code: public List<ClassDoc> allSubs(ClassDoc cd, boolean isEnum) {
          List<ClassDoc> list = subs(cd, isEnum);
          for (int i = 0; i < list.size(); i++) {
              cd = list.get(i);
              List<ClassDoc> tlist = subs(cd, isEnum);
              for (int j = 0; j < tlist.size(); j++) {
                  ClassDoc tcd = tlist.get(j);
                  if (!list.contains(tcd)) {
                      list.add(tcd);
                  }
              }
          }
          Collections.sort(list);
          return list;
      }
docs: Return a list of all direct or indirect, sub-classes and subinterfaces
  of the ClassDoc argument.
  
  @param cd ClassDoc whose sub-classes or sub-interfaces are requested.
  @param isEnum true if the subclasses should be forced to come from the
  enum tree.