Java Development Tools

I have tried using the java.util.logging API and commons-logging to log messages. Both methods will successfully generate log output to the JDeveloper console window, (though filtering log levels does not seem to be working). But I cannot find the log output in any log files anywhere. I have looked in the embedded oc4j log files, nothing there. So I have 3 questions:

1) Which logging framework is the best one to use with JDeveloper: (java.util.logging, commons-logging, log4j, etc.)?

2) What's the proper way to configure the framework in 1)?

3) Where is the log file found that is generated?

Thanks,

Brad