### Question:
MentionsApplicationReadyEventListener extends AbstractEventListener implements Initializable { @Override public void onEvent(Event event, Object source, Object data) { this.eventExecutor.startThreads(); } MentionsApplicationReadyEventListener(); @Override void onEvent(Event event, Object source, Object data); @Override void initialize();  }### Answer:
@Test void onEvent() { this.eventListener.onEvent(null, null, null); verify(this.eventExecutor).startThreads(); }