public void testAddAndRemoveHandlers() {
CountingEventBus eventBus = new CountingEventBus(new SimpleEventBus());
FooEvent.register(eventBus, fooHandler1);
FooEvent.register(eventBus, fooHandler2);
HandlerRegistration reg1 = FooEvent.register(eventBus, adaptor1);
eventBus.fireEvent(new FooEvent());
assertEquals(3, eventBus.getCount(FooEvent.TYPE));
assertFired(fooHandler1, fooHandler2, adaptor1);
FooEvent.register(eventBus, fooHandler3);
assertEquals(4, eventBus.getCount(FooEvent.TYPE));