Uses of Interface
rx.Observer

Packages that use Observer

Package	Description
rx	Base reactive classes: Observable, Single and Completable; base reactive consumers; other common base interfaces.
rx.exceptions	Exception handling utilities, safe subscriber exception classes, lifecycle exception classes.
rx.internal.operators	Operators that allow composing Observables to transform and manipulate data in an asynchronous, functional and thread-safe manner.
rx.internal.producers
rx.internal.schedulers
rx.internal.util
rx.observables	Classes extending the Observable base reactive class, synchronous and asynchronous event generators.
rx.observers	Default wrappers and implementations for the base reactive consumer classes and interfaces; utility classes for creating them from callbacks.
rx.subjects	Classes extending the Observable base reactive class and implementing the Observer interface at the same time (aka hot Observables).

Uses of Observer in rx

Subinterfaces of Observer in rx

Modifier and Type	Interface	Description
interface	AsyncEmitter<T>	Abstraction over a RxJava Subscriber that allows associating a resource with it and exposes the current number of downstream requested amount.

Classes in rx that implement Observer

Modifier and Type	Class	Description
class	Subscriber<T>	Provides a mechanism for receiving push-based notifications from Observables, and permits manual unsubscribing from these Observables.

Methods in rx with parameters of type Observer

Modifier and Type	Method	Description
void	Notification.accept(Observer<? super T> observer)	Forwards this notification on to a specified Observer.
final Observable<T>	Observable.doOnEach(Observer<? super T> observer)	Modifies the source Observable so that it notifies an Observer for each item and terminal event it emits.
final Subscription	Observable.subscribe(Observer<? super T> observer)	Subscribes to an Observable and provides an Observer that implements functions to handle the items the Observable emits and any error or completion notification it issues.
final Subscription	Single.subscribe(Observer<? super T> observer)	Subscribes an Observer to this single and returns a Subscription that allows unsubscription.

Uses of Observer in rx.exceptions

Methods in rx.exceptions with parameters of type Observer

Modifier and Type	Method	Description
static void	Exceptions.throwOrReport(Throwable t, Observer<?> o)	Forwards a fatal exception or reports it to the given Observer.
static void	Exceptions.throwOrReport(Throwable t, Observer<?> o, Object value)	Forwards a fatal exception or reports it along with the value caused it to the given Observer.

