Class AsyncSubject<T>
- java.lang.Object
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- rx.Observable<R>
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- rx.subjects.Subject<T,T>
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- rx.subjects.AsyncSubject<T>
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- Type Parameters:
T
- the type of item expected to be observed by the Subject
- All Implemented Interfaces:
Observer<T>
public final class AsyncSubject<T> extends Subject<T,T>
Subject that publishes only the last item observed to eachObserver
once the sourceObservable
has completed. The item is cached and published to anyObserver
s which subscribe after the source has completed. If the source emitted no items,AsyncSubject
completes without emitting anything. If the source terminated in an error, current and future subscribers will receive only the error.Example usage:
// observer will receive no onNext events because the subject.onCompleted() isn't called. AsyncSubject<Object> subject = AsyncSubject.create(); subject.subscribe(observer); subject.onNext("one"); subject.onNext("two"); subject.onNext("three"); // observer will receive "three" as the only onNext event. AsyncSubject<Object> subject = AsyncSubject.create(); subject.subscribe(observer); subject.onNext("one"); subject.onNext("two"); subject.onNext("three"); subject.onCompleted();
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Nested Class Summary
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Nested classes/interfaces inherited from class rx.Observable
Observable.OnSubscribe<T>, Observable.Operator<R,T>, Observable.Transformer<T,R>
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Field Summary
Fields Modifier and Type Field Description (package private) java.lang.Object
lastValue
private NotificationLite<T>
nl
(package private) SubjectSubscriptionManager<T>
state
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Constructor Summary
Constructors Modifier Constructor Description protected
AsyncSubject(Observable.OnSubscribe<T> onSubscribe, SubjectSubscriptionManager<T> state)
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Method Summary
All Methods Static Methods Instance Methods Concrete Methods Modifier and Type Method Description static <T> AsyncSubject<T>
create()
Creates and returns a newAsyncSubject
.java.lang.Throwable
getThrowable()
Returns the Throwable that terminated the Subject.T
getValue()
Returns the current value of the Subject if there is such a value and the subject hasn't terminated with an exception.boolean
hasCompleted()
Check if the Subject has terminated normally.boolean
hasObservers()
boolean
hasThrowable()
Check if the Subject has terminated with an exception.boolean
hasValue()
Check if the Subject has a value.void
onCompleted()
Notifies the Observer that theObservable
has finished sending push-based notifications.void
onError(java.lang.Throwable e)
Notifies the Observer that theObservable
has experienced an error condition.void
onNext(T v)
Provides the Observer with a new item to observe.-
Methods inherited from class rx.subjects.Subject
toSerialized
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Methods inherited from class rx.Observable
all, amb, amb, amb, amb, amb, amb, amb, amb, amb, ambWith, asObservable, buffer, buffer, buffer, buffer, buffer, buffer, buffer, buffer, buffer, buffer, buffer, buffer, cache, cache, cacheWithInitialCapacity, cast, collect, combineLatest, combineLatest, combineLatest, combineLatest, combineLatest, combineLatest, combineLatest, combineLatest, combineLatest, combineLatest, combineLatestDelayError, compose, concat, concat, concat, concat, concat, concat, concat, concat, concat, concatDelayError, concatDelayError, concatEager, concatEager, concatEager, concatEager, concatEager, concatEager, concatEager, concatEager, concatEager, concatEager, concatEager, concatEager, concatMap, concatMapDelayError, concatMapEager, concatMapEager, concatMapEager, concatMapIterable, concatWith, contains, count, countLong, create, create, create, debounce, debounce, debounce, defaultIfEmpty, defer, delay, delay, delay, delay, delaySubscription, delaySubscription, delaySubscription, delaySubscription, dematerialize, distinct, distinct, distinctUntilChanged, distinctUntilChanged, distinctUntilChanged, doAfterTerminate, doOnCompleted, doOnEach, doOnEach, doOnError, doOnNext, doOnRequest, doOnSubscribe, doOnTerminate, doOnUnsubscribe, elementAt, elementAtOrDefault, empty, error, exists, extend, filter, finallyDo, first, first, firstOrDefault, firstOrDefault, flatMap, flatMap, flatMap, flatMap, flatMap, flatMap, flatMapIterable, flatMapIterable, flatMapIterable, flatMapIterable, forEach, forEach, forEach, from, from, from, from, from, fromAsync, fromCallable, groupBy, groupBy, groupBy, groupJoin, ignoreElements, interval, interval, interval, interval, isEmpty, join, just, just, just, just, just, just, just, just, just, just, last, last, lastOrDefault, lastOrDefault, lift, limit, map, materialize, merge, merge, merge, merge, merge, merge, merge, merge, merge, merge, merge, merge, merge, merge, mergeDelayError, mergeDelayError, mergeDelayError, mergeDelayError, mergeDelayError, mergeDelayError, mergeDelayError, mergeDelayError, mergeDelayError, mergeDelayError, mergeDelayError, mergeDelayError, mergeWith, nest, never, observeOn, observeOn, observeOn, observeOn, ofType, onBackpressureBuffer, onBackpressureBuffer, onBackpressureBuffer, onBackpressureBuffer, onBackpressureDrop, onBackpressureDrop, onBackpressureLatest, onErrorResumeNext, onErrorResumeNext, onErrorReturn, onExceptionResumeNext, onTerminateDetach, publish, publish, range, range, rebatchRequests, reduce, reduce, repeat, repeat, repeat, repeat, repeatWhen, repeatWhen, replay, replay, replay, replay, replay, replay, replay, replay, replay, replay, replay, replay, replay, replay, replay, replay, retry, retry, retry, retryWhen, retryWhen, sample, sample, sample, scan, scan, sequenceEqual, sequenceEqual, serialize, share, single, single, singleOrDefault, singleOrDefault, skip, skip, skip, skipLast, skipLast, skipLast, skipUntil, skipWhile, startWith, startWith, startWith, startWith, startWith, startWith, startWith, startWith, startWith, startWith, startWith, subscribe, subscribe, subscribe, subscribe, subscribe, subscribe, subscribeOn, switchIfEmpty, switchMap, switchMapDelayError, switchOnNext, switchOnNextDelayError, take, take, take, takeFirst, takeLast, takeLast, takeLast, takeLast, takeLast, takeLastBuffer, takeLastBuffer, takeLastBuffer, takeLastBuffer, takeLastBuffer, takeUntil, takeUntil, takeWhile, throttleFirst, throttleFirst, throttleLast, throttleLast, throttleWithTimeout, throttleWithTimeout, timeInterval, timeInterval, timeout, timeout, timeout, timeout, timeout, timeout, timeout, timeout, timer, timer, timer, timer, timestamp, timestamp, toBlocking, toCompletable, toList, toMap, toMap, toMap, toMultimap, toMultimap, toMultimap, toMultimap, toSingle, toSortedList, toSortedList, toSortedList, toSortedList, unsafeSubscribe, unsubscribeOn, using, using, window, window, window, window, window, window, window, window, window, window, window, window, withLatestFrom, withLatestFrom, withLatestFrom, withLatestFrom, withLatestFrom, withLatestFrom, withLatestFrom, withLatestFrom, withLatestFrom, withLatestFrom, zip, zip, zip, zip, zip, zip, zip, zip, zip, zip, zip, zipWith, zipWith
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Field Detail
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state
final SubjectSubscriptionManager<T> state
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lastValue
volatile java.lang.Object lastValue
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nl
private final NotificationLite<T> nl
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Constructor Detail
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AsyncSubject
protected AsyncSubject(Observable.OnSubscribe<T> onSubscribe, SubjectSubscriptionManager<T> state)
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Method Detail
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create
public static <T> AsyncSubject<T> create()
Creates and returns a newAsyncSubject
.- Type Parameters:
T
- the result value type- Returns:
- the new
AsyncSubject
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onCompleted
public void onCompleted()
Description copied from interface:Observer
Notifies the Observer that theObservable
has finished sending push-based notifications.The
Observable
will not call this method if it callsObserver.onError(java.lang.Throwable)
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onError
public void onError(java.lang.Throwable e)
Description copied from interface:Observer
Notifies the Observer that theObservable
has experienced an error condition.If the
Observable
calls this method, it will not thereafter callObserver.onNext(T)
orObserver.onCompleted()
.- Parameters:
e
- the exception encountered by the Observable
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onNext
public void onNext(T v)
Description copied from interface:Observer
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 eitherObserver.onCompleted()
orObserver.onError(java.lang.Throwable)
.- Parameters:
v
- the item emitted by the Observable
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hasObservers
public boolean hasObservers()
Description copied from class:Subject
- Specified by:
hasObservers
in classSubject<T,T>
- Returns:
- true if there is at least one Observer subscribed to this Subject, false otherwise
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hasValue
@Beta public boolean hasValue()
Check if the Subject has a value.Use the
getValue()
method to retrieve such a value.Note that unless
hasCompleted()
orhasThrowable()
returns true, the value retrieved bygetValue()
may get outdated.- Returns:
- true if and only if the subject has some value but not an error
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hasThrowable
@Beta public boolean hasThrowable()
Check if the Subject has terminated with an exception.- Returns:
- true if the subject has received a throwable through
onError
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hasCompleted
@Beta public boolean hasCompleted()
Check if the Subject has terminated normally.- Returns:
- true if the subject completed normally via
onCompleted()
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getValue
@Beta public T getValue()
Returns the current value of the Subject if there is such a value and the subject hasn't terminated with an exception.The method can return
null
for various reasons. UsehasValue()
,hasThrowable()
andhasCompleted()
to determine if suchnull
is a valid value, there was an exception or the Subject terminated without receiving any value.- Returns:
- the current value or
null
if the Subject doesn't have a value, has terminated with an exception or has an actualnull
as a value.
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getThrowable
@Beta public java.lang.Throwable getThrowable()
Returns the Throwable that terminated the Subject.- Returns:
- the Throwable that terminated the Subject or
null
if the subject hasn't terminated yet or it terminated normally.
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