Module io.smallrye.mutiny

Package io.smallrye.mutiny.subscription

Class UniSerializedSubscriber<T>

java.lang.Object

io.smallrye.mutiny.subscription.UniSerializedSubscriber<T>

All Implemented Interfaces:

Cancellable, ContextSupport, UniSubscriber<T>, UniSubscription, java.util.concurrent.Flow.Subscription

public class UniSerializedSubscriber<T>
extends java.lang.Object
implements UniSubscriber<T>, UniSubscription

An implementation of UniSubscriber and UniSubscription making sure event handlers are only called once.

Constructor Summary

Constructors

Constructor	Description
UniSerializedSubscriber(AbstractUni<T> upstream, UniSubscriber<? super T> subscriber)

Method Summary

Modifier and Type	Method	Description
void	cancel()	Requests the Uni to cancel and clean up resources.
Context	context()	Provide a context.
void	onFailure(java.lang.Throwable throwable)	Called if the computation of the item by the subscriber Uni failed.
void	onItem(T item)	Event handler called once the item has been computed by the subscribed Uni.
void	onSubscribe(UniSubscription subscription)	Event handler called once the subscribed Uni has taken into account the subscription.
static <T> void	subscribe(AbstractUni<T> source, UniSubscriber<? super T> subscriber)

Methods inherited from class java.lang.Object

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

Methods inherited from interface io.smallrye.mutiny.subscription.UniSubscription

request

Constructor Detail

UniSerializedSubscriber

public UniSerializedSubscriber(AbstractUni<T> upstream,
                               UniSubscriber<? super T> subscriber)

Method Detail

subscribe

public static <T> void subscribe(AbstractUni<T> source,
                                 UniSubscriber<? super T> subscriber)

context

public Context context()

Description copied from interface: ContextSupport

Provide a context.

Since calls to this method shall only be triggered when a Mutiny pipeline uses a withContext operator, there is no need in general for caching the context value in a field of the implementing class. Exceptions include operators that have cross-subscriber semantics such as memoizers or broadcasters.

This method is expected to be called once per withContext operator.

Specified by:

context in interface ContextSupport

Returns:

the context, must not be null.

onSubscribe

public void onSubscribe(UniSubscription subscription)

Description copied from interface: UniSubscriber

Event handler called once the subscribed Uni has taken into account the subscription. The Uni have triggered the computation of the item.

IMPORTANT: UniSubscriber.onItem(Object) and UniSubscriber.onFailure(Throwable) would not be called before the invocation of this method.

• Executor: Operate on no particular executor, except if Uni.runSubscriptionOn(Executor) has been called
• Exception: Throwing an exception cancels the subscription, UniSubscriber.onItem(Object) and UniSubscriber.onFailure(Throwable) won't be called

Specified by:

onSubscribe in interface UniSubscriber<T>

Parameters:

subscription - the subscription allowing to cancel the computation.

onItem

public void onItem(T item)

Description copied from interface: UniSubscriber

Event handler called once the item has been computed by the subscribed Uni.

IMPORTANT: this method will be only called once per subscription. If UniSubscriber.onFailure(Throwable) is called, this method won't be called.

• Executor: Operate on no particular executor, except if Uni.emitOn(java.util.concurrent.Executor) has been called
• Exception: Throwing an exception cancels the subscription.

Specified by:

onItem in interface UniSubscriber<T>

Parameters:

item - the item, may be null.

onFailure

public void onFailure(java.lang.Throwable throwable)

Description copied from interface: UniSubscriber

Called if the computation of the item by the subscriber Uni failed.

IMPORTANT: this method will be only called once per subscription. If UniSubscriber.onItem(Object) is called, this method won't be called.

• Executor: Operate on no particular executor, except if Uni.emitOn(java.util.concurrent.Executor) has been called
• Exception: Throwing an exception cancels the subscription.

Specified by:

onFailure in interface UniSubscriber<T>

Parameters:

throwable - the failure, cannot be null.

cancel

public void cancel()

Description copied from interface: UniSubscription

Requests the Uni to cancel and clean up resources. If the item is retrieved after cancellation, it is not forwarded to the subscriber. If the cancellation happens after the delivery of the item, this call is ignored.

Calling this method, emits the cancellation event upstream.

Specified by:

cancel in interface Cancellable

Specified by:

cancel in interface java.util.concurrent.Flow.Subscription

Specified by:

cancel in interface UniSubscription