### Question:
RegistryMgtUIActivitiesServiceComponent { protected void unsetRegistryService(RegistryService registryService) { CommonUtil.setRegistryService(null); }    }### Answer:
@Test public void unsetRegistryService() throws Exception { RegistryService service = mock(RegistryService.class); RegistryMgtUIActivitiesServiceComponent component = new RegistryMgtUIActivitiesServiceComponent(); component.unsetRegistryService(service); assertNull(CommonUtil.getRegistryService()); }