目录:
接着上一篇,添加需要的依赖包:
compile group: 'commons-io', name: 'commons-io', version: '2.4'
compile group: 'commons-fileupload', name: 'commons-fileupload', version: '1.3.1'
// https://mvnrepository.com/artifact/javax.servlet/javax.servlet-api
compile group: 'javax.servlet', name: 'javax.servlet-api', version: '3.1.0'
在java/com.java.controller下新建一个FileController.java,内容如下:
package com.java.controller;
import org.apache.commons.io.FileUtils;
import org.springframework.http.HttpHeaders;
import org.springframework.http.HttpStatus;
import org.springframework.http.MediaType;
import org.springframework.http.ResponseEntity;
import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestParam;
import org.springframework.web.multipart.MultipartFile;
import javax.servlet.http.HttpServletRequest;
import java.io.File;
import java.net.URLEncoder;
import java.util.List;
import java.util.UUID;
@Controller
public class FileController {
@RequestMapping("/toFileUpload")
public String toFileUpload(){
return "/fileUpload";
}
@RequestMapping("/fileUpload")
public String handleFormUpload(@RequestParam("name") String name,
@RequestParam("uploadfile") List<MultipartFile> uploadfile,
HttpServletRequest request) {
// 判断所上传文件是否存在
if (!uploadfile.isEmpty() && uploadfile.size() > 0) {
//循环输出上传的文件
for (MultipartFile file : uploadfile) {
// 获取上传文件的原始名称
String originalFilename = file.getOriginalFilename();
// 设置上传文件的保存地址目录
String dirPath ="D:/upload/";
File filePath = new File(dirPath);
// 如果保存文件的地址不存在,就先创建目录
if (!filePath.exists()) {
filePath.mkdirs();
}
// 使用UUID重新命名上传的文件名称(上传人_uuid_原始文件名称)
String newFilename = name+ "_"+ UUID.randomUUID() +
"_"+originalFilename;
try {
// 使用MultipartFile接口的方法完成文件上传到指定位置
file.transferTo(new File(dirPath + newFilename));
} catch (Exception e) {
e.printStackTrace();
return "/error";
}
}
// 跳转到成功页面
return "/success";
}else{
return "/error";
}
}
@RequestMapping("/toDownload")
public String toDownload(){
return "/download";
}
@RequestMapping("/download")
public ResponseEntity<byte[]> fileDownload(HttpServletRequest request,
String filename) throws Exception{
// 指定要下载的文件所在路径
String path ="D:/upload/";
// 创建该文件对象
File file = new File(path+File.separator+filename);
// 对文件名编码,防止中文文件乱码
filename = this.getFilename(request, filename);
// 设置响应头
HttpHeaders headers = new HttpHeaders();
// 通知浏览器以下载的方式打开文件
headers.setContentDispositionFormData("attachment", filename);
// 定义以流的形式下载返回文件数据
headers.setContentType(MediaType.APPLICATION_OCTET_STREAM);
// 使用Sring MVC框架的ResponseEntity对象封装返回下载数据
return new ResponseEntity<byte[]>(FileUtils.readFileToByteArray(file),
headers, HttpStatus.OK);
}
/**
* 根据浏览器的不同进行编码设置,返回编码后的文件名
*/
public String getFilename(HttpServletRequest request,
String filename) throws Exception {
// IE不同版本User-Agent中出现的关键词
String[] IEBrowserKeyWords = {"MSIE", "Trident", "Edge"};
// 获取请求头代理信息
String userAgent = request.getHeader("User-Agent");
for (String keyWord : IEBrowserKeyWords) {
if (userAgent.contains(keyWord)) {
//IE内核浏览器,统一为UTF-8编码显示
return URLEncoder.encode(filename, "UTF-8");
}
}
//火狐等其它浏览器统一为ISO-8859-1编码显示
return new String(filename.getBytes("UTF-8"), "ISO-8859-1");
}
}
修改resources->config->springmvc.xml,添加上文件上传需要的配置,如下:
<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
xmlns:mvc="http://www.springframework.org/schema/mvc"
xmlns:aop="http://www.springframework.org/schema/aop"
xmlns:context="http://www.springframework.org/schema/context"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="
http://www.springframework.org/schema/beans
http://www.springframework.org/schema/beans/spring-beans.xsd
