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.graph;
022
023import java.util.Collection;
024import java.util.Set;
025
026import cascading.flow.FlowElement;
027import cascading.flow.planner.Scope;
028import org.jgrapht.DirectedGraph;
029import org.jgrapht.graph.DirectedSubgraph;
030
031import static cascading.flow.planner.graph.ElementGraphs.directed;
032import static cascading.util.Util.createIdentitySet;
033
034/**
035 *
036 */
037public class ElementSubGraph extends BaseElementGraph implements ElementGraph
038  {
039  private final ElementGraph elementGraph;
040  private final Set<FlowElement> flowElements;
041  private final Set<Scope> scopes;
042
043  public ElementSubGraph( ElementGraph elementGraph, Collection<FlowElement> flowElements )
044    {
045    this( elementGraph, flowElements, null );
046    }
047
048  public ElementSubGraph( ElementGraph elementGraph, Collection<FlowElement> flowElements, Collection<Scope> scopes )
049    {
050    this.flowElements = createIdentitySet( flowElements );
051    this.scopes = scopes == null || scopes.isEmpty() ? null : createIdentitySet( scopes ); // forces edges to be induced
052    this.graph = new DirectedSubGraph( directed( elementGraph ), this.flowElements, this.scopes );
053    this.elementGraph = elementGraph;
054    }
055
056  public ElementSubGraph( ElementSubGraph graph )
057    {
058    this( graph.elementGraph, graph.flowElements, graph.scopes );
059    }
060
061  @Override
062  public ElementGraph copyElementGraph()
063    {
064    return new ElementSubGraph( this );
065    }
066
067  private class DirectedSubGraph extends DirectedSubgraph<FlowElement, Scope>
068    {
069    public DirectedSubGraph( DirectedGraph<FlowElement, Scope> base, Set<FlowElement> vertexSubset, Set<Scope> edgeSubset )
070      {
071      super( base, vertexSubset, edgeSubset );
072      }
073    }
074  }