Class ResourceMaybeObserver<T>
- Type Parameters:
T
- the value type
- All Implemented Interfaces:
MaybeObserver<T>
,Disposable
MaybeObserver
that allows asynchronous cancellation of its subscription and associated resources.
All pre-implemented final methods are thread-safe.
Note that MaybeObserver.onSuccess(Object)
, MaybeObserver.onError(Throwable)
and MaybeObserver.onComplete()
are
exclusive to each other, unlike a regular Observer
, and
onComplete()
is never called after an onSuccess()
.
Override the protected onStart()
to perform initialization when this
ResourceMaybeObserver
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()
, onError()
and onComplete()
explicitly.
Use add(Disposable)
to associate resources (as Disposable
s)
with this ResourceMaybeObserver
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
ResourceMaybeObserver
and then add/remove resources to/from the CompositeDisposable
freely.
Like all other consumers, ResourceMaybeObserver
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()
, MaybeObserver.onSuccess(Object)
, MaybeObserver.onError(Throwable)
and MaybeObserver.onComplete()
are not allowed to throw any unchecked exceptions.
Example
Disposable d =
Maybe.just(1).delay(1, TimeUnit.SECONDS)
.subscribeWith(new ResourceMaybeObserver<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();
}
@Override public void onComplete() {
System.out.println("Done!");
dispose();
}
});
// ...
d.dispose();
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Field Summary
FieldsModifier and TypeFieldDescriptionprivate final ListCompositeDisposable
The resource composite, can never be null.private final AtomicReference
<Disposable> The active subscription. -
Constructor Summary
Constructors -
Method Summary
Modifier and TypeMethodDescriptionfinal void
add
(@NonNull Disposable resource) Adds a resource to thisResourceMaybeObserver
.final void
dispose()
Cancels the main disposable (if any) and disposes the resources associated with thisResourceMaybeObserver
(if any).final boolean
Returns true if thisResourceMaybeObserver
has been disposed/cancelled.protected void
onStart()
Called once the upstream sets aDisposable
on thisResourceMaybeObserver
.final void
Provides theMaybeObserver
with the means of cancelling (disposing) the connection (channel) with theMaybe
in both synchronous (from withinonSubscribe(Disposable)
itself) and asynchronous manner.Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
Methods inherited from interface io.reactivex.rxjava3.core.MaybeObserver
onComplete, onError, onSuccess
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Field Details
-
upstream
The active subscription. -
resources
The resource composite, can never be null.
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Constructor Details
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ResourceMaybeObserver
public ResourceMaybeObserver()
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Method Details
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add
Adds a resource to thisResourceMaybeObserver
.- Parameters:
resource
- the resource to add- Throws:
NullPointerException
- if resource isnull
-
onSubscribe
Description copied from interface:MaybeObserver
Provides theMaybeObserver
with the means of cancelling (disposing) the connection (channel) with theMaybe
in both synchronous (from withinonSubscribe(Disposable)
itself) and asynchronous manner.- Specified by:
onSubscribe
in interfaceMaybeObserver<T>
- Parameters:
d
- theDisposable
instance whoseDisposable.dispose()
can be called anytime to cancel the connection
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onStart
protected void onStart()Called once the upstream sets aDisposable
on thisResourceMaybeObserver
.You can perform initialization at this moment. The default implementation does nothing.
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dispose
public final void dispose()Cancels the main disposable (if any) and disposes the resources associated with thisResourceMaybeObserver
(if any).This method can be called before the upstream calls
onSubscribe(Disposable)
at which case the mainDisposable
will be immediately disposed.- Specified by:
dispose
in interfaceDisposable
-
isDisposed
public final boolean isDisposed()Returns true if thisResourceMaybeObserver
has been disposed/cancelled.- Specified by:
isDisposed
in interfaceDisposable
- Returns:
- true if this
ResourceMaybeObserver
has been disposed/cancelled
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