springmvc文件上传

pom依赖


<dependency>
      <groupId>commons-fileupload</groupId>
      <artifactId>commons-fileupload</artifactId>
      <version>1.3.3</version>
</dependency>

springmvc.xml

<bean id="multipartResolver" class="org.springframework.web.multipart.commons.CommonsMultipartResolver">
        <!-- 必须和用户JSP 的pageEncoding属性一致，以便正确解析表单的内容 -->
        <property name="defaultEncoding" value="UTF-8"></property>
        <!-- 文件最大大小(字节) 1024*1024*50=50M-->
        <property name="maxUploadSize" value="52428800"></property>
        <!--resolveLazily属性启用是为了推迟文件解析，以便捕获文件大小异常-->
        <property name="resolveLazily" value="true"/>
</bean>

upload.jsp


<form action="${pageContext.request.contextPath}/book/upload" method="post" enctype="multipart/form-data">
    请选择文件:<input type="file" name="xxx">
    <input type="submit" value="ok">
</form>

import org.apache.commons.io.FileUtils;

XXXControl


@RequestMapping("/upload")
    public String upload(HttpServletRequest req, MultipartFile xxx){
        String fileName=xxx.getOriginalFilename();
        String contentType=xxx.getContentType();
        try {
              FileUtils.copyInputStreamToFile(myfile.getInputStream(),new File("E:/images/"+fileName));
        } catch (IOException e) {
            e.printStackTrace();
        }
        return "redirect:/book/list";
    }

注意：
upload.jsp的xxx一定名字一致！！！(我取得是myfile)
XXXControl里的xxx
在这里插入图片描述

配置一下图片的虚拟映射：

在这里插入图片描述
成功！

json支持

XXXControl

@ResponseBody
    @RequestMapping("/json1")
    public Map json1(HttpServletRequest req) {
        Map map = new HashMap();
        PageBean pageBean = new PageBean();
        pageBean.setRequest(req);
        Book book = new Book();
        book.setBname("");
        List<Map> list = bookService.listPager1(book, pageBean);
        map.put("total", pageBean.getTotal());
        map.put("data", list);


        return map;
    }

    @ResponseBody
    @RequestMapping("/json2")
    public List<Map> json2(HttpServletRequest req) {
        PageBean pageBean = new PageBean();
        pageBean.setRequest(req);
        Book book = new Book();
        book.setBname("");
        List<Map> list = bookService.listPager1(book, pageBean);


        return list;
    }

    @RequestMapping("/json3")
    public String json3() {
        return "springmvc string to json";
    }

第一种返回：Map
在这里插入图片描述

第二种返回：List< Map>

第三种返回：String