/// <summary>
        /// Customized length calculator of ApplicationData, called by Channel.
        /// This method's name is written in ApplicationData's Size attribute.
        /// </summary>
        /// <param name="context">Channel's context.</param>
        /// <returns>ApplicationData's length.</returns>
        // this method is called by Channel.
        internal static int CalculateApplicationDataLength(IEvaluationContext context)
        {
            _ACE_HEADER header = (_ACE_HEADER)context.Variables["Header"];
            _SID        sid    = (_SID)context.Variables["Sid"];

            return(DtypUtility.CalculateApplicationDataLength(header, sid));
        }