Package 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

Nested Class Summary

Nested classes/interfaces inherited from interface org.apache.flink.runtime.state.StateBackend

StateBackend.CustomInitializationMetrics, StateBackend.KeyedStateBackendParameters<K>, StateBackend.OperatorStateBackendParameters

Field Summary

Fields

Modifier and Type	Field	Description
protected LatencyTrackingStateConfig.Builder	latencyTrackingConfigBuilder

Constructor Summary

Constructors

Constructor	Description
AbstractStateBackend()

Method Summary

Modifier and Type	Method	Description
abstract <K> AbstractKeyedStateBackend<K>	createKeyedStateBackend(StateBackend.KeyedStateBackendParameters<K> parameters)	Creates a new CheckpointableKeyedStateBackend that is responsible for holding keyed state and checkpointing it.
abstract OperatorStateBackend	createOperatorStateBackend(StateBackend.OperatorStateBackendParameters parameters)	Creates a new OperatorStateBackend that can be used for storing operator state.
static StreamCompressionDecorator	getCompressionDecorator(org.apache.flink.api.common.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

createAsyncKeyedStateBackend, getName, supportsAsyncKeyedStateBackend, supportsNoClaimRestoreMode, supportsSavepointFormat, useManagedMemory

Field Details

latencyTrackingConfigBuilder

protected LatencyTrackingStateConfig.Builder latencyTrackingConfigBuilder

Constructor Details

AbstractStateBackend

public AbstractStateBackend()

Method Details

getCompressionDecorator

public static StreamCompressionDecorator getCompressionDecorator(org.apache.flink.api.common.ExecutionConfig executionConfig)

createKeyedStateBackend

public abstract <K> AbstractKeyedStateBackend<K> createKeyedStateBackend(StateBackend.KeyedStateBackendParameters<K> parameters)
                                                                  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:

parameters - The arguments bundle for creating CheckpointableKeyedStateBackend.

Returns:

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

Throws:

IOException

createOperatorStateBackend

public abstract OperatorStateBackend createOperatorStateBackend(StateBackend.OperatorStateBackendParameters parameters)
                                                         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:

parameters - The arguments bundle for creating OperatorStateBackend.

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.