Package rx

Class Subscriber<T>

java.lang.Object
rx.Subscriber<T>
Type Parameters:
T - the type of items the Subscriber expects to observe
All Implemented Interfaces:
Observer<T>, Subscription
Direct Known Subclasses:
ActionSubscriber, BlockingOperatorLatest.LatestObserverIterator, BlockingOperatorMostRecent.MostRecentObserver, BlockingOperatorNext.NextObserver, BlockingOperatorToIterator.SubscriberIterator, CompletableOnSubscribeConcat.CompletableConcatSubscriber, CompletableOnSubscribeMerge.CompletableMergeSubscriber, DeferredScalarSubscriber, ObserverSubscriber, OnSubscribeAmb.AmbSubscriber, OnSubscribeCombineLatest.CombinerSubscriber, OnSubscribeConcatMap.ConcatMapInnerSubscriber, OnSubscribeConcatMap.ConcatMapSubscriber, OnSubscribeDetach.DetachSubscriber, OnSubscribeFilter.FilterSubscriber, OnSubscribeFlattenIterable.FlattenIterableSubscriber, OnSubscribeGroupJoin.ResultManager.LeftDurationObserver, OnSubscribeGroupJoin.ResultManager.LeftObserver, OnSubscribeGroupJoin.ResultManager.RightDurationObserver, OnSubscribeGroupJoin.ResultManager.RightObserver, OnSubscribeGroupJoin.WindowObservableFunc.WindowSubscriber, OnSubscribeJoin.ResultSink.LeftSubscriber, OnSubscribeJoin.ResultSink.LeftSubscriber.LeftDurationSubscriber, OnSubscribeJoin.ResultSink.RightSubscriber, OnSubscribeJoin.ResultSink.RightSubscriber.RightDurationSubscriber, OnSubscribeMap.MapSubscriber, OnSubscribeOnAssembly.OnAssemblySubscriber, OnSubscribePublishMulticast.ParentSubscriber, OnSubscribeReduce.ReduceSubscriber, OperatorBufferWithSingleObservable.BufferingSubscriber, OperatorBufferWithSize.BufferExact, OperatorBufferWithSize.BufferOverlap, OperatorBufferWithSize.BufferSkip, OperatorBufferWithStartEndObservable.BufferingSubscriber, OperatorBufferWithTime.ExactSubscriber, OperatorBufferWithTime.InexactSubscriber, OperatorCast.CastSubscriber, OperatorDoOnRequest.ParentSubscriber, OperatorEagerConcatMap.EagerInnerSubscriber, OperatorEagerConcatMap.EagerOuterSubscriber, OperatorGroupBy.GroupBySubscriber, OperatorMapNotification.MapNotificationSubscriber, OperatorMapPair.MapPairSubscriber, OperatorMaterialize.ParentSubscriber, OperatorMerge.InnerSubscriber, OperatorMerge.MergeSubscriber, OperatorObserveOn.ObserveOnSubscriber, OperatorOnBackpressureBuffer.BufferSubscriber, OperatorOnBackpressureLatest.LatestSubscriber, OperatorPublish.PublishSubscriber, OperatorReplay.ReplaySubscriber, OperatorRetryWithPredicate.SourceSubscriber, OperatorSampleWithTime.SamplerSubscriber, OperatorSingle.ParentSubscriber, OperatorSwitch.InnerSubscriber, OperatorSwitch.SwitchSubscriber, OperatorSwitchIfEmpty.AlternateSubscriber, OperatorSwitchIfEmpty.ParentSubscriber, OperatorTakeLast.TakeLastSubscriber, OperatorTakeLastTimed.TakeLastTimedSubscriber, OperatorTakeTimed.TakeSubscriber, OperatorTakeUntilPredicate.ParentSubscriber, OperatorTimeoutBase.TimeoutSubscriber, OperatorWindowWithObservable.BoundarySubscriber, OperatorWindowWithObservable.SourceSubscriber, OperatorWindowWithObservableFactory.BoundarySubscriber, OperatorWindowWithObservableFactory.SourceSubscriber, OperatorWindowWithSize.WindowExact, OperatorWindowWithSize.WindowOverlap, OperatorWindowWithSize.WindowSkip, OperatorWindowWithStartEndObservable.SourceSubscriber, OperatorWindowWithTime.ExactSubscriber, OperatorWindowWithTime.InexactSubscriber, OperatorWithLatestFromMany.WithLatestMainSubscriber, OperatorWithLatestFromMany.WithLatestOtherSubscriber, OperatorZip.Zip.InnerSubscriber, OperatorZip.ZipSubscriber, SafeSubscriber, SerializedSubscriber, TestSubscriber
public abstract class Subscriber<T> extends Object implements Observer<T>, Subscription
Provides a mechanism for receiving push-based notifications from Observables, and permits manual unsubscribing from these Observables.

After a Subscriber calls an Observable's subscribe method, the Observable calls the Subscriber's Observer.onNext(T) method to emit items. A well-behaved Observable will call a Subscriber's Observer.onCompleted() method exactly once or the Subscriber's Observer.onError(java.lang.Throwable) method exactly once.

