	try
    						{ 	FileWriter fw=new FileWriter(saveFileName);
    							BufferedWriter bfw=new BufferedWriter(fw);
    							bfw.write(editArea.getText(),0,editArea.getText().length());
    							bfw.flush();
    							fw.close();
    							
    							isNewFile=false;
    							currentFile=saveFileName;
    							oldValue=editArea.getText();
    							
    							this.setTitle(saveFileName.getName()+" - 记事本");
    							statusLabel.setText("　当前打开文件:"+saveFileName.getAbsoluteFile());
    							//isSave=true;
    						}							
    						catch(IOException ioException){ 					
    						}				
    					}
    				}
    				else
    				{ 
    					try
    					{ 	FileWriter fw=new FileWriter(currentFile);
    						BufferedWriter bfw=new BufferedWriter(fw);
    						bfw.write(editArea.getText(),0,editArea.getText().length());
    						bfw.flush();
    						fw.close();
    						//isSave=true;
    					}							
    					catch(IOException ioException){ 					
    					}
    				}
    				System.exit(0);
    				//if(isSave)System.exit(0);
    				//else return;
    			}
    			else if(exitChoose==JOptionPane.NO_OPTION)
    			{ 	System.exit(0);
    			}
    			else
    			{ 	return;
    			}
    		}
    	}//关闭窗口时调用方法结束
    
    	//查找方法
    	public void find()
    	{ 	final JDialog findDialog=new JDialog(this,"查找",false);//false时允许其他窗口同时处于激活状态(即无模式)
    		Container con=findDialog.getContentPane();//返回此对话框的contentPane对象 
    		con.setLayout(new FlowLayout(FlowLayout.LEFT));
    		JLabel findContentLabel=new JLabel("查找内容(N)：");
    		final JTextField findText=new JTextField(15);
    		JButton findNextButton=new JButton("查找下一个(F)：");
    		final JCheckBox matchCheckBox=new JCheckBox("区分大小写(C)");
    		ButtonGroup bGroup=new ButtonGroup();
    		final JRadioButton upButton=new JRadioButton("向上(U)");
    		final JRadioButton downButton=new JRadioButton("向下(U)");
    		downButton.setSelected(true);
    		bGroup.add(upButton);
    		bGroup.add(downButton);
    		/*ButtonGroup此类用于为一组按钮创建一个多斥（multiple-exclusion）作用域。 使用相同的 ButtonGroup 对象创建一组按钮意味着“开启”其中一个按钮时，将关闭组中的其他所有按钮。*/
    		/*JRadioButton此类实现一个单选按钮，此按钮项可被选择或取消选择，并可为用户显示其状态。 与 ButtonGroup 对象配合使用可创建一组按钮，一次只能选择其中的一个按钮。 （创建一个 ButtonGroup 对象并用其 add 方法将 JRadioButton 对象包含在此组中。）*/
    		JButton cancel=new JButton("取消");
    		//取消按钮事件处理
    		cancel.addActionListener(new ActionListener()
    		{ 	public void actionPerformed(ActionEvent e)
    			{ 	findDialog.dispose();
    			}
    		});
    		//"查找下一个"按钮监听
    		findNextButton.addActionListener(new ActionListener()
    		{ 	public void actionPerformed(ActionEvent e)
    			{ 	//"区分大小写(C)"的JCheckBox是否被选中
    				int k=0,m=0;
    				final String str1,str2,str3,str4,strA,strB;
    				str1=editArea.getText();
    				str2=findText.getText();
    				str3=str1.toUpperCase();
    				str4=str2.toUpperCase();
    				if(matchCheckBox.isSelected())//区分大小写
    				{ 	strA=str1;
    					strB=str2;
    				}
    				else//不区分大小写,此时把所选内容全部化成大写(或小写)，以便于查找 
    				{ 	strA=str3;
    					strB=str4;
    				}
    				if(upButton.isSelected())
    				{ 	//k=strA.lastIndexOf(strB,editArea.getCaretPosition()-1);
    					if(editArea.getSelectedText()==null)
    						k=strA.lastIndexOf(strB,editArea.getCaretPosition()-1);
    					else
    						k=strA.lastIndexOf(strB, editArea.getCaretPosition()-findText.getText().length()-1);	
    					if(k>-1)
    					{ 	//String strData=strA.subString(k,strB.getText().length()+1);
    						editArea.setCaretPosition(k);
    						editArea.select(k,k+strB.length());
    					}
    					else
    					{ 	JOptionPane.showMessageDialog(null,"找不到您查找的内容！","查找",JOptionPane.INFORMATION_MESSAGE);
    					}
    				}
    				else if(downButton.isSelected())
    				{ 	if(editArea.getSelectedText()==null)
    						k=strA.indexOf(strB,editArea.getCaretPosition()+1);
    					else
    						k=strA.indexOf(strB, editArea.getCaretPosition()-findText.getText().length()+1);	
    					if(k>-1)
    					{ 	//String strData=strA.subString(k,strB.getText().length()+1);
    						editArea.setCaretPosition(k);
    						editArea.select(k,k+strB.length());
    					}
    					else
    					{ 	JOptionPane.showMessageDialog(null,"找不到您查找的内容！","查找",JOptionPane.INFORMATION_MESSAGE);
    					}
    				}
    			}
    		});//"查找下一个"按钮监听结束
    		//创建"查找"对话框的界面
    		JPanel panel1=new JPanel();
    		JPanel panel2=new JPanel();
    		JPanel panel3=new JPanel();
    		JPanel directionPanel=new JPanel();
    		directionPanel.setBorder(BorderFactory.createTitledBorder("方向"));
    		//设置directionPanel组件的边框;
    		//BorderFactory.createTitledBorder(String title)创建一个新标题边框，使用默认边框（浮雕化）、默认文本位置（位于顶线上）、默认调整 (leading) 以及由当前外观确定的默认字体和文本颜色，并指定了标题文本。
    		directionPanel.add(upButton);
    		directionPanel.add(downButton);
    		panel1.setLayout(new GridLayout(2,1));
    		panel1.add(findNextButton);
    		panel1.add(cancel);
    		panel2.add(findContentLabel);
    		panel2.add(findText);
    		panel2.add(panel1);
    		panel3.add(matchCheckBox);
    		panel3.add(directionPanel);
    		con.add(panel2);
    		con.add(panel3);
    		findDialog.setSize(410,180);
    		findDialog.setResizable(false);//不可调整大小
    		findDialog.setLocation(230,280);
    		findDialog.setVisible(true);
    	}//查找方法结束
    	
