/// <summary>
        /// Serializes object into a string containing all of its public variables.
        /// </summary>
        /// <returns>Serialized object as a string.</returns>
        public override string Serialize()
        {
            var nextID   = NextID?.ToString() ?? "-";
            var outPort  = OutPort?.ToString() ?? "-";
            var outLabel = OutLabel?.ToString() ?? "-";

            return($"{ID} {Action} {outLabel} {outPort} {nextID}");
        }
        /// <summary>
        /// Converts a whole NHLFE entry to a string; used in logs.
        /// </summary>
        /// <returns>Converted NHLFE entry to a string.</returns>
        public override string ToString()
        {
            var nextID   = NextID?.ToString() ?? "-";
            var outPort  = OutPort?.ToString() ?? "-";
            var outLabel = OutLabel?.ToString() ?? "-";

            return($"{nameof(ID)}: {ID}, {nameof(Action)}: {Action}, {nameof(OutLabel)}: {outLabel}, {nameof(OutPort)}: {outPort}, {nameof(NextID)}: {nextID}");
        }