ALL > TRACE > DEBUG > INFO > WARN > ERROR > FATAL > OFF or how works Log4j levels in our shitty application

Posted by on October 15, 2013

Dealing with Log4j will push us inevitably (but in a good way) to work with Appenders and Levels.

When that moment arrives, and we configure our log4j.properties to just INFO messages.

We will discover there are other type of messages. And thats because of Levels! There is a hierarchy!

Works in this way:

  • TRACE: Shows messages classified as DEBUG, INFO, WARNING,ERROR and FATAL
  • DEBUG: Shows messages classified as DEBUG, INFO, WARNING, ERROR, and FATAL
  • INFO: Shows messages classified as INFO, WARNING, ERROR, and FATAL
  • WARNING: Shows messages classified as WARNING, ERROR, and FATAL
  • ERROR: Shows messages classified as ERROR and FATAL
  • FATAL: shows messages at a FATAL level only
  • ALL: You are a genius! Turn on all logging.
  • OFF: Yes you are! Turn off all logging.

Let’s put this into a drawing:

And that’s all folks.


Related Posts