导入maven依赖
1 <dependencies>
2 <!--文件上传-->
3 <dependency>
4 <groupId>commons-fileupload</groupId>
5 <artifactId>commons-fileupload</artifactId>
6 <version>1.3.3</version>
7 </dependency>
8 <!--servlet-api 导入高版本-->
9 <dependency>
10 <groupId>javax.servlet</groupId>
11 <artifactId>javax.servlet-api</artifactId>
12 <version>4.0.1</version>
13 </dependency>
14 </dependencies>配置web.xml
1 <?xml version="1.0" encoding="UTF-8"?>
2 <web-app xmlns="http://xmlns.jcp.org/xml/ns/javaee"
3 xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
4 xsi:schemaLocation="http://xmlns.jcp.org/xml/ns/javaee http://xmlns.jcp.org/xml/ns/javaee/web-app_4_0.xsd"
5 version="4.0">
6
7 <servlet>
8 <servlet-name>DispatcherServlet</servlet-name>
9 <servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class>
10 <init-param>
11 <param-name>contextConfigLocation</param-name>
12 <param-value>classpath:applicationContext.xml</param-value>
13 </init-param>
14 <load-on-startup>1</load-on-startup>
15 </servlet>
16
17 <servlet-mapping>
18 <servlet-name>DispatcherServlet</servlet-name>
19 <url-pattern>/</url-pattern>
20 </servlet-mapping>
21
22
23 <!--防止中文乱码-->
24 <filter>
25 <filter-name>encoding</filter-name>
26 <filter-class>org.springframework.web.filter.CharacterEncodingFilter</filter-class>
27 <init-param>
28 <param-name>encoding</param-name>
29 <param-value>UTF-8</param-value>
30 </init-param>
31 </filter>
32 <filter-mapping>
33 <filter-name>encoding</filter-name>
34 <url-pattern>/*</url-pattern>
35 </filter-mapping>
36 </web-app>在src下的resources下建applicationContext.xml
1 <?xml version="1.0" encoding="UTF-8"?>
2 <beans xmlns="http://www.springframework.org/schema/beans"
3 xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
4 xmlns:context="http://www.springframework.org/schema/context"
5 xmlns:mvc="http://www.springframework.org/schema/mvc"
6 xsi:schemaLocation="http://www.springframework.org/schema/beans
7 http://www.springframework.org/schema/beans/spring-beans.xsd
8 http://www.springframework.org/schema/context
9 http://www.springframework.org/schema/context/spring-context.xsd
10 http://www.springframework.org/schema/mvc
11 http://www.springframework.org/schema/mvc/spring-mvc.xsd">
12 <!--自动扫描包,下面注解类交给iod容器处理-->
13 <context:component-scan base-package="com.rzk.controller"/>
14 <!--静态资源过滤-->
15 <mvc:default-servlet-handler/>
16 <!--注解驱动-->
17 <mvc:annotation-driven/>
18 <!--JSON乱码问题配置-->
19 <mvc:annotation-driven>
20 <mvc:message-converters>
21 <bean class="org.springframework.http.converter.StringHttpMessageConverter">
22 <constructor-arg value="UTF-8"/>
23 </bean>
24 <bean class="org.springframework.http.converter.json.MappingJackson2HttpMessageConverter">
25 <property name="objectMapper">
26 <bean class="org.springframework.http.converter.json.Jackson2ObjectMapperFactoryBean">
27 <property name="failOnEmptyBeans" value="false"/>
28 </bean>
29 </property>
30 </bean>
31 </mvc:message-converters>
32 </mvc:annotation-driven>
33
34
35 <bean class="org.springframework.web.servlet.view.InternalResourceViewResolver">
36 <property name="prefix" value="/WEB-INF/jsp/"/>
37 <property name="suffix" value=".jsp"/>
38 </bean>
39
40 <!--文件上传配置-->
41 <bean id="multipartResolver" class="org.springframework.web.multipart.commons.CommonsMultipartResolver">
