在用springmvc+mybatis进行项目开发时，上传文件抛异常..
org.springframework.beans.BeanInstantiationException: Could not instantiate bean class [org.springframework.web.multipart.MultipartFile]: Specified class is an interface org.springframework.beans.BeanUtils.instantiateClass(BeanUtils.java:101) org.springframework.web.bind.annotation.support.HandlerMethodInvoker.resolveModelAttribute(HandlerMethodInvoker.java:762) org.springframework.web.bind.annotation.support.HandlerMethodInvoker.resolveHandlerArguments(HandlerMethodInvoker.java:356) org.springframework.web.bind.annotation.support.HandlerMethodInvoker.invokeHandlerMethod(HandlerMethodInvoker.java:171) org.springframework.web.servlet.mvc.annotation.AnnotationMethodHandlerAdapter.invokeHandlerMethod(AnnotationMethodHandlerAdapter.java:426) org.springframework.web.servlet.mvc.annotation.AnnotationMethodHandlerAdapter.handle(AnnotationMethodHandlerAdapter.java:414) org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:790) org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:719) org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:644) org.springframework.web.servlet.FrameworkServlet.doPost(FrameworkServlet.java:560) javax.servlet.http.HttpServlet.service(HttpServlet.java:646) javax.servlet.http.HttpServlet.service(HttpServlet.java:727) org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52) org.springframework.web.filter.CharacterEncodingFilter.doFilterInternal(CharacterEncodingFilter.java:88) org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:76) org.springframework.orm.hibernate3.support.OpenSessionInViewFilter.doFilterInternal(OpenSessionInViewFilter.java:198) org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:76)
解决方法：在Controller的MultipartFile参数前面加上@RequestParam就行了！
如：
@RequestMapping("/save") public String save(User user, HttpServletResponse response, @RequestParam MultipartFile file_pic//接收图片 )throws Exception{ //原始名称 String originalFilename = file_pic.getOriginalFilename(); //上传图片 if(file_pic!=null && originalFilename!=null && originalFilename.length()>0){ //存储图片的物理路径 String pic_path = "G:\\nfsysuems\\temp\\"; //新的图片名称 String newFileName = UUID.randomUUID() + originalFilename.substring(originalFilename.lastIndexOf(".")); //新图片 File newFile = new File(pic_path+newFileName); //将内存中的数据写入磁盘 file_pic.transferTo(newFile); //新图片写入user user.setPic(newFileName); } .......