如何用JAVA编写简单的记事本程序？

import java.awt.*;

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import java.awt.event.*;

import javax.swing.*;

import javax.swing.event.*;

import java.io.*;

import java.awt.datatransfer.*;public class NewEdit

{

public static void main(String args[])

{

MyFrame EditFrame=new MyFrame();

EditFrame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

EditFrame.setVisible(true);

}

}class MyFrame extends JFrame

{

public MyFrame()

{ Dimension screenSize=toolKit.getScreenSize();

int screenHeight=screenSize.height;

int screenWidth=screenSize.width;

setSize(screenWidth/2,screenHeight/2);

setLocation(screenWidth/4,screenHeight/4);

Image img=toolKit.getImage("icon.gif");

setIconImage(img);

setTitle("MyEdit");

JMenuBar menuBar=new JMenuBar();

setJMenuBar(menuBar);

JMenu fileMenu=new JMenu("文件");

JMenu editMenu=new JMenu("编辑");

JMenu helpMenu=new JMenu("帮助");

menuBar.add(fileMenu);

menuBar.add(editMenu);

menuBar.add(helpMenu);

JMenuItem newItem=new JMenuItem("新建");

newItem.addActionListener(new NewListener());

JMenuItem openItem=new JMenuItem("打开");

openItem.addActionListener(new OpenListener());

JMenuItem saveItem=new JMenuItem("保存");

saveItem.addActionListener(new SaveListener());

JMenuItem escItem=new JMenuItem("退出");

escItem.addActionListener(new

ActionListener()

{

public void actionPerformed(ActionEvent myE)

{

System.exit(0);

}

});

fileMenu.add(newItem);

fileMenu.add(openItem);

fileMenu.add(saveItem);

fileMenu.add(escItem);

JMenuItem allItem=new JMenuItem("全选");

//JMenuItem copyItem=new JMenuItem("复制");

//CopyAction copyAction=new CopyAction();

//copyItem.addActionListener(copyAction);

JMenuItem cutItem=new JMenuItem("剪切");

//JMenuItem pasteItem=new JMenuItem("粘贴");

//Action pasteAction=new PasteAction();

//pasteItem.addActionListener(pasteAction);

editMenu.add(allItem);

allItem.addActionListener(new

ActionListener()

{

public void actionPerformed(ActionEvent myE)

{

textArea.selectAll();

}

});

CopyAction copyAction=new CopyAction("剪切");

editMenu.add(copyAction);

CutAction cutAction=new CutAction("复制");

editMenu.add(cutAction);

Action pasteAction=new PasteAction("粘贴");

editMenu.add(pasteAction);

popup=new JPopupMenu();

popup.add(copyAction);

popup.add(pasteAction);

popup.add(cutAction);

textArea = new JTextArea();

textArea.add(popup);

textArea.addMouseListener(new

MouseListener(){

public void mouseClicked(MouseEvent e) {} public void mouseEntered(MouseEvent e) {} public void mouseExited(MouseEvent e) {} public void mousePressed(MouseEvent e) {

if (e.getButton() == MouseEvent.BUTTON3)

{

popup.show(textArea, e.getX(), e.getY());

}

} public void mouseReleased(MouseEvent e) {} });//可尝试用MouseAdapter,代码可能更简单

JScrollPane scroller = new JScrollPane(textArea);

add(scroller);

//OR--this.getContentPane().add(scroller)

//scroller.setComponentPopupMenu(popup);

//textArea.setInheritsPopupMenu(true);

//scroller.addMouseListener(new MouseAdapter(){});

}

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!");

}

}

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(IOException e)

{

System.out.println("Error opening file!");

}

}

private class NewListener implements ActionListener

{

public void actionPerformed(ActionEvent myE)

{

textArea.setText("");

}

}

private class OpenListener implements ActionListener

{

public void actionPerformed(ActionEvent myE)

{

openFileDialog.setVisible(true);

fileName = openFileDialog.getDirectory()+openFileDialog.getFile();

if(fileName != null)

{

openFile(fileName);

}

}

}

private class SaveListener implements ActionListener

{

public void actionPerformed(ActionEvent myE)

{

saveFileDialog.setVisible(true);

fileName = saveFileDialog.getDirectory()+saveFileDialog.getFile();

if(fileName !=null)

{

writeFile(fileName);

}

}

}

private class CutAction extends AbstractAction

{

public CutAction(String name)

{

super(name);

}

public void actionPerformed(ActionEvent event)

