001/*
002 * Copyright (c) 2007-2017 Xplenty, Inc. All Rights Reserved.
003 *
004 * Project and contact information: http://www.cascading.org/
005 *
006 * This file is part of the Cascading project.
007 *
008 * Licensed under the Apache License, Version 2.0 (the "License");
009 * you may not use this file except in compliance with the License.
010 * You may obtain a copy of the License at
011 *
012 *     http://www.apache.org/licenses/LICENSE-2.0
013 *
014 * Unless required by applicable law or agreed to in writing, software
015 * distributed under the License is distributed on an "AS IS" BASIS,
016 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
017 * See the License for the specific language governing permissions and
018 * limitations under the License.
019 */
020
021package cascading.flow.planner.process;
022
023import java.util.Set;
024
025import cascading.flow.FlowElement;
026import cascading.flow.planner.graph.ElementGraph;
027import cascading.flow.planner.graph.ElementGraphs;
028import cascading.util.Util;
029
030/**
031 *
032 */
033public class ProcessModels
034  {
035  /**
036   * Does the given process perform any work?
037   *
038   * @param process
039   * @param excludingType
040   * @return
041   */
042  public static boolean isIdentity( ProcessModel process, Class<? extends FlowElement> excludingType )
043    {
044    ElementGraph elementGraph = ElementGraphs.asExtentMaskedSubGraph( process.getElementGraph() );
045
046    Set<? extends FlowElement> sourceElements = Util.narrowIdentitySet( excludingType, process.getSourceElements(), false );
047    Set<? extends FlowElement> sinkElements = Util.narrowIdentitySet( excludingType, process.getSinkElements(), false );
048
049    return elementGraph.vertexSet().size() == ( sourceElements.size() + sinkElements.size() );
050    }
051
052  /**
053   * Does the given process perform any work?
054   *
055   * @param process
056   * @return
057   */
058  public static boolean isIdentity( ProcessModel process )
059    {
060    ElementGraph elementGraph = ElementGraphs.asExtentMaskedSubGraph( process.getElementGraph() );
061
062    Set<FlowElement> sourceElements = process.getSourceElements();
063    Set<FlowElement> sinkElements = process.getSinkElements();
064
065    return elementGraph.vertexSet().size() == ( sourceElements.size() + sinkElements.size() );
066    }
067  }