org.apache.kafka.streams.state

Interface WindowBytesStoreSupplier

All Superinterfaces:

StoreSupplier<WindowStore<org.apache.kafka.common.utils.Bytes,byte[]>>

public interface WindowBytesStoreSupplier
extends StoreSupplier<WindowStore<org.apache.kafka.common.utils.Bytes,byte[]>>

A store supplier that can be used to create one or more WindowStore instances of type <Byte, byte[]>. For any stores implementing the WindowStore interface, null value bytes are considered as "not exist". This means: 1. Null value bytes in put operations should be treated as delete. 2. Null value bytes should never be returned in range query results.

Method Summary

Modifier and Type	Method and Description
boolean	retainDuplicates() Whether or not this store is retaining duplicate keys.
long	retentionPeriod() The time period for which the WindowStore will retain historic data.
int	segments() The number of segments the store has.
long	windowSize() The size of the windows any store created from this supplier is creating.

Methods inherited from interface org.apache.kafka.streams.state.StoreSupplier

get, metricsScope, name

Method Detail

segments

int segments()

The number of segments the store has. If your store is segmented then this should be the number of segments in the underlying store. It is also used to reduce the amount of data that is scanned when caching is enabled.

Returns:

number of segments

windowSize

long windowSize()

The size of the windows any store created from this supplier is creating.

Returns:

window size

retainDuplicates

boolean retainDuplicates()

Whether or not this store is retaining duplicate keys. Usually only true if the store is being used for joins. Note this should return false if caching is enabled.

Returns:

true if duplicates should be retained

retentionPeriod

long retentionPeriod()

The time period for which the WindowStore will retain historic data.

Returns:

retentionPeriod