extends TestFilteredMultimapGenerator<SetMultimap<String, Integer>>
      implements TestSetMultimapGenerator<String, Integer> {

    abstract SetMultimap<String, Integer> filter(SetMultimap<String, Integer> multimap);

    @Override
    public SetMultimap<String, Integer> create(Object... elements) {
      SetMultimap<String, Integer> multimap = LinkedHashMultimap.create();

    HashMultimapImpl {
      @Override
      <K extends Comparable<K>, V extends Comparable<V>> SetMultimap<K, V> create(
          Multimap<K, V> contents) {
        return HashMultimap.create(contents);
      }
    },
    LinkedHashMultimapImpl {
      @Override
      <K extends Comparable<K>, V extends Comparable<V>> SetMultimap<K, V> create(
          Multimap<K, V> contents) {
        return LinkedHashMultimap.create(contents);

   *
   * @since 16.0
   */
  public abstract static class SetMultimapBuilder<
          K0 extends @Nullable Object, V0 extends @Nullable Object>
      extends MultimapBuilder<K0, V0> {
    SetMultimapBuilder() {}

    @Override
    public abstract <K extends K0, V extends V0> SetMultimap<K, V> build();

    @Override

   *
   * @since 16.0
   */
  public abstract static class SetMultimapBuilder<
          K0 extends @Nullable Object, V0 extends @Nullable Object>
      extends MultimapBuilder<K0, V0> {
    SetMultimapBuilder() {}

    @Override
    public abstract <K extends K0, V extends V0> SetMultimap<K, V> build();

    @Override

import com.google.common.collect.Ordering;
import com.google.common.collect.PeekingIterator;
import com.google.common.collect.Range;
import com.google.common.collect.RowSortedTable;
import com.google.common.collect.SetMultimap;
import com.google.common.collect.Sets;
import com.google.common.collect.SortedMapDifference;
import com.google.common.collect.SortedMultiset;
import com.google.common.collect.SortedSetMultimap;

    suite.addTest(
        SortedSetMultimapTestSuiteBuilder.using(
                new TestStringSetMultimapGenerator() {
                  @Override
                  protected SetMultimap<String, String> create(Entry<String, String>[] entries) {
                    SetMultimap<String, String> multimap =
                        TreeMultimap.create(
                            Ordering.natural().nullsFirst(), Ordering.natural().nullsFirst());

 * ListMultimap} and {@link SetMultimap}. These take their names from the fact that the collections
 * they return from {@code get} behave like (and, of course, implement) {@link List} and {@link
 * Set}, respectively.
 *
 * <p>For example, the "presidents" code snippet above used a {@code ListMultimap}; if it had used a
 * {@code SetMultimap} instead, two presidents would have vanished, and last names might or might

  Collection<V> unmodifiableEmptyCollection() {
    // These return false, rather than throwing a UOE, on remove calls.
    return (unfiltered instanceof SetMultimap) ? emptySet() : emptyList();
  }

  @Override
  public void clear() {
    entries().clear();
  }

  @Override
  public Collection<V> get(@ParametricNullness K key) {

  Collection<V> unmodifiableEmptyCollection() {
    // These return false, rather than throwing a UOE, on remove calls.
    return (unfiltered instanceof SetMultimap) ? emptySet() : emptyList();
  }

  @Override
  public void clear() {
    entries().clear();
  }

  @Override
  public Collection<V> get(@ParametricNullness K key) {

import java.util.stream.Collector;
import java.util.stream.Stream;
import org.jspecify.annotations.Nullable;

/**
 * A {@link SetMultimap} whose contents will never change, with many other important properties
 * detailed at {@link ImmutableCollection}.
 *
 * <p><b>Warning:</b> As in all {@link SetMultimap}s, do not modify either a key <i>or a value</i>
 * of a {@code ImmutableSetMultimap} in a way that affects its {@link Object#equals} behavior.