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프로젝트 회사 플랫폼 버전 업데이트 및 리팩토링 중 오류가 발생했습니다.

Legacy Project를 리팩토링을 하다보니 많은 것을 수정해야 했고, 당연하게도 오류를 마주했습니다.. :-(

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에러로그

심각: A child container failed during start
java.util.concurrent.ExecutionException: org.apache.catalina.LifecycleException: Failed to start component [StandardEngine[Catalina].StandardHost[localhost].StandardContext[/spring-web]]
	at java.util.concurrent.FutureTask.report(FutureTask.java:122)
	at java.util.concurrent.FutureTask.get(FutureTask.java:192)
	at org.apache.catalina.core.ContainerBase.startInternal(ContainerBase.java:1123)
	at org.apache.catalina.core.StandardHost.startInternal(StandardHost.java:800)
	at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:150)
	at org.apache.catalina.core.ContainerBase$StartChild.call(ContainerBase.java:1559)
	at org.apache.catalina.core.ContainerBase$StartChild.call(ContainerBase.java:1549)
	at java.util.concurrent.FutureTask.run(FutureTask.java:266)
	at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149)
	at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624)
	at java.lang.Thread.run(Thread.java:748)
Caused by: org.apache.catalina.LifecycleException: Failed to start component [StandardEngine[Catalina].StandardHost[localhost].StandardContext[/spring-web]]
	at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:154)
	... 6 more
Caused by: java.lang.NoClassDefFoundError: ch/qos/logback/core/joran/spi/JoranException
	at java.lang.Class.getDeclaredFields0(Native Method)
	at java.lang.Class.privateGetDeclaredFields(Class.java:2583)
	at java.lang.Class.getDeclaredFields(Class.java:1916)
	at org.apache.catalina.util.Introspection.getDeclaredFields(Introspection.java:106)
	at org.apache.catalina.startup.WebAnnotationSet.loadFieldsAnnotation(WebAnnotationSet.java:263)
	at org.apache.catalina.startup.WebAnnotationSet.loadApplicationListenerAnnotations(WebAnnotationSet.java:92)
	at org.apache.catalina.startup.WebAnnotationSet.loadApplicationAnnotations(WebAnnotationSet.java:65)
	at org.apache.catalina.startup.ContextConfig.applicationAnnotationsConfig(ContextConfig.java:405)
	at org.apache.catalina.startup.ContextConfig.configureStart(ContextConfig.java:881)
	at org.apache.catalina.startup.ContextConfig.lifecycleEvent(ContextConfig.java:376)
	at org.apache.catalina.util.LifecycleSupport.fireLifecycleEvent(LifecycleSupport.java:119)
	at org.apache.catalina.util.LifecycleBase.fireLifecycleEvent(LifecycleBase.java:90)
	at org.apache.catalina.core.StandardContext.startInternal(StandardContext.java:5322)
	at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:150)
	... 6 more
Caused by: java.lang.ClassNotFoundException: ch.qos.logback.core.joran.spi.JoranException
	at org.apache.catalina.loader.WebappClassLoader.loadClass(WebappClassLoader.java:1702)
	at org.apache.catalina.loader.WebappClassLoader.loadClass(WebappClassLoader.java:1547)
	... 20 more

