[TOMEE-4390] ClassNotFoundException in webapp that has log4j2 and invokes commons-logging

• Type: Bug
• Status: Resolved
• Priority: Major
• Resolution: Fixed
• Affects Version/s: 10.0.0-M2
• Fix Version/s: 10.0.0-M3
• Component/s: TomEE Core Server
• Assignee: Unassigned
• Reporter: Markus Jung
• Created: 03/Sep/24 08:41
• Updated: 05/Sep/24 12:59
• Resolved: 05/Sep/24 12:57

Description

Accessing commons-logging throws an exception when it is being invoked in an application that has a log4j2 dependency but no commons-logging dependency. Might possibly also be a commons-logging bug? Really not sure

The layout is basically:

• tomee
  • libs/
    • commons-logging.jar
  • webapps/ROOT/WEB-INF/libs
    • log4j2-api/core.jar

 

This causes the following to happen:

1. commons-logging checks the current thread classloader for a log4j2 class
2. if it finds one, it creates an instance of Log4jApiLogFactory
3. while doing so, java tries to load the class org.apache.logging.log4j.spi.LoggerAdapter using the classloader that loaded commons-logging.jar
4. ClassNotFoundException with a very incomprehensible stacktrace

 

See attached reproducer, simply run mvn package tomee:run

 

Stacktrace:

        Caused by: java.lang.NoClassDefFoundError: org/apache/logging/log4j/spi/LoggerAdapter
                at java.base/java.lang.Class.forName0(Native Method)
                at java.base/java.lang.Class.forName(Class.java:375)
                at org.apache.commons.logging.LogFactory.createFactory(LogFactory.java:419)
                at org.apache.commons.logging.LogFactory.lambda$newFactory$3(LogFactory.java:1431)
                at java.base/java.security.AccessController.doPrivileged(AccessController.java:318)
                at org.apache.commons.logging.LogFactory.newFactory(LogFactory.java:1431)
                at org.apache.commons.logging.LogFactory.getFactory(LogFactory.java:928)
                at org.apache.commons.logging.LogFactory.getLog(LogFactory.java:987)
                at com.example.ExampleBean.initApplication(ExampleBean.java:15)
                at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
                at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:77)
                at java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
                at java.base/java.lang.reflect.Method.invoke(Method.java:569)
                at org.apache.webbeans.event.ObserverMethodImpl.invoke(ObserverMethodImpl.java:410)
                at org.apache.webbeans.event.ObserverMethodImpl.notify(ObserverMethodImpl.java:371)
                ... 49 more
        Caused by: java.lang.ClassNotFoundException: org.apache.logging.log4j.spi.LoggerAdapter
                at java.base/java.net.URLClassLoader.findClass(URLClassLoader.java:445)
                at java.base/java.lang.ClassLoader.loadClass(ClassLoader.java:592)
                at java.base/java.lang.ClassLoader.loadClass(ClassLoader.java:525)
                ... 64 more

 

Issue Links

• relates to: TOMEE-4394 Commons Logging 1.3.4