Intellij: Build | Build Artifacts deactivated

It's likely that you haven't configured that you want to build a .JAR/Artifact.

If you go to to your Project Settings by doing:

Ctrl+Shift+Alt+S

and click on the Artifacts tab on the side.

Then click the Green + at the top, you'll be able to configure your project to build an artifact.

Then Build > Build Artifacts... should not be greyed out and your should be able to build your JAR.

In my case i solved this problem with;

Open pom.xml,

Right Click > Run Maven -> Reimport

After this, i was be able to Build Artifacts.