org.apache.flink.runtime.state

Class AbstractStateBackend

java.lang.Object

org.apache.flink.runtime.state.AbstractStateBackend

All Implemented Interfaces:

Serializable, StateBackend

Direct Known Subclasses:

AbstractFileStateBackend, AbstractManagedMemoryStateBackend, HashMapStateBackend

@PublicEvolving
public abstract class AbstractStateBackend
extends Object
implements StateBackend, Serializable

An abstract base implementation of the StateBackend interface.

This class has currently no contents and only kept to not break the prior class hierarchy for users.

See Also:

Serialized Form

Field Summary

Fields

Modifier and Type	Field and Description
protected LatencyTrackingStateConfig.Builder	latencyTrackingConfigBuilder

Constructor Summary

Constructors

Constructor and Description
AbstractStateBackend()

Method Summary

Modifier and Type	Method and Description
abstract <K> AbstractKeyedStateBackend<K>	createKeyedStateBackend(Environment env, JobID jobID, String operatorIdentifier, TypeSerializer<K> keySerializer, int numberOfKeyGroups, KeyGroupRange keyGroupRange, TaskKvStateRegistry kvStateRegistry, TtlTimeProvider ttlTimeProvider, MetricGroup metricGroup, Collection<KeyedStateHandle> stateHandles, CloseableRegistry cancelStreamRegistry) Creates a new CheckpointableKeyedStateBackend that is responsible for holding keyed state and checkpointing it.
abstract OperatorStateBackend	createOperatorStateBackend(Environment env, String operatorIdentifier, Collection<OperatorStateHandle> stateHandles, CloseableRegistry cancelStreamRegistry) Creates a new OperatorStateBackend that can be used for storing operator state.
static StreamCompressionDecorator	getCompressionDecorator(ExecutionConfig executionConfig)

Methods inherited from class java.lang.Object

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

Methods inherited from interface org.apache.flink.runtime.state.StateBackend

createKeyedStateBackend, getName, supportsNoClaimRestoreMode, supportsSavepointFormat, useManagedMemory

Field Detail

latencyTrackingConfigBuilder

protected LatencyTrackingStateConfig.Builder latencyTrackingConfigBuilder

Constructor Detail

AbstractStateBackend

public AbstractStateBackend()

Method Detail

getCompressionDecorator

public static StreamCompressionDecorator getCompressionDecorator(ExecutionConfig executionConfig)

createKeyedStateBackend

public abstract <K> AbstractKeyedStateBackend<K> createKeyedStateBackend(Environment env,
                                                                         JobID jobID,
                                                                         String operatorIdentifier,
                                                                         TypeSerializer<K> keySerializer,
                                                                         int numberOfKeyGroups,
                                                                         KeyGroupRange keyGroupRange,
                                                                         TaskKvStateRegistry kvStateRegistry,
                                                                         TtlTimeProvider ttlTimeProvider,
                                                                         MetricGroup metricGroup,
                                                                         @Nonnull
                                                                         Collection<KeyedStateHandle> stateHandles,
                                                                         CloseableRegistry cancelStreamRegistry)
                                                                  throws IOException

Description copied from interface: StateBackend

Creates a new CheckpointableKeyedStateBackend that is responsible for holding keyed state and checkpointing it.

Keyed State is state where each value is bound to a key.

Specified by:

createKeyedStateBackend in interface StateBackend

Type Parameters:

K - The type of the keys by which the state is organized.

Parameters:

env - The environment of the task.

jobID - The ID of the job that the task belongs to.

operatorIdentifier - The identifier text of the operator.

keySerializer - The key-serializer for the operator.

numberOfKeyGroups - The number of key-groups aka max parallelism.

keyGroupRange - Range of key-groups for which the to-be-created backend is responsible.

kvStateRegistry - KvStateRegistry helper for this task.

ttlTimeProvider - Provider for TTL logic to judge about state expiration.

metricGroup - The parent metric group for all state backend metrics.

stateHandles - The state handles for restore.

cancelStreamRegistry - The registry to which created closeable objects will be registered during restore.

Returns:

The Keyed State Backend for the given job, operator, and key group range.

Throws:

IOException

createOperatorStateBackend

public abstract OperatorStateBackend createOperatorStateBackend(Environment env,
                                                                String operatorIdentifier,
                                                                @Nonnull
                                                                Collection<OperatorStateHandle> stateHandles,
                                                                CloseableRegistry cancelStreamRegistry)
                                                         throws Exception

Description copied from interface: StateBackend

Creates a new OperatorStateBackend that can be used for storing operator state.

Operator state is state that is associated with parallel operator (or function) instances, rather than with keys.

Specified by:

createOperatorStateBackend in interface StateBackend

Parameters:

env - The runtime environment of the executing task.

operatorIdentifier - The identifier of the operator whose state should be stored.

stateHandles - The state handles for restore.

cancelStreamRegistry - The registry to register streams to close if task canceled.

Returns:

The OperatorStateBackend for operator identified by the job and operator identifier.

Throws:

Exception - This method may forward all exceptions that occur while instantiating the backend.