{

String text = textArea.getSelectedText();

StringSelection selection = new StringSelection(text);

clipboard.setContents(selection,null);

textArea.replaceRange("",textArea.getSelectionStart(),

textArea.getSelectionEnd());

}

}

private class CopyAction extends AbstractAction

{

public CopyAction(String name)

{

super(name);

}

public void actionPerformed(ActionEvent event)

{

String text = textArea.getSelectedText();

StringSelection selection= new StringSelection(text);

clipboard.setContents(selection,null);

}

}

private class PasteAction extends AbstractAction

{

public PasteAction(String name)

{

super(name);

}

public void actionPerformed(ActionEvent event)

{

Transferable contents = clipboard.getContents(this);

if(contents==null)

return;

String text;

text="";

try

{

text = (String)contents.getTransferData(DataFlavor.stringFlavor);

}

catch(Exception ex){}

textArea.replaceRange(text,

textArea.getSelectionStart(),textArea.getSelectionEnd());

}

}

private JTextArea textArea;

private JPopupMenu popup;

private String fileName="";

private FileDialog openFileDialog=new FileDialog(this,"OpenFile",FileDialog.LOAD); private FileDialog saveFileDialog=new FileDialog(this,"SaveFile",FileDialog.SAVE);

Toolkit toolKit = Toolkit.getDefaultToolkit();

private Clipboard clipboard = toolKit.getSystemClipboard();}

java记事本源代码

给你个做好了的Java的源程序的记事本，自己看看就行了的，不怎么难的···

import java.awt.*;

import java.awt.event.*;

import java.io.*;

import javax.swing.*;

public class MyNotepad implements ActionListener{

private JFrame frame=new JFrame("新记事本");

private JTextArea jta=new JTextArea();

private String result="";

private boolean flag=true;

private File f;

private JButton jb=new JButton("开始");

private JTextField jtf=new JTextField(15);

private JTextField jt=new JTextField(15);

private JButton jbt=new JButton("替换为");

private JButton jba=new JButton("全部替换");

private Icon ic=new ImageIcon("D:\\java课堂笔记\\GUI\\11.gif");

private String value;

private int start=0;

private JFrame jf=new JFrame("查找");

private JFrame jfc=new JFrame("替换");

@Override

public void actionPerformed(ActionEvent e) {

String comm=e.getActionCommand();

if("新建".equals(comm)){

if(!(frame.getTitle().equals("新记事本"))){

if(!flag){

write();

newNew();

}else{

JFileChooser jfc=new JFileChooser("D:\\java课堂笔记");

int returnVal = jfc.showDialog(null,"保存为");

if(returnVal == JFileChooser.APPROVE_OPTION) {//选择文件后再执行下面的语句，保证了程序的健壮性

f=jfc.getSelectedFile();

flag=false;

write();

}

}

}else if(!(jta.getText().isEmpty())){

JFileChooser jfc=new JFileChooser("D:\\java课堂笔记");

int returnVal = jfc.showDialog(null,"保存为");

if(returnVal == JFileChooser.APPROVE_OPTION) {//选择文件后再执行下面的语句，保证了程序的健壮性

f=jfc.getSelectedFile();

flag=false;

write();

newNew();

}

}else{

newNew();

}

}else if("打开".equals(comm)){

JFileChooser jfc=new JFileChooser("D:\\java课堂笔记");

jfc.setDialogType(JFileChooser.OPEN_DIALOG);

int returnVal = jfc.showOpenDialog(null);

if(returnVal == JFileChooser.APPROVE_OPTION) {//选择文件后再执行下面的语句，保证了程序的健壮性

f=jfc.getSelectedFile();

frame.setTitle(f.getName());

result=read();

flag=false;

value=result;

jta.setText(result);

}

}else if("保存".equals(comm)){

JFileChooser jfc=new JFileChooser("D:\\java课堂笔记");

if(flag){

int returnVal = jfc.showDialog(null,"保存为");

if(returnVal == JFileChooser.APPROVE_OPTION) {//选择文件后再执行下面的语句，保证了程序的健壮性

f=jfc.getSelectedFile();

flag=false;

write();

}

}else{

write();

}

}else if("另存".equals(comm)){

JFileChooser jfc=new JFileChooser("D:\\java课堂笔记");

int returnVal = jfc.showDialog(null,"另存");

if(returnVal == JFileChooser.APPROVE_OPTION) {//选择文件后再执行下面的语句，保证了程序的健壮性

f=jfc.getSelectedFile();

write();

