Emmanuel mentioned in his previous Search post the new Statistics interface which is new in Hibernate search 3.3 (latest version 3.3.0.Beta1). I thought it is time to write a little bit more about it. The API is actually self-explanatory:
While working on Hibernate Search 3.3, we have discovered a critical issue with Hibernate 3.2. If you use Hibernate Core 3.5 in a JTA environment (recommended), the way Hibernate Search 3.2 registers itself can lead to inconsistent indexing and generate assertion failures.
All this is fixed in Hibernate 3.2.1 which you can get here and ported to trunk as well. We have also added tests to cover the JTA area.
One of the points for using Hibernate Search is that your valued business data is stored in the database: a reliable transactional and relational store.
So while Hibernate Search keeps the index in sync with the database during regular use, in several occasions you'll need to be able to rebuild the indexes from scratch: