### Question:
DefaultMentionsEventExecutor implements MentionsEventExecutor, Initializable, Disposable { @Override public long getQueueSize() { return this.queue.size(); }  @Override void initialize(); @Override void startThreads(); @Override void dispose(); @Override void execute(DocumentReference documentReference, DocumentReference authorReference, String version); @Override long getQueueSize(); List<MentionsConsumer> getConsumers();  }### Answer:
@Test void getQueueSize() { this.executor.getQueueSize(); verify(this.blockingQueue).size(); }