}

    @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;
    }
  }

  /**

 * defined as the <i>least</i> element in the queue according to the queue's comparator. But unlike
 * a regular priority queue, the methods {@link #peekLast}, {@link #pollLast} and {@link
 * #removeLast} are also provided, to act on the <i>greatest</i> element in the queue instead.
 *
 * <p>A min-max priority queue can be configured with a maximum size. If so, each time the size of

        }
    }

    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) {

    }

    /**
     * Disposes of all registered resources.
     */
    public static synchronized void dispose() {
        while (!disposables.isEmpty()) {
            final Disposable disposable = disposables.removeLast();
            try {
                disposable.dispose();
            } catch (final Throwable t) {

            } 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
    }

                cycle.addLast(v.label);
                List<String> ret = visitCycle(v.children, stateMap, cycle);
                if (ret != null) {
                    return ret;
                }
                cycle.removeLast();
                stateMap.put(v, DfsState.VISITED);
            } else if (state == DfsState.VISITING) {
                // we are already visiting this vertex, this mean we have a cycle

                    List<String> ret = visitCycle(graph, graph.get(v), stateMap, cycle);
                    if (ret != null) {
                        return ret;
                    }
                    cycle.removeLast();
                    stateMap.put(v, DfsState.VISITED);
                } else if (state == DfsState.VISITING) {
                    // we are already visiting this vertex, this mean we have a cycle

        // In this case, we simply put the elements into these buckets evenly.
        return list.chunked(list.size / expectedBucketNumber, smallElementAggregateFunction)
    }

    val largestElement = list.removeFirst()!!

    val largestElementSize = toIntFunction(largestElement)

    if (largestElementSize >= roughSizeOfEachBucket) {
        var bucketNumberOfFirstElement =
            determineBucketNumberForLargeElment(

    }

  override fun isCanceled() = canceled

  override fun plan(): FakePlan {
    // Return deferred plans preferentially. These don't require addPlan().
    if (deferredPlans.isNotEmpty()) return deferredPlans.removeFirst() as FakePlan

    if (nextPlanIndex >= plans.size && autoGeneratePlans) addPlan()

    require(nextPlanIndex < plans.size) {
      "not enough plans! call addPlan() or set autoGeneratePlans=true in the test to set this up"