The Log4j project has become
the de facto logging standard in the java community. Even with the
introduction of built in logging in J2SE 1.4, Log4j still remains the premiere
logging framework for java. The built in library java.util.logging provides
convenience but lacks the features of the more mature Log4j. However, not including the extra appenders
and formatting that Log4j offers the function of the two libraries are very
similar. In my opinion you are much
better off using the Log4j framework from the start and sticking with it. The extra functionality has been worth it, at
least in my experience.
Another advantage of Log4j is that there are versions of
Log4X available for almost every major language.
I also use
Log4net for my C# development and
it is very nice to be able to switch languages but maintain a very familiar
framework.
Almost all the configuration and
even the method calls and classes remain virtually unchanged.
One caveat is that Log4net is in some kind of
purgatory at the Apache foundation waiting for official project status.
I notice most of their releases are labeled
as beta but I have not had any issues with it so far.
Your mileage may vary.
When you need logging, Log4X should be your first choice no
matter what language you are using.