// Once you have included the Log4j jar into the classpath of your
// application, you can use the following code within each class to
// get a logger for that class. That is, all log messages issued from
// within that class will be tagged with the classname to make it
// easier to locate a problem. See my tutorial on Log4j,
// Log4j in 30 Minutes or Less (http://www.johnmunsch.com/projects/Presentations/)
// for a better introduction.

private static Logger log = Logger.getLogger(<class name>.class);

// When you need to specify the location (or a different name) for
// the log.properties file, you can set a specific System variable
// which Log4j will be guaranteed to read as soon as any part of
// your code tries to use it. You do that by passing the following
// to the JVM as you start your Java application.

-Dlog4j.configuration=file:<path to log.properties file>