具体问题描述如下:
SLF4J: Class path contains multiple SLF4J bindings.
SLF4J: Found binding in [jar:file:/D:/maven/repository/org/apache/logging/log4j/log4j-slf4j-impl/2.6.2/log4j-slf4j-impl-2.6.2.jar!/org/slf4j/impl/StaticLoggerBinder.class]
SLF4J: Found binding in [jar:file:/D:/maven/repository/ch/qos/logback/logback-classic/1.2.0/logback-classic-1.2.0.jar!/org/slf4j/impl/StaticLoggerBinder.class]
SLF4J: See http://www.slf4j.org/codes.html#multiple_bindings for an explanation.
SLF4J: Actual binding is of type [org.apache.logging.slf4j.Log4jLoggerFactory]
java.lang.NoClassDefFoundError: org/apache/logging/log4j/util/ReflectionUtil
at org.apache.logging.slf4j.Log4jLoggerFactory.getContext(Log4jLoggerFactory.java:42)
at org.apache.logging.log4j.spi.AbstractLoggerAdapter.getLogger(AbstractLoggerAdapter.java:48)
at org.apache.logging.slf4j.Log4jLoggerFactory.getLogger(Log4jLoggerFactory.java:29)
at org.slf4j.LoggerFactory.getLogger(LoggerFactory.java:358)
at org.apache.commons.logging.impl.SLF4JLogFactory.getInstance(SLF4JLogFactory.java:156)
at org.apache.commons.logging.impl.SLF4JLogFactory.getInstance(SLF4JLogFactory.java:132)
at org.apache.commons.logging.LogFactory.getLog(LogFactory.java:655)
at org.springframework.test.context.junit4.SpringJUnit4ClassRunner.<clinit>(SpringJUnit4ClassRunner.java:99)
at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:62)
at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45)
at java.lang.reflect.Constructor.newInstance(Constructor.java:423)
at org.junit.internal.builders.AnnotatedBuilder.buildRunner(AnnotatedBuilder.java:104)
at org.junit.vintage.engine.discovery.DefensiveAllDefaultPossibilitiesBuilder$DefensiveAnnotatedBuilder.buildRunner(DefensiveAllDefaultPossibilitiesBuilder.java:114)
at org.junit.internal.builders.AnnotatedBuilder.runnerForClass(AnnotatedBuilder.java:86)
at org.junit.runners.model.RunnerBuilder.safeRunnerForClass(RunnerBuilder.java:59)
at org.junit.internal.builders.AllDefaultPossibilitiesBuilder.runnerForClass(AllDefaultPossibilitiesBuilder.java:26)
at org.junit.vintage.engine.discovery.DefensiveAllDefaultPossibilitiesBuilder.runnerForClass(DefensiveAllDefaultPossibilitiesBuilder.java:57)
at org.junit.runners.model.RunnerBuilder.safeRunnerForClass(RunnerBuilder.java:59)
at org.junit.vintage.engine.discovery.ClassSelectorResolver.resolveTestClass(ClassSelectorResolver.java:66)
at org.junit.vintage.engine.discovery.ClassSelectorResolver.resolve(ClassSelectorResolver.java:47)
at org.junit.platform.engine.support.discovery.EngineDiscoveryRequestResolution.lambda$resolve$2(EngineDiscoveryRequestResolution.java:134)
at java.util.stream.ReferencePipeline$3$1.accept(ReferencePipeline.java:193)
at java.util.ArrayList$ArrayListSpliterator.tryAdvance(ArrayList.java:1361)
at java.util.stream.ReferencePipeline.forEachWithCancel(ReferencePipeline.java:126)
at java.util.stream.AbstractPipeline.copyIntoWithCancel(AbstractPipeline.java:499)
at java.util.stream.AbstractPipeline.copyInto(AbstractPipeline.java:486)
at java.util.stream.AbstractPipeline.wrapAndCopyInto(AbstractPipeline.java:472)
at java.util.stream.FindOps$FindOp.evaluateSequential(FindOps.java:152)
at java.util.stream.AbstractPipeline.evaluate(AbstractPipeline.java:234)
at java.util.stream.ReferencePipeline.findFirst(ReferencePipeline.java:464)
at org.junit.platform.engine.support.discovery.EngineDiscoveryRequestResolution.resolve(EngineDiscoveryRequestResolution.java:185)
at org.junit.platform.engine.support.discovery.EngineDiscoveryRequestResolution.resolve(EngineDiscoveryRequestResolution.java:125)
at org.junit.platform.engine.support.discovery.EngineDiscoveryRequestResolution.resolveCompletely(EngineDiscoveryRequestResolution.java:91)
at org.junit.platform.engine.support.discovery.EngineDiscoveryRequestResolution.run(EngineDiscoveryRequestResolution.java:82)
at org.junit.platform.engine.support.discovery.EngineDiscoveryRequestResolver.resolve(EngineDiscoveryRequestResolver.java:113)
at org.junit.vintage.engine.discovery.VintageDiscoverer.discover(VintageDiscoverer.java:44)
at org.junit.vintage.engine.VintageTestEngine.discover(VintageTestEngine.java:63)
at org.junit.platform.launcher.core.DefaultLauncher.discoverEngineRoot(DefaultLauncher.java:181)
at org.junit.platform.launcher.core.DefaultLauncher.discoverRoot(DefaultLauncher.java:168)
at org.junit.platform.launcher.core.DefaultLauncher.execute(DefaultLauncher.java:132)
at com.intellij.junit5.JUnit5IdeaTestRunner.startRunnerWithArgs(JUnit5IdeaTestRunner.java:71)
at com.intellij.rt.junit.IdeaTestRunner$Repeater$1.execute(IdeaTestRunner.java:38)
at com.intellij.rt.execution.junit.TestsRepeater.repeat(TestsRepeater.java:11)
at com.intellij.rt.junit.IdeaTestRunner$Repeater.startRunnerWithArgs(IdeaTestRunner.java:35)
at com.intellij.rt.junit.JUnitStarter.prepareStreamsAndStart(JUnitStarter.java:235)
at com.intellij.rt.junit.JUnitStarter.main(JUnitStarter.java:54)
Caused by: java.lang.ClassNotFoundException: org.apache.logging.log4j.util.ReflectionUtil
at java.net.URLClassLoader.findClass(URLClassLoader.java:387)
at java.lang.ClassLoader.loadClass(ClassLoader.java:418)
at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:355)
at java.lang.ClassLoader.loadClass(ClassLoader.java:351)
... 47 more
原因分析:
上述是由于找不到org/apache/logging/log4j/util/ReflectionUtil类造成,
定位到Log4jLoggerFactory.java:42,发现确实是加载不到这个类造成的。如下图所示:
接下来就要解决,为什么加载不到这个类的问题。
然后发现,这个类所在的包是新引入的,而这个包是在新加入依赖后,间接被引入的,因此在新引入的包中,将其排除即可。
其他可能原因:版本问题导致,如java - I'm getting "NoClassDefFoundError: org/apache/logging/log4j/util/ReflectionUtil" - Stack Overflow