001/*
002 * Copyright (c) 2007-2016 Concurrent, 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.planner.rule;
022
023/**
024 */
025public enum ProcessLevel
026  {
027    /**
028     * Applies assertions or transformations to the whole FlowElement assembly.
029     */
030    Assembly,
031
032    /**
033     * Applies to sub-graphs of a flow where a step is a submitted unit of cluster work.
034     */
035    Step,
036
037    /**
038     * Applies to generation sub-graphs of steps where is a node is a unit of processing with a step.
039     * <p/>
040     * In MapReduce its a Map or Reduce node (where Map and Reduce are Kinds).
041     * <p/>
042     * In Tez its a Processor.
043     */
044    Node,
045
046    /**
047     * Applies to sub-graphs within nodes having a single streamed input, and multiple accumulated inputs.
048     * <p/>
049     * In MapReduce, a Mapper task can arbitrarily process a given input file via the MultiInputSplit.
050     * <p/>
051     * Tez currently does not allow multiply physical inputs per processor.
052     */
053    Pipeline;
054
055  public static ProcessLevel parent( ProcessLevel level )
056    {
057    if( level == Assembly )
058      return null;
059
060    return ProcessLevel.values()[ level.ordinal() - 1 ];
061    }
062  }