### Question:
CallbackRegistration { public C delegate() { return delegate; } @SuppressWarnings("unchecked")  CallbackRegistration(Class<C> type); C delegate(); ListenerRegistration register(C callback);  }### Answer:
@Test public void testEmpty() { uut.delegate().noargs(); uut.delegate().someargs("test", true); assertNotNull(uut.delegate().toString()); assertTrue(uut.delegate().equals(uut.delegate())); }