public void testAddAtIndexConcurrentWithIteration() {
    assertThrows(
        ConcurrentModificationException.class,
        () -> {
          Iterator<E> iterator = collection.iterator();
          getList().add(0, e3());
          iterator.next();
        });
  }

  @ListFeature.Require(absent = SUPPORTS_ADD_WITH_INDEX)
  public void testAddAtIndex_unsupportedNotPresent() {

  }

  @Override
  UnmodifiableIterator<Entry<K, V>> entryIterator() {
    return new UnmodifiableIterator<Entry<K, V>>() {
      final Iterator<? extends Entry<K, ? extends ImmutableCollection<V>>> asMapItr =
          map.entrySet().iterator();
      @Nullable K currentKey = null;
      Iterator<V> valueItr = emptyIterator();

      @Override
      public boolean hasNext() {
        return valueItr.hasNext() || asMapItr.hasNext();

    offerAll(elements.iterator());
  }

  /**
   * Adds each member of {@code elements} as a candidate for the top {@code k} elements. This
   * operation takes amortized linear time in the length of {@code elements}. The iterator is
   * consumed after this operation completes.
   *
   * <p>If all input data to this {@code TopKSelector} is in a single {@code Iterator}, prefer

            putAll(map);
        }
    }

    @Override
    public String toString() {
        StringBuilder buffer = new StringBuilder("ManagedVersionMap (" + size() + " entries)\n");
        Iterator<String> iter = keySet().iterator();
        while (iter.hasNext()) {
            String key = iter.next();
            buffer.append(key).append('=').append(get(key));
            if (iter.hasNext()) {
                buffer.append('\n');

  }

  @CollectionSize.Require(ONE)
  @CollectionFeature.Require(SUPPORTS_ITERATOR_REMOVE)
  public void testKeysEntrySetIteratorRemove() {
    Multiset<K> keys = multimap().keys();
    Iterator<Multiset.Entry<K>> itr = keys.entrySet().iterator();
    assertEquals(Multisets.immutableEntry(k0(), 1), itr.next());
    itr.remove();
    assertTrue(multimap().isEmpty());
  }

  @CollectionSize.Require(SEVERAL)

    public String toString() {
        StringBuilder ret = new StringBuilder().append(proto).append(":").append(server).append("[").append(endpoint);
        if (options != null) {
            final Iterator iter = options.keySet().iterator();
            while (iter.hasNext()) {
                final Object key = iter.next();
                final Object val = options.get(key);

  }

  /**
   * Returns a sequential {@link Stream} of the remaining contents of {@code iterator}. Do not use
   * {@code iterator} directly after passing it to this method.
   */
  public static <T extends @Nullable Object> Stream<T> stream(Iterator<T> iterator) {
    return StreamSupport.stream(Spliterators.spliteratorUnknownSize(iterator, 0), false);
  }

  /**

    }

    @Override
    public Iterator<K> iterator() {
      return keySetIterator();
    }

    @Override
    public void clear() {
      CompactHashMap.this.clear();
    }
  }

  Iterator<K> keySetIterator() {
    Map<K, V> delegate = delegateOrNull();
    if (delegate != null) {
      return delegate.keySet().iterator();
    }
    return new Itr<K>() {
      @Override

    return appendTo(appendable, parts.iterator());
  }

  /**
   * Appends the string representation of each of {@code parts}, using the previously configured
   * separator between each, to {@code appendable}.
   *
   * @since 11.0
   */
  @CanIgnoreReturnValue
  public <A extends Appendable> A appendTo(A appendable, Iterator<?> parts) throws IOException {
    checkNotNull(appendable);

    map.putInstance(String.class, "test");
    assertEquals(TypeToken.of(String.class), map.entrySet().iterator().next().getKey());
    assertEquals("test", map.entrySet().iterator().next().getValue());
    assertThrows(
        UnsupportedOperationException.class, () -> map.entrySet().iterator().next().setValue(1));
  }

  public void testEntrySetToArrayMutationThrows() {
    map.putInstance(String.class, "test");