private PrintWriter out;  
public Server()  
{  
try  
{  
ss=new ServerSocket(10000);  
while(true)  
{  
socket = ss.accept();  
String RemoteIP = socket.getInetAddress().getHostAddress();  
String RemotePort = ":"+socket.getLocalPort();  
System.out.println("A client come in!IP:"+RemoteIP+RemotePort);  
in = new BufferedReader(new  
InputStreamReader(socket.getInputStream()));  
String line = in.readLine();  
System.out.println("Cleint send is :" + line);  
out = new PrintWriter(socket.getOutputStream(),true);  
out.println("Your Message Received!");  
out.close();  
in.close();  
socket.close();  
}  
}catch (IOException e)  
{  
out.println("wrong");  
}  
}  
public static void main(String[] args)  
{  
new Server();  
}  
};  
Client端程序:  
package test;  
import java.io.*;  
import java.net.*;  
public class Client  
{  
Socket socket;  
BufferedReader in;  
PrintWriter out;  
public Client()  
{  
try  
{  
System.out.println("Try to Connect to 127.0.0.1:10000");  
socket = new Socket("127.0.0.1",10000);  
System.out.println("The Server Connected!");  
System.out.println("Please enter some Character:");  
BufferedReader line = new BufferedReader(new  
InputStreamReader(System.in));  
out = new PrintWriter(socket.getOutputStream(),true);  
out.println(line.readLine());  
in = new BufferedReader(new InputStreamReader(socket.getInputStream()));  
System.out.println(in.readLine());  
out.close(); 
 
in.close(); 
socket.close();  
}catch(IOException e)  
{  
out.println("Wrong");  
}  
}  
public static void main(String[] args)  
{  
new Client();  
}  
};