private static @NotNull List<String> getInheritors(@NotNull PsiClass from, @NotNull PsiClass to) {
    List<String> candidates = new ArrayList<>();
    String fromName = getClassName(from);
    if (fromName != null) {
      candidates.add(fromName);
    }
    for (PsiClass cls : InheritanceUtil.getSuperClasses(from)) {
      if (cls.isInheritor(to, true)) {
        String name = getClassName(cls);
        if (name == null) continue;
        candidates.add(name);
      }
    }
    return candidates;
  }
private static @NotNull List<String> getInheritors(@NotNull PsiClass from, @NotNull PsiClass to)