code: private static boolean checkIpv4(byte[] bytes, int pos, int length) {
  		int start = pos;
  		for (int i = pos; i < length; i++) {
  			// assume at least one more symbol is present after dot
  			if (i == length - 1 && bytes[i] == '.') {
  				return false;
  			}
  			if (bytes[i] == '.' || i == length - 1) {
  				int v;
  				if (i - start == 0 && i != length - 1) {
  					return false;
  				}
  				try {
  					v = trimAndDecodePositiveInt(bytes, start, i - start);
  				} catch (ParseException e) {
  					return false;
  				}
  				if (v < 0 || v > 255) return false;
  				start = i + 1;
  			}
  		}
  		return true;
  	}
docs: /*
  Checks only dot decimal format(192.168.0.208 for example)
  more -> https://en.wikipedia.org/wiki/IPv4