What if Java collections and Java hierarchies were easily searchable? They are with Boon! What if it were easy to query a complex set of Java objects at runtime? What if there were an API that kept your object indexes (really just TreeMaps, and HashMaps) in sync.? Well then you would have Boon's data repo. This article shows how to use Boon's data repo utilities to query Java objects. Boon comes with a simple criteria API that makes working with Java collections a snap.