In processMessage(), the message moves on to insertSequenceNumber(). If sequence numbering is enabled and is in Deferred Mode, the insertSequenceNumber method inserts the sequence number and call sendHL7Message(). The sendHL7Message method sends the HL7 V3 message to the external using the HL7 V3 adapter Message Library
The Collaboration receives the HL7 V3 ACK or NAK from the external using receiveHL7AckNak(). If an exception occurs due to incomplete data, and the adapter fails to read the data within the configured number of retries, the associated recourse action is taken. If the exception is due to no response, the associated recourse action is taken. If no exception occurs, the ACK or NAK message moves on to isAckMessage(), which validates the message to determine whether the message is an ACK or a NAK.
Next, the validateAckNak method unmarshals the message to the ACK Message Library in MCCI_IN000004UV01 Message Library for Immediate Mode and MCCI_IN000006UV01 Message Library for Deferred Mode.