参考地址

springboot：各种下载文件的方式_springboot下载文件-CSDN博客

开箱即用实战

 @GetMapping("/t1")public void down1(HttpServletResponse response) throws Exception {response.reset();response.setContentType("application/octet-stream;charset=utf-8");response.setHeader("Content-disposition","attachment; filename=test.png");try(BufferedInputStream bis = new BufferedInputStream(new FileInputStream("C:\\Users\\Harbor\\Pictures\\Camera Roll\\111.jpg"));// 输出流BufferedOutputStream bos = new BufferedOutputStream(response.getOutputStream());){byte[] buff = new byte[1024];int len = 0;while ((len = bis.read(buff)) > 0) {bos.write(buff, 0, len);}}}