Package com.linecorp.armeria.common.stream

Class DeferredStreamMessage<T>

java.lang.Object

com.linecorp.armeria.common.stream.DeferredStreamMessage<T>

Type Parameters:

T - the type of element signaled

All Implemented Interfaces:

StreamMessage<T>, org.reactivestreams.Publisher<T>

Direct Known Subclasses:

DeferredHttpResponse

public class DeferredStreamMessage<T>
extends Object

A StreamMessage whose stream is published later by another StreamMessage. It is useful when your StreamMessage will not be instantiated early.

Constructor Summary

Constructors

Constructor	Description
DeferredStreamMessage()

Method Summary

Modifier and Type	Method	Description
void	abort()	Closes this stream with AbortedStreamException and prevents further subscription.
void	close()	Closes the deferred stream without setting a delegate.
void	close(Throwable cause)	Closes the deferred stream without setting a delegate.
CompletableFuture<Void>	completionFuture()	Returns a CompletableFuture that completes when this stream is complete, either successfully or exceptionally, including cancellation and abortion.
protected EventExecutor	defaultSubscriberExecutor()	Returns the default EventExecutor which will be used when a user subscribes using StreamMessage.subscribe(Subscriber) or StreamMessage.subscribe(Subscriber, SubscriptionOption...).
protected void	delegate(StreamMessage<T> delegate)	Sets the delegate StreamMessage which will actually publish the stream.
CompletableFuture<List<T>>	drainAll()	Subscribes to this StreamMessage and retrieves all elements from it.
CompletableFuture<List<T>>	drainAll(boolean withPooledObjects)	Subscribes to this StreamMessage and retrieves all elements from it.
CompletableFuture<List<T>>	drainAll(SubscriptionOption... options)	Subscribes to this StreamMessage and retrieves all elements from it.
CompletableFuture<List<T>>	drainAll(EventExecutor executor)	Subscribes to this StreamMessage and retrieves all elements from it.
CompletableFuture<List<T>>	drainAll(EventExecutor executor, boolean withPooledObjects)	Subscribes to this StreamMessage and retrieves all elements from it.
CompletableFuture<List<T>>	drainAll(EventExecutor executor, SubscriptionOption... options)	Subscribes to this StreamMessage and retrieves all elements from it.
boolean	isEmpty()	Returns true if this stream has been closed and did not publish any elements.
boolean	isOpen()	Returns true if this stream is not closed yet.
protected void	onRemoval(T obj)	Invoked after an element is removed from the StreamMessage and before Subscriber.onNext(Object) is invoked.
void	subscribe(org.reactivestreams.Subscriber<? super T> subscriber)	Requests to start streaming data to the specified Subscriber.
void	subscribe(org.reactivestreams.Subscriber<? super T> subscriber, boolean withPooledObjects)	Requests to start streaming data to the specified Subscriber.
void	subscribe(org.reactivestreams.Subscriber<? super T> subscriber, SubscriptionOption... options)	Requests to start streaming data to the specified Subscriber.
void	subscribe(org.reactivestreams.Subscriber<? super T> subscriber, EventExecutor executor)	Requests to start streaming data to the specified Subscriber.
void	subscribe(org.reactivestreams.Subscriber<? super T> subscriber, EventExecutor executor, boolean withPooledObjects)	Requests to start streaming data, invoking the specified Subscriber from the specified Executor.
void	subscribe(org.reactivestreams.Subscriber<? super T> subscriber, EventExecutor executor, SubscriptionOption... options)	Requests to start streaming data to the specified Subscriber.

Methods inherited from class java.lang.Object

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

Methods inherited from interface com.linecorp.armeria.common.stream.StreamMessage

closeFuture, isComplete

Constructor Detail

DeferredStreamMessage

public DeferredStreamMessage()

Method Detail

delegate

protected void delegate(StreamMessage<T> delegate)

Sets the delegate StreamMessage which will actually publish the stream.

Throws:

IllegalStateException - if the delegate has been set already or if close() or close(Throwable) was called already.

close

public void close()

Closes the deferred stream without setting a delegate.

Throws:

IllegalStateException - if the delegate has been set already or if close() or close(Throwable) was called already.

close

public void close(Throwable cause)

Closes the deferred stream without setting a delegate.

