@RequestMapping(value = "/upload")

    public ResponseEntity<byte[]> upload() throws IOException{

        File file=new File("G:\\e盘\\恒之工作室\\书\\zxc.pdf");

        HttpHeaders headers = new HttpHeaders();

        String fileName=new String("zxc.pdf".getBytes("UTF-8"),"iso-8859-1");//为了解决中文名称乱码问题

        headers.setContentDispositionFormData("attachment", fileName);

        headers.setContentType(MediaType.APPLICATION_OCTET_STREAM);

        return new ResponseEntity<byte[]>(FileUtils.readFileToByteArray(file), headers, HttpStatus.CREATED);

    }