Java 8 version of tourist example (http://blog.dhananjaynene.com/2018/01/analysing-tourism-data-with-kotlin)

Tourist.java

package com.rohankar.tourist;

import io.vavr.Tuple3;
import io.vavr.collection.Stream;

import java.io.File;
import java.io.IOException;
import java.nio.file.Files;
import java.util.Arrays;
import java.util.List;

import static java.util.Comparator.naturalOrder;
import static java.util.stream.Collectors.toList;

/**
 * Java 8 (using Vavr) version of original Tourist example written in Kotlin.
 * See: http://blog.dhananjaynene.com/2018/01/analysing-tourism-data-with-kotlin
 *
 * @author Sagar Rohankar
 */
public class Tourist {

    public static void main(String[] args) throws IOException {

        Stream<String> strings = Stream.ofAll(Files.readAllLines(new File("tourists-to-india.csv").toPath()));

        strings
                .drop(1) // csv header
                .dropRight(1) // total row
                .map(row -> row.split(","))
                .map(arr -> {
                    List<Integer> visitors = Arrays.stream(Arrays.copyOfRange(arr, 2, arr.length))
                            .mapToInt(Integer::parseInt)
                            .boxed()
                            .collect(toList());
                    return new Tuple3<>(arr[0], arr[1], visitors); // <Country, Continent, Visitors>
                })
                .groupBy(countryContinentVisitors -> countryContinentVisitors._2) // by Continent
                .mapValues(tuple -> {
                    int tourist2001 = tuple.map(Tuple3::_3)
                            .map(l -> l.get(0))
                            .sum()
                            .intValue();
                    int tourist2015 = tuple.map(Tuple3::_3)
                            .map(l -> l.get(14))
                            .sum()
                            .intValue();

                    double pctGrowth = (tourist2015 - tourist2001) * 100 / tourist2001;

                    String maxCountry = tuple
                            .sortBy(t -> t._3()
                                    .stream()
                                    .mapToInt(Integer::intValue)
                                    .sum())
                            .last()
                            ._1;

                    return new Tuple3<>(tourist2015, pctGrowth, maxCountry);
                })
                .map(tuple -> tuple._2) // skip tuple._1 which is continent
                .sorted(naturalOrder())
                .forEach(System.out::println);
    }

}