Throws:

IllegalStateException - if the delegate has been set already or if close() or close(Throwable) was called already.

isOpen

public boolean isOpen()

Description copied from interface: StreamMessage

Returns true if this stream is not closed yet. Note that a stream may not be complete even if it's closed; a stream is complete when it's fully consumed by a Subscriber.

isEmpty

public boolean isEmpty()

Description copied from interface: StreamMessage

Returns true if this stream has been closed and did not publish any elements. Note that this method will not return true when the stream is open even if it has not published anything so far, because it may publish something later.

abort

public void abort()

Description copied from interface: StreamMessage

Closes this stream with AbortedStreamException and prevents further subscription. A Subscriber that attempts to subscribe to an aborted stream will be notified with an AbortedStreamException via Subscriber.onError(Throwable). Calling this method on a closed or aborted stream has no effect.

subscribe

public final void subscribe(org.reactivestreams.Subscriber<? super T> subscriber)

Description copied from interface: StreamMessage

Requests to start streaming data to the specified Subscriber. If there is a problem subscribing, Subscriber.onError(Throwable) will be invoked with one of the following exceptions:

• IllegalStateException if other Subscriber subscribed to this stream already.
• AbortedStreamException if this stream has been aborted.
• CancelledSubscriptionException if this stream has been cancelled and SubscriptionOption.NOTIFY_CANCELLATION is specified when subscribed.
• Other exceptions that occurred due to an error while retrieving the elements.

Specified by:

subscribe in interface org.reactivestreams.Publisher<T>

Specified by:

subscribe in interface StreamMessage<T>

subscribe

public final void subscribe(org.reactivestreams.Subscriber<? super T> subscriber,
                            boolean withPooledObjects)

Description copied from interface: StreamMessage

Requests to start streaming data to the specified Subscriber. If there is a problem subscribing, Subscriber.onError(Throwable) will be invoked with one of the following exceptions:

• IllegalStateException if other Subscriber subscribed to this stream already.
• AbortedStreamException if this stream has been aborted.
• CancelledSubscriptionException if this stream has been cancelled and SubscriptionOption.NOTIFY_CANCELLATION is specified when subscribed.
• Other exceptions that occurred due to an error while retrieving the elements.

Specified by:

subscribe in interface StreamMessage<T>

subscribe

public final void subscribe(org.reactivestreams.Subscriber<? super T> subscriber,
                            SubscriptionOption... options)

Description copied from interface: StreamMessage

Requests to start streaming data to the specified Subscriber. If there is a problem subscribing, Subscriber.onError(Throwable) will be invoked with one of the following exceptions:

• IllegalStateException if other Subscriber subscribed to this stream already.
• AbortedStreamException if this stream has been aborted.
• CancelledSubscriptionException if this stream has been cancelled and SubscriptionOption.NOTIFY_CANCELLATION is specified when subscribed.
• Other exceptions that occurred due to an error while retrieving the elements.

Specified by:

subscribe in interface StreamMessage<T>

options - SubscriptionOptions to subscribe with

subscribe

public final void subscribe(org.reactivestreams.Subscriber<? super T> subscriber,
                            EventExecutor executor,
                            boolean withPooledObjects)

Description copied from interface: StreamMessage

Requests to start streaming data, invoking the specified Subscriber from the specified Executor. If there is a problem subscribing, Subscriber.onError(Throwable) will be invoked with one of the following exceptions:

• IllegalStateException if other Subscriber subscribed to this stream already.
• AbortedStreamException if this stream has been aborted.
• CancelledSubscriptionException if this stream has been cancelled and SubscriptionOption.NOTIFY_CANCELLATION is specified when subscribed.
• Other exceptions that occurred due to an error while retrieving the elements.

Specified by:

subscribe in interface StreamMessage<T>

executor - the executor to subscribe

subscribe

public final void subscribe(org.reactivestreams.Subscriber<? super T> subscriber,
                            EventExecutor executor)

Description copied from interface: StreamMessage

Requests to start streaming data to the specified Subscriber. If there is a problem subscribing, Subscriber.onError(Throwable) will be invoked with one of the following exceptions:

• IllegalStateException if other Subscriber subscribed to this stream already.
• AbortedStreamException if this stream has been aborted.
• CancelledSubscriptionException if this stream has been cancelled and SubscriptionOption.NOTIFY_CANCELLATION is specified when subscribed.
• Other exceptions that occurred due to an error while retrieving the elements.

Specified by:

subscribe in interface StreamMessage<T>

executor - the executor to subscribe

subscribe

public final void subscribe(org.reactivestreams.Subscriber<? super T> subscriber,
                            EventExecutor executor,
                            SubscriptionOption... options)

Description copied from interface: StreamMessage

Requests to start streaming data to the specified Subscriber. If there is a problem subscribing, Subscriber.onError(Throwable) will be invoked with one of the following exceptions:

• IllegalStateException if other Subscriber subscribed to this stream already.
• AbortedStreamException if this stream has been aborted.
• CancelledSubscriptionException if this stream has been cancelled and SubscriptionOption.NOTIFY_CANCELLATION is specified when subscribed.
• Other exceptions that occurred due to an error while retrieving the elements.

