* guaranteed to be either exact or one less than the correct value. This follows from fact that
     * floor(floor(x)/i) == floor(x/i) for any real x and integer i != 0. The proof is not quite
     * trivial.
     */
    long quotient = ((dividend >>> 1) / divisor) << 1;
    long rem = dividend - quotient * divisor;
    return quotient + (compare(rem, divisor) >= 0 ? 1 : 0);
  }

   * MD5 (128 hash bits) hash function and the given secret key.
   *
   * <p>If you are designing a new system that needs HMAC, prefer {@link #hmacSha256} or other
   * future-proof algorithms <a
   * href="https://datatracker.ietf.org/doc/html/rfc6151#section-2.3">over {@code hmacMd5}</a>.
   *
   * @param key the secret key

        Wrapper<?> that = (Wrapper<?>) obj; // note: not necessarily a Wrapper<T>

        if (this.equivalence.equals(that.equivalence)) {
          /*
           * We'll accept that as sufficient "proof" that either equivalence should be able to
           * handle either reference, so it's safe to circumvent compile-time type checking.
           */
          @SuppressWarnings("unchecked")