@Internal public class ContinuousFileReaderOperator<OUT,T extends TimestampedInputSplit> extends AbstractStreamOperator<OUT> implements OneInputStreamOperator<T,OUT>, OutputTypeConfigurable<OUT>
splits received from the preceding
ContinuousFileMonitoringFunction. Contrary to the ContinuousFileMonitoringFunction which has a parallelism of 1, this operator can have DOP > 1.
This implementation uses MailboxExecutor to execute each action and state machine
approach. The workflow is the following:
IDLE
OPENING
and enqueue a mail to process
it
READING, read one record, re-enqueue self
IDLE
On close:
IDLE then close immediately
CLOSING, call yield in a loop until state is CLOSED
yield() causes remaining records (and splits) to be
processed in the same way as above
Using MailboxExecutor allows to avoid explicit synchronization. At most one mail
should be enqueued at any given time.
Using FSM approach allows to explicitly define states and enforce transitions between them.
chainingStrategy, config, lastRecordAttributes1, lastRecordAttributes2, latencyStats, metrics, output, processingTimeService, stateHandler, stateKeySelector1, stateKeySelector2, timeServiceManager| Modifier and Type | Method and Description |
|---|---|
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.
|
void |
initializeState(StateInitializationContext context)
Stream operators with state which can be restored need to override this hook method.
|
void |
open()
This method is called immediately before any elements are processed, it should contain the
operator's initialization logic, e.g. state initialization.
|
void |
processElement(StreamRecord<T> element)
Processes one element that arrived on this input of the
MultipleInputStreamOperator. |
void |
processWatermark(Watermark mark)
Processes a
Watermark that arrived on the first input of this two-input operator. |
void |
setOutputType(TypeInformation<OUT> outTypeInfo,
ExecutionConfig executionConfig)
Is called by the
org.apache.flink.streaming.api.graph.StreamGraph#addOperator(Integer,
String, StreamOperator, TypeInformation, TypeInformation, String) method when the org.apache.flink.streaming.api.graph.StreamGraph is generated. |
void |
snapshotState(StateSnapshotContext context)
Stream operators with state, which want to participate in a snapshot need to override this
hook method.
|
getChainingStrategy, getContainingTask, getCurrentKey, getExecutionConfig, getInternalTimerService, getKeyedStateBackend, getKeyedStateStore, getMetricGroup, getOperatorConfig, getOperatorID, getOperatorName, getOperatorStateBackend, getOrCreateKeyedState, getPartitionedState, getPartitionedState, getProcessingTimeService, getRuntimeContext, getStateKeySelector1, getStateKeySelector2, getTimeServiceManager, getUserCodeClassloader, hasKeyContext1, hasKeyContext2, initializeState, isUsingCustomRawKeyedState, notifyCheckpointAborted, notifyCheckpointComplete, prepareSnapshotPreBarrier, processLatencyMarker, processLatencyMarker1, processLatencyMarker2, processRecordAttributes, processRecordAttributes1, processRecordAttributes2, processWatermark1, processWatermark2, processWatermarkStatus, processWatermarkStatus1, processWatermarkStatus2, reportOrForwardLatencyMarker, setChainingStrategy, setCurrentKey, setKeyContextElement1, setKeyContextElement2, setMailboxExecutor, setProcessingTimeService, setup, snapshotState, useSplittableTimersclone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, waitsetKeyContextElementgetMetricGroup, getOperatorAttributes, getOperatorID, initializeState, prepareSnapshotPreBarrier, setKeyContextElement1, setKeyContextElement2, snapshotStatenotifyCheckpointAborted, notifyCheckpointCompletegetCurrentKey, setCurrentKeyprocessLatencyMarker, processRecordAttributes, processWatermarkStatushasKeyContextpublic void initializeState(StateInitializationContext context) throws Exception
AbstractStreamOperatorinitializeState in interface StreamOperatorStateHandler.CheckpointedStreamOperatorinitializeState in class AbstractStreamOperator<OUT>context - context that allows to register different states.Exceptionpublic 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<T> element) throws Exception
InputMultipleInputStreamOperator.
This method is guaranteed to not be called concurrently with other methods of the operator.processElement in interface Input<T extends TimestampedInputSplit>Exceptionpublic void processWatermark(Watermark mark) throws Exception
InputWatermark that arrived on the first input of this two-input operator.
This method is guaranteed to not be called concurrently with other methods of the operator.processWatermark in interface Input<T extends TimestampedInputSplit>processWatermark in class AbstractStreamOperator<OUT>ExceptionWatermarkpublic void finish()
throws Exception
StreamOperatorThe 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.
finish in interface StreamOperator<OUT>finish in class AbstractStreamOperator<OUT>Exception - An exception in this method causes the operator to fail.public void close()
throws Exception
StreamOperatorThis 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.
close in interface StreamOperator<OUT>close in class AbstractStreamOperator<OUT>Exceptionpublic void snapshotState(StateSnapshotContext context) throws Exception
AbstractStreamOperatorsnapshotState in interface StreamOperatorStateHandler.CheckpointedStreamOperatorsnapshotState in class AbstractStreamOperator<OUT>context - context that provides information and means required for taking a snapshotExceptionpublic void setOutputType(TypeInformation<OUT> outTypeInfo, ExecutionConfig executionConfig)
OutputTypeConfigurableorg.apache.flink.streaming.api.graph.StreamGraph#addOperator(Integer,
String, StreamOperator, TypeInformation, TypeInformation, String) method when the org.apache.flink.streaming.api.graph.StreamGraph is generated. The method is called with the
output TypeInformation which is also used for the org.apache.flink.streaming.runtime.tasks.StreamTask output serializer.setOutputType in interface OutputTypeConfigurable<OUT>outTypeInfo - Output type information of the org.apache.flink.streaming.runtime.tasks.StreamTaskexecutionConfig - Execution configurationCopyright © 2014–2024 The Apache Software Foundation. All rights reserved.