Specified by:

subscribe in interface StreamMessage<T>

executor - the executor to subscribe

options - SubscriptionOptions to subscribe with

defaultSubscriberExecutor

protected EventExecutor defaultSubscriberExecutor()

Returns the default EventExecutor which will be used when a user subscribes using StreamMessage.subscribe(Subscriber) or StreamMessage.subscribe(Subscriber, SubscriptionOption...).

drainAll

public final CompletableFuture<List<T>> drainAll()

Description copied from interface: StreamMessage

Subscribes to this StreamMessage and retrieves all elements from it. The returned CompletableFuture may be completed exceptionally with the following exceptions:

• IllegalStateException if other Subscriber subscribed to this stream already.
• AbortedStreamException if this stream has been aborted.
• Other exceptions that occurred due to an error while retrieving the elements.

Specified by:

drainAll in interface StreamMessage<T>

Returns:

the CompletableFuture which will be completed with the list of the elements retrieved.

drainAll

public final CompletableFuture<List<T>> drainAll(boolean withPooledObjects)

Description copied from interface: StreamMessage

Subscribes to this StreamMessage and retrieves all elements from it. The returned CompletableFuture may be completed exceptionally with the following exceptions:

• IllegalStateException if other Subscriber subscribed to this stream already.
• AbortedStreamException if this stream has been aborted.
• Other exceptions that occurred due to an error while retrieving the elements.

Specified by:

drainAll in interface StreamMessage<T>

Returns:

the CompletableFuture which will be completed with the list of the elements retrieved.

drainAll

public final CompletableFuture<List<T>> drainAll(SubscriptionOption... options)

Description copied from interface: StreamMessage

Subscribes to this StreamMessage and retrieves all elements from it. The returned CompletableFuture may be completed exceptionally with the following exceptions:

• IllegalStateException if other Subscriber subscribed to this stream already.
• AbortedStreamException if this stream has been aborted.
• Other exceptions that occurred due to an error while retrieving the elements.

Specified by:

drainAll in interface StreamMessage<T>

Parameters:

options - SubscriptionOptions to subscribe with. Note that SubscriptionOption.NOTIFY_CANCELLATION is ineffective because there's no cancelling while draining all elements.

Returns:

the CompletableFuture which will be completed with the list of the elements retrieved.

drainAll

public final CompletableFuture<List<T>> drainAll(EventExecutor executor,
                                                 boolean withPooledObjects)

Description copied from interface: StreamMessage

Subscribes to this StreamMessage and retrieves all elements from it. The returned CompletableFuture may be completed exceptionally with the following exceptions:

• IllegalStateException if other Subscriber subscribed to this stream already.
• AbortedStreamException if this stream has been aborted.
• Other exceptions that occurred due to an error while retrieving the elements.

Specified by:

drainAll in interface StreamMessage<T>

Parameters:

executor - the executor to retrieve all elements

Returns:

the CompletableFuture which will be completed with the list of the elements retrieved.

drainAll

public final CompletableFuture<List<T>> drainAll(EventExecutor executor)

Description copied from interface: StreamMessage

Subscribes to this StreamMessage and retrieves all elements from it. The returned CompletableFuture may be completed exceptionally with the following exceptions:

• IllegalStateException if other Subscriber subscribed to this stream already.
• AbortedStreamException if this stream has been aborted.
• Other exceptions that occurred due to an error while retrieving the elements.

Specified by:

drainAll in interface StreamMessage<T>

Parameters:

executor - the executor to retrieve all elements

Returns:

the CompletableFuture which will be completed with the list of the elements retrieved.

drainAll

public final CompletableFuture<List<T>> drainAll(EventExecutor executor,
                                                 SubscriptionOption... options)

Description copied from interface: StreamMessage

Subscribes to this StreamMessage and retrieves all elements from it. The returned CompletableFuture may be completed exceptionally with the following exceptions:

• IllegalStateException if other Subscriber subscribed to this stream already.
• AbortedStreamException if this stream has been aborted.
• Other exceptions that occurred due to an error while retrieving the elements.

Specified by:

drainAll in interface StreamMessage<T>

Parameters:

executor - the executor to retrieve all elements

options - SubscriptionOptions to subscribe with. Note that SubscriptionOption.NOTIFY_CANCELLATION is ineffective because there's no cancelling while draining all elements.

Returns:

the CompletableFuture which will be completed with the list of the elements retrieved.

completionFuture

public final CompletableFuture<Void> completionFuture()

Description copied from interface: StreamMessage

Returns a CompletableFuture that completes when this stream is complete, either successfully or exceptionally, including cancellation and abortion.

A StreamMessage is complete (or 'fully consumed') when:

• the Subscriber consumes all elements and Subscriber.onComplete() is invoked,
• an error occurred and Subscriber.onError(Throwable) is invoked,
• the Subscription has been cancelled or
• StreamMessage.abort() has been requested.

Specified by:

completionFuture in interface StreamMessage<T>

onRemoval

protected void onRemoval(T obj)

Invoked after an element is removed from the StreamMessage and before Subscriber.onNext(Object) is invoked.

Parameters:

obj - the removed element