经过我测试除了文件名称包含英文逗号谷歌会下载失败外，其它的都没问题了。这个找到解决方法了再补上，先记录一下

String userAgent = request.getHeader("user-agent").toLowerCase();

if (userAgent.contains("msie")) {// IE

try {

fileName = URLEncoder.encode(fileName, "UTF-8").replaceAll("%20", "\\+").replaceAll("%28", "\\(")

.replaceAll("%29", "\\)").replaceAll("%3B", ";").replaceAll("%40", "@").replaceAll("%23", "\\#")

.replaceAll("%26", "\\&").replaceAll("%2C", "\\,").replaceAll("%24", "\\$")

.replaceAll("%25", "\\%").replaceAll("%5E", "\\^").replaceAll("%3D", "\\=")

.replaceAll("%2B", "\\+");

} catch (UnsupportedEncodingException e) {

e.printStackTrace();

}

response.setHeader("Content-Disposition", "attachment; filename=" + fileName);

} else if (userAgent.contains("like gecko")) {// 谷歌

try {

fileName = URLEncoder.encode(fileName, "UTF-8").replaceAll("%20", "\\+").replaceAll("%28", "\\(")

.replaceAll("%29", "\\)").replaceAll("%3B", ";").replaceAll("%40", "@").replaceAll("%23", "\\#")

.replaceAll("%26", "\\&").replaceAll("%2C", "\\,").replaceAll("%24", "\\$")

.replaceAll("%25", "\\%").replaceAll("%5E", "\\^").replaceAll("%3D", "\\=")

.replaceAll("%2B", "\\+").replaceAll("%5B", "\\[").replaceAll("%5D", "\\]")

.replaceAll("%7B", "\\{").replaceAll("%7D", "\\}");

} catch (UnsupportedEncodingException e) {

e.printStackTrace();

}

response.setHeader("Content-Disposition", "attachment; filename=" + fileName);

} else if (userAgent.contains("firefox")) {// 火狐

try {

fileName = new String(fileName.getBytes("UTF-8"), "ISO-8859-1").replaceAll("%20", "\\+")

.replaceAll("%28", "\\(").replaceAll("%29", "\\)").replaceAll("%3B", ";").replaceAll("%40", "@")

.replaceAll("%23", "\\#").replaceAll("%26", "\\&").replaceAll("%2C", "\\,")

.replaceAll("%24", "\\$");

} catch (UnsupportedEncodingException e) {

e.printStackTrace();

}

response.setHeader("Content-Disposition", "attachment;filename=\"" + fileName + "\"");

}