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.sparsecsv;
031
032import java.io.IOException;
033
034import org.apache.hadoop.io.LongWritable;
035import org.apache.hadoop.io.NullWritable;
036import org.apache.hadoop.io.Text;
037import org.apache.hadoop.mapreduce.Reducer;
038
039public class WordIndexSort {
040
041        public static class Reduce extends Reducer<LongWritable,Text,NullWritable,Text>{
042                
043                private int wordCountThresh;
044                private int wordsSeen;
045
046                public Reduce() {
047                        this.wordsSeen = 0;
048                }
049                
050                @Override
051                protected void setup(Reducer<LongWritable,Text,NullWritable,Text>.Context context) throws IOException ,InterruptedException {
052                        this.wordCountThresh = context.getConfiguration().getInt(WordIndex.WORDCOUNT_TOPN, -1);
053                        System.out.println("the top count loaded " + this.wordCountThresh);
054                };
055                
056                @Override
057                protected void reduce(LongWritable count, Iterable<Text> words, Reducer<LongWritable,Text,NullWritable,Text>.Context context) throws IOException ,InterruptedException {
058                        for (Text text : words) {
059                                if(this.wordCountThresh > 0 &&  wordsSeen > this.wordCountThresh)break;
060                                context.write(NullWritable.get(), text);
061                                wordsSeen++;
062                        }
063                };
064        }
065
066}