Java DatagramSocket create

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

public class Main {
  public static void main(String[] args) {
    final int LOCAL_PORT = 15900;
    final String SERVER_NAME = "localhost";

    try {/*from   w w w. ja  v  a2s. co  m*/
      DatagramSocket udpSocket = new DatagramSocket(LOCAL_PORT, InetAddress.getByName(SERVER_NAME));

      System.out.println("Created UDP server socket at " + udpSocket.getLocalSocketAddress() + "...");

      // Wait for a message in a loop and echo the same message to the sender
      while (true) {
        System.out.println("Waiting for a UDP packet" + " to arrive...");

        // Prepare a packet to hold the received data
        DatagramPacket packet = new DatagramPacket(new byte[1024], 1024);

        // Receive a packet
        udpSocket.receive(packet);

        // Print the packet details
        displayPacketDetails(packet);

        // Echo the same packet to the sender
        udpSocket.send(packet);
      }
    } catch (IOException e) {
      e.printStackTrace();
    }
  }

  public static void displayPacketDetails(DatagramPacket packet) {
    // Get the message
    byte[] msgBuffer = packet.getData();
    int length = packet.getLength();
    int offset = packet.getOffset();

    int remotePort = packet.getPort();
    InetAddress remoteAddr = packet.getAddress();
    String msg = new String(msgBuffer, offset, length);

    System.out.println("Received:[IP=" + remoteAddr + ", port=" + remotePort + ", message=" + msg + "]");
  }
}