Uses of Observer in rx.internal.operators

Classes in rx.internal.operators that implement Observer

Modifier and Type	Class	Description
(package private) static final class	BlockingOperatorLatest.LatestObserverIterator<T>	Observer of source, iterator for output.
(package private) static final class	BlockingOperatorMostRecent.MostRecentObserver<T>
(package private) static final class	BlockingOperatorNext.NextObserver<T>
static final class	BlockingOperatorToIterator.SubscriberIterator<T>
final class	BufferUntilSubscriber<T>	A solution to the "time gap" problem that occurs with groupBy and pivot.
(package private) static final class	CachedObservable.CacheState<T>	Contains the active child producers and the values to replay.
(package private) static final class	CompletableOnSubscribeConcat.CompletableConcatSubscriber
(package private) static final class	CompletableOnSubscribeMerge.CompletableMergeSubscriber
class	DeferredScalarSubscriber<T,R>	Base class for Subscribers that consume the entire upstream and signal zero or one element (or an error) in a backpressure honoring fashion.
(package private) static final class	OnSubscribeAmb.AmbSubscriber<T>
(package private) static final class	OnSubscribeCollect.CollectSubscriber<T,R>
(package private) static final class	OnSubscribeCombineLatest.CombinerSubscriber<T,R>
(package private) static final class	OnSubscribeConcatMap.ConcatMapInnerSubscriber<T,R>
(package private) static final class	OnSubscribeConcatMap.ConcatMapSubscriber<T,R>
(package private) static final class	OnSubscribeDetach.DetachSubscriber<T>	The parent subscriber that forwards events and cleans up on a terminal state.
(package private) static final class	OnSubscribeFilter.FilterSubscriber<T>
(package private) static final class	OnSubscribeFlattenIterable.FlattenIterableSubscriber<T,R>
(package private) static class	OnSubscribeFromAsync.BaseAsyncEmitter<T>
(package private) static final class	OnSubscribeFromAsync.BufferAsyncEmitter<T>
(package private) static final class	OnSubscribeFromAsync.DropAsyncEmitter<T>
(package private) static final class	OnSubscribeFromAsync.ErrorAsyncEmitter<T>
(package private) static final class	OnSubscribeFromAsync.LatestAsyncEmitter<T>
(package private) static final class	OnSubscribeFromAsync.NoneAsyncEmitter<T>
(package private) static class	OnSubscribeFromAsync.NoOverflowBaseAsyncEmitter<T>
(package private) final class	OnSubscribeGroupJoin.ResultManager.LeftDurationObserver	Observe left duration and apply termination.
(package private) final class	OnSubscribeGroupJoin.ResultManager.LeftObserver	Observe the left source.
(package private) final class	OnSubscribeGroupJoin.ResultManager.RightDurationObserver	Observe right duration and apply termination.
(package private) final class	OnSubscribeGroupJoin.ResultManager.RightObserver	Observe the right source.
(package private) final class	OnSubscribeGroupJoin.WindowObservableFunc.WindowSubscriber	Observe activities on the window.
(package private) final class	OnSubscribeJoin.ResultSink.LeftSubscriber	Observes the left values.
(package private) final class	OnSubscribeJoin.ResultSink.LeftSubscriber.LeftDurationSubscriber	Observes the left duration.
(package private) final class	OnSubscribeJoin.ResultSink.RightSubscriber	Observes the right values.
(package private) final class	OnSubscribeJoin.ResultSink.RightSubscriber.RightDurationSubscriber	Observe the right duration.
(package private) static final class	OnSubscribeMap.MapSubscriber<T,R>
(package private) static final class	OnSubscribeOnAssembly.OnAssemblySubscriber<T>
final class	OnSubscribePublishMulticast<T>	Multicasts notifications coming through its input Subscriber view to its client Subscribers via lockstep backpressure mode.
(package private) static final class	OnSubscribePublishMulticast.ParentSubscriber<T>	The subscriber that must be used for subscribing to the upstream source.
(package private) static final class	OnSubscribeReduce.ReduceSubscriber<T>
(package private) static final class	OnSubscribeReduceSeed.ReduceSeedSubscriber<T,R>
(package private) static final class	OnSubscribeTakeLastOne.TakeLastOneSubscriber<T>
(package private) final class	OperatorBufferWithSingleObservable.BufferingSubscriber
(package private) static final class	OperatorBufferWithSize.BufferExact<T>
(package private) static final class	OperatorBufferWithSize.BufferOverlap<T>
(package private) static final class	OperatorBufferWithSize.BufferSkip<T>
(package private) final class	OperatorBufferWithStartEndObservable.BufferingSubscriber
(package private) final class	OperatorBufferWithTime.ExactSubscriber	Subscriber when exact timed chunking is required.
(package private) final class	OperatorBufferWithTime.InexactSubscriber	Subscriber when the buffer chunking time and length differ.
(package private) static final class	OperatorCast.CastSubscriber<T,R>
(package private) static final class	OperatorDoOnRequest.ParentSubscriber<T>
(package private) static final class	OperatorEagerConcatMap.EagerInnerSubscriber<T>
(package private) static final class	OperatorEagerConcatMap.EagerOuterSubscriber<T,R>
static final class	OperatorGroupBy.GroupBySubscriber<T,K,V>
(package private) static final class	OperatorMapNotification.MapNotificationSubscriber<T,R>
(package private) static final class	OperatorMapPair.MapPairSubscriber<T,U,R>
(package private) static class	OperatorMaterialize.ParentSubscriber<T>
(package private) static final class	OperatorMerge.InnerSubscriber<T>
(package private) static final class	OperatorMerge.MergeSubscriber<T>	The subscriber that observes Observables.
(package private) static final class	OperatorObserveOn.ObserveOnSubscriber<T>	Observe through individual queue per observer.
(package private) static final class	OperatorOnBackpressureBuffer.BufferSubscriber<T>
(package private) static final class	OperatorOnBackpressureLatest.LatestEmitter<T>	A terminable producer which emits the latest items on request.
(package private) static final class	OperatorOnBackpressureLatest.LatestSubscriber<T>
(package private) static final class	OperatorPublish.PublishSubscriber<T>
(package private) static final class	OperatorReplay.ReplaySubscriber<T>
(package private) static final class	OperatorRetryWithPredicate.SourceSubscriber<T>
(package private) static final class	OperatorSampleWithTime.SamplerSubscriber<T>	The source subscriber and sampler.
(package private) static final class	OperatorScan.InitialProducer<R>
(package private) static final class	OperatorSingle.ParentSubscriber<T>
(package private) static final class	OperatorSwitch.InnerSubscriber<T>
(package private) static final class	OperatorSwitch.SwitchSubscriber<T>
(package private) static final class	OperatorSwitchIfEmpty.AlternateSubscriber<T>
(package private) static final class	OperatorSwitchIfEmpty.ParentSubscriber<T>
(package private) static final class	OperatorTakeLast.TakeLastSubscriber<T>
(package private) static final class	OperatorTakeLastTimed.TakeLastTimedSubscriber<T>
(package private) static final class	OperatorTakeTimed.TakeSubscriber<T>	Subscribed to source and scheduled on a worker.
(package private) final class	OperatorTakeUntilPredicate.ParentSubscriber	Subscriber returned to the upstream.
(package private) static final class	OperatorTimeoutBase.TimeoutSubscriber<T>
(package private) static final class	OperatorWindowWithObservable.BoundarySubscriber<T,U>	Observes the boundary.
(package private) static final class	OperatorWindowWithObservable.SourceSubscriber<T>	Observes the source.
(package private) static final class	OperatorWindowWithObservableFactory.BoundarySubscriber<T,U>	Observes the boundary.
(package private) static final class	OperatorWindowWithObservableFactory.SourceSubscriber<T,U>	Observes the source.
(package private) static final class	OperatorWindowWithSize.WindowExact<T>
(package private) static final class	OperatorWindowWithSize.WindowOverlap<T>
(package private) static final class	OperatorWindowWithSize.WindowSkip<T>
(package private) final class	OperatorWindowWithStartEndObservable.SourceSubscriber
(package private) final class	OperatorWindowWithTime.ExactSubscriber	Subscriber with exact, non-overlapping windows.
(package private) final class	OperatorWindowWithTime.InexactSubscriber	Subscriber with inexact, potentially overlapping or discontinuous windows.
(package private) static final class	OperatorWithLatestFromMany.WithLatestMainSubscriber<T,R>
(package private) static final class	OperatorWithLatestFromMany.WithLatestOtherSubscriber
(package private) final class	OperatorZip.Zip.InnerSubscriber
(package private) final class	OperatorZip.ZipSubscriber

