/*******************************************************************************
 * Copyright (C) 2007 The University of Manchester   
 * 
 *  Modifications to the initial code base are copyright of their
 *  respective authors, or their employers as appropriate.
 * 
 *  This program is free software; you can redistribute it and/or
 *  modify it under the terms of the GNU Lesser General Public License
 *  as published by the Free Software Foundation; either version 2.1 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
 *  Lesser General Public License for more details.
 *    
 *  You should have received a copy of the GNU Lesser General Public
 *  License along with this program; if not, write to the Free Software
 *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307
 ******************************************************************************/
package net.sf.taverna.t2.lang.observer;

/**
 * Implement if you want to register with an {@link Observable}
 * 
 * @author Ian Dunlop
 * @author Stian Soiland
 * 
 * @param <Message>
 */
public interface Observer<Message> {
	/**
	 * Called by the {@link Observable} to notify the implementing class of
	 * changes
	 * 
	 * @param sender
	 *            the class where the changes have happened
	 * @param message
	 *            what has changed
	 * @throws Exception
	 */
	public void notify(Observable<Message> sender, Message message)
			throws Exception;
}