T - the received value type.public abstract class DisposableSubscriber<T> extends java.lang.Object implements FlowableSubscriber<T>, Disposable
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. Use the protected request(long)
to request more items and cancel() to cancel the sequence from within an
onNext implementation.
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.
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 "Subscription already set!".
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.
Example
Disposable d =
Flowable.range(1, 5)
.subscribeWith(new DisposableSubscriber<Integer>() {
@Override public void onStart() {
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!");
}
});
// ...
d.dispose();
| Constructor and Description |
|---|
DisposableSubscriber() |
| Modifier and Type | Method and Description |
|---|---|
protected void |
cancel()
Cancels the Subscription set via onSubscribe or makes sure a
Subscription set asynchronously (later) is cancelled immediately.
|
void |
dispose()
Dispose the resource, the operation should be idempotent.
|
boolean |
isDisposed()
Returns true if this resource has been disposed.
|
protected void |
onStart()
Called once the single upstream Subscription is set via onSubscribe.
|
void |
onSubscribe(org.reactivestreams.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 the specified amount from the upstream if its Subscription is set via
onSubscribe already.
|
public final void onSubscribe(org.reactivestreams.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 org.reactivestreams.Subscriber<T>protected void onStart()
protected final void request(long n)
Note that calling this method before a Subscription is set via onSubscribe leads to NullPointerException and meant to be called from inside onStart or onNext.
n - the request amount, positiveprotected final void cancel()
This method is thread-safe and can be exposed as a public API.
public final boolean isDisposed()
DisposableisDisposed in interface Disposablepublic final void dispose()
Disposabledispose in interface Disposable