Fields in rx.internal.operators declared as Observer

Modifier and Type	Field	Description
(package private) final Observer<? super R>	OperatorZip.Zip.child
(package private) Observer<T>	OperatorWindowWithObservable.SourceSubscriber.consumer	Accessed from the serialized part.
(package private) Observer<T>	OperatorWindowWithObservableFactory.SourceSubscriber.consumer	Accessed from the serialized part.
(package private) final Observer<T>	OperatorWindowWithStartEndObservable.SerializedSubject.consumer
(package private) final Observer<T>	OperatorWindowWithTime.CountedSerializedSubject.consumer
(package private) final Observer<T>	OperatorWindowWithTime.State.consumer
(package private) final Observer<? super T>	OperatorDoOnEach.doOnEachObserver
(package private) static final Observer	BufferUntilSubscriber.EMPTY_OBSERVER

Fields in rx.internal.operators with type parameters of type Observer

Modifier and Type	Field	Description
(package private) final Map<Integer,Observer<T2>>	OnSubscribeGroupJoin.ResultManager.leftMap	Guarded by guard.

Methods in rx.internal.operators with parameters of type Observer

Modifier and Type	Method	Description
boolean	NotificationLite.accept(Observer<? super T> o, Object n)	Unwraps the lite notification and calls the appropriate method on the Observer.
(package private) boolean	BufferUntilSubscriber.State.casObserverRef(Observer<? super T> expected, Observer<? super T> next)
OperatorWindowWithTime.State<T>	OperatorWindowWithTime.State.create(Observer<T> consumer, Observable<T> producer)

Method parameters in rx.internal.operators with type arguments of type Observer

Modifier and Type	Method	Description
(package private) void	OnSubscribeGroupJoin.ResultManager.complete(List<Observer<T2>> list)

Constructors in rx.internal.operators with parameters of type Observer

Modifier	Constructor	Description
	CountedSerializedSubject(Observer<T> consumer, Observable<T> producer)
	OperatorDoOnEach(Observer<? super T> doOnEachObserver)
	SerializedSubject(Observer<T> consumer, Observable<T> producer)
	State(Observer<T> consumer, Observable<T> producer, int count)

Uses of Observer in rx.internal.producers

Classes in rx.internal.producers that implement Observer

Modifier and Type	Class	Description
final class	ProducerObserverArbiter<T>	Producer that serializes any event emission with requesting and producer changes.
final class	QueuedProducer<T>	Producer that holds an unbounded (or custom) queue, handles terminal events, enqueues values and relays them to a child subscriber on request.

