AsyncSubjectsare subjects that produce either no values or a single value. If multiple values are produced via
onNext, only the last one is used. If
onErroris called, then no value is produced and
onErroris called on any subscribed Observers. If an Observer subscribes and the
AsyncSubjecthas already terminated, the
Observerwill immediately receive the value or the error.
- Constructors - API calls which return an object, typically one that offers API methods
- Methods - API calls which can only be made on an object returned by a constructor