今天进行maven 的多模块开发(以springboot为主)时，遇到了logback日志问题。异常如下：
Failed to instantiate [ch.qos.logback.classic.LoggerContext]
Reported exception:
java.lang.NoClassDefFoundError: org/slf4j/event/LoggingEvent
at java.lang.Class.getDeclaredMethods0(Native Method)
at java.lang.Class.privateGetDeclaredMethods(Class.java:2615)
at java.lang.Class.privateGetPublicMethods(Class.java:2733)
at java.lang.Class.getMethods(Class.java:1472)
at java.beans.Introspector.getPublicDeclaredMethods(Introspector.java:1280)
at java.beans.Introspector.getTargetMethodInfo(Introspector.java:1141)
at java.beans.Introspector.getBeanInfo(Introspector.java:416)
at java.beans.Introspector.getBeanInfo(Introspector.java:163)
at ch.qos.logback.core.joran.util.PropertySetter.introspect(PropertySetter.java:79)
at ch.qos.logback.core.joran.util.PropertySetter.getMethod(PropertySetter.java:393)
at ch.qos.logback.core.joran.util.PropertySetter.findAdderMethod(PropertySetter.java:203)
at ch.qos.logback.core.joran.util.PropertySetter.computeAggregationType(PropertySetter.java:177)
at ch.qos.logback.core.joran.action.NestedComplexPropertyIA.isApplicable(NestedComplexPropertyIA.java:61)
at ch.qos.logback.core.joran.spi.Interpreter.lookupImplicitAction(Interpreter.java:237)
at ch.qos.logback.core.joran.spi.Interpreter.getApplicableActionList(Interpreter.java:256)
at ch.qos.logback.core.joran.spi.Interpreter.startElement(Interpreter.java:144)
at ch.qos.logback.core.joran.spi.Interpreter.startElement(Interpreter.java:129)
at ch.qos.logback.core.joran.spi.EventPlayer.play(EventPlayer.java:50)
at ch.qos.logback.core.joran.GenericConfigurator.doConfigure(GenericConfigurator.java:149)
at ch.qos.logback.core.joran.GenericConfigurator.doConfigure(GenericConfigurator.java:135)
at ch.qos.logback.core.joran.GenericConfigurator.doConfigure(GenericConfigurator.java:99)
at ch.qos.logback.core.joran.GenericConfigurator.doConfigure(GenericConfigurator.java:49)
at ch.qos.logback.classic.util.ContextInitializer.configureByResource(ContextInitializer.java:77)
at ch.qos.logback.classic.util.ContextInitializer.autoConfig(ContextInitializer.java:152)
at org.slf4j.impl.StaticLoggerBinder.init(StaticLoggerBinder.java:85)
at org.slf4j.impl.StaticLoggerBinder.<clinit>(StaticLoggerBinder.java:55)
at org.slf4j.LoggerFactory.bind(LoggerFactory.java:121)
at org.slf4j.LoggerFactory.performInitialization(LoggerFactory.java:111)
at org.slf4j.LoggerFactory.getILoggerFactory(LoggerFactory.java:268)
at org.slf4j.LoggerFactory.getLogger(LoggerFactory.java:241)
at org.apache.commons.logging.impl.SLF4JLogFactory.getInstance(SLF4JLogFactory.java:155)
at org.apache.commons.logging.impl.SLF4JLogFactory.getInstance(SLF4JLogFactory.java:132)
at org.apache.commons.logging.LogFactory.getLog(LogFactory.java:273)
at org.springframework.boot.SpringApplication.<clinit>(SpringApplication.java:191)
at com.xmd.spa.ApplicationMain.main(ApplicationMain.java:25)
Caused by: java.lang.ClassNotFoundException: org.slf4j.event.LoggingEvent
at java.net.URLClassLoader$1.run(URLClassLoader.java:366)
at java.net.URLClassLoader$1.run(URLClassLoader.java:355)
at java.security.AccessController.doPrivileged(Native Method)
at java.net.URLClassLoader.findClass(URLClassLoader.java:354)
at java.lang.ClassLoader.loadClass(ClassLoader.java:425)
at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:308)
at java.lang.ClassLoader.loadClass(ClassLoader.java:358)
... 35 more
2016-04-26 09:37:50.019 ERROR 5000 --- [ restartedMain] o.s.boot.SpringApplication : Application startup failed
java.lang.NoClassDefFoundError: org/slf4j/event/LoggingEvent
at java.lang.Class.getDeclaredMethods0(Native Method)
at java.lang.Class.privateGetDeclaredMethods(Class.java:2615)
at java.lang.Class.privateGetPublicMethods(Class.java:2733)
at java.lang.Class.getMethods(Class.java:1472)
at java.beans.Introspector.getPublicDeclaredMethods(Introspector.java:1280)
at java.beans.Introspector.getTargetMethodInfo(Introspector.java:1141)
at java.beans.Introspector.getBeanInfo(Introspector.java:416)
at java.beans.Introspector.getBeanInfo(Introspector.java:163)
at ch.qos.logback.core.joran.util.PropertySetter.introspect(PropertySetter.java:79)
at ch.qos.logback.core.joran.util.PropertySetter.getMethod(PropertySetter.java:393)
at ch.qos.logback.core.joran.util.PropertySetter.findAdderMethod(PropertySetter.java:203)
at ch.qos.logback.core.joran.util.PropertySetter.computeAggregationType(PropertySetter.java:177)
