validate the message . throws an exception if the message is invalid . concode_field_sep int mId concode_field_sep void encode concode_elem_sep ByteToMessageDecoder createFrameDecoder concode_elem_sep Type getType concode_elem_sep DataBuffer getPayloadDataBuffer concode_elem_sep int getId concode_elem_sep RPCMessage decodeMessage concode_elem_sep boolean hasPayload concode_elem_sep Type decode concode_elem_sep int getEncodedLength