springMVC实现文件的上传

爱被打了一巴掌 2022-05-30 01:36 310阅读 0赞

springMVC实现文件上传：导入jar包 ----- 配置文件 ----- 提交表单 ----- controller层定义方法

一、导入jar包

jar包：    com.springsource.org.apache.commons.fileupload-1.2.0.jar

com.springsource.org.apache.commons.io-1.4.0.jar

二、xxx-servlet.xml配置文件

注意：主要配置id="multipartResolver"的bean标签，其他为基本配置（用的是注解）

<?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:mvc="http://www.springframework.org/schema/mvc"
        xmlns:aop="http://www.springframework.org/schema/aop"
        xmlns:tx="http://www.springframework.org/schema/tx"
        xmlns:context="http://www.springframework.org/schema/context"
        xsi:schemaLocation="
       http://www.springframework.org/schema/beans
       http://www.springframework.org/schema/beans/spring-beans-3.0.xsd
       http://www.springframework.org/schema/aop
       http://www.springframework.org/schema/aop/spring-aop-3.0.xsd
       http://www.springframework.org/schema/tx
       http://www.springframework.org/schema/tx/spring-tx-3.0.xsd
       http://www.springframework.org/schema/mvc
       http://www.springframework.org/schema/mvc/spring-mvc-3.0.xsd
       http://www.springframework.org/schema/context     
       http://www.springframework.org/schema/context/spring-context-3.0.xsd">
    	
       	<mvc:annotation-driven/>
    	<context:component-scan base-package="com.hfxt.controller"></context:component-scan>	
    	 
    	<bean class="org.springframework.web.servlet.view.InternalResourceViewResolver">
    		<property name="prefix" value="/WEB-INF/page/"/>
    		<property name="suffix" value=".jsp"/>
    	</bean>
    	
    	<bean id="multipartResolver" class="org.springframework.web.multipart.commons.CommonsMultipartResolver">
    		<property name="maxUploadSize" value="1024000"></property>
    	</bean>
    	<mvc:resources location="/js/" mapping="/js/**"/>
    </beans>

三、jsp页面表单提交

注意：<form>标签的    method="post"     和     enctype="multipart/form-data"    必不可少。

<?xml version="1.0" encoding="UTF-8" ?>
    <%@ page language="java" contentType="text/html; charset=UTF-8"
        pageEncoding="UTF-8"%>
    <!DOCTYPE html >
    <html xmlns="http://www.w3.org/1999/xhtml">
    <head>
    <meta http-equiv="Content-Type" content="text/html; charset=UTF-8" />
    <title>注册用户</title>
    </head>
    <body>
    	<form id="myForm" action="/spring_mvc_annotation/upload" method="post" enctype="multipart/form-data">
    		用户名：<input type="text" name="username" /><br />
    		密码：<input type="password" name="password" /><br />
    		照片：<input type="file" name="photo"/><br />
    		<input type="submit" value="注册"/>
    	</form>
    </body>
    </html>

四、controller层定义方法

package com.hfxt.controller;
    
    import java.io.File;
    
    import java.net.URLEncoder;
    import java.text.SimpleDateFormat;
    import java.util.Date;
    
    import javax.servlet.http.HttpServletRequest;
    import javax.servlet.http.HttpServletResponse;
    import javax.servlet.http.HttpSession;
    import org.springframework.stereotype.Controller;
    import org.springframework.ui.Model;
    import org.springframework.web.bind.annotation.RequestMapping;
    import org.springframework.web.bind.annotation.RequestMethod; 
    import org.springframework.web.multipart.MultipartHttpServletRequest;
    import org.springframework.web.multipart.commons.CommonsMultipartFile;
    
    import com.hfxt.entity.User;
    @Controller
    @RequestMapping(value="/")
    public class LoginController {
    	//注册页面（由于放在/web-inf/page目录下，所以定义该方法）
    	@RequestMapping(value="/register",method=RequestMethod.GET)
    	public String toRegister(){
    		return "register";
    	}
            //文件上传
    	@RequestMapping(value="/upload",method=RequestMethod.POST)
    	public String upload(User user, HttpServletRequest httpServletRequest ,Model model){
    		System.out.println(user.getUsername());
    		
    		try {
    			//转换成MultipartHttpServletRequest（继承了HttpServletRequest, MultipartRequest）
    			MultipartHttpServletRequest request = (MultipartHttpServletRequest) httpServletRequest;
    			
    			//用MultipartHttpServletRequest对象获取文件，CommonsMultipartFile实现了MultipartFile接口
    			CommonsMultipartFile cmFile = (CommonsMultipartFile) request.getFile("photo");//photo为表单的file的name
    			
    			//获取文件的字节数字，方便后面的写操作
    			byte[] buf = cmFile.getBytes();
    			
    			//获取原始文件的名称和后缀
    			String originalFilename = cmFile.getOriginalFilename();
    			String suffix = originalFilename.substring(originalFilename.lastIndexOf("."));//文件后缀名
    			
    			/*获取当前项目的真实路径，request.getSession().getServletContext() 获取的是Servlet容器对象，
    			相当于tomcat容器了。getRealPath("/") 获取实际路径，“/”指代项目根目录，
    			所以代码返回的是项目在容器中的实际发布运行的根路径*/
    			String path=request.getSession().getServletContext().getRealPath("/");
    			
    			//设置要保存的文件名称：这里以当前时间到毫秒，还可以加随机数
    			Date date = new Date();
    			SimpleDateFormat sdf =new SimpleDateFormat("yyyyMMddHHmmssSSS");
    			String fileName = sdf.format(date);//当前时间作为文件名
    			
    			//构造url（根目录+upload文件夹+文件名+后缀），为了方便在数据库中存取
    			String url = path+"upload\\"+fileName+suffix;
    			System.out.println(url);
    			
    			//创建upload文件夹
    			File dir = new File(path+"upload");
    			if(!dir.exists()){
    				dir.mkdir();//创建单级文件夹
    		}
    		
    			//写文件
    			OutputStream os = new FileOutputStream(url);
    			os.write(buf);
    			os.close();
    			
    			//判断上传成功与否（我这里比较简单，不够严谨）
    			File uploadFile = new File(url);
    			String message="";
    			if(!uploadFile.exists()){
    				message="上传失败！";
    			}else{
    				message="上传成功！";
    			}
    			//保存url，下载会用到
    			user.setUrl(URLEncoder.encode(url,"UTF-8"));//url编码，下载时需要解码
    			/*System.out.println("编码后url："+user.getUrl());*/
    			
    			model.addAttribute(user);
    			model.addAttribute("message",message);
    			
    		} catch (Exception e) {
    			e.printStackTrace();
    		}
    		return "register_success";
    	}
    	
    }

一个基本的文件上传功能就实现了。

文件下载参照：[http://blog.csdn.net/lpch0825/article/details/79410680][http_blog.csdn.net_lpch0825_article_details_79410680]

[http_blog.csdn.net_lpch0825_article_details_79410680]: http://blog.csdn.net/lpch0825/article/details/79410680