hutool实现文件上传与下载

        <dependency>
            <groupId>cn.hutoolgroupId>
            <artifactId>hutool-allartifactId>
            <version>5.8.16version>
        dependency>

文件上传需要创建一个表

@Autowired
    private SysFileInfoMapper sysFileInfoMapper;
 
    @Value("${ty.profile}")
    private String profile;
 
    @PostMapping("/add")
    public AjaxResult addSave( MultipartFile file, SysFileInfo fileInfo) throws IOException
    {
        //获取文件名2.txt
        String originalFilename = file.getOriginalFilename();
        //给文件名添加前缀年月日时分秒毫秒,防止文件名称重复给顶掉
        String fileName = DateUtils.parseDateToStr("yyyyMMddHHmmssSSS", DateUtils.getNowDate()) +"_"+ originalFilename;
        //获取文件路径,主路径+文件名
        String path = profile+"/"+fileName;
        //使用huTool工具类实现文件上传
        FileUtil.writeBytes(file.getBytes(),path);
        //将文件名和文件路径存入表中
        fileInfo.setFileName(fileName);
        fileInfo.setFilePath(path);
        sysFileInfoMapper.insert(fileInfo);
        return AjaxResult.success("成功");
    }
 
 
    /**
     * 本地资源通用下载
     */
    @GetMapping("/common/download/resources")
    public void resourceDownload(String resource, HttpServletRequest request, HttpServletResponse response)
            throws Exception
    {
        try {
            ServletOutputStream outputStream = response.getOutputStream();
            //根据文件名称查询文件路径
            LambdaQueryWrapper lambdaQueryWrapper = new LambdaQueryWrapper<>();
            lambdaQueryWrapper.eq(SysFileInfo::getFileName,resource);
            SysFileInfo sysFileInfo = sysFileInfoMapper.selectOne(lambdaQueryWrapper);
            if (ObjectUtil.isNotNull(sysFileInfo)){
                String filePath = sysFileInfo.getFilePath();
                response.setCharacterEncoding("utf-8");
                response.addHeader("Content-Disposition", "attachment;filename=" + URLEncoder.encode(sysFileInfo.getFileName(), "UTF-8"));
                response.setContentType("application/octet-stream");
                //通过文件的路径读取文件字节流,通过response的输出流返回文件
                outputStream.write(FileUtil.readBytes(filePath));
                outputStream.flush();
                outputStream.close();
            }
        }catch (Exception e){
            throw new SecurityException("文件下载失败");
        }
    }
 
 
    //实现pdf预览
    @GetMapping("/getPdfView")
    public void pdf(HttpServletRequest request, HttpServletResponse response) {
        try {
            File file = new File("C:\\hzx\\uploadPath\\2023\\10\\12\\打车去高铁站发票_20231012112938A001.pdf");
            FileInputStream fileInputStream = new FileInputStream(file);
            response.setHeader("Content-Type", "application/pdf");
            OutputStream outputStream = response.getOutputStream();
            IOUtils.write(IOUtils.toByteArray(fileInputStream), outputStream);
        } catch(Exception e) {
            e.printStackTrace();
        }
    }