}

}else if("退出".equals(comm)){

System.exit(0);

}else if("撤销".equals(comm)){

jta.setText(value);

}else if("剪切".equals(comm)){

value=jta.getText();

jta.cut();

}else if("复制".equals(comm)){

jta.copy();

}else if("粘贴".equals(comm)){

value=jta.getText();

jta.paste();

}else if("删除".equals(comm)){

value=jta.getText();

jta.replaceSelection(null);

}else if("全选".equals(comm)){

jta.selectAll();

}else if("查找".equals(comm)){

value=jta.getText();

jf.add(jtf,BorderLayout.CENTER);

jf.add(jb,BorderLayout.SOUTH);

jf.setLocation(300,300);

jf.pack();

jf.setVisible(true);

jf.setDefaultCloseOperation(JFrame.DISPOSE_ON_CLOSE);

}else if("替换".equals(comm)){

value=jta.getText();

GridLayout gl=new GridLayout(3,3);

JLabel jl1=new JLabel("查找内容:");

JLabel jl2=new JLabel("替换为:");

jfc.setLayout(gl);

jfc.add(jl1);

jfc.add(jtf);

jfc.add(jb);

jfc.add(jl2);

jfc.add(jt);

jfc.add(jbt);

JLabel jl3=new JLabel();

JLabel jl4=new JLabel();

jfc.add(jl3);

jfc.add(jl4);

jfc.add(jba);

jfc.setLocation(300,300);

jfc.pack();

jfc.setVisible(true);

jfc.setDefaultCloseOperation(JFrame.DISPOSE_ON_CLOSE);

}else if("版本".equals(comm)){

JDialog jd=new JDialog(frame,"关于对话框");

jd.setSize(200,200);

JLabel l=new JLabel("哈哈哈哈哈哈哈哈哈哈呵呵呵呵呵呵呵呵呵呵呵呵呵");

jd.add(l,BorderLayout.CENTER);

jd.setLocation(100,200);

jd.setSize(300,300);

jd.setVisible(true);

// jd.pack();

jd.setDefaultCloseOperation(JDialog.DISPOSE_ON_CLOSE);

}else if("开始".equals(comm)||"下一个".equals(comm)){

String temp=jtf.getText();

int s=value.indexOf(temp,start);

if(value.indexOf(temp,start)!=-1){

jta.setSelectionStart(s);

jta.setSelectionEnd(s+temp.length());

jta.setSelectedTextColor(Color.GREEN);

start=s+1;

jb.setText("下一个");

// value=value.substring(s+temp.length());//不能截取字串

}else {

JOptionPane.showMessageDialog(jf, "查找完毕!", "提示", 0, ic);

jf.dispose();

}

}else if("替换为".equals(comm)){

String temp=jtf.getText();

int s=value.indexOf(temp,start);

if(value.indexOf(temp,start)!=-1){

jta.setSelectionStart(s);

jta.setSelectionEnd(s+temp.length());

jta.setSelectedTextColor(Color.GREEN);

start=s+1;

jta.replaceSelection(jt.getText());

}else {

JOptionPane.showMessageDialog(jf, "查找完毕!", "提示", 0, ic);

jf.dispose();

}

}else if("全部替换".equals(comm)){

String temp=jta.getText();

temp=temp.replaceAll(jtf.getText(), jt.getText());

jta.setText(temp);

}

}

public String read(){

String temp="";

try {

FileInputStream fis = new FileInputStream(f.getAbsolutePath());

byte[] b=new byte[1024];

while(true){

int num=fis.read(b);

if(num==-1)break;

temp=temp+new String(b,0,num);

}

fis.close();

} catch (Exception e1) {

e1.printStackTrace();

}

return temp;

}

public void write(){

try {

FileOutputStream fos=new FileOutputStream(f);

fos.write(jta.getText().getBytes());

fos.close();

} catch (Exception e) {

e.printStackTrace();

}

}

public void newNew(){

frame.dispose();

new MyNotepad();

flag=true;

}

public MyNotepad(){

JMenuBar jmb=new JMenuBar();

String[] menuLab={"文件","编辑","帮助"};

String[][] menuItemLab={{"新建","打开","保存","另存","退出"},

{"撤销","剪切","复制","粘贴","删除","全选","查找","替换"},

{"版本"}};

for(int i=0;imenuLab.length;i++){

JMenu menu=new JMenu(menuLab[i]);

jmb.add(menu);

for(int j=0;jmenuItemLab[i].length;j++){

JMenuItem jmi=new JMenuItem(menuItemLab[i][j]);

menu.add(jmi);

jmi.addActionListener(this);

