Package io.smallrye.mutiny.groups

Class UniSubscribe<T>

  • Type Parameters:
    T - the type of item
    public class UniSubscribe<T>
extends java.lang.Object
    Allow subscribing to a Uni to be notified of the different events coming from upstream. Two kind of events can be received:
    • item - the item of the Uni, can be null
    • failure - the failure propagated by the Uni

    • Constructor Detail

      • UniSubscribe

        public UniSubscribe​(AbstractUni<T> upstream)

    • Method Detail

      • withSubscriber

        public <S extends UniSubscriber<? super T>> S withSubscriber​(S subscriber)
        Requests the Uni to start computing the item.

        This is a "factory method" and can be called multiple times, each time starting a new UniSubscription. Each UniSubscription will work for only a single UniSubscriber. A UniSubscriber should only subscribe once to a single Uni.

        If the Uni rejects the subscription attempt or otherwise fails it will fire a failure event receiving by UniSubscriber.onFailure(Throwable).

        Type Parameters:
        S - the type of subscriber returned
        Parameters:
        subscriber - the subscriber, must not be null
        Returns:
        the passed subscriber

      • withSerializedSubscriber

        public <S extends UniSubscriber<? super T>> S withSerializedSubscriber​(S subscriber)
        Requests the Uni to start computing the item, but wraps the provided subscriber in a UniSerializedSubscriber instance that enforces correct events ordering.

        This is a "factory method" and can be called multiple times, each time starting a new UniSubscription. Each UniSubscription will work for only a single UniSubscriber. A UniSubscriber should only subscribe once to a single Uni.

        If the Uni rejects the subscription attempt or otherwise fails it will fire a failure event receiving by UniSubscriber.onFailure(Throwable).

        Type Parameters:
        S - the type of subscriber returned
        Parameters:
        subscriber - the subscriber, must not be null
        Returns:
        the passed subscriber

      • with

        public Cancellable with​(java.util.function.Consumer<? super T> onItemCallback,
                        java.util.function.Consumer<? super java.lang.Throwable> onFailureCallback)
        Like withSubscriber(UniSubscriber) with creating an artificial UniSubscriber calling the onItem and onFailure callbacks when the events are received.

        Unlike withSubscriber(UniSubscriber), this method returns the subscription that can be used to cancel the subscription.

        Parameters:
        onItemCallback - callback invoked when the an item event is received, potentially called with null is received. The callback must not be null
        onFailureCallback - callback invoked when a failure event is received, must not be null
        Returns:
        an object to cancel the computation

      • with

        public Cancellable with​(java.util.function.Consumer<? super T> onItemCallback)
        Like withSubscriber(UniSubscriber) with creating an artificial UniSubscriber calling the onItem when the item is received.

        Unlike withSubscriber(UniSubscriber), this method returns the subscription that can be used to cancel the subscription.

        Unlike with(Consumer, Consumer), this method does not handle failure, and the failure event is dropped.

        Parameters:
        onItemCallback - callback invoked when the an item event is received, potentially called with null is received. The callback must not be null
        Returns:
        an object to cancel the computation

      • asCompletionStage

        public java.util.concurrent.CompletableFuture<T> asCompletionStage()
        Like withSubscriber(UniSubscriber) but provides a CompletableFuture to retrieve the completed item (potentially null) and allow chaining operations.
        Returns:
        a CompletableFuture to retrieve the item and chain operations on the resolved item or failure. The returned CompletableFuture can also be used to cancel the computation.