Springboot(九).多文件上传下载文件(并将url存入数据库表中)

朱雀 2021-01-10 06:33 641阅读 0赞

一．   文件上传

这里我们使用request.getSession().getServletContext().getRealPath("/static")的方式来设置文件的存储路径，并存入数据库中

request.getSession().getServletContext() 获取的是Servlet容器对象，相当于tomcat容器了。getRealPath("/") 获取实际路径，“/”指代项目根目录，所以代码返回的是项目在容器中的实际发布运行的根路径

这里我的文件就保存在了tomcat容器：C:\\Users\\Administrator\\AppData\\Local\\Temp\\tomcat-docbase.4580300150688111201.8080\\static下

当我们部署到linux的时候，文件就保存在了/tmp/tomcat-docbase.6117940652560190565.8088/static/下

Controller：

/**
     *  多文件上传接口
     * */
    @ResponseBody
    @RequestMapping(value = "/fileUpload", produces = "application/json;charset=UTF-8")
    public JSONObject fileUpload(@RequestParam("file") MultipartFile[] files, HttpServletRequest request) throws Exception{
        String serverName = "文件上传";
        VirgoLog.updateStep(CONTROLLER_NAME_DES,serverName);
        List<FileManage> fileManages = fileService.fileUpload(files,request);
        Map<String,Object> resMap = new HashMap<String,Object>();
        //0:操作成功
        resMap.put("code", ErrorCode.ERR_SUCCEED.getErrorCode());
        resMap.put("desc",ErrorCode.ERR_SUCCEED.getErrorMessage());
        resMap.put("fileInfo",fileManages);
        return JSON.parseObject(JSONConvertor.toJSON(resMap));
    }

service  文件上传业务类

/**
         * 文件上传service
         * @param files
         * @throws Exception
         */
        @Override
        public void fileUpload(@RequestParam("file")MultipartFile[] files, HttpServletRequest request) throws Exception {
            //文件命名
            //保存时的文件名
            for(int i=0;i<files.length;i++) {
                //保存文件到本地文件，并保存路径到数据库
                DateFormat df = new SimpleDateFormat("yyyyMMddHHmmss");
                Calendar calendar = Calendar.getInstance();
                String fileName = df.format(calendar.getTime()) + files[i].getOriginalFilename();
                log.log("文件的文件名为:" + fileName);
                //保存文件的绝对路径
                String filePath = request.getSession().getServletContext().getRealPath("static/");
                log.log("文件的绝对路径:" + filePath);
                FileManage fileManage = new FileManage();
                try {
                    //上传文件
                    FileUtil.uploadFile(files[i].getBytes(), filePath, fileName);
                    //保存到数据库代码，存入路径以及文件名称
                } catch (IllegalStateException | IOException e) {
                    e.printStackTrace();
                    throw new ZDYException(ErrorCode.ERR_FILE_UPLOAD_FAIL);
                }
            }
                }

文件上传工具类

/**
     * Created by hengyang4 on 2018/11/2.
     */
    public class FileUtil {
    
        //文件上传工具类服务方法
        public static void uploadFile(byte[] file, String filePath, String fileName) throws Exception{
    
            File targetFile = new File(filePath);
            if(!targetFile.exists()){
                targetFile.mkdirs();
            }
            FileOutputStream out = new FileOutputStream(filePath+fileName);
            out.write(file);
            out.flush();
            out.close();
        }
    
    }

二．    文件下载

/**
     * 文件下载service
     * @param fileId
     * @throws Exception
     */
    @Override
    public String downloadFile(String fileId, HttpServletResponse response) throws Exception {
        //这里要根据文件id在数据库中查询之前保存的文件信息    FileManage fileManage = fileManageMapper.selectByPrimaryKey(fileId);
        //文件名
        String fileName = fileManage.getFileName();
        //文件的相对路径
        String path = fileManage.getFilePath();
        InputStream inputStream = new FileInputStream(new File(path + fileName));
        //如果文件不存在
        if(inputStream == null){
            throw new ZDYException(ErrorCode.ERR_NOT_FILE);
        }
        response.setHeader("content-type", "application/octet-stream");
        response.setContentType("application/octet-stream");
        try {
            String name = java.net.URLEncoder.encode(fileName, "UTF-8");
            response.setHeader("Content-Disposition", "attachment;filename=" + name );
        } catch (UnsupportedEncodingException e2) {
            e2.printStackTrace();
        }
        byte[] buff = new byte[1024];
        BufferedInputStream bis = null;
        OutputStream os = null;
        try {
            os = response.getOutputStream();
            bis = new BufferedInputStream(inputStream);
            int i = bis.read(buff);
            while (i != -1) {
                os.write(buff, 0, buff.length);
                os.flush();
                i = bis.read(buff);
            }
        } catch (FileNotFoundException e1) {
            //e1.getMessage()+"系统找不到指定的文件";
            throw new ZDYException(ErrorCode.ERR_NOT_FILE);
        }catch (IOException e) {
            e.printStackTrace();
        } finally {
            if (bis != null) {
                try {
                    bis.close();
                } catch (IOException e) {
                    e.printStackTrace();
                }
            }
        }
        return "success";
    
    }

这就是springboot中文件的上传和下载，很简单很快捷