K - The type of the key in the bundle mapV - The type of the value in the bundle mapIN - Input type for the operator.OUT - Output type for the operator.public abstract class AbstractMapBundleOperator<K,V,IN,OUT> extends AbstractStreamOperator<OUT> implements OneInputStreamOperator<IN,OUT>, BundleTriggerCallback
AbstractMapBundleOperator simply used a java Map to store the input elements
in key-value form. The map key is typically the same with the state key, so we can do some
optimizations before accessing states, like pre aggregate values for each key. And we will
only need to access state every key we have, but not every element we processed.
NOTES: if all elements we processed have different keys, such operator will only increase memory footprint, and will not have any performance improvement.
AbstractStreamOperator.CountingOutput<OUT>chainingStrategy, config, latencyStats, LOG, metrics, output, timeServiceManager| Modifier and Type | Method and Description |
|---|---|
void |
close()
This method is called after all records have been added to the operators via the methods
OneInputStreamOperator.processElement(StreamRecord), or
TwoInputStreamOperator.processElement1(StreamRecord) and
TwoInputStreamOperator.processElement2(StreamRecord). |
void |
finishBundle()
This method is invoked to finish current bundle and start a new one when the trigger was fired.
|
protected abstract K |
getKey(IN input)
Get the key for current processing element, which will be used as the map bundle's key.
|
void |
open()
This method is called immediately before any elements are processed, it should contain the
operator's initialization logic, e.g.
|
void |
prepareSnapshotPreBarrier(long checkpointId)
This method is called when the operator should do a snapshot, before it emits its
own checkpoint barrier.
|
void |
processElement(StreamRecord<IN> element)
Processes one element that arrived at this operator.
|
void |
processWatermark(Watermark mark)
Processes a
Watermark. |
dispose, getChainingStrategy, getContainingTask, getCurrentKey, getExecutionConfig, getInternalTimerService, getKeyedStateBackend, getKeyedStateStore, getMetricGroup, getOperatorConfig, getOperatorID, getOperatorName, getOperatorStateBackend, getOrCreateKeyedState, getPartitionedState, getPartitionedState, getProcessingTimeService, getRuntimeContext, getUserCodeClassloader, initializeState, initializeState, notifyCheckpointComplete, numEventTimeTimers, numProcessingTimeTimers, processLatencyMarker, processLatencyMarker1, processLatencyMarker2, processWatermark1, processWatermark2, reportOrForwardLatencyMarker, setChainingStrategy, setCurrentKey, setKeyContextElement1, setKeyContextElement2, setup, snapshotState, snapshotStateclone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, waitprocessLatencyMarkerdispose, getChainingStrategy, getMetricGroup, getOperatorID, initializeState, setChainingStrategy, setKeyContextElement1, setKeyContextElement2, snapshotStatenotifyCheckpointCompletegetCurrentKey, setCurrentKeypublic void open()
throws Exception
AbstractStreamOperatorThe default implementation does nothing.
open in interface StreamOperator<OUT>open in class AbstractStreamOperator<OUT>Exception - An exception in this method causes the operator to fail.public void processElement(StreamRecord<IN> element) throws Exception
OneInputStreamOperatorprocessElement in interface OneInputStreamOperator<IN,OUT>Exceptionprotected abstract K getKey(IN input) throws Exception
Exceptionpublic void finishBundle()
throws Exception
BundleTriggerCallbackfinishBundle in interface BundleTriggerCallbackException - This method may throw exceptions. Throwing an exception will cause the operation
to fail and may trigger recovery.public void processWatermark(Watermark mark) throws Exception
OneInputStreamOperatorWatermark.
This method is guaranteed to not be called concurrently with other methods of the operator.processWatermark in interface OneInputStreamOperator<IN,OUT>processWatermark in class AbstractStreamOperator<OUT>ExceptionWatermarkpublic void prepareSnapshotPreBarrier(long checkpointId)
throws Exception
StreamOperatorThis 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.
prepareSnapshotPreBarrier in interface StreamOperator<OUT>prepareSnapshotPreBarrier in class AbstractStreamOperator<OUT>checkpointId - The ID of the checkpoint.Exception - Throwing an exception here causes the operator to fail and go into recovery.public void close()
throws Exception
AbstractStreamOperatorOneInputStreamOperator.processElement(StreamRecord), or
TwoInputStreamOperator.processElement1(StreamRecord) and
TwoInputStreamOperator.processElement2(StreamRecord).
The method is expected to flush all remaining buffered data. Exceptions during this flushing of buffered should be propagated, in order to cause the operation to be recognized asa failed, because the last data items are not processed properly.
close in interface StreamOperator<OUT>close in class AbstractStreamOperator<OUT>Exception - An exception in this method causes the operator to fail.Copyright © 2014–2020 The Apache Software Foundation. All rights reserved.