SpringMVC - 11.SpringMVC(文件上传) - 《Java笔记》

文件上传/下载
依赖于Apache提供的两个jar
commons-io
commons-fileupload

基于SpringMVC的方式
1.配置一个文件解析器 CommonsMultipartResolver
ApplicationContext.xml（17-18）

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
       xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
       xmlns:context="http://www.springframework.org/schema/context"
       xmlns:mvc="http://www.springframework.org/schema/mvc"
       xsi:schemaLocation="http://www.springframework.org/schema/beans
        https://www.springframework.org/schema/beans/spring-beans.xsd
        http://www.springframework.org/schema/context
        https://www.springframework.org/schema/context/spring-context.xsd
        http://www.springframework.org/schema/mvc
        https://www.springframework.org/schema/mvc/spring-mvc.xsd">
    <!--将刚才的bean标签配置去掉 改为开启注解扫描-->
    <context:component-scan base-package="controller"></context:component-scan>
    <mvc:annotation-driven></mvc:annotation-driven>
    <!--配置文件解析器-->
    <bean id="multipartResolver" class="org.springframework.web.multipart.commons.CommonsMultipartResolver"></bean>
</beans>

2.自己写一个Controller
方法内部像之前一样接收参数即可
文件参数MultipartFile类型变量名与前面的key一致（index.jsp第9行）
TestController

package controller;

import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.multipart.MultipartFile;

import java.io.File;
import java.io.IOException;

@Controller
public class TestController {

    //原生方式处理文件的上传
    /**@RequestMapping("upload.do")
    public String upload(HttpServletRequest request) throws Exception {
        //获取磁盘文件选项的factory
        DiskFileItemFactory factory = new DiskFileItemFactory();
        //创建一个ServletFileUpload对象
        ServletFileUpload upload = new ServletFileUpload(factory);
        //让upload对象帮我们去解析request(目的获取数据)
        List<FileItem> itemList = upload.parseRequest(request);
        //遍历所有的文件项
        for(FileItem item : itemList){
            //每次循环判断一下当前item是文件还是普通表单对象
            if(item.isFormField()){//普通表单数据
                String key = item.getFieldName();
                String value = item.getString("UTF-8");
                System.out.println(key+"--"+value);
            }else{//文件数据
                String fileName = item.getName();//名字可以自己弄一个规则 确保文件名唯一  UUID
                item.write(new File("D://test//",fileName));
            }
        }
        return "welcome.jsp";
    }
*/
    //文件上传的时候需要一个临时存储
    //factory.setSizeThreshold(1024000);//设置缓存大小
    //factory.setRepository(new File("路径"));

    @RequestMapping("upload.do")
    public String upload(String text, MultipartFile upload) throws IOException {
        System.out.println(text);
        //文件名字
        String fileName=upload.getOriginalFilename();
        //文件对象
        //upload对象帮我们做传输
        upload.transferTo(new File("D://",fileName));
        return "welcome.jsp";
    }


}

index.jsp

<%@ page contentType="text/html;charset=UTF-8" language="java" %>
<html>
  <head>
  </head>
  <body>

    <form action="upload.do" method="post" enctype="multipart/form-data">
      <input type="text" name="text" value=""><br>
      <input type="file" name="upload"><br>
      <input type="submit" value="upload">
    </form>

  </body>
</html>

3.用MultipartFile对象做文件的传输
transferTo(new File(“上传路径”)) ——-TestController48行