Yeah. I'm trying to align the metadata in two different repositories. This property is split in the other repo. (Singleton value property and then multivariate property if more than one value is needed.) I wanted to see how much work this was going to be.
Yes, you can do it in the Java API as that is how we implement the public API - but again only on 5.2.1.
In general the public API is cleaner. The Java API has a couple of oddities for things like multi-select facets - but these do not matter for this case. They were a pain to do in a backwards compatible way with the Java API.