package main1;

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


public class Test implements ActionListener {
         JFrame frame;
         JMenuBar bar;
         JMenu fileMenu,editMenu;
         JMenuItem newItem,openItem,saveItem,savesItem,closeItem;
         ImageIcon newIcon,openIcon,saveIcon,savesIcon,closeIcon;
         JScrollPane scroll;
         JTextArea area;
         JFileChooser chooser;
         File file;


     public Test(){
             frame =new JFrame("记事本");
             bar =new JMenuBar();
             fileMenu =new JMenu("文件");
             editMenu =new JMenu("编辑");
             newIcon=new ImageIcon("d:"+File.separator+"java"+File.separator+"1.png");
             openIcon=new ImageIcon("d:"+File.separator+"java"+File.separator+"2.png");
             saveIcon=new ImageIcon("d:"+File.separator+"java"+File.separator+"3.png");
             savesIcon=new ImageIcon("d:"+File.separator+"java"+File.separator+"3.png");
             closeIcon=new ImageIcon("d:"+File.separator+"java"+File.separator+"4.png");
             newItem=new JMenuItem("新建(N)",newIcon);
             openItem=new JMenuItem("打开(O)",openIcon);
             saveItem=new JMenuItem("保存(A)",saveIcon);
             savesItem = new JMenuItem("另存为(B)",savesIcon);
             closeItem=new JMenuItem("关闭(X)",closeIcon);
             area =new JTextArea();
             scroll=new JScrollPane(area);

             newItem.setMnemonic(KeyEvent.VK_N);
             openItem.setMnemonic(KeyEvent.VK_O);
             saveItem.setMnemonic(KeyEvent.VK_A);
             savesItem.setMnemonic(KeyEvent.VK_B);
             closeItem.setMnemonic(KeyEvent.VK_X);

             newItem.setAccelerator(KeyStroke.getKeyStroke(KeyEvent.VK_N,InputEvent.CTRL_DOWN_MASK));
             openItem.setAccelerator(KeyStroke.getKeyStroke(KeyEvent.VK_O,InputEvent.CTRL_DOWN_MASK));
             saveItem.setAccelerator(KeyStroke.getKeyStroke(KeyEvent.VK_A,InputEvent.CTRL_DOWN_MASK));
             savesItem.setAccelerator(KeyStroke.getKeyStroke(KeyEvent.VK_B,InputEvent.CTRL_DOWN_MASK));
             closeItem.setAccelerator(KeyStroke.getKeyStroke(KeyEvent.VK_X,InputEvent.CTRL_DOWN_MASK));

             fileMenu.add(newItem);
             fileMenu.add(openItem);
             fileMenu.add(saveItem);
             fileMenu.add(savesItem);
             fileMenu.add(closeItem);
             
             JScrollPane scroll =new  JScrollPane(area, JScrollPane.VERTICAL_SCROLLBAR_ALWAYS, JScrollPane.HORIZONTAL_SCROLLBAR_AS_NEEDED);//加滚动条
             newItem.addActionListener(this);
             openItem.addActionListener(this);
             saveItem.addActionListener(this);
             savesItem.addActionListener(this);
             closeItem.addActionListener(this);

             bar.add(fileMenu);
             bar.add(editMenu);

             frame.addWindowListener(new WindowAdapter() {
               public void windowClosing(WindowEvent arg0){
                   System.exit(1);
               }});
              frame.setJMenuBar(bar);
              frame.add(scroll);
              frame.setVisible(true);
              frame.setSize(800,600);
              frame.setLocation(500,400);
         }
         
         public void actionPerformed(ActionEvent a) {        
             Object obj= a.getSource();
             if(obj instanceof JMenuItem) {
                 JMenuItem item=(JMenuItem) obj;
                 if(item==newItem) {       //新建
                     new Test();
                 }
                 else if(item==openItem) {            //打开
                     chooser=new JFileChooser();
                     chooser.showOpenDialog(null);
                     file=chooser.getSelectedFile();
                     try {
                         FileInputStream fis=new FileInputStream(file);
                         byte[] b=new byte[fis.available()];
                         fis.read(b);
                         area.append(new String(b));
                         fis.close();
                     }catch(FileNotFoundException e) {
                         e.printStackTrace();
                     }catch(IOException e) {
                         e.printStackTrace();
                     }
                 }
                 else if(item==saveItem) {             //保存
                     if(file!=null) {
                         try {
                             PrintStream out = new PrintStream(new FileOutputStream(file));
                             out.print(this.area.getText());
                             out.close();
                         } catch (FileNotFoundException e){
                             e.printStackTrace();
                         }
                     }
                     else if(item==savesItem){              //另存为
                     chooser.showOpenDialog(null);
                     file=chooser.getSelectedFile();
                     try {
                         if(!file.exists()) {
                             file.createNewFile();
                     }
                     FileOutputStream fos=new FileOutputStream(file);
                     byte[] b=area.getText().getBytes();
                     fos.write(b);
                     fos.close();
                     }
                     catch(IOException e) {
                             e.printStackTrace();
                     }   
                 }
                     
                 }else if(item==closeItem){           //关闭
                     System.exit(1);
                 }
                     }
                     
                 }
             }