springboot文件上传下载示例代码

以下是 Spring Boot 文件上传下载的示例代码：

文件上传：

@PostMapping("/upload")
public String uploadFile(@RequestParam("file") MultipartFile file) {
    try {
        // 获取文件名
        String fileName = file.getOriginalFilename();
        // 获取文件的字节数组
        byte[] bytes = file.getBytes();
        // 保存文件
        Path path = Paths.get("uploads/" + fileName);
        Files.write(path, bytes);
        return "文件上传成功！";
    } catch (IOException e) {
        e.printStackTrace();
        return "文件上传失败！";
    }
}

文件下载：

@GetMapping("/download")
public ResponseEntity<Resource> downloadFile(@RequestParam("fileName") String fileName) {
    try {
        // 加载文件资源
        Path path = Paths.get("uploads/" + fileName);
        Resource resource = new UrlResource(path.toUri());
        // 设置响应头
        HttpHeaders headers = new HttpHeaders();
        headers.add(HttpHeaders.CONTENT_DISPOSITION, "attachment; filename=" + fileName);
        // 返回文件资源
        return ResponseEntity.ok()
                .headers(headers)
                .contentLength(resource.contentLength())
                .contentType(MediaType.APPLICATION_OCTET_STREAM)
                .body(resource);
    } catch (MalformedURLException e) {
        e.printStackTrace();
        return ResponseEntity.notFound().build();
    } catch (IOException e) {
        e.printStackTrace();
        return ResponseEntity.status(HttpStatus.INTERNAL_SERVER_ERROR).build();
    }
}