I have seen some discussions in this forum about JDO query language.
One disadvatage with JDO-QL is that the filter is a text string and
not a java object. I am working with a open source project,
http://butler.sourceforge.net, and we have a powerful, but still very
simple, java API for defining queries (and a lot more) as java
objects. The query definition are later used for producing a SQL
select statement.

If you are tiered on working with low level JDBC calls, but still want
the power of SQL queries, you really should look at
bulter.sourceforge.net.

Best regards,
Fredrik