docs: private static void pctEncode(byte data, ByteArrayOutputStream bos) {
      bos.write('%');
      char hex1 = Character.toUpperCase(Character.forDigit((data >> 4) & 0xF, 16));
      char hex2 = Character.toUpperCase(Character.forDigit(data & 0xF, 16));
      bos.write(hex1);
      bos.write(hex2);
    }