Major Description
JE throws an asynchronous exception (RolllbackException) to indicate that, owing to the use of weak durability options a node that is trying to rejoin the group has transactions that do not match those of the current master, and it must rollback one or more transactions in order to join.
This condition can't occur in use of the group with default quorum options, but if a user were to use node priority zero, electable group override or designate primary (options that all weaken durability), creates the situation were nodes can diverge (split brain).
In the case where JE detects this, it delivers a RollbackException asynchronously shortly after environment creation and requires that the environment restarts so the diverged transactions can be dropped.
Java Broker should catch this exception, log it and organise for the environment to restart.