    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.tez.planner.rule.transformer;
    022
    023import cascading.flow.planner.iso.expression.ElementCapture;
    024import cascading.flow.planner.rule.transformer.BoundaryElementFactory;
    025import cascading.flow.planner.rule.transformer.RuleInsertionTransformer;
    026import cascading.flow.tez.planner.rule.expression.BalanceSplitToStreamedHashJoinExpression;
    027
    028import static cascading.flow.planner.rule.PlanPhase.BalanceAssembly;
    029
    030/**
    031 * Inserts Boundary after split that joins back into a HashJoin.
    032 * <p/>
    033 * this allows testGroupBySplitGroupByJoin to pass, and simplifies testJoinSamePipeAroundGroupBy by preventing
    034 * the upstream operations to duplicate processing in parallel nodes
    035 */
    036public class BoundaryBalanceSplitToStreamedHashJoinTransformer extends RuleInsertionTransformer
    037  {
    038  public BoundaryBalanceSplitToStreamedHashJoinTransformer()
    039    {
    040    super(
    041      BalanceAssembly,
    042      new BalanceSplitToStreamedHashJoinExpression(),
    043      ElementCapture.Secondary,
    044      BoundaryElementFactory.BOUNDARY_PIPE
    045    );
    046    }
    047  }