import java.util.Objects; import java.time.LocalDate; public class Human { String name; String surName; int age; LocalDate dateOfBirth; int iin; public Human(String name, String surName, int age, LocalDate dateOfBirth, int iin) { this.name = name; this.surName = surName; this.age = age; this.dateOfBirth = dateOfBirth; this.iin = iin; } @Override public boolean equals(Object o) { if (this == o) return true; if (o == null || getClass() != o.getClass()) return false; Human human = (Human) o; return iin == human.iin; } @Override public int hashCode() { return Objects.hash(iin); // хэш тоже строим по IIN } } public class Main { public static void main(String[] args) { Human h1 = new Human("Yerkebulan", "Orda", 30, LocalDate.of(1995, 5, 5), 123456789); Human h2 = new Human("Yerkebulan", "Orda", 30, LocalDate.of(1995, 5, 5), 123456789); Human h3 = new Human("Almas", "Omarov", 22, LocalDate.of(2003, 3, 3), 987654321); System.out.println("h1.equals(h2): " + h1.equals(h2)); System.out.println("h1.equals(h3): " + h1.equals(h3)); } }