Just seconds ago we've released version 3.0 of MetaModel. MetaModel is an extensive library dedicated to unifying the world of datastores and making you productive in building data-centric applications.
With MetaModel you'll have a data-centric API for exploring, querying and (as of version 3.0) also updating this data. Databases and data formats range from relational (JDBC) databases, CSV files, Excel spreadsheets, MongoDB and CouchDB databases and a lot more! The unique feature of MetaModel is that you're offered the exact same API for all of these data formats, so you can write truly cross-datastore code which will allow your applications to work on a multitude of environments.
Furthermore, the API of MetaModel is extremely fluent and easy to learn, since it resembles SQL very much, but is type safe and checked at the same time. Think of it as a variant of LINQ for Java.
With version 3.0 we've added support for all CRUD operations, as well as added support for CouchDB and plain Java objects in Java collections as backend stores. Head on over to the MetaModel website for more information.