SpringMVC文件下载

@RequestMapping("download")
 public ResponseEntity<byte[]> fileDownload(String fileName) throws UnsupportedEncodingException {
     File file = new File("D:\\Program Files\\Java\\jar\\spring\\spring-framework-5.1.9.RELEASE-dist\\spring-framework-5.1.9.RELEASE\\libs\\jar", fileName);
HttpHeaders headers = new HttpHeaders();
     //设置响应头信息类型
     headers.setContentType(MediaType.APPLICATION_OCTET_STREAM);
     //new String(fileName.getBytes("UTF-8"), "iso-8859-1")头信息如果不经过转码，中文文件名会变成下划线
     headers.setContentDispositionFormData("attachment", new String(fileName.getBytes("UTF-8"), "iso-8859-1"));
     ResponseEntity<byte[]> responseEntity = null;
     try {
         //将文件转换为字节流并返回
         responseEntity = new ResponseEntity<>(FileUtils.readFileToByteArray(file), headers, HttpStatus.OK);
     } catch (IOException e) {
         e.printStackTrace();
     }

     return responseEntity;
 }