ObjectQueue implements Iterable<T>, Closeable { public abstract int size();  static ObjectQueue<T> create(QueueFile qf, Converter<T> converter); static ObjectQueue<T> createInMemory(); abstract @Nullable QueueFile file(); abstract int size(); boolean isEmpty(); abstract void add(T entry); abstract @Nullable T peek(); List<T> peek(int max); List<T> asList(); void remove(); abstract void remove(int n); void clear();  }
@Test public void size() throws IOException { assertThat(queue.size()).isEqualTo(3); }