SpringMVC 文件上传 消息 Required request part ‘file‘ is not present描述 由于被认为是客户端对错误（例如：畸形的请求语法、无效的请求信息帧或者

package com.zhr.springmvchelloworld;
import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestParam;
import org.springframework.web.multipart.MultipartFile;
import java.io.IOException;
@Controller
public class TestFileUpload {
    @RequestMapping("fileUpload")
    public String uploadFile(@RequestParam("file") MultipartFile file) throws IOException
    {
        System.out.println("file.getOriginalFilename() = " + file.getOriginalFilename());
        // 文件的接收参数 @RequestParam MultipartFile file 中的 file
        System.out.println("file.getName() = " + file.getName());
        // 文件的类型
        System.out.println("file.getContentType() = " + file.getContentType());
        System.out.println("file.getResource() = " + file.getResource());
        System.out.println("file.getBytes() = " + file.getBytes());
        // 文件大小
        System.out.println("file.getSize() = " + file.getSize());
        return "file";
    }
}

<form action="http://localhost:8080/springmvc_helloworld_war_exploded/fileUpload" method="post" enctype="multipart/form-data">
  <div><input type="file" multiple="multiple" accept="image/*" name="file" id="file"></div>
  <div><input type="submit" value="上传"></div>
</form>

<bean id="multipartResolver" class="org.springframework.web.multipart.commons.CommonsMultipartResolver">
        <property name="defaultEncoding" value="UTF-8"></property>
        <property name="maxUploadSize" value="10240000"></property>
</bean>