Imo, the main point of a system like log4j or slf4j if the ability to have logging in your service up to the point of it being a massive performance impact - an

Imo, the main point of a system like log4j or slf4j if the ability to have logging in your service up to the point of it being a massive performance impact - and keep it disabled. For example, Hibernate has full query logging built in, but even if you filter locally with some logging demon, pushing 100 - 1k queries / second to stdout or a file is going to cripple performance. With a logging framework like Log4J or SLF4J you can have this query logging, and you can enable it within 1 monitor run (usually 60s) at runtine and disable it 4-5 minutes later. This is very, very powerful in production.