taverna-workflowmodel-api/src/main/java/org/apache/taverna/workflowmodel/OutputPort.java

/*
* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. The ASF licenses this file
* to you under the Apache License, Version 2.0 (the
* "License"); you may not use this file except in compliance
* with the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing,
* software distributed under the License is distributed on an
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package org.apache.taverna.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
	 */
	int getGranularDepth();
}