@Override
    protected void implCloseChannel() {
      throw new RuntimeException("I bet you didn't think Thread.interrupt could throw");
    }

    void doBegin() {
      super.begin();
    }
  }

  /**
   * Because Thread.interrupt() can invoke arbitrary code, it can be slow (e.g. perform IO). To
   * protect ourselves from that we want to make sure that tasks don't spin too much waiting for the

    }
  }

  /**
   * Removes a number of occurrences of the specified element from this multiset. If the multiset
   * contains fewer than this number of occurrences to begin with, all occurrences will be removed.
   *
   * @param element the element whose occurrences should be removed
   * @param occurrences the number of occurrences of the element to remove

        // has now been moved after index.
        return new MoveDesc<>(actualLastElement, changes.replaced);
      }
    }
    // Trickled element was after index to begin with, no adjustment needed.
    return changes;
  }

  @CheckForNull
  private MoveDesc<E> fillHole(int index, E toTrickle) {
    Heap heap = heapForIndex(index);

    return getInet4Address(Arrays.copyOfRange(ip.getAddress(), 12, 16));
  }

  /**
   * Evaluates whether the argument is a 6to4 address.
   *
   * <p>6to4 addresses begin with the {@code "2002::/16"} prefix. The next 32 bits are the IPv4
   * address of the host to which IPv6-in-IPv4 tunneled packets should be routed.
   *
   * <p>For more on 6to4 addresses see section 2 of <a target="_parent"

   *
   * <p>If a task is {@linkplain Thread#interrupt interrupted} while a task is running:
   *
   * <ol>
   *   <li>execution will not stop until the task queue is empty.
   *   <li>tasks will begin execution with the thread marked as not interrupted - any interruption
   *       applies only to the task that was running at the point of interruption.

    return getInet4Address(Arrays.copyOfRange(ip.getAddress(), 12, 16));
  }

  /**
   * Evaluates whether the argument is a 6to4 address.
   *
   * <p>6to4 addresses begin with the {@code "2002::/16"} prefix. The next 32 bits are the IPv4
   * address of the host to which IPv6-in-IPv4 tunneled packets should be routed.
   *
   * <p>For more on 6to4 addresses see section 2 of <a target="_parent"

        // has now been moved after index.
        return new MoveDesc<>(actualLastElement, changes.replaced);
      }
    }
    // Trickled element was after index to begin with, no adjustment needed.
    return changes;
  }

  @CheckForNull
  private MoveDesc<E> fillHole(int index, E toTrickle) {
    Heap heap = heapForIndex(index);

 * <h4>Automatically closing</h4>
 *
 * You can extract a {@link Future} that represents the result of the last step in the pipeline by
 * calling {@link #finishToFuture()}. All objects the pipeline has captured for closing will begin
 * to be closed asynchronously <b>after</b> the returned {@code Future} is done: the future
 * completes before closing starts, rather than once it has finished.
 *
 * <pre>{@code
 * FluentFuture<UserName> userName =