* second invocation, so implementors have made various choices, including:
 *
 * <ul>
 *   <li>returning the same iterator again
 *   <li>throwing an exception of some kind
 *   <li>or the usual, <i>robust</i> behavior, which all known {@link Collection} implementations
 *       have, of returning a new, independent iterator
 * </ul>
 *

  abstract long fn(long currentValue, long newValue);

  /**
   * Handles cases of updates involving initialization, resizing, creating new Cells, and/or
   * contention. See above for explanation. This method suffers the usual non-modularity problems of
   * optimistic retry code, relying on rechecked sets of reads.
   *
   * @param x the value
   * @param hc the hash code holder
   * @param wasUncontended false if CAS failed before call

   * lists are sublist views of the original list, produced on demand using {@link List#subList(int,
   * int)}, and are subject to all the usual caveats about modification as explained in that API.
   *
   * @param list the list to return consecutive sublists of
   * @param size the desired size of each sublist (the last may be smaller)

    } catch (NoSuchElementException expected) {
    }

    try {
      iter.next();
      fail("next() should throw NoSuchElementException as usual");
    } catch (NoSuchElementException expected) {
    }

    try {
      iter.peek();
      fail("peek() should still throw NoSuchElementException after next()");
    } catch (NoSuchElementException expected) {

   * #expectContents(Object[]) expectContents(E...)} and other convenience methods. The creation of
   * multiple containers in a single method is discouraged in most cases, but it is vital to the
   * iterator tests.
   *
   * @return the new container instance
   * @param newValue the new container instance
   */
  @CanIgnoreReturnValue
  protected C resetContainer(C newValue) {

  abstract long fn(long currentValue, long newValue);

  /**
   * Handles cases of updates involving initialization, resizing, creating new Cells, and/or
   * contention. See above for explanation. This method suffers the usual non-modularity problems of
   * optimistic retry code, relying on rechecked sets of reads.
   *
   * @param x the value
   * @param hc the hash code holder
   * @param wasUncontended false if CAS failed before call

  /**
   * Drains the queue as {@linkplain #drain(BlockingQueue, Collection, int, long, TimeUnit)}, but
   * with a different behavior in case it is interrupted while waiting. In that case, the operation
   * will continue as usual, and in the end the thread's interruption status will be set (no {@code
   * InterruptedException} is thrown).
   *
   * @param q the blocking queue to be drained
   * @param buffer where to add the transferred elements

   * expect, but there are some subtleties. First, we do guarantee that, if the output future at
   * index n is done, the output future at index n-1 is also done. (But as usual with futures, some
   * listeners for future n may complete before some for future n-1.) However, it is possible, if
   * one input completes with result X and another later with result Y, for Y to come before X in

    } catch (NoSuchElementException expected) {
    }

    try {
      iter.next();
      fail("next() should throw NoSuchElementException as usual");
    } catch (NoSuchElementException expected) {
    }

    try {
      iter.peek();
      fail("peek() should still throw NoSuchElementException after next()");
    } catch (NoSuchElementException expected) {

   * #expectContents(Object[]) expectContents(E...)} and other convenience methods. The creation of
   * multiple containers in a single method is discouraged in most cases, but it is vital to the
   * iterator tests.
   *
   * @return the new container instance
   * @param newValue the new container instance
   */
  @CanIgnoreReturnValue
  protected C resetContainer(C newValue) {