List<@Nullable String> listWithNulls = asList("a", null, "b");
      assertThrows(NullPointerException.class, () -> builder.addAll((List<String>) listWithNulls));
    }

    {
      ImmutableMultiset.Builder<String> builder = ImmutableMultiset.builder();
      Multiset<@Nullable String> multisetWithNull =
          LinkedHashMultiset.create(Arrays.<@Nullable String>asList("a", null, "b"));

import org.jspecify.annotations.Nullable;

/**
 * Tests for {@code GeneralRange}.
 *
 * @author Louis Wasserman
 */
@GwtCompatible
@NullMarked
public class GeneralRangeTest extends TestCase {
  private static final Ordering<@Nullable Integer> ORDERING =
      Ordering.<Integer>natural().<Integer>nullsFirst();

  private static final List<@Nullable Integer> IN_ORDER_VALUES =

   */
  public static <T extends @Nullable Object> Iterable<List<@Nullable T>> paddedPartition(
      Iterable<T> iterable, int size) {
    checkNotNull(iterable);
    checkArgument(size > 0);
    return new FluentIterable<List<@Nullable T>>() {
      @Override
      public Iterator<List<@Nullable T>> iterator() {
        return Iterators.paddedPartition(iterable.iterator(), size);

    int nextSegmentIndex;
    int nextTableIndex;
    @Nullable Segment<K, V> currentSegment;
    @Nullable AtomicReferenceArray<ReferenceEntry<K, V>> currentTable;
    @Nullable ReferenceEntry<K, V> nextEntry;
    @Nullable WriteThroughEntry nextExternal;
    @Nullable WriteThroughEntry lastReturned;

    HashIterator() {
      nextSegmentIndex = segments.length - 1;

  @Override
  public @Nullable V remove(@Nullable Object key) {
    Map<K, V> delegate = delegateOrNull();
    if (delegate != null) {
      return delegate.remove(key);
    }
    Object oldValue = removeHelper(key);
    return (oldValue == NOT_FOUND) ? null : (V) oldValue;
  }

  private @Nullable Object removeHelper(@Nullable Object key) {
    if (needsAllocArrays()) {

   */

  static final class Node<K extends @Nullable Object, V extends @Nullable Object>
      extends SimpleEntry<K, V> {
    @Nullable Node<K, V> next; // the next node (with any key)
    @Weak @Nullable Node<K, V> previous; // the previous node (with any key)
    @Nullable Node<K, V> nextSibling; // the next node with the same key
    @Weak @Nullable Node<K, V> previousSibling; // the previous node with the same key

   * not have been inserted consecutively.
   */
  private final @Nullable List<NodeConnection<N>> orderedNodeConnections;

  private int predecessorCount;
  private int successorCount;

  private DirectedGraphConnections(
      Map<N, Object> adjacentNodeValues,
      @Nullable List<NodeConnection<N>> orderedNodeConnections,
      int predecessorCount,
      int successorCount) {

  @VisibleForTesting final transient @Nullable Object[] array;
  private final transient int size;

  RegularImmutableList(@Nullable Object[] array, int size) {
    this.array = array;
    this.size = size;
  }

  @Override
  public int size() {
    return size;
  }

  @Override
  boolean isPartialView() {
    return false;
  }

  @Override
  @Nullable Object[] internalArray() {
    return array;

import java.util.Iterator;
import java.util.Map.Entry;
import java.util.Objects;
import org.jspecify.annotations.Nullable;

/**
 * Implementation for {@link FilteredMultimap#values()}.
 *
 * @author Louis Wasserman
 */
@GwtCompatible
final class FilteredMultimapValues<K extends @Nullable Object, V extends @Nullable Object>
    extends AbstractCollection<V> {
  @Weak private final FilteredMultimap<K, V> multimap;

  @CanIgnoreReturnValue
  @Override
  public @Nullable V putIfAbsent(K key, V value) {
    return delegate().putIfAbsent(key, value);
  }

  @CanIgnoreReturnValue
  @Override
  public boolean remove(@Nullable Object key, @Nullable Object value) {
    return delegate().remove(key, value);
  }

  @CanIgnoreReturnValue
  @Override
  public @Nullable V replace(K key, V value) {