public void doGet(HttpServletRequest request, HttpServletResponse response)
            throws ServletException, IOException {
        String aFilePath = null;    //要下载的文件路径
        String aFileName = null;    //要下载的文件名
        response.setHeader("pragma","no-cache");   
        response.setHeader("cache-control","no-cache"); 
        response.setDateHeader("Expires",0);   
        
        request.setCharacterEncoding("GBK");
        try
        {
            
            String str = getServletContext().getRealPath("/");
            str = str.replaceAll("\\\\", "/");// 转换\为/;
            
            String temp_name = request.getParameter("name");//取文件实际路径和名称
            String title = request.getParameter("jc");//取下载文件的名称
            String temp_1 = temp_name.substring(temp_name.lastIndexOf("."));//取扩展名
            aFilePath = str; 
            aFileName = temp_name.substring(temp_name.lastIndexOf("/")+1);
            //碰到title中有.的，取最后一个.的前面部分作为title
            if(title.lastIndexOf(".")!= -1)title = title.substring(0,title.lastIndexOf("."));
            
            
            
            String abc = title+temp_1;
            String newsName = java.net.URLDecoder.decode(abc,"GBK");

            response.setContentType("text/x-msdownload");
             //response.addHeader("Content-Disposition","attachment; filename=\"" + new String(abc.getBytes("GBK"),"utf-8") + "\"");
            response.addHeader("Content-Disposition","attachment; filename=\"" + new String(newsName.getBytes(),"ISO-8859-1") + "\"");
            java.io.OutputStream os = null;
            java.io.FileInputStream fis = null;
            try {
                os = response.getOutputStream();
                fis = new java.io.FileInputStream(aFilePath + temp_name);
                byte[] b = new byte[1024];
                int j = 0;
                while ((j = fis.read(b)) > 0) {
                    os.write(b, 0, j);
                }
                fis.close();
                os.flush();//报错信息指向了这行
                os.close();
            } catch (Exception e) {
                e.printStackTrace();
            }
            ///
            
     }
      catch(Throwable e)
    {
    //log.error("FileDownload doGet() IO error!",e);
     }
        
    }