org.apache.flink.streaming.connectors.gcp.pubsub.common

类 AcknowledgeOnCheckpoint<ACKID extends Serializable>

java.lang.Object

org.apache.flink.streaming.connectors.gcp.pubsub.common.AcknowledgeOnCheckpoint<ACKID>

类型参数:

ACKID - Type of Ids to acknowledge

所有已实现的接口:

org.apache.flink.runtime.state.CheckpointListener, org.apache.flink.streaming.api.checkpoint.ListCheckpointed<AcknowledgeIdsForCheckpoint<ACKID>>

public class AcknowledgeOnCheckpoint<ACKID extends Serializable>
extends Object
implements org.apache.flink.runtime.state.CheckpointListener, org.apache.flink.streaming.api.checkpoint.ListCheckpointed<AcknowledgeIdsForCheckpoint<ACKID>>

Helper class for SourceFunctions to acknowledge messages to external systems after a successful checkpoint.

The mechanism for this source assumes that messages are identified by a unique ID. When messages are taken from the message queue, the message must not be dropped immediately from the external system, but must be retained until acknowledged. Messages that are not acknowledged within a certain time interval will be served again (to a different connection, established by the recovered source).

Note that this source can give no guarantees about message order in the case of failures, because messages that were retrieved but not yet acknowledged will be returned later again, after a set of messages that was not retrieved before the failure.

Internally, this class gathers the IDs of elements it emits. Per checkpoint, the IDs are stored and acknowledged when the checkpoint is complete. That way, no message is acknowledged unless it is certain that it has been successfully processed throughout the topology and the updates to any state caused by that message are persistent.

构造器概要

构造器

构造器和说明
AcknowledgeOnCheckpoint(Acknowledger<ACKID> acknowledger)

方法概要

限定符和类型	方法和说明
void	addAcknowledgeId(ACKID id)
void	notifyCheckpointAborted(long checkpointId)
void	notifyCheckpointComplete(long checkpointId)
int	numberOfOutstandingAcknowledgements()
void	restoreState(List<AcknowledgeIdsForCheckpoint<ACKID>> state)
List<AcknowledgeIdsForCheckpoint<ACKID>>	snapshotState(long checkpointId, long timestamp)

从类继承的方法 java.lang.Object

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

构造器详细资料

AcknowledgeOnCheckpoint

public AcknowledgeOnCheckpoint(Acknowledger<ACKID> acknowledger)

方法详细资料

addAcknowledgeId

public void addAcknowledgeId(ACKID id)

notifyCheckpointComplete

public void notifyCheckpointComplete(long checkpointId)
                              throws Exception

指定者:

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

抛出:

Exception

notifyCheckpointAborted

public void notifyCheckpointAborted(long checkpointId)

指定者:

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

snapshotState

public List<AcknowledgeIdsForCheckpoint<ACKID>> snapshotState(long checkpointId,
                                                              long timestamp)
                                                       throws Exception

指定者:

snapshotState 在接口中 org.apache.flink.streaming.api.checkpoint.ListCheckpointed<AcknowledgeIdsForCheckpoint<ACKID extends Serializable>>

抛出:

Exception

restoreState

public void restoreState(List<AcknowledgeIdsForCheckpoint<ACKID>> state)
                  throws Exception

指定者:

restoreState 在接口中 org.apache.flink.streaming.api.checkpoint.ListCheckpointed<AcknowledgeIdsForCheckpoint<ACKID extends Serializable>>

抛出:

Exception

numberOfOutstandingAcknowledgements

public int numberOfOutstandingAcknowledgements()