Maven build [WARNING] we have a duplicate class

Question

Anybody has any idea what happened to my maven build? I am getting a lot of duplicate warnings.

[WARNING] We have a duplicate org/apache/commons/logging/impl         


        

Answer 1

In my case, my parent pom was including commons-beanutils and my child module (which is the only thing I wanted to compile) was including commons-io.

The shade plug in complained about duplicates since commons-io and commons-beansutil shared some common classes. Note that beansutiul was being included even though it was not needed, and was not used.

I solve this by minimizing the jar by adding this to the configuration:

true

Now the shade plugin did not add unused resources.

Warning went away.