public class NicknameDatabase<F> {

    public void printNickname(Person<F> person) {
        Person<F>.Nickname nickname = person.getNickname();
        System.out.println(nickname);
    }

    static class Person<E> {
        private Nickname nickname;

        public Nickname getNickname() {
            return nickname;
        }

        public void setNickname(Nickname nickname) {
            this.nickname = nickname;
        }

        class Nickname {
            private String name;
            private boolean insulting;
        }
    }
}