Test #14 - 01. Olympics - Performance

import org.junit.Assert;
import org.junit.Before;
import org.junit.Test;

import java.util.ArrayList;
import java.util.List;

public class Test3 {

    private Olympics olympics;
    private InputGenerator inputGenerator;

    class InputGenerator {

        private final String[] COMPETITOR_NAMES = {"Ani", "Ani", "Ivo", "Asd", "Georgi", "Ivan", "Stamat", "Georgi", "Galin", "Mariika", "Ani", "Ani", "Ivo", "Asd", "Georgi", "Ivan", "Stamat", "Georgi", "Galin", "Mariika", "Ani", "Ani", "Ivo", "Asd", "Georgi", "Ivan", "Stamat", "Georgi", "Galin", "Mariika"};
        private final String[] COMPETITION_NAMES = {"Java", "VS", "SoftUniada", "CDiez", "Oracle", "JavaScript", "PHP", "Pascal", "C", "Swift", "Java", "VS", "SoftUniada", "CDiez", "Oracle", "JavaScript", "PHP", "Pascal", "C", "Swift", "Java", "VS", "SoftUniada", "CDiez", "Oracle", "JavaScript", "PHP", "Pascal", "C", "Swift", "Java", "VS", "SoftUniada", "CDiez", "Oracle", "JavaScript", "PHP", "Pascal", "C", "SwiftJava", "VS", "SoftUniada", "CDiez", "Oracle", "JavaScript", "PHP", "Pascal", "C", "SwiftJava", "VS", "SoftUniada", "CDiez", "Oracle", "JavaScript", "PHP", "Pascal", "C", "Swift"};


        List<Competitor> generateCompetitors(int count) {
            List<Competitor> competitors = new ArrayList<>();
            for (int i = 1; i <= count; i++) {
                competitors.add(new Competitor(i, COMPETITOR_NAMES[i % COMPETITOR_NAMES.length]));
            }
            return competitors;
        }

        List<Competition> generateCompetitions(int count) {
            List<Competition> competitions = new ArrayList<>();
            for (int i = 1; i <= count; i++) {
                competitions.add(new Competition(COMPETITION_NAMES[i % COMPETITION_NAMES.length], i, 5 + i));
            }
            return competitions;
        }
    }

    @Before
    public void setUp() {
        this.olympics = new OlympicsImpl();
        this.inputGenerator = new InputGenerator();
    }

    @Test
    public void addCompetitor_1_000_000_competitors_memory_usage() {

        List<Competitor> competitors = this.inputGenerator.generateCompetitors(500000);

        Runtime runtime = Runtime.getRuntime();
        long usedMemoryBefore = runtime.totalMemory() - runtime.freeMemory();

        for (Competitor competitor : competitors) {
            this.olympics.addCompetitor(competitor.getId(), competitor.getName());
        }
        long usedMemoryInMB = (Math.abs(runtime.totalMemory() - runtime.freeMemory() - usedMemoryBefore)) / (1024 * 1024);

        Assert.assertTrue(usedMemoryInMB > 50 && usedMemoryInMB < 120);

    }
}