Static private methods should be generated in case of aaa.bbb to ccc mapping

Example:

public interface AddonMapper extends Function<Addon, AddonProxy> {
    @Override
    @Mapping(source = "addonCategory.value", target = "addonCategory")
    @Mapping(source = "addonCategory.translation", target = "addonCategoryTranslated")
    AddonProxy apply(Addon addon);
}

// Generates private method like that, but this method should be STATIC:

private String addonAddonCategoryValue(Addon addon) {
        if ( addon == null ) {
            return null;
        }
        TranslatedValue addonCategory = addon.getAddonCategory();
        if ( addonCategory == null ) {
            return null;
        }
        String value = addonCategory.getValue();
        if ( value == null ) {
            return null;
        }
        return value;
    }

Start from the example in the issue and trace how MapStruct generates private helper methods for nested mappings such as addonCategory.value. Determine where that generated method is selected for instance versus static generation. Done means the helper for this mapping is static while preserving the shown null-safe behavior, with corresponding generated-code coverage added where the project’s tests support it.