docs: public static byte[] decodeChecked(String input) throws AddressFormatException {
          byte[] decoded  = decode(input);
          if (decoded.length < 4)
              throw new AddressFormatException.InvalidDataLength("Input too short: " + decoded.length);
          byte[] data = Arrays.copyOfRange(decoded, 0, decoded.length - 4);
          byte[] checksum = Arrays.copyOfRange(decoded, decoded.length - 4, decoded.length);
          byte[] actualChecksum = Arrays.copyOfRange(Sha256Hash.hashTwice(data), 0, 4);
          if (!Arrays.equals(checksum, actualChecksum))
              throw new AddressFormatException.InvalidChecksum();
          return data;
      }