Package org.apache.flink.runtime.asyncprocessing.operators

Class AbstractAsyncStateStreamOperator<OUT>

java.lang.Object

org.apache.flink.streaming.api.operators.AbstractStreamOperator<OUT>

org.apache.flink.runtime.asyncprocessing.operators.AbstractAsyncStateStreamOperator<OUT>

All Implemented Interfaces:

Serializable, CheckpointListener, KeyContext, KeyContextHandler, StreamOperator<OUT>, StreamOperatorStateHandler.CheckpointedStreamOperator, YieldingOperator<OUT>, AsyncStateProcessing, AsyncStateProcessingOperator

Direct Known Subclasses:

AbstractAsyncStateStreamingJoinOperator, AbstractAsyncStateUdfStreamOperator

@Internal
public abstract class AbstractAsyncStateStreamOperator<OUT>
extends AbstractStreamOperator<OUT>
implements AsyncStateProcessingOperator

This operator is an abstract class that give the AbstractStreamOperator the ability to perform AsyncStateProcessing. The aim is to make any subclass of AbstractStreamOperator could manipulate async state with only a change of base class.

See Also:

Serialized Form

Field Summary

Fields inherited from class org.apache.flink.streaming.api.operators.AbstractStreamOperator

config, lastRecordAttributes1, lastRecordAttributes2, latencyStats, metrics, output, processingTimeService, stateHandler, stateKeySelector1, stateKeySelector2, timeServiceManager

Constructor Summary

Constructors

Constructor	Description
AbstractAsyncStateStreamOperator()

Method Summary

Modifier and Type	Method	Description
<K> void	asyncProcessWithKey(K key, ThrowingRunnable<Exception> processing)	Asynchronously process a code with a key provided.
void	close()	This method is called at the very end of the operator's life, both in the case of a successful completion of the operation, and in the case of a failure and canceling.
void	finish()	This method is called at the end of data processing.
Object	getCurrentKey()
ElementOrder	getElementOrder()	Get the ElementOrder of this operator.
<K,N> InternalTimerService<N>	getInternalTimerService(String name, TypeSerializer<N> namespaceSerializer, Triggerable<K,N> triggerable)	Returns a InternalTimerService that can be used to query current processing time and event time and to set timers.
protected <N,S extends State,T> S	getOrCreateKeyedState(N defaultNamespace, TypeSerializer<N> namespaceSerializer, StateDescriptor<T> stateDescriptor)	Create new state (v2) based on new state descriptor.
<T> ThrowingConsumer<StreamRecord<T>,Exception>	getRecordProcessor(int inputId)	Get the record processor that could process record from input, which is the only entry for async processing.
void	initializeState(StreamTaskStateInitializer streamTaskStateManager)	Initialize necessary state components for AbstractStreamOperator.
boolean	isAsyncStateProcessingEnabled()	Get if the async state processing is enabled for this input/operator.
void	postProcessElement()	A callback that will be triggered after an element finishes processElement.
void	prepareSnapshotPreBarrier(long checkpointId)	This method is called when the operator should do a snapshot, before it emits its own checkpoint barrier.
void	preserveRecordOrderAndProcess(ThrowingRunnable<Exception> processing)	Check the order of same-key record, and then process the record.
void	processWatermark(Watermark mark)
void	processWatermarkStatus(WatermarkStatus watermarkStatus)
<T> void	setAsyncKeyedContextElement(StreamRecord<T> record, KeySelector<T,?> keySelector)	Set key context for async state processing.
void	setKeyContextElement1(StreamRecord record)
void	setKeyContextElement2(StreamRecord record)
OperatorSnapshotFutures	snapshotState(long checkpointId, long timestamp, CheckpointOptions checkpointOptions, CheckpointStreamFactory factory)	Called to draw a state snapshot from the operator.

Methods inherited from class org.apache.flink.streaming.api.operators.AbstractStreamOperator

getContainingTask, getExecutionConfig, getKeyedStateBackend, getKeyedStateStore, getMetricGroup, getOperatorConfig, getOperatorID, getOperatorName, getOperatorStateBackend, getOrCreateKeyedState, getPartitionedState, getPartitionedState, getProcessingTimeService, getRuntimeContext, getStateKeySelector1, getStateKeySelector2, getTimeServiceManager, getUserCodeClassloader, hasKeyContext1, hasKeyContext2, initializeState, isUsingCustomRawKeyedState, notifyCheckpointAborted, notifyCheckpointComplete, open, processLatencyMarker, processLatencyMarker1, processLatencyMarker2, processRecordAttributes, processRecordAttributes1, processRecordAttributes2, processWatermark1, processWatermark2, processWatermarkStatus1, processWatermarkStatus2, reportOrForwardLatencyMarker, setCurrentKey, setMailboxExecutor, setProcessingTimeService, setup, snapshotState, useSplittableTimers

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.streaming.api.operators.KeyContextHandler

hasKeyContext

Methods inherited from interface org.apache.flink.streaming.api.operators.StreamOperator

getOperatorAttributes

Constructor Detail

AbstractAsyncStateStreamOperator

public AbstractAsyncStateStreamOperator()

Method Detail

initializeState

public void initializeState(StreamTaskStateInitializer streamTaskStateManager)
                     throws Exception

Initialize necessary state components for AbstractStreamOperator.

