IntelliJ won't accept FileTypeFactory

Question

I am attempting to follow the Language and File Type tutorial for JetBrains IntelliJ

It worked, once. Now (whatever I do) I receive an assertion failure stating that it was expecting an instance of FileTypeFactory and got my SimpleFileTypeFactory

My public class SimpleFileTypeFactory extends com.intellij.openapi.fileTypes.FileTypeFactory so I'm not sure how to react to this ...

Caused by: java.lang.AssertionError: Expected: class com.intellij.openapi.fileTypes.FileTypeFactory; Actual: class bengie.idea.SimpleFileTypeFactory
  at com.intellij.openapi.extensions.impl.ExtensionPointImpl.assertClass(ExtensionPointImpl.java:408)
  at com.intellij.openapi.extensions.impl.ExtensionPointImpl.processAdapters(ExtensionPointImpl.java:242)
  at com.intellij.openapi.extensions.impl.ExtensionPointImpl.getExtensions(ExtensionPointImpl.java:185)

... especially when Google has no matches for "Expected: class com.intellij.openapi.fileTypes.FileTypeFactory; Actual"

Has anyone resolved this sort of thing?

Answer 1

I was depending on a Maven module (actually, two of them) The rest of my project is built with Maven so it seemed logical and looked like it would work. I didn't remember the build seizing up when I added them, so I had forgotten about it. Removing the dependency, starting a debug session, uninstalling the plugin, rinse, repeat and I eventually stopped seeing error messages.

I've since stuffed the maven modules into a jar-with-dependencies and told the IntelliJ plugin module to load the resulting .jar No problems so far - Yay!