Unable to load configuration. -
file:/E:/IDEA/IntelliJ%20IDEA%202021.2.2/J2EE/out/artifacts/J2EE_war_exploded/WEB-INF/classes/struts.xml:3:8

此时xml文件内容

报错如下

添加下列语句即可，这里是struts2.5

<!DOCTYPE struts PUBLIC
        "-//Apache Software Foundation//DTD Struts Configuration 2.5//EN"
        "http://struts.apache.org/dtds/struts-2.5.dtd">