文件上传

Servlet SpringMVC实现文件上传

Servlet

a、jar包 ：Commons-fileUpload.jar Commons-io.jar

b、配置 在form表单里要配置一个属性 enctype = “multipart/form-data”

<form action="uploadServlet" method="post" enctype="multipart/form-data">
    学号：<input type="text" name="sno"/> <br>
    姓名：<input type="text" name="sname"/> <br>
    上传文件：<input type="file" name="spicture"/> <br>
    <input type="submit" value="提交">
</form>

c、实现：新建Servlet

//处理编码
request.setCharacterEncoding("utf-8");
response.setContentType("text/html;charset=UTF-8");
response.setCharacterEncoding("utf-8");
//
boolean isMultipart = ServletFileUpload.isMultipartContent(request);
try {
    if (isMultipart) {  //判断前台form表单是否有multiparty 属性
        FileItemFactory factory = new DiskFileItemFactory();
        ServletFileUpload upload = new ServletFileUpload(factory);

        List<FileItem> items = upload.parseRequest(request);
        Iterator<FileItem> iter = items.iterator();
        while(iter.hasNext()){
            FileItem item = iter.next();
            String fieldName = item.getFieldName();
            if(item.isFormField()) {
                int sno = -1;
                String sname = null;
                if (fieldName.equals("sno")) {
                    sno = Integer.parseInt(item.getString("utf-8"));
                } else if (fieldName.equals("sname")) {
                    sname = item.getString("utf-8");
                } else {
                    System.out.println("其他字段....");
                }
            }else{
                //上传      //获取文件名
                String fileName = item.getName();
                //获取文件内容          //定义上传文件路径
                String path = "E:\upload";
                File file = new File(path,fileName);
                item.write(file);
                System.out.println("文件上传成功"+fileName);
                return;
            }
        }
    }
    } catch (FileUploadException e) {
        e.printStackTrace();
    } catch (Exception e) {
        e.printStackTrace();
    }
}

SpringMVC 实现文件上传

和servlet基本一样，都是通过 commons-io.jar和 commons.fileUpload.jar springmvc可以简化代码

• jar包 commons-io.jar和commons - FileUpload.jar

• 配置 实现一个接口 CommonsMultipartResolver

<!-- 配置CommonsMultipartReslover,用于实现文件上传 将其加入IOC容器 
 springioc容器在初始化的时候  会自动寻找一个 id="multipartResolver"的bean，并将其将加入IOC容器
 -->	
<bean id="multipartResolver" 
                         class="org.springframework.web.multipart.commons.CommonsMultipartResolver">
    <property name="defaultEncoding" value="UTF-8"></property>
    <!-- 上传单个文件最大值  单位是byte -->
    <property name="maxUploadSize" value="102400000"></property>
</bean>

• index.jsp

<form action="handler/testUpload" method="post" enctype="multipart/form-data">
    <input type="file" name="file">
    描述<input type="text" name="desc" >	
    <input type="submit" value="提交">		
</form>

• 服务端

  @RequestMapping(value = "testUpload")
public String testUpload(@RequestParam("desc") String desc,@RequestParam("file")  MultipartFile file) throws IOException {
  
      System.out.println("文件描述信息："+file);	
      InputStream input = file.getInputStream();   //IO
      //上传什么名字保存什么名字
      String fileName = file.getOriginalFilename();
      OutputStream output = new FileOutputStream("d:\"+fileName);
  
      byte[] bs = new byte[100];
      int len = -1;
      while( (len = input.read(bs))!=-1) {
          output.write(bs, 0, len);
      }
      output.close();
      input.close();
      //将file上传到服务器中的某一个硬盘文件中
      System.out.println("上传成功");
      return "success";
   }