*
   * // impossible for a non-String to be in the intersection
   * SuppressWarnings("unchecked")
   * Set<String> badStrings = (Set) Sets.intersection(
   *     aFewBadObjects, manyBadStrings);
   * }
   *
   * <p>This is unfortunate, but should come up only very rarely.
   */
  public static <E extends @Nullable Object> SetView<E> intersection(Set<E> set1, Set<?> set2) {
    checkNotNull(set1, "set1");

	if dnsBuckets != nil {
		for _, bucket := range buckets {
			bucketsSet.Add(bucket)
			r, ok := dnsBuckets[bucket]
			if !ok {
				bucketsToBeUpdated.Add(bucket)
				continue
			}
			if !globalDomainIPs.Intersection(set.CreateStringSet(getHostsSlice(r)...)).IsEmpty() {
				if globalDomainIPs.Difference(set.CreateStringSet(getHostsSlice(r)...)).IsEmpty() && !domainMissing {
					// No difference in terms of domainIPs and nothing

				err = errNoSuchPolicy
				return
			}
		}
		newPolicySet = existingPolicySet.Union(policiesToUpdate)
	} else {
		// policies to detach => inputPolicies ∩ existing (intersection)
		policiesToUpdate = policiesToUpdate.Intersection(existingPolicySet)
		newPolicySet = existingPolicySet.Difference(policiesToUpdate)
	}
	// We return an error if the requested policy update will have no effect.