How to get the age, and set stuff for people... will need for future projects

PersonData

package com.company;

import java.time.LocalDate;
import java.util.Date;
import java.util.Random;

public class Person {

    Random rand = new Random();
    private int age;
    private boolean isAdult;

    public Person(byte day, byte month, int year) {
        this.age = LocalDate.now().minusYears(year).minusMonths(month).minusDays(day).getYear();
    }

    public Person(int age) {
        this.age = age;
        this.isAdult = age >= 18;
    }

    public int getAge() {
        return age;
    }

    public enum STAGE {
        ADULT,
        KID
    }

    public enum Sex {
        MALE,
        FEMALE
    }

    public static Person createNothing() {
        return new Person(-1);
    }

    public static Person create(int age) {
        return new Person(age);
    }

    public static Person create(byte day, byte month, int year) {
        return new Person(day, month, year);
    }

    public static void main(String[] args) {
        System.out.println(Person.create((byte) 14, (byte) 9, 2001).getAge());
    }
}