public static @Nullable Set<TargetType> getAnnotationTargets(@NotNull PsiClass annotationType) {
    if (!annotationType.isAnnotationType()) return null;
    PsiModifierList modifierList = annotationType.getModifierList();
    if (modifierList == null) return null;

    return CachedValuesManager.getCachedValue(modifierList, () ->
      CachedValueProvider.Result.create(calcAnnotationTargets(modifierList), PsiModificationTracker.MODIFICATION_COUNT));
  }
public static @Nullable Set<TargetType> getAnnotationTargets(@NotNull PsiClass annotationType)