42 <!-- 请求的编码格式，必须和jSP的pageEncoding属性一致，以便正确读取表单的内容，默认为ISO-8859-1 -->
43 <property name="defaultEncoding" value="utf-8"/>
44 <!-- 上传文件大小上限，单位为字节（10485760=10M） -->
45 <property name="maxUploadSize" value="10485760"/>
46 <property name="maxInMemorySize" value="40960"/>
47 </bean>
48
49 </beans>新建上传页面
1 <form action="${pageContext.request.contextPath}/file/upload" method="post" enctype="multipart/form-data">
2 <input type="file" name="file">
3 <input type="submit" value="upload">
4 </form>controller
1 @Controller
2 @RequestMapping("/file")
3 public class FileController {
4 //@RequestParam("file") 将name=file控件得到的文件封装成CommonsMultipartFile 对象
5 //批量上传CommonsMultipartFile则为数组即可
6 @RequestMapping("/upload")
7 public String fileUpload(@RequestParam("file") CommonsMultipartFile file , HttpServletRequest request) throws IOException {
8
9 //获取文件名 : file.getOriginalFilename();
10 String uploadFileName = file.getOriginalFilename();
11
12 //如果文件名为空，直接回到首页！
13 if ("".equals(uploadFileName)){
14 return "redirect:/index.jsp";
15 }
16 System.out.println("上传文件名 : "+uploadFileName);
17
18 //上传路径保存设置
19 String path = request.getServletContext().getRealPath("/upload");
20 //如果路径不存在，创建一个
21 File realPath = new File(path);
22 if (!realPath.exists()){
23 realPath.mkdir();
24 }
25 System.out.println("上传文件保存地址："+realPath);
26
27 InputStream is = file.getInputStream(); //文件输入流
28 OutputStream os = new FileOutputStream(new File(realPath,uploadFileName)); //文件输出流
29
30 //读取写出
31 int len=0;
32 byte[] buffer = new byte[1024];
33 while ((len=is.read(buffer))!=-1){
34 os.write(buffer,0,len);
35 os.flush();
36 }
37 os.close();
38 is.close();
39 return "redirect:/index.jsp";
40 }
41 }controller第二种上传方式
1 @RequestMapping("/upload2")
2 public String fileUpload2(@RequestParam("file") CommonsMultipartFile file, HttpServletRequest request) throws IOException {
3
4 //上传路径保存设置
5 String path = request.getServletContext().getRealPath("/upload");
6 File realPath = new File(path);
7 if (!realPath.exists()){
8 realPath.mkdir();
9 }
10 //上传文件地址
11 System.out.println("上传文件保存地址："+realPath);
12
13 //通过CommonsMultipartFile的方法直接写文件（注意这个时候）
14 file.transferTo(new File(realPath +"/"+ file.getOriginalFilename()));
15
16 return "redirect:/index.jsp";
17 }
下载文件
1 @RequestMapping(value="/download")
2 public String downloads(HttpServletResponse response , HttpServletRequest request) throws Exception{
3 //要下载的图片地址
4 String path = request.getServletContext().getRealPath("/upload");
5 String fileName = "1.jpg";
6
7 //1、设置response 响应头
8 response.reset(); //设置页面不缓存,清空buffer
9 response.setCharacterEncoding("UTF-8"); //字符编码
10 response.setContentType("multipart/form-data"); //二进制传输数据
11 //设置响应头
12 response.setHeader("Content-Disposition",
13 "attachment;fileName="+ URLEncoder.encode(fileName, "UTF-8"));
14
15 File file = new File(path,fileName);
16 //2、 读取文件--输入流
17 InputStream input=new FileInputStream(file);
18 //3、 写出文件--输出流
19 OutputStream out = response.getOutputStream();
20
21 byte[] buff =new byte[1024];
22 int index=0;
23 //4、执行 写出操作
24 while((index= input.read(buff))!= -1){
25 out.write(buff, 0, index);
26 out.flush();
27 }
28 out.close();
29 input.close();
30 return "ok";
31 }链接
1 <a href="/file/download">下载</a>
下载图片只需要改一下第5行代码就可以了
