Package org.apache.flink.runtime.state.v2

Class DefaultKeyedStateStoreV2

java.lang.Object

org.apache.flink.runtime.state.v2.DefaultKeyedStateStoreV2

All Implemented Interfaces:

KeyedStateStoreV2

public class DefaultKeyedStateStoreV2
extends Object
implements KeyedStateStoreV2

Default implementation of KeyedStateStoreV2.

Constructor Summary

Constructors

Constructor	Description
DefaultKeyedStateStoreV2(AsyncKeyedStateBackend asyncKeyedStateBackend)

Method Summary

Modifier and Type	Method	Description
<IN,ACC,OUT> AggregatingState<IN,OUT>	getAggregatingState(AggregatingStateDescriptor<IN,ACC,OUT> stateProperties)	Gets a handle to the system's key/value aggregating state.
<T> ListState<T>	getListState(ListStateDescriptor<T> stateProperties)	Gets a handle to the system's key / value list state.
<UK,UV> MapState<UK,UV>	getMapState(MapStateDescriptor<UK,UV> stateProperties)	Gets a handle to the system's key/value map state.
<T> ReducingState<T>	getReducingState(ReducingStateDescriptor<T> stateProperties)	Gets a handle to the system's key/value reducing state.
<T> ValueState<T>	getValueState(ValueStateDescriptor<T> stateProperties)	Gets a handle to the system's ValueState.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

DefaultKeyedStateStoreV2

public DefaultKeyedStateStoreV2(@Nonnull
                                AsyncKeyedStateBackend asyncKeyedStateBackend)

Method Detail

getValueState

public <T> ValueState<T> getValueState(@Nonnull
                                       ValueStateDescriptor<T> stateProperties)

Description copied from interface: KeyedStateStoreV2

Gets a handle to the system's ValueState. The key/value state is only accessible if the function is executed on a KeyedStream. On each access, the state exposes the value for the key of the element currently processed by the function. Each function may have multiple partitioned states, addressed with different names.

Because the scope of each value is the key of the currently processed element, and the elements are distributed by the Flink runtime, the system can transparently scale out and redistribute the state and KeyedStream.

Specified by:

getValueState in interface KeyedStateStoreV2

Type Parameters:

T - The type of value stored in the state.

Parameters:

stateProperties - The descriptor defining the properties of the state.

Returns:

The partitioned state object.

getListState

public <T> ListState<T> getListState(@Nonnull
                                     ListStateDescriptor<T> stateProperties)

Description copied from interface: KeyedStateStoreV2

Gets a handle to the system's key / value list state. This state is optimized for state that holds lists. One can adds elements to the list, or retrieve the list as a whole. This state is only accessible if the function is executed on a KeyedStream.

Specified by:

getListState in interface KeyedStateStoreV2

Type Parameters:

T - The type of value stored in the state.

Parameters:

stateProperties - The descriptor defining the properties of the state.

Returns:

The partitioned state object.

getMapState

public <UK,UV> MapState<UK,UV> getMapState(@Nonnull
                                                       MapStateDescriptor<UK,UV> stateProperties)

Description copied from interface: KeyedStateStoreV2

Gets a handle to the system's key/value map state. This state is only accessible if the function is executed on a KeyedStream.

Specified by:

getMapState in interface KeyedStateStoreV2

Type Parameters:

UK - The type of the user keys stored in the state.

UV - The type of the user values stored in the state.

Parameters:

stateProperties - The descriptor defining the properties of the state.

Returns:

The partitioned state object.

getReducingState

public <T> ReducingState<T> getReducingState(@Nonnull
                                             ReducingStateDescriptor<T> stateProperties)

Description copied from interface: KeyedStateStoreV2

Gets a handle to the system's key/value reducing state. This state is optimized for state that aggregates values.

This state is only accessible if the function is executed on a KeyedStream.

Specified by:

getReducingState in interface KeyedStateStoreV2

Type Parameters:

T - The type of value stored in the state.

Parameters:

stateProperties - The descriptor defining the properties of the stats.

Returns:

The partitioned state object.

getAggregatingState

public <IN,ACC,OUT> AggregatingState<IN,OUT> getAggregatingState(@Nonnull
                                                                                   AggregatingStateDescriptor<IN,ACC,OUT> stateProperties)

Description copied from interface: KeyedStateStoreV2

Gets a handle to the system's key/value aggregating state. This state is only accessible if the function is executed on a KeyedStream.

Specified by:

getAggregatingState in interface KeyedStateStoreV2

Type Parameters:

IN - The type of the values that are added to the state.

ACC - The type of the accumulator (intermediate aggregation state).

OUT - The type of the values that are returned from the state.

Parameters:

stateProperties - The descriptor defining the properties of the stats.

Returns:

The partitioned state object.