java.lang.IllegalStateException非法状态异常

java.lang.IllegalStateException: Illegal access: this web application instance has been stopped already. Could not load [org.apache.log4j.DailyRollingFileAppenderCustomizer]. The following stack trace is thrown for debugging purposes as well as to attempt to terminate the thread which caused the illegal access.

非法状态异常：非法访问：这个web应用程序实例已经被停止了。无法加载org.apache.log4j.DailyRollingFileAppenderCustomizer。为了调试目的，抛出了下面的堆栈跟踪，并尝试终止导致非法访问的线程。

项目中可能有一些残余的东西造成冲突。

解决办法：Tomcat >> clean操作>>Clean Tomcat Work Directory操作。