What is the purpose of RabbitMQ AMQP Java client shutdown handlers?

Question

The RabbitMQ documentation presents how to add a shutdown listener and when the listener is called but I fail to see on what purpose the handler is for. Seems that all the Java examples (including https://github.com/rabbitmq/rabbitmq-tutorials) out there ignore shutdown handlers. In which cases should I prefer shutdown listener over simply catching ShutdownSignalException (and IOException) exception ?

Another puzzling issue is that where the control flow goes when the handler has finished.

Potentially relevant related SO questions:

• What is the best way to safely end a java application with running RabbitMQ consumers
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Answer 1

The main use of a ShutdownListener i've seen is to do automatic reconnection. You listen for a shutdown, and when it happens, try to reconnect.

For example, this is the basis of rabbitmq-ha-client, where it is done in HaConnectionFactory.HaShutdownListener.