docs: public static byte[] convertHexStringToBytes(String hex)
      {
          if (hex.length() % 2 != 0)
          {
              throw new IllegalArgumentException("Hex string must have even number of characters.");
          }
          byte[] seed = new byte[hex.length() / 2];
          for (int i = 0; i < seed.length; i++)
          {
              int index = i * 2;
              seed[i] = (byte) Integer.parseInt(hex.substring(index, index + 2), 16);
          }
          return seed;
      }