MapReduce/Mapper at master · hadooping/MapReduce · GitHub

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Enter file contents hereimport java.io.IOException;

import org.apache.hadoop.io.IntWritable;
import org.apache.hadoop.io.LongWritable;
import org.apache.hadoop.io.Text;
import org.apache.hadoop.mapred.MapReduceBase;
import org.apache.hadoop.mapred.Mapper;
import org.apache.hadoop.mapred.OutputCollector;
import org.apache.hadoop.mapred.Reporter;

public class MaxTemperatureMapper extends MapReduceBase implements
		Mapper<LongWritable, Text, Text, IntWritable> {

	public static final int MISSING = 9999;
	@Override
	public void map(LongWritable key, Text value,
			OutputCollector<Text, IntWritable> output, Reporter reporter)
			throws IOException {


	String line = value.toString();
	String year = line.substring(15,19);
	int airTemperature = 0;
		if (line.charAt(87) == '+') {
			airTemperature = Integer.parseInt(line.substring(88,92));
		} else {
			airTemperature = Integer.parseInt(line.substring(87,92));
		}

		String quality = line.substring(92,93);
		if(airTemperature != MISSING && quality.matches("[01459]")){
			output.collect(new Text(year), new IntWritable(airTemperature));
		}
	}

}