    @Test
    public void testBadAddNotificationCenterListener() {

        OptimizelyClient optimizelyClient = new OptimizelyClient(optimizely, logger);
        ActivateNotificationListener listener = new ActivateNotificationListener() {
            @Override
            public void onActivate(Experiment experiment, String userId, Map<String, ?> attributes, Variation variation, LogEvent event) {

            }
        };
        optimizelyClient.getNotificationCenter().addNotificationListener(NotificationCenter.NotificationType.Activate, listener);
        verify(optimizely.notificationCenter).addNotificationListener(NotificationCenter.NotificationType.Activate, listener);
    }