Error assembling WAR: webxml attribute is required (or pre-existing WEB-INF/web.xml if executing in

Error assembling WAR: webxml attribute is required (or pre-existing WEB-INF/web.xml if executing in update mode) 

打包方式为WAR时 在webapp 下 缺少 WEB-INF/web.xml

<?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" xmlns:web="http://java.sun.com/xml/ns/javaee/web-app_2_5.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">
<display-name>taotao-manager-web</display-name>
<welcome-file-list>
<welcome-file>index.jsp</welcome-file>

</welcome-file-list>

</web-app>