if (cookies == null) cookies = mutableListOf()
          cookies.addAll(decodeHeaderAsJavaNetCookies(url, header))
        }
      }
    }

    return if (cookies != null) {
      Collections.unmodifiableList(cookies)
    } else {
      emptyList()
    }
  }

  /**
   * Convert a request header to OkHttp's cookies via [HttpCookie]. That extra step handles

        if (!ArtifactIdUtils.equalsVersionlessId(pomArtifact, projectArtifact)) {
            result.add(session.getArtifact(projectArtifact));
        }
        return Collections.unmodifiableList(result);
    }

    @Nonnull
    @Override
    public Packaging getPackaging() {
        return packaging;
    }

    @Nonnull
    @Override
    public Model getModel() {

        this.projectProperties = unmodifiable(projectProperties);

        return this;
    }

    private static List<String> unmodifiable(List<String> list) {
        return list != null ? Collections.unmodifiableList(list) : Collections.emptyList();
    }

    private static Map<String, String> unmodifiable(Map<String, String> map) {
        return map != null ? Collections.unmodifiableMap(map) : Collections.emptyMap();
    }

                .values()
                .stream()
                .map(MavenProject::getVersion)
                .collect(Collectors.collectingAndThen(Collectors.toList(), Collections::unmodifiableList));
        if (!versions.isEmpty()) {
            return versions;
        }
        return getAllProjects()
                .getOrDefault(artifact.getGroupId(), Collections.emptyMap())

    new IteratorTester<T>(
        list.size() * 2 + 2, UNMODIFIABLE, list, IteratorTester.KnownOrder.KNOWN_ORDER) {
      @Override
      protected Iterator<T> newTargetIterator() {
        Iterator<T> iterator = Collections.unmodifiableList(list).iterator();
        return Iterators.peekingIterator(iterator);
      }
    }.test();
  }

  public void testPeekingIteratorBehavesLikeIteratorOnEmptyIterable() {

    new IteratorTester<T>(
        list.size() * 2 + 2, UNMODIFIABLE, list, IteratorTester.KnownOrder.KNOWN_ORDER) {
      @Override
      protected Iterator<T> newTargetIterator() {
        Iterator<T> iterator = Collections.unmodifiableList(list).iterator();
        return Iterators.peekingIterator(iterator);
      }
    }.test();
  }

  public void testPeekingIteratorBehavesLikeIteratorOnEmptyIterable() {

    T[] topK = Arrays.copyOf(castBuffer, bufferSize);
    // we have to support null elements, so no ImmutableList for us
    return Collections.unmodifiableList(Arrays.asList(topK));
  }

        this.resolver = resolver;
        this.remoteRepositoryManager = remoteRepositoryManager;
        this.pomRepositories = new ArrayList<>();
        this.externalRepositories = Collections.unmodifiableList(new ArrayList<>(repositories));
        this.repositories = new ArrayList<>();
        this.repositories.addAll(externalRepositories);
        this.repositoryMerging = repositoryMerging;

        return null;
      } else if (unfiltered instanceof SetMultimap) {
        return Collections.unmodifiableSet(Sets.newLinkedHashSet(result));
      } else {
        return Collections.unmodifiableList(result);
      }
    }

    @Override
    Set<K> createKeySet() {
      @WeakOuter
      class KeySetImpl extends Maps.KeySet<K, Collection<V>> {
        KeySetImpl() {

        List<Restriction> restrictions;

        if (r1.isEmpty() || r2.isEmpty()) {
            restrictions = Collections.emptyList();
        } else {
            restrictions = Collections.unmodifiableList(intersection(r1, r2));
        }

        ArtifactVersion version = null;
        if (restrictions.size() > 0) {
            for (Restriction r : restrictions) {