UDP Server 2

/*
 *tinh tong 2 so a + b gui tu CLient len server
 * tren Client can tao 2 goi gui 2 so a va b , va tao 1 goi de nhan 1 ket qua ve
 * tren Server can tao 2 goi nhan 2 so a va b, va tao 1 goi de gui ket qua ve
 */

import java.io.IOException;
import java.net.DatagramPacket;
import java.net.DatagramSocket;
import java.net.InetAddress;
import java.net.SocketException;
import java.net.UnknownHostException;

public class UDPServer {
    private final static int SERVER_PORT = 10000;
    private final static int CLIENT_PORT = 10001;

    public static void main(String[] args) {
        InetAddress clientAddr = null;
        DatagramSocket socket = null;
        try {
            //Initializing the UDP server
            System.out.println(String.format("Connecting on %s...", SERVER_PORT));
            socket = new DatagramSocket(SERVER_PORT);
            System.out.println("Connected.");
            System.out.println("====================");
        } catch (SocketException e) {
            e.printStackTrace();
        }

        while(true){
            try {
                //Listening
                byte[] buf = new byte[1024];
                DatagramPacket packet = new DatagramPacket(buf, buf.length);
                System.out.println("Listening...");
                socket.receive(packet);

                //Getting client address from the packet we received
                clientAddr = packet.getAddress();
                System.out.println("Received: '" + new String(packet.getData()).trim() + "' from "+clientAddr.toString());

                //Sending response
//                byte[] message = ("Hello Android").getBytes();
//                DatagramPacket response = new DatagramPacket(message, message.length, clientAddr, CLIENT_PORT);
//                DatagramSocket clientSocket = new DatagramSocket();
//                System.out.println("Sending: '" + new String(message) + "'");
//                clientSocket.send(response);
//                System.out.println("Response sent.");
//                System.out.println("--------------------");
            } catch (Exception e) {
                e.printStackTrace();
            }
        }
    }

}

//public class UDPServer {
//    public static void main(String []args) throws IOException
//    {
//        // tao ket noi
//        DatagramSocket serverSocket = new DatagramSocket(1024);
//        //thong bao server da san sang ket noi
//        System.out.println("Server is now already");
//
//
//
//        //tao mang byte de chua du lieu gui len tu client
//        byte inFromClient1[];
//        inFromClient1 = new byte[256];
//        byte inFromClient2[];
//        inFromClient2 = new byte[256];
//        // lay kich thuoc mang
//        int leng1 = inFromClient1.length;
//        int leng2 = inFromClient2.length;
//        // tao goi de nhan du lieu gui len tu client
//        DatagramPacket fromClient1 = new DatagramPacket(inFromClient1, leng1);
//        DatagramPacket fromClient2 = new DatagramPacket(inFromClient2, leng2);
//
//
//
//
//        // nhan goi ve server
//        serverSocket.receive(fromClient1);
//        serverSocket.receive(fromClient2);
//
//
//        // tao bien data kieu string de lay du lieu trong goi ra
//        String data1,data2;
//
//        // lay du lieu vao bien data
//        data1 = (new String(fromClient1.getData(),0,inFromClient1.length)).trim();
//        data2 = (new String(fromClient2.getData(),0,inFromClient2.length)).trim();
//        // chuyen du lieu tu kieu String -> integer
//        int a,b,tong;
//        a = Integer.parseInt(data1);
//        b = Integer.parseInt(data2);
//        // xu ly yeu cau
//        tong = a + b;
//        System.out.println(tong);
//        //chuyen du lieu tu kieu int -> String va truyen vao bien data
//        data1 = String.valueOf(tong);
//        // dong goi ket qua
//        byte outToClient[];
//        outToClient = data1.getBytes();
//        //lay kich thuoc mang
//        leng1 = outToClient.length;
//        //lay dia chi cua may khach, no nam luon trong goi ma da gui len server
//        InetAddress address = fromClient1.getAddress();
//        // lay so port
//        int port = fromClient1.getPort();
//        // tao goi de gui ve client
//        DatagramPacket toClient = new DatagramPacket(outToClient, leng1, address, port);
//        //gui goi ve client
//        serverSocket.send(toClient);
//        //dong socket
//        serverSocket.close();
//    }
//
//}