Uses of Observer in rx.internal.schedulers

Fields in rx.internal.schedulers declared as Observer

Modifier and Type	Field	Description
private final Observer<Observable<Completable>>	SchedulerWhen.workerObserver

Uses of Observer in rx.internal.util

Classes in rx.internal.util that implement Observer

Modifier and Type	Class	Description
final class	ActionNotificationObserver<T>	An Observer that forwards the onXXX method calls to a notification callback by transforming each signal type into Notifications.
final class	ActionSubscriber<T>	A Subscriber that forwards the onXXX method calls to callbacks.
final class	ObserverSubscriber<T>	Wraps an Observer and forwards the onXXX method calls to it.

Fields in rx.internal.util declared as Observer

Modifier and Type	Field	Description
(package private) final Observer<? super T>	ObserverSubscriber.observer

Methods in rx.internal.util with parameters of type Observer

Modifier and Type	Method	Description
boolean	RxRingBuffer.accept(Object o, Observer child)

Constructors in rx.internal.util with parameters of type Observer

Modifier	Constructor	Description
	ObserverSubscriber(Observer<? super T> observer)

Uses of Observer in rx.observables

Classes in rx.observables that implement Observer

Modifier and Type	Class	Description
(package private) static final class	AsyncOnSubscribe.AsyncOuterManager<S,T>
(package private) static final class	AsyncOnSubscribe.UnicastSubject<T>
(package private) static final class	SyncOnSubscribe.SubscriptionProducer<S,T>	Contains the producer loop that reacts to downstream requests of work.

Fields in rx.observables with type parameters of type Observer

Modifier and Type	Field	Description
private final Func3<? super S,Long,? super Observer<Observable<? extends T>>,? extends S>	AsyncOnSubscribe.AsyncOnSubscribeImpl.next
private final Func2<? super S,? super Observer<? super T>,? extends S>	SyncOnSubscribe.SyncOnSubscribeImpl.next

Methods in rx.observables with parameters of type Observer

Modifier and Type	Method	Description
protected S	AsyncOnSubscribe.AsyncOnSubscribeImpl.next(S state, long requested, Observer<Observable<? extends T>> observer)
protected abstract S	AsyncOnSubscribe.next(S state, long requested, Observer<Observable<? extends T>> observer)	Called to produce data to the downstream subscribers.
protected abstract S	SyncOnSubscribe.next(S state, Observer<? super T> observer)	Called to produce data to the downstream subscribers.
protected S	SyncOnSubscribe.SyncOnSubscribeImpl.next(S state, Observer<? super T> observer)
void	BlockingObservable.subscribe(Observer<? super T> observer)	Subscribes to the source and calls back the Observer methods on the current thread.

