Main.java Source code

Introduction

Here is the source code for Main.java

Source

import java.time.LocalDate;
import java.time.Month;
import java.util.Arrays;
import java.util.List;
import java.util.Map;
import java.util.stream.Collectors;

public class Main {
    public static void main(String[] args) {
        Map personsByGenderAndDobMonth = Employee.persons().stream().collect(
                Collectors.groupingBy(Employee::getGender, Collectors.groupingBy(p -> p.getDob().getMonth(),
                        Collectors.mapping(Employee::getName, Collectors.joining(", ")))));

        System.out.println(personsByGenderAndDobMonth);
    }
}

class Employee {
    public static enum Gender {
        MALE, FEMALE
    }

    private long id;
    private String name;
    private Gender gender;
    private LocalDate dob;
    private double income;

    public Employee(long id, String name, Gender gender, LocalDate dob, double income) {
        this.id = id;
        this.name = name;
        this.gender = gender;
        this.dob = dob;
        this.income = income;
    }

    public String getName() {
        return name;
    }

    public Gender getGender() {
        return gender;
    }

    public void setGender(Gender gender) {
        this.gender = gender;
    }

    public LocalDate getDob() {
        return dob;
    }

    public static List<Employee> persons() {
        Employee p1 = new Employee(1, "Jake", Gender.MALE, LocalDate.of(1971, Month.JANUARY, 1), 2343.0);
        Employee p2 = new Employee(2, "Jack", Gender.MALE, LocalDate.of(1972, Month.JULY, 21), 7100.0);
        Employee p3 = new Employee(3, "Jane", Gender.FEMALE, LocalDate.of(1973, Month.MAY, 29), 5455.0);
        Employee p4 = new Employee(4, "Jode", Gender.MALE, LocalDate.of(1974, Month.OCTOBER, 16), 1800.0);
        Employee p5 = new Employee(5, "Jeny", Gender.FEMALE, LocalDate.of(1975, Month.DECEMBER, 13), 1234.0);
        Employee p6 = new Employee(6, "Jason", Gender.MALE, LocalDate.of(1976, Month.JUNE, 9), 3211.0);

        List<Employee> persons = Arrays.asList(p1, p2, p3, p4, p5, p6);

        return persons;
    }
}