java实现文件下载

直接上代码：

    /*文件下载*/
    public static void downloadFile(HttpServletResponse response,String fileName,String path){
        if (fileName != null) {
            //设置文件路径
            File file = new File(path);
            if (file.exists()) {
                response.setHeader("content-type", "application/octet-stream");
                response.setContentType("application/octet-stream");
                try {
                    response.setHeader("Content-Disposition", "attachment;filename="+new String(fileName.getBytes("utf-8"),"ISO-8859-1"));
                } catch (UnsupportedEncodingException e) {
                    e.printStackTrace();
                }
                byte[] buffer = new byte[1024];
                FileInputStream fis = null;
                BufferedInputStream bis = null;
                try {
                    fis = new FileInputStream(file);
                    bis = new BufferedInputStream(fis);
                    OutputStream os = response.getOutputStream();
                    int i = bis.read(buffer);
                    while (i != -1) {
                        os.write(buffer, 0, i);
                        i = bis.read(buffer);
                    }
                } catch (Exception e) {
                    e.printStackTrace();
                } finally {
                    if (bis != null) {
                        try {
                            bis.close();
                        } catch (IOException e) {
                            e.printStackTrace();
                        }
                    }
                    if (fis != null) {
                        try {
                            fis.close();
                        } catch (IOException e) {
                            e.printStackTrace();
                        }
                    }
                }
            }
        }
    }