Referenced file contains errors (http://java.sun.com/xml/ns/javaee/web-app_3_1.xsd)

1、错误描述

Maven项目 web.xml 头部报错

'Description	Resource	Path	Location	Type
Referenced file contains errors (http://java.sun.com/xml/ns/javaee/web-app_3_1.xsd).  For more information, right click on the message in the Problems View and select "Show         
Details..."	web.xml	/testweba/src/main/webapp/WEB-INF	line 1	XML Problem

'

我修改后正确的头部

<web-app xmlns="http://xmlns.jcp.org/xml/ns/javaee"
         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
         xsi:schemaLocation="http://xmlns.jcp.org/xml/ns/javaee 
         http://xmlns.jcp.org/xml/ns/javaee/web-app_3_1.xsd"
         version="3.1">

参考：

https://stackoverflow.com/questions/32538754/eclipse-web-xml-referenced-file-error