第六阶段 第四模块

` public ResponseResult fileUpload(@RequestParam("file")MultipartFile file, HttpServletRequest request) throws IOException {

    //1.判断接收到的上传文件是否为空
    if(file.isEmpty()){
        throw  new RuntimeException();
    }

    //2.获取项目部署路径

    // D:\apache-tomcat-8.5.56\webapps\ssm-web\
    String realPath = request.getServletContext().getRealPath("/");
    // D:\apache-tomcat-8.5.56\webapps
    String substring = realPath.substring(0, realPath.indexOf("ssm-web"));



    //3.获取原文件名
    //lagou.jpg
    String originalFilename = file.getOriginalFilename();

    //4.生成新文件名
    //12421321.jpg
    String newFileName = System.currentTimeMillis() + originalFilename.substring(originalFilename.lastIndexOf("."));

    //5.文件上传

    String uploadPath = substring + "upload\\";
    File filePath = new File(uploadPath, newFileName);

    // 如果目录不存在就创建目录
    if(!filePath.getParentFile().exists()){
        filePath.getParentFile().mkdirs();
        System.out.println("创建目录：" + filePath);
    }

    // 图片就进行了真正的上传
    file.transferTo(filePath);

    // 6. 将文件名和文件路径返回，进行响应
    Map<String, String> map = new HashMap<>();
    map.put("fileName",newFileName);

    map.put("filePath","http://localhost:8080/upload/" + newFileName);

    ResponseResult responseResult = new ResponseResult(true, 200, "图片上传成功", map);

    return responseResult;

}`