001/* 002 * Copyright (c) 2016 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.hadoop.planner.rule.expression; 023 024import cascading.flow.planner.iso.expression.ElementCapture; 025import cascading.flow.planner.iso.expression.ExpressionGraph; 026import cascading.flow.planner.iso.expression.FlowElementExpression; 027import cascading.flow.planner.iso.expression.JoinEdgesSameSourceScopeExpression; 028import cascading.flow.planner.iso.expression.PathScopeExpression; 029import cascading.flow.planner.iso.expression.TypeExpression; 030import cascading.flow.planner.rule.RuleExpression; 031import cascading.flow.planner.rule.expressiongraph.SyncPipeExpressionGraph; 032import cascading.pipe.HashJoin; 033import cascading.pipe.Pipe; 034import cascading.tap.Tap; 035 036/** 037 * 038 */ 039public class BalanceHashJoinSameSourceExpression extends RuleExpression 040 { 041 public BalanceHashJoinSameSourceExpression() 042 { 043 super( 044 new SyncPipeExpressionGraph(), 045 046 new ExpressionGraph() 047 .arc( 048 new FlowElementExpression( ElementCapture.Primary, Tap.class, TypeExpression.Topo.SplitOnly ), 049 JoinEdgesSameSourceScopeExpression.ALL_SAME_SOURCE, 050 new FlowElementExpression( HashJoin.class ) 051 ), 052 053 new ExpressionGraph() 054 .arc( 055 new FlowElementExpression( ElementCapture.Secondary, Pipe.class ), 056 PathScopeExpression.BLOCKING, 057 new FlowElementExpression( ElementCapture.Primary, HashJoin.class ) 058 ) 059 ); 060 } 061 }