code: protected Content getNavSummaryLink(ClassDoc cd, boolean link) {
          if (link) {
              return writer.getHyperLink(
                      SectionName.ANNOTATION_TYPE_OPTIONAL_ELEMENT_SUMMARY,
                      writer.getResource("doclet.navAnnotationTypeOptionalMember"));
          } else {
              return writer.getResource("doclet.navAnnotationTypeOptionalMember");
          }
      }
docs: {@inheritDoc}