It slices! It dices! But wait, there's more...
Ginsu provides lightweight data warehousing for Java programmers.
You describe a data warehouse with a small bit of code and ginsu builds it for you: tables, views, indexes, surrogate keys, the works. Then you write some ETL code to populate the warehouse via a simple key-value interface.
Support is currently provided for the h2 database but the persistence layer is completely pluggable.