### Question:
ObservableDeque extends ObservableListBase<E> implements Deque<E> { @Override public void clear() { if (hasListeners()) { beginChange(); nextRemove(0, this); } deque.clear(); ++modCount; if (hasListeners()) { endChange(); } } ObservableDeque(final Deque<E> deque); @Override void clear(); @Override boolean offer(final E e); @Override boolean add(final E e); @Override E remove(); @Override E poll(); @Override E element(); @Override E peek(); @Override E get(final int index); @Override int size(); @Override void addFirst(final E e); @Override void addLast(final E e); @Override boolean offerFirst(final E e); @Override boolean offerLast(final E e); @Override E removeFirst(); @Override E removeLast(); @Override E pollFirst(); @Override E pollLast(); @Override E getFirst(); @Override E getLast(); @Override E peekFirst(); @Override E peekLast(); @Override boolean removeFirstOccurrence(final Object o); @Override boolean removeLastOccurrence(final Object o); @Override void push(final E e); @Override E pop(); @Override Iterator<E> descendingIterator();  }### Answer:
@Test public void testClear() { assertEquals(deque.size(), 3); deque.clear(); mlo.check1AddRemove(deque, Arrays.asList(Integer.valueOf(1), Integer.valueOf(1), Integer.valueOf(3)), 0, 0); assertEquals(deque.size(), 0); }