private static void moveSubClassImplementsToExtends(PsiClass oldInterface, Collection<PsiClass> inheritors) {
    for (PsiClass inheritor : inheritors) {
      final PsiReferenceList implementsList = inheritor.getImplementsList();
      final PsiReferenceList extendsList = inheritor.getExtendsList();
      if (implementsList != null) {
        moveReference(implementsList, extendsList, oldInterface);
      }
    }
  }
private static void moveSubClassImplementsToExtends(PsiClass oldInterface, Collection<PsiClass> inheritors)