Handling poison messages in ASF

When we use Application Server Facilities (ASF), the ConnectionConsumer, rather than the MessageConsumer, processes poison messages. The ConnectionConsumer requeues messages according to the BackoutThreshold and BackoutRequeueQName properties of the queue.

When an application uses ConnectionConsumers, the circumstances in which a message is backed out depend on the session that the application server provides:

• When the session is non-transacted, with AUTO_ACKNOWLEDGE or DUPS_OK_ACKNOWLEDGE, a message is backed out only after a system error, or if the application terminates unexpectedly.
• When the session is non-transacted with CLIENT_ACKNOWLEDGE, unacknowledged messages can be backed out by the application server calling Session.recover().

  Typically, the client implementation of MessageListener or the application server calls Message.acknowledge(). Message.acknowledge() acknowledges all messages delivered on the session so far.

• When the session is transacted, unacknowledged messages can be backed out by the application server calling Session.rollback().