K- type of key
N- type of namespace
S- type of state
CopyOnWriteStateTableand has a role in operator state checkpointing. Besides holding the
CopyOnWriteStateTables internal entries at the time of the snapshot, this class is also responsible for preparing and writing the state in the process of checkpointing.
IMPORTANT: Please notice that snapshot integrity of entries in this class rely on proper copy-on-write semantics
CopyOnWriteStateTable that created the snapshot object, but all objects in this snapshot must be considered
as READ-ONLY!. The reason is that the objects held by this class may or may not be deep copies of original objects
that may still used in the
CopyOnWriteStateTable. This depends for each entry on whether or not it was subject to
copy-on-write operations by the
CopyOnWriteStateTable. Phrased differently: the
copy-on-write isolation for this snapshot, but this snapshot does not isolate modifications from the
|Modifier and Type||Method and Description|
Optional hook to release resources for this snapshot at the end of its lifecycle.
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