com.mozilla.grouperfish.pig.storage.LDACStorage.java Source code

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Here is the source code for com.mozilla.grouperfish.pig.storage.LDACStorage.java

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/*
 * Copyright 2011 Mozilla Foundation
 *
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you under the Apache License, Version 2.0 (the
 * "License"); you may not use this file except in compliance
 * with the License.  You may obtain a copy of the License at
 *
 *   http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package com.mozilla.grouperfish.pig.storage;

import java.io.IOException;

import org.apache.hadoop.fs.Path;
import org.apache.hadoop.io.LongWritable;
import org.apache.hadoop.io.NullWritable;
import org.apache.hadoop.io.Text;
import org.apache.hadoop.mapreduce.Job;
import org.apache.hadoop.mapreduce.OutputFormat;
import org.apache.hadoop.mapreduce.RecordWriter;
import org.apache.hadoop.mapreduce.lib.output.FileOutputFormat;
import org.apache.hadoop.mapreduce.lib.output.TextOutputFormat;
import org.apache.log4j.Logger;
import org.apache.pig.StoreFunc;
import org.apache.pig.data.DataType;
import org.apache.pig.data.Tuple;

public class LDACStorage extends StoreFunc {

    private static final Logger LOG = Logger.getLogger(MahoutVectorStorage.class);

    private static final String SPACE = " ";
    private static final String COLON = ":";

    @SuppressWarnings("rawtypes")
    protected RecordWriter writer = null;

    private Text outputKey = new Text();
    private NullWritable outputValue = NullWritable.get();

    public LDACStorage() {
        super();
    }

    @SuppressWarnings("rawtypes")
    @Override
    public OutputFormat getOutputFormat() throws IOException {
        return new TextOutputFormat<LongWritable, Text>();
    }

    @SuppressWarnings("rawtypes")
    @Override
    public void prepareToWrite(RecordWriter writer) throws IOException {
        this.writer = writer;
    }

    @SuppressWarnings("unchecked")
    @Override
    public void putNext(Tuple tuple) throws IOException {
        Tuple vectorTuple = (Tuple) tuple.get(1);
        int vectorSize = vectorTuple.size();
        StringBuilder sb = new StringBuilder(vectorSize + SPACE);
        for (int i = 0; i < vectorSize; i++) {
            Object o = vectorTuple.get(i);
            switch (vectorTuple.getType(i)) {
            case DataType.INTEGER:
                // If this is just an integer then we just want to set the index to 1.0
                sb.append((Integer) o);
                if ((i + 1) < vectorSize) {
                    sb.append(SPACE);
                }
                break;
            case DataType.TUPLE:
                // If this is a tuple then we want to set the index and the weight/frequency
                Tuple subt = (Tuple) o;
                sb.append((Integer) subt.get(0));
                sb.append(COLON);
                sb.append((Double) subt.get(1));
                if ((i + 1) < vectorSize) {
                    sb.append(SPACE);
                }
                break;
            default:
                throw new RuntimeException("Unexpected tuple form");
            }
        }
        try {
            outputKey.set(sb.toString());
            writer.write(outputKey, outputValue);
        } catch (InterruptedException e) {
            LOG.error("Interrupted while writing", e);
        }
    }

    @Override
    public void setStoreLocation(String location, Job job) throws IOException {
        job.setOutputKeyClass(Text.class);
        job.setOutputValueClass(NullWritable.class);
        FileOutputFormat.setOutputPath(job, new Path(location));
    }

}