code: public Swagger2MarkupConfigBuilder withTagOrdering(Comparator<String> tagOrdering) {
          Validate.notNull(tagOrdering, "%s must not be null", "tagOrdering");
          config.tagOrderBy = OrderBy.CUSTOM;
          config.tagOrdering = tagOrdering;
          return this;
      }
docs: Specifies a custom comparator function to order tags.
  
  @param tagOrdering tag ordering
  @return this builder