RxJava introduced Single<T>. How do I convert an Observable<T> to a Single<T>?
I think another answer is outdated. You should probably check the following methods.
singleOrError: Emits the one and only element, IndexOutOfBoundsException if the source is longer than 1 item or a NoSuchElementException if the source is empty.
firstOrError: Emits the first element or a NoSuchElementException if the source is empty.
lastOrError: Emits the lastelement or a NoSuchElementException if the source is empty.
elementAtOrError: Emits the indexth element or a NoSuchElementException.
More info on this page: https://github.com/ReactiveX/RxJava/wiki/What%27s-different-in-2.0
Note: This is for RxJava 1. See other answers below/above for Rx2 :)
2 new convenience methods were added to accomplish this very thing.
toSingle()
converts an Observable that emits a single item into a Single that emits that item
toObservable
converts a Single into an Observable that emits the item emitted by the Single and then completes
(source: http://reactivex.io/documentation/single.html)
In rxjava2 you can use Single.fromObservable()
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