org.apache.flink.streaming.runtime.operators

类 GenericWriteAheadSink<IN>

java.lang.Object

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

org.apache.flink.streaming.runtime.operators.GenericWriteAheadSink<IN>

类型参数:

IN - Type of the elements emitted by this sink

所有已实现的接口:

Serializable, org.apache.flink.runtime.state.CheckpointListener, KeyContext, OneInputStreamOperator<IN,IN>, SetupableStreamOperator<IN>, StreamOperator<IN>, StreamOperatorStateHandler.CheckpointedStreamOperator, org.apache.flink.util.Disposable

public abstract class GenericWriteAheadSink<IN>
extends AbstractStreamOperator<IN>
implements OneInputStreamOperator<IN,IN>

Generic Sink that emits its input elements into an arbitrary backend. This sink is integrated with Flink's checkpointing mechanism and can provide exactly-once guarantees; depending on the storage backend and sink/committer implementation.

Incoming records are stored within a AbstractStateBackend, and only committed if a checkpoint is completed.

另请参阅:

序列化表格

字段概要

字段

限定符和类型	字段和说明
protected static org.slf4j.Logger	LOG
protected org.apache.flink.api.common.typeutils.TypeSerializer<IN>	serializer

从类继承的字段 org.apache.flink.streaming.api.operators.AbstractStreamOperator

chainingStrategy, config, latencyStats, metrics, output, processingTimeService

构造器概要

构造器

构造器和说明
GenericWriteAheadSink(CheckpointCommitter committer, org.apache.flink.api.common.typeutils.TypeSerializer<IN> serializer, String jobID)

方法概要

限定符和类型	方法和说明
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	initializeState(org.apache.flink.runtime.state.StateInitializationContext context) Stream operators with state which can be restored need to override this hook method.
void	notifyCheckpointComplete(long checkpointId)
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<IN> element) Processes one element that arrived at this operator.
protected abstract boolean	sendValues(Iterable<IN> values, long checkpointId, long timestamp) Write the given element into the backend.
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.

从类继承的方法 org.apache.flink.streaming.api.operators.AbstractStreamOperator

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

从类继承的方法 java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

从接口继承的方法 org.apache.flink.streaming.api.operators.OneInputStreamOperator

processLatencyMarker, processWatermark

从接口继承的方法 org.apache.flink.streaming.api.operators.StreamOperator

dispose, getMetricGroup, getOperatorID, initializeState, prepareSnapshotPreBarrier, setKeyContextElement1, setKeyContextElement2, snapshotState

从接口继承的方法 org.apache.flink.runtime.state.CheckpointListener

notifyCheckpointAborted

从接口继承的方法 org.apache.flink.streaming.api.operators.KeyContext

getCurrentKey, setCurrentKey

字段详细资料

LOG

protected static final org.slf4j.Logger LOG

serializer

protected final org.apache.flink.api.common.typeutils.TypeSerializer<IN> serializer

构造器详细资料

GenericWriteAheadSink

public GenericWriteAheadSink(CheckpointCommitter committer,
                             org.apache.flink.api.common.typeutils.TypeSerializer<IN> serializer,
                             String jobID)
                      throws Exception

抛出:

Exception

方法详细资料

initializeState

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

从类复制的说明: AbstractStreamOperator

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

指定者:

initializeState 在接口中 StreamOperatorStateHandler.CheckpointedStreamOperator

覆盖:

initializeState 在类中 AbstractStreamOperator<IN>

参数:

context - context that allows to register different states.

抛出:

Exception

open

public void open()
          throws Exception

从类复制的说明: 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.

指定者:

open 在接口中 StreamOperator<IN>

覆盖:

open 在类中 AbstractStreamOperator<IN>

抛出:

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

close

public void close()
           throws Exception

从类复制的说明: 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.

指定者:

close 在接口中 StreamOperator<IN>

覆盖:

close 在类中 AbstractStreamOperator<IN>

抛出:

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

snapshotState

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

从类复制的说明: AbstractStreamOperator

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

指定者:

snapshotState 在接口中 StreamOperatorStateHandler.CheckpointedStreamOperator

覆盖:

snapshotState 在类中 AbstractStreamOperator<IN>

参数:

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

抛出:

Exception

notifyCheckpointComplete

public void notifyCheckpointComplete(long checkpointId)
                              throws Exception

指定者:

notifyCheckpointComplete 在接口中 org.apache.flink.runtime.state.CheckpointListener

覆盖:

notifyCheckpointComplete 在类中 AbstractStreamOperator<IN>

抛出:

Exception

sendValues

protected abstract boolean sendValues(Iterable<IN> values,
                                      long checkpointId,
                                      long timestamp)
                               throws Exception

Write the given element into the backend.

参数:

values - The values to be written

checkpointId - The checkpoint ID of the checkpoint to be written

timestamp - The wall-clock timestamp of the checkpoint

返回:

true, if the sending was successful, false otherwise

抛出:

Exception

processElement

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

从接口复制的说明: OneInputStreamOperator

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

指定者:

processElement 在接口中 OneInputStreamOperator<IN,IN>

抛出:

Exception