reactor.core.publisher

Class UnicastProcessor<T>

java.lang.Object

reactor.core.publisher.Flux<OUT>

reactor.core.publisher.FluxProcessor<T,T>

reactor.core.publisher.UnicastProcessor<T>

Type Parameters:

T - the input and output type

All Implemented Interfaces:

Iterable<T>, Collection<T>, Queue<T>, Processor<T,T>, Publisher<T>, Subscriber<T>, Subscription, CorePublisher<T>, CoreSubscriber<T>, Disposable, Fuseable, Fuseable.QueueSubscription<T>, Scannable

Deprecated.

to be removed in 3.5, prefer clear cut usage of Sinks through variations under Sinks.many().unicast().

@Deprecated
public final class UnicastProcessor<T>
extends FluxProcessor<T,T>
implements Fuseable.QueueSubscription<T>, Fuseable

A Processor implementation that takes a custom queue and allows only a single subscriber. UnicastProcessor allows multiplexing of the events which means that it supports multiple producers and only one consumer. However, it should be noticed that multi-producer case is only valid if appropriate Queue is provided. Otherwise, it could break Reactive Streams Spec if Publishers publish on different threads.

Note: UnicastProcessor does not respect the actual subscriber's demand as it is described in Reactive Streams Spec. However, UnicastProcessor embraces configurable Queue internally which allows enabling backpressure support and preventing of consumer's overwhelming. Hence, interaction model between producers and UnicastProcessor will be PUSH only. In opposite, interaction model between UnicastProcessor and consumer will be PUSH-PULL as defined in Reactive Streams Spec. In the case when upstream's signals overflow the bound of internal Queue, UnicastProcessor will fail with signaling onError( reactor.core.Exceptions.OverflowException).

Note: The implementation keeps the order of signals. That means that in case of terminal signal (completion or error signals) it will be postponed until all of the previous signals has been consumed.

Nested Class Summary

Nested classes/interfaces inherited from interface reactor.core.Fuseable

Fuseable.ConditionalSubscriber<T>, Fuseable.QueueSubscription<T>, Fuseable.ScalarCallable<T>, Fuseable.SynchronousSubscription<T>

Nested classes/interfaces inherited from interface reactor.core.Scannable

Scannable.Attr<T>

Nested classes/interfaces inherited from interface reactor.core.Disposable

Disposable.Composite, Disposable.Swap

Field Summary

Fields inherited from interface reactor.core.Fuseable.QueueSubscription

NOT_SUPPORTED_MESSAGE

Fields inherited from interface reactor.core.Fuseable

ANY, ASYNC, NONE, SYNC, THREAD_BARRIER

Fields inherited from interface reactor.core.Scannable

OPERATOR_NAME_UNRELATED_WORDS_PATTERN

Constructor Summary

Constructors

Constructor and Description
UnicastProcessor(Queue<T> queue) Deprecated.
UnicastProcessor(Queue<T> queue, Consumer<? super T> onOverflow, Disposable onTerminate) Deprecated.
UnicastProcessor(Queue<T> queue, Disposable onTerminate) Deprecated.

