SLF4J(W): No SLF4J providers were found

[sjlillian]

Hey!

I am working on a project that is using the smile.api library, but whenever I try to run the application I get this warning that stops the application:

SLF4J(W): No SLF4J providers were found.
SLF4J(W): Defaulting to no-operation (NOP) logger implementation
SLF4J(W): See https://www.slf4j.org/codes.html#noProviders for further details.
Exception in thread "main" java.lang.UnsupportedOperationException
        at smile.data.vector.ValueVector.intStream(ValueVector.java:238)
        at smile.data.vector.ValueVector.toIntArray(ValueVector.java:266)
        at smile.classification.ClassLabels.fit(ClassLabels.java:136)
        at smile.classification.RandomForest.fit(RandomForest.java:321)
        at smile.classification.RandomForest.fit(RandomForest.java:295)
        at com.sjl.mtgai.logicLayer.Predictor.<init>(Predictor.java:14)
        at com.sjl.mtgai.LogicLayerController.logic(LogicLayerController.java:12)
        at com.sjl.mtgai.App.main(App.java:13)

I have messed around with my pom.xml file and searched around the internet but have found no answers.

My project can be found here.

Some information about my project:

I am trying to create an application that would be able to guess if a deck the user provides could win a Magic: The Gather commander tournament. I have collected tournament, deck, and card data and am trying to use it all to build a random forest algorithm. As of the current branch in the project, I am only testing a small amount of my data and have gotten all of the data translated into POJO's. I can see that the application gets right up until it starts using the smile libraries, creating the warning above.

Any help to fix this issue would be greatly appreciated!

[kklioss]

Smile leverages SLF4J for logging so that the user can use a variety of logging libraries per their own preference. The above warning is not fatal. Basically, it says that no log messages will be printed as no logging provider is available. If you would like to see Smile's log message, you can add slf4j-simple to your project. It will simply print out the log messages on the console. For more advanced use cases and controls, you may use logback or log4j. See this tutorial for more information.

[sjlillian]

I have tried adding sl4j-simple into my pom file but that hasn't worked. But I did try using logback and that worked!