failed to load class 'org.slf4j.impl.StaticLoggerBinder'

Question

I created a jar file with all the dependencies, and I implemented the logging using slf4j + logback. Thus I have a logback.xml file defined for all the loggers. However when I run the jar it gave me this message:

SLF4J: Failed to load class "org.slf4j.impl.StaticLoggerBinder".
SLF4J: Defaulting to no-operation (NOP) logger implementation
SLF4J: See http://www.slf4j.org/codes.html#StaticLoggerBinder for further details.

I dont see any logging happening. After I unzip the jar file, I can see the org.slf4j folder. I don't know why this is not working.

Answer 1

From http://www.slf4j.org/codes.html#StaticLoggerBinder (the link in the message):

This error is reported when the org.slf4j.impl.StaticLoggerBinder class could not be loaded into memory. This happens when no appropriate SLF4J binding could be found on the class path. Placing one (and only one) of slf4j-nop.jar, slf4j-simple.jar, slf4j-log4j12.jar, slf4j-jdk14.jar or logback-classic.jar on the class path should solve the problem. SINCE 1.6.0 As of SLF4J version 1.6, in the absence of a binding, SLF4J will default to a no-operation (NOP) logger implementation. You can download SLF4J bindings from the project download page.

In other words, you need a slf4j backend in your classpath, e.g. logback.