T - the value type
Example
Flowable.range(1, 5)
.subscribe(new DefaultSubscriber<Integer>() {
@Override public void onStart() {
System.out.println("Start!");
request(1);
}
@Override public void onNext(Integer t) {
if (t == 3) {
cancel();
}
System.out.println(t);
request(1);
}
@Override public void onError(Throwable t) {
t.printStackTrace();
}
@Override public void onComplete() {
System.out.println("Done!");
}
});
public abstract class DefaultSubscriber<T> extends Object implements FlowableSubscriber<T>
Subscriber with
support for requesting via request(long), cancelling via
via cancel() (both synchronously) and calls onStart()
when the subscription happens.
All pre-implemented final methods are thread-safe.
The default onStart() requests Long.MAX_VALUE by default. Override
the method to request a custom positive amount.
Note that calling request(long) from onStart() may trigger
an immediate, asynchronous emission of data to Subscriber.onNext(Object). Make sure
all initialization happens before the call to request() in onStart().
Calling request(long) inside Subscriber.onNext(Object) can happen at any time
because by design, onNext calls from upstream are non-reentrant and non-overlapping.
Use the protected cancel() to cancel the sequence from within an
onNext implementation.
Like all other consumers, DefaultSubscriber can be subscribed only once.
Any subsequent attempt to subscribe it to a new source will yield an
IllegalStateException with message "It is not allowed to subscribe with a(n) <class name> multiple times.".
Implementation of onStart(), Subscriber.onNext(Object), Subscriber.onError(Throwable)
and Subscriber.onComplete() are not allowed to throw any unchecked exceptions.
If for some reason this can't be avoided, use Flowable.safeSubscribe(org.reactivestreams.Subscriber)
instead of the standard subscribe() method.
| Constructor and Description |
|---|
DefaultSubscriber() |
| Modifier and Type | Method and Description |
|---|---|
protected void |
cancel()
Cancels the upstream's Subscription.
|
protected void |
onStart()
Called once the subscription has been set on this observer; override this
to perform initialization or issue an initial request.
|
void |
onSubscribe(Subscription s)
Implementors of this method should make sure everything that needs
to be visible in
Subscriber.onNext(Object) is established before
calling Subscription.request(long). |
protected void |
request(long n)
Requests from the upstream Subscription.
|
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, waitonComplete, onError, onNextpublic final void onSubscribe(Subscription s)
FlowableSubscriberSubscriber.onNext(Object) is established before
calling Subscription.request(long). In practice this means
no initialization should happen after the request() call and
additional behavior is thread safe in respect to onNext.
onSubscribe in interface FlowableSubscriber<T>onSubscribe in interface Subscriber<T>protected final void request(long n)
n - the request amount, positiveprotected final void cancel()
protected void onStart()
The default implementation requests Long.MAX_VALUE.