一個Download.jsp檔案 （採用檔案流讀寫方式。可以防止doc.excl等檔案開啟時亂碼問題）

<%
 java.io.BufferedInputStream bis=null;
  java.io.BufferedOutputStream  bos=null;
try{
 String filename=request.getParameter("filename");
 response.setContentType("application/x-msdownload");
 response.setHeader("Content-disposition","attachment; filename="+filename);
 //request.getRealPath("Downloads/" + filename)
 bis =new java.io.BufferedInputStream(new FileInputStream(config.getServletContext().getRealPath("Downloads/" + filename)));
 bos=new java.io.BufferedOutputStream(response.getOutputStream()); 
 byte[] buff = new byte[2048];
 int bytesRead;
 while(-1 != (bytesRead = bis.read(buff, 0, buff.length))) {
  bos.write(buff,0,bytesRead);
 }
}
catch(Exception e){
 e.printStackTrace();
}
finally {
 if (bis != null)bis.close();
 if (bos != null)bos.close();
}
%> 

///注意：filename傳遞檔案名稱的參數,檔案名稱暫不支援中文。