    	//替换方法
    	public void replace()
    	{ 	final JDialog replaceDialog=new JDialog(this,"替换",false);//false时允许其他窗口同时处于激活状态(即无模式)
    		Container con=replaceDialog.getContentPane();//返回此对话框的contentPane对象
    		con.setLayout(new FlowLayout(FlowLayout.CENTER));
    		JLabel findContentLabel=new JLabel("查找内容(N)：");
    		final JTextField findText=new JTextField(15);
    		JButton findNextButton=new JButton("查找下一个(F):");
    		JLabel replaceLabel=new JLabel("替换为(P)：");
    		final JTextField replaceText=new JTextField(15);
    		JButton replaceButton=new JButton("替换(R)");
    		JButton replaceAllButton=new JButton("全部替换(A)");
    		JButton cancel=new JButton("取消");
    		cancel.addActionListener(new ActionListener()
    		{ 	public void actionPerformed(ActionEvent e)
    			{ 	replaceDialog.dispose();
    			}
    		});
    		final JCheckBox matchCheckBox=new JCheckBox("区分大小写(C)");
    		ButtonGroup bGroup=new ButtonGroup();
    		final JRadioButton upButton=new JRadioButton("向上(U)");
    		final JRadioButton downButton=new JRadioButton("向下(U)");
    		downButton.setSelected(true);
    		bGroup.add(upButton);
    		bGroup.add(downButton);
    		/*ButtonGroup此类用于为一组按钮创建一个多斥（multiple-exclusion）作用域。 使用相同的 ButtonGroup 对象创建一组按钮意味着“开启”其中一个按钮时，将关闭组中的其他所有按钮。*/
    		/*JRadioButton此类实现一个单选按钮，此按钮项可被选择或取消选择，并可为用户显示其状态。 与 ButtonGroup 对象配合使用可创建一组按钮，一次只能选择其中的一个按钮。 （创建一个 ButtonGroup 对象并用其 add 方法将 JRadioButton 对象包含在此组中。）*/
    		
    		//"查找下一个"按钮监听
    		findNextButton.addActionListener(new ActionListener()
    		{ 	public void actionPerformed(ActionEvent e)
    			{ 	//"区分大小写(C)"的JCheckBox是否被选中
    				int k=0,m=0;
    				final String str1,str2,str3,str4,strA,strB;
    				str1=editArea.getText();
    				str2=findText.getText();
    				str3=str1.toUpperCase();
    				str4=str2.toUpperCase();
    				if(matchCheckBox.isSelected())//区分大小写
    				{ 	strA=str1;
    					strB=str2;
    				}
    				else//不区分大小写,此时把所选内容全部化成大写(或小写)，以便于查找 
    				{ 	strA=str3;
    					strB=str4;
    				}
    				if(upButton.isSelected())
    				{ 	//k=strA.lastIndexOf(strB,editArea.getCaretPosition()-1);
    					if(editArea.getSelectedText()==null)
    						k=strA.lastIndexOf(strB,editArea.getCaretPosition()-1);
    					else
    						k=strA.lastIndexOf(strB, editArea.getCaretPosition()-findText.getText().length()-1);	
    					if(k>-1)
    					{ 	//String strData=strA.subString(k,strB.getText().length()+1);
    						editArea.setCaretPosition(k);
    						editArea.select(k,k+strB.length());
    					}
    					else
    					{ 	JOptionPane.showMessageDialog(null,"找不到您查找的内容！","查找",JOptionPane.INFORMATION_MESSAGE);
    					}
    				}
    				else if(downButton.isSelected())
    				{ 	if(editArea.getSelectedText()==null)
    						k=strA.indexOf(strB,editArea.getCaretPosition()+1);
    					else
    						k=strA.indexOf(strB, editArea.getCaretPosition()-findText.getText().length()+1);	
    					if(k>-1)
    					{ 	//String strData=strA.subString(k,strB.getText().length()+1);
    						editArea.setCaretPosition(k);
    						editArea.select(k,k+strB.length());
    					}
    					else
    					{ 	JOptionPane.showMessageDialog(null,"找不到您查找的内容！","查找",JOptionPane.INFORMATION_MESSAGE);
    					}
    				}
    			}
    		});//"查找下一个"按钮监听结束
    		