at ch.qos.logback.core.joran.action.NestedComplexPropertyIA.isApplicable(NestedComplexPropertyIA.java:61)
at ch.qos.logback.core.joran.spi.Interpreter.lookupImplicitAction(Interpreter.java:237)
at ch.qos.logback.core.joran.spi.Interpreter.getApplicableActionList(Interpreter.java:256)
at ch.qos.logback.core.joran.spi.Interpreter.startElement(Interpreter.java:144)
at ch.qos.logback.core.joran.spi.Interpreter.startElement(Interpreter.java:129)
at ch.qos.logback.core.joran.spi.EventPlayer.play(EventPlayer.java:50)
at ch.qos.logback.core.joran.GenericConfigurator.doConfigure(GenericConfigurator.java:149)
at ch.qos.logback.core.joran.GenericConfigurator.doConfigure(GenericConfigurator.java:135)
at ch.qos.logback.core.joran.GenericConfigurator.doConfigure(GenericConfigurator.java:99)
at ch.qos.logback.core.joran.GenericConfigurator.doConfigure(GenericConfigurator.java:49)
at org.springframework.boot.logging.logback.LogbackLoggingSystem.configureByResourceUrl(LogbackLoggingSystem.java:163)
at org.springframework.boot.logging.logback.LogbackLoggingSystem.loadConfiguration(LogbackLoggingSystem.java:135)
at org.springframework.boot.logging.logback.LogbackLoggingSystem.reinitialize(LogbackLoggingSystem.java:195)
at org.springframework.boot.logging.AbstractLoggingSystem.initializeWithConventions(AbstractLoggingSystem.java:64)
at org.springframework.boot.logging.AbstractLoggingSystem.initialize(AbstractLoggingSystem.java:49)
at org.springframework.boot.logging.logback.LogbackLoggingSystem.initialize(LogbackLoggingSystem.java:106)
at org.springframework.boot.logging.LoggingApplicationListener.initializeSystem(LoggingApplicationListener.java:301)
at org.springframework.boot.logging.LoggingApplicationListener.initialize(LoggingApplicationListener.java:253)
at org.springframework.boot.logging.LoggingApplicationListener.onApplicationEnvironmentPreparedEvent(LoggingApplicationListener.java:225)
at org.springframework.boot.logging.LoggingApplicationListener.onApplicationEvent(LoggingApplicationListener.java:201)
at org.springframework.context.event.SimpleApplicationEventMulticaster.invokeListener(SimpleApplicationEventMulticaster.java:163)
at org.springframework.context.event.SimpleApplicationEventMulticaster.multicastEvent(SimpleApplicationEventMulticaster.java:136)
at org.springframework.context.event.SimpleApplicationEventMulticaster.multicastEvent(SimpleApplicationEventMulticaster.java:119)
at org.springframework.boot.context.event.EventPublishingRunListener.publishEvent(EventPublishingRunListener.java:111)
at org.springframework.boot.context.event.EventPublishingRunListener.environmentPrepared(EventPublishingRunListener.java:65)
at org.springframework.boot.SpringApplicationRunListeners.environmentPrepared(SpringApplicationRunListeners.java:54)
at org.springframework.boot.SpringApplication.createAndRefreshContext(SpringApplication.java:330)
at org.springframework.boot.SpringApplication.run(SpringApplication.java:307)
at org.springframework.boot.SpringApplication.run(SpringApplication.java:1191)
at org.springframework.boot.SpringApplication.run(SpringApplication.java:1180)
at com.xmd.spa.ApplicationMain.main(ApplicationMain.java:25)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:606)
at org.springframework.boot.devtools.restart.RestartLauncher.run(RestartLauncher.java:49)
Caused by: java.lang.ClassNotFoundException: org.slf4j.event.LoggingEvent
at java.net.URLClassLoader$1.run(URLClassLoader.java:366)
at java.net.URLClassLoader$1.run(URLClassLoader.java:355)
at java.security.AccessController.doPrivileged(Native Method)
at java.net.URLClassLoader.findClass(URLClassLoader.java:354)
at java.lang.ClassLoader.loadClass(ClassLoader.java:425)
at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:308)
at java.lang.ClassLoader.loadClass(ClassLoader.java:358)
... 48 common frames omitted
2016-04-26 09:37:50.024 INFO 5000 --- [ restartedMain] .b.l.ClasspathLoggingApplicationListener : Application failed to start with classpath: [file:/E:/maven_workspace/spa/spa-web-mgr/target/classes/]
弄了好久，网上也没有查到什么问题。但是另一个springboot项目是正常，于是找了两个不同的地方，发现是logback.xml的问题，修改之前如下(这里只显示重要部分)：
<root>
<logger name="info" level="INFO"/>
<logger name="error" level="ERROR"/>
<logger name="console" level="INFO"/>
</root>
修改之后如下:
<root>
<appender-ref ref="console" level="INFO"/>
<appender-ref ref="info" level="INFO"/>
<appender-ref ref="error" level="ERROR"/>
</root>
哪个天杀的自己写成这样(貌似在骂自己，哈哈)。修改之后启动springboot成功！