set.addAll(set1);
        set.addAll(set2);
        return set;
      }

      @Override
      @SuppressWarnings({"nullness", "unchecked"}) // see supertype
      public ImmutableSet<@NonNull E> immutableCopy() {
        ImmutableSet.Builder<@NonNull E> builder =
            new ImmutableSet.Builder<@NonNull E>()
                .addAll((Iterable<@NonNull E>) set1)

        Set<String> exportedPackages = new HashSet<>(coreEntry.getExportedPackages());
        for (CoreExtensionEntry extension : extensions) {
            exportedArtifacts.addAll(extension.getExportedArtifacts());
            exportedPackages.addAll(extension.getExportedPackages());
        }

        final CoreExports exports = new CoreExports(containerRealm, exportedArtifacts, exportedPackages);

    assertEquals(nestingDepth, Iterators.size(iterator));
  }

  public void testAddAllWithEmptyIterator() {
    List<String> alreadyThere = Lists.newArrayList("already", "there");

    boolean changed = Iterators.addAll(alreadyThere, Iterators.<String>emptyIterator());
    assertThat(alreadyThere).containsExactly("already", "there").inOrder();
    assertFalse(changed);
  }

  public void testAddAllToList() {

    @Override
    public boolean add(E e) {
      synchronized (mutex) {
        return delegate().add(e);
      }
    }

    @Override
    public boolean addAll(Collection<? extends E> c) {
      synchronized (mutex) {
        return delegate().addAll(c);
      }
    }

    @Override
    public void clear() {
      synchronized (mutex) {
        delegate().clear();
      }
    }

    @Override
    public boolean add(E e) {
      synchronized (mutex) {
        return delegate().add(e);
      }
    }

    @Override
    public boolean addAll(Collection<? extends E> c) {
      synchronized (mutex) {
        return delegate().addAll(c);
      }
    }

    @Override
    public void clear() {
      synchronized (mutex) {
        delegate().clear();
      }
    }

    assertEquals(nestingDepth, Iterators.size(iterator));
  }

  public void testAddAllWithEmptyIterator() {
    List<String> alreadyThere = Lists.newArrayList("already", "there");

    boolean changed = Iterators.addAll(alreadyThere, Iterators.<String>emptyIterator());
    assertThat(alreadyThere).containsExactly("already", "there").inOrder();
    assertFalse(changed);
  }

  public void testAddAllToList() {

                importResult = build(importRequest, importIds);
            } catch (ModelBuildingException e) {
                problems.addAll(e.getProblems());
                return null;
            }

            problems.addAll(importResult.getProblems());

            importModel = importResult.getEffectiveModel();
        }

    // If we're set to a default port, unset it in case of a scheme change.
    result.port = if (port != defaultPort(scheme)) port else -1
    result.encodedPathSegments.clear()
    result.encodedPathSegments.addAll(encodedPathSegments)
    result.encodedQuery(encodedQuery)
    result.encodedFragment = encodedFragment
    return result
  }

  /**

        final String key = ComponentUtil.getVirtualHostHelper().getVirtualHostKey();
        if (StringUtil.isNotBlank(key)) {
            tags = ArrayUtils.addAll(tags, key);
        }
        final String[] fields = request.getParameterValues("field");

        final PopularWordHelper popularWordHelper = ComponentUtil.getPopularWordHelper();

        } catch (final OpenSearchException e) {
            throw new SearchEngineClientException("Failed to process a ping request.", e);
        }
    }

    public BulkResponse addAll(final String index, final List<Map<String, Object>> docList,
            final BiConsumer<Map<String, Object>, IndexRequestBuilder> options) {
        final FessConfig fessConfig = ComponentUtil.getFessConfig();