title: IntelliJ IDEA Ultimate 2018.3 thinks my Java 9 Project is a Kotlin Project
body: <p>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 looks like this:
  <a href="https://i.stack.imgur.com/yu80J.png" rel="noreferrer"><img src="https://i.stack.imgur.com/yu80J.png" alt="Run Configuration"></a></p>
  
  <p>My project settings look like this:
  <a href="https://i.stack.imgur.com/kb0cS.png" rel="noreferrer"><img src="https://i.stack.imgur.com/kb0cS.png" alt="Project Settings"></a></p>
  
  <p>I can build everything with Maven just fine. However, when I try to compile with IntelliJ, it somehow thinks that my project is a Kotlin project and can't compile it:</p>
  
  <p><a href="https://i.stack.imgur.com/JuFid.png" rel="noreferrer"><img src="https://i.stack.imgur.com/JuFid.png" alt="Error message"></a></p>
  
  <blockquote>
    <p>Error:Kotlin: The Kotlin standard library is not found in the module graph. Please ensure you have the 'requires kotlin.stdlib' clause in your module definition</p>
  </blockquote>
  
  <p>Has anyone any idea how to fix this? I already tried deleting the run configuration and recreated it. This fixes the problem for some time, but then it reappears randomly.</p>