Java实现记事本

import java.awt.Color;
import java.awt.FileDialog;
import java.awt.Frame;
import java.awt.Menu;
import java.awt.MenuBar;
import java.awt.MenuItem;
import java.awt.TextArea;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.event.WindowAdapter;
import java.awt.event.WindowEvent;
import java.io.DataOutputStream;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.IOException;


public class MyFrame{
	
	public static void main(String []args)
	{
		final Frame f=new Frame("zhycheng");
		f.setSize(300, 400);
		f.setLocation(400, 300);
		f.setBackground(Color.CYAN);
		//TextField tf=new TextField(20);
		//f.add(tf,"North");
		final TextArea ta=new TextArea();
		f.add(ta);
		f.setVisible(true);
		f.addWindowListener(new WindowAdapter()
		{

			@Override
			public void windowClosing(WindowEvent e) {
				// TODO Auto-generated method stub
				super.windowClosing(e);
				System.exit(0);
			}
			
		});
		
		MenuBar mb=new MenuBar();
		Menu m1=new Menu("File");
		Menu m2=new Menu("Edit");
		//MenuItem mi1=new MenuItem("New");
		MenuItem mi2=new MenuItem("Open");
		mi2.addActionListener(new ActionListener(){

			@Override
			public void actionPerformed(ActionEvent e) {
				// TODO Auto-generated method stub
				FileDialog fd=new FileDialog(f,"zhycheng",FileDialog.LOAD);
				fd.show();
				String strFile=fd.getDirectory()+fd.getFile();
				FileInputStream fis=null;
				if(strFile!=null)
				{
					try {
						fis=new FileInputStream(strFile);
						byte []buf=new byte[10*1024];
						int len=fis.read(buf);
						ta.append(new String(buf,0,len));
						
						
					} catch (Exception e1) {
						// TODO Auto-generated catch block
						e1.printStackTrace();
					}
					finally
					{
						try {
							fis.close();
						} catch (IOException e1) {
							// TODO Auto-generated catch block
							e1.printStackTrace();
						}
					}
				}
				
			}});
		MenuItem mi3=new MenuItem("Save");
		mi3.addActionListener(new ActionListener(){

			@Override
			public void actionPerformed(ActionEvent e) {
				// TODO Auto-generated method stub
				
				FileDialog fd=new FileDialog(f,"zhycheng",FileDialog.SAVE);
				fd.show();
				String path=fd.getDirectory()+fd.getFile()+".txt";
				FileOutputStream fos=null;
				DataOutputStream dos=null;
				try {
					fos=new FileOutputStream(path);
					String sa=ta.getText();
					dos=new DataOutputStream(fos);
					dos.writeUTF(sa);
					
					
					
					
					
				} catch (Exception e1) {
					
					e1.printStackTrace();
				}
				finally
				{
					try {
						dos.close();
					} catch (IOException e1) {
						// TODO Auto-generated catch block
						e1.printStackTrace();
					}
				}
				
				
				
			}});
		MenuItem mi4=new MenuItem("Exit");
		mi4.addActionListener(new ActionListener(){

			@Override
			public void actionPerformed(ActionEvent e) {
				// TODO Auto-generated method stub
				System.exit(0);
				
			}});
		MenuItem mi5=new MenuItem("Copy");
		MenuItem mi6=new MenuItem("Paste");
			//m1.add(mi1);
			m1.add(mi2);
			m1.add(mi3);
			m1.add(mi4);
			m2.add(mi5);
			m2.add(mi6);
			mb.add(m1);
			mb.add(m2);
			f.setMenuBar(mb);
		
		
		
	}
	
}

这段代码只是实现了记事本的简单功能，主要有打开文件，保存文件，退出功能。没有必要实现全部功能，因为做PC上的应用软件不是Java的强项。