Interface Query<R>

Type Parameters:
R - The type of the result returned by this query.
All Known Implementing Classes:
KeyQuery, RangeQuery, WindowKeyQuery, WindowRangeQuery

public interface Query<R>
Marker interface that all interactive queries must implement (see KafkaStreams.query(StateQueryRequest)).

You can find all available queries by searching for classes implementing this interface.

Kafka Streams will pass unknown query types straight through into the bytes stores, so callers can add custom queries by implementing this interface and providing custom stores that handle them (via StoreSuppliers.

See KIP-796 ( for more details.