    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.Collections;
    024import java.util.Comparator;
    025import java.util.Iterator;
    026import java.util.List;
    027import java.util.Map;
    028import java.util.Set;
    029
    030import cascading.flow.FlowElement;
    031import cascading.flow.FlowNode;
    032import cascading.flow.planner.BaseFlowNode;
    033import cascading.flow.planner.BaseFlowNodeFactory;
    034import cascading.flow.planner.graph.ElementGraph;
    035import cascading.flow.planner.graph.FlowElementGraph;
    036
    037import static cascading.util.Util.createIdentitySet;
    038
    039/**
    040 *
    041 */
    042public class FlowNodeGraph extends BaseProcessGraph<FlowNode>
    043  {
    044  public static final FlowNodeComparator FLOW_NODE_COMPARATOR = new FlowNodeComparator();
    045
    046  /**
    047   * Class FlowNodeComparator provides a consistent tie breaker when ordering nodes topologically.
    048   * <p/>
    049   * This should have no effect on submission and execution priority as all FlowNodes are submitted simultaneously.
    050   */
    051  public static class FlowNodeComparator implements Comparator<FlowNode>
    052    {
    053    @Override
    054    public int compare( FlowNode lhs, FlowNode rhs )
    055      {
    056      // larger graph first
    057      int lhsSize = lhs.getElementGraph().vertexSet().size();
    058      int rhsSize = rhs.getElementGraph().vertexSet().size();
    059      int result = ( lhsSize < rhsSize ) ? -1 : ( ( lhsSize == rhsSize ) ? 0 : 1 );
    060
    061      if( result != 0 )
    062        return result;
    063
    064      // more inputs second
    065      lhsSize = lhs.getSourceElements().size();
    066      rhsSize = rhs.getSourceElements().size();
    067
    068      return ( lhsSize < rhsSize ) ? -1 : ( ( lhsSize == rhsSize ) ? 0 : 1 );
    069      }
    070    }
    071
    072  public FlowNodeGraph()
    073    {
    074    }
    075
    076  public FlowNodeGraph( FlowElementGraph flowElementGraph, List<? extends ElementGraph> nodeSubGraphs )
    077    {
    078    this( new BaseFlowNodeFactory(), flowElementGraph, nodeSubGraphs );
    079    }
    080
    081  public FlowNodeGraph( FlowNodeFactory flowNodeFactory, List<? extends ElementGraph> nodeSubGraphs )
    082    {
    083    this( flowNodeFactory, null, nodeSubGraphs );
    084    }
    085
    086  public FlowNodeGraph( FlowNodeFactory flowNodeFactory, FlowElementGraph flowElementGraph, List<? extends ElementGraph> nodeSubGraphs )
    087    {
    088    this( flowNodeFactory, flowElementGraph, nodeSubGraphs, Collections.<ElementGraph, List<? extends ElementGraph>>emptyMap() );
    089    }
    090
    091  public FlowNodeGraph( FlowNodeFactory flowNodeFactory, FlowElementGraph flowElementGraph, List<? extends ElementGraph> nodeSubGraphs, Map<ElementGraph, List<? extends ElementGraph>> pipelineSubGraphsMap )
    092    {
    093    buildGraph( flowNodeFactory, flowElementGraph, nodeSubGraphs, pipelineSubGraphsMap );
    094
    095    // consistently sets ordinal of node based on topological dependencies and tie breaking by the given Comparator
    096    Iterator<FlowNode> iterator = getOrderedTopologicalIterator();
    097
    098    int ordinal = 0;
    099    int size = vertexSet().size();
    100
    101    while( iterator.hasNext() )
    102      {
    103      BaseFlowNode next = (BaseFlowNode) iterator.next();
    104
    105      next.setOrdinal( ordinal );
    106      next.setName( flowNodeFactory.makeFlowNodeName( next, size, ordinal ) );
    107
    108      ordinal++;
    109      }
    110    }
    111
    112  protected void buildGraph( FlowNodeFactory flowNodeFactory, FlowElementGraph flowElementGraph, List<? extends ElementGraph> nodeSubGraphs, Map<ElementGraph, List<? extends ElementGraph>> pipelineSubGraphsMap )
    113    {
    114    if( pipelineSubGraphsMap == null )
    115      pipelineSubGraphsMap = Collections.emptyMap();
    116
    117    for( ElementGraph nodeSubGraph : nodeSubGraphs )
    118      {
    119      List<? extends ElementGraph> pipelineGraphs = pipelineSubGraphsMap.get( nodeSubGraph );
    120
    121      FlowNode flowNode = flowNodeFactory.createFlowNode( flowElementGraph, nodeSubGraph, pipelineGraphs );
    122
    123      addVertex( flowNode );
    124      }
    125
    126    bindEdges();
    127    }
    128
    129  public Set<FlowElement> getFlowElementsFor( Enum annotation )
    130    {
    131    Set<FlowElement> results = createIdentitySet();
    132
    133    for( FlowNode flowNode : vertexSet() )
    134      results.addAll( flowNode.getFlowElementsFor( annotation ) );
    135
    136    return results;
    137    }
    138
    139  public Iterator<FlowNode> getOrderedTopologicalIterator()
    140    {
    141    return super.getOrderedTopologicalIterator( FLOW_NODE_COMPARATOR );
    142    }
    143  }