IntelliJ IDEA Ultimate 2018.3 thinks my Java 9 Project is a Kotlin Project

Question

I have an IntelliJ project composing several subprojects which are all Java 9 modules. I use Maven as a build system. My project has no \"Facets\". My run configuration look

Answer 1

Even in 2019.1.3 that error is there .

A solution that always works for me is :

Build menu => Rebuild Project

Tested with JDK 12.0.1

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That should be fixed though by IntelliJ team as soon as possible as more and more Java projects are passing to JDK 11 ++