Kafka Word Count

package com.fidelity.service;

import java.util.Arrays;
import java.util.Map;
import java.util.HashMap;
import java.util.Scanner;
import java.util.regex.Pattern;

import org.springframework.boot.CommandLineRunner;
import org.springframework.stereotype.Component;
import scala.Tuple2;

import org.apache.spark.SparkConf;
import org.apache.spark.api.java.function.FlatMapFunction;
import org.apache.spark.api.java.function.Function;
import org.apache.spark.api.java.function.Function2;
import org.apache.spark.api.java.function.PairFunction;
import org.apache.spark.streaming.Duration;
import org.apache.spark.streaming.api.java.JavaDStream;
import org.apache.spark.streaming.api.java.JavaPairDStream;
import org.apache.spark.streaming.api.java.JavaPairReceiverInputDStream;
import org.apache.spark.streaming.api.java.JavaStreamingContext;
import org.apache.spark.streaming.kafka.KafkaUtils;

/**
 * Consumes messages from one or more topics in Kafka and does wordcount.
 *
 * Usage: JavaKafkaWordCount <zkQuorum> <group> <topics> <numThreads>
 *   <zkQuorum> is a list of one or more zookeeper servers that make quorum
 *   <group> is the name of kafka consumer group
 *   <topics> is a list of one or more kafka topics to consume from
 *   <numThreads> is the number of threads the kafka consumer should use
 *
 * To run this example:
 *   `$ bin/run-example org.apache.spark.examples.streaming.JavaKafkaWordCount zoo01,zoo02, \
 *    zoo03 my-consumer-group topic1,topic2 1`
 */


public final class JavaKafkaWordCount{
    private static final Pattern SPACE = Pattern.compile(" ");

    private JavaKafkaWordCount() {
    }


    public static void main(String... strings) throws Exception {

        System.out.println("********* ME CHALA ******");
        SparkConf sparkConf = new SparkConf().setAppName("JavaKafkaWordCount").setMaster("local[2]").set("spark.executor.memory","1g");
        // Create the context with 2 seconds batch size
        JavaStreamingContext jssc = new JavaStreamingContext(sparkConf, new Duration(2000));

        int numThreads = 2;
        Map<String, Integer> topicMap = new HashMap<>();
        topicMap.put("test",2);


        JavaPairReceiverInputDStream<String, String> messages =
                KafkaUtils.createStream(jssc, "localhost", "test-group", topicMap);

        JavaDStream<String> lines = messages.map(new Function<Tuple2<String, String>, String>() {
            @Override
            public String call(Tuple2<String, String> tuple2) {
                return tuple2._2();
            }
        });

        JavaDStream<String> words = lines.flatMap(new FlatMapFunction<String, String>() {
            @Override
            public Iterable<String> call(String s) throws Exception {
                return (Iterable<String>) Arrays.asList(SPACE.split(s)).iterator();
            }
        });

        JavaPairDStream<String, Integer> wordCounts = words.mapToPair(
                new PairFunction<String, String, Integer>() {
                    @Override
                    public Tuple2<String, Integer> call(String s) {
                        return new Tuple2<>(s, 1);
                    }
                }).reduceByKey(new Function2<Integer, Integer, Integer>() {
            @Override
            public Integer call(Integer i1, Integer i2) {
                return i1 + i2;
            }
        });

        wordCounts.print();
        jssc.start();
        jssc.awaitTermination();

    }

}