@Override
    public boolean removeAll(Collection<?> c) {
      synchronized (mutex) {
        return Iterators.removeAll(delegate().iterator(), c);
      }
    }

    @Override
    public boolean retainAll(Collection<?> c) {
      synchronized (mutex) {
        return Iterators.retainAll(delegate().iterator(), c);
      }
    }

    @Override
    public boolean removeAll(Collection<?> c) {
      synchronized (mutex) {
        return Iterators.removeAll(delegate().iterator(), c);
      }
    }

    @Override
    public boolean retainAll(Collection<?> c) {
      synchronized (mutex) {
        return Iterators.retainAll(delegate().iterator(), c);
      }
    }

      @Override
      public UnmodifiableIterator<E> iterator() {
        Iterable<E> incidentEdges =
            (selfLoopCount == 0)
                ? Iterables.concat(inEdgeMap.keySet(), outEdgeMap.keySet())
                : Sets.union(inEdgeMap.keySet(), outEdgeMap.keySet());
        return Iterators.unmodifiableIterator(incidentEdges.iterator());
      }

      @Override
      public int size() {

    resetContainer(mapEntry(k0(), v0()), mapEntry(k0(), v3()));
    Set<Entry<K, Collection<V>>> asMapEntrySet = multimap().asMap().entrySet();
    Iterator<Entry<K, Collection<V>>> asMapEntryItr = asMapEntrySet.iterator();
    asMapEntryItr.next();
    asMapEntryItr.remove();
    assertTrue(multimap().isEmpty());
  }

   * contains(). Verify that these sets are consistent with the elements of their iterator.
   */
  @CanIgnoreReturnValue
  static <T> Set<T> sanityCheckSet(Set<T> set) {
    assertThat(set).hasSize(Iterators.size(set.iterator()));
    for (Object element : set) {
      assertThat(set).contains(element);
    }
    assertThat(set).doesNotContain(new Object());

    checkNotNull(elements); // for GWT
    return (elements instanceof Collection)
        ? copyOf((Collection<? extends E>) elements)
        : copyOf(elements.iterator());
  }

  public static <E> ImmutableList<E> copyOf(Iterator<? extends E> elements) {
    return copyFromCollection(Lists.newArrayList(elements));
  }

  public static <E> ImmutableList<E> copyOf(Collection<? extends E> elements) {

         * the association between the artifacts of the same project.
         */
        for (Iterator<? extends Metadata> it = metadatas.iterator(); it.hasNext(); ) {
            Metadata metadata = it.next();
            if (metadata instanceof PluginsMetadata pluginsMetadata) {
                it.remove();

        return MutableClassToInstanceMap.this.delegate().entrySet();
      }

      @Override
      public Iterator<Entry<Class<? extends @NonNull B>, B>> iterator() {
        return new TransformedIterator<
            Entry<Class<? extends @NonNull B>, B>, Entry<Class<? extends @NonNull B>, B>>(
            delegate().iterator()) {
          @Override
          Entry<Class<? extends @NonNull B>, B> transform(

   * half of that is more awkward to arrange...
   */
  private static <T> Iterable<T> iterable(Collection<T> collection) {
    // return collection::iterator;
    return new Iterable<T>() {
      @Override
      public Iterator<T> iterator() {
        return collection.iterator();
      }
    };
  }

  public void testEquals() {
    new EqualsTester()
        .addEqualityGroup(ImmutableLongArray.of())

    for (Entry<K, V> entry : entries) {
      resetContainer();

      K key = entry.getKey();
      V value = entry.getValue();

      Iterator<Entry<K, Collection<V>>> asMapItr = multimap().asMap().entrySet().iterator();
      Collection<V> collection = null;
      while (asMapItr.hasNext()) {
        Entry<K, Collection<V>> asMapEntry = asMapItr.next();
        if (key.equals(asMapEntry.getKey())) {