上传multipart文件

@PostMapping(path = "/upload", consumes = {MediaType.APPLICATION_FORM_URLENCODED_VALUE, MediaType.MULTIPART_FORM_DATA_VALUE}, produces = MediaType.MULTIPART_FORM_DATA_VALUE)
@ApiOperation(value = "学生端/教师端log文件上传local server")
public String receive(@RequestParam(value = "file") @ApiParam(value = "log文件") MultipartFile file,
                      @RequestParam(value = "cmdId") @ApiParam(value = "主机命令id") String cmdId) throws IOException {
    String separator = File.separator;
    String path = fileSystemUtils.getTmpPath() + separator + file.getOriginalFilename();
    if (!file.isEmpty()) {
        try {
            BufferedOutputStream out = new BufferedOutputStream(
                    new FileOutputStream(new File(path)));
            out.write(file.getBytes());
            out.flush();
            out.close();
        } catch (Exception ex) {
            ex.printStackTrace();
            return "fail," + ex.getMessage();
        }
        // oss log 下载地址
        String ossLogURL = logbackService.postFile(path, cmdId);
        if (ossLogURL != null) {
            heartbeatService.postResponse(cmdId, ossLogURL, "FULFILLED");
        } else {
            log.error("upload log to oss fail");
            heartbeatService.postResponse(cmdId, "upload fail", "REJECTED");
        }
        return "upload success.";
    } else {
        return "error,empty file.";
    }
}