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An open source implementation of the Distributed Interactive Simulation (DIS) IEEE-1278 protocol

There is a newer version: 5.8

package edu.nps.moves.examples;

import java.net.*;
import java.nio.*;

import edu.nps.moves.disutil.*;

import edu.nps.moves.dis.*;

/**
 * Receives PDUs from the network in IEEE format. Very similar to EspduReciver, but this
 * uses Robert Harder's more memory-efficient NIO code.
 *
 * @author DMcG rharder
 * @version $Id:$
 */
public class EspduReceiverNIO {

    /** Max size of a PDU in binary format that we can receive. This is actually
     * somewhat outdated--PDUs can be larger--but this is a reasonable starting point
     */
    public static final int MAX_PDU_SIZE = 8192; // This has actually been superceded by a larger buffer size, but good enough for now

    public static void main(String args[]) {
        MulticastSocket socket;
        DatagramPacket packet;
        InetAddress address;
        PduFactory pduFactory = new PduFactory();

        try {
            // Specify the socket to receive data
            socket = new MulticastSocket(EspduSender.PORT);
            address = InetAddress.getByName(EspduSender.DEFAULT_MULTICAST_GROUP);
            socket.joinGroup(address);

            // Loop infinitely, receiving datagrams
            while (true) {
                byte buffer[] = new byte[MAX_PDU_SIZE];
                packet = new DatagramPacket(buffer, buffer.length);

                socket.receive(packet);

                // Uses the NIO byte buffer class--wrap a ByteBuffer instance around
                // the data we get from the packet
                ByteBuffer byteBuffer = ByteBuffer.wrap(packet.getData());
                Pdu pdu = pduFactory.createPdu(byteBuffer);

                System.out.println("got PDU of type: " + pdu.getClass().getName());


            } // end while
        } // End try
        catch (Exception e) {

            System.out.println(e);
        }


    } // end main
} // end class