How to find which library slf4j has bound itself t

问题:

I am using slf4j for logging in my application. I get the purpose of slf4j. I would like to know how to find out which logging-library slf4j is currently binding to. I have log4j in my referenced libraries. I am assuming that slf4j has bound itself to log4j.

What I would like to know is, is there any way to explicitly confirm this binding?

回答1:

Just do what SLF4J does to discover the binding:

final StaticLoggerBinder binder = StaticLoggerBinder.getSingleton();

Now you can try to find out what is the actual implementation logback in my case:

System.out.println(binder.getLoggerFactory());
System.out.println(binder.getLoggerFactoryClassStr());

This prints:

ch.qos.logback.classic.LoggerContext[default]
ch.qos.logback.classic.selector.DefaultContextSelector

回答2:

The StaticLoggerBinder's getLoggerFactoryClassStr() method is probably what you're looking for.

回答3:

Easy. Put a breakpoint on .. say.. LOG.info(...). Once debugger stops there, step into.. and viola.. you will find yourself in the code of the actual logger... say log4j or logback.. whatever.