Method Summary

Modifier and Type	Method and Description
CoreSubscriber<? super T>	actual() Deprecated.
Flux<T>	asFlux() Deprecated. Return a Flux view of this sink.
void	cancel() Deprecated.
void	clear() Deprecated.
static <E> UnicastProcessor<E>	create() Deprecated. use Sinks.many().unicast().onBackpressureBuffer() (or the unsafe variant if you're sure about external synchronization). To be removed in 3.5.
static <E> UnicastProcessor<E>	create(Queue<E> queue) Deprecated. use Sinks.many().unicast().onBackpressureBuffer(queue) (or the unsafe variant if you're sure about external synchronization). To be removed in 3.5.
static <E> UnicastProcessor<E>	create(Queue<E> queue, Consumer<? super E> onOverflow, Disposable endcallback) Deprecated. use Sinks.many().unicast().onBackpressureBuffer(queue, endCallback) (or the unsafe variant if you're sure about external synchronization). The onOverflow callback is not supported anymore. To be removed in 3.5.
static <E> UnicastProcessor<E>	create(Queue<E> queue, Disposable endcallback) Deprecated. use Sinks.many().unicast().onBackpressureBuffer(queue, endCallback) (or the unsafe variant if you're sure about external synchronization). To be removed in 3.5.
Context	currentContext() Deprecated. Request a Context from dependent components which can include downstream operators during subscribing or a terminal Subscriber.
int	currentSubscriberCount() Deprecated. Get how many Subscribers are currently subscribed to the sink.
long	downstreamCount() Deprecated. Return the number of active Subscriber or -1 if untracked.
default void	emitComplete(Sinks.EmitFailureHandler failureHandler) A simplified attempt at completing via the Sinks.Many.tryEmitComplete() API, generating an onComplete signal.
default void	emitError(Throwable error, Sinks.EmitFailureHandler failureHandler) A simplified attempt at failing the sequence via the Sinks.Many.tryEmitError(Throwable) API, generating an onError signal.
void	emitNext(T value, Sinks.EmitFailureHandler failureHandler) Deprecated. A simplified attempt at emitting a non-null element via the Sinks.Many.tryEmitNext(Object) API, generating an onNext signal.
int	getBufferSize() Deprecated. Return the processor buffer capacity if any or Integer.MAX_VALUE
Throwable	getError() Deprecated. Current error if any, default to null
int	getPrefetch() Deprecated. The prefetch configuration of the Flux
boolean	hasDownstreams() Deprecated. Return true if any Subscriber is actively subscribed
Stream<Scannable>	inners() Deprecated. Return a Stream of referenced inners (flatmap, multicast etc)
boolean	isDisposed() Deprecated. Optionally return true when the resource or task is disposed.
boolean	isEmpty() Deprecated.
protected boolean	isIdentityProcessor() Deprecated. Return true if FluxProcessor<T, T>
boolean	isTerminated() Deprecated. Has this upstream finished or "completed" / "failed" ?
void	onComplete() Deprecated.
void	onError(Throwable throwable) Deprecated.
void	onNext(T t) Deprecated.
void	onSubscribe(Subscription s) Deprecated. Implementors should initialize any state used by Subscriber.onNext(Object) before calling Subscription.request(long).
T	poll() Deprecated.
void	request(long n) Deprecated.
int	requestFusion(int requestedMode) Deprecated. Request a specific fusion mode from this QueueSubscription.
Object	scanUnsafe(Scannable.Attr key) Deprecated. This method is used internally by components to define their key-value mappings in a single place.
int	size() Deprecated.
void	subscribe(CoreSubscriber<? super T> actual) Deprecated. An internal Publisher.subscribe(Subscriber) that will bypass Hooks.onLastOperator(Function) pointcut.
Sinks.EmitResult	tryEmitComplete() Deprecated. Try to terminate the sequence successfully, generating an onComplete signal.
Sinks.EmitResult	tryEmitError(Throwable t) Deprecated. Try to fail the sequence, generating an onError signal.
Sinks.EmitResult	tryEmitNext(T t) Deprecated. Try emitting a non-null element, generating an onNext signal.

Methods inherited from class reactor.core.publisher.FluxProcessor

dispose, hasCompleted, hasError, isSerialized, serialize, serializeAlways, sink, sink, switchOnNext, wrap

