Request the Publisher to stop sending data and clean up resources.
Request the Publisher to stop sending data and clean up resources.
Data may still be sent to meet previously signalled demand after calling cancel as this request is asynchronous.
No events will be sent by a Publisher until demand is signaled via this method.
No events will be sent by a Publisher until demand is signaled via this method.
It can be called however often and whenever needed. Whatever has been requested can be sent by the Publisher so only signal demand for what can be safely handled.
A Publisher can send less than is requested if the stream ends but
then must emit either onError
or onComplete
.
The Subscriber MAY call this method synchronously in the implementation of its
onSubscribe
/ onNext
methods, therefore the effects of this function must be
asynchronous, otherwise it could lead to a stack overflow.
signals demand for the number of onNext
events that the Subscriber wants,
if positive, then the Publisher is bound by contract to not send more than
this number of onNext
events and if negative, then this signals to the
Publisher that it may send an infinite number of events, until the subscription
gets cancelled or the stream is complete.
Represents a one-to-one lifecycle of a Subscriber subscribing to a Publisher and mirrors the
Subscription
interface from the Reactive Streams specification.It can be used only once by a single Subscriber. It is used for both signaling demand for data and for canceling demand (and allow resource cleanup).