SSM文件的上传与下载

小咪咪 2023-10-13 11:24 12阅读 0赞

##### 1.在自己已经构建好的maven web项目中 pom.xml配置文件中添加上传下载所需要的jar包 #####

<dependency>
                <groupId>commons-fileupload</groupId>
                <artifactId>commons-fileupload</artifactId>
                <version>1.3.1</version>
            </dependency>

##### 2.在spring的applicationContext.xml配置文件中添加文件上传解析器 #####

<bean id="multipartResolver" class="org.springframework.web.multipart.commons.CommonsMultipartResolver">
            
            <property name="defaultEncoding" value="utf-8"/>
            
            <property name="maxUploadSize" value="10485760"/>
            
            <property name="maxInMemorySize" value="4096000"/>
        </bean>

##### 3.文件上传 #####

前台页面：

后台实现：

//@RequestParam("file")将name=file控件得到的文件封装成CommonsMultipartFile对象
        //批量上传CommonsMultipartFile则为数组即可
        @RequestMapping("/upload222")
        public String fileUpload(@RequestParam("file") MultipartFile file , HttpServletRequest request) throws IOException {
                //上传路径保存设置  服务器路径 E:\apache-tomcat-8.5.87\webapps\ROOT
                //String path = request.getSession().getServletContext().getRealPath("/static/upload");
                //tomcat根目录 E:\apache-tomcat-8.5.87\webapps
                // upload\file
                File path = new File(request.getSession().getServletContext().getRealPath("/")).getParentFile();
                String savePath = "/upload/file/";
                File realPath = new File(path+savePath);
                if (!realPath.exists()){
                    realPath.mkdirs();
                }
                //上传文件地址
                System.out.println("上传文件保存地址：" + realPath);
    
                //通过CommonsMultipartFile的方法直接写文件
                //System.currentTimeMillis()根据系统时间产生随机数，保证上传的图片名字不一样
                //UUID.randomUUID()
                String filename=UUID.randomUUID()+"_"+file.getOriginalFilename();
                file.transferTo(new File(realPath + "/" + filename));
    
    
                /*String url=path.getPath()+"/upload/file/"+filename;
                System.out.println("URL"+url);*/
                return "redirect:/index.jsp";
        }

##### 4.文件下载 #####

前台页面：

后台实现：

@RequestMapping("/download222")
        public String downloads(String fileNames,HttpServletResponse response , HttpServletRequest request) throws Exception{
            //要下载的图片地址  E:\apache-tomcat-8.5.87\webapps\ROOT
            //String path = request.getSession().getServletContext().getRealPath("/static/upload");
            //String property = System.getProperty("user.dir");
            File path = new File(request.getSession().getServletContext().getRealPath("/")).getParentFile();
            String savePath = "/upload/file/";
            String fileName = savePath+"/"+"87ea4c0d-7e48-46d2-9ff2-4283a1ab7699_签名.png";
    
            //1.设置response响应头
            response.reset();//设置页面不缓存，清空buffer
            response.setCharacterEncoding("UTF-8");//字符编码
            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);
            OutputStream os = response.getOutputStream();
            // 读取文件
            InputStream in = new FileInputStream(file);
            // copy文件
            IOUtils.copy(in, os);
            in.close();
            os.close();
    
    
            return null;
    
        }