// MulticastSendingThread.java // MulticastSendingThread is a Thread that broadcasts a chat // message using a multicast datagram. package com.deitel.messenger.sockets.server; import java.io.*; import java.net.*; import com.deitel.messenger.sockets.*; public class MulticastSendingThread extends Thread { // message data private byte[] messageBytes; // MulticastSendingThread constructor public MulticastSendingThread( byte[] bytes ) { // invoke superclass constructor to name Thread super( "MulticastSendingThread" ); messageBytes = bytes; } // deliver message to MULTICAST_ADDRESS over DatagramSocket public void run() { // deliver message try { // create DatagramSocket for sending message DatagramSocket socket = new DatagramSocket( SocketMessengerConstants.MULTICAST_SENDING_PORT ); // use InetAddress reserved for multicast group InetAddress group = InetAddress.getByName( SocketMessengerConstants.MULTICAST_ADDRESS ); // create DatagramPacket containing message DatagramPacket packet = new DatagramPacket( messageBytes, messageBytes.length, group, SocketMessengerConstants.MULTICAST_LISTENING_PORT ); // send packet to multicast group and close socket socket.send( packet ); socket.close(); } // handle exception delivering message catch ( IOException ioException ) { ioException.printStackTrace(); } } // end method run } // end class MulticastSendingThread /************************************************************************** * (C) Copyright 1992-2003 by Deitel & Associates, Inc. and * * Prentice Hall. All Rights Reserved. * * * * DISCLAIMER: The authors and publisher of this book have used their * * best efforts in preparing the book. These efforts include the * * development, research, and testing of the theories and programs * * to determine their effectiveness. The authors and publisher make * * no warranty of any kind, expressed or implied, with regard to these * * programs or to the documentation contained in these books. The authors * * and publisher shall not be liable in any event for incidental or * * consequential damages in connection with, or arising out of, the * * furnishing, performance, or use of these programs. * *************************************************************************/