    		//"替换"按钮监听
    		replaceButton.addActionListener(new ActionListener()
    		{ 	public void actionPerformed(ActionEvent e)
    			{ 	if(replaceText.getText().length()==0 && editArea.getSelectedText()!=null) 
    					editArea.replaceSelection(""); 
    				if(replaceText.getText().length()>0 && editArea.getSelectedText()!=null) 
    					editArea.replaceSelection(replaceText.getText());
    			}
    		});//"替换"按钮监听结束
    		
    		//"全部替换"按钮监听
    		replaceAllButton.addActionListener(new ActionListener()
    		{ 	public void actionPerformed(ActionEvent e)
    			{ 	editArea.setCaretPosition(0);	//将光标放到编辑区开头 
    				int k=0,m=0,replaceCount=0;
    				if(findText.getText().length()==0)
    				{ 	JOptionPane.showMessageDialog(replaceDialog,"请填写查找内容!","提示",JOptionPane.WARNING_MESSAGE);
    					findText.requestFocus(true);
    					return;
    				}
    				while(k>-1)//当文本中有内容被选中时(k>-1被选中)进行替换，否则不进行while循环
    				{ 	//"区分大小写(C)"的JCheckBox是否被选中
    					//int k=0,m=0;
    					final String str1,str2,str3,str4,strA,strB;
    					str1=editArea.getText();
    					str2=findText.getText();
    					str3=str1.toUpperCase();
    					str4=str2.toUpperCase();
    					if(matchCheckBox.isSelected())//区分大小写
    					{ 	strA=str1;
    						strB=str2;
    					}
    					else//不区分大小写,此时把所选内容全部化成大写(或小写)，以便于查找 
    					{ 	strA=str3;
    						strB=str4;
    					}
    					if(upButton.isSelected())
    					{ 	//k=strA.lastIndexOf(strB,editArea.getCaretPosition()-1);
    						if(editArea.getSelectedText()==null)
    							k=strA.lastIndexOf(strB,editArea.getCaretPosition()-1);
    						else
    							k=strA.lastIndexOf(strB, editArea.getCaretPosition()-findText.getText().length()-1);	
    						if(k>-1)
    						{ 	//String strData=strA.subString(k,strB.getText().length()+1);
    							editArea.setCaretPosition(k);
    							editArea.select(k,k+strB.length());
    						}
    						else
    						{ 	if(replaceCount==0)
    							{ 	JOptionPane.showMessageDialog(replaceDialog, "找不到您查找的内容!", "记事本",JOptionPane.INFORMATION_MESSAGE); 
    							}
    							else
    							{ 	JOptionPane.showMessageDialog(replaceDialog,"成功替换"+replaceCount+"个匹配内容!","替换成功",JOptionPane.INFORMATION_MESSAGE);
    							}
    						}
    					}
    					else if(downButton.isSelected())
    					{ 	if(editArea.getSelectedText()==null)
    							k=strA.indexOf(strB,editArea.getCaretPosition()+1);
    						else
    							k=strA.indexOf(strB, editArea.getCaretPosition()-findText.getText().length()+1);	
    						if(k>-1)
    						{ 	//String strData=strA.subString(k,strB.getText().length()+1);
    							editArea.setCaretPosition(k);
    							editArea.select(k,k+strB.length());
    						}
    						else
    						{ 	if(replaceCount==0)
    							{ 	JOptionPane.showMessageDialog(replaceDialog, "找不到您查找的内容!", "记事本",JOptionPane.INFORMATION_MESSAGE); 
    							}
    							else
    							{ 	JOptionPane.showMessageDialog(replaceDialog,"成功替换"+replaceCount+"个匹配内容!","替换成功",JOptionPane.INFORMATION_MESSAGE);
    							}
    						}
    					}
    					if(replaceText.getText().length()==0 && editArea.getSelectedText()!= null)
    					{ 	editArea.replaceSelection("");
    						replaceCount++;
    					} 
    					
    					if(replaceText.getText().length()>0 && editArea.getSelectedText()!= null) 
    					{ 	editArea.replaceSelection(replaceText.getText()); 
    						replaceCount++;
    					}
    				}//while循环结束
    			}
    		});//"替换全部"方法结束
    		
    		//创建"替换"对话框的界面
    		JPanel directionPanel=new JPanel();
    		directionPanel.setBorder(BorderFactory.createTitledBorder("方向"));
    		//设置directionPanel组件的边框;
    		//BorderFactory.createTitledBorder(String title)创建一个新标题边框，使用默认边框（浮雕化）、默认文本位置（位于顶线上）、默认调整 (leading) 以及由当前外观确定的默认字体和文本颜色，并指定了标题文本。
    		directionPanel.add(upButton);
    		directionPanel.add(downButton);
    		JPanel panel1=new JPanel();
    		JPanel panel2=new JPanel();
    		JPanel panel3=new JPanel();
    		JPanel panel4=new JPanel();
    		panel4.setLayout(new GridLayout(2,1));
    		panel1.add(findContentLabel);
    		panel1.add(findText);
    		panel1.add(findNextButton);
    		panel4.add(replaceButton);
    		panel4.add(replaceAllButton);
    		panel2.add(replaceLabel);
    		panel2.add(replaceText);
    		panel2.add(panel4);
    		panel3.add(matchCheckBox);
    		panel3.add(directionPanel);
    		panel3.add(cancel);
    		con.add(panel1);
    		con.add(panel2);
    		con.add(panel3);
    		replaceDialog.setSize(420,220);
    		replaceDialog.setResizable(false);//不可调整大小
    		replaceDialog.setLocation(230,280);
    		replaceDialog.setVisible(true);
    	}//"全部替换"按钮监听结束
    
