How to build an hierarchy tree of categories in java using enums or any other way?

Question

Assuming that we have a set of categories: categories={A,B}. Let\'s assume more that A consists of subcategories: {A1,A2,A3} and B consists of subcategories: {B1,B2}.In addi

Answer 1

Probably an implementation of this:

public interface Category {
    String getName();
    Category getParent();
    List getSiblings();
    List getChildren();
    List getDescendants();
    void addChild(Category category);
    void addChildren(List categories);
}