The GPS device offers an index method that will run a very generic HQL query (from EntityName) to grab all the searchable entities from the underlying datastore and place them into the Lucene index. However, for large databases, this can be very problematic or even unnecessary. A nice feature, which apparently the JPA device supports, is to define custom HQL queries that will limit the results for certain entities/classnames. Also see CMP-213 for similar work.