Using log4j2 from endorsed dirs

Question

My example code is as simple as that:

import org.apache.log4j.Logger;
public class Test {
    public static void main(String args[]){
        LOG.info("information log line");
    }
    private final static Logger LOG = Logger.getLogger(Test.class);
}

It compiles and runs fine with log4j 2.11.0.

For a project that uses jacORB, I need to put the log4j jar files log4j-core-2.11.0.jar and log4j-api-2.11.0.jar into a directory that is added to the application via -Djava.endorsed.dirs=someDir . So, when I copy the log4j-jars into a subdirectory edDir and run the above example with

java -Djava.endorsed.dirs=edDir -Dlog4j.configurationFile=log4j.xml Test

It terminates with this output:

Exception in thread "main" java.lang.ExceptionInInitializerError
    at org.apache.log4j.Logger.getLogger(Logger.java:41)
    at Test.<clinit>(Test.java:7)
Caused by: java.lang.NullPointerException
    at org.apache.logging.log4j.util.LoaderUtil.getClassLoaders(LoaderUtil.java:115)
    at org.apache.logging.log4j.util.ProviderUtil.<init>(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.<clinit>(LogManager.java:89)
    ... 2 more

It used to work with log4j 2.6. The error described above occured after upgrading to log4j 2.11.0.

Am I doing something wrong? How can I make this work again?

BTW, the JRE is 1.7.

Answer 1

Did you try with the command line parameter log4j.ignoreTCL=true

This parameter seems to be designed to look for the class on all classloaders.

So something like java -Djava.endorsed.dirs=edDir -Dlog4j.configurationFile=log4j.xml -Dlog4j.ignoreTCL=true Test

Answer 2

Just built your project in eclipse using the example above (log4j-core-2.11.0.jar and log4j-api-2.11.0.jar) - you need to change your import statements and change Logger to LogManager:

import org.apache.logging.log4j.LogManager;
import org.apache.logging.log4j.Logger;



public class Test {

    public static void main(String[] args) {
        // TODO Auto-generated method stub
        LOG.info("information log line");
    }
    // private static final ExtLogger logger = ExtLogger.create(MyService.class);
    private final static Logger LOG = LogManager.getLogger(Test.class);
}

Answer 3

The problem occured when log4j classes were loaded by the Bootstrap classloader, which is the case when the log4j jar files are found in the endorsed directory ( -Djava.endorsed.dirs=... ). Log4j didn't handle that correctly (see stacktrace in opening post).

The issue has been resolved in log4j 2.11.1.