spring mvc在普通类中获取HttpServletRequest对象

如题，需要在web.xml中配置request监听，如下

    <listener>
        <description>spring request监听器</description>
        <listener-class>org.springframework.web.context.request.RequestContextListener</listener-class>
     </listener>

在普通的类中使用如下

HttpServletRequest request = ((ServletRequestAttributes) RequestContextHolder.getRequestAttributes())
                    .getRequest();