org.apache.flink.streaming.api.functions.source

Class ContinuousFileReaderOperator<OUT>

java.lang.Object

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

org.apache.flink.streaming.api.functions.source.ContinuousFileReaderOperator<OUT>

All Implemented Interfaces:

Serializable, org.apache.flink.runtime.state.CheckpointListener, KeyContext, OneInputStreamOperator<TimestampedFileInputSplit,OUT>, OutputTypeConfigurable<OUT>, SetupableStreamOperator<OUT>, StreamOperator<OUT>, org.apache.flink.util.Disposable

@Internal
public class ContinuousFileReaderOperator<OUT>
extends AbstractStreamOperator<OUT>
implements OneInputStreamOperator<TimestampedFileInputSplit,OUT>, OutputTypeConfigurable<OUT>

The operator that reads the splits received from the preceding ContinuousFileMonitoringFunction. Contrary to the ContinuousFileMonitoringFunction which has a parallelism of 1, this operator can have DOP > 1.

As soon as a split descriptor is received, it is put in a queue, and have another thread read the actual data of the split. This architecture allows the separation of the reading thread from the one emitting the checkpoint barriers, thus removing any potential back-pressure.

See Also:

Serialized Form

Nested Class Summary

Nested classes/interfaces inherited from class org.apache.flink.streaming.api.operators.AbstractStreamOperator

AbstractStreamOperator.CountingOutput<OUT>

Field Summary

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

chainingStrategy, config, latencyStats, metrics, output, timeServiceManager

Constructor Summary

Constructors

Constructor and Description
ContinuousFileReaderOperator(org.apache.flink.api.common.io.FileInputFormat<OUT> format)

Method Summary

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	dispose() 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	initializeState(org.apache.flink.runtime.state.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.
void	processElement(StreamRecord<TimestampedFileInputSplit> element) Processes one element that arrived at this operator.
void	processWatermark(Watermark mark) Processes a Watermark.
void	setOutputType(org.apache.flink.api.common.typeinfo.TypeInformation<OUT> outTypeInfo, org.apache.flink.api.common.ExecutionConfig executionConfig) Is called by the org.apache.flink.streaming.api.graph.StreamGraph#addOperator(Integer, String, StreamOperator, TypeInformation, TypeInformation, String) method when the StreamGraph is generated.
void	snapshotState(org.apache.flink.runtime.state.StateSnapshotContext context) Stream operators with state, which want to participate in a snapshot need to override this hook method.

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

getChainingStrategy, getContainingTask, getCurrentKey, getExecutionConfig, getInternalTimerService, getKeyedStateBackend, getKeyedStateStore, getMetricGroup, getOperatorConfig, getOperatorID, getOperatorName, getOperatorStateBackend, getOrCreateKeyedState, getPartitionedState, getPartitionedState, getProcessingTimeService, getRuntimeContext, getUserCodeClassloader, initializeState, notifyCheckpointComplete, numEventTimeTimers, numProcessingTimeTimers, prepareSnapshotPreBarrier, processLatencyMarker, processLatencyMarker1, processLatencyMarker2, processWatermark1, processWatermark2, reportOrForwardLatencyMarker, setChainingStrategy, setCurrentKey, setKeyContextElement1, setKeyContextElement2, setup, snapshotState

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.OneInputStreamOperator

processLatencyMarker

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

getChainingStrategy, getMetricGroup, getOperatorID, initializeState, prepareSnapshotPreBarrier, setChainingStrategy, setKeyContextElement1, setKeyContextElement2, snapshotState

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

notifyCheckpointComplete

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

getCurrentKey, setCurrentKey

Constructor Detail

ContinuousFileReaderOperator

public ContinuousFileReaderOperator(org.apache.flink.api.common.io.FileInputFormat<OUT> format)

Method Detail

setOutputType

public void setOutputType(org.apache.flink.api.common.typeinfo.TypeInformation<OUT> outTypeInfo,
                          org.apache.flink.api.common.ExecutionConfig executionConfig)

Description copied from interface: OutputTypeConfigurable

Is called by the org.apache.flink.streaming.api.graph.StreamGraph#addOperator(Integer, String, StreamOperator, TypeInformation, TypeInformation, String) method when the StreamGraph is generated. The method is called with the output TypeInformation which is also used for the StreamTask output serializer.

Specified by:

setOutputType in interface OutputTypeConfigurable<OUT>

Parameters:

outTypeInfo - Output type information of the StreamTask

executionConfig - Execution configuration

initializeState

public void initializeState(org.apache.flink.runtime.state.StateInitializationContext context)
                     throws Exception

Description copied from class: AbstractStreamOperator

Stream operators with state which can be restored need to override this hook method.

Overrides:

initializeState in class AbstractStreamOperator<OUT>

Parameters:

context - context that allows to register different states.

Throws:

Exception

open

public void open()
          throws Exception

Description copied from class: AbstractStreamOperator

This method is called immediately before any elements are processed, it should contain the operator's initialization logic, e.g. state initialization.

The default implementation does nothing.

Specified by:

open in interface StreamOperator<OUT>

Overrides:

open in class AbstractStreamOperator<OUT>

Throws:

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

processElement

public void processElement(StreamRecord<TimestampedFileInputSplit> element)
                    throws Exception

Description copied from interface: OneInputStreamOperator

Processes one element that arrived at this operator. This method is guaranteed to not be called concurrently with other methods of the operator.

Specified by:

processElement in interface OneInputStreamOperator<TimestampedFileInputSplit,OUT>

Throws:

Exception

processWatermark

public void processWatermark(Watermark mark)
                      throws Exception

Description copied from interface: OneInputStreamOperator

Processes a Watermark. This method is guaranteed to not be called concurrently with other methods of the operator.

Specified by:

processWatermark in interface OneInputStreamOperator<TimestampedFileInputSplit,OUT>

Overrides:

processWatermark in class AbstractStreamOperator<OUT>

Throws:

Exception

See Also:

Watermark

dispose

public void dispose()
             throws Exception

Description copied from class: AbstractStreamOperator

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.

Specified by:

dispose in interface StreamOperator<OUT>

Specified by:

dispose in interface org.apache.flink.util.Disposable

Overrides:

dispose in class AbstractStreamOperator<OUT>

Throws:

Exception

close

public void close()
           throws Exception

Description copied from class: AbstractStreamOperator

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).

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.

Specified by:

close in interface StreamOperator<OUT>

Overrides:

close in class AbstractStreamOperator<OUT>

Throws:

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

snapshotState

public void snapshotState(org.apache.flink.runtime.state.StateSnapshotContext context)
                   throws Exception

Description copied from class: AbstractStreamOperator

Stream operators with state, which want to participate in a snapshot need to override this hook method.

Overrides:

snapshotState in class AbstractStreamOperator<OUT>

Parameters:

context - context that provides information and means required for taking a snapshot

Throws:

Exception