Methods inherited from class reactor.core.publisher.Flux

all, any, as, blockFirst, blockFirst, blockLast, blockLast, buffer, buffer, buffer, buffer, buffer, buffer, buffer, buffer, buffer, buffer, buffer, bufferTimeout, bufferTimeout, bufferTimeout, bufferTimeout, bufferTimeout, bufferTimeout, bufferTimeout, bufferTimeout, bufferUntil, bufferUntil, bufferUntilChanged, bufferUntilChanged, bufferUntilChanged, bufferWhen, bufferWhen, bufferWhile, cache, cache, cache, cache, cache, cache, cancelOn, cast, checkpoint, checkpoint, checkpoint, collect, collect, collectList, collectMap, collectMap, collectMap, collectMultimap, collectMultimap, collectMultimap, collectSortedList, collectSortedList, combineLatest, combineLatest, combineLatest, combineLatest, combineLatest, combineLatest, combineLatest, combineLatest, combineLatest, concat, concat, concat, concat, concatDelayError, concatDelayError, concatDelayError, concatDelayError, concatMap, concatMap, concatMapDelayError, concatMapDelayError, concatMapDelayError, concatMapIterable, concatMapIterable, concatWith, concatWithValues, contextCapture, contextWrite, contextWrite, count, create, create, defaultIfEmpty, defer, deferContextual, delayElements, delayElements, delaySequence, delaySequence, delaySubscription, delaySubscription, delaySubscription, delayUntil, dematerialize, distinct, distinct, distinct, distinct, distinctUntilChanged, distinctUntilChanged, distinctUntilChanged, doAfterTerminate, doFinally, doFirst, doOnCancel, doOnComplete, doOnDiscard, doOnEach, doOnError, doOnError, doOnError, doOnNext, doOnRequest, doOnSubscribe, doOnTerminate, elapsed, elapsed, elementAt, elementAt, empty, error, error, error, expand, expand, expandDeep, expandDeep, filter, filterWhen, filterWhen, first, first, firstWithSignal, firstWithSignal, firstWithValue, firstWithValue, flatMap, flatMap, flatMap, flatMap, flatMapDelayError, flatMapIterable, flatMapIterable, flatMapSequential, flatMapSequential, flatMapSequential, flatMapSequentialDelayError, from, fromArray, fromIterable, fromStream, fromStream, generate, generate, generate, groupBy, groupBy, groupBy, groupBy, groupJoin, handle, hasElement, hasElements, hide, ignoreElements, index, index, interval, interval, interval, interval, join, just, just, last, last, limitRate, limitRate, limitRequest, log, log, log, log, log, log, map, mapNotNull, materialize, merge, merge, merge, merge, merge, merge, mergeComparing, mergeComparing, mergeComparing, mergeComparingDelayError, mergeComparingWith, mergeDelayError, mergeOrdered, mergeOrdered, mergeOrdered, mergeOrderedWith, mergePriority, mergePriority, mergePriority, mergePriorityDelayError, mergeSequential, mergeSequential, mergeSequential, mergeSequential, mergeSequential, mergeSequential, mergeSequentialDelayError, mergeSequentialDelayError, mergeSequentialDelayError, mergeWith, metrics, name, never, next, ofType, onAssembly, onAssembly, onBackpressureBuffer, onBackpressureBuffer, onBackpressureBuffer, onBackpressureBuffer, onBackpressureBuffer, onBackpressureBuffer, onBackpressureBuffer, onBackpressureDrop, onBackpressureDrop, onBackpressureError, onBackpressureLatest, onErrorComplete, onErrorComplete, onErrorComplete, onErrorContinue, onErrorContinue, onErrorContinue, onErrorMap, onErrorMap, onErrorMap, onErrorResume, onErrorResume, onErrorResume, onErrorReturn, onErrorReturn, onErrorReturn, onErrorStop, onTerminateDetach, or, parallel, parallel, parallel, publish, publish, publish, publish, publishNext, publishOn, publishOn, publishOn, push, push, range, reduce, reduce, reduceWith, repeat, repeat, repeat, repeat, repeatWhen, replay, replay, replay, replay, replay, replay, retry, retry, retryWhen, sample, sample, sampleFirst, sampleFirst, sampleTimeout, sampleTimeout, scan, scan, scanWith, share, shareNext, single, single, singleOrEmpty, skip, skip, skip, skipLast, skipUntil, skipUntilOther, skipWhile, sort, sort, startWith, startWith, startWith, subscribe, subscribe, subscribe, subscribe, subscribe, subscribe, subscribe, subscribeOn, subscribeOn, subscribeWith, switchIfEmpty, switchMap, switchMap, switchOnFirst, switchOnFirst, switchOnNext, switchOnNext, tag, take, take, take, take, takeLast, takeUntil, takeUntilOther, takeWhile, tap, tap, tap, then, then, thenEmpty, thenMany, timed, timed, timeout, timeout, timeout, timeout, timeout, timeout, timeout, timestamp, timestamp, toIterable, toIterable, toIterable, toStream, toStream, toString, transform, transformDeferred, transformDeferredContextual, using, using, usingWhen, usingWhen, window, window, window, window, window, window, window, windowTimeout, windowTimeout, windowTimeout, windowTimeout, windowUntil, windowUntil, windowUntil, windowUntilChanged, windowUntilChanged, windowUntilChanged, windowWhen, windowWhile, windowWhile, withLatestFrom, zip, zip, zip, zip, zip, zip, zip, zip, zip, zip, zip, zip, zip, zipWith, zipWith, zipWith, zipWith, zipWithIterable, zipWithIterable

