001/*
002 * Copyright (c) 2016-2017 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.pipe;
023
024import java.beans.ConstructorProperties;
025
026/**
027 * The Merge Pipe allows for multiple branches, with the same fields to be spliced back into a single stream.
028 * <p>
029 * The behavior is similar to the {@link GroupBy} merging features, but Merge does not perform any grouping or
030 * sorting on keys. Thus, when using a MapReduce platform, no Reducer is required.
031 * <p>
032 * Merge is non-blocking and performs no processing. Any number of branches and merges may be performed in a
033 * {@link cascading.flow.Flow} without triggering any additional MapReduce jobs on the Hadoop platform.
034 * <p>
035 * Unlike {@link HashJoin}, no preference need be made for left-hand or right-hand sided-ness of streams in relation
036 * to their sizes.
037 *
038 * @see GroupBy
039 */
040public class Merge extends Splice
041  {
042  /**
043   * Constructor Merge creates a new Merge instance.
044   *
045   * @param pipes
046   */
047  @ConstructorProperties({"pipes"})
048  public Merge( Pipe... pipes )
049    {
050    super( null, pipes );
051    }
052
053  /**
054   * Constructor Merge creates a new Merge instance.
055   *
056   * @param name
057   * @param pipes
058   */
059  @ConstructorProperties({"name", "pipes"})
060  public Merge( String name, Pipe... pipes )
061    {
062    super( name, pipes );
063    }
064  }