Log4j Concepts

Internal

• log4j

Logger

Logger is the central class in the log4j package. Most logging operations, except configuration, are done through this class.

Category deprecation note: Logger is a subclass of Category and extends it. Category has been deprecated. Internally, whenever log4j is asked to produce a Category object, it will instead produce a Logger object. In order to preserve backward compatibility, methods that previously accepted category objects still continue to accept category objects.

Category

This class has been deprecated and replaced with the Logger subclass. There is no need for new client code to use or refer to the Category class.