responseEntity 实现文件下载

    @RequestMapping("/testResponseEntity")
    public ResponseEntity<byte[]> testResponseEntity(HttpSession session) throws IOException{
        byte [] body = null;
        ServletContext servletContext = session.getServletContext();
        InputStream in = servletContext.getResourceAsStream("/files/abc.txt");
        body = new byte[in.available()];
        in.read(body);

        HttpHeaders headers = new HttpHeaders();
        headers.add("Content-Disposition", "attachment;filename=abc.txt");

        HttpStatus statusCode = HttpStatus.OK;

        ResponseEntity<byte[]> response = new ResponseEntity<byte[]>(body, headers, statusCode);
        return response;
    }

<a href="testResponseEntity">Test ResponseEntity</a>