code: public static String getIdentifyerFromDN(String dn) {
  		if (dn != null) {
  			String[] parts = dn.trim().split(",");
  			String[] kvs;
  			if(parts.length > 0 && parts[0].contains("="))  {
  				kvs = parts[0].trim().split("=");
  				return kvs.length > 0 ? kvs[0] : null;
  			}
  		}
  		return null;
  	}
docs: Return the Value of the given Identifyer from a given dn.
  @param dn of the entry.
  @return the identifyer.