FriendsReducer.java Source code

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Here is the source code for FriendsReducer.java

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/*
 * 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.hadoop.examples.anagrams;

import java.io.IOException;
import java.util.Iterator;
import java.util.StringTokenizer;
import java.util.List;
import java.util.ArrayList;
import java.util.Arrays;
import org.apache.hadoop.io.Text;
import org.apache.hadoop.mapred.MapReduceBase;
import org.apache.hadoop.mapred.OutputCollector;
import org.apache.hadoop.mapred.Reducer;
import org.apache.hadoop.mapred.Reporter;

/**
 * The Anagram reducer class groups the values of the sorted keys that came in and 
 * checks to see if the values iterator contains more than one word. if the values 
 * contain more than one word we have spotted a anagram.
 * @author subbu
 *
 */

public class FriendsReducer extends MapReduceBase implements Reducer<Text, Text, Text, Text> {

    private Text outputKey = new Text();
    private Text outputValue = new Text();

    public void reduce(Text anagramKey, Iterator<Text> anagramValues, OutputCollector<Text, Text> results,
            Reporter reporter) throws IOException {
        String output = "";
        List<String> values1 = Arrays.asList(anagramValues.next().toString().split(","));
        String[] values2 = anagramValues.next().toString().split(",");
        List<String> r = new ArrayList<String>();
        for (String v2 : values2) {
            if (values1.contains(v2))
                r.add(v2);
        }

        //StringTokenizer outputTokenizer = new StringTokenizer(output,"~");
        /*      if(outputTokenizer.countTokens()>=2)
              {*/
        //   output = output.replace("~", ",");
        outputKey.set(anagramKey.toString());
        outputValue.set(String.join(",", r));
        results.collect(outputKey, outputValue);
        //}
    }

}