Specified by:

initializeState in interface StreamOperator<OUT>

Overrides:

initializeState in class AbstractStreamOperator<OUT>

Throws:

Exception

isAsyncStateProcessingEnabled

public boolean isAsyncStateProcessingEnabled()

Description copied from interface: AsyncStateProcessing

Get if the async state processing is enabled for this input/operator.

Specified by:

isAsyncStateProcessingEnabled in interface AsyncStateProcessing

Returns:

ture if async state processing is enabled.

getElementOrder

public ElementOrder getElementOrder()

Description copied from interface: AsyncStateProcessingOperator

Get the ElementOrder of this operator.

Specified by:

getElementOrder in interface AsyncStateProcessingOperator

setAsyncKeyedContextElement

public final <T> void setAsyncKeyedContextElement(StreamRecord<T> record,
                                                  KeySelector<T,?> keySelector)
                                           throws Exception

Description copied from interface: AsyncStateProcessingOperator

Set key context for async state processing.

Specified by:

setAsyncKeyedContextElement in interface AsyncStateProcessingOperator

Type Parameters:

T - the type of the record.

Parameters:

record - the record.

keySelector - the key selector to select a key from record.

Throws:

Exception

postProcessElement

public final void postProcessElement()

Description copied from interface: AsyncStateProcessingOperator

A callback that will be triggered after an element finishes processElement.

Specified by:

postProcessElement in interface AsyncStateProcessingOperator

preserveRecordOrderAndProcess

public final void preserveRecordOrderAndProcess(ThrowingRunnable<Exception> processing)

Description copied from interface: AsyncStateProcessingOperator

Check the order of same-key record, and then process the record. Mainly used when the AsyncStateProcessingOperator.getElementOrder() returns ElementOrder.RECORD_ORDER.

Specified by:

preserveRecordOrderAndProcess in interface AsyncStateProcessingOperator

Parameters:

processing - the record processing logic.

asyncProcessWithKey

public <K> void asyncProcessWithKey(K key,
                                    ThrowingRunnable<Exception> processing)

Description copied from interface: AsyncStateProcessingOperator

Asynchronously process a code with a key provided.

Specified by:

asyncProcessWithKey in interface AsyncStateProcessingOperator

Type Parameters:

K - the type of key.

Parameters:

key - the specified key.

processing - the process logic.

getRecordProcessor

public final <T> ThrowingConsumer<StreamRecord<T>,Exception> getRecordProcessor(int inputId)

Description copied from interface: AsyncStateProcessing

Get the record processor that could process record from input, which is the only entry for async processing.

Specified by:

getRecordProcessor in interface AsyncStateProcessing

Parameters:

inputId - the input identifier, start from 1. Borrow the design from org.apache.flink.streaming.api.operators.AbstractInput#inputId. This is only relevant if there is multiple inputs for the instance.

getOrCreateKeyedState

protected <N,S extends State,T> S getOrCreateKeyedState(@Nonnull
                                                                    N defaultNamespace,
                                                                    @Nonnull
                                                                    TypeSerializer<N> namespaceSerializer,
                                                                    @Nonnull
                                                                    StateDescriptor<T> stateDescriptor)
                                                             throws Exception

Create new state (v2) based on new state descriptor.

Throws:

Exception

prepareSnapshotPreBarrier

public void prepareSnapshotPreBarrier(long checkpointId)
                               throws Exception

Description copied from interface: StreamOperator

This method is called when the operator should do a snapshot, before it emits its own checkpoint barrier.

This method is intended not for any actual state persistence, but only for emitting some data before emitting the checkpoint barrier. Operators that maintain some small transient state that is inefficient to checkpoint (especially when it would need to be checkpointed in a re-scalable way) but can simply be sent downstream before the checkpoint. An example are opportunistic pre-aggregation operators, which have small the pre-aggregation state that is frequently flushed downstream.

