springmvc整合CommonsMultipartResolver文件上传

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我是靠谱客的博主淡然母鸡，最近开发中收集的这篇文章主要介绍springmvc整合CommonsMultipartResolver文件上传，觉得挺不错的，现在分享给大家，希望可以做个参考。

概述

spring mvc的文件上传模块是可插拔的，默认没有启用，只要在 spring mvc 容器中实例化 MultipartResolver 接口的实现类即可，spring mvc 为我们提供了整合了 commons-fileupload 的 CommonsMultipartResolver 解析器，只需实例化该类即可。

配置文件

<?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:jdbc="http://www.springframework.org/schema/jdbc"  
    xmlns:jee="http://www.springframework.org/schema/jee" 
    xmlns:tx="http://www.springframework.org/schema/tx"
    xmlns:aop="http://www.springframework.org/schema/aop" 
    xmlns:mvc="http://www.springframework.org/schema/mvc"
    xmlns:util="http://www.springframework.org/schema/util"
    xmlns:jpa="http://www.springframework.org/schema/data/jpa"
    xsi:schemaLocation="
        http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-3.2.xsd
        http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context-3.2.xsd
        http://www.springframework.org/schema/jdbc http://www.springframework.org/schema/jdbc/spring-jdbc-3.2.xsd
        http://www.springframework.org/schema/jee http://www.springframework.org/schema/jee/spring-jee-3.2.xsd
        http://www.springframework.org/schema/tx http://www.springframework.org/schema/tx/spring-tx-3.2.xsd
        http://www.springframework.org/schema/data/jpa http://www.springframework.org/schema/data/jpa/spring-jpa-1.3.xsd
        http://www.springframework.org/schema/aop http://www.springframework.org/schema/aop/spring-aop-3.2.xsd
        http://www.springframework.org/schema/mvc http://www.springframework.org/schema/mvc/spring-mvc-3.2.xsd
        http://www.springframework.org/schema/util http://www.springframework.org/schema/util/spring-util-3.2.xsd">
      
    <mvc:annotation-driven/>  
    <context:component-scan base-package="com.troy"/>
    <bean class="org.springframework.web.servlet.view.InternalResourceViewResolver">
        <property name="prefix" value="/WEB-INF/page/"/>
        <property name="suffix" value=".jsp"/>
    </bean>
    <bean id="commonsMultipartResolver" class="org.springframework.web.multipart.commons.CommonsMultipartResolver">
        <property name="defaultEncoding" value="utf-8"/>
 <!-- 最大文件大小，单位字节 -->
        <property name="maxUploadSize" value="100000"/> 
    </bean>
</beans>

解析器id必须是multipartResolver，否则spring将在上传超过3m文件时会报错！！！

jsp

<%@ page language="java" contentType="text/html; charset=utf-8"
    pageEncoding="utf-8"%>
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<%
    String path = request.getContextPath();
    String basePath = request.getScheme()+"://"+request.getServerName()+":"+request.getServerPort()+path+"/";
%>
<html>
<head>
<base href="<%=basePath%>">
<meta http-equiv="Content-Type" content="text/html; charset=utf-8">
<title>Insert title here</title>
<script type="text/javascript" src="js/jquery-3.1.1.min.js"></script>
</head>
<body>
    <form action="file/upLoad" method="post" enctype="multipart/form-data">
        <input type="file" name="file"/>
        <input type="submit" value="上传"/>
    </form>
</body>
</html>

java后台

@RequestMapping(value="/file")
@Controller
public class FileController {
    
    @RequestMapping(value="/init")
    public String init(){
        
        return "file";
    }
    
    @RequestMapping(value="/upLoad")
    @ResponseBody
    public void upLoad(HttpServletRequest request) throws Exception{
        
        //创建一个多分解的容器
        CommonsMultipartResolver cmr = new CommonsMultipartResolver(request.getSession().getServletContext());
        //设置编码
        cmr.setDefaultEncoding("utf-8");
        //判断是否有文件上传
        if(cmr.isMultipart(request)){
            //将request转换成多分解请求
            MultipartHttpServletRequest mhs = cmr.resolveMultipart(request);
            //根据input中存在的name来获取是否存在上传文件
            MultipartFile mf = mhs.getFile("file");#这里可以用getFiles("file")的方式来处理多个文件。返回的是一个list.然后一个一个处理就可以了
            //创建文件保存名
            File file = new File(mf.getOriginalFilename());
            //上传文件
            mf.transferTo(file);
        }
    }
}

使用MultipartFile类的相关API完成文件上传

@Controller
public class FileUploadController {
    private static final String UPLOAD_DIR = "/srv/www/upload/";
    private static final long MAX_FILE_SISE = 1000000;

    @RequestMapping("/upload")
    public void uploadFile(@RequestParam("file") MultipartFile file) {
        if(!file.isEmpty()) {
            //获取文件类型
            String contentType = file.getContentType();
            if(!contentType.equals("")) {
                //可以对文件类型进行检查
            }
            //获取input域的name属性
            String name = file.getName();
            //获取文件名，带扩展名
            String originFileName = file.getOriginalFilename();
            //获取文件扩展名
            String extension = originFileName.substring(originFileName.lastIndexOf("."));
            System.out.println(extension);
            //获取文件大小，单位字节
            long site = file.getSize();
            if(site > MAX_FILE_SISE) {
                //可以对文件大小进行检查
            }
            //构造文件上传后的文件绝对路径，这里取系统时间戳＋文件名作为文件名
            //不推荐这么写，这里只是举例子，这么写会有并发问题
            //应该采用一定的算法生成独一无二的的文件名
            String fileName = UPLOAD_DIR + String.valueOf(System.currentTimeMillis()) + extension;
            try {
                file.transferTo(new File(fileName));
            } catch (Exception e) {
                e.printStackTrace();
            }
        }
    }
}