Java获取PDF文件流

@RequestMapping("/getPdf")
    public void showPdf(HttpServletResponse response, String path) {

        response.setContentType("application/pdf");
        FileInputStream in;
        OutputStream out;
        try {
            in = new FileInputStream(new File(path));
            out = response.getOutputStream();
            byte[] b = new byte[512];
            while ((in.read(b)) != -1) {
                out.write(b);
                out.flush();
            }
            in.close();
            out.close();

        } catch (Exception e) {
            e.printStackTrace();
        }
    }