Java Socket exp

MyServer.java

import java.io.*;
import java.net.*;
import java.util.Scanner;
import java.util.NoSuchElementException;

public class MyServer{
	ServerSocket serverSocket;
	Socket clientSocket;
	Scanner in;
	BufferedWriter out;
	public void start(){
		try{
			// create a server
			serverSocket = new ServerSocket(8889, 5);
			while(true){
				// accept a client
				log("Waiting for client...");
				clientSocket = serverSocket.accept();
				log(String.format("Accepted client: %s", 
							clientSocket.getInetAddress().getHostName()));
				// build stream
				in = new Scanner(
						clientSocket.getInputStream());
				out = new BufferedWriter(
						new OutputStreamWriter(
							clientSocket.getOutputStream()));
				while(true){
					// read message from client
					try{
						String msg = recv();
						if(msg == null){
							break;
						}
					}catch(IOException ex){
						//pass
						break;
					}
				}
				log("Client quit.");
			}
		}catch(IOException ex){
			ex.printStackTrace();
		}
	}

	String recv() throws IOException{
		String msg;
		try{
			msg = in.nextLine();
		}catch(NoSuchElementException ex){
			return null;
		}
		log(String.format("Received: [%s]", msg));
		// reply
		out.write("ok\n");
		out.flush();
		return msg;
	}

	void log(String s){
		System.out.println(s);
	}

	static public void main(String[] args){
		MyServer server = new MyServer();
		server.start();
	}
};

/*
Reference:
    socket example: 
		http://zerioh.tripod.com/ressources/sockets.html
	java document:
		http://docs.oracle.com/javase/1.5.0/docs/api/java/lang/String.html
		http://docs.oracle.com/javase/1.4.2/docs/api/java/io/BufferedReader.html
		http://docs.oracle.com/javase/1.5.0/docs/api/java/util/Formatter.html
		http://docs.oracle.com/javase/1.4.2/docs/api/java/net/ServerSocket.html
		http://docs.oracle.com/javase/1.4.2/docs/api/java/net/Socket.html#bind%28java.net.SocketAddress%29
	search engine: 
		www.yahoo.com
*/