web.xml 报错The content of element type "web-app" must match

web.xml 报错The content of element type “web-app” must match

错误：The content of element type “web-app” must match “(icon?,display-

name?,description?,distributable?,context-param*,filter*,filter-mapping*,listener*,servlet*,servlet-

mapping*,session-config?,mime-mapping*,welcome-file-list?,error-page*,taglib*,resource-env-

ref*,resource-ref*,security-constraint*,login-config?,security-role*,env-entry*,ejb-ref*,ejb-local-ref*)”.

- No grammar constraints (DTD or XML schema) detected for the document.

web.xml头部配置：