Methods inherited from class java.lang.Object

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

Methods inherited from interface reactor.core.Fuseable.QueueSubscription

add, addAll, contains, containsAll, element, iterator, offer, peek, remove, remove, removeAll, retainAll, toArray, toArray

Methods inherited from interface java.util.Collection

equals, hashCode, parallelStream, removeIf, spliterator, stream

Methods inherited from interface java.lang.Iterable

forEach

Methods inherited from interface reactor.core.Fuseable

fusionModeName, fusionModeName

Methods inherited from interface reactor.core.Scannable

actuals, from, isScanAvailable, name, parents, scan, scanOrDefault, stepName, steps, tags, tagsDeduplicated

Methods inherited from interface org.reactivestreams.Publisher

subscribe

Constructor Detail

UnicastProcessor

public UnicastProcessor(Queue<T> queue)

Deprecated.

UnicastProcessor

public UnicastProcessor(Queue<T> queue,
                        Disposable onTerminate)

Deprecated.

UnicastProcessor

@Deprecated
public UnicastProcessor(Queue<T> queue,
                                    Consumer<? super T> onOverflow,
                                    Disposable onTerminate)

Deprecated.

Method Detail

create

@Deprecated
public static <E> UnicastProcessor<E> create()

Deprecated. use Sinks.many().unicast().onBackpressureBuffer() (or the unsafe variant if you're sure about external synchronization). To be removed in 3.5.

Create a new UnicastProcessor that will buffer on an internal queue in an unbounded fashion.

Type Parameters:

E - the relayed type

Returns:

a unicast FluxProcessor

create

@Deprecated
public static <E> UnicastProcessor<E> create(Queue<E> queue)

Deprecated. use Sinks.many().unicast().onBackpressureBuffer(queue) (or the unsafe variant if you're sure about external synchronization). To be removed in 3.5.

Create a new UnicastProcessor that will buffer on a provided queue in an unbounded fashion.

Type Parameters:

E - the relayed type

Parameters:

queue - the buffering queue

Returns:

a unicast FluxProcessor

create

@Deprecated
public static <E> UnicastProcessor<E> create(Queue<E> queue,
                                                         Disposable endcallback)

Deprecated. use Sinks.many().unicast().onBackpressureBuffer(queue, endCallback) (or the unsafe variant if you're sure about external synchronization). To be removed in 3.5.

Create a new UnicastProcessor that will buffer on a provided queue in an unbounded fashion.

Type Parameters:

E - the relayed type

Parameters:

queue - the buffering queue

endcallback - called on any terminal signal

Returns:

a unicast FluxProcessor

create

@Deprecated
public static <E> UnicastProcessor<E> create(Queue<E> queue,
                                                         Consumer<? super E> onOverflow,
                                                         Disposable endcallback)

Deprecated. use Sinks.many().unicast().onBackpressureBuffer(queue, endCallback) (or the unsafe variant if you're sure about external synchronization). The onOverflow callback is not supported anymore. To be removed in 3.5.

Create a new UnicastProcessor that will buffer on a provided queue in an unbounded fashion.

Type Parameters:

E - the relayed type

Parameters:

queue - the buffering queue

endcallback - called on any terminal signal

onOverflow - called when queue.offer return false and unicastProcessor is about to emit onError.

