I've authored a library based on the DB class, which will let you interact with RDBMS in the Java programming language.
There's nothing really novel going on; we just provide several concrete DB<A> implementations; five lines of glue for HikariCP; machinery to interpret DB instances as Validation, CompletableFuture, ListenableFuture, etc; a couple of convenience transforms such as unique() and sequence().
Hopefully everything is fairly canonical and we do not do any obviously unnatural / arbitrary things.
The major thing (work in progress) that we will hopefully achieve is provide end-user documentation which is exhaustive and does not assume any prior exposure to functionaljava or functional programming in general.
There are also notes of a draft talk on the topic here:
Contributions, especially critique, are very welcome. Contributor documentation is coming some time this week.
Lastly, if somebody likes it and finds it useful, I'll be grateful if you help me spread the word.
Cheers, Dimitar