code: public static void generate(ConfigurationImpl configuration) {
          HelpWriter helpgen;
          DocPath filename = DocPath.empty;
          try {
              filename = DocPaths.HELP_DOC;
              helpgen = new HelpWriter(configuration, filename);
              helpgen.generateHelpFile();
              helpgen.close();
          } catch (IOException exc) {
              configuration.standardmessage.error(
                          "doclet.exception_encountered",
                          exc.toString(), filename);
              throw new DocletAbortException(exc);
          }
      }
docs: Construct the HelpWriter object and then use it to generate the help
  file. The name of the generated file is "help-doc.html". The help file
  will get generated if and only if "-helpfile" and "-nohelp" is not used
  on the command line.
  @throws DocletAbortException