Returns:

a unicast FluxProcessor

getBufferSize

public int getBufferSize()

Deprecated.

Description copied from class: FluxProcessor

Return the processor buffer capacity if any or Integer.MAX_VALUE

Overrides:

getBufferSize in class FluxProcessor<T,T>

Returns:

processor buffer capacity if any or Integer.MAX_VALUE

inners

public Stream<Scannable> inners()

Deprecated.

Description copied from interface: Scannable

Return a Stream of referenced inners (flatmap, multicast etc)

Specified by:

inners in interface Scannable

Overrides:

inners in class FluxProcessor<T,T>

Returns:

a Stream of referenced inners (flatmap, multicast etc)

scanUnsafe

public Object scanUnsafe(Scannable.Attr key)

Deprecated.

Description copied from interface: Scannable

This method is used internally by components to define their key-value mappings in a single place. Although it is ignoring the generic type of the Scannable.Attr key, implementors should take care to return values of the correct type, and return null if no specific value is available.

For public consumption of attributes, prefer using Scannable.scan(Attr), which will return a typed value and fall back to the key's default if the component didn't define any mapping.

Specified by:

scanUnsafe in interface Scannable

Overrides:

scanUnsafe in class FluxProcessor<T,T>

Parameters:

key - a Scannable.Attr to resolve for the component.

Returns:

the value associated to the key for that specific component, or null if none.

onComplete

public void onComplete()

Deprecated.

Specified by:

onComplete in interface Subscriber<T>

tryEmitComplete

public Sinks.EmitResult tryEmitComplete()

Deprecated.

Description copied from interface: Sinks.Many

Try to terminate the sequence successfully, generating an onComplete signal. The result of the attempt is represented as an Sinks.EmitResult, which possibly indicates error cases.

See the list of failure Sinks.EmitResult in #emitComplete(EmitFailureHandler) javadoc for an example of how each of these can be dealt with, to decide if the emit API would be a good enough fit instead.

Returns:

an Sinks.EmitResult, which should be checked to distinguish different possible failures

See Also:

Subscriber.onComplete()

onError

public void onError(Throwable throwable)

Deprecated.

Specified by:

onError in interface Subscriber<T>

tryEmitError

public Sinks.EmitResult tryEmitError(Throwable t)

Deprecated.

Description copied from interface: Sinks.Many

Try to fail the sequence, generating an onError signal. The result of the attempt is represented as an Sinks.EmitResult, which possibly indicates error cases.

See the list of failure Sinks.EmitResult in #emitError(Throwable, EmitFailureHandler) javadoc for an example of how each of these can be dealt with, to decide if the emit API would be a good enough fit instead.

Parameters:

t - the exception to signal, not null

Returns:

an Sinks.EmitResult, which should be checked to distinguish different possible failures

See Also:

Subscriber.onError(Throwable)

onNext

public void onNext(T t)

Deprecated.

Specified by:

onNext in interface Subscriber<T>

emitNext

public void emitNext(T value,
                     Sinks.EmitFailureHandler failureHandler)

Deprecated.

Description copied from interface: Sinks.Many

A simplified attempt at emitting a non-null element via the Sinks.Many.tryEmitNext(Object) API, generating an onNext signal. If the result of the attempt is not a success, implementations SHOULD retry the Sinks.Many.tryEmitNext(Object) call IF the provided Sinks.EmitFailureHandler returns true. Otherwise, failures are dealt with in a predefined way that might depend on the actual sink implementation (see below for the vanilla reactor-core behavior).

Generally, Sinks.Many.tryEmitNext(Object) is preferable since it allows a custom handling of error cases, although this implies checking the returned Sinks.EmitResult and correctly acting on it. This API is intended as a good default for convenience.