}

}

frame.setJMenuBar(jmb);

jta.setLineWrap(true);//自动换行

JScrollPane jsp=new JScrollPane(jta);//滚动窗口面板

frame.add(jsp);

jb.addActionListener(this);

jbt.addActionListener(this);

jba.addActionListener(this);

frame.setLocation(200,50);

frame.setSize(620,660);

frame.setVisible(true);

frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

}

public static void main(String[] args) {

new MyNotepad();

}

}

用java编写记事本程序,可以实现新建、打开、保存、退出、复制、粘贴、剪切、全选。

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;

import java.util.Enumeration;

import java.util.Hashtable;

public class MyText extends JFrame implements ActionListener{

private JLabel lb1;

private JMenuBar mb;

private JMenu 文件, 编辑, 格式, 帮助;

private JMenuItem 新建, 打开, 保存, 退出, 复制, 粘贴, 剪切, 全选, 字体, 关于;

private JTextArea editorArea;

private boolean isDirty = false;

private String strFileName = "未命名";

private static final String EDITOR_NAME = "MyText";

public MyText() {

super();

mb = new JMenuBar();

文件 = new JMenu("文件");

编辑 = new JMenu("编辑");

格式 = new JMenu("格式");

帮助 = new JMenu("帮助");

新建 = new JMenuItem("新建");

新建.addActionListener(this);

打开 = new JMenuItem("打开");

打开.addActionListener(this);

保存 = new JMenuItem("保存");

保存.addActionListener(this);

退出 = new JMenuItem("退出");

退出.addActionListener(this);

复制 = new JMenuItem("复制");

复制.addActionListener(this);

粘贴 = new JMenuItem("粘贴");

粘贴.addActionListener(this);

剪切 = new JMenuItem("剪切");

剪切.addActionListener(this);

全选 = new JMenuItem("全选");

全选.addActionListener(this);

字体 = new JMenuItem("字体");

字体.addActionListener(this);

关于 = new JMenuItem("关于");

关于.addActionListener(this);

mb.add(文件);

mb.add(编辑);

mb.add(格式);

mb.add(帮助);

文件.add(新建);

文件.add(打开);

文件.add(保存);

文件.add(退出);

编辑.add(复制);

编辑.add(粘贴);

编辑.add(剪切);

编辑.add(全选);

格式.add(字体);

帮助.add(关于);

setJMenuBar(mb);

Container container = getContentPane();

editorArea = new JTextArea();

editorArea.setLineWrap(true);

editorArea.addKeyListener(new KeyAdapter() {

public void keyPressed(KeyEvent e) {

if(!isDirty()){

setDirty(true);

}

}

});

JScrollPane scrollPane = new JScrollPane(editorArea);

container.add(scrollPane);

addWindowListener(new WindowAdapter() {

public void windowClosing(WindowEvent e){

dispose();

}

});

setTitle(formatEditorTitle());

setSize(600, 400);

setVisible(true);

}

private boolean isDirty() {

return isDirty;

}

private void setDirty(boolean isDirty) {

this.isDirty = isDirty;

setTitle(formatEditorTitle());

}

public static void main(String args[]) {

@SuppressWarnings("unused")

MyText app = new MyText();

}

public void actionPerformed(ActionEvent e) {

JMenuItem item = (JMenuItem)e.getSource();

if(item.equals(新建)){

if(isDirty()){

int ret = JOptionPane.showConfirmDialog(getContentPane(), "文件内容已经变动，是否保存？", "MyText", JOptionPane.YES_NO_CANCEL_OPTION, JOptionPane.WARNING_MESSAGE);

if(ret == JOptionPane.OK_OPTION){

saveFile();

}else if(ret == JOptionPane.CANCEL_OPTION || ret == JOptionPane.CLOSED_OPTION){

return;

}

}

clearEditorArea();

setDirty(false);

}else if(item.equals(打开)){

if(isDirty()){

int ret = JOptionPane.showConfirmDialog(getContentPane(), "文件内容已经变动，是否保存？", "MyText", JOptionPane.YES_NO_CANCEL_OPTION, JOptionPane.WARNING_MESSAGE);

if(ret == JOptionPane.OK_OPTION){

saveFile();

