配置字符过滤器中<async-supported>报错异常
解决方案：
xmlns中再加两行
http://www.springmodules.org/schema/cache/springmodules-cache.xsd
http://www.springmodules.org/schema/cache/springmodules-ehcache.xsd
如：
<?xml version="1.0" encoding="UTF-8"?>
<web-app xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xmlns="http://java.sun.com/xml/ns/javaee
http://www.springmodules.org/schema/cache/springmodules-cache.xsd
http://www.springmodules.org/schema/cache/springmodules-ehcache.xsd"
xsi:schemaLocation="http://java.sun.com/xml/ns/javaee
http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd" id="WebApp_ID" version="2.5">
来源：https://www.cnblogs.com/cwb292/p/9956905.html