code: protected SortOrder convertSortOrder() {
          final String sortOrder = getSortOrder();
          if (sortOrder == null) {
              return SortOrder.UNSORTED;
          }
          else {
              final SortOrder result = SortOrder.valueOf(sortOrder.toUpperCase(Locale.ENGLISH));
              return result;
          }
      }
docs: Convert to PF SortOrder enum since we are leveraging PF sorting code.
  
  @return