There’s nothing wrong with IDEA, nor your dependencies or local maven caches, it’s correctly identifying the mismatch.
Here’s how to check:
- Open class in question
- Click “Show diff”
- Choose “Ignore whitespaces and empty lines”
You can clearly see (ignoring JavaDoc and FQCNs) that the class file has extra checks included for the @NonNull annotated arguments. The import says lombok.NonNull, and the documentation shows this transformation will happen.
I guess the best course of action is either to ignore this warning or ask the project’s maintainers to build the sources.jar from the lombok-processed source code if that’s possible. I think they’ll need to employ delomboking and this Maven plugin, but never built lombok code myself.