标签：输出 can fail lte api buffer cto reg let
文件配置
<?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"> <!-- 1.注解驱动--> <mvc:annotation-driven/> <!-- 2.静态资源过滤--> <mvc:default-servlet-handler/> <!--解决json前端的乱码--> <mvc:annotation-driven> <mvc:message-converters register-defaults="true"> <bean class="org.springframework.http.converter.StringHttpMessageConverter"> <constructor-arg value="UTF-8"/> </bean> <bean class="org.springframework.http.converter.json.MappingJackson2HttpMessageConverter"> <property name="objectMapper"> <bean class="org.springframework.http.converter.json.Jackson2ObjectMapperFactoryBean"> <property name="failOnEmptyBeans" value="false"/> </bean> </property> </bean> </mvc:message-converters> </mvc:annotation-driven> <!-- 3.扫描包--> <context:component-scan base-package="com.wu.controller"/> <!-- 4.视图解析器--> <bean class="org.springframework.web.servlet.view.InternalResourceViewResolver"> <property name="prefix" value="/WEB-INF/jsp/"/> <property name="suffix" value=".jsp"/> </bean> <!-- 文件上传的配置--> <bean id="multipartResolver" class="org.springframework.web.multipart.commons.CommonsMultipartResolver"> <!--请求的编码格式，和jsp的pageEncoding属性一致--> <property name="defaultEncoding" value="utf-8"/> <!--上传文件的大小上限，单位为字节，这里是10485760=10M 可以不用配置--> <property name="maxUploadSize" value="10485760"/> <property name="maxInMemorySize" value="40960"/> </bean> </beans>
依赖导入
<dependencies> <dependency> <groupId>commons-fileupload</groupId> <artifactId>commons-fileupload</artifactId> <version>1.3.3</version> </dependency> <dependency> <groupId>javax.servlet</groupId> <artifactId>javax.servlet-api</artifactId> <version>4.0.1</version> </dependency> </dependencies>
web.xml
<?xml version="1.0" encoding="UTF-8"?> <web-app xmlns="http://xmlns.jcp.org/xml/ns/javaee" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://xmlns.jcp.org/xml/ns/javaee http://xmlns.jcp.org/xml/ns/javaee/web-app_4_0.xsd" version="4.0"> <servlet> <servlet-name>springmvc</servlet-name> <servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class> <init-param> <param-name>contextConfigLocation</param-name> <param-value>classpath:applicationContext.xml</param-value> </init-param> <load-on-startup>1</load-on-startup> </servlet> <servlet-mapping> <servlet-name>springmvc</servlet-name> <url-pattern>/</url-pattern> </servlet-mapping> <filter> <filter-name>encoding</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> </filter> <filter-mapping> <filter-name>encoding</filter-name> <url-pattern>/*</url-pattern> </filter-mapping> </web-app>
index.jsp
<%@ page contentType="text/html;charset=UTF-8" language="java" %> <html> <head> <title>$Title$</title> </head> <body> <form action="${pageContext.request.contextPath}/upload" enctype="multipart/form-data" method="post"> <input type="file" name="file"> <input type="submit" value="upload"> </form> </body> </html>
上传与下载的controller：
@RestController public class FileController { //@RequestParam(file) 将name=file控件得到的文件封装成CommonsMultipartFile对象 //批量上传CommonsMultipartFile数组即可 @RequestMapping("/upload") public String upload(@RequestParam("file") CommonsMultipartFile file, HttpServletRequest request) throws IOException { //获取文件名： String uploadFileName = file.getOriginalFilename(); //如果文件名为空，直接回到首页 if ("".equals(uploadFileName)) { return "redirect:/index.jsp"; } System.out.println("上传的文件名为 " + uploadFileName); //上传路径保存设置 String path = request.getServletContext().getRealPath("/upload"); //路径不存在的话就创建一个 File realPath = new File(path); if (!realPath.exists()) { realPath.mkdirs(); } System.out.println("上传文件的保存地址为 " + realPath); InputStream is = file.getInputStream();//文件的输入流 OutputStream os = new FileOutputStream(new File(realPath, uploadFileName));//文件输出流 //读取写出 int len = 0; byte[] buffer = new byte[1024]; while ((len = is.read(buffer)) != -1) { os.write(buffer, 0, len); os.flush(); } os.close(); is.close(); return "redirect:/index.jsp"; } @RequestMapping("/update2") public String upload2(@RequestParam("file") CommonsMultipartFile file, HttpServletRequest request) throws IOException { //上传路径保存设置 String path = request.getServletContext().getRealPath("/upload"); File realPath = new File(path); if (!realPath.exists()) { realPath.mkdirs(); } //上传文件地址 System.out.println("上传文件保存地址：" + realPath); //使用transferTo直接写文件 file.transferTo(new File(realPath + "/" + file.getOriginalFilename())); return "redirect:/index.jsp"; } @RequestMapping("/download") public String download(HttpServletResponse response, HttpServletRequest request) throws Exception { //要下载的图片地址 String path = request.getServletContext().getRealPath("/upload"); String fileName = "123.jpg"; //1.设置响应头 response.reset();//设置页面不缓存，清空buffer response.setCharacterEncoding("UTF-8"); response.setContentType("multipart/form-data");//二进制传输数据 //设置响应头 response.setHeader("Content-Disposition", "attachment;fileName=" + URLEncoder.encode(fileName, "UTF-8")); File file = new File(path, fileName); //2.读取文件--输入流 InputStream inputStream = new FileInputStream(file); //3.写出文件--输出流 OutputStream outputStream = response.getOutputStream(); byte[] buff = new byte[1024]; int index = 0; //4.执行写出操作 while ((index = inputStream.read(buff)) != -1) { outputStream.write(buff, 0, index); outputStream.flush(); } outputStream.close(); inputStream.close(); return "ok"; } }
标签：输出 can fail lte api buffer cto reg let
原文地址：https://www.cnblogs.com/wuyimin/p/14883524.html
