    001    /*
    002     * Copyright (c) 2007-2014 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
    021    package cascading.tap.hadoop.io;
    022
    023    import java.io.IOException;
    024
    025    import cascading.flow.FlowProcess;
    026    import cascading.flow.SliceCounters;
    027    import cascading.tap.Tap;
    028    import cascading.tap.hadoop.util.MeasuredOutputCollector;
    029    import cascading.tuple.TupleEntrySchemeCollector;
    030    import org.apache.hadoop.mapred.JobConf;
    031    import org.apache.hadoop.mapred.OutputCollector;
    032    import org.apache.hadoop.mapred.RecordReader;
    033
    034    /**
    035     * Class HadoopTupleEntrySchemeCollector is a kind of {@link cascading.tuple.TupleEntryCollector} that writes tuples to the resource managed by
    036     * a particular {@link cascading.tap.Tap} instance.
    037     */
    038    public class HadoopTupleEntrySchemeCollector extends TupleEntrySchemeCollector<JobConf, OutputCollector>
    039      {
    040      private MeasuredOutputCollector measuredOutputCollector;
    041
    042      public HadoopTupleEntrySchemeCollector( FlowProcess<JobConf> flowProcess, Tap<JobConf, RecordReader, OutputCollector> tap ) throws IOException
    043        {
    044        super( flowProcess, tap.getScheme(), makeCollector( flowProcess, tap, null ), tap.getIdentifier() );
    045        }
    046
    047      public HadoopTupleEntrySchemeCollector( FlowProcess<JobConf> flowProcess, Tap<JobConf, RecordReader, OutputCollector> tap, OutputCollector outputCollector ) throws IOException
    048        {
    049        super( flowProcess, tap.getScheme(), makeCollector( flowProcess, tap, outputCollector ), tap.getIdentifier() );
    050        }
    051
    052      private static OutputCollector makeCollector( FlowProcess<JobConf> flowProcess, Tap<JobConf, RecordReader, OutputCollector> tap, OutputCollector outputCollector ) throws IOException
    053        {
    054        if( outputCollector != null )
    055          return outputCollector;
    056
    057        return new TapOutputCollector( flowProcess, tap );
    058        }
    059
    060      @Override
    061      protected OutputCollector<?, ?> wrapOutput( OutputCollector outputCollector )
    062        {
    063        if( measuredOutputCollector == null )
    064          measuredOutputCollector = new MeasuredOutputCollector( getFlowProcess(), SliceCounters.Write_Duration );
    065
    066        measuredOutputCollector.setOutputCollector( outputCollector );
    067
    068        return measuredOutputCollector;
    069        }
    070      }