When I tried to Run a .java file during the build I got the following Error
Module 'JAVA-Workspace' production: java.lang.ClassCastException: class org.jetbrains.jps.builders.java.dependencyView.TypeRepr$PrimitiveType cannot be cast to class org.jetbrains.jps.builders.java.dependencyView.TypeRepr$ClassType (org.jetbrains.jps.builders.java.dependencyView.TypeRepr$PrimitiveType and org.jetbrains.jps.builders.java.dependencyView.TypeRepr$ClassType are in unnamed module of loader java.net.URLClassLoader @490d6c15)
'JAVA-Workspace' is my project directory.
It was fine a few minutes ago I was debugging the same file.
I did not install any new plugins at the time.
Java 11 | 
I tried :
- Remove caches and indexes by
Invalidate and Restart<Invalidate Caches<File. - Delete
.ideain root directory of the project.
Thank You