public static void main(String args[]) {
    DatagramSocket skt = null;
    try {
      skt = new DatagramSocket(6789);
      byte[] buffer = new byte[1000];
      while (true) {
        DatagramPacket request = new DatagramPacket(buffer, buffer.length);
        skt.receive(request);
        System.out.println("Data received from client");
        System.out.println(new String(request.getData()));
        Thread.sleep(15000);

        String[] arrayMsg = (new String(request.getData())).split(" ");

        System.out.println(arrayMsg[0] + "server processed");

        byte[] sendMsg = (arrayMsg[0] + "server processed").getBytes();

        DatagramPacket reply =
            new DatagramPacket(sendMsg, sendMsg.length, request.getAddress(), request.getPort());

        System.out.println("sending data from server to client");
        Thread.sleep(15000);
        ;
        skt.send(reply);
      }
    } catch (Exception e) {

    }
  }
  public static void main(String args[]) throws Exception {
    // Making a text file
    String filename =
        "C:\\Users\\S.S. Mehta\\Desktop\\Codes\\ComputerNetworks\\CN_project\\CN_project\\test3.txt";
    makeTextFile(filename);

    // Reading the file and puttin it in buffer
    BufferedReader in = new BufferedReader(new FileReader(filename));
    char[] c1 = new char[PACKET_SIZE];
    c1 = readData(in);
    displayPacket(c1);

    // Step3 - making a socket , makeing a packet with inet address and sending it
    byte[] buffer = new byte[PACKET_SIZE];
    DatagramSocket skt = new DatagramSocket(PORT_NUMBER);
    DatagramPacket request = new DatagramPacket(buffer, buffer.length);

    // stop till you receive
    wait(skt, request);
    System.out.println("On server side \nrequest received from Slient");
    // making a packet with an inet address -
    InetAddress host = InetAddress.getByName("localhost");

    DatagramPacket reply = makePacket(c1, host);

    // Sending reply packet
    System.out.println("Sending reply packet to client");
    Thread.sleep(5000);
    skt.send(reply);

    // closing the socket
    skt.close();
  }
 public static void wait(DatagramSocket skt, DatagramPacket request)
     throws IOException, InterruptedException {
   // stop till you receive
   skt.receive(request);
   System.out.println("request received");
   Thread.sleep(2000);
 }
Beispiel #4
0
  public static void main(String args[]) throws InterruptedException, IOException {
    int i, j;
    String serverInetAddress = "localhost";

    String server1AddressString = "10.10.1.1";
    InetAddress server1Address = InetAddress.getByName(server1AddressString);
    String server2AddressString = "10.10.2.2";
    InetAddress server2Address = InetAddress.getByName(server2AddressString);
    String server3AddressString = "10.10.3.2";
    InetAddress server3Address = InetAddress.getByName(server3AddressString);
    String server4AddressString = "localhost";
    InetAddress server4Address = InetAddress.getByName(server4AddressString);

    DatagramSocket skt;
    {
      skt = new DatagramSocket(PORT_NUMBER_CLIENT); // socket used to listen and write
      InetAddress host = InetAddress.getByName(serverInetAddress);
      int serversocket = S1.PORT_NUMBER_SERVER;

      String msg = "Send file size";
      byte[] b = msg.getBytes();

      // dummy assignments - not used anywhere
      int filesize = 1;
      DatagramPacket reply, request;
      reply = new DatagramPacket(b, b.length, host, serversocket);
      request = new DatagramPacket(b, b.length, host, serversocket);

      for (i = 1; i <= 3; i++) {
        // defining a packet called request with parameters b(msg in bytes), b.length, host Internet
        // address and socket number
        if (i == 1) {
          host = server1Address;
        } else if (i == 2) {
          host = server2Address;
        } else if (i == 3) {
          host = server3Address;
        }
        request = new DatagramPacket(b, b.length, host, serversocket);
        // System.out.println("request sent from client to server");
        Thread.sleep(S1.PAUSE_DURATION); // for error checks

        // Sending the packet- for getting the file size
        skt.send(request);

        //		getting reply from
        // server........................................................................................
        byte[] buffer =
            new byte
                [S1.PACKET_SIZE]; // apparently the size of data packet at the receiving side needs
                                  // to be bigger than the size of incoming datapacket
        reply = new DatagramPacket(buffer, buffer.length);

        // receiving packet from server - contatining filesize
        skt.receive(reply);
        // System.out.println("Response Received from server");

        // System.out.println("on Client: - filesize= "+new String(reply.getData()));
        filesize = Integer.parseInt(new String(reply.getData()).trim());
        // System.out.println("on Client: - filesize= "+filesize);
        Thread.sleep(S1.PAUSE_DURATION);
      }

