Package org.hibernate.search.engine.backend.orchestration.spi

Class BatchingExecutor<P extends BatchedWorkProcessor,W extends BatchedWork<? super P>>

java.lang.Object

org.hibernate.search.engine.backend.orchestration.spi.BatchingExecutor<P,W>

public final class BatchingExecutor<P extends BatchedWorkProcessor,W extends BatchedWork<? super P>>
extends Object

An executor of works that accepts works from multiple threads, puts them in a queue, and processes them in batches in a single background thread.

Useful when works can be merged together for optimization purposes (bulking in Elasticsearch), or when they should never be executed in parallel (writes to a Lucene index).

Constructor Summary

Constructors

Constructor	Description
BatchingExecutor(String name, P processor, int maxTasksPerBatch, boolean fair, FailureHandler failureHandler, Consumer<? super W> blockingRetryProducer)

Method Summary

Modifier and Type	Method	Description
CompletableFuture<?>	completion()
void	start(SimpleScheduledExecutor executorService)	Start the executor, allowing works to be submitted through submit(BatchedWork, OperationSubmitter).
void	stop()	Stop the executor, no longer allowing works to be submitted through submit(BatchedWork, OperationSubmitter).
void	submit(W work)	Deprecated. Use submit(BatchedWork, OperationSubmitter) instead.
void	submit(W work, OperationSubmitter operationSubmitter)	Submit a work for execution.
String	toString()

Methods inherited from class java.lang.Object

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

Constructor Details

BatchingExecutor

public BatchingExecutor(String name,
 P processor,
 int maxTasksPerBatch,
 boolean fair,
 FailureHandler failureHandler,
 Consumer<? super W> blockingRetryProducer)

Parameters:

name - The name of the executor thread (and of this executor when reporting errors)

processor - A task processor. May not be thread-safe.

maxTasksPerBatch - The maximum number of tasks to process in a single batch. Higher values mean more opportunity for the processor to optimize execution, but higher heap consumption.

fair - if true tasks are always submitted to the processor in FIFO order, if false tasks submitted when the internal queue is full may be submitted out of order.

failureHandler - A failure handler to report failures of the background thread.

blockingRetryProducer - A retry work producer that would be called in case of offloading operation submitter and full queue.

Method Details

toString

public String toString()

Overrides:

toString in class Object

start

public void start(SimpleScheduledExecutor executorService)

Start the executor, allowing works to be submitted through submit(BatchedWork, OperationSubmitter).

Parameters:

executorService - An executor service with at least one thread.

stop

public void stop()

Stop the executor, no longer allowing works to be submitted through submit(BatchedWork, OperationSubmitter).

This will remove pending works from the queue.

submit

@Deprecated
public void submit(W work)
            throws InterruptedException

Deprecated.

Use submit(BatchedWork, OperationSubmitter) instead.

Throws:

InterruptedException

submit

public void submit(W work,
 OperationSubmitter operationSubmitter)
            throws InterruptedException

Submit a work for execution.

Must not be called when the executor is stopped.

Parameters:

work - A work to execute.

operationSubmitter - How to handle request to submit operation when the queue is full.

Throws:

InterruptedException - If the current thread is interrupted while enqueuing the work.

completion

public CompletableFuture<?> completion()

Returns:

A future that completes when all works submitted to the executor so far are completely executed. Works submitted to the executor after entering this method may delay the wait.