T
- the value typepublic abstract class ResourceSingleObserver<T> extends Object implements SingleObserver<T>, Disposable
SingleObserver
that allows asynchronous cancellation of its subscription
and the associated resources.
All pre-implemented final methods are thread-safe.
Override the protected onStart()
to perform initialization when this
ResourceSingleObserver
is subscribed to a source.
Use the public dispose()
method to dispose the sequence externally and release
all resources.
To release the associated resources, one has to call dispose()
in onSuccess()
and onError()
explicitly.
Use add(Disposable)
to associate resources (as Disposable
s)
with this ResourceSingleObserver
that will be cleaned up when dispose()
is called.
Removing previously associated resources is not possible but one can create a
CompositeDisposable
, associate it with this
ResourceSingleObserver
and then add/remove resources to/from the CompositeDisposable
freely.
Like all other consumers, ResourceSingleObserver
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()
, SingleObserver.onSuccess(Object)
and SingleObserver.onError(Throwable)
are not allowed to throw any unchecked exceptions.
Example
Disposable d =
Single.just(1).delay(1, TimeUnit.SECONDS)
.subscribeWith(new ResourceSingleObserver<Integer>() {
@Override public void onStart() {
add(Schedulers.single()
.scheduleDirect(() -> System.out.println("Time!"),
2, TimeUnit.SECONDS));
}
@Override public void onSuccess(Integer t) {
System.out.println(t);
dispose();
}
@Override public void onError(Throwable t) {
t.printStackTrace();
dispose();
}
});
// ...
d.dispose();
Constructor and Description |
---|
ResourceSingleObserver() |
Modifier and Type | Method and Description |
---|---|
void |
add(Disposable resource)
Adds a resource to this ResourceObserver.
|
void |
dispose()
Cancels the main disposable (if any) and disposes the resources associated with
this ResourceObserver (if any).
|
boolean |
isDisposed()
Returns true if this ResourceObserver has been disposed/cancelled.
|
protected void |
onStart()
Called once the upstream sets a Subscription on this ResourceObserver.
|
void |
onSubscribe(Disposable d)
Provides the SingleObserver with the means of cancelling (disposing) the
connection (channel) with the Single in both
synchronous (from within
onSubscribe(Disposable) itself) and asynchronous manner. |
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
onError, onSuccess
public final void add(@NonNull Disposable resource)
resource
- the resource to addNullPointerException
- if resource is nullpublic final void onSubscribe(@NonNull Disposable d)
SingleObserver
onSubscribe(Disposable)
itself) and asynchronous manner.onSubscribe
in interface SingleObserver<T>
d
- the Disposable instance whose Disposable.dispose()
can
be called anytime to cancel the connectionprotected void onStart()
You can perform initialization at this moment. The default implementation does nothing.
public final void dispose()
This method can be called before the upstream calls onSubscribe at which case the main Disposable will be immediately disposed.
dispose
in interface Disposable
public final boolean isDisposed()
isDisposed
in interface Disposable