Important: This method should not be used for any actual state snapshot logic, because it will inherently be within the synchronous part of the operator's checkpoint. If heavy work is done within this method, it will affect latency and downstream checkpoint alignments.

Specified by:

prepareSnapshotPreBarrier in interface StreamOperator<OUT>

Overrides:

prepareSnapshotPreBarrier in class AbstractStreamOperator<OUT>

Parameters:

checkpointId - The ID of the checkpoint.

Throws:

Exception - Throwing an exception here causes the operator to fail and go into recovery.

snapshotState

public OperatorSnapshotFutures snapshotState(long checkpointId,
                                             long timestamp,
                                             CheckpointOptions checkpointOptions,
                                             CheckpointStreamFactory factory)
                                      throws Exception

Description copied from interface: StreamOperator

Called to draw a state snapshot from the operator.

Specified by:

snapshotState in interface StreamOperator<OUT>

Overrides:

snapshotState in class AbstractStreamOperator<OUT>

Returns:

a runnable future to the state handle that points to the snapshotted state. For synchronous implementations, the runnable might already be finished.

Throws:

Exception - exception that happened during snapshotting.

getInternalTimerService

public <K,N> InternalTimerService<N> getInternalTimerService(String name,
                                                                   TypeSerializer<N> namespaceSerializer,
                                                                   Triggerable<K,N> triggerable)

Returns a InternalTimerService that can be used to query current processing time and event time and to set timers. An operator can have several timer services, where each has its own namespace serializer. Timer services are differentiated by the string key that is given when requesting them, if you call this method with the same key multiple times you will get the same timer service instance in subsequent requests.

Timers are always scoped to a key, the currently active key of a keyed stream operation. When a timer fires, this key will also be set as the currently active key.

Each timer has attached metadata, the namespace. Different timer services can have a different namespace type. If you don't need namespace differentiation you can use VoidNamespaceSerializer as the namespace serializer.

Overrides:

getInternalTimerService in class AbstractStreamOperator<OUT>

Type Parameters:

N - The type of the timer namespace.

Parameters:

name - The name of the requested timer service. If no service exists under the given name a new one will be created and returned.

namespaceSerializer - TypeSerializer for the timer namespace.

triggerable - The Triggerable that should be invoked when timers fire

setKeyContextElement1

public void setKeyContextElement1(StreamRecord record)
                           throws Exception

Specified by:

setKeyContextElement1 in interface StreamOperator<OUT>

Overrides:

setKeyContextElement1 in class AbstractStreamOperator<OUT>

Throws:

Exception

setKeyContextElement2

public void setKeyContextElement2(StreamRecord record)
                           throws Exception

Specified by:

setKeyContextElement2 in interface StreamOperator<OUT>

Overrides:

setKeyContextElement2 in class AbstractStreamOperator<OUT>

Throws:

Exception

getCurrentKey

public Object getCurrentKey()

Specified by:

getCurrentKey in interface KeyContext

Overrides:

getCurrentKey in class AbstractStreamOperator<OUT>

processWatermark

public void processWatermark(Watermark mark)
                      throws Exception

Overrides:

processWatermark in class AbstractStreamOperator<OUT>

Throws:

Exception

processWatermarkStatus

public void processWatermarkStatus(WatermarkStatus watermarkStatus)
                            throws Exception

Overrides:

processWatermarkStatus in class AbstractStreamOperator<OUT>

Throws:

Exception

finish

public void finish()
            throws Exception

Description copied from interface: StreamOperator

This method is called at the end of data processing.

The method is expected to flush all remaining buffered data. Exceptions during this flushing of buffered data should be propagated, in order to cause the operation to be recognized as failed, because the last data items are not processed properly.

After this method is called, no more records can be produced for the downstream operators.

WARNING: It is not safe to use this method to commit any transactions or other side effects! You can use this method to flush any buffered data that can later on be committed e.g. in a CheckpointListener.notifyCheckpointComplete(long).

NOTE:This method does not need to close any resources. You should release external resources in the StreamOperator.close() method.

Specified by:

finish in interface StreamOperator<OUT>

Overrides:

finish in class AbstractStreamOperator<OUT>

Throws:

Exception - An exception in this method causes the operator to fail.

close

public void close()
           throws Exception

Description copied from interface: StreamOperator

This method is called at the very end of the operator's life, both in the case of a successful completion of the operation, and in the case of a failure and canceling.

This method is expected to make a thorough effort to release all resources that the operator has acquired.

NOTE:It can not emit any records! If you need to emit records at the end of processing, do so in the StreamOperator.finish() method.

Specified by:

close in interface StreamOperator<OUT>

Overrides:

close in class AbstractStreamOperator<OUT>

Throws:

Exception