@Test
public void testCreateObjectStore() throws Exception {

    HashSet<Car> backingCollection = new HashSet<Car>();
    WrappingPersistence<Car, Integer> wrappingPersistence =
            WrappingPersistence.aroundCollectionOnPrimaryKey(backingCollection, Car.CAR_ID);
    ObjectStore<Car> objectStore = wrappingPersistence.createObjectStore();
    assertTrue(objectStore instanceof CollectionWrappingObjectStore);
    assertEquals(backingCollection, ((CollectionWrappingObjectStore)objectStore).getBackingCollection());
}