java语言写一个文本编辑器的源代码

import java.awt.*;
import javax.swing.*;
import java.awt.event.*;
import javax.swing.event.*;
import java.util.*; //Date needed
import java.io.PrintWriter;
public class NotePad extends JFrame
{
JTextArea jta;
class newl implements ActionListener
{
public void actionPerformed(ActionEvent e)
{
jta.setText("");
}
}

class openl implements ActionListener
{ public void actionPerformed(ActionEvent e)
{
JFileChooser jf=new JFileChooser();
jf.showOpenDialog(NotePad.this);

}

}
//保存文件的监听
class savel implements ActionListener
{
public void actionPerformed(ActionEvent e)
{
JFileChooser jf = new JFileChooser();
jf.showSaveDialog(NotePad.this);

}
}
//打印的监听 ?
class printl implements ActionListener
{
public void actionPerformed(ActionEvent e)
{
// PrintWriter p = new PrintWriter(NotePad.this);
}
}
//退出记事本的监听
class exitl implements ActionListener
{
public void actionPerformed(ActionEvent e)
{
System.exit(0);//退出
}
}

//拷贝的监听
class copyl implements ActionListener
{
public void actionPerformed(ActionEvent e)
{
jta.copy();
}
}

//粘贴的监听
class pastel implements ActionListener
{
public void actionPerformed(ActionEvent e)
{
jta.paste();
}
}
//剪切的监听
class cutl implements ActionListener
{
public void actionPerformed(ActionEvent e)
{
jta.cut();
}
}
//查找的监听

//添加日期的监听
class datel implements ActionListener
{
public void actionPerformed(ActionEvent e)
{
Date d=new Date();
jta.append(d.toString());
}
}

//构造函数
public NotePad()
{
jta=new JTextArea("",24,40);
JScrollPane jsp=new JScrollPane(jta);
JMenuBar jmb=new JMenuBar();
JMenu mFile=new JMenu("File");
JMenu mEdit=new JMenu("Edit");

JMenuItem mNew=new JMenuItem("New",KeyEvent.VK_N);
mNew.addActionListener(new newl());
mFile.add(mNew);

JMenuItem mOpen=new JMenuItem("Open",KeyEvent.VK_O);
mOpen.addActionListener(new openl());
mFile.add(mOpen);

JMenuItem mSave=new JMenuItem("Save");
mSave.addActionListener(new savel());
mFile.add(mSave);

mFile.addSeparator(); //添加分割线

JMenuItem mPrint = new JMenuItem("Print");
mPrint.addActionListener(new printl());
mFile.add(mPrint);

mFile.addSeparator(); //添加分割线

JMenuItem mExit=new JMenuItem("Exit");
mExit.addActionListener(new exitl());
mFile.add(mExit);
mFile.setMnemonic(KeyEvent.VK_F);

//编辑菜单的子菜单的处理
JMenuItem jmi;
jmi=new JMenuItem("Copy");
jmi.addActionListener(new copyl());
mEdit.add(jmi);

jmi=new JMenuItem("Cut");
jmi.addActionListener(new cutl());
mEdit.add(jmi);

jmi=new JMenuItem("Paste");
jmi.addActionListener(new pastel());
mEdit.add(jmi);

mEdit.addSeparator(); //添加分割线

jmi=new JMenuItem("Find");

mEdit.add(jmi);

jmi=new JMenuItem("FindNext");
mEdit.add(jmi);
mEdit.addSeparator();
jmi=new JMenuItem("Select All");
mEdit.add(jmi);
jmi=new JMenuItem("Date/Time");
jmi.addActionListener(new datel());
mEdit.add(jmi);

jmb.add(mFile);
jmb.add(mEdit);

this.setJMenuBar(jmb);

this.getContentPane().add(jsp);
this.setSize(200,200);
this.setVisible(true);
}
//主函数，程序入口点
public static void main(String s[])
{
new NotePad();
}

}

一个小的文本编辑器：
import java.awt.event.ActionListener;
import java.util.EventListener;
import java.awt.event.*;
import java.awt.*;
import java.io.*;
import java.lang.*;
import java.awt.datatransfer.*;
import javax.swing.*;

public class MiniEdit extends JFrame implements ActionListener {

/**
* Method main
*
*
* @param args
*
*/
MenuBar menuBar = new MenuBar();
Menu file = new Menu("File"),
edit = new Menu("Edit"),
help = new Menu("Help");