    	//"字体"方法
    	public void font()
    	{ 	final JDialog fontDialog=new JDialog(this,"字体设置",false);
    		Container con=fontDialog.getContentPane();
    		con.setLayout(new FlowLayout(FlowLayout.LEFT));
    		JLabel fontLabel=new JLabel("字体(F)：");
    		fontLabel.setPreferredSize(new Dimension(100,20));//构造一个Dimension，并将其初始化为指定宽度和高度
    		JLabel styleLabel=new JLabel("字形(Y)：");
    		styleLabel.setPreferredSize(new Dimension(100,20));
    		JLabel sizeLabel=new JLabel("大小(S)：");
    		sizeLabel.setPreferredSize(new Dimension(100,20));
    		final JLabel sample=new JLabel("张选仲的记事本-ZXZ's Notepad");
    		//sample.setHorizontalAlignment(SwingConstants.CENTER);
    		final JTextField fontText=new JTextField(9);
    		fontText.setPreferredSize(new Dimension(200,20));
    		final JTextField styleText=new JTextField(8);
    		styleText.setPreferredSize(new Dimension(200,20));
    		final int style[]={ Font.PLAIN,Font.BOLD,Font.ITALIC,Font.BOLD+Font.ITALIC};
    		final JTextField sizeText=new JTextField(5);
    		sizeText.setPreferredSize(new Dimension(200,20));
    		JButton okButton=new JButton("确定");
    		JButton cancel=new JButton("取消");
    		cancel.addActionListener(new ActionListener()
    		{ 	public void actionPerformed(ActionEvent e)
    			{ 	fontDialog.dispose();	
    			}
    		});
    		Font currentFont=editArea.getFont();
    		fontText.setText(currentFont.getFontName());
    		fontText.selectAll();
    		//styleText.setText(currentFont.getStyle());
    		//styleText.selectAll();
    		if(currentFont.getStyle()==Font.PLAIN)
    			styleText.setText("常规");
    		else if(currentFont.getStyle()==Font.BOLD)
    			styleText.setText("粗体");
    		else if(currentFont.getStyle()==Font.ITALIC)
    			styleText.setText("斜体");
    		else if(currentFont.getStyle()==(Font.BOLD+Font.ITALIC))
    			styleText.setText("粗斜体");
    		styleText.selectAll();
    		String str=String.valueOf(currentFont.getSize());
    		sizeText.setText(str);
    		sizeText.selectAll();
    		final JList fontList,styleList,sizeList;
    		GraphicsEnvironment ge=GraphicsEnvironment.getLocalGraphicsEnvironment();
    		final String fontName[]=ge.getAvailableFontFamilyNames();
    		fontList=new JList(fontName);
    		fontList.setFixedCellWidth(86);
    		fontList.setFixedCellHeight(20);
    		fontList.setSelectionMode(ListSelectionModel.SINGLE_SELECTION);
    		final String fontStyle[]={ "常规","粗体","斜体","粗斜体"};
    		styleList=new JList(fontStyle);
    		styleList.setFixedCellWidth(86);
    		styleList.setFixedCellHeight(20);
    		styleList.setSelectionMode(ListSelectionModel.SINGLE_SELECTION);
    		if(currentFont.getStyle()==Font.PLAIN)
    			styleList.setSelectedIndex(0);
    		else if(currentFont.getStyle()==Font.BOLD)
    			styleList.setSelectedIndex(1);
    		else if(currentFont.getStyle()==Font.ITALIC)
    			styleList.setSelectedIndex(2);
    		else if(currentFont.getStyle()==(Font.BOLD+Font.ITALIC))
    			styleList.setSelectedIndex(3);
    		final String fontSize[]={ "8","9","10","11","12","14","16","18","20","22","24","26","28","36","48","72"};
    		sizeList=new JList(fontSize);
    		sizeList.setFixedCellWidth(43);
    		sizeList.setFixedCellHeight(20);
    		sizeList.setSelectionMode(ListSelectionModel.SINGLE_SELECTION);
    		fontList.addListSelectionListener(new ListSelectionListener()
    		{ 	public void valueChanged(ListSelectionEvent event)
    			{ 	fontText.setText(fontName[fontList.getSelectedIndex()]);
    				fontText.selectAll();
    				Font sampleFont1=new Font(fontText.getText(),style[styleList.getSelectedIndex()],Integer.parseInt(sizeText.getText()));
    				sample.setFont(sampleFont1);
    			}
    		});
    		styleList.addListSelectionListener(new ListSelectionListener()
    		{ 	public void valueChanged(ListSelectionEvent event)
    			{ 	int s=style[styleList.getSelectedIndex()];
    				styleText.setText(fontStyle[s]);
    				styleText.selectAll();
    				Font sampleFont2=new Font(fontText.getText(),style[styleList.getSelectedIndex()],Integer.parseInt(sizeText.getText()));
    				sample.setFont(sampleFont2);
    			}
    		});
    		sizeList.addListSelectionListener(new ListSelectionListener()
    		{ 	public void valueChanged(ListSelectionEvent event)
    			{ 	sizeText.setText(fontSize[sizeList.getSelectedIndex()]);
    				//sizeText.requestFocus();
    				sizeText.selectAll();	
    				Font sampleFont3=new Font(fontText.getText(),style[styleList.getSelectedIndex()],Integer.parseInt(sizeText.getText()));
    				sample.setFont(sampleFont3);
    			}
    		});
    		okButton.addActionListener(new ActionListener()
    		{ 	public void actionPerformed(ActionEvent e)
    			{ 	Font okFont=new Font(fontText.getText(),style[styleList.getSelectedIndex()],Integer.parseInt(sizeText.getText()));
    				editArea.setFont(okFont);
    				fontDialog.dispose();
    			}
    		});
    		JPanel samplePanel=new JPanel();
    		samplePanel.setBorder(BorderFactory.createTitledBorder("示例"));
    		//samplePanel.setLayout(new FlowLayout(FlowLayout.CENTER));
    		samplePanel.add(sample);
    		JPanel panel1=new JPanel();
    		JPanel panel2=new JPanel();
    		JPanel panel3=new JPanel();
    		//JPanel panel4=new JPanel();
    		//JPanel panel5=new JPanel();
    		//panel1.add(fontLabel);
    		//panel1.add(styleLabel);
    		//panel1.add(sizeLabel);
    		//panel2.add(fontText);
    		//panel2.add(new JScrollPane(fontList));//JList不支持直接滚动，所以要让JList作为JScrollPane的视口视图
    		//panel2.setLayout(new GridLayout(2,1));
    		//panel3.add(styleText);
    		//panel3.add(new JScrollPane(styleList));
    		//panel3.setLayout(new GridLayout(2,1));
    		//panel4.add(sizeText);
    		//panel4.add(new JScrollPane(sizeText));
    		//panel4.setLayout(new GridLayout(2,1));
    		//panel5.add(okButton);
    		//panel5.add(cancel);
    		//con.add(panel1);
    		//con.add(panel2);
    		//con.add(panel3);
    		//con.add(panel4);
    		//con.add(panel5);
    		panel2.add(fontText);
    		panel2.add(styleText);
    		panel2.add(sizeText);
    		panel2.add(okButton);
    		panel3.add(new JScrollPane(fontList));//JList不支持直接滚动，所以要让JList作为JScrollPane的视口视图
    		panel3.add(new JScrollPane(styleList));
    		panel3.add(new JScrollPane(sizeList));
    		panel3.add(cancel);
    		con.add(panel1);
    		con.add(panel2);
    		con.add(panel3);
    		con.add(samplePanel);
    		fontDialog.setSize(350,340);
    		fontDialog.setLocation(200,200);
    		fontDialog.setResizable(false);
    		fontDialog.setVisible(true);
    	}
    