}else if(ret == JOptionPane.CANCEL_OPTION || ret == JOptionPane.CLOSED_OPTION){

return;

}

}

openFile();

}else if(item.equals(保存)){

saveFile();

}else if(item.equals(退出)){

dispose();

}else if(item.equals(复制)){

editorArea.copy();

}else if(item.equals(剪切)){

editorArea.cut();

}else if(item.equals(粘贴)){

editorArea.paste();

}else if(item.equals(全选)){

editorArea.selectAll();

}else if(item.equals(字体)){

FontDialog font = new FontDialog(this, editorArea.getFont());

editorArea.setFont(font.getSelectedFont());

}else if(item.equals(关于)){

AboutDialog about = new AboutDialog(this);

about.setVisible(true);

}

}

private String getFileName() {

return strFileName;

}

private void setFileName(String strFileName) {

this.strFileName = strFileName;

}

public String formatEditorTitle(){

StringBuffer strFileNm = new StringBuffer(getFileName());

strFileNm.append(isDirty()?"*":"");

strFileNm.append(" - ");

strFileNm.append(EDITOR_NAME);

return strFileNm.toString();

}

private void clearEditorArea(){

editorArea.selectAll();

editorArea.replaceSelection("");

}

private void openFile(){

JFileChooser openDialog = new JFileChooser();

openDialog.setFileFilter(new TxtFileFilter());

if(openDialog.showOpenDialog(getContentPane()) == JFileChooser.APPROVE_OPTION){

File file = openDialog.getSelectedFile();

BufferedReader br = null;

try {

br = new BufferedReader(new FileReader(file));

String buff = br.readLine();

clearEditorArea();

while(buff != null){

editorArea.append(buff);

editorArea.append("\n");

buff = br.readLine();

}

} catch (FileNotFoundException e1) {

e1.printStackTrace();

} catch (IOException ioe) {

ioe.printStackTrace();

} finally{

try{

if(br != null)

br.close();

} catch (IOException ioe){

ioe.printStackTrace();

}

}

}

}

private void saveFile(){

JFileChooser saveDialog = new JFileChooser();

saveDialog.setFileFilter(new TxtFileFilter());

if(saveDialog.showSaveDialog(getContentPane()) == JFileChooser.APPROVE_OPTION){

File file = saveDialog.getSelectedFile();

BufferedWriter bw = null;

try {

bw = new BufferedWriter(new FileWriter(file));

String buff = editorArea.getText();

bw.write(buff);

} catch (IOException ioe) {

ioe.printStackTrace();

} finally{

try{

if(bw != null)

bw.close();

} catch (IOException ioe){

ioe.printStackTrace();

}

}

}

}

class TxtFileFilter extends FileFilter{

@Override

public boolean accept(File f) {

return f.isDirectory() || f.getName().toLowerCase().endsWith(".txt");

}

@Override

public String getDescription() {

return "*.txt(文本文件)";

}

}

class FontDialog extends JDialog{

private JComboBox cb_FontSize;

private JComboBox cb_FontStyle;

private JComboBox cb_FontNm;

private Font font;

HashtableInteger, String style = new HashtableInteger, String();

public FontDialog(){

this(null, null);

}

public FontDialog(Frame owner, Font font){

super(owner);

this.font = font == null?getFont():font;

setTitle("字体选择框");

setModal(true);

setResizable(false);

setSize(326, 164);

getContentPane().setLayout(null);

final JLabel lb_FontNm = new JLabel();

lb_FontNm.setText("字体名称");

lb_FontNm.setBounds(10, 10, 66, 16);

getContentPane().add(lb_FontNm);

cb_FontNm = new JComboBox();

cb_FontNm.setBounds(10, 28, 133, 25);

getContentPane().add(cb_FontNm);

cb_FontStyle = new JComboBox();

cb_FontStyle.setBounds(169, 28, 66, 25);

getContentPane().add(cb_FontStyle);

cb_FontSize = new JComboBox();

cb_FontSize.setBounds(258, 28, 53, 25);

getContentPane().add(cb_FontSize);

final JButton btn_OK = new JButton();

btn_OK.addActionListener(new ActionListener() {

public void actionPerformed(ActionEvent e) {

int styleCode = 0;

for(EnumerationInteger i = style.keys();i.hasMoreElements();){

styleCode = i.nextElement();

if(style.get(styleCode).equals(cb_FontStyle.getSelectedItem()))

break;

