ie browser download attachment Chinese garbled

String llq = request.getHeader( "USER-AGENT" ).toLowerCase();
Boolean isIE = false;
if (llq.indexOf("msie") > -1 || llq.indexOf("rv:11") > -1) {
   isIE = true;
}
if(isIE) {
   fileName = URLEncoder.encode(fileName, "UTF-8");       //ie用这个
}else{
   fileName = new String(fileName.getBytes("UTF-8"), "ISO8859-1");  //不是ie用这个
}
response.setHeader("Content-disposition", "attachment; filename="
      + fileName);