docs: private int binaryFindDelete(
      int              lower,
      int              upper,
      Object           delKey)
    {
      java.util.Comparator comp = insertComparator();
      int xcc;                       /* Current compare result                */
      int i;
      int idx = -1;                  /* Returned index (-1 if not found)      */
      while (lower <= upper)         /* Until they cross                      */
      {
        i = (lower + upper) >>> 1;   /* Mid-point of current range            */
        xcc = comp.compare(delKey, _nodeKey[i]);
        if (xcc < 0)                 /* SEARCH_KEY < NODE_KEY                 */
          upper = i - 1;             /* Discard upper half of range           */
        else                         /* SEARCH_KEY >= NODE_KEY                */
          {
            if (xcc > 0)             /* SEARCH_KEY > NODE_KEY                 */
              lower = i + 1;         /* Discard lower half of range           */
            else                     /* SEARCH_KEY FOUND                      */
              {
                idx = i;             /* Remember the index                    */
                break;               /* We're done                            */
              }
          }
      }
      return idx;
    }