Implement a Strict At Most Once Delivery Policy
20.3.Ă‚Â Guarantees of Non Transactional Acknowledgements If you are acknowledging the delivery of a message at the client side using a non transacted session, HornetQ can be configured to block the call to acknowledge until the acknowledge has definitely reached the server, and a response has been sent back to the client. This is configured with the parameter BlockOnAcknowledge. If this is set to true then all calls to acknowledge on non transacted sessions will block until the acknowledge has reached the server, and a response has been sent back. You might want to set this to true if you want to implement a strict at most once delivery policy. The default value is false