    	//public void menuPerformed(MenuEvent e)
    	//{ checkMenuItemEnabled();//设置剪切、复制、粘贴、删除等功能的可用性
    	//}
    
    	public void actionPerformed(ActionEvent e)
    	{ 	//新建
    		if(e.getSource()==fileMenu_New)
    		{ 	editArea.requestFocus();
    			String currentValue=editArea.getText();
    			boolean isTextChange=(currentValue.equals(oldValue))?false:true;
    			if(isTextChange)
    			{ 	int saveChoose=JOptionPane.showConfirmDialog(this,"您的文件尚未保存，是否保存？","提示",JOptionPane.YES_NO_CANCEL_OPTION);
    				if(saveChoose==JOptionPane.YES_OPTION)
    				{ 	String str=null;
    					JFileChooser fileChooser=new JFileChooser();
    					fileChooser.setFileSelectionMode(JFileChooser.FILES_ONLY);
    					//fileChooser.setApproveButtonText("确定");
    					fileChooser.setDialogTitle("另存为");
    					int result=fileChooser.showSaveDialog(this);
    					if(result==JFileChooser.CANCEL_OPTION)
    					{ 	statusLabel.setText("您没有选择任何文件");
    						return;
    					}
    					File saveFileName=fileChooser.getSelectedFile();
    					if(saveFileName==null || saveFileName.getName().equals(""))
    					{ 	JOptionPane.showMessageDialog(this,"不合法的文件名","不合法的文件名",JOptionPane.ERROR_MESSAGE);
    					}
    					else 
    					{ 	try
    						{ 	FileWriter fw=new FileWriter(saveFileName);
    							BufferedWriter bfw=new BufferedWriter(fw);
    							bfw.write(editArea.getText(),0,editArea.getText().length());
    							bfw.flush();//刷新该流的缓冲
    							bfw.close();
    							isNewFile=false;
    							currentFile=saveFileName;
    							oldValue=editArea.getText();
    							this.setTitle(saveFileName.getName()+" - 记事本");
    							statusLabel.setText("当前打开文件："+saveFileName.getAbsoluteFile());
    						}
    						catch (IOException ioException)
    						{ 
    						}
    					}
    				}
    				else if(saveChoose==JOptionPane.NO_OPTION)
    				{ 	editArea.replaceRange("",0,editArea.getText().length());
    					statusLabel.setText(" 新建文件");
    					this.setTitle("无标题 - 记事本");
    					isNewFile=true;
    					undo.discardAllEdits();	//撤消所有的"撤消"操作
    					editMenu_Undo.setEnabled(false);
    					oldValue=editArea.getText();
    				}
    				else if(saveChoose==JOptionPane.CANCEL_OPTION)
    				{ 	return;
    				}
    			}
    			else
    			{ 	editArea.replaceRange("",0,editArea.getText().length());
    				statusLabel.setText(" 新建文件");
    				this.setTitle("无标题 - 记事本");
    				isNewFile=true;
    				undo.discardAllEdits();//撤消所有的"撤消"操作
    				editMenu_Undo.setEnabled(false);
    				oldValue=editArea.getText();
    			}
    		}//新建结束
    		//打开
    		else if(e.getSource()==fileMenu_Open)
    		{ 	editArea.requestFocus();
    			String currentValue=editArea.getText();
    			boolean isTextChange=(currentValue.equals(oldValue))?false:true;
    			if(isTextChange)
    			{ 	int saveChoose=JOptionPane.showConfirmDialog(this,"您的文件尚未保存，是否保存？","提示",JOptionPane.YES_NO_CANCEL_OPTION);
    				if(saveChoose==JOptionPane.YES_OPTION)
    				{ 	String str=null;
    					JFileChooser fileChooser=new JFileChooser();
    					fileChooser.setFileSelectionMode(JFileChooser.FILES_ONLY);
    					//fileChooser.setApproveButtonText("确定");
    					fileChooser.setDialogTitle("另存为");
    					int result=fileChooser.showSaveDialog(this);
    					if(result==JFileChooser.CANCEL_OPTION)
    					{ 	statusLabel.setText("您没有选择任何文件");
    						return;
    					}
    					File saveFileName=fileChooser.getSelectedFile();
    					if(saveFileName==null || saveFileName.getName().equals(""))
    					{ 	JOptionPane.showMessageDialog(this,"不合法的文件名","不合法的文件名",JOptionPane.ERROR_MESSAGE);
    					}
    					else 
    					{ 	try
    						{ 	FileWriter fw=new FileWriter(saveFileName);
    							BufferedWriter bfw=new BufferedWriter(fw);
    							bfw.write(editArea.getText(),0,editArea.getText().length());
    							bfw.flush();//刷新该流的缓冲
    							bfw.close();
    							isNewFile=false;
    							currentFile=saveFileName;
    							oldValue=editArea.getText();
    							this.setTitle(saveFileName.getName()+" - 记事本");
    							statusLabel.setText("当前打开文件："+saveFileName.getAbsoluteFile());
    						}
    						catch (IOException ioException)
    						{ 
    						}
    					}
    				}
    				else if(saveChoose==JOptionPane.NO_OPTION)
    				{ 	String str=null;
    					JFileChooser fileChooser=new JFileChooser();
    					fileChooser.setFileSelectionMode(JFileChooser.FILES_ONLY);
    					//fileChooser.setApproveButtonText("确定");
    					fileChooser.setDialogTitle("打开文件");
    					int result=fileChooser.showOpenDialog(this);
    					if(result==JFileChooser.CANCEL_OPTION)
