TinyChannel.java

/**
 *
 *    Placeholder for Radio Channel for RBO Protocol simulation in Java.
 *    
 *    Copyright (C) 2009  Marcin Kik
 *
 *    This program is free software; you can redistribute it and/or modify
 *    it under the terms of the GNU General Public License as published by
 *    the Free Software Foundation; either version 2 of the License, or
 *    (at your option) any later version.
 *
 *    This program is distributed in the hope that it will be useful,
 *    but WITHOUT ANY WARRANTY; without even the implied warranty of
 *    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *    GNU General Public License for more details.
 *
 *    You should have received a copy of the GNU General Public License
 *    along with this program; if not, write to the Free Software
 *    Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
 *
 *
 *    The author can be reached at Marcin.Kik@pwr.wroc.pl
 *
 */

// this implementation assumes single sender and single receiver;
// the receiver immediately removes the message from the channel


public class TinyChannel{

    volatile RboMessage message;

    public synchronized void setMessage(RboMessage msg)
    {
	message=msg;
	notify();
    }


    public synchronized RboMessage getMessage()
    {
	try
	    {
		while(message==null) wait();
	    }
	catch(Exception e)
	    {
		System.out.println(e);
		System.exit(-1);
	    }

	RboMessage copy=message;
	message=null;
	notify();
	return copy;
    }

}