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If any of these errors are detected, the StreamsPartitionAssignor will immediately "fail" the rebalance and retry it by scheduling an immediate followup rebalance. If this occurs, the input assignment will be used as the new assignment, and the corresponding error will be returned from the #onAssignmentComputed APIthrow an exception after returning the error code via the #onAssignmentComputed callback. This error will be bubbled up through the StreamThread to the uncaught exception handler where the user can choose how to react from there, same as any other exception
Consumer Assignments
One major decision in this KIP was whether to encompass the assignment of tasks to consumers/threads within each KafkaStreams client, or to leave that up to the StreamsPartitionAssignor and only carve out the KafkaStreams-level assignment for pluggability. Ultimately we decided on the latter, for several reasons:
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