@SuppressWarnings("unchecked")
    @CheckReturnValue
    @SchedulerSupport(SchedulerSupport.NONE)
    public final Observable<T> startWithArray(T... items) {
        Observable<T> fromArray = fromArray(items);
        if (fromArray == empty()) {
            return RxJavaPlugins.onAssembly(this);
        }
        return concatArray(fromArray, this);
    }