How do you query object collections in Java (Criteria/SQL-like)?

Question

Suppose you have a collection of a few hundred in-memory objects and you need to query this List to return objects matching some SQL or Criteria like query. For example, you

Answer 1

If you need a single concrete match, you can have the class implement Comparator, then create a standalone object with all the hashed fields included and use it to return the index of the match. When you want to find more than one (potentially) object in the collection, you'll have to turn to a library like JoSQL (which has worked well in the trivial cases I've used it for).

In general, I tend to embed Derby into even my small applications, use Hibernate annotations to define my model classes and let Hibernate deal with caching schemes to keep everything fast.