以下是重要的几个报错节点
20-Aug-2019 12:01:19.909 严重 [Catalina-startStop-1] org.apache.catalina.core.ContainerBase.startInternal A child container failed during start Caused by: org.apache.catalina.LifecycleException: Failed to start component [StandardEngine[Catalina].StandardHost[localhost].StandardContext[/demo]] Caused by: java.lang.IllegalArgumentException: More than one fragment with the name [spring_web] was found. This is not legal with relative ordering. See section 8.2.2 2c of the Servlet specification for details. Consider using absolute ordering.
经查原因是：
在D:\apache-tomcat-8.5.42-windows-x64\webapps\项目名\WEB-INF\lib 下
有两个版本的 spring-web.jar包 删除一个版本，留存了一个版本之后，问题解决、
