code: public String getMd5(String msg) {
  		MessageDigest md;
  		try {
  			md = getMessageDigest();
  			byte[] hash = md.digest(msg.getBytes(StandardCharsets.UTF_8));
  			//converting byte array to Hexadecimal String
  			StringBuilder sb = new StringBuilder(2 * hash.length);
  			for (byte b : hash) {
  				sb.append(String.format("%02x", b & 0xff));
  			}
  			return sb.toString();
  		} catch (NoSuchAlgorithmException ex) {
  			logger.error("Fail to get MD5 of String "+msg, ex);
  		}
  		return null;
  	}
docs: Create a md5 from string
  
  @param msg
  @return