Referenced file contains errors (HTTP://STRUTS.APACHE.ORG/DTDS/STRUTS-2.3.DTD)

Since the start of Tomcat this morning, it's been a mistake.

Yesterday when the time is still good, I really do not understand AH

Look, my struts is 2.1, and then I modified the Struts.xml reference to the DTD

<?xml version= "1.0" encoding= "UTF-8"?>
<! DOCTYPE struts Public "-//apache Software foundation//dtd struts Configuration 2.0//en" "http://struts.apache.org/dtds/ Struts-2.0.dtd ">

And it turns out to be the wrong one.

Then I looked at the error and I found my jar pack version was wrong

Modify the struts2-spring-plugin-2.3.4.1 to struts2-spring-plugin-2.1.8.1

Problem solving O (∩_∩) o~

I don't know if this is your problem.

But I still do not understand, why yesterday can, today can not be ...