struts2下传文件删除struts.multipart.saveDir上的临时文件

<filter>???
??????????????? <filter-name>struts-cleanup</filter-name>???
??????????????? <filter-class>org.apache.struts2.dispatcher.ActionContextCleanUp</filter-class>???
??????? </filter>?
??????? <filter-mapping>?
??????????????? <filter-name>struts-cleanup</filter-name>?
??????????????? <url-pattern>*.action</url-pattern>?
??????? </filter-mapping>