LearnerZooKeeperServer has no option to disable JMX registrations. Curator has a test ZK server cluster. Due to the intricacies of JMX, the registrations cannot be easily undone. In order for the Curator Test cluster to be re-usable in a testing session, JavaAssist ugliness was necessary to make LearnerZooKeeperServer.registerJMX() and LearnerZooKeeperServer.unregisterJMX() NOPs.
I suggest a simple System property.