root.pred = this;
    void access()    {      if (accessOrder && succ != null)        {          modCount++;          if (this == root)            {              root = succ;              pred.succ = this;              succ = null;            }          else            {              pred.succ = succ;              succ.pred = pred;              succ = null;              pred = root.pred;              pred.succ = this;            }        }    }