com.amazonaws.services.kinesis.clientlibrary.lib.worker

Class PrefetchGetRecordsCache

java.lang.Object

com.amazonaws.services.kinesis.clientlibrary.lib.worker.PrefetchGetRecordsCache

All Implemented Interfaces:

GetRecordsCache

public class PrefetchGetRecordsCache
extends Object
implements GetRecordsCache

This is the prefetch caching class, this class spins up a thread if prefetching is enabled. That thread fetches the next set of records and stores it in the cache. The size of the cache is limited by setting maxPendingProcessRecordsInput i.e. the maximum number of GetRecordsResult that the cache can store, maxByteSize i.e. the byte size of the records stored in the cache and maxRecordsCount i.e. the max number of records that should be present in the cache across multiple GetRecordsResult object. If no data is available in the cache, the call from the record processor is blocked till records are retrieved from Kinesis.

Constructor Summary

Constructors

Constructor and Description
PrefetchGetRecordsCache(int maxPendingProcessRecordsInput, int maxByteSize, int maxRecordsCount, int maxRecordsPerCall, @NonNull GetRecordsRetrievalStrategy getRecordsRetrievalStrategy, @NonNull ExecutorService executorService, long idleMillisBetweenCalls, @NonNull IMetricsFactory metricsFactory, @NonNull String operation, @NonNull String shardId) Constructor for the PrefetchGetRecordsCache.

Method Summary

Modifier and Type	Method and Description
GetRecordsRetrievalStrategy	getGetRecordsRetrievalStrategy()
ProcessRecordsInput	getNextResult() This method returns the next set of records from the Cache if present, or blocks the request till it gets the next set of records back from Kinesis.
void	shutdown() This method calls the shutdown behavior on the cache, if available.
void	start() This method calls the start behavior on the cache, if available.

Methods inherited from class java.lang.Object

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

Constructor Detail

PrefetchGetRecordsCache

public PrefetchGetRecordsCache(int maxPendingProcessRecordsInput,
                               int maxByteSize,
                               int maxRecordsCount,
                               int maxRecordsPerCall,
                               @NonNull
                               @NonNull GetRecordsRetrievalStrategy getRecordsRetrievalStrategy,
                               @NonNull
                               @NonNull ExecutorService executorService,
                               long idleMillisBetweenCalls,
                               @NonNull
                               @NonNull IMetricsFactory metricsFactory,
                               @NonNull
                               @NonNull String operation,
                               @NonNull
                               @NonNull String shardId)

Constructor for the PrefetchGetRecordsCache. This cache prefetches records from Kinesis and stores them in a LinkedBlockingQueue.

Parameters:

maxPendingProcessRecordsInput - Max number of ProcessRecordsInput that can be held in the cache before blocking

maxByteSize - Max byte size of the queue before blocking next get records call

maxRecordsCount - Max number of records in the queue across all ProcessRecordInput objects

maxRecordsPerCall - Max records to be returned per call

getRecordsRetrievalStrategy - Retrieval strategy for the get records call

executorService - Executor service for the cache

idleMillisBetweenCalls - maximum time to wait before dispatching the next get records call

See Also:

PrefetchGetRecordsCache

Method Detail

start

public void start()

Description copied from interface: GetRecordsCache

This method calls the start behavior on the cache, if available.

Specified by:

start in interface GetRecordsCache

getNextResult

public ProcessRecordsInput getNextResult()

Description copied from interface: GetRecordsCache

This method returns the next set of records from the Cache if present, or blocks the request till it gets the next set of records back from Kinesis.

Specified by:

getNextResult in interface GetRecordsCache

Returns:

The next set of records.

getGetRecordsRetrievalStrategy

public GetRecordsRetrievalStrategy getGetRecordsRetrievalStrategy()

Specified by:

getGetRecordsRetrievalStrategy in interface GetRecordsCache

shutdown

public void shutdown()

Description copied from interface: GetRecordsCache

This method calls the shutdown behavior on the cache, if available.

Specified by:

shutdown in interface GetRecordsCache