ChangelogReader Internal Contract

ChangelogReader is the internal contract for changelog readers that…FIXME

Table 1. ChangelogReader Contract
Method	Description
`register`	`void register(StateRestorer restorer)` Registers a StateRestorer (for a changelog partition) Used exclusively when `ProcessorStateManager` is requested to register a persistent state store (with an underlying changelog topic)
`reset`	`void reset()` Used exclusively when `TaskManager` is requested to suspend all (active and standby) tasks and state (when `RebalanceListener` is requested to handle onPartitionsRevoked event (at the beginning of consumer rebalance))
`restore`	`Collection<TopicPartition> restore( RestoringTasks active)` Restores logging-enabled state stores using the RestoringTasks Used exclusively when `TaskManager` is requested to updateNewAndRestoringTasks (when the owning `StreamThread` is requested to poll records once and process them using active stream tasks while running the main record processing loop)
`restoredOffsets`	`Map<TopicPartition, Long> restoredOffsets()` Restores offsets (for persistent state stores) Used exclusively when `ProcessorStateManager` is requested to checkpoint offsets

Note	StoreChangelogReader is the default and only known implementation of the ChangelogReader Contract in Kafka Streams.

ChangelogReader