org.mapreduce.martin.mapreducewordcount.algorithms.Mapping.java Source code

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Here is the source code for org.mapreduce.martin.mapreducewordcount.algorithms.Mapping.java

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/*
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package org.mapreduce.martin.mapreducewordcount.algorithms;

import ch.qos.logback.classic.Logger;
import java.util.Collections;
import java.util.HashMap;
import java.util.Map;
import org.apache.commons.lang3.StringUtils;
import org.slf4j.LoggerFactory;

/**
 *
 * @author BRIGHTER AGYEMANG
 */
public class Mapping {
    private static final Logger logger = (Logger) LoggerFactory.getLogger(Mapping.class);
    private final String delimiter = " ";

    public Mapping() {
    }

    public Map<String, Integer> perfromMapping(String line) {
        String[] wordsInLine = line.split(delimiter);
        Map<String, Integer> tally = new HashMap<>();
        for (String word : wordsInLine) {
            doTally(word, tally, wordsInLine);
        }
        return Collections.unmodifiableMap(tally);
    }

    /**
     * Uses recursion to count the number of times a word appears in a line
     * @param word The word
     * @param tally the data structure to hold the records
     */
    private void doTally(String word, Map<String, Integer> tally, String[] wordsInLine) {
        word = cleanWord(word);
        if (tally.containsKey(word)) {
            int counter = 0;
            for (String w : wordsInLine) {
                w = cleanWord(w);
                if (word.equalsIgnoreCase(w)) {
                    counter++;
                }
            }
            tally.put(word, counter);
        } else {
            tally.put(word, 0);
            doTally(word, tally, wordsInLine);
        }
    }

    /**
     * For cleaning a word to ensure that 
     * @param word 
     * @return  
     */
    public String cleanWord(String word) {
        String[] delimiters = { "\n", " ", "  ", "\r", ".", "," };
        for (String del : delimiters) {
            word = StringUtils.remove(word, del).trim();
        }
        return word;
    }

}