cityhubtopten.Top10Mapper.java Source code

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Here is the source code for cityhubtopten.Top10Mapper.java

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package cityhubtopten;

import java.io.IOException;
import java.util.Iterator;
import java.util.Map.Entry;
import java.util.TreeMap;
import org.apache.hadoop.io.DoubleWritable;
import org.apache.hadoop.io.LongWritable;
import org.apache.hadoop.io.NullWritable;
import org.apache.hadoop.io.Text;
import org.apache.hadoop.mapreduce.Mapper;

/**
 *
 * @author pranali
 */
public class Top10Mapper extends Mapper<LongWritable, Text, NullWritable, Text> {

    public static TreeMap<QualityOfLife, Text> ToRecordMap = new TreeMap<QualityOfLife, Text>();

    public void map(LongWritable key, Text value, Context context) throws IOException, InterruptedException {

        String line = value.toString();

        String[] tokens = line.split(",");
        if (line.contains("Quality of Life")) {
            return;
        }

        double quality = Double.parseDouble(tokens[6]);

        ToRecordMap.put(new QualityOfLife(quality), new Text(value));

        Iterator<Entry<QualityOfLife, Text>> iter = ToRecordMap.entrySet().iterator();

        Entry<QualityOfLife, Text> entry = null;

        while (ToRecordMap.size() > 10) {

            entry = iter.next();

            iter.remove();

        }

    }

    protected void cleanup(Context context) throws IOException, InterruptedException {

        for (Text t : ToRecordMap.values()) {

            context.write(NullWritable.get(), t);

        }

    }

}