Log4j explanation

This article helped me get around a problem at work. It was so simple and so helpful all at once.

Thank you sir!

Specifically what I was trying to do was to find out what logging was being done by some classes I was trying to test with JUnit Testing with an Eclipse plugin. I didn't know how the server I was interacting with was trying to find the log4j properties (what file name at what path) and I was having no luck seeing the log messages for the classes I was trying to test because there was no category set for them.

I would receive warning like this:
log4j:WARN No appenders could be found for logger(somePackageName.someClassName).
log4j:WARN Please initialize the log4j system properly.

In order to add a specific appenders to DEBUG and ERROR level messages from my class I need to find the log4j configuration.

In the Eclipse Debug Configurations on my JUnit test configuration, click on the Arguments tab. For VM Arguments I had the following:

-ea -Xmx256m -Dlog4j.debug

That did the trick, I was able to see in the console a message stating the xxx.properties was not found.
With that information I updated the properties file in the path it was looking for to add a category for the packages under test, and to change the appenders to point to new log files in my Eclipse project.