krossbow-stomp-core/org.hildan.krossbow.stomp.headers/StompMessageHeadersBuilder/ack

ack

abstract override var ack: String?

The value to use for a corresponding ACK or NACK frame.

If the message is received from a subscription that requires explicit acknowledgment (either AckMode.CLIENT or AckMode.CLIENT_INDIVIDUAL), then the MESSAGE frame MUST also contain an ack header with an arbitrary value. This header will be used to relate the message to a subsequent ACK or NACK frame.