rx

Interface Observer<T>

Type Parameters:

T - the type of item the Observer expects to observe

All Known Subinterfaces:

AssertableSubscriber<T>, Emitter<T>

All Known Implementing Classes:

AsyncSubject, BehaviorSubject, PublishSubject, ReplaySubject, SafeSubscriber, SerializedObserver, SerializedSubject, SerializedSubscriber, Subject, Subscriber, TestObserver, TestSubject, TestSubscriber, UnicastSubject

public interface Observer<T>

Provides a mechanism for receiving push-based notifications.

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

See Also:

ReactiveX documentation: Observable

Method Summary

Modifier and Type	Method and Description
void	onCompleted() Notifies the Observer that the Observable has finished sending push-based notifications.
void	onError(java.lang.Throwable e) Notifies the Observer that the Observable has experienced an error condition.
void	onNext(T t) Provides the Observer with a new item to observe.

Method Detail

onCompleted

void onCompleted()

Notifies the Observer that the Observable has finished sending push-based notifications.

The Observable will not call this method if it calls onError(java.lang.Throwable).

onError

void onError(java.lang.Throwable e)

Notifies the Observer that the Observable has experienced an error condition.

If the Observable calls this method, it will not thereafter call onNext(T) or onCompleted().

Parameters:

e - the exception encountered by the Observable

onNext

void onNext(T t)

Provides the Observer with a new item to observe.

The Observable may call this method 0 or more times.

The Observable will not call this method again after it calls either onCompleted() or onError(java.lang.Throwable).

Parameters:

t - the item emitted by the Observable