web.xml的新配置

<?xml version="1.0" encoding="UTF-8"?>

<web-app metadata-complete="true" version="4.0" xsi:schemaLocation="http://xmlns.jcp.org/xml/ns/javaee http://xmlns.jcp.org/xml/ns/javaee/web-app_4_0.xsd" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns="http://xmlns.jcp.org/xml/ns/javaee">

  <display-name>Welcome to Tomcat</display-name>
  <description>Welcome to Tomcat </description>
  
</web-app>