@Before
  public void setUp() throws Exception {
    EventBus eventBus = new SimpleEventBus();
    eventHandler = new EventCollectingAppRegistryEventHandler();
    eventBus.addHandler(AppRegistryEvent.class, eventHandler);

    appDescriptorRegistry = new AppDescriptorRegistry(eventBus);

    TypeMappingImpl typeMapping = new TypeMappingImpl();
    Node2BeanTransformerImpl transformer =
        new Node2BeanTransformerImpl(new PreConfiguredBeanUtils());
    ComponentsTestUtil.setInstance(
        Node2BeanProcessor.class, new Node2BeanProcessorImpl(typeMapping, transformer));
    ComponentsTestUtil.setImplementation(AppDescriptor.class, ConfiguredAppDescriptor.class);
  }
 @After
 public void tearDown() throws Exception {
   ComponentsTestUtil.clear();
 }