public boolean equals(Object o) {
      if (o == this) return true;
      if (!(o instanceof FastFixedSet)) return false;

      int[] extdata = ((FastFixedSet<?>)o).getData();
      int[] intdata = data;

      for (int i = intdata.length - 1; i >= 0; i--) {
        if (intdata[i] != extdata[i]) {
          return false;
        }
      }

      return true;
    }
public boolean equals(Object o)