浏览器java文件下载判断IE,火狐，谷歌

 String agent = request.getHeader("User-Agent");
            boolean isMSIE = (agent != null && agent.indexOf("MSIE") != -1);
            //如果是IE的话
            if( isMSIE ){
            	System.out.println("IE");
            	codedFileName = java.net.URLEncoder.encode(codedFileName,"UTF8");
            }else{
            	System.out.println("不是IE");
            	codedFileName = new String(codedFileName.getBytes("UTF-8"), "ISO-8859-1");
            }