code: public boolean handleWelcomeRedirect( FileRequestContext context ) throws IOException {
      if( context.file.isFile() && context.file.getName().equals("index.html")) {
        resolveContentType(context);
        String location = context.path.replaceFirst("/index.html\\Z", "");
        if( location.isEmpty() ) location = "/";
        if( context.request.getQueryString() != null ) location = location + "?" + context.request.getQueryString();
        sendPermanentRedirect(context, location);
        return true;
      }
      return false;
    }
docs: Forces requests for index files to not use the file name.
  
  @param context
  @return true if the request was handled, false otherwise.
  @throws IOException