先建两个Java Project项目，一个写Client，一个写Server端程序，程序大致为一个Server端建立监听某个port。多个Client端能够连接，实现例如以下：

1.      Server端

importjava.io.*;

importjava.net.*;

importjava.util.*;

publicclass SimpleChatServer {

ArrayList<PrintWriter>clientOutputStreams;

public static void main(String[]args){

new SimpleChatServer().go();

}

public class ClientHandler implementsRunnable{

BufferedReader reader;

Socket sock;

public ClientHandler(SocketclientSocket){

try{

sock = clientSocket;

InputStreamReader isReader =new InputStreamReader(sock.getInputStream());

reader = newBufferedReader(isReader);

}catch(Exception ex){

ex.printStackTrace();

}

}

public void run() {

String message;

try{

while((message =reader.readLine()) != null){

System.out.println("read " + message);

tellEveryone(message);

}

}catch(Exception ex){

ex.printStackTrace();

}

}

}

public void tellEveryone(Stringmessage){

Iterator<PrintWriter> it =clientOutputStreams.iterator();

while(it.hasNext()){

try{

PrintWriter writer =(PrintWriter)it.next();

writer.println(message);

writer.flush();

}catch(Exception ex){

ex.printStackTrace();

}

}

}

public void go(){

clientOutputStreams = newArrayList<PrintWriter>();

try{

ServerSocket serverSock = newServerSocket(2310);

while(true){

Socket clientSocket =serverSock.accept();

PrintWriter writer = newPrintWriter(clientSocket.getOutputStream());

clientOutputStreams.add(writer);

Thread t = new Thread(newClientHandler(clientSocket));

t.start();

System.out.println("got aconnection");

}

}catch(Exception ex){

ex.printStackTrace();

}

}

}

2.      Client端

importjava.io.*;

importjava.net.*;

importjavax.swing.*;

importjava.awt.*;

importjava.awt.event.*;

importjavax.swing.JOptionPane;

publicclass SimpleChatClient {

JTextArea incoming;

JTextField outgoing;

BufferedReader reader;

PrintWriter writer;

Socket sock;

static String clientName;

public static void main(String[] args){

SimpleChatClient client = newSimpleChatClient();

clientName = JOptionPane.showInputDialog("Pleaseinput the client name :");

client.go();

}

public void go() {

// build GUI

JFrame frame = new JFrame(clientName +"'s Chat Client");

JPanel mainPanel = new JPanel();

incoming = new JTextArea(15,20);

incoming.setLineWrap(true);

incoming.setWrapStyleWord(true);

incoming.setEditable(false);

JScrollPane qScroller = newJScrollPane(incoming);

qScroller.setVerticalScrollBarPolicy(ScrollPaneConstants.VERTICAL_SCROLLBAR_ALWAYS);

qScroller.setHorizontalScrollBarPolicy(ScrollPaneConstants.HORIZONTAL_SCROLLBAR_NEVER);

outgoing = new JTextField(20);

JButton sendButton = newJButton("Send");

sendButton.addActionListener(newSendButtonListener());

mainPanel.add(qScroller);

mainPanel.add(outgoing);

mainPanel.add(sendButton);

setUpNetworking();

Thread readerThread = new Thread(newIncomingReader());

readerThread.start();

frame.getContentPane().add(BorderLayout.CENTER, mainPanel);

frame.setSize(400,500);

frame.setVisible(true);

} // close go

private void setUpNetworking() {

try {

sock = newSocket("127.0.0.1", 2310);

InputStreamReader streamReader =new InputStreamReader(sock.getInputStream());

reader = newBufferedReader(streamReader);

writer = newPrintWriter(sock.getOutputStream());

System.out.println("networkingestablished");

} catch(IOException ex) {

ex.printStackTrace();

}

} // close setUpNetworking

public class SendButtonListener implementsActionListener {

public void actionPerformed(ActionEventev) {

try {

writer.println(clientName+" says:\n"+outgoing.getText());

writer.flush();

} catch(Exception ex) {

ex.printStackTrace();

}

outgoing.setText("");

outgoing.requestFocus();

}

}  //close SendButtonListener inner class

public class IncomingReader implementsRunnable {

public void run() {

String message = null;

try {

while ((message =reader.readLine()) != null) {

System.out.println("read " + message);

incoming.append(message +"\n");

} // close while

} catch(Exception ex){ex.printStackTrace();}

} // close run

} // close inner class

}

以下以Server端生成exe为例进行解说：

1.导出jar文件

选中你的项目---然后右击弹出选项列表---选择Export---Java---jarfile---next---browser(选择jar的存放路径)---next---next(无论太多继续下一步)---browser(选择你程序的主类--OK)---finish

2.安装exe4j

利用exe4j这个软件转换jar文件为exe文件,exe4j下载地址：http://www.ej-technologies.com/download/exe4j/files.html.

3.exe4j安装完毕后

1.执行后直接点Next.

2.选择第二项“JAR in EXE mode”,之后点击Next.

3.在General---Short name of your application框中输入你的应用程序的名字(随便就可以),在Directories---Outputdirectory框中输入生成exe后的保存路径,然后Next.

4.在Excutable name框中输入将要生成的exe的名字，“Icon File”是应用程序显示的小图标,不选也行.继续Next.

5.必须先配置Class-Path。点击+号加入文件，即jar文件，假设实用到其他资源须要把资源一起加入进去.

6.General --- Main Class选择主类.

7.Java Version --- Minimum version(低版本号必须填写)，Maximumversion(高版本号能够为空)。假设都有填写那么高版本号的值必须大于低版本号的值.

8.勾选Allow JREs with a beta version number以及Only allow JDKs andno JREs.接着Next.到这一步你能够直接finish.这样就把jar转换成exe文件了.你能够点击Click Here to Start the Applicationbutton測试生成的文件.

Client端生成exe步骤同上。