MultipartHttpServletRequest req =(MultipartHttpServletRequest)request;
MultipartFile multipartFile =  req.getFile("file");

这样写总是报

java.lang.ClassCastException: org.apache.catalina.connector.RequestFacade cannot be cast to org.springframework.web.multipart.MultipartHttpServletRequest

at com.yswh.controller.YsShowController.insert(YsShowController.java:63)

at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)

at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)

at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)

at java.lang.reflect.Method.invoke(Method.java:498)

at org.springframework.web.method.support.InvocableHandlerMethod.doInvoke(InvocableHandlerMethod.java:190)

at org.springframework.web.method.support.InvocableHandlerMethod.invokeForRequest(InvocableHandlerMethod.java:138)

at org.springframework.web.servlet.mvc.method.annotation.ServletInvocableHandlerMethod.invokeAndHandle(ServletInvocableHandlerMethod.java:104)

at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.invokeHandlerMethod(RequestMappingHandlerAdapter.java:892)

at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.handleInternal(RequestMappingHandlerAdapter.java:797)

at org.springframework.web.servlet.mvc.method.AbstractHandlerMethodAdapter.handle(AbstractHandlerMethodAdapter.java:87)

at org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:1039)

at org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:942)

at org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:1005)

at org.springframework.web.servlet.FrameworkServlet.doPost(FrameworkServlet.java:908)

at javax.servlet.http.HttpServlet.service(HttpServlet.java:660)

at org.springframework.web.servlet.FrameworkServlet.service(FrameworkServlet.java:882)

at javax.servlet.http.HttpServlet.service(HttpServlet.java:741)

该怎么解决？