docs: private void handleSpecialization(final String localName, final String classAttr) {
          if (classAttr == null) {
          } else if (TOPIC_INDEXTERM.matches(classAttr)) {
              // add the element name to the indexterm specialization element
              // list if it does not already exist in that list.
              if (!indexTermSpecList.contains(localName)) {
                  indexTermSpecList.add(localName);
              }
          } else if (INDEXING_D_INDEX_SEE_ALSO.matches(classAttr)) {
              // add the element name to the index-see-also specialization element
              // list if it does not already exist in that list.
              if (!indexSeeAlsoSpecList.contains(localName)) {
                  indexSeeAlsoSpecList.add(localName);
              }
          } else if (INDEXING_D_INDEX_SEE.matches(classAttr)) {
              // add the element name to the index-see specialization element
              // list if it does not already exist in that list.
              if (!indexSeeSpecList.contains(localName)) {
                  indexSeeSpecList.add(localName);
              }
          } else if (INDEXING_D_INDEX_SORT_AS.matches(classAttr)) {
              // add the element name to the index-sort-as specialization element
              // list if it does not already exist in that list.
              if (!indexSortAsSpecList.contains(localName)) {
                  indexSortAsSpecList.add(localName);
              }
          } else if (TOPIC_TOPIC.matches(classAttr)) {
              //add the element name to the topic specialization element
              // list if it does not already exist in that list.
              if (!topicSpecList.contains(localName)) {
                  topicSpecList.add(localName);
              }
          } else if (TOPIC_TITLE.matches(classAttr)) {
              //add the element name to the title specailization element list
              // if it does not exist in that list.
              if (!titleSpecList.contains(localName)) {
                  titleSpecList.add(localName);
              }
          }
      }