Your ultimate Java software directory. Using log4j you can log to a file, a java.io.Writer, a remote server, or a syslog daemon. The package is designed so that log statements can remain in shipped code without incurring a high performance cost. One distinctive feature of log4j is the notion of hierarchical categories. The PatternLayout lets the user customize the output format without writing any code.
Users can choose to implement their own log formats and output strategies.
Log4j is an incredibly well designed and functional logging tool. Previously I was using another Java logging library developed internally within my company which I liked. I had no desire to learn another but did so for the sake of due diligence. Log4j has the following features which set it apart from others I have seen. This allows you to change the characteristics of your logging without changing code.