MultipartFile对象为什么是空啊？

Question

mvc.xml:

    <bean id="multipartResolver" class="org.springframework.web.multipart.commons.CommonsMultipartResolver">
            <property name="defaultEncoding" value="UTF-8"/>
    </bean>

jsp：

名称：<input name="username" type="text" />
文件：<input type="file" name="uploadFile" />
<input value="提交" type="submit" />

Controller
@Controller
@RequestMapping("/user")
public class UserController {

@RequestMapping(value = "quick14")
@ResponseBody  //不进行跳转，直接进行数据响应
public void save14(String username, MultipartFile uploadFile) throws IOException {;
    System.out.println(username);
    System.out.println(uploadFile);
}

}

Answer 1

jsp:不知道为啥变了，下面补充，希望有大佬解答

<form method="post" action="${pageContext.request.contextPath}/user/quick14">
    名称：<input type="text" name="username"><br/>
    文件：<input type="file" name="uploadFile"><br/>
    <input type="submit" value="提交">
</form>