code: public static String getModulePath( HttpServletRequest request, String requestURI )
      {
          return getModulePathForRelativeURI( getRelativeURI( request, requestURI, null ) );
      }
docs: Get the Struts module path for a URI.  This is the parent directory, relative to the web
  application root, of the file referenced by the URI.
  
  @param request the current HttpServletRequest.
  @param requestURI the URI for which to get the Struts module path.