title: intellij plugin SDK can't resolve java
body: <p>my plugin project can't find any java classes. 
  How can I make my project compile again?
  I'm developing on manjaro</p>
  
  <p>project: <a href="https://github.com/axaluss/power-mode-intellij-plugin" rel="nofollow noreferrer">https://github.com/axaluss/power-mode-intellij-plugin</a></p>
  
  <pre><code>DISTRIB_ID=ManjaroLinux
  DISTRIB_RELEASE=18.1.2
  DISTRIB_CODENAME=Juhraya
  DISTRIB_DESCRIPTION="Manjaro Linux"
  </code></pre>
  
  <pre><code>IntelliJ IDEA 2019.2.4 (Community Edition)
  Build #IC-192.7142.36, built on October 29, 2019
  Runtime version: 11.0.4+10-b304.77 amd64
  VM: OpenJDK 64-Bit Server VM by JetBrains s.r.o
  Linux 5.2.21-1-MANJARO
  GC: ParNew, ConcurrentMarkSweep
  Memory: 1948M
  Cores: 6
  Registry: 
  Non-Bundled Plugins: Batch Scripts Support, CMD Support, dcevm, de.ax.powermode, mobi.hsz.idea.gitignore, net.seesharpsoft.intellij.plugins.csv, org.intellij.scala, BashSupport, org.toml.lang, some.awesome
  </code></pre>
  
  <p><a href="https://i.stack.imgur.com/QLHf4.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/QLHf4.png" alt="can&#39;t find java.io.File"></a></p>