tomcat 日志log4j，slf4j,logback冲突

5643

问题描述：

        启动tomcat，发现tomcat无法启动，catalina.out有如下错误日志：

INFO [localhost-startStop-1]org.apache.catalina.core.ApplicationContext.log Closing Spring rootWebApplicationContext

SEVERE [localhost-startStop-1]org.apache.catalina.core.StandardContext.listenerStop Exception sending contextdestroyed event to listener instance of classorg.springframework.web.context.ContextLoaderListener

java.lang.NoClassDefFoundError: Could notinitialize class org.apache.log4j.Log4jLoggerFactory

        atorg.apache.log4j.LogManager.getLogger(LogManager.java:44)

        atorg.slf4j.impl.Log4jLoggerFactory.getLogger(Log4jLoggerFactory.java:73)

        atorg.slf4j.LoggerFactory.getLogger(LoggerFactory.java:270)

        atorg.apache.commons.logging.impl.SLF4JLogFactory.getInstance(SLF4JLogFactory.java:156)

        atorg.apache.commons.logging.impl.SLF4JLogFactory.getInstance(SLF4JLogFactory.java:132)

        atorg.apache.commons.logging.LogFactory.getLog(LogFactory.java:274)

        atorg.springframework.web.context.ContextCleanupListener.<clinit>(ContextCleanupListener.java:43)

        atorg.springframework.web.context.ContextLoaderListener.contextDestroyed(ContextLoaderListener.java:145)

        atorg.apache.catalina.core.StandardContext.listenerStop(StandardContext.java:4860)

        atorg.apache.catalina.core.StandardContext.stopInternal(StandardContext.java:5495)

        atorg.apache.catalina.util.LifecycleBase.stop(LifecycleBase.java:224)

        atorg.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:159)

        atorg.apache.catalina.core.ContainerBase$StartChild.call(ContainerBase.java:1407)

        atorg.apache.catalina.core.ContainerBase$StartChild.call(ContainerBase.java:1397)

        atjava.util.concurrent.FutureTask.run(FutureTask.java:266)

        atjava.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142)

        atjava.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)

        atjava.lang.Thread.run(Thread.java:745)

问题分析：

    检查lib库下面，发现今天更新过log4j和logback组合，总共有如下包：

slf4j-api-1.7.5.jar

slf4j-log4j12-1.6.1.jar

log4j-1.2.16.jar

log4j-over-slf4j-1.7.5.jar

logback-core-1.1.2.jar

logback-classic-1.1.2.jar

    通过查询资料发现，包slf4j-log4j12-1.6.1.jar  和log4j有冲突。

解决方法：

      删除后正常，删除这个：slf4j-log4j12-1.6.1.jar  

附件常见组合：

log4j+slf4j

slf4j-api-1.7.5.jar
slf4j-log4j12-1.6.1.jar
log4j-1.2.16.jar

slf4j+logback

logback-core-1.1.2.jar
logback-classic-1.1.2.jar
slf4j-api-1.7.5.jar