从服务器使用IO流下载文件，部分类型文件下载后内容出错

公司的门户网站需要实现文件上传下载功能。
在实现下载功能后，测试txt文件，下载成功。但是doc和图片等文件下载后，出现内容缺失问题。
以下为下载功能代码：

public class LayUiDownload  extends HttpServlet {


    /**
     * Constructor of the object.
     */
    public LayUiDownload() {
        super();
    }

    /**
     * Destruction of the servlet. <br>
     */
    public void destroy() {
        super.destroy(); // Just puts "destroy" string in log
        // Put your code here
    }

    public void doGet(HttpServletRequest request, HttpServletResponse response)
            throws ServletException, IOException {

        this.doPost(request, response);
    }

    public synchronized void doPost(HttpServletRequest request,
        HttpServletResponse response) throws ServletException, IOException {

        String params=request.getParameter("params");
        //Map<String, String[]>maps =  request.getParameterMap();
        String URL=params.substring(8,params.lastIndexOf("\""));            
        //URL=URL.replace("\\\\", "/");
        String ori_url=URL;
        String URL0=URL.substring(0,URL.lastIndexOf("/")+1);
        String URL1=URL.substring(URL.lastIndexOf("/")+1);
        URL1 = URLEncoder.encode(URL1, "UTF-8");
        URL=URL0+URL1;
        File file = null;
        try {      
            // 统一资源           
                String    urlPath =URL;
            // 统一资源
            URL url = new URL(urlPath);
            // 连接类的父类，抽象类
            URLConnection urlConnection = url.openConnection();
            // http的连接类
            HttpURLConnection httpURLConnection = (HttpURLConnection) urlConnection;
            //设置超时
            httpURLConnection.setConnectTimeout(1000*5);
            //设置请求方式，默认是GET
            httpURLConnection.setRequestMethod("POST");
            // 设置字符编码

            httpURLConnection.setRequestProperty("Charset", "UTF-8");
            httpURLConnection.connect();
            int fileLength = httpURLConnection.getContentLength();

            BufferedInputStream bin = new BufferedInputStream(httpURLConnection.getInputStream());
            String fileFullName = ori_url.substring(ori_url.lastIndexOf("/")+1);
            // 指定存放位置
            String path = "D:\\Program Files\\file" + File.separatorChar + fileFullName;
            file = new File(path);
            // 校验文件夹目录是否存在，不存在就创建一个目录
            if (!file.getParentFile().exists()) {
                file.getParentFile().mkdirs();
            }
            OutputStream out = new FileOutputStream(file);
            int size = 0;
            int len = 0;
            byte[] buf = new byte[2048];
            while ((size = bin.read(buf)) != -1) {
                len += size;
                out.write(buf, 0, size);
                System.out.println("下载了-------> " + len * 100 / fileLength + "%\n");
            }
            System.out.println("C:"+ File.separatorChar + urlPath.substring(urlPath.lastIndexOf("/")).split("/")[1]);
            bin.close();
            out.close();
            System.out.println("文件下载成功！");
        } catch (Exception e) {
            System.out.println("文件下载失败！");
            e.printStackTrace();
        }finally {![图片说明](https://img-ask.csdn.net/upload/202001/02/1577952059_62148.png)

            System.out.println("文件下载结束！");        
        }   
    }
}

截图：
上传的正常文件：

下载的问题文件：

下载的问题图片文件:

问题已解决，原因是配置中对资源的访问只有TXT类型做了配置，其他类型文件的下载请求都被登录界面拦截了，多谢回答

out.flush()试试

试试
直接用 httpURLConnection.getInputStream()
不要用 new BufferedInputStream