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.hadoop.planner.rule.expressiongraph;
022
023import cascading.flow.FlowElement;
024import cascading.flow.planner.PlannerContext;
025import cascading.flow.planner.graph.ElementGraph;
026import cascading.flow.planner.iso.expression.ElementCapture;
027import cascading.flow.planner.iso.expression.ExpressionGraph;
028import cascading.flow.planner.iso.expression.FlowElementExpression;
029import cascading.flow.planner.iso.expression.TypeExpression;
030import cascading.flow.planner.iso.finder.SearchOrder;
031import cascading.pipe.HashJoin;
032import cascading.pipe.Splice;
033
034import static cascading.flow.planner.iso.expression.AndElementExpression.and;
035import static cascading.flow.planner.iso.expression.NotElementExpression.not;
036
037/**
038 *
039 */
040public class MalformedJoinExpressionGraph extends ExpressionGraph
041  {
042  public MalformedJoinExpressionGraph()
043    {
044    super(
045      SearchOrder.ReverseDepth,
046      and( ElementCapture.Primary,
047        new FlowElementExpression( HashJoin.class )
048          {
049          @Override
050          public boolean applies( PlannerContext plannerContext, ElementGraph elementGraph, FlowElement flowElement )
051            {
052            return super.applies( plannerContext, elementGraph, flowElement ) && !( (Splice) flowElement ).isSelfJoin();
053            }
054          },
055        not( new FlowElementExpression( HashJoin.class, TypeExpression.Topo.SpliceOnly ) )
056      )
057    );
058    }
059  }