NullPointerException与带有Maven的log4j

Question

I have main pom, and two modules (sub poms), first of them contains dependency to log4j. First module - some utility classes. Second - tests for first module (jcstress) that compiles to sub-jar using shade plugin. compilation works fine, but then run tests (second module), it fails with this error. I have to dependencies for log4j in first module and they are copied to second one:

   <dependency>
        <groupId>org.apache.logging.log4j</groupId>
        <artifactId>log4j-api</artifactId>
        <version>2.11.0</version>
    </dependency>

    <dependency>
        <groupId>org.apache.logging.log4j</groupId>
        <artifactId>log4j-core</artifactId>
        <version>2.11.0</version>
    </dependency> 

Exception in thread "main" java.lang.ExceptionInInitializerError at avalsa.util.ConcurrentSortedLinkedList.(ConcurrentSortedLinkedList.java:12) at java.lang.Class.forName0(Native Method) at java.lang.Class.forName(Class.java:264) at org.openjdk.jcstress.util.Reflections.getClasses(Reflections.java:64) at org.openjdk.jcstress.vm.ContendedTestMain.main(ContendedTestMain.java:44) Caused by: java.lang.NullPointerException at org.apache.logging.log4j.util.LoaderUtil.getClassLoaders(LoaderUtil.java:115) at org.apache.logging.log4j.util.ProviderUtil.(ProviderUtil.java:66) at org.apache.logging.log4j.util.ProviderUtil.lazyInit(ProviderUtil.java:146) at org.apache.logging.log4j.util.ProviderUtil.hasProviders(ProviderUtil.java:130) at org.apache.logging.log4j.LogManager.(LogManager.java:89) ... 5 more

Any ideas?

Answer 1

Remove log4j dependency in your POM and Add this dependency

        <dependency>
            <groupId>log4j</groupId>
            <artifactId>log4j</artifactId>
            <version>1.2.12</version>
        </dependency>