@Override
  public @NotNull PsiJavaCodeReferenceElement createPackageReferenceElement(@NotNull PsiPackage aPackage) throws IncorrectOperationException {
    if (aPackage.getQualifiedName().isEmpty()) {
      throw new IncorrectOperationException("Cannot create reference to default package.");
    }
    return new LightPackageReference(myManager, aPackage);
  }
@Override
  public @NotNull PsiJavaCodeReferenceElement createPackageReferenceElement(@NotNull PsiPackage aPackage)