code: public String getRequestParam(HttpServletRequest request, String param, String defaultValue)
      {
          String value = request.getParameter(servicePid + '.' + param);
          if ((value == null) && (properties != null))
              value = properties.get(servicePid + '.' + param);
          if (value == null)
              value = request.getParameter(param);
          if ((value == null) && (properties != null))
              value = properties.get(param);
          if (value == null)
                  value = defaultValue;
          return value;
      }
docs: Get this param from the request or from the servlet's properties.
  @param request
  @param param
  @param defaultValue
  @return