Maven JAR Plugin 3.0.2 Error: You have to use a classifier to attach supplemental artifacts to the project instead of replacing them

Question

Maven JAR plugin (version 3.0.2) keeps throwing the following error, even for a single invocation of the jar goal:

[ERR

Answer 1

If your logs shows something like:

[INFO] --- maven-jar-plugin:3.0.2:jar (default-jar) @ test --
[WARNING] JAR will be empty - no content was marked for inclusion!

Adding a single useless class in src/main/java seems to solve the issue see:

http://maven.40175.n5.nabble.com/quot-mvn-clean-verify-deploy-quot-causes-jar-plugin-to-execute-twice-td5877166.html