org.apache.kafka.streams.query

Class StateQueryResult<R>

java.lang.Object

org.apache.kafka.streams.query.StateQueryResult<R>

Type Parameters:

R - The type of the query result.

@InterfaceStability.Evolving
public class StateQueryResult<R>
extends Object

The response object for interactive queries. This wraps the individual partition results, as well as metadata relating to the result as a whole.

Constructor Summary

Constructors

Constructor and Description
StateQueryResult()

Method Summary

Modifier and Type	Method and Description
void	addResult(int partition, QueryResult<R> r) Set the result for a partitioned store query.
QueryResult<R>	getGlobalResult() The query's result for global store queries.
QueryResult<R>	getOnlyPartitionResult() For queries that are expected to match records in only one partition, returns the result.
Map<Integer,QueryResult<R>>	getPartitionResults() The query's result for each partition that executed the query.
Position	getPosition() The position of the state store at the moment it executed the query.
void	setGlobalResult(QueryResult<R> r) Set the result for a global store query.
String	toString()

Methods inherited from class java.lang.Object

equals, getClass, hashCode, notify, notifyAll, wait, wait, wait

Constructor Detail

StateQueryResult

public StateQueryResult()

Method Detail

setGlobalResult

public void setGlobalResult(QueryResult<R> r)

Set the result for a global store query. Used by Kafka Streams and available for tests.

addResult

public void addResult(int partition,
                      QueryResult<R> r)

Set the result for a partitioned store query. Used by Kafka Streams and available for tests.

getPartitionResults

public Map<Integer,QueryResult<R>> getPartitionResults()

The query's result for each partition that executed the query. Empty for global store queries.

getOnlyPartitionResult

public QueryResult<R> getOnlyPartitionResult()

For queries that are expected to match records in only one partition, returns the result.

Throws:

IllegalArgumentException - if the results are not for exactly one partition.

getGlobalResult

public QueryResult<R> getGlobalResult()

The query's result for global store queries. Is null for non-global (partitioned) store queries.

getPosition

public Position getPosition()

The position of the state store at the moment it executed the query. In conjunction with StateQueryRequest.withPositionBound(org.apache.kafka.streams.query.PositionBound), this can be used to achieve a good balance between consistency and availability in which repeated queries are guaranteed to advance in time while allowing reads to be served from any replica that is caught up to that caller's prior observations.

toString

public String toString()

Overrides:

toString in class Object