}

Font font = new Font(cb_FontNm.getSelectedItem().toString(), styleCode, ((Integer)cb_FontSize.getSelectedItem()).intValue());

setSelectedFont(font);

dispose();

}

});

btn_OK.setText("确定");

btn_OK.setBounds(58, 83, 76, 26);

getContentPane().add(btn_OK);

final JButton btn_Cancel = new JButton();

btn_Cancel.addActionListener(new ActionListener() {

public void actionPerformed(ActionEvent e) {

dispose();

}

});

btn_Cancel.setText("取消");

btn_Cancel.setBounds(169, 83, 76, 26);

getContentPane().add(btn_Cancel);

final JLabel lb_FontStyle = new JLabel();

lb_FontStyle.setText("字体样式");

lb_FontStyle.setBounds(169, 10, 66, 16);

getContentPane().add(lb_FontStyle);

final JLabel lb_FontSize = new JLabel();

lb_FontSize.setText("字体大小");

lb_FontSize.setBounds(258, 10, 66, 16);

getContentPane().add(lb_FontSize);

init();

setVisible(true);

}

private void init(){

GraphicsEnvironment gg=GraphicsEnvironment.getLocalGraphicsEnvironment();

String ss[]=gg.getAvailableFontFamilyNames();

for(String s : ss)

cb_FontNm.addItem(s);

if(font != null)

cb_FontNm.setSelectedItem(font.getFamily());

style.put(Font.PLAIN, "标准");

style.put(Font.BOLD, "粗体");

style.put(Font.ITALIC, "斜体");

style.put(Font.BOLD+Font.ITALIC, "粗体斜体");

cb_FontStyle.addItem(style.get(Font.PLAIN));

cb_FontStyle.addItem(style.get(Font.BOLD));

cb_FontStyle.addItem(style.get(Font.ITALIC));

cb_FontStyle.addItem(style.get(Font.BOLD+Font.ITALIC));

if(font != null)

cb_FontStyle.setSelectedItem(style.get(font.getStyle()));

for(int i=8;i23;i++)

cb_FontSize.addItem(i);

if(font != null)

cb_FontSize.setSelectedItem(font.getSize());

}

public Font getSelectedFont() {

return font;

}

public void setSelectedFont(Font font) {

this.font = font;

}

}

class AboutDialog extends JDialog{

public AboutDialog(JFrame owner){

super(owner);

setTitle("关于");

setSize(new Dimension(322, 163));

getContentPane().setLayout(null);

final JLabel version = new JLabel();

version.setText("MyText 1.0");

version.setBounds(74, 37, 66, 16);

getContentPane().add(version);

final JLabel copyright = new JLabel();

copyright.setText("Copyright (C) 2010");

copyright.setBounds(74, 59, 188, 16);

getContentPane().add(copyright);

final JSeparator separator = new JSeparator();

separator.setBounds(70, 90, 210, 2);

getContentPane().add(separator);

final JButton okButton = new JButton();

okButton.setBounds(235, 95, 50, 26);

getContentPane().add(okButton);

okButton.setText("Ok");

okButton.addActionListener(new ActionListener() {

public void actionPerformed(ActionEvent e) {

dispose();

}

});

}

}

}

电脑怎么用记事本写Java程序并运行？

1. 新建一个记事本，后缀名是  .java  ；然后在里面写一段java的代码，如图：

2.把写好的java文件丢进D盘，就是第一步给出的那个class文件；

3. 打开dos界面 开始-〉运行-〉cmd-〉 这个是命令行模式,选择D盘，如图：

4.选择D盘之后，在命令提示符中输入“javac 文件名.java”,我的文件名为java，所以输入javac java.java然后回车，等待编译。这时候你就会发现它提示说javac不是内部文件。接下来就是java环境变量设置的问题了；

5.下载一个jdk执行默认安装。例如我下的jdk版本是： jdk-6u10-rc2-bin-b32-windows-i586-p-12_sep_2008.exe；

6.配置环境：右击我的电脑点属性，进去点高级就能看到环境变量。点进去就能设置你的系统变量了，如图：

6-1。变量名：classpath    变量值：(.;C:\Program Files\Java\jdk1.6.0_10\lib;)括号里面都是 （主要我们在编译运行程序的时候通过classpath可以帮助我们找到一些需要的系统类，“.”号是表示当前路径；“;”号是用来隔开多个变量值，如果你的系统里面已经有classpath环 境变量，就不用新建了，直接加“;”号，在后面加新值）；如图所示