See Also:

  • Field Summary

    Fields
    Modifier and Type
    Field
    Description
    private static final long
    NOT_SET
     
    private Producer
    producer
     
    private long
    requested
     
    private final Subscriber<?>
    subscriber
     
    private final SubscriptionList
    subscriptions
     

  • Constructor Summary

    Constructors
    Modifier
    Constructor
    Description
    protected
    Subscriber()
     
    protected
    Subscriber(Subscriber<?> subscriber)
    Construct a Subscriber by using another Subscriber for backpressure and for holding the subscription list (when this.add(sub) is called this will in fact call subscriber.add(sub)).
    protected
    Subscriber(Subscriber<?> subscriber, boolean shareSubscriptions)
    Construct a Subscriber by using another Subscriber for backpressure and optionally for holding the subscription list (if shareSubscriptions is true then when this.add(sub) is called this will in fact call subscriber.add(sub)).

  • Method Summary

    Modifier and Type
    Method
    Description
    final void
    add(Subscription s)
    Adds a Subscription to this Subscriber's list of subscriptions if this list is not marked as unsubscribed.
    private void
    addToRequested(long n)
     
    final boolean
    isUnsubscribed()
    Indicates whether this Subscriber has unsubscribed from its list of subscriptions.
    void
    onStart()
    This method is invoked when the Subscriber and Observable have been connected but the Observable has not yet begun to emit items or send notifications to the Subscriber.
    protected final void
    request(long n)
    Request a certain maximum number of emitted items from the Observable this Subscriber is subscribed to.
    void
    setProducer(Producer p)
    If other subscriber is set (by calling constructor Subscriber(Subscriber) or Subscriber(Subscriber, boolean)) then this method calls setProducer on the other subscriber.
    final void
    unsubscribe()
    Stops the receipt of notifications on the Subscriber that was registered when this Subscription was received.

    Methods inherited from class java.lang.Object

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

    Methods inherited from interface rx.Observer

    onCompleted, onError, onNext

  • Field Details

  • Constructor Details

    • Subscriber

      protected Subscriber()

    • Subscriber

      protected Subscriber(Subscriber<?> subscriber)
      Construct a Subscriber by using another Subscriber for backpressure and for holding the subscription list (when this.add(sub) is called this will in fact call subscriber.add(sub)).
      Parameters:
      subscriber - the other Subscriber

    • Subscriber

      protected Subscriber(Subscriber<?> subscriber, boolean shareSubscriptions)
      Construct a Subscriber by using another Subscriber for backpressure and optionally for holding the subscription list (if shareSubscriptions is true then when this.add(sub) is called this will in fact call subscriber.add(sub)).

      To retain the chaining of subscribers when setting shareSubscriptions to false, add the created instance to subscriber via add(rx.Subscription).

      Parameters:
      subscriber - the other Subscriber
      shareSubscriptions - true to share the subscription list in subscriber with this instance
      Since:
      1.0.6

  • Method Details

    • add

      public final void add(Subscription s)
      Adds a Subscription to this Subscriber's list of subscriptions if this list is not marked as unsubscribed. If the list is marked as unsubscribed, add will indicate this by explicitly unsubscribing the new Subscription as well.
      Parameters:
      s - the Subscription to add

    • unsubscribe

      public final void unsubscribe()
      Description copied from interface: Subscription
      Stops the receipt of notifications on the Subscriber that was registered when this Subscription was received.

      This allows unregistering an Subscriber before it has finished receiving all events (i.e. before onCompleted is called).

      Specified by:
      unsubscribe in interface Subscription

    • isUnsubscribed

      public final boolean isUnsubscribed()
      Indicates whether this Subscriber has unsubscribed from its list of subscriptions.
      Specified by:
      isUnsubscribed in interface Subscription
      Returns:
      true if this Subscriber has unsubscribed from its subscriptions, false otherwise

    • onStart

      public void onStart()
      This method is invoked when the Subscriber and Observable have been connected but the Observable has not yet begun to emit items or send notifications to the Subscriber. Override this method to add any useful initialization to your subscription, for instance to initiate backpressure.

    • request

      protected final void request(long n)
      Request a certain maximum number of emitted items from the Observable this Subscriber is subscribed to. This is a way of requesting backpressure. To disable backpressure, pass Long.MAX_VALUE to this method.

      Requests are additive but if a sequence of requests totals more than Long.MAX_VALUE then Long.MAX_VALUE requests will be actioned and the extras may be ignored. Arriving at Long.MAX_VALUE by addition of requests cannot be assumed to disable backpressure. For example, the code below may result in Long.MAX_VALUE requests being actioned only. 

       request(100);
 request(Long.MAX_VALUE-1);
      Parameters:
      n - the maximum number of items you want the Observable to emit to the Subscriber at this time, or Long.MAX_VALUE if you want the Observable to emit items at its own pace
      Throws:
      IllegalArgumentException - if n is negative

    • addToRequested

      private void addToRequested(long n)

    • setProducer

      public void setProducer(Producer p)
      If other subscriber is set (by calling constructor Subscriber(Subscriber) or Subscriber(Subscriber, boolean)) then this method calls setProducer on the other subscriber. If the other subscriber is not set and no requests have been made to this subscriber then p.request(Long.MAX_VALUE) is called. If the other subscriber is not set and some requests have been made to this subscriber then p.request(n) is called where n is the accumulated requests to this subscriber.
      Parameters:
      p - producer to be used by this subscriber or the other subscriber (or recursively its other subscriber) to make requests from