001/**
002 * Copyright (c) 2011, The University of Southampton and the individual contributors.
003 * All rights reserved.
004 *
005 * Redistribution and use in source and binary forms, with or without modification,
006 * are permitted provided that the following conditions are met:
007 *
008 *   *  Redistributions of source code must retain the above copyright notice,
009 *      this list of conditions and the following disclaimer.
010 *
011 *   *  Redistributions in binary form must reproduce the above copyright notice,
012 *      this list of conditions and the following disclaimer in the documentation
013 *      and/or other materials provided with the distribution.
014 *
015 *   *  Neither the name of the University of Southampton nor the names of its
016 *      contributors may be used to endorse or promote products derived from this
017 *      software without specific prior written permission.
018 *
019 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
020 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
021 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
022 * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR
023 * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
024 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
025 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
026 * ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
027 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
028 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
029 */
030package org.openimaj.hadoop.tools.twitter.token.outputmode.timeseries;
031
032import java.util.List;
033
034import org.apache.hadoop.io.BytesWritable;
035import org.apache.hadoop.io.NullWritable;
036import org.apache.hadoop.io.Text;
037import org.apache.hadoop.mapreduce.Job;
038import org.apache.hadoop.mapreduce.Mapper;
039import org.apache.hadoop.mapreduce.Reducer;
040import org.openimaj.hadoop.mapreduce.stage.StageProvider;
041import org.openimaj.hadoop.mapreduce.stage.helper.SequenceFileTextStage;
042
043/**
044 * Given a set of specific words, this a mapper is prepared which emits only the dfidf values of those specific words
045 * and a reducer is created which emits a serialised time series for each word.
046 * @author Sina Samangooei (ss@ecs.soton.ac.uk)
047 *
048 */
049public class SpecificWordStageProvider extends StageProvider {
050
051        protected static final String WORD_TIME_SERIES = "org.openimaj.hadoop.tools.twitter.token.outputmode.timeseries.wts";
052        public static final String SPECIFIC_WORD = "specificword";
053        private List<String> wordtimeseries;
054
055        public SpecificWordStageProvider(List<String> wordtimeseries) {
056                this.wordtimeseries = wordtimeseries;
057        }
058
059        @Override
060        public SequenceFileTextStage<Text, BytesWritable, Text, BytesWritable, NullWritable, Text> stage() {
061                SequenceFileTextStage<Text,BytesWritable, Text, BytesWritable, NullWritable,Text> writeSpecificWords = new SequenceFileTextStage<Text,BytesWritable, Text, BytesWritable,NullWritable,Text>() {
062                        @Override
063                        public void setup(Job job) {
064                                job.getConfiguration().setStrings(WORD_TIME_SERIES, wordtimeseries.toArray(new String[wordtimeseries.size()]));
065                        }
066                        
067                        @Override
068                        public Class<? extends Mapper<Text, BytesWritable, Text, BytesWritable>> mapper() {
069                                return SpecificWordSelectionMapper.class;
070                        }
071                        
072                        @Override
073                        public Class<? extends Reducer<Text, BytesWritable, NullWritable, Text>> reducer() {
074                                return WordDFIDFTimeSeriesReducer.class;
075                        }
076                        
077                        @Override
078                        public String outname() {
079                                return SPECIFIC_WORD;
080                        }
081                };
082                return writeSpecificWords;
083        }
084
085}