简易的记事本，简易记事本,import java.

简易的记事本，简易记事本,import java.

import java.awt.BorderLayout;import java.awt.event.ActionEvent;import java.awt.event.ActionListener;import java.io.*;import javax.swing.JFileChooser;import javax.swing.JFrame;import javax.swing.JMenu;import javax.swing.JMenuBar;import javax.swing.JMenuItem;import javax.swing.JScrollPane;import javax.swing.JTextArea;public class Notebook extends JFrame{    JTextArea jta=null;    JScrollPane jsp=null;    JMenuBar jbr=null;    JMenu jm1,jm2;    JMenuItem jmi2,jmi3,jmi4;    public static void main(String[] args) {        Notebook nb=new Notebook();    }    public Notebook()    {        jta=new JTextArea();        jsp=new JScrollPane(jta);        jmi2=new JMenuItem("打开");        jmi2.setActionCommand("打开");        jmi2.addActionListener(new Mylistener());        jmi3=new JMenuItem("保存");        jmi3.setActionCommand("保存");        jmi3.addActionListener(new Mylistener());        jmi4=new JMenuItem("查看帮助");        jmi4.setActionCommand("查看帮助");        jmi4.addActionListener(new Mylistener());        jm1=new JMenu("选项");        jm1.add(jmi2);        jm1.add(jmi3);        jm2=new JMenu("帮助");        jm2.add(jmi4);        jbr=new JMenuBar();        jbr.add(jm1);        jbr.add(jm2);        this.add(jsp);        this.add(jbr,BorderLayout.NORTH);        this.setTitle("记事本");        this.setSize(600,500);        this.setLocation(200,200);        this.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);        this.setVisible(true);    }    class Mylistener implements ActionListener    {        InputStreamReader isr=null;        BufferedReader bfd=null;        BufferedWriter bfw=null;        JFileChooser jfc=null;        FileReader fd=null;        File creatfile=null;        FileWriter fw=null;        public void actionPerformed(ActionEvent arg0) {                if(arg0.getActionCommand().equals("打开")){                jfc=new JFileChooser();                jfc.setDialogTitle("请选择要打开的文件");                jfc.showOpenDialog(null);                jfc.setVisible(true);                String filename=jfc.getSelectedFile().getAbsolutePath();                try {                    fd=new FileReader(filename);                    bfd=new BufferedReader(fd);                    String s="",allstring="";                    while((s=bfd.readLine())!=null){                        allstring+=s+"\\n";                    }                    jta.setText(allstring);                } catch (Exception e) {                    e.printStackTrace();                }finally{                    try {                        fd.close();                        bfd.close();                    } catch (IOException e) {                        e.printStackTrace();                    }                }            }else if(arg0.getActionCommand().equals("保存")){                //很重要的一个组件JFileChooser                jfc=new JFileChooser();                jfc.setDialogTitle("请选择要保存的路径");                jfc.showSaveDialog(null);                jfc.setVisible(true);                String savepath=jfc.getSelectedFile().getAbsolutePath();                try {                    fw=new FileWriter(savepath);                    bfw=new BufferedWriter(fw);                    String newfile=jta.getText();                    bfw.write(newfile);                } catch (Exception e) {                    e.printStackTrace();                }finally{                    try {                        bfw.close();                        fw.close();                    } catch (IOException e) {                        e.printStackTrace();                    }                }            }       }    }}//该片段来自于http://byrx.net