code: private int findGreater(
      SearchComparator  comp,
      int               lower,
      int               upper,
      Object            searchKey)
    {
      int nkeys = numKeys(lower, upper);
      int idx = -1;
      if (nkeys < 4)
        idx = sequentialSearchGreater(comp, lower, upper, searchKey);
      else
        idx = binarySearchGreater(comp, lower, upper, searchKey);
      return idx;
    }
docs: Find an index entry that is either greater than or greater
  than or equal to the supplied key.
  
  @param searchKey The key to find.
  
  @return Index of key within node.  -1 if key does not exist.