org.apache.flink.runtime.state

Interface AsyncKeyedStateBackend

All Superinterfaces:

AutoCloseable, Closeable, org.apache.flink.util.Disposable

@Internal
public interface AsyncKeyedStateBackend
extends org.apache.flink.util.Disposable, Closeable

An async keyed state backend provides methods supporting to access keyed state asynchronously and in batch.

Method Summary

Modifier and Type	Method and Description
<SV,S extends org.apache.flink.api.common.state.v2.State> S	createState(StateDescriptor<SV> stateDesc) Creates and returns a new state.
StateExecutor	createStateExecutor() Creates a StateExecutor which supports to execute a batch of state requests asynchronously.
void	dispose()
void	setup(StateRequestHandler stateRequestHandler) Initializes with some contexts.

Methods inherited from interface java.io.Closeable

close

Method Detail

setup

void setup(@Nonnull
           StateRequestHandler stateRequestHandler)

Initializes with some contexts.

Parameters:

stateRequestHandler - which handles state request.

createState

@Nonnull
<SV,S extends org.apache.flink.api.common.state.v2.State> S createState(@Nonnull
                                                                                 StateDescriptor<SV> stateDesc)
                                                                          throws Exception

Creates and returns a new state.

Type Parameters:

SV - The type of the stored state value.

S - The type of the public API state.

Parameters:

stateDesc - The StateDescriptor that contains the name of the state.

Throws:

Exception - Exceptions may occur during initialization of the state.

createStateExecutor

@Nonnull
StateExecutor createStateExecutor()

Creates a StateExecutor which supports to execute a batch of state requests asynchronously.

Notice that the AsyncKeyedStateBackend is responsible for shutting down the StateExecutors created by itself when they are no longer in use.

Returns:

a StateExecutor which supports to execute a batch of state requests asynchronously.

dispose

void dispose()

Specified by:

dispose in interface org.apache.flink.util.Disposable