server.java

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.PrintWriter;
import java.net.ServerSocket;
import java.net.Socket;
public class server {
 private static Socket client = null;
 private static ServerSocket socket = null;
 public static void main(String[] args) {
 // TODO Auto-generated method stub
 //default port
 int port = 1222;
 if (args.length != 1) {
 System.err.println("Considering Port 1222");
 // System.exit(1);
 }

 else {
 port = Integer.parseInt(args[0]);
 }
 try {
 socket = new ServerSocket(port);
 } catch(IOException e) {
 System.out.println(e.getMessage());
 }
 int countClients = 0;
 while(true) {
 try {
 client = socket.accept();
 countClients++;
 ClientThread thr = new ClientThread(client, 
countClients);
 thr.start();
 } catch (IOException e) {
 System.out.println(e.getMessage());
 }
 }
 }
}
class ClientThread extends Thread {

 private Socket client = null;
 private int clientNo = 0;
 public ClientThread(Socket socket, int n) {
 clientNo = n;
 client = socket;
 }
 public void run() {
 try {
 System.out.printf("Client %d Connected\n", clientNo);
 
 BufferedReader in = new BufferedReader(new 
InputStreamReader(client.getInputStream()));
 PrintWriter out = new PrintWriter(client.getOutputStream(), 
true);
 String input;
 while ((input = in.readLine()) != null) {
 System.out.printf("Received from client %d: %s\n", 
clientNo, input);
 out.println(input);
 }
 in.close();
 out.close();
 System.out.printf("Client %d Disconnected\n", clientNo);
 client.close();

 }
 catch (IOException e) {
 System.out.println(e.getMessage());
 }
 }
}