How to add an annotation with valid scoping construct on return type?

[adamretter]

I am trying to create a plugin which adds JSpecify annotations like org.jspecify.annotations.NonNull and @link org.jspecify.annotations.Nullable.

These annotations are more precise than the JSR 305 annotations about where they may be placed.

The vanilla code generated by JAXB 4.0.5 in my ObjectFactory looks like:

public Catalog.TestSet createCatalogTestSet() {
    return new Catalog.TestSet();
}

Previously, with JSR 305 you could write:

@javax.annotation.Nonnull
public Catalog.TestSet createCatalogTestSet() {
  return new Catalog.TestSet();
}

I could generate that just fine in my JAXB plugin by calling: method.annotate(javax.annotation.Nonnull.class) where method is an instance of com.sun.codemodel.JMethod.

However, with JSpecify you need to write:

public Catalog.@org.jspecify.annotations.NonNull TestSet createCatalogTestSet() {
  return new Catalog.TestSet();
}

Calling method.annotate(org.jspecify.annotations.NonNull.class) from my plugin generates the incorrect code:

@org.jspecify.annotations.NonNull 
public Catalog.TestSet createCatalogTestSet() {
  return new Catalog.TestSet();
}

Instead of method.annotate(org.jspecify.annotations.NonNull.class), I tried calling the following in my plugin:

final JType returnType = method.type();
((JDefinedClass) returnType).annotate(org.jspecify.annotations.NonNull.class)

but when I do, I get no annotation at all in the generated code. I can't figure out how to call the appropriate codemodel method to get the annotation into the correct place. How can I do that please?