Object eventSource = e.getSource();
    if(eventSource == newItem){
  public Main(){
       StringSelection selection=new StringSelection(text);
       textArea.selectAll();
    }else if(eventSource == copyItem){
    fileMenu.add(exitItem);

import java.awt.*;
       String text;
   Menu fileMenu = new Menu("File");
    }else if(eventSource == exitItem){
      if(fileName != null)
    }
        writeFile(fileName);

复制代码 代码如下:

   MenuItem openItem = new MenuItem("Open");
                      });
   MenuItem selectItem = new MenuItem("Select All");
    }
   MenuItem pasteItem = new MenuItem("Paste");
        readFile(fileName);
TextArea textArea = new TextArea();
        }
    }
      FileWriter writeOut = new FileWriter(file);
      int charsRead = 0;
    setBackground(Color.white);

       textArea.replaceRange(text,textArea.getSelectionStart(),textArea.getSelectionEnd());
   String fileName = null;
                        }
    saveItem.addActionListener(this);
       Transferable contents=clipBoard.getContents(this);
      textArea.setText(new String(content, 0, charsRead));
   MenuItem newItem = new MenuItem("New");
      if (fileName!= null)
    addWindowListener(new WindowAdapter(){
    fileMenu.add(saveAsItem);
    add(textArea);
       clipBoard.setContents(selection,null);
      writeOut.close();
    @SuppressWarnings("deprecation")
        private static final long serialVersionUID = 1L;
    private FileDialog openFileDialog = new FileDialog(this,"Open File",FileDialog.LOAD);
  public void readFile(String fileName){ //读取文件处理
       clipBoard.setContents(selection,null);
      openFileDialog.show();
            text=(String)contents.getTransferData(DataFlavor.stringFlavor);
import java.awt.datatransfer.*;
    }else if(eventSource == openItem){
    exitItem.addActionListener(this);
    }
   
    setSize(400,300);
  }
      fileName = openFileDialog.getDirectory()+openFileDialog.getFile();
      File file = new File (fileName);
    }else if(eventSource == selectItem){
}

    newItem.addActionListener(this);
      textArea.setText("");
      File file = new File(fileName);
      fileName = saveAsFileDialog.getDirectory()+saveAsFileDialog.getFile();
    try{
    fileMenu.add(openItem);
      System.exit(0);
    catch(IOException e){
    copyItem.addActionListener(this);
 
  public void actionPerformed(ActionEvent e) {  //监听事件
      readIn.close();
    }else if (eventSource == saveItem){
    fileMenu.addSeparator();
  }
  }
        writeFile(fileName);
    }else if(eventSource == pasteItem){
    }else if(eventSource == cutItem){
    fileMenu.add(newItem);
      System.out.println("Error opening file");
   MenuItem cutItem = new MenuItem("Cut");
import java.io.*;
      writeOut.write(textArea.getText());
   MenuItem exitItem = new MenuItem("Exit");
    setTitle("记事本程序-by Jackbase");
    fileMenu.addSeparator();
    selectItem.addActionListener(this);
    setFont(new Font("Times New Roman",Font.PLAIN,12));
import java.awt.event.*;
        }catch(Exception exception){
    catch(IOException e){
    setMenuBar(menuBar);
                      public void windowClosing(WindowEvent e){
      System.out.println("Error writing file");
 
    cutItem.addActionListener(this);
      Frame frame = new Main(); //创建对象
       StringSelection selection=new StringSelection(text);
    openItem.addActionListener(this);
 
    editMenu.add(cutItem);
   Clipboard clipBoard=toolKit.getSystemClipboard();
      while(readIn.ready())
       textArea.replaceRange("",textArea.getSelectionStart(),textArea.getSelectionEnd());
                          System.exit(0);
   MenuItem saveItem = new MenuItem("Save");
   MenuItem copyItem = new MenuItem("Copy");
    editMenu.add(selectItem);
   }
    editMenu.addSeparator();
      int size = (int)file.length();
 
    }else if(eventSource == saveAsItem){
public class Main extends Frame implements ActionListener {
    saveAsItem.addActionListener(this);

完整代码如下：
  public void writeFile(String fileName){  //写入文件处理
   Toolkit toolKit=Toolkit.getDefaultToolkit();
       String text=textArea.getSelectedText();
 
      char[] content = new char[size];
   Menu editMenu = new Menu("Edit");
    private FileDialog saveAsFileDialog = new FileDialog(this,"Save File As",FileDialog.SAVE);
      FileReader readIn = new FileReader(file);
    fileMenu.add(saveItem);
    menuBar.add(fileMenu);
   MenuBar menuBar = new MenuBar();
    }
    pasteItem.addActionListener(this);
 
    menuBar.add(editMenu);
      if(fileName != null)
      frame.show();   //是对象显示
        charsRead += readIn.read(content, charsRead, size - charsRead);
        public static void main(String[] args){
   MenuItem saveAsItem = new MenuItem("Save As");
    editMenu.add(copyItem);
    try{
       if(contents==null) return;
  }

运行结果如下图所示：

       String text=textArea.getSelectedText();
      saveAsFileDialog.show();
       try{
       text="";
    editMenu.add(pasteItem);