I am focusing on a JVM client for any remote MySQL server and want to offer an "offline" capacity.

I believed of utilizing a "100%" java file-based DB which in fact had excellent Hibernate support. Also (when the order isn't too tall), I must keep my MySQL schema changes low.

An amount you advise?

Thank you for the help!

Try http://www.h2database.com . - small - good hibernate support - file based - in memory option

Oozie (an Apache work for matching Hadoop jobs) uses Apache Derby.

Additionally to h2, and Derby pointed out by other solutions you may also use HSQLDB

Relating to your schema request h2 has numerous compatibility modes that could allow you to port your schema and queries unchanged.