@CompileStatic
@Canonical
class HeaderExtractorFactory {

    AnnotationBasedHeaderExtractor forType(Class<? extends AnnotationBasedHeader> header){
        return new AnnotationBasedHeaderExtractor()
    }

    FieldBasedHeaderExtractor forType(Class<? extends FieldBasedHeader> header){
        return new FieldBasedHeaderExtractor()
    }

}