springmvc上传与下载-编程知识

文件上传

结构图

在这里插入图片描述

导入依赖

<dependency><groupId>jstl</groupId><artifactId>jstl</artifactId><version>1.2</version></dependency><dependency><groupId>org.springframework</groupId><artifactId>spring-webmvc</artifactId><version>5.2.8.RELEASE</version></dependency><dependency><groupId>commons-fileupload</groupId><artifactId>commons-fileupload</artifactId><version>1.4</version></dependency><dependency><groupId>junit</groupId><artifactId>junit</artifactId><version>4.12</version><scope>test</scope></dependency><dependency><groupId>javax.servlet</groupId><artifactId>javax.servlet-api</artifactId><version>3.0.1</version></dependency>

web.xml配置

<?xml version="1.0" encoding="UTF-8" ?>
<web-app xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"xmlns="http://xmlns.jcp.org/xml/ns/javaee"xsi:schemaLocation="http://xmlns.jcp.org/xml/ns/javaee http://xmlns.jcp.org/xml/ns/javaee/web-app_3_1.xsd"id="WebApp_ID" version="3.1"><display-name>Archetype Created Web Application</display-name><servlet><servlet-name>dispatcherServlet</servlet-name><servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class><init-param><param-name>contextConfigLocation</param-name><param-value>classpath:spring.xml</param-value></init-param><!--启动顺序--><load-on-startup>1</load-on-startup></servlet><servlet-mapping><servlet-name>dispatcherServlet</servlet-name><url-pattern>/</url-pattern></servlet-mapping><filter><filter-name>encodingFilter</filter-name><filter-class>org.springframework.web.filter.CharacterEncodingFilter</filter-class><init-param><param-name>encoding</param-name><param-value>UTF-8</param-value></init-param><init-param><param-name>forceEncoding</param-name><param-value>true</param-value></init-param></filter><filter-mapping><filter-name>encodingFilter</filter-name><url-pattern>/*</url-pattern></filter-mapping>
</web-app>

上传一个或多个文件

index.jsp代码

<%@ taglib prefix="c" uri="http://java.sun.com/jsp/jstl/core" %>
<%@ page contentType="text/html;charset=UTF-8" language="java" %>
<html>
<head><title>Title</title>
</head>
<body>
<form method="post" action="file" enctype="multipart/form-data">上传文件：<input type="file" name="picture"><input type="submit" value="提交">
</form><hr>
<h1>多文件</h1>
<form method="post" action="files" enctype="multipart/form-data">上传文件1：<input type="file" name="pictures">上传文件2：<input type="file" name="pictures">上传文件3：<input type="file" name="pictures"><input type="submit" value="提交">
</form>
</body>
</html>

WEB-INF下的success.jsp代码

在这里插入图片描述

spring.xml

<?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 http://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"><context:component-scan base-package="com.tmg"></context:component-scan>
<!--    视图解析器--><bean id="viewResolver" class="org.springframework.web.servlet.view.InternalResourceViewResolver"><property name="prefix" value="/WEB-INF/pages/"/><property name="suffix" value=".jsp"/></bean>
<!--    静态资源处理器--><mvc:default-servlet-handler></mvc:default-servlet-handler>
<!--    注解驱动--><mvc:annotation-driven></mvc:annotation-driven>
<!--    文件上传处理器--><bean id="multipartResolver" class="org.springframework.web.multipart.commons.CommonsMultipartResolver"><property name="defaultEncoding" value="UTF-8"></property><property name="maxUploadSize" value="10485760"></property></bean>
</beans>

FileController代码

运行的时候，浏览器页面要在WEB-INF下的index.jsp，跑完该项目时，页面是webapp下的index.jsp,所以跑完之后切换请求路径（/toFile）进入WEB-INF下的index.jsp

package com.tmg.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 FileController {private static final String DIR = "D:\\picture\\";@RequestMapping("/toFile")public String text() {return "/index";}@RequestMapping("file")public String text1(MultipartFile picture) throws IOException {String filename = picture.getOriginalFilename();picture.transferTo(new File(DIR, filename));return "success";}@RequestMapping("/files")public String text2(MultipartFile[] pictures) {try {for (MultipartFile picture : pictures) {String filename = picture.getOriginalFilename();if("".equals(filename)){continue;}picture.transferTo(new File(DIR, filename));System.out.println(filename);}} catch (IOException e) {e.printStackTrace();} finally {return "success";}}}

文件下载

DownloadController代码

跑的时候记得在路径带上 file=XXX ，并在执行前指定自己下载目录

package com.tmg.controller;import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.RequestMapping;import javax.servlet.http.HttpServletResponse;
import java.io.File;
import java.io.IOException;
import java.nio.file.Files;/*** 下载控制器*/
@Controller
public class DownloadController {@RequestMapping("/download")public void download(String file,  HttpServletResponse response) throws IOException {//下载文件的路径String path = "D:\\picture\\";File downFile = new File(path+file);if(downFile.exists()){//设置浏览器下载内容类型，响应头response.setContentType("application/x-msdownload");response.setHeader("Content-Disposition","attachment;filename="+file);//通过流发送文件Files.copy(downFile.toPath(),response.getOutputStream());}}
}