Java下载文件中文文件名乱码的解决方案(文件名包含很多%)

fileName = URLEncoder.encode(fileName, "UTF-8");
response.reset();
response.setHeader("Content-disposition", "attachment;filename=" + fileName);
response.setContentType("application/octet-stream; charset=UTF-8");
IoUtil.copy(inputStream, response.getOutputStream());

String downloadfile = new String(filepath.getBytes("gb2312"),"iso8859-1");
response.addHeader("Content-Disposition","attachment;filename=" + downloadfile );

String userAgent = request.getHeader("User-Agent");
String formFileName = "员工表.xls";

// 针对IE或者以IE为内核的浏览器：
if (userAgent.contains("MSIE") || userAgent.contains("Trident")) {
formFileName = java.net.URLEncoder.encode(formFileName, "UTF-8");
} else {
// 非IE浏览器的处理：
formFileName = new String(formFileName.getBytes("UTF-8"), "ISO-8859-1");
}
response.setHeader("Content-disposition",String.format("attachment; filename=\"%s\"", formFileName));
response.setContentType("multipart/form-data");
response.setCharacterEncoding("UTF-8")；

fileName = URLEncoder.encode(fileName, "UTF-8");
response.reset();
// fileName后面设置编码格式是重点
response.setHeader("Content-disposition", "attachment;filename="+fileName+";"+"filename*=utf-8''"+fileName);
response.setContentType("application/octet-stream; charset=UTF-8");
IoUtil.copy(inputStream, response.getOutputStream());