edu.cuhk.hccl.hadoop.TripAdvisorMapper.java Source code

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Here is the source code for edu.cuhk.hccl.hadoop.TripAdvisorMapper.java

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/**
 * Copyright (C) 2014 Pengfei Liu <pfliu@se.cuhk.edu.hk>
 * The Chinese University of Hong Kong.
 *
 * This file is part of aspect-opinion.
 *
 * Licensed 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 edu.cuhk.hccl.hadoop;

import java.io.IOException;

import org.apache.hadoop.io.LongWritable;
import org.apache.hadoop.io.Text;

import edu.cuhk.hccl.data.DataRecord;
import edu.cuhk.hccl.util.Constant;

public class TripAdvisorMapper extends BaseMapper {

    private final int NUM_LINES = 5;
    private String hotelID;

    @Override
    protected void setup(Context context) throws IOException, InterruptedException {
        aspects = Constant.TRIPADVISOR_ASPECTS;
    }

    @Override
    public void map(LongWritable key, Text value, Context context) throws IOException, InterruptedException {
        hotelID = key.toString();

        String[] lines = value.toString().split("\n");
        StringBuilder buffer = new StringBuilder();
        Text fiveLines = new Text();
        for (int i = 1; i <= lines.length; i++) {
            buffer.append(lines[i - 1] + "\n");
            if (i % NUM_LINES == 0) {
                fiveLines.set(buffer.toString());
                DataRecord record = parseDataRecord(fiveLines);
                if (record != null)
                    processRecord(record, context);
                buffer.setLength(0);
                ;
            }
        }

        // Report progress
        context.getCounter(Counters.INPUT_REVIEWS).increment(1);
    }

    public DataRecord parseDataRecord(Text value) {
        DataRecord record = new DataRecord();

        record.setItemID(hotelID);
        String[] lines = value.toString().split("\n");
        for (String line : lines) {
            try {
                if (line.startsWith("<Author>")) {
                    record.setUserID(line.split(">")[1].trim());
                } else if (line.startsWith("<Content>")) {
                    String content = line.split(">")[1].trim();
                    if (content == null || content.equals(""))
                        return null;
                    else
                        record.setReview(content);
                } else if (line.startsWith("<Rating>")) {
                    String[] rates = line.split(">")[1].trim().split("\t");
                    record.setRating(Integer.parseInt(rates[0]));
                }
            } catch (ArrayIndexOutOfBoundsException e) {
                System.out.print(e.getMessage());
            }
        }
        return record;
    }
}