trunk/workflowmodel-api/src/main/java/net/sf/taverna/t2/workflowmodel/OutputPort.java

/*******************************************************************************
 * 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.workflowmodel;

/**
 * Port representing the output of an activity, processor or workflow. In addition
 * to the name and port depth defined by the Port interface this includes a
 * granular depth property. The granular depth of an output is the depth of the
 * finest grained entity that can be emitted from that port. For example, if a
 * process conceptually returned a list of strings but was actually capable of
 * streaming strings as they were generated it would set a port depth of 1 and
 * granular depth of zero.
 * 
 * @author Tom Oinn
 * 
 */
public interface OutputPort extends Port {

	/**
	 * The granular depth is the depth of the finest grained item that can be
	 * emitted from this output port. A difference in this and the port depth
	 * indicates that the entity this port is attached to is capable of
	 * streaming data resulting from a single process invocation. The port depth
	 * defines the conceptual depth, so a process returning a stream of single
	 * items would set port depth to 1 and granular depth to zero.
	 * 
	 * @return granular depth of output port
	 */
	public int getGranularDepth();

}