@CheckReturnValue
    @NonNull
    public final ParallelFlowable<T> doOnNext(@NonNull Consumer<? super T> onNext, @NonNull ParallelFailureHandling errorHandler) {
        ObjectHelper.requireNonNull(onNext, "onNext is null");
        ObjectHelper.requireNonNull(errorHandler, "errorHandler is null");
        return RxJavaPlugins.onAssembly(new ParallelDoOnNextTry<T>(this, onNext, errorHandler));
    }