code: protected File getScriptUriAsFile(HttpServletRequest request) {
          String uri = getScriptUri(request);
          String real = servletContext.getRealPath(uri);
          if (real == null) {
              return null;
          }
          return new File(real).getAbsoluteFile();
      }
docs: Parses the http request for the real script or template source file.
  
  @param request
  the http request to analyze
  @return a file object using an absolute file path name, or <code>null</code> if the
  servlet container cannot translate the virtual path to a real
  path for any reason (such as when the content is being made
  available from a .war archive).