### Question:
HeroModelPersisterAutoCollector { public Collection<HeroModelPersister> collect() { return objectFactory.instantiateAllImplementers(HeroModelPersister.class); } HeroModelPersisterAutoCollector(ObjectFactory objectFactory); Collection<HeroModelPersister> collect();  }### Answer:
@Test public void forwardsImplementorInstantiationsToObjectFactory() { HeroModelPersister expectation = mock(HeroModelPersister.class); factory.add(HeroModelPersister.class, expectation); Collection<HeroModelPersister> actualResult = collector.collect(); assertThat(actualResult, hasItem(expectation)); }