### Question:
EventManager implements IEventManager { public boolean hasEventHandler(Class eventHandlerClass) { Optional<IEventHandler> eventHandler = getEventHandlers().stream().filter(h -> h.getClass().getName().equalsIgnoreCase(eventHandlerClass.getName())).findFirst(); return eventHandler.isPresent(); } EventManager(); void registerEventHandler(IEventHandler eventHandler); void autoDiscovery(); void publish(Object event); boolean hasEventHandler(Class eventHandlerClass); E getEventHandler(Class<E> eventHandlerClass); IDisposable onEvent(Class<E> eventClass, Consumer<E> consumer); void setDefaultEventHandler(Class eventHandler); void setDefaultEventHandler(String eventHandler); void close();  }### Answer:
@Test public void testHasEventHandlerByClass() { Assertions.assertTrue(eventManager.hasEventHandler(SimpleEventHandler.class), "should fine a eventHandler for class SimpleEventHandler"); }