public boolean equals(Object o) {
        if (this == o) return true;
        if (!(o instanceof Person)) return false;

        Person person = (Person) o;

        if (id != person.id) return false;
        if (name != null ? !name.equals(person.name) : person.name != null) return false;
        if (surname != null ? !surname.equals(person.surname) : person.surname != null) return false;

        return true;
    }