java實現簡單的記事本

包含開啟檔案，儲存檔案，複製，粘貼，剪下功能，都是在功能表列目上實現的功能

原始碼：

import java.awt.*;import java.awt.event.*;import java.io.*;import javax.swing.*;import javax.swing.event.*;import javax.swing.filechooser.FileFilter;import static java.awt.event.InputEvent.*;import java.awt.datatransfer.*;import java.util.Enumeration;import java.util.Hashtable;/*import javax.swing.*;import javax.swing.filechooser.FileFilter;import java.awt.event.*;import java.awt.*;import java.io.BufferedReader;import java.io.BufferedWriter;import java.io.File;import java.io.FileNotFoundException;import java.io.FileReader;import java.io.FileWriter;import java.io.IOException;*/class jishiben {  public static void main(String args[])  {     TextEdit TE=new TextEdit("記事本");  }}class TextEdit extends Frame implements ActionListener{   MenuBar m;   Menu m1,m2;   MenuItem xinjian,dakai,baocun,tuichu,jianqie,fuzhi,zhantie;   TextArea text;   String filename;   FileDialog openFD,saveFD;   BufferedReader in;   FileReader read;   BufferedWriter out;   FileWriter writer;   Clipboard cb;   TextEdit(String s)   {     super(s);     m=new MenuBar();     m1=new Menu("檔案");     xinjian=new MenuItem("建立");     dakai=new MenuItem("開啟");     baocun=new MenuItem("儲存");     tuichu=new MenuItem("退出");     m2=new Menu("編輯");     jianqie=new MenuItem("剪下");     fuzhi=new MenuItem("複製");     zhantie=new MenuItem("粘貼");     text=new TextArea();     openFD=new FileDialog(this,"開啟",FileDialog.LOAD);     saveFD=new FileDialog(this,"儲存",FileDialog.SAVE);     filename="NoName";          m1.add(xinjian);     m1.addSeparator();     m1.add(dakai);     m1.addSeparator();     m1.add(baocun);     m1.addSeparator();     m1.add(tuichu);     m2.add(jianqie);     m2.addSeparator();     m2.add(fuzhi);     m2.addSeparator();     m2.add(zhantie);     m.add(m1);     m.add(m2);          //關鍵區段，沒有為cb申請記憶體，下面對cb操作會出錯    cb = new Clipboard("nothing");     //          setMenuBar(m);     setSize(300,400);setVisible(true);     add(text,"Center");          xinjian.addActionListener(this);     dakai.addActionListener(this);     baocun.addActionListener(this);     tuichu.addActionListener(this);     jianqie.addActionListener(this);     fuzhi.addActionListener(this);     zhantie.addActionListener(this);     addWindowListener(new WindowAdapter()                      {                        public void windowClosing(WindowEvent e)                        {                          System.exit(0);                        }                      });    }        public void actionPerformed(ActionEvent e)    {      if(e.getSource()==xinjian)       {         text.setText("");       }      if(e.getSource()==dakai)       {        openFD.show();        String s;        filename=openFD.getDirectory()+openFD.getFile();        if(filename!=null)         {          try           {            File file=new File(filename);            read=new FileReader(file);            in=new BufferedReader(read);            while((s=in.readLine())!=null)                text.append(s+'\n');            in.close();            read.close();           }            catch(IOException e2){}         }       }            if(e.getSource()==baocun)      {        saveFD.show();        filename=saveFD.getDirectory()+saveFD.getFile();        if(filename!=null)        {         try           {            File file=new File(filename);            writer=new FileWriter(file);            out=new BufferedWriter(writer);            out.write(text.getText(),0,(text.getText()).length());                        out.close();            writer.close();           }          catch(IOException e2){}         }      }      if(e.getSource()==tuichu)      {        System.exit(0);      }                             if(e.getSource()==jianqie)      {      //類text中沒有cut方法，不能使用text.cut        String s=text.getSelectedText();        StringSelection select=new StringSelection(s);        cb.setContents(select,null);        text.replaceRange("",text.getSelectionStart(),text.getSelectionEnd());      }      if(e.getSource()==fuzhi)      {      //同上，沒有copy這個方法        String s=text.getSelectedText();        StringSelection select=new StringSelection(s);        cb.setContents(select,null);      }      if(e.getSource()==zhantie)      {      //同上，沒有paste方法           String s="";          Transferable t = cb.getContents(null);          try           {                if (t != null                    && t.isDataFlavorSupported(DataFlavor.stringFlavor))                 {                        // 因為原系的剪貼簿裡有多種資訊, 如文字, 圖片, 檔案等                        // 先判斷開始取得的可傳輸的資料是不是文字, 如果是, 取得這些文字                                            s = (String)t.getTransferData(DataFlavor.stringFlavor);                        // 同樣, 因為Transferable中的DataFlavor是多種類型的,                        // 所以傳入DataFlavor這個參數, 指定要取得哪種類型的Data.                        //System.out.println(s);                }          }           catch (UnsupportedFlavorException ex)           {                ex.printStackTrace();          }           catch (IOException ex)           {                ex.printStackTrace();          }                    text.insert(s,text.getCaretPosition());                }          }     }