When the Sinks.EmitResult is not a success, vanilla reactor-core operators have the following behavior:

• Sinks.EmitResult.FAIL_ZERO_SUBSCRIBER: no particular handling. should ideally discard the value but at that point there's no Subscriber from which to get a contextual discard handler.
• Sinks.EmitResult.FAIL_OVERFLOW: discard the value (Operators.onDiscard(Object, Context)) then call Sinks.Many.emitError(Throwable, Sinks.EmitFailureHandler) with a Exceptions.failWithOverflow(String) exception.
• Sinks.EmitResult.FAIL_CANCELLED: discard the value (Operators.onDiscard(Object, Context)).
• Sinks.EmitResult.FAIL_TERMINATED: drop the value (Operators.onNextDropped(Object, Context)).
• Sinks.EmitResult.FAIL_NON_SERIALIZED: throw an Sinks.EmissionException mentioning RS spec rule 1.3. Note that Sinks.unsafe() never trigger this result. It would be possible for an Sinks.EmitFailureHandler to busy-loop and optimistically wait for the contention to disappear to avoid this case for safe sinks...

Might throw an unchecked exception as a last resort (eg. in case of a fatal error downstream which cannot be propagated to any asynchronous handler, a bubbling exception, a Sinks.EmitResult.FAIL_NON_SERIALIZED as described above, ...).

Parameters:

value - the value to emit, not null

failureHandler - the failure handler that allows retrying failed Sinks.EmitResult.

See Also:

Sinks.Many.tryEmitNext(Object), Subscriber.onNext(Object)

tryEmitNext

public Sinks.EmitResult tryEmitNext(T t)

Deprecated.

Description copied from interface: Sinks.Many

Try emitting a non-null element, generating an onNext signal. The result of the attempt is represented as an Sinks.EmitResult, which possibly indicates error cases.

See the list of failure Sinks.EmitResult in #emitNext(Object, EmitFailureHandler) javadoc for an example of how each of these can be dealt with, to decide if the emit API would be a good enough fit instead.

Might throw an unchecked exception as a last resort (eg. in case of a fatal error downstream which cannot be propagated to any asynchronous handler, a bubbling exception, ...).

Parameters:

t - the value to emit, not null

Returns:

an Sinks.EmitResult, which should be checked to distinguish different possible failures

See Also:

Subscriber.onNext(Object)

currentSubscriberCount

public int currentSubscriberCount()

Deprecated.

Description copied from interface: Sinks.Many

Get how many Subscribers are currently subscribed to the sink.

This is a best effort peek at the sink state, and a subsequent attempt at emitting to the sink might still return Sinks.EmitResult.FAIL_ZERO_SUBSCRIBER where relevant. (generally in Sinks.Many.tryEmitNext(Object)). Request (and lack thereof) isn't taken into account, all registered subscribers are counted.

Returns:

the number of subscribers at the time of invocation

asFlux

public Flux<T> asFlux()

Deprecated.

Description copied from interface: Sinks.Many

Return a Flux view of this sink. Every call returns the same instance.

Returns:

the Flux view associated to this Sinks.Many

isIdentityProcessor

protected boolean isIdentityProcessor()

Deprecated.

Description copied from class: FluxProcessor

Return true if FluxProcessor<T, T>

Overrides:

isIdentityProcessor in class FluxProcessor<T,T>

Returns:

true if FluxProcessor<T, T>

onSubscribe

public void onSubscribe(Subscription s)

Deprecated.

Description copied from interface: CoreSubscriber

Implementors should initialize any state used by Subscriber.onNext(Object) before calling Subscription.request(long). Should further onNext related state modification occur, thread-safety will be required.

Note that an invalid request <= 0 will not produce an onError and will simply be ignored or reported through a debug-enabled Logger.

Specified by:

onSubscribe in interface Subscriber<T>

Specified by:

onSubscribe in interface CoreSubscriber<T>

getPrefetch

public int getPrefetch()

Deprecated.

Description copied from class: Flux

The prefetch configuration of the Flux

Overrides:

getPrefetch in class Flux<T>

Returns:

the prefetch configuration of the Flux, -1 if unspecified

currentContext

public Context currentContext()

Deprecated.

Description copied from interface: CoreSubscriber

Request a Context from dependent components which can include downstream operators during subscribing or a terminal Subscriber.

