docs: @SuppressWarnings("unchecked")
  	static public Map<String, Object> getParameters(ServletRequest request){
      	Map<String, Object> params = (Map<String, Object>) request.getAttribute(TEMPLATE_PARAMETER_MAP);
      	if (params == null){							// no need to check thread-safe?
      		params = new HashMap<String, Object>();
      		request.setAttribute(TEMPLATE_PARAMETER_MAP, params);
      	}
      	return params;
      }