Method parameters in rx.observables with type arguments of type Observer

Modifier and Type	Method	Description
static <S, T> AsyncOnSubscribe<S,T>	AsyncOnSubscribe.createSingleState(Func0<? extends S> generator, Action3<? super S,Long,? super Observer<Observable<? extends T>>> next)	Generates a synchronous AsyncOnSubscribe that calls the provided next function to generate data to downstream subscribers.
static <S, T> AsyncOnSubscribe<S,T>	AsyncOnSubscribe.createSingleState(Func0<? extends S> generator, Action3<? super S,Long,? super Observer<Observable<? extends T>>> next, Action1<? super S> onUnsubscribe)	Generates a synchronous AsyncOnSubscribe that calls the provided next function to generate data to downstream subscribers.
static <S, T> SyncOnSubscribe<S,T>	SyncOnSubscribe.createSingleState(Func0<? extends S> generator, Action2<? super S,? super Observer<? super T>> next)	Generates a synchronous SyncOnSubscribe that calls the provided next function to generate data to downstream subscribers.
static <S, T> SyncOnSubscribe<S,T>	SyncOnSubscribe.createSingleState(Func0<? extends S> generator, Action2<? super S,? super Observer<? super T>> next, Action1<? super S> onUnsubscribe)	Generates a synchronous SyncOnSubscribe that calls the provided next function to generate data to downstream subscribers.
static <S, T> AsyncOnSubscribe<S,T>	AsyncOnSubscribe.createStateful(Func0<? extends S> generator, Func3<? super S,Long,? super Observer<Observable<? extends T>>,? extends S> next)	Generates a synchronous AsyncOnSubscribe that calls the provided next function to generate data to downstream subscribers.
static <S, T> AsyncOnSubscribe<S,T>	AsyncOnSubscribe.createStateful(Func0<? extends S> generator, Func3<? super S,Long,? super Observer<Observable<? extends T>>,? extends S> next, Action1<? super S> onUnsubscribe)	Generates a synchronous AsyncOnSubscribe that calls the provided next function to generate data to downstream subscribers.
static <S, T> SyncOnSubscribe<S,T>	SyncOnSubscribe.createStateful(Func0<? extends S> generator, Func2<? super S,? super Observer<? super T>,? extends S> next)	Generates a synchronous SyncOnSubscribe that calls the provided next function to generate data to downstream subscribers.
static <S, T> SyncOnSubscribe<S,T>	SyncOnSubscribe.createStateful(Func0<? extends S> generator, Func2<? super S,? super Observer<? super T>,? extends S> next, Action1<? super S> onUnsubscribe)	Generates a synchronous SyncOnSubscribe that calls the provided next function to generate data to downstream subscribers.
static <T> AsyncOnSubscribe<Void,T>	AsyncOnSubscribe.createStateless(Action2<Long,? super Observer<Observable<? extends T>>> next)	Generates a synchronous AsyncOnSubscribe that calls the provided next function to generate data to downstream subscribers.
static <T> AsyncOnSubscribe<Void,T>	AsyncOnSubscribe.createStateless(Action2<Long,? super Observer<Observable<? extends T>>> next, Action0 onUnsubscribe)	Generates a synchronous AsyncOnSubscribe that calls the provided next function to generate data to downstream subscribers.
static <T> SyncOnSubscribe<Void,T>	SyncOnSubscribe.createStateless(Action1<? super Observer<? super T>> next)	Generates a synchronous SyncOnSubscribe that calls the provided next function to generate data to downstream subscribers.
static <T> SyncOnSubscribe<Void,T>	SyncOnSubscribe.createStateless(Action1<? super Observer<? super T>> next, Action0 onUnsubscribe)	Generates a synchronous SyncOnSubscribe that calls the provided next function to generate data to downstream subscribers.

Constructor parameters in rx.observables with type arguments of type Observer

Modifier	Constructor	Description
	AsyncOnSubscribeImpl(Func0<? extends S> generator, Func3<? super S,Long,? super Observer<Observable<? extends T>>,? extends S> next)
(package private)	AsyncOnSubscribeImpl(Func0<? extends S> generator, Func3<? super S,Long,? super Observer<Observable<? extends T>>,? extends S> next, Action1<? super S> onUnsubscribe)
	AsyncOnSubscribeImpl(Func3<S,Long,Observer<Observable<? extends T>>,S> nextFunc)
	AsyncOnSubscribeImpl(Func3<S,Long,Observer<Observable<? extends T>>,S> next, Action1<? super S> onUnsubscribe)
	SyncOnSubscribeImpl(Func0<? extends S> generator, Func2<? super S,? super Observer<? super T>,? extends S> next)
(package private)	SyncOnSubscribeImpl(Func0<? extends S> generator, Func2<? super S,? super Observer<? super T>,? extends S> next, Action1<? super S> onUnsubscribe)
	SyncOnSubscribeImpl(Func2<S,Observer<? super T>,S> nextFunc)
	SyncOnSubscribeImpl(Func2<S,Observer<? super T>,S> next, Action1<? super S> onUnsubscribe)

Uses of Observer in rx.observers

Classes in rx.observers that implement Observer

Modifier and Type	Class	Description
class	SafeSubscriber<T>	SafeSubscriber is a wrapper around Subscriber that ensures that the Subscriber complies with the Observable contract.
class	SerializedObserver<T>	Enforces single-threaded, serialized, ordered execution of SerializedObserver.onNext(T), SerializedObserver.onCompleted(), and SerializedObserver.onError(java.lang.Throwable).
class	SerializedSubscriber<T>	Enforces single-threaded, serialized, ordered execution of SerializedSubscriber.onNext(T), SerializedSubscriber.onCompleted(), and SerializedSubscriber.onError(java.lang.Throwable).
class	TestObserver<T>	Deprecated. use the TestSubscriber insteand.
class	TestSubscriber<T>	A TestSubscriber is a variety of Subscriber that you can use for unit testing, to perform assertions, inspect received events, or wrap a mocked Subscriber.

