Method fromFuture

src/main/java/io/reactivex/rxjava3/core/Single.java:1019–1024

Converts a Future into a Single and awaits its outcome in a blocking fashion. The operator calls Future#get(), which is a blocking me

(@NonNull Future<? extends T> future)

     * @see #fromCompletionStage(CompletionStage)
     */
    @CheckReturnValue
    @SchedulerSupport(SchedulerSupport.NONE)
    @NonNull
    public static <@NonNull T> Single<T> fromFuture(@NonNull Future<? extends T> future) {
        return toSingle(Flowable.fromFuture(future));
    }

    /**
     * Converts a {@link Future} into a {@code Single} and awaits its outcome, or timeout, in a blocking fashion.