Specified by:

currentContext in interface CoreSubscriber<T>

Overrides:

currentContext in class FluxProcessor<T,T>

Returns:

a resolved context or Context.empty()

subscribe

public void subscribe(CoreSubscriber<? super T> actual)

Deprecated.

Description copied from class: Flux

An internal Publisher.subscribe(Subscriber) that will bypass Hooks.onLastOperator(Function) pointcut.

In addition to behave as expected by Publisher.subscribe(Subscriber) in a controlled manner, it supports direct subscribe-time Context passing.

Specified by:

subscribe in interface CorePublisher<T>

Specified by:

subscribe in class Flux<T>

Parameters:

actual - the Subscriber interested into the published sequence

See Also:

Flux.subscribe(Subscriber)

request

public void request(long n)

Deprecated.

Specified by:

request in interface Subscription

cancel

public void cancel()

Deprecated.

Specified by:

cancel in interface Subscription

poll

@Nullable
public T poll()

Deprecated.

Specified by:

poll in interface Queue<T>

size

public int size()

Deprecated.

Specified by:

size in interface Collection<T>

isEmpty

public boolean isEmpty()

Deprecated.

Specified by:

isEmpty in interface Collection<T>

clear

public void clear()

Deprecated.

Specified by:

clear in interface Collection<T>

requestFusion

public int requestFusion(int requestedMode)

Deprecated.

Description copied from interface: Fuseable.QueueSubscription

Request a specific fusion mode from this QueueSubscription.

One should request either SYNC, ASYNC or ANY modes (never NONE) and the implementor should return NONE, SYNC or ASYNC (never ANY).

For example, if a source supports only ASYNC fusion but the intermediate operator supports only SYNC fuseable sources, the operator may request SYNC fusion and the source can reject it via NONE, thus the operator can return NONE as well to downstream and the fusion doesn't happen.

Specified by:

requestFusion in interface Fuseable.QueueSubscription<T>

Parameters:

requestedMode - the mode requested by the intermediate operator

Returns:

the actual fusion mode activated

isDisposed

public boolean isDisposed()

Deprecated.

Description copied from interface: Disposable

Optionally return true when the resource or task is disposed.

Implementations are not required to track disposition and as such may never return true even when disposed. However, they MUST only return true when there's a guarantee the resource or task is disposed.

Specified by:

isDisposed in interface Disposable

Returns:

true when there's a guarantee the resource or task is disposed.

isTerminated

public boolean isTerminated()

Deprecated.

Description copied from class: FluxProcessor

Has this upstream finished or "completed" / "failed" ?

Overrides:

isTerminated in class FluxProcessor<T,T>

Returns:

has this upstream finished or "completed" / "failed" ?

getError

@Nullable
public Throwable getError()

Deprecated.

Description copied from class: FluxProcessor

Current error if any, default to null

Overrides:

getError in class FluxProcessor<T,T>

Returns:

Current error if any, default to null

actual

public CoreSubscriber<? super T> actual()

Deprecated.

downstreamCount

public long downstreamCount()

Deprecated.

Description copied from class: FluxProcessor

Return the number of active Subscriber or -1 if untracked.

Overrides:

downstreamCount in class FluxProcessor<T,T>

Returns:

the number of active Subscriber or -1 if untracked

hasDownstreams

public boolean hasDownstreams()

Deprecated.

Description copied from class: FluxProcessor

Return true if any Subscriber is actively subscribed

Overrides:

hasDownstreams in class FluxProcessor<T,T>

Returns:

true if any Subscriber is actively subscribed

emitComplete

public void emitComplete(Sinks.EmitFailureHandler failureHandler)

Description copied from interface: Sinks.Many

A simplified attempt at completing via the Sinks.Many.tryEmitComplete() API, generating an onComplete signal. If the result of the attempt is not a success, implementations SHOULD retry the Sinks.Many.tryEmitComplete() call IF the provided Sinks.EmitFailureHandler returns true. Otherwise, failures are dealt with in a predefined way that might depend on the actual sink implementation (see below for the vanilla reactor-core behavior).

