001/*
002 * Copyright (c) 2016-2017 Chris K Wensel <chris@wensel.net>. All Rights Reserved.
003 * Copyright (c) 2007-2017 Xplenty, Inc. All Rights Reserved.
004 *
005 * Project and contact information: http://www.cascading.org/
006 *
007 * This file is part of the Cascading project.
008 *
009 * Licensed under the Apache License, Version 2.0 (the "License");
010 * you may not use this file except in compliance with the License.
011 * You may obtain a copy of the License at
012 *
013 *     http://www.apache.org/licenses/LICENSE-2.0
014 *
015 * Unless required by applicable law or agreed to in writing, software
016 * distributed under the License is distributed on an "AS IS" BASIS,
017 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
018 * See the License for the specific language governing permissions and
019 * limitations under the License.
020 */
021
022package cascading.flow.planner.graph;
023
024import java.util.Collection;
025import java.util.Set;
026
027import cascading.flow.FlowElement;
028import cascading.flow.planner.Scope;
029import org.jgrapht.Graph;
030import org.jgrapht.graph.DirectedSubgraph;
031
032import static cascading.flow.planner.graph.ElementGraphs.directed;
033import static cascading.util.Util.createIdentitySet;
034
035/**
036 *
037 */
038public class ElementSubGraph extends BaseElementGraph implements ElementGraph
039  {
040  private final ElementGraph elementGraph;
041  private final Set<FlowElement> flowElements;
042  private final Set<Scope> scopes;
043
044  public ElementSubGraph( ElementGraph elementGraph, Collection<FlowElement> flowElements )
045    {
046    this( elementGraph, flowElements, null );
047    }
048
049  public ElementSubGraph( ElementGraph elementGraph, Collection<FlowElement> flowElements, Collection<Scope> scopes )
050    {
051    this.flowElements = createIdentitySet( flowElements );
052    this.scopes = scopes == null || scopes.isEmpty() ? null : createIdentitySet( scopes ); // forces edges to be induced
053    this.graph = new DirectedSubGraph( directed( elementGraph ), this.flowElements, this.scopes );
054    this.elementGraph = elementGraph;
055    }
056
057  public ElementSubGraph( ElementSubGraph graph )
058    {
059    this( graph.elementGraph, graph.flowElements, graph.scopes );
060    }
061
062  @Override
063  public ElementGraph copyElementGraph()
064    {
065    return new ElementSubGraph( this );
066    }
067
068  private class DirectedSubGraph extends DirectedSubgraph<FlowElement, Scope>
069    {
070    public DirectedSubGraph( Graph<FlowElement, Scope> base, Set<FlowElement> vertexSubset, Set<Scope> edgeSubset )
071      {
072      super( base, vertexSubset, edgeSubset );
073      }
074    }
075  }