code: protected HtmlTree getClassUseHeader() {
          String cltype = configuration.getText(classdoc.isInterface()?
              "doclet.Interface":"doclet.Class");
          String clname = classdoc.qualifiedName();
          String title = configuration.getText("doclet.Window_ClassUse_Header",
                  cltype, clname);
          HtmlTree bodyTree = getBody(true, getWindowTitle(title));
          HtmlTree htmlTree = (configuration.allowTag(HtmlTag.HEADER))
                  ? HtmlTree.HEADER()
                  : bodyTree;
          addTop(htmlTree);
          addNavLinks(true, htmlTree);
          if (configuration.allowTag(HtmlTag.HEADER)) {
              bodyTree.addContent(htmlTree);
          }
          ContentBuilder headContent = new ContentBuilder();
          headContent.addContent(getResource("doclet.ClassUse_Title", cltype));
          headContent.addContent(new HtmlTree(HtmlTag.BR));
          headContent.addContent(clname);
          Content heading = HtmlTree.HEADING(HtmlConstants.CLASS_PAGE_HEADING,
                  true, HtmlStyle.title, headContent);
          Content div = HtmlTree.DIV(HtmlStyle.header, heading);
          if (configuration.allowTag(HtmlTag.MAIN)) {
              mainTree.addContent(div);
          } else {
              bodyTree.addContent(div);
          }
          return bodyTree;
      }
docs: Get the header for the class use Listing.
  
  @return a content tree representing the class use header