    					{ 	statusLabel.setText("您没有选择任何文件");
    						return;
    					}
    					File fileName=fileChooser.getSelectedFile();
    					if(fileName==null || fileName.getName().equals(""))
    					{ 	JOptionPane.showMessageDialog(this,"不合法的文件名","不合法的文件名",JOptionPane.ERROR_MESSAGE);
    					}
    					else
    					{ 	try
    						{ 	FileReader fr=new FileReader(fileName);
    							BufferedReader bfr=new BufferedReader(fr);
    							editArea.setText("");
    							while((str=bfr.readLine())!=null)
    							{ 	editArea.append(str);
    							}
    							this.setTitle(fileName.getName()+" - 记事本");
    							statusLabel.setText(" 当前打开文件："+fileName.getAbsoluteFile());
    							fr.close();
    							isNewFile=false;
    							currentFile=fileName;
    							oldValue=editArea.getText();
    						}
    						catch (IOException ioException)
    						{ 
    						}
    					}
    				}
    				else
    				{ 	return;
    				}
    			}
    			else
    			{ 	String str=null;
    				JFileChooser fileChooser=new JFileChooser();
    				fileChooser.setFileSelectionMode(JFileChooser.FILES_ONLY);
    				//fileChooser.setApproveButtonText("确定");
    				fileChooser.setDialogTitle("打开文件");
    				int result=fileChooser.showOpenDialog(this);
    				if(result==JFileChooser.CANCEL_OPTION)
    				{ 	statusLabel.setText(" 您没有选择任何文件 ");
    					return;
    				}
    				File fileName=fileChooser.getSelectedFile();
    				if(fileName==null || fileName.getName().equals(""))
    				{ 	JOptionPane.showMessageDialog(this,"不合法的文件名","不合法的文件名",JOptionPane.ERROR_MESSAGE);
    				}
    				else
    				{ 	try
    					{ 	FileReader fr=new FileReader(fileName);
    						BufferedReader bfr=new BufferedReader(fr);
    						editArea.setText("");
    						while((str=bfr.readLine())!=null)
    						{ 	editArea.append(str);
    						}
    						this.setTitle(fileName.getName()+" - 记事本");
    						statusLabel.setText(" 当前打开文件："+fileName.getAbsoluteFile());
    						fr.close();
    						isNewFile=false;
    						currentFile=fileName;
    						oldValue=editArea.getText();
    					}
    					catch (IOException ioException)
    					{ 
    					}
    				}
    			}
    		}//打开结束
    		//保存
    		else if(e.getSource()==fileMenu_Save)
    		{ 	editArea.requestFocus();
    			if(isNewFile)
    			{ 	String str=null;
    				JFileChooser fileChooser=new JFileChooser();
    				fileChooser.setFileSelectionMode(JFileChooser.FILES_ONLY);
    				//fileChooser.setApproveButtonText("确定");
    				fileChooser.setDialogTitle("保存");
    				int result=fileChooser.showSaveDialog(this);
    				if(result==JFileChooser.CANCEL_OPTION)
    				{ 	statusLabel.setText("您没有选择任何文件");
    					return;
    				}
    				File saveFileName=fileChooser.getSelectedFile();
    				if(saveFileName==null || saveFileName.getName().equals(""))
    				{ 	JOptionPane.showMessageDialog(this,"不合法的文件名","不合法的文件名",JOptionPane.ERROR_MESSAGE);
    				}
    				else 
    				{ 	try
    					{ 	FileWriter fw=new FileWriter(saveFileName);
    						BufferedWriter bfw=new BufferedWriter(fw);
    						bfw.write(editArea.getText(),0,editArea.getText().length());
    						bfw.flush();//刷新该流的缓冲
    						bfw.close();
    						isNewFile=false;
    						currentFile=saveFileName;
    						oldValue=editArea.getText();
    						this.setTitle(saveFileName.getName()+" - 记事本");
    						statusLabel.setText("当前打开文件："+saveFileName.getAbsoluteFile());
    					}
    					catch (IOException ioException)
    					{ 
    					}
    				}
    			}
    			else
    			{ 	try
    				{ 	FileWriter fw=new FileWriter(currentFile);
    					BufferedWriter bfw=new BufferedWriter(fw);
    					bfw.write(editArea.getText(),0,editArea.getText().length());
    					bfw.flush();
    					fw.close();
    				}							
    				catch(IOException ioException)
    				{ 					
    				}
    			}
    		}//保存结束
    		//另存为
    		else if(e.getSource()==fileMenu_SaveAs)
    		{ 	editArea.requestFocus();
    			String str=null;
    			JFileChooser fileChooser=new JFileChooser();
    			fileChooser.setFileSelectionMode(JFileChooser.FILES_ONLY);
    			//fileChooser.setApproveButtonText("确定");
    			fileChooser.setDialogTitle("另存为");
    			int result=fileChooser.showSaveDialog(this);
    			if(result==JFileChooser.CANCEL_OPTION)
    			{ 	statusLabel.setText("　您没有选择任何文件");
    				return;
    			}				
    			File saveFileName=fileChooser.getSelectedFile();
    			if(saveFileName==null||saveFileName.getName().equals(""))
    			{ 	JOptionPane.showMessageDialog(this,"不合法的文件名","不合法的文件名",JOptionPane.ERROR_MESSAGE);
    			}	
    			else 
    			{ 	try