MenuItem[] menuItem ={
new MenuItem("New"),
new MenuItem("Open"),
new MenuItem("Save"),
new MenuItem("Exit"),
new MenuItem("Select All"),
new MenuItem("Copy"),
new MenuItem("Cut"),
new MenuItem("Paste"),
new MenuItem("Help")
};

TextArea textArea = new TextArea();
String fileName = "NoName";
Toolkit toolKit = Toolkit.getDefaultToolkit();
Clipboard clipboard = toolKit.getSystemClipboard();

//opne and close message dialogs
private FileDialog openFileDialog =
new FileDialog(this,"Open File",FileDialog.LOAD);
private FileDialog saveFileDialog =
new FileDialog(this,"Save File",FileDialog.SAVE);

public static void main(String[] args) {
// TODO: Add your code here
MiniEdit MyEdit = new MiniEdit();
MyEdit.show();
}

/**
* Method MiniEdit
*
*
*/
public MiniEdit() {
// TODO: Add your code here
setTitle("MiniEdit");
setFont(new Font("Times New Roman",Font.PLAIN,15));
setBackground(Color.blue);
setSize(500,500);

setMenuBar(menuBar);
menuBar.add(file);
menuBar.add(edit);
menuBar.add(help);
for(int i=0;i<4;i++)
{
file.add(menuItem[i]);
edit.add(menuItem[i+4]);
}
help.add(menuItem[8]);
add(textArea);

addWindowListener(new WindowAdapter(){//关闭窗口的事件监听
public void windowClosing(WindowEvent e){
e.getWindow().dispose();
System.exit(0);
}
});

//add actionListener
for(int i=0;i {
menuItem[i].addActionListener(this);
}

}

/**
* Method actionPerformed
*
*
* @param e
*
*/
public void actionPerformed(ActionEvent e) {
// TODO: Add your code here
Object eventSource = e.getSource();

if(eventSource == menuItem[0])//newItem
{
textArea.setText("");
}

else if(eventSource == menuItem[1])//OpenItem
{
openFileDialog.show();
fileName = openFileDialog.getDirectory()+openFileDialog.getFile();
if(fileName != null)
{
openFile(fileName);
}
}

else if(eventSource ==menuItem[2])//SaveItem
{
saveFileDialog.show();
fileName = saveFileDialog.getDirectory()+saveFileDialog.getFile();
if(fileName !=null)
{
writeFile(fileName);
}
}

else if(eventSource==menuItem[3])//exitItem
{
System.exit(0);
}

else if(eventSource == menuItem[4])//Select All
{
textArea.selectAll();
}
else if(eventSource == menuItem[5])//copy
{
String text = textArea.getSelectedText();
StringSelection selection= new StringSelection(text);

clipboard.setContents(selection,null);

}

else if(eventSource == menuItem[6])//cut
{
String text = textArea.getSelectedText();
StringSelection selection = new StringSelection(text);

clipboard.setContents(selection,null);
textArea.replaceText("",textArea.getSelectionStart(),
textArea.getSelectionEnd());
}

else if(eventSource == menuItem[7])//Paste
{
Transferable contents = clipboard.getContents(this);
if(contents==null)
return;
String text;
text="";
try{
text = (String)contents.getTransferData(DataFlavor.stringFlavor);

}catch(Exception ex){}
textArea.replaceText(text,
textArea.getSelectionStart(),textArea.getSelectionEnd());
}
else if(eventSource == menuItem[8])
{
// JOptionPane.showMessageDialog(null,"This is a MiniEdit.");
}

}

//Read file
public void openFile(String fileName){
try{
File file = new File(fileName);
FileReader readIn = new FileReader(file);
int size = (int)file.length();
int charsRead = 0;
char[] content = new char[size];
while(readIn.ready())
charsRead += readIn.read(content,charsRead,size-charsRead);
readIn.close();
textArea.setText(new String(content,0,charsRead));
}catch(Exception e)
{
System.out.println("Error opening file!");
}
}

//write file
public void writeFile(String fileName){
try{
File file = new File(fileName);
FileWriter write = new FileWriter(file);
write.write(textArea.getText());
write.close();
}catch(Exception e){
System.out.println("Error closing file!");
}
}

}