@Override
    public void init(ServletConfig config) throws ServletException {
        ServletContext sc = config.getServletContext();
        String log4jLocation = config.getInitParameter("log4j-properties-location");
        File propFile = new File(sc.getRealPath("/") + log4jLocation);
        if (propFile.exists()) {
            PropertyConfigurator.configure(sc.getRealPath("/") + log4jLocation);
            LOGGER.info("Initializing log4j.");
        } else {
            throw new RuntimeException("Init log4j-properties-file not found");
        }
        super.init(config);
    }