    				{ 	FileWriter fw=new FileWriter(saveFileName);
    					BufferedWriter bfw=new BufferedWriter(fw);
    					bfw.write(editArea.getText(),0,editArea.getText().length());
    					bfw.flush();
    					fw.close();
    					oldValue=editArea.getText();
    					this.setTitle(saveFileName.getName()+" - 记事本");
    					statusLabel.setText("　当前打开文件:"+saveFileName.getAbsoluteFile());
    				}						
    				catch(IOException ioException)
    				{ 					
    				}				
    			}
    		}//另存为结束
    		//页面设置
    		else if(e.getSource()==fileMenu_PageSetUp)
    		{ 	editArea.requestFocus();
    			JOptionPane.showMessageDialog(this,"对不起，此功能尚未实现！","提示",JOptionPane.WARNING_MESSAGE);
    		}//页面设置结束
    		//打印
    		else if(e.getSource()==fileMenu_Print)
    		{ 	editArea.requestFocus();
    			JOptionPane.showMessageDialog(this,"对不起，此功能尚未实现！","提示",JOptionPane.WARNING_MESSAGE);
    		}//打印结束
    		//退出
    		else if(e.getSource()==fileMenu_Exit)
    		{ 	int exitChoose=JOptionPane.showConfirmDialog(this,"确定要退出吗?","退出提示",JOptionPane.OK_CANCEL_OPTION);
    			if(exitChoose==JOptionPane.OK_OPTION)
    			{ 	System.exit(0);
    			}
    			else
    			{ 	return;
    			}
    		}//退出结束
    		//编辑
    		//else if(e.getSource()==editMenu)
    		//{ checkMenuItemEnabled();//设置剪切、复制、粘贴、删除等功能的可用性
    		//}
    		//编辑结束
    		//撤销
    		else if(e.getSource()==editMenu_Undo || e.getSource()==popupMenu_Undo)
    		{ 	editArea.requestFocus();
    			if(undo.canUndo())
    			{ 	try
    				{ 	undo.undo();
    				}
    				catch (CannotUndoException ex)
    				{ 	System.out.println("Unable to undo:" + ex);
    					//ex.printStackTrace();
    				}
    			}
    			if(!undo.canUndo())
    				{ 	editMenu_Undo.setEnabled(false);
    				}
    		}//撤销结束
    		//剪切
    		else if(e.getSource()==editMenu_Cut || e.getSource()==popupMenu_Cut)
    		{ 	editArea.requestFocus();
    			String text=editArea.getSelectedText();
    			StringSelection selection=new StringSelection(text);
    			clipBoard.setContents(selection,null);
    			editArea.replaceRange("",editArea.getSelectionStart(),editArea.getSelectionEnd());
    			checkMenuItemEnabled();//设置剪切，复制，粘帖，删除功能的可用性
    		}//剪切结束
    		//复制
    		else if(e.getSource()==editMenu_Copy || e.getSource()==popupMenu_Copy)
    		{ 	editArea.requestFocus();
    			String text=editArea.getSelectedText();
    			StringSelection selection=new StringSelection(text);
    			clipBoard.setContents(selection,null);
    			checkMenuItemEnabled();//设置剪切，复制，粘帖，删除功能的可用性
    		}//复制结束
    		//粘帖
    		else if(e.getSource()==editMenu_Paste || e.getSource()==popupMenu_Paste)
    		{ 	editArea.requestFocus();
    			Transferable contents=clipBoard.getContents(this);
    			if(contents==null)return;
    			String text="";
    			try
    			{ 	text=(String)contents.getTransferData(DataFlavor.stringFlavor);
    			}
    			catch (Exception exception)
    			{ 
    			}
    			editArea.replaceRange(text,editArea.getSelectionStart(),editArea.getSelectionEnd());
    			checkMenuItemEnabled();
    		}//粘帖结束
    		//删除
    		else if(e.getSource()==editMenu_Delete || e.getSource()==popupMenu_Delete)
    		{ 	editArea.requestFocus();
    			editArea.replaceRange("",editArea.getSelectionStart(),editArea.getSelectionEnd());
    			checkMenuItemEnabled();	//设置剪切、复制、粘贴、删除等功能的可用性 
    		}//删除结束
    		//查找
    		else if(e.getSource()==editMenu_Find)
    		{ 	editArea.requestFocus();
    			find();
    		}//查找结束
    		//查找下一个
    		else if(e.getSource()==editMenu_FindNext)
    		{ 	editArea.requestFocus();
    			find();
    		}//查找下一个结束
    		//替换
    		else if(e.getSource()==editMenu_Replace)
    		{ 	editArea.requestFocus();
    			replace();
    		}//替换结束
    		//转到
    		else if(e.getSource()==editMenu_GoTo)
    		{ 	editArea.requestFocus();
    			JOptionPane.showMessageDialog(this,"对不起，此功能尚未实现！","提示",JOptionPane.WARNING_MESSAGE);
    		}//转到结束
    		//时间日期
    		else if(e.getSource()==editMenu_TimeDate)
    		{ 	editArea.requestFocus();
    			//SimpleDateFormat currentDateTime=new SimpleDateFormat("HH:mmyyyy-MM-dd");
    			//editArea.insert(currentDateTime.format(new Date()),editArea.getCaretPosition());
    			Calendar rightNow=Calendar.getInstance();
    			Date date=rightNow.getTime();
    			editArea.insert(date.toString(),editArea.getCaretPosition());
    		}//时间日期结束
    		//全选
    		else if(e.getSource()==editMenu_SelectAll || e.getSource()==popupMenu_SelectAll)
    		{ 	editArea.selectAll();
    		}//全选结束
    		//自动换行(已在前面设置)
    		else if(e.getSource()==formatMenu_LineWrap)
    		{ 	if(formatMenu_LineWrap.getState())
    				editArea.setLineWrap(true);
    			else 
    				editArea.setLineWrap(false);
    
