@Before
public void before() {
db = new Fongo("test").getDB("test");
FakeAggregateWithSubclassMapping mapping = new FakeAggregateWithSubclassMapping();
session = new MongoSessionImpl(db, new CriteriaFactory());
MapperContext context = new MapperContext();
mapping.buildMapper(context);
session.setMappingContext(context);
session.start();
}