http://www.springframework.org/schema/context
http://www.springframework.org/schema/context/spring-context.xsd
http://www.springframework.org/schema/mvc
http://www.springframework.org/schema/mvc/spring-mvc.xsd
http://www.springframework.org/schema/aop
http://www.springframework.org/schema/aop/spring-aop.xsd ">
<!--springmvc的扫描包,识别@Controller,生成bean-->
<context:component-scan base-package="com.java"/>
<!--注解驱动配置-->
<mvc:annotation-driven>
<mvc:message-converters>
<!--避免json数据传输乱码-->
<bean class="org.springframework.http.converter.StringHttpMessageConverter">
<!--<property name="supportedMediaTypes" value="text/html;charset=UTF-8"/>-->
<property name="supportedMediaTypes">
<list>
<value>text/html;charset=UTF-8</value>
<value>application/json;charset=UTF-8</value>
</list>
</property>
</bean>
<bean class="org.springframework.http.converter.json.MappingJackson2HttpMessageConverter">
</bean>
</mvc:message-converters>
</mvc:annotation-driven>
<!--视图解析器配置-->
<bean id="viewResol" class="org.springframework.web.servlet.view.InternalResourceViewResolver">
<!--前缀属性,/WEB-INF/views/cgi-->
<property name="prefix" value="/WEB-INF/views"/>
<!--后缀属性-->
<property name="suffix" value=".jsp"/>
</bean>
<!--文件上传-->
<bean id="multipartResolver" class="org.springframework.web.multipart.commons.CommonsMultipartResolver">
<!--设置文件上传编码-->
<property name="defaultEncoding" value="UTF-8"/>
<!--设置允许上传文件的最大值(2M))-->
<property name="maxUploadSize" value="2097152"/>
<!--设置缓存中的最大值(2M))-->
<property name="maxInMemorySize" value="2097152"/>
</bean>
</beans>
在webapp->WEB-INF->views下新建fileUpload.jsp、download.jsp、success.jsp、error.jsp,如下:
fileUpload.jsp
<%@ page language="java" contentType="text/html; charset=UTF-8"
pageEncoding="UTF-8" %>
<!DOCTYPE html>
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
<title>文件上传</title>
<script>
function check() {
//通过标签的id属性获取属性值
var name = document.getElementById("name").value;
var file = document.getElementById("file").value;
if (name == "") {
alert("上传人未填写");
return false;
}
if (file.length == 0 || file == "") {
alert("请选择上传文件");
return false;
}
return true;
}
</script>
</head>
<body>
<form action="${pageContext.request.contextPath }/fileUpload"
method="post" enctype="multipart/form-data" onsubmit="return check()">
上传人:<input id="name" type="text" name="name"/><br/><br/>
请选择文件:<input id="file" type="file" name="uploadfile"
multiple="multiple"/><br/><br/>
<input type="submit" value="上传"/>
</form>
</body>
</html>
download.jsp
<%@ page language="java" contentType="text/html; charset=UTF-8"
pageEncoding="UTF-8" %>
<%@page import="java.net.URLEncoder" %>
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"
"http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
<title>下载页面</title>
</head>
<body>
<%-- <a href="${pageContext.request.contextPath }/download?filename=1.jpg">
文件下载
</a> --%>
<a href="${pageContext.request.contextPath }/download?filename=<%=
URLEncoder.encode("壁纸.jpg", "UTF-8")%>">
中文名称文件下载
</a>
</body>
</html>
success.jsp
<%@ page contentType="text/html;charset=UTF-8" language="java" %>
<html>
<head>
<title>$Title$</title>
</head>
<body>
success
</body>
</html>
error.jsp
<%@ page contentType="text/html;charset=UTF-8" language="java" %>
<html>
<head>
<title>$Title$</title>
</head>
<body>
error
</body>
</html>
这里我是在电脑D盘新建一个叫upload的文件夹(可自行新建取名,但使用的时候要用自己新建那个)。
如下图点击进入:
然后点击+,选择External Source…,选择上面我们新建的upload文件夹并确定,还要填写右边Application context,这里我填了/upload,如下:
图片上传测试
在浏览器中输入这个链接:http://localhost:8080/toFileUpload,效果如下:
图片下载测试
在浏览器中输入这个链接:http://localhost:8080/toDownload,效果如下: