public Mongo createURL(String URL, int port) throws UnknownHostException
    {
    	try
    	{
    		mongo = new Mongo(URL, port);
    		logger.info("URL valide.");
    	}
    	catch (UnknownHostException e) {
    		logger.error("URL inexistante !");
    		throw e;
    	}
    	return mongo;
    }