* @throws IllegalArgumentException if the given key is inappropriate for initializing this MAC
   * @since 20.0
   */
  public static HashFunction hmacSha512(Key key) {
    return new MacHashFunction("HmacSHA512", key, hmacToString("hmacSha512", key));
  }

  /**
   * Returns a hash function implementing the Message Authentication Code (MAC) algorithm, using the