code: public void contextDestroyed(ServletContextEvent arg0) {
  		Iterator<Driver> drivers = DriverManager.getDrivers();
  		while (drivers.hasNext()) {
  			Driver driver = drivers.next();
  			DriverManager.deregisterDriver(driver);
  			DriverImpl impl = (DriverImpl) driver;
  			impl.shutdown();
  		}
  	}
docs: /*
  (non-Javadoc)
  
  @see javax.servlet.ServletContextListener#contextDestroyed(javax.servlet.ServletContextEvent)