Common Exception Types

You may see the following exceptions in any Hazelcast operation when the following situations occur:

  • HazelcastInstanceNotActiveException: Thrown when HazelcastInstance is not active (already shutdown or being shutdown) during an invocation.

  • HazelcastOverloadException: Thrown when the system will not handle more load due to an overload. This exception is thrown when back pressure is enabled.

  • DistributedObjectDestroyedException: Thrown when an already destroyed DistributedObject (IMap, IQueue, etc.) is accessed and when a method call is done over a destroyed object.

  • MemberLeftException: Thrown when a member leaves during an invocation or execution.

Hazelcast also throws the following exceptions in the cases of overall system problems such as networking issues and long pauses:

  • PartitionMigratingException: Thrown when an operation is executed on a partition, but that partition is currently being moved around.

  • TargetNotMemberException: Thrown when an operation is sent to a machine that is not a member of the cluster.

  • CallerNotMemberException: Thrown when an operation was sent by a machine which is not a member in the cluster when the operation is executed.

  • WrongTargetException: Thrown when an operation is executed on the wrong machine, mostly because the partition that operation belongs to is already moved to some other member.