org.glassfish.jersey.internal.util

Class JerseyPublisher<T>

java.lang.Object

org.glassfish.jersey.internal.util.JerseyPublisher<T>

All Implemented Interfaces:

Flow.Publisher<T>

public class JerseyPublisher<T>
extends Object
implements Flow.Publisher<T>

Implementation of Flow.Publisher corresponding to reactive streams specification.

Delegates to SubmissionPublisher repackaged from jsr166 on JDK 8 or to JDK SubmissionPublisher.

Author:

Adam Lindenthal

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static class	JerseyPublisher.PublisherStrategy
class	JerseyPublisher.SubscriberWrapper<T>

Constructor Summary

Constructors

Constructor and Description
JerseyPublisher() Creates a new JerseyPublisher 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 and default JerseyPublisher.PublisherStrategy, which is JerseyPublisher.PublisherStrategy.BEST_EFFORT.
JerseyPublisher(Executor executor) Creates a new JerseyPublisher using the given Executor for async delivery to subscribers, with the default maximum buffer size of and default JerseyPublisher.PublisherStrategy, which is JerseyPublisher.PublisherStrategy.BEST_EFFORT.
JerseyPublisher(Executor executor, int maxBufferCapacity, JerseyPublisher.PublisherStrategy strategy) Creates a new JerseyPublisher using the given Executor for async delivery to subscribers, with the given maximum buffer size for each subscriber and given JerseyPublisher.PublisherStrategy.
JerseyPublisher(Executor executor, JerseyPublisher.PublisherStrategy strategy) Creates a new JerseyPublisher using the given Executor for async delivery to subscribers, with the default maximum buffer size of and given JerseyPublisher.PublisherStrategy.
JerseyPublisher(int maxBufferCapacity) Creates a new JerseyPublisher 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 specified maximum buffer capacity and default JerseyPublisher.PublisherStrategy, which is JerseyPublisher.PublisherStrategy.BEST_EFFORT.
JerseyPublisher(JerseyPublisher.PublisherStrategy strategy) Creates a new JerseyPublisher 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 and given JerseyPublisher.PublisherStrategy.

Method Summary

Modifier and Type	Method and Description
void	close() Unless already closed, issues onComplete() signals to current subscribers, and disallows subsequent attempts to publish.
void	close(boolean cascading) Same as close() but with control as to whether registered subscribers should be closed or not.
void	closeExceptionally(Throwable error) Issues onError signals to current subscribers with the given error, and disallows subsequent attempts to publish.
CompletableFuture<Void>	consume(Consumer<? super T> consumer) Processes all published items using the given Consumer function.
int	estimateMaximumLag() Returns an estimate of the maximum number of items produced but not yet consumed among all current subscribers.
long	estimateMinimumDemand() Returns an estimate of the minimum number of items requested but not yet produced, among all current subscribers.
Throwable	getClosedException() Returns the exception associated with closeExceptionally(java.lang.Throwable), or null if not closed or if closed normally.
int	getMaxBufferCapacity() Returns the maximum per-subscriber buffer capacity.
int	publish(T item) Publishes the given item to all current subscribers by invoking its onNext() method using Executor provided as constructor parameter (or the default Executor if not provided).
void	subscribe(Flow.Subscriber<? super T> subscriber) Adds the given Subscriber if possible.

Methods inherited from class java.lang.Object

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

Constructor Detail

JerseyPublisher

public JerseyPublisher()

Creates a new JerseyPublisher 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 and default JerseyPublisher.PublisherStrategy, which is JerseyPublisher.PublisherStrategy.BEST_EFFORT.

JerseyPublisher

public JerseyPublisher(JerseyPublisher.PublisherStrategy strategy)

Creates a new JerseyPublisher 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 and given JerseyPublisher.PublisherStrategy.

Parameters:

strategy - publisher delivering strategy

JerseyPublisher

public JerseyPublisher(Executor executor)

Creates a new JerseyPublisher using the given Executor for async delivery to subscribers, with the default maximum buffer size of and default JerseyPublisher.PublisherStrategy, which is JerseyPublisher.PublisherStrategy.BEST_EFFORT.