Generally, Sinks.Many.tryEmitComplete() is preferable since it allows a custom handling of error cases, although this implies checking the returned Sinks.EmitResult and correctly acting on it. This API is intended as a good default for convenience.

When the Sinks.EmitResult is not a success, vanilla reactor-core operators have the following behavior:

• Sinks.EmitResult.FAIL_OVERFLOW: irrelevant as onComplete is not driven by backpressure.
• Sinks.EmitResult.FAIL_ZERO_SUBSCRIBER: the completion can be ignored since nobody is listening. Note that most vanilla reactor sinks never trigger this result for onComplete, replaying the terminal signal to later subscribers instead (to the exception of Sinks.UnicastSpec.onBackpressureError()).
• Sinks.EmitResult.FAIL_CANCELLED: the completion can be ignored since nobody is interested.
• Sinks.EmitResult.FAIL_TERMINATED: the extra completion is basically ignored since there was a previous termination signal, but there is nothing interesting to log.
• Sinks.EmitResult.FAIL_NON_SERIALIZED: throw an Sinks.EmissionException mentioning RS spec rule 1.3. Note that Sinks.unsafe() never trigger this result. It would be possible for an Sinks.EmitFailureHandler to busy-loop and optimistically wait for the contention to disappear to avoid this case in safe sinks...

Might throw an unchecked exception as a last resort (eg. in case of a fatal error downstream which cannot be propagated to any asynchronous handler, a bubbling exception, a Sinks.EmitResult.FAIL_NON_SERIALIZED as described above, ...).

Specified by:

emitComplete in interface Sinks.Many<T>

Parameters:

failureHandler - the failure handler that allows retrying failed Sinks.EmitResult.

See Also:

Sinks.Many.tryEmitComplete(), Subscriber.onComplete()

emitError

public void emitError(Throwable error,
                      Sinks.EmitFailureHandler failureHandler)

Description copied from interface: Sinks.Many

A simplified attempt at failing the sequence via the Sinks.Many.tryEmitError(Throwable) API, generating an onError signal. If the result of the attempt is not a success, implementations SHOULD retry the Sinks.Many.tryEmitError(Throwable) call IF the provided Sinks.EmitFailureHandler returns true. Otherwise, failures are dealt with in a predefined way that might depend on the actual sink implementation (see below for the vanilla reactor-core behavior).

Generally, Sinks.Many.tryEmitError(Throwable) is preferable since it allows a custom handling of error cases, although this implies checking the returned Sinks.EmitResult and correctly acting on it. This API is intended as a good default for convenience.

When the Sinks.EmitResult is not a success, vanilla reactor-core operators have the following behavior:

• Sinks.EmitResult.FAIL_OVERFLOW: irrelevant as onError is not driven by backpressure.
• Sinks.EmitResult.FAIL_ZERO_SUBSCRIBER: the error is ignored since nobody is listening. Note that most vanilla reactor sinks never trigger this result for onError, replaying the terminal signal to later subscribers instead (to the exception of Sinks.UnicastSpec.onBackpressureError()).
• Sinks.EmitResult.FAIL_CANCELLED: the error can be ignored since nobody is interested.
• Sinks.EmitResult.FAIL_TERMINATED: the error unexpectedly follows another terminal signal, so it is dropped via Operators.onErrorDropped(Throwable, Context).
• Sinks.EmitResult.FAIL_NON_SERIALIZED: throw an Sinks.EmissionException mentioning RS spec rule 1.3. Note that Sinks.unsafe() never trigger this result. It would be possible for an Sinks.EmitFailureHandler to busy-loop and optimistically wait for the contention to disappear to avoid this case in safe sinks...

Might throw an unchecked exception as a last resort (eg. in case of a fatal error downstream which cannot be propagated to any asynchronous handler, a bubbling exception, a Sinks.EmitResult.FAIL_NON_SERIALIZED as described above, ...).

Specified by:

emitError in interface Sinks.Many<T>

Parameters:

error - the exception to signal, not null

failureHandler - the failure handler that allows retrying failed Sinks.EmitResult.

See Also:

Sinks.Many.tryEmitError(Throwable), Subscriber.onError(Throwable)