When I deploy my spring-boot war to tomcat and start tomcat, I saw this error message

Question

1.[localhost-startStop-1] org.apache.catalina.core.ContainerBase.addChildInternal ContainerBase.addChild: start: org.apache.catalina.LifecycleException: Failed to start component [StandardEngine[Catalina].StandardHost[localhost].StandardContext[/lab]]

2.LoggerFactory is not a Logback LoggerContext but Logback is on the classpath. Either remove Logback or the competing implementation (class org.slf4j.impl.Log4jLoggerFactory loaded from file:/Users/zhangzhikai/apache-tomcat-8.0.53/webapps/lab/WEB-INF/lib/slf4j-log4j12-1.7.25.jar). If you are using WebLogic you will need to add 'org.slf4j' to prefer-application-packages in WEB-INF/weblogic.xml: org.slf4j.impl.Log4jLoggerFactory

3.org.apache.catalina.startup.HostConfig.deployWAR Error deploying web application archive /Users/zhangzhikai/apache-tomcat-8.0.53/webapps/lab.war java.lang.IllegalStateException: ContainerBase.addChild: start: org.apache.catalina.LifecycleException: Failed to start component [StandardEngine[Catalina].StandardHost[localhost].StandardContext[/lab]]

Answer 1

The problem looks like you have a dependency conflict between sl4j from tomcat and the one from spring-boot bundle.

Try to exlcude it from the dependecy Disable Logback in SpringBoot

Or make tha jar/war as a ubar, read this article if fits your scope:

https://docs.spring.io/spring-boot/docs/current/reference/html/getting-started-first-application.html Section talking about uber jar "11.5 Creating an Executable Jar"