Package io.jenetics.util

Class StreamPublisher<T>

java.lang.Object

java.util.concurrent.SubmissionPublisher<T>

io.jenetics.util.StreamPublisher<T>

Type Parameters:

T - the element type of the publisher

All Implemented Interfaces:

AutoCloseable, Flow.Publisher<T>

public class StreamPublisher<T>
extends SubmissionPublisher<T>

This class allows to create a reactive Flow.Publisher from a given Java Stream.

final Stream<Long> stream = engine.stream() .limit(33) .map(EvolutionResult::generation); try (var publisher = new StreamPublisher<Long>()) { publisher.subscribe(new Subscriber<>() { private Subscription subscription; @Override public void onSubscribe(final Subscription subscription) { this.subscription = subscription; this.subscription.request(1); } @Override public void onNext(final Long g) { System.out.println("Got new generation: " + g); subscription.request(1); } @Override public void onError(final Throwable throwable) { } @Override public void onComplete() { System.out.println("Evolution completed."); } }); // Attaching the stream, starts the element publishing. publisher.attach(stream); ... }

Since:

6.0

Version:

6.0

Author:

Franz Wilhelmstötter

Constructor Summary

Constructors

Constructor	Description
StreamPublisher()	Creates a new publisher using the ForkJoinPool.commonPool() for async delivery to subscribers (unless it does not support a parallelism level of at least two, in which case, a new Thread is created to run each task), with maximum buffer capacity of Flow.defaultBufferSize(), and no handler for Subscriber exceptions in method onNext.
StreamPublisher(Executor executor, int maxBufferCapacity)	Creates a new StreamPublisher using the given Executor for async delivery to subscribers, with the given maximum buffer size for each subscriber, and no handler for Subscriber exceptions in method Flow.Subscriber.onNext(Object).
StreamPublisher(Executor executor, int maxBufferCapacity, BiConsumer<? super Flow.Subscriber<? super T>,? super Throwable> handler)	Creates a new StreamPublisher using the given Executor for async delivery to subscribers, with the given maximum buffer size for each subscriber.

Method Summary

Modifier and Type	Method	Description
void	attach(Stream<? extends T> stream)	Attaches the given stream to the publisher.
void	close()	Unless already closed, issues onComplete signals to current subscribers, and disallows subsequent attempts to publish.

Methods inherited from class java.util.concurrent.SubmissionPublisher

closeExceptionally, consume, estimateMaximumLag, estimateMinimumDemand, getClosedException, getExecutor, getMaxBufferCapacity, getNumberOfSubscribers, getSubscribers, hasSubscribers, isClosed, isSubscribed, offer, offer, submit, subscribe

Methods inherited from class java.lang.Object

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

Constructor Detail

StreamPublisher

public StreamPublisher(Executor executor,
                       int maxBufferCapacity,
                       BiConsumer<? super Flow.Subscriber<? super T>,? super Throwable> handler)

Creates a new StreamPublisher using the given Executor for async delivery to subscribers, with the given maximum buffer size for each subscriber.

Parameters:

executor - the executor to use for async delivery, supporting creation of at least one independent thread

maxBufferCapacity - the maximum capacity for each subscriber's buffer

handler - if non-null, procedure to invoke upon exception thrown in method onNext

Throws:

NullPointerException - if one of the arguments is null

IllegalArgumentException - if maxBufferCapacity not positive

StreamPublisher

public StreamPublisher(Executor executor,
                       int maxBufferCapacity)

Creates a new StreamPublisher using the given Executor for async delivery to subscribers, with the given maximum buffer size for each subscriber, and no handler for Subscriber exceptions in method Flow.Subscriber.onNext(Object).

Parameters:

executor - the executor to use for async delivery, supporting creation of at least one independent thread

maxBufferCapacity - the maximum capacity for each subscriber's buffer

Throws:

NullPointerException - if the given executor is null

IllegalArgumentException - if maxBufferCapacity not positive

StreamPublisher

public StreamPublisher()

Creates a new publisher using the ForkJoinPool.commonPool() for async delivery to subscribers (unless it does not support a parallelism level of at least two, in which case, a new Thread is created to run each task), with maximum buffer capacity of Flow.defaultBufferSize(), and no handler for Subscriber exceptions in method onNext.

Method Detail

attach

public void attach(Stream<? extends T> stream)

Attaches the given stream to the publisher. This method automatically starts the publishing of the elements read from the stream.

Parameters:

stream - the stream to attach

Throws:

NullPointerException - if the given stream is null

IllegalStateException - if a stream is already attached to this publisher

close

public void close()

Unless already closed, issues onComplete signals to current subscribers, and disallows subsequent attempts to publish. Upon return, this method does NOT guarantee that all subscribers have yet completed.

Specified by:

close in interface AutoCloseable

Overrides:

close in class SubmissionPublisher<T>