<listener>
        <listener- class >org.web.util.ApplicationStartupListener</listener- class >
    </listener>

    
...
 public   void  contextInitialized(ServletContextEvent servletContextEvent) {
         try  {
            ServletContext sc = servletContextEvent.getServletContext();

            String dataRootPath = sc.getInitParameter("datapath");

             if  (dataRootPath ==  null ) {
                 throw   new  IllegalArgumentException("datapath parameter is missing");
            }

            String dbListFileName = sc.getInitParameter("db_list");

             if  (dbListFileName ==  null ) {
                 throw   new  IllegalArgumentException("db_list parameter is missing.");
            }

            WebDbListManager webDbListManager =  new  WebDbListManager();
            webDbListManager.load(dataRootPath + dbListFileName);

            sc.setAttribute(DB_LIST_BEAN, webDbListManager);
            sc.setAttribute(DATA_ROOT_PATH, dataRootPath);
        }
         catch  (DocumentException e) {
            servletContextEvent.getServletContext().log("Can not load database list file", e);
        }
    }
...