return delegate.offerLast(e);
    }

    @Override
    public E removeFirst() {
      assertTrue(Thread.holdsLock(mutex));
      return delegate.removeFirst();
    }

    @Override
    public E removeLast() {
      assertTrue(Thread.holdsLock(mutex));
      return delegate.removeLast();
    }

    @Override
    public @Nullable E pollFirst() {

    delegate().push(e);
  }

  @CanIgnoreReturnValue
  @Override
  @ParametricNullness
  public E removeFirst() {
    return delegate().removeFirst();
  }

  @CanIgnoreReturnValue
  @Override
  @ParametricNullness
  public E removeLast() {
    return delegate().removeLast();
  }

  @CanIgnoreReturnValue
  @Override
  public boolean removeFirstOccurrence(@CheckForNull Object o) {

        list.addLast("1");
        list.addLast("2");
        list.removeFirst();
        assertThat(list.getFirst(), is("2"));
    }

    /**
     * @throws Exception
     */
    @Test
    public void testRemoveLast() throws Exception {
        list.addLast("1");
        list.addLast("2");
        list.removeLast();
        assertThat(list.getLast(), is("1"));
    }

    /**

            if (elementStack.contains(element)) {
                while (!elementStack.getFirst().equals(element)) {
                    visitor.onEndHtmlElement(elementStack.removeFirst());
                }
                elementStack.removeFirst();
                visitor.onEndHtmlElement(element);
            }
        }

        private void unwindTo(Collection<String> ancestors, TokenVisitor visitor) {

  fun enqueueRequestCookies(vararg cookies: Cookie) {
    requestCookies.add(cookies.toList())
  }

  fun takeResponseCookies(): List<Cookie> {
    return responseCookies.removeFirst()
  }

  fun assertResponseCookies(vararg cookies: String?) {
    assertThat(takeResponseCookies().map(Cookie::toString)).containsExactly(*cookies)
  }

  override fun saveFromResponse(
    url: HttpUrl,

        }
    }

    public void push(Element element) {
        stack.getFirst().appendChild(element);
        stack.addFirst(element);
    }

    public Element pop() {
        Element element = stack.removeFirst();
        if (emptyPara(element)) {
            element.getParentNode().removeChild(element);
        }
        return element;
    }

    private boolean emptyPara(Element element) {

    }

    @Override
    public void start(String context) {
        contextStack.addFirst(context);
    }

    @Override
    public void finish() {
        contextStack.removeFirst();
    }

    }

    @Override
    public T next() {
      Iterator<T> itr = stack.getLast(); // throws NSEE if empty
      T result = checkNotNull(itr.next());
      if (!itr.hasNext()) {
        stack.removeLast();
      }
      Iterator<T> childItr = children(result).iterator();
      if (childItr.hasNext()) {
        stack.addLast(childItr);
      }
      return result;
    }
  }

  /**

    private final Deque<Runnable> tasks = Queues.newArrayDeque();

    @Override
    public void execute(Runnable task) {
      tasks.add(task);
    }

    private void runNext() {
      tasks.removeFirst().run();
    }
  }

  public void testAsyncReload() throws Exception {
    final AtomicInteger loadCount = new AtomicInteger();
    final AtomicInteger reloadCount = new AtomicInteger();

            } catch (Exception e) {
                throw new ClassDocGenerationException("Could not load the class documentation for class '$className'.", e)
            }
        } finally {
            currentlyBuilding.removeLast()
        }
    }

    private File getFileForClass(String className) {
        File classFile = new File(classDocbookDir, "${className}.xml")
        classFile
    }