    001/*
    002 * Copyright (c) 2016 Chris K Wensel <chris@wensel.net>. 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.expression;
    022
    023import cascading.flow.planner.iso.expression.ElementCapture;
    024import cascading.flow.planner.iso.expression.ElementExpression;
    025import cascading.flow.planner.iso.expression.ExpressionGraph;
    026import cascading.flow.planner.iso.expression.FlowElementExpression;
    027import cascading.flow.planner.iso.expression.PathScopeExpression;
    028import cascading.flow.planner.iso.finder.SearchOrder;
    029import cascading.pipe.Group;
    030import cascading.pipe.HashJoin;
    031import cascading.pipe.Merge;
    032import cascading.tap.Tap;
    033
    034import static cascading.flow.planner.iso.expression.OrElementExpression.or;
    035
    036/**
    037 *
    038 */
    039public class StreamedAccumulatedTapsHashJoinExpressionGraph extends ExpressionGraph
    040  {
    041  public StreamedAccumulatedTapsHashJoinExpressionGraph()
    042    {
    043    super( SearchOrder.Depth );
    044
    045    FlowElementExpression split = new FlowElementExpression( Tap.class );
    046
    047    ElementExpression join = new FlowElementExpression( HashJoin.class );
    048
    049    ElementExpression merge = new FlowElementExpression( Merge.class );
    050
    051    ElementExpression sink = or(
    052      ElementCapture.Secondary,
    053      new FlowElementExpression( Tap.class ),
    054      new FlowElementExpression( Group.class )
    055    );
    056
    057    this.arc(
    058      new FlowElementExpression( ElementCapture.Primary, Tap.class ),
    059      PathScopeExpression.ALL_NON_BLOCKING,
    060      join
    061    );
    062
    063    this.arc(
    064      split,
    065      PathScopeExpression.ALL_BLOCKING, // if ANY_BLOCKING DualStreamedAccumulatedMergePipelineAssert will fire
    066      join
    067    );
    068
    069    this.arc(
    070      join,
    071      PathScopeExpression.ANY,
    072      merge
    073    );
    074
    075    this.arc(
    076      split,
    077      PathScopeExpression.NO_CAPTURE,
    078      merge
    079    );
    080
    081    this.arc(
    082      merge,
    083      PathScopeExpression.ANY,
    084      sink
    085    );
    086    }
    087  }