Fields in rx.observers declared as Observer

Modifier and Type	Field	Description
private final Observer<? super T>	SerializedObserver.actual
private final Observer<T>	TestObserver.delegate	Deprecated.
private final Observer<T>	TestSubscriber.delegate
private static final Observer<Object>	Observers.EMPTY
private static final Observer<Object>	TestObserver.INERT	Deprecated.
private static final Observer<Object>	TestSubscriber.INERT	The shared no-op observer.
private final Observer<T>	SerializedSubscriber.s

Methods in rx.observers that return Observer

Modifier and Type	Method	Description
static <T> Observer<T>	Observers.create(Action1<? super T> onNext)	Creates an Observer that receives the emissions of any Observable it subscribes to via onNext but ignores onCompleted notifications; it will throw an OnErrorNotImplementedException if onError is invoked.
static <T> Observer<T>	Observers.create(Action1<? super T> onNext, Action1<Throwable> onError)	Creates an Observer that receives the emissions of any Observable it subscribes to via onNext and handles any onError notification but ignores an onCompleted notification.
static <T> Observer<T>	Observers.create(Action1<? super T> onNext, Action1<Throwable> onError, Action0 onComplete)	Creates an Observer that receives the emissions of any Observable it subscribes to via onNext and handles any onError or onCompleted notifications.
static <T> Observer<T>	Observers.empty()	Returns an inert Observer that does nothing in response to the emissions or notifications from any Observable it subscribes to but will throw an exception if its onError method is called.

Methods in rx.observers with parameters of type Observer

Modifier and Type	Method	Description
static <T> TestSubscriber<T>	TestSubscriber.create(Observer<T> delegate)	Factory method to construct a TestSubscriber which delegates events to the given Observer and an issues an initial request of Long.MAX_VALUE.
static <T> TestSubscriber<T>	TestSubscriber.create(Observer<T> delegate, long initialRequest)	Factory method to construct a TestSubscriber which delegates events to the given Observer and issues the given initial request amount.
static <T> Subscriber<T>	Subscribers.from(Observer<? super T> o)	Converts an Observer into a Subscriber.

Constructors in rx.observers with parameters of type Observer

Modifier	Constructor	Description
	SerializedObserver(Observer<? super T> s)
	TestObserver(Observer<T> delegate)	Deprecated.
	TestSubscriber(Observer<T> delegate)	Constructs a TestSubscriber which requests Long.MAX_VALUE and delegates events to the given Observer.
	TestSubscriber(Observer<T> delegate, long initialRequest)	Constructs a TestSubscriber with the initial request to be requested from upstream and a delegate Observer to wrap.

Uses of Observer in rx.subjects

Classes in rx.subjects that implement Observer

Modifier and Type	Class	Description
final class	AsyncSubject<T>	Subject that publishes only the last item observed to each Observer once the source Observable has completed.
final class	BehaviorSubject<T>	Subject that emits the most recent item it has observed and all subsequent observed items to each subscribed Observer.
final class	PublishSubject<T>	Subject that, once an Observer has subscribed, emits all subsequently observed items to the subscriber.
final class	ReplaySubject<T>	Subject that buffers all items it observes and replays them to any Observer that subscribes.
(package private) static final class	ReplaySubject.ReplayState<T>	Holds onto the array of Subscriber-wrapping ReplayProducers and the buffer that holds values to be replayed; it manages subscription and signal dispatching.
class	SerializedSubject<T,R>	Wraps a Subject so that it is safe to call its various on methods from different threads.
class	Subject<T,R>	Represents an object that is both an Observable and an Observer.
protected static final class	SubjectSubscriptionManager.SubjectObserver<T>	Observer wrapping the actual Subscriber and providing various emission facilities.
final class	TestSubject<T>	A variety of Subject that is useful for testing purposes.
final class	UnicastSubject<T>	A Subject variant which buffers events until a single Subscriber arrives and replays them to it and potentially switches to direct delivery once the Subscriber caught up and requested an unlimited amount.
(package private) static final class	UnicastSubject.State<T>	The single-consumption replaying state.

Methods in rx.subjects that return Observer

Modifier and Type	Method	Description
(package private) Observer<? super T>	SubjectSubscriptionManager.SubjectObserver.getActual()