    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.planner.rule.expressiongraph;
    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.JoinEdgesSameSourceScopeExpression;
    028import cascading.flow.planner.iso.expression.OrElementExpression;
    029import cascading.flow.planner.iso.finder.SearchOrder;
    030import cascading.pipe.Group;
    031import cascading.pipe.Merge;
    032import cascading.tap.Tap;
    033
    034import static cascading.flow.planner.iso.expression.TypeExpression.Topo.Splice;
    035import static cascading.flow.planner.iso.expression.TypeExpression.Topo.Split;
    036
    037/**
    038 *
    039 */
    040public class LogicalMergeExpressionGraph extends ExpressionGraph
    041  {
    042  public LogicalMergeExpressionGraph()
    043    {
    044    super( SearchOrder.ReverseDepth );
    045
    046    ElementExpression source = OrElementExpression.or( ElementCapture.Primary, new FlowElementExpression( Tap.class, Split ), new FlowElementExpression( Group.class, Split ) );
    047    ElementExpression sink = new FlowElementExpression( ElementCapture.Secondary, Merge.class, Splice );
    048
    049    this.arc(
    050      source,
    051      JoinEdgesSameSourceScopeExpression.ALL_SAME_SOURCE,
    052      sink
    053    );
    054    }
    055  }