code: protected void addLinksForIndexes(Content contentTree) {
          for (Object ch : elements) {
              String unicode = ch.toString();
              contentTree.addContent(
                      getHyperLink(getNameForIndex(unicode),
                              new StringContent(unicode)));
              contentTree.addContent(getSpace());
          }
      }
docs: Add links for all the Index Files per unicode character.
  
  @param contentTree the content tree to which the links for indexes will be added