11월 02, 2022 4:32:06 오후 org.apache.catalina.core.ContainerBase startInternal
심각: A child container failed during start
java.util.concurrent.ExecutionException: org.apache.catalina.LifecycleException: Failed to start component [StandardEngine[Catalina].StandardHost[localhost]]
	at java.util.concurrent.FutureTask.report(FutureTask.java:122)
	at java.util.concurrent.FutureTask.get(FutureTask.java:192)
	at org.apache.catalina.core.ContainerBase.startInternal(ContainerBase.java:1123)
	at org.apache.catalina.core.StandardEngine.startInternal(StandardEngine.java:302)
	at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:150)
	at org.apache.catalina.core.StandardService.startInternal(StandardService.java:443)
	at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:150)
	at org.apache.catalina.core.StandardServer.startInternal(StandardServer.java:732)
	at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:150)
	at org.apache.catalina.startup.Catalina.start(Catalina.java:691)
	at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
	at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
	at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
	at java.lang.reflect.Method.invoke(Method.java:498)
	at org.apache.catalina.startup.Bootstrap.start(Bootstrap.java:322)
	at org.apache.catalina.startup.Bootstrap.main(Bootstrap.java:456)
Caused by: org.apache.catalina.LifecycleException: Failed to start component [StandardEngine[Catalina].StandardHost[localhost]]
	at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:154)
	at org.apache.catalina.core.ContainerBase$StartChild.call(ContainerBase.java:1559)
	at org.apache.catalina.core.ContainerBase$StartChild.call(ContainerBase.java:1549)
	at java.util.concurrent.FutureTask.run(FutureTask.java:266)
	at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149)
	at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624)
	at java.lang.Thread.run(Thread.java:748)
Caused by: org.apache.catalina.LifecycleException: A child container failed during start
	at org.apache.catalina.core.ContainerBase.startInternal(ContainerBase.java:1131)
	at org.apache.catalina.core.StandardHost.startInternal(StandardHost.java:800)
	at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:150)
	... 6 more

11월 02, 2022 4:32:06 오후 org.apache.catalina.startup.Catalina start
심각: The required Server component failed to start so Tomcat is unable to start.
org.apache.catalina.LifecycleException: Failed to start component [StandardServer[8005]]
	at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:154)
	at org.apache.catalina.startup.Catalina.start(Catalina.java:691)
	at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
	at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
	at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
	at java.lang.reflect.Method.invoke(Method.java:498)
	at org.apache.catalina.startup.Bootstrap.start(Bootstrap.java:322)
	at org.apache.catalina.startup.Bootstrap.main(Bootstrap.java:456)
Caused by: org.apache.catalina.LifecycleException: Failed to start component [StandardService[Catalina]]
	at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:154)
	at org.apache.catalina.core.StandardServer.startInternal(StandardServer.java:732)
	at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:150)
	... 7 more
Caused by: org.apache.catalina.LifecycleException: Failed to start component [StandardEngine[Catalina]]
	at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:154)
	at org.apache.catalina.core.StandardService.startInternal(StandardService.java:443)
	at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:150)
	... 9 more
Caused by: org.apache.catalina.LifecycleException: A child container failed during start
	at org.apache.catalina.core.ContainerBase.startInternal(ContainerBase.java:1131)
	at org.apache.catalina.core.StandardEngine.startInternal(StandardEngine.java:302)
	at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:150)
	... 11 more

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분석

에러 로그를 확인해보면,
1. org.apache.catalina.LifecycleException: Failed to start component
2. Caused by: java.lang.NoClassDefFoundError: ch/qos/logback/core/joran/spi/JoranException

주된 내용은 Tomcat을 실행할 수 없으며, JoranException.class를 찾을 수 없다고 나옵니다.

그러나 JoranException.class를 검색했을 때 실제로 검색이됩니다.
Q) 그렇다면 문제는 무엇일까요..?

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해결

org.apache.catalina.LifecycleException:
...
java.lang.NoClassDefFoundError
...

위와 같은 오류가 발생하게 된다면, 아래 2가지를 확인!

1. Maven Project의 경우, Maven Repository를 확인
2. Library를 사용할 경우, Deployment Assembly를 확인

저는 userLibrary를 추가하지 않아 오류가 발생했습니다.(😅)

플랫폼 버전을 업데이트하면서 library의 버전을 올린 후 추가하지 않았습니다.. 이런 실수를..😂

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1. 오류가 발생해도 침착하게 로그를 확인!
2. 오류는 그냥 발생하지 않으니까.. 이유는 분명히있다!