java文件下载时文件名在ie和firefox下面表现不一致问题

首先文件名是是以utf-8编码保存在数据库中，文件名暂定为1_中文文件123.txt，然后作如下处理来下载
response.setContentType("application/octet-stream;charset=UTF-8");
fileName=java.net.URLEncoder.encode(fileName, "UTF-8");
response.setHeader("Content-Disposition", "attachment; filename=" + fileName);
此时在ie下面点击文件下载的时候能够正确显示中文名称1_中文文件123.txt%0A，但是文件名的结尾却出现%0A字符（个人猜测是结束符的utf-8编码）；但是此时在firefox下面却显示1_%E4%B8%AD%E6%96%87%E6%96%87%E4%BB%B6123.txt%0A
然后我又试了另一种方案
response.setContentType("application/octet-stream;charset=UTF-8");
fileName = new String(fileName.getBytes("UTF-8"),"iso-8859-1");
response.setHeader("Content-Disposition", "attachment; filename=" + fileName);
此时在ie下面下载的时候弹chu的文件名是乱码；而在firefox下面却正确显示1_中文文件123.txt。

解决方案：
public String getFileName(String filename, HttpServletRequestWrapper reqw){
        String agent = reqw.getHeader("USER-AGENT");
        if(null != agent && -1 != agent.indexOf("MSIE")){
            filename = URLEncoder.encode(filename,"UTF8");
        }else if(null != agent && -1 != agent.indexOf("Mozilla")){
            filename = MimeUtility.encodeText(filename,"UTF8","B");
        }
        return filename;

}