@Override
  public PsiReference @NotNull [] getReferencesByElement(@NotNull PsiElement element,
                                                         @NotNull ProcessingContext context) {
    final XmlAttributeValue attributeValue = (XmlAttributeValue)element;
    return new PsiReference[] {new JavaFXFactoryReference(attributeValue)};
  }
@Override
  public PsiReference @NotNull [] getReferencesByElement(@NotNull PsiElement element,
                                                         @NotNull ProcessingContext context)