I had a look at the protocol specification (that PDF download mentioned in the page you linked to). Somewhere not far from the beginning it says:
SData is a REST-style web services protocol.
Which suggests to me that you need a REST web-service client written in Java. The one which I've heard of is called Jersey, but you might find others with some web searching.
But it seems that you've been accessing the database via SQL up to now? In that case it would be a rewrite to access it via web services, which is what they seem to want you to do.
Hope that's more helpful than it looks to me...