code: protected void generateFrameFile() throws DocFileIOException {
          Content frame = getFrameDetails();
          HtmlTree body = new HtmlTree(HtmlTag.BODY);
          body.addAttr(HtmlAttr.ONLOAD, "loadFrames()");
          String topFilePath = configuration.topFile.getPath();
          String javaScriptRefresh = "\nif (targetPage == \"\" || targetPage == \"undefined\")\n" +
                  "     window.location.replace('" + topFilePath + "');\n";
          RawHtml scriptContent = new RawHtml(javaScriptRefresh.replace("\n", DocletConstants.NL));
          HtmlTree scriptTree = HtmlTree.SCRIPT();
          scriptTree.addContent(scriptContent);
          body.addContent(scriptTree);
          Content noScript = HtmlTree.NOSCRIPT(contents.noScriptMessage);
          body.addContent(noScript);
          if (configuration.allowTag(HtmlTag.MAIN)) {
              HtmlTree main = HtmlTree.MAIN(frame);
              body.addContent(main);
          } else {
              body.addContent(frame);
          }
          if (configuration.windowtitle.length() > 0) {
              printFramesDocument(configuration.windowtitle, configuration,
                      body);
          } else {
              printFramesDocument(configuration.getText("doclet.Generated_Docs_Untitled"),
                      configuration, body);
          }
      }
docs: Generate the constants in the "index.html" file. Print the frame details
  as well as warning if browser is not supporting the Html frames.
  @throws DocFileIOException if there is a problem generating the frame file