spring mvc在普通類中獲取HttpServletRequest對象

如題，需要在web.xml中配置request監聽，如下

    <listener>
        <description>spring request監聽器</description>
        <listener-class>org.springframework.web.context.request.RequestContextListener</listener-class>
     </listener>

在普通的類中使用如下

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