org.apache.kafka.streams.processor

Class AbstractNotifyingRestoreCallback

java.lang.Object

org.apache.kafka.streams.processor.AbstractNotifyingRestoreCallback

All Implemented Interfaces:

StateRestoreCallback, StateRestoreListener

public abstract class AbstractNotifyingRestoreCallback
extends Object
implements StateRestoreCallback, StateRestoreListener

Abstract implementation of the StateRestoreCallback used for batch restoration operations. Includes default no-op methods of the StateRestoreListener StateRestoreListener.onRestoreStart(TopicPartition, String, long, long), StateRestoreListener.onBatchRestored(TopicPartition, String, long, long), and StateRestoreListener.onRestoreEnd(TopicPartition, String, long).

Constructor Summary

Constructors

Constructor and Description
AbstractNotifyingRestoreCallback()

Method Summary

Modifier and Type	Method and Description
void	onBatchRestored(TopicPartition topicPartition, String storeName, long batchEndOffset, long numRestored) Method called after restoring a batch of records.
void	onRestoreEnd(TopicPartition topicPartition, String storeName, long totalRestored) Method called when restoring the StateStore is complete.
void	onRestoreStart(TopicPartition topicPartition, String storeName, long startingOffset, long endingOffset) Method called at the very beginning of StateStore restoration.

Methods inherited from class java.lang.Object

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

Methods inherited from interface org.apache.kafka.streams.processor.StateRestoreCallback

restore

Constructor Detail

AbstractNotifyingRestoreCallback

public AbstractNotifyingRestoreCallback()

Method Detail

onRestoreStart

public void onRestoreStart(TopicPartition topicPartition,
                           String storeName,
                           long startingOffset,
                           long endingOffset)

Description copied from interface: StateRestoreListener

Method called at the very beginning of StateStore restoration.

Specified by:

onRestoreStart in interface StateRestoreListener

Parameters:

topicPartition - the TopicPartition containing the values to restore

storeName - the name of the store undergoing restoration

startingOffset - the starting offset of the entire restoration process for this TopicPartition

endingOffset - the ending offset of the entire restoration process for this TopicPartition

See Also:

This method does nothing by default; if desired, subclasses should override it with custom functionality.

onBatchRestored

public void onBatchRestored(TopicPartition topicPartition,
                            String storeName,
                            long batchEndOffset,
                            long numRestored)

Description copied from interface: StateRestoreListener

Method called after restoring a batch of records. In this case the maximum size of the batch is whatever the value of the MAX_POLL_RECORDS is set to. This method is called after restoring each batch and it is advised to keep processing to a minimum. Any heavy processing will hold up recovering the next batch, hence slowing down the restore process as a whole. If you need to do any extended processing or connecting to an external service consider doing so asynchronously.

Specified by:

onBatchRestored in interface StateRestoreListener

Parameters:

topicPartition - the TopicPartition containing the values to restore

storeName - the name of the store undergoing restoration

batchEndOffset - the ending offset for the current restored batch for this TopicPartition

numRestored - the total number of records restored in this batch for this TopicPartition

See Also:

This method does nothing by default; if desired, subclasses should override it with custom functionality.

onRestoreEnd

public void onRestoreEnd(TopicPartition topicPartition,
                         String storeName,
                         long totalRestored)

Description copied from interface: StateRestoreListener

Method called when restoring the StateStore is complete.

Specified by:

onRestoreEnd in interface StateRestoreListener

Parameters:

topicPartition - the TopicPartition containing the values to restore

storeName - the name of the store just restored

totalRestored - the total number of records restored for this TopicPartition

See Also:

This method does nothing by default; if desired, subclasses should override it with custom functionality.