Parameters:

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

Throws:

NullPointerException - if executor is null

IllegalArgumentException - if maxBufferCapacity not positive

JerseyPublisher

public JerseyPublisher(Executor executor,
                       JerseyPublisher.PublisherStrategy strategy)

Creates a new JerseyPublisher using the given Executor for async delivery to subscribers, with the default maximum buffer size of and given JerseyPublisher.PublisherStrategy.

Parameters:

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

strategy - publisher delivering strategy

Throws:

NullPointerException - if executor is null

IllegalArgumentException - if maxBufferCapacity not positive

JerseyPublisher

public JerseyPublisher(int maxBufferCapacity)

Creates a new JerseyPublisher 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 specified maximum buffer capacity and default JerseyPublisher.PublisherStrategy, which is JerseyPublisher.PublisherStrategy.BEST_EFFORT.

Parameters:

maxBufferCapacity - the maximum capacity for each subscriber's buffer (the enforced capacity may be rounded up to the nearest power of two and/or bounded by the largest value supported by this implementation; method getMaxBufferCapacity() returns the actual value)

JerseyPublisher

public JerseyPublisher(Executor executor,
                       int maxBufferCapacity,
                       JerseyPublisher.PublisherStrategy strategy)

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

Parameters:

executor - 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 (the enforced capacity may be rounded up to the nearest power of two and/or bounded by the largest value supported by this implementation; method getMaxBufferCapacity() returns the actual value)

strategy - publisher delivering strategy

Throws:

NullPointerException - if executor is null

IllegalArgumentException - if maxBufferCapacity not positive

Method Detail

subscribe

public void subscribe(Flow.Subscriber<? super T> subscriber)

Description copied from interface: Flow.Publisher

Adds the given Subscriber if possible. If already subscribed, or the attempt to subscribe fails due to policy violations or errors, the Subscriber's onError method is invoked with an IllegalStateException. Otherwise, the Subscriber's onSubscribe method is invoked with a new Flow.Subscription. Subscribers may enable receiving items by invoking the request method of this Subscription, and may unsubscribe by invoking its cancel method.

Specified by:

subscribe in interface Flow.Publisher<T>

Parameters:

subscriber - the subscriber

consume

public CompletableFuture<Void> consume(Consumer<? super T> consumer)

Processes all published items using the given Consumer function. Returns a CompletableFuture that is completed normally when this publisher signals onComplete(), or completed exceptionally upon any error, or an exception is thrown by the Consumer, or the returned CompletableFuture is cancelled, in which case no further items are processed.

Parameters:

consumer - function to process all published data

Returns:

a CompletableFuture that is completed normally when the publisher signals onComplete, and exceptionally upon any error or cancellation

Throws:

NullPointerException - if consumer is null

publish

public int publish(T item)

Publishes the given item to all current subscribers by invoking its onNext() method using Executor provided as constructor parameter (or the default Executor if not provided).

Concrete behaviour is specified by JerseyPublisher.PublisherStrategy selected upon JerseyPublisher creation.

Parameters:

item - the (non-null) item to publish.

Returns:

if negative, the (negative) number of drops; otherwise an estimate of maximum lag.

Throws:

IllegalStateException - if closed

NullPointerException - if item is null

RejectedExecutionException - if thrown by Executor

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.

close

public void close(boolean cascading)

Same as close() but with control as to whether registered subscribers should be closed or not.

Parameters:

cascading - Boolean controlling whether to close subscribers or not.

closeExceptionally

public void closeExceptionally(Throwable error)

Issues onError signals to current subscribers with the given error, and disallows subsequent attempts to publish.

Parameters:

error - the onError argument sent to subscribers

Throws:

NullPointerException - if error is null

estimateMaximumLag

public int estimateMaximumLag()

Returns an estimate of the maximum number of items produced but not yet consumed among all current subscribers.

Returns:

estimated maximum lag

estimateMinimumDemand

public long estimateMinimumDemand()

Returns an estimate of the minimum number of items requested but not yet produced, among all current subscribers.

Returns:

estimated minimum demand

getClosedException

public Throwable getClosedException()

Returns the exception associated with closeExceptionally(java.lang.Throwable), or null if not closed or if closed normally.

Returns:

exception thrown on closing or null

getMaxBufferCapacity

public int getMaxBufferCapacity()

Returns the maximum per-subscriber buffer capacity.

Returns:

the maximum per-subscriber buffer capacity