    		}//自动换行结束
    		//字体设置
    		else if(e.getSource()==formatMenu_Font)
    		{ 	editArea.requestFocus();
    			font();
    		}//字体设置结束
    		//设置状态栏可见性
    		else if(e.getSource()==viewMenu_Status)
    		{ 	if(viewMenu_Status.getState())
    				statusLabel.setVisible(true);
    			else 
    				statusLabel.setVisible(false);
    		}//设置状态栏可见性结束
    		//帮助主题
    		else if(e.getSource()==helpMenu_HelpTopics)
    		{ 	editArea.requestFocus();
    			JOptionPane.showMessageDialog(this,"路漫漫其修远兮，吾将上下而求索。","帮助主题",JOptionPane.INFORMATION_MESSAGE);
    		}//帮助主题结束
    		//关于
    		else if(e.getSource()==helpMenu_AboutNotepad)
    		{ 	editArea.requestFocus();
    			JOptionPane.showMessageDialog(this,
    				"&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&\n"+
    				" 编写者：黄山学院信息工程学院计算机科学与技术专业06级本科 张选仲 \n"+
    				" 编写时间：大二下暑假期间 \n"+
    				" 本人QQ：414644665 \n"+
    				" e-mail：zxz414644665@163.com \n"+
    				" 初学者，一些地方借鉴他人，不足之处希望大家能提出意见，谢谢！ \n"+
    				"&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&\n",
    				"记事本",JOptionPane.INFORMATION_MESSAGE);
    		}//关于结束
    	}//方法actionPerformed()结束
    
    	//实现DocumentListener接口中的方法(与撤销操作有关)
    	public void removeUpdate(DocumentEvent e)
    	{ 	editMenu_Undo.setEnabled(true);
    	}
    	public void insertUpdate(DocumentEvent e)
    	{ 	editMenu_Undo.setEnabled(true);
    	}
    	public void changedUpdate(DocumentEvent e)
    	{ 	editMenu_Undo.setEnabled(true);
    	}//DocumentListener结束
    
    	//实现接口UndoableEditListener的类UndoHandler(与撤销操作有关)
    	class UndoHandler implements UndoableEditListener
    	{ 	public void undoableEditHappened(UndoableEditEvent uee)
    		{ 	undo.addEdit(uee.getEdit());
    		}
    	}
    
    	//main函数开始
    	public static void main(String args[])
    	{ 	Notepad notepad=new Notepad();
    		notepad.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);//使用 System exit 方法退出应用程序
    	}//main函数结束
    }

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