com.airline.analytics.AirlineDelayAnalytics.java Source code

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Here is the source code for com.airline.analytics.AirlineDelayAnalytics.java

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package com.airline.analytics;

import java.io.IOException;

import org.apache.hadoop.conf.Configured;
import org.apache.hadoop.fs.Path;
import org.apache.hadoop.io.IntWritable;
import org.apache.hadoop.io.Text;
import org.apache.hadoop.mapreduce.Job;
import org.apache.hadoop.mapreduce.Mapper;
import org.apache.hadoop.mapreduce.Reducer;
import org.apache.hadoop.mapreduce.lib.input.FileInputFormat;
import org.apache.hadoop.mapreduce.lib.output.FileOutputFormat;
import org.apache.hadoop.util.Tool;
import org.apache.hadoop.util.ToolRunner;

/**
 * @author dhamodharan.ra
 */
public class AirlineDelayAnalytics extends Configured implements Tool {

    public static class AirlineMapper extends Mapper<Object, Text, IntWritable, IntWritable> {

        private IntWritable flightNumber = new IntWritable();
        private IntWritable delay = new IntWritable();

        private String splitBy = ",";

        @Override
        public void map(Object key, Text value, Context context) throws IOException, InterruptedException {

            String[] column = value.toString().split(splitBy);

            flightNumber.set(Integer.parseInt(column[9]));

            int actualElapsedTime = column[11].equals("NA") ? 0 : Integer.parseInt(column[11]);
            int csrElapsedTime = column[11].equals("NA") ? 0 : Integer.parseInt(column[12]);
            int arrivalDelay = column[11].equals("NA") ? 0 : Integer.parseInt(column[14]);
            int depatureDelay = column[11].equals("NA") ? 0 : Integer.parseInt(column[15]);

            int actualDelay = arrivalDelay + depatureDelay + (actualElapsedTime - csrElapsedTime);

            delay.set(actualDelay);

            context.write(flightNumber, delay);
        }
    }

    public static class AirlineReducer extends Reducer<IntWritable, IntWritable, IntWritable, Text> {

        private Text result = new Text();

        @Override
        public void reduce(IntWritable key, Iterable<IntWritable> values, Context context)
                throws IOException, InterruptedException {

            int delay = 0;
            int minDelay = 100000;
            int maxDelay = 0;
            int count = 0;

            for (IntWritable val : values) {

                delay += val.get();

                if (val.get() < minDelay) {
                    minDelay = val.get();
                }

                if (val.get() > maxDelay) {
                    maxDelay = val.get();
                }
                count++;
            }

            long averageDelay = delay / count;

            if (averageDelay < 0) {
                averageDelay = 0;
            }

            if (minDelay < 0) {
                minDelay = 0;
            }

            result.set(averageDelay + ", " + minDelay + ", " + maxDelay);

            context.write(key, result);
        }
    }

    @Override
    public int run(String[] strings) throws Exception {

        Job job = Job.getInstance(getConf(), "Hadoop Airline Delay Analytics");

        job.setJarByClass(AirlineDelayAnalytics.class);

        job.setMapperClass(AirlineMapper.class);
        // job.setCombinerClass(AirlineReducer.class);
        job.setReducerClass(AirlineReducer.class);

        job.setMapOutputKeyClass(IntWritable.class);
        job.setMapOutputValueClass(IntWritable.class);

        job.setOutputKeyClass(IntWritable.class);
        job.setOutputValueClass(Text.class);

        FileInputFormat.addInputPath(job, new Path(strings[0]));
        FileOutputFormat.setOutputPath(job, new Path(strings[1]));

        return job.waitForCompletion(true) ? 0 : 1;
    }

    public static void main(String[] args) throws Exception {
        int exitCode = ToolRunner.run(new AirlineDelayAnalytics(), args);
        System.exit(exitCode);
    }
}