Spring mvc 自带的以流形式提供下载方法

/**
*资源下载
**/
@RequestMapping("/download")
public ResponseEntity<byte[]> download(String scienceId,HttpServletRequest request) throws IOException{
File file = null;
String fileName = "";
try{
String path = request.getSession().getServletContext().getRealPath("/upload/science/"+scienceId);
TScienceStudy scienceStudy = scienceStudyService.findOne(Long.valueOf(scienceId));
String str = scienceStudy.getArticleUrl();
path = path +str.substring(str.lastIndexOf("/"));
file = new File(path);
HttpHeaders headers = new HttpHeaders();
fileName = new String(scienceStudy.getFileName().getBytes("UTF-8"),"iso-8859-1");
headers.setContentDispositionFormData("attachment", fileName);
headers.setContentType(MediaType.APPLICATION_OCTET_STREAM);
return new ResponseEntity<byte[]>(FileUtils.readFileToByteArray(file),headers,HttpStatus.OK);
}catch(Exception e){
e.printStackTrace();
}
return null;
}