001/* 002 * Copyright (c) 2016-2018 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.iso.transformer; 023 024import java.util.Set; 025 026import cascading.flow.FlowElement; 027import cascading.flow.planner.graph.ElementGraph; 028import cascading.flow.planner.graph.ElementGraphs; 029import cascading.flow.planner.iso.expression.ElementCapture; 030import cascading.flow.planner.iso.expression.ExpressionGraph; 031import cascading.flow.planner.iso.finder.Match; 032import cascading.util.Util; 033 034/** 035 * 036 */ 037public class RemoveBranchGraphTransformer extends MutateGraphTransformer 038 { 039 public RemoveBranchGraphTransformer( ExpressionGraph filter ) 040 { 041 super( filter ); 042 } 043 044 public RemoveBranchGraphTransformer( GraphTransformer graphTransformer, ExpressionGraph filter ) 045 { 046 super( graphTransformer, filter ); 047 } 048 049 @Override 050 protected boolean transformGraphInPlaceUsing( Transformed<ElementGraph> transformed, ElementGraph graph, Match match ) 051 { 052 Set<FlowElement> primary = match.getCapturedElements( ElementCapture.Primary ); 053 Set<FlowElement> secondary = match.getCapturedElements( ElementCapture.Secondary ); 054 055 if( primary.isEmpty() ) 056 return false; 057 058 if( secondary.isEmpty() ) 059 { 060 for( FlowElement flowElement : primary ) 061 { 062 boolean found = ElementGraphs.removeBranchContaining( graph, flowElement ); 063 064 if( !found ) 065 throw new IllegalStateException( "no branch found at: " + flowElement ); 066 } 067 } 068 else 069 { 070 // RemoveStreamedBranchTransformer uses a Secondary match to identify a branch but is currently unused 071 if( secondary.size() != 1 ) 072 throw new IllegalStateException( "too many captured secondary elements" ); 073 074 boolean found = ElementGraphs.removeBranchBetween( graph, Util.getFirst( primary ), Util.getFirst( secondary ), false ); 075 076 if( !found ) 077 throw new IllegalStateException( "no branch found between: " + Util.getFirst( primary ) + " and " + Util.getFirst( secondary ) ); 078 } 079 080 return true; 081 } 082 }