Class loader issue with Log4j in infinispan-embedded

I would like to bring to your attention an issue with Log4j shadowing in infinispan-embedded.

After a recent upgrade to Log4j 2.6 in our app where we have an infinispan-embedded dependency, we started getting occasional class loader exceptions. A quick inspection with JHades showed that the infinispan-embedded JAR includes a copy of Log4j, introduced by the shadow Maven plugin, but without rewriting the Log4j package names.

Is there any specific reason to shadow Log4j like this?

It also puzzles why we get this exception at all, since Log4j 2.x APIs should not change at all.

{{5-Jul-2016 11:53:45.434 SEVERE [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[/c2id]]
at
org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:154)
at
org.apache.catalina.core.ContainerBase.addChildInternal(ContainerBase.java:725)
at
org.apache.catalina.core.ContainerBase.addChild(ContainerBase.java:701)
at
org.apache.catalina.core.StandardHost.addChild(StandardHost.java:717)
at
org.apache.catalina.startup.HostConfig.deployWAR(HostConfig.java:945)
at
org.apache.catalina.startup.HostConfig$DeployWar.run(HostConfig.java:1795)
at java.util.concurrent.Executors$RunnableAdapter.call(Unknown
Source)
at java.util.concurrent.FutureTask.run(Unknown Source)
at java.util.concurrent.ThreadPoolExecutor.runWorker(Unknown Source)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(Unknown
Source)
at java.lang.Thread.run(Unknown Source)
Caused by: java.lang.NoSuchMethodError:
org.apache.logging.log4j.status.StatusLogger.debug(Ljava/lang/String;Ljava/lang/Object;)V
at
org.apache.logging.log4j.core.impl.Log4jContextFactory.<init>(Log4jContextFactory.java:91)
at
org.apache.logging.log4j.core.impl.Log4jContextFactory.<init>(Log4jContextFactory.java:58)
at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native
Method)
at sun.reflect.NativeConstructorAccessorImpl.newInstance(Unknown
Source)
at
sun.reflect.DelegatingConstructorAccessorImpl.newInstance(Unknown Source)
at java.lang.reflect.Constructor.newInstance(Unknown Source)
at java.lang.Class.newInstance(Unknown Source)
at org.apache.logging.log4j.LogManager.<clinit>(LogManager.java:93)
at
org.apache.logging.log4j.core.config.Configurator.getFactory(Configurator.java:45)
at
org.apache.logging.log4j.core.config.Configurator.initialize(Configurator.java:157)
at
org.apache.logging.log4j.web.Log4jWebInitializerImpl.initializeNonJndi(Log4jWebInitializerImpl.java:168)
at
org.apache.logging.log4j.web.Log4jWebInitializerImpl.start(Log4jWebInitializerImpl.java:110)
at
org.apache.logging.log4j.web.Log4jServletContainerInitializer.onStartup(Log4jServletContainerInitializer.java:57)
at
org.apache.catalina.core.StandardContext.startInternal(StandardContext.java:5244)
at
org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:150)
... 10 more}}