      // here the client know the size of the file
      // Find the number of times it must make iterations - dividing filesize by packet_size
      // Request that many packets from server
      String[] buffer_string = new String[BUFFER_SIZE_CLIENT];
      float delay[] = new float[filesize / S1.PACKET_SIZE];
      System.out.println(filesize);
      System.out.println(S1.PACKET_SIZE);
      System.out.println(filesize / S1.PACKET_SIZE);
      Thread.sleep(2000);
      byte[] buffer = new byte[S1.PACKET_SIZE];
      for (i = 0; i < filesize / S1.PACKET_SIZE; i++) {
        if (i % 100 != 0) {
          // System.out.print(" "+i);
        } else {
          System.out.println(" " + i);
        }

        msg = String.valueOf(i);
        b = msg.getBytes();

        if (i % 3 == 0) {
          host = server1Address;
        } else if (i % 3 == 1) {
          host = server2Address;
        } else if (i % 3 == 2) {
          host = server3Address;
        }

        request = new DatagramPacket(b, b.length, host, serversocket);

        skt.send(request);
        delay[i] = System.nanoTime();
        Thread.sleep(10);
        skt.receive(reply);
        delay[i] = System.nanoTime() - delay[i];
        delay[i] = delay[i] / (1000000);
        /*
        if(empty_index<BUFFER_SIZE_CLIENT)
        {
        	buffer_string[empty_index]=new String(reply.getData());
        	empty_index++;
        }
        else
        {
        	for(j=0;j<BUFFER_SIZE_CLIENT-1;j++)
        	{
        		buffer_string[j]=buffer_string[j+1];
        	}
        	buffer_string[BUFFER_SIZE_CLIENT-1]=new String(reply.getData());
        }*/

        // display_buffer(buffer_string);
      }
      Arrays.sort(delay);
      float delay2[] = new float[filesize / S1.PACKET_SIZE];
      for (i = 0; i < delay2.length; i++) {
        delay2[i] = delay[delay.length - i - 1];
      }
      // delay2 stores the array in descending values

      float[] Sk = new float[filesize / S1.PACKET_SIZE];
      Sk[0] = (float) 0.0;

      for (i = 1; i < filesize / S1.PACKET_SIZE; i++) {
        for (j = 1; j <= i; j++) {
          Sk[i] = Sk[i] + delay2[j];
        }
        Sk[i] = Sk[i] / (10 * i);
      }
      make_output(Sk);
      System.out.format(
          "Sk at 2=%f\n,10=%f\n,20=%f\n,100=%f\n and 30000=%f\n ",
          Sk[1], Sk[9], Sk[19], Sk[99], Sk[29999]);
      // display_buffer(buffer_string);
      skt.close();
    }
  }
  public static void default_fn() throws IOException {
    // Declaring Socket for sending and receiving data
    DatagramSocket skt = null;
    // declaring the fields to be used
    String client_name, movie_name, time, cost, password, reply_string;
    int i, j;
    // assigning the socket a port number
    skt = new DatagramSocket(6789);
    // defining the buffer and its size
    byte[] buffer = new byte[1000];
    while (true) {
      // defining the packet to be received from client
      DatagramPacket request = new DatagramPacket(buffer, buffer.length);

      // receiving the packet
      skt.receive(request);

      // comment on the console
      System.out.println("Data received from client");

      // Thread.sleep(5000);//for error check

      // converting the message to string and then splitting it into fields divided by newline
      // character
      String[] arrayMsg = (new String(request.getData())).split("\n");
      client_name = arrayMsg[1];
      movie_name = arrayMsg[2];
      time = arrayMsg[3];
      cost = "$12";
      password = "******";

      // Composing the reply message by appending start time,cost and password
      reply_string = client_name + "\n" + movie_name + "\n" + time + "\n" + cost + "\n" + password;
      System.out.println(reply_string);
      // Thread.sleep(5000); for error check

      // converting string message to byte
      byte[] sendMsg = (reply_string).getBytes();

      // composing the data packet and sending it to the client's address and the same port the
      // client used
      DatagramPacket reply =
          new DatagramPacket(sendMsg, sendMsg.length, request.getAddress(), request.getPort());

      System.out.println("sending confirmation");

      // Thread.sleep(5000);//for error check

      // writing server log file
      PrintWriter writer = new PrintWriter("server_log.txt", "UTF-8");
      writer.println(client_name);
      writer.println(movie_name);
      writer.println(time);
      writer.close();

      // sending the data packet
      skt.send(reply);
      // Closing the server socket
      skt.close();
    }
  }