IN - Type of the elements emitted by this sinkpublic abstract class GenericWriteAheadSink<IN> extends AbstractStreamOperator<IN> implements OneInputStreamOperator<IN,IN>
Incoming records are stored within a AbstractStateBackend, and only committed if a checkpoint is
completed.
| Modifier and Type | Field and Description |
|---|---|
protected static org.slf4j.Logger |
LOG |
protected TypeSerializer<IN> |
serializer |
chainingStrategy, config, latencyStats, metrics, output, processingTimeService| Constructor and Description |
|---|
GenericWriteAheadSink(CheckpointCommitter committer,
TypeSerializer<IN> serializer,
String jobID) |
| 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 |
initializeState(StateInitializationContext context)
Stream operators with state which can be restored need to override this hook method.
|
void |
notifyCheckpointComplete(long checkpointId)
Notifies the listener that the checkpoint with the given
checkpointId completed and
was committed. |
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<IN> element)
Processes one element that arrived on this input of the
MultipleInputStreamOperator. |
protected abstract boolean |
sendValues(Iterable<IN> values,
long checkpointId,
long timestamp)
Write the given element into the backend.
|
void |
snapshotState(StateSnapshotContext context)
Stream operators with state, which want to participate in a snapshot need to override this
hook method.
|
finish, getChainingStrategy, getContainingTask, getCurrentKey, getExecutionConfig, getInternalTimerService, getKeyedStateBackend, getKeyedStateStore, getMetricGroup, getOperatorConfig, getOperatorID, getOperatorName, getOperatorStateBackend, getOrCreateKeyedState, getPartitionedState, getPartitionedState, getProcessingTimeService, getRuntimeContext, getTimeServiceManager, getUserCodeClassloader, hasKeyContext1, hasKeyContext2, initializeState, isUsingCustomRawKeyedState, notifyCheckpointAborted, prepareSnapshotPreBarrier, processLatencyMarker, processLatencyMarker1, processLatencyMarker2, processWatermark, processWatermark1, processWatermark2, processWatermarkStatus, processWatermarkStatus1, processWatermarkStatus2, reportOrForwardLatencyMarker, setChainingStrategy, setCurrentKey, setKeyContextElement1, setKeyContextElement2, setProcessingTimeService, setup, snapshotStateclone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, waitsetKeyContextElementfinish, getMetricGroup, getOperatorID, initializeState, prepareSnapshotPreBarrier, setKeyContextElement1, setKeyContextElement2, snapshotStatenotifyCheckpointAbortedgetCurrentKey, setCurrentKeyprocessLatencyMarker, processWatermark, processWatermarkStatushasKeyContextprotected static final org.slf4j.Logger LOG
protected final TypeSerializer<IN> serializer
public GenericWriteAheadSink(CheckpointCommitter committer, TypeSerializer<IN> serializer, String jobID) throws Exception
Exceptionpublic void initializeState(StateInitializationContext context) throws Exception
AbstractStreamOperatorinitializeState in interface StreamOperatorStateHandler.CheckpointedStreamOperatorinitializeState in class AbstractStreamOperator<IN>context - context that allows to register different states.Exceptionpublic void open()
throws Exception
AbstractStreamOperatorThe default implementation does nothing.
open in interface StreamOperator<IN>open in class AbstractStreamOperator<IN>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<IN>close in class AbstractStreamOperator<IN>Exceptionpublic void snapshotState(StateSnapshotContext context) throws Exception
AbstractStreamOperatorsnapshotState in interface StreamOperatorStateHandler.CheckpointedStreamOperatorsnapshotState in class AbstractStreamOperator<IN>context - context that provides information and means required for taking a snapshotExceptionpublic void notifyCheckpointComplete(long checkpointId)
throws Exception
CheckpointListenercheckpointId completed and
was committed.
These notifications are "best effort", meaning they can sometimes be skipped. To behave
properly, implementers need to follow the "Checkpoint Subsuming Contract". Please see the
class-level JavaDocs for details.
Please note that checkpoints may generally overlap, so you cannot assume that the notifyCheckpointComplete() call is always for the latest prior checkpoint (or snapshot) that
was taken on the function/operator implementing this interface. It might be for a checkpoint
that was triggered earlier. Implementing the "Checkpoint Subsuming Contract" (see above)
properly handles this situation correctly as well.
Please note that throwing exceptions from this method will not cause the completed checkpoint to be revoked. Throwing exceptions will typically cause task/job failure and trigger recovery.
notifyCheckpointComplete in interface CheckpointListenernotifyCheckpointComplete in class AbstractStreamOperator<IN>checkpointId - The ID of the checkpoint that has been completed.Exception - This method can propagate exceptions, which leads to a failure/recovery for
the task. Note that this will NOT lead to the checkpoint being revoked.protected abstract boolean sendValues(Iterable<IN> values, long checkpointId, long timestamp) throws Exception
values - The values to be writtencheckpointId - The checkpoint ID of the checkpoint to be writtentimestamp - The wall-clock timestamp of the checkpointExceptionpublic void processElement(StreamRecord<IN> element) throws Exception
InputMultipleInputStreamOperator.
This method is guaranteed to not be called concurrently with other methods of the operator.processElement in interface Input<IN>ExceptionCopyright © 2014–2024 The Apache Software Foundation. All rights reserved.