@SuppressWarnings("unchecked")
  public static <K, V> ImmutableSetMultimap<K, V> of() {
    return (ImmutableSetMultimap<K, V>) EmptyImmutableSetMultimap.INSTANCE;
  }

  /** Returns an immutable multimap containing a single entry. */
  public static <K, V> ImmutableSetMultimap<K, V> of(K k1, V v1) {
    ImmutableSetMultimap.Builder<K, V> builder = ImmutableSetMultimap.builder();
    builder.put(k1, v1);
    return builder.build();

  @SuppressWarnings("unchecked")
  public static <K, V> ImmutableSetMultimap<K, V> of() {
    return (ImmutableSetMultimap<K, V>) EmptyImmutableSetMultimap.INSTANCE;
  }

  /** Returns an immutable multimap containing a single entry. */
  public static <K, V> ImmutableSetMultimap<K, V> of(K k1, V v1) {
    ImmutableSetMultimap.Builder<K, V> builder = ImmutableSetMultimap.builder();
    builder.put(k1, v1);
    return builder.build();

    assertEquals(ImmutableSetMultimap.of(1, "one"), ImmutableSetMultimap.of("one", 1).inverse());
    assertEquals(
        ImmutableSetMultimap.of(1, "one", 2, "two"),
        ImmutableSetMultimap.of("one", 1, "two", 2).inverse());
    assertEquals(
        ImmutableSetMultimap.of('o', "of", 'f', "of", 't', "to", 'o', "to"),
        ImmutableSetMultimap.of("of", 'o', "of", 'f', "to", 't', "to", 'o').inverse());
  }

  }

  // TODO: test ImmutableMultimap builder and factory methods

  public void testCopyOf() {
    ImmutableSetMultimap<String, String> setMultimap = ImmutableSetMultimap.of("k1", "v1");
    ImmutableMultimap<String, String> setMultimapCopy = ImmutableMultimap.copyOf(setMultimap);
    assertWithMessage("copyOf(ImmutableSetMultimap) should not create a new instance")
        .that(setMultimapCopy)
        .isSameInstanceAs(setMultimap);

  // cached so that this.multimapView().inverse() only computes inverse once
  private transient @Nullable ImmutableSetMultimap<K, V> multimapView;

  public ImmutableSetMultimap<K, V> asMultimap() {
    ImmutableSetMultimap<K, V> result = multimapView;
    return (result == null)
        ? (multimapView =
            new ImmutableSetMultimap<K, V>(new MapViewOfValuesAsSingletonSets(), size(), null))
        : result;
  }

        }
      } finally {
        monitor.leave();
      }
    }

    ImmutableSetMultimap<State, Service> servicesByState() {
      ImmutableSetMultimap.Builder<State, Service> builder = ImmutableSetMultimap.builder();
      monitor.enter();
      try {
        for (Entry<State, Service> entry : servicesByState.entries()) {

    assertThat(unmod).isNotSameInstanceAs(mod);
    assertThat(Multimaps.unmodifiableSetMultimap(unmod)).isSameInstanceAs(unmod);
    ImmutableSetMultimap<String, Integer> immutable =
        ImmutableSetMultimap.of("a", 1, "b", 2, "a", 3);
    assertThat(Multimaps.unmodifiableSetMultimap(immutable)).isSameInstanceAs(immutable);

  @LazyInit private transient @Nullable ImmutableSetMultimap<K, V> multimapView;

  /**
   * Returns a multimap view of the map.
   *
   * @since 14.0
   */
  public ImmutableSetMultimap<K, V> asMultimap() {
    if (isEmpty()) {
      return ImmutableSetMultimap.of();
    }
    ImmutableSetMultimap<K, V> result = multimapView;
    return (result == null)

import com.google.common.collect.ImmutableMultimap;
import com.google.common.collect.ImmutableMultiset;
import com.google.common.collect.ImmutableSet;
import com.google.common.collect.ImmutableSetMultimap;
import com.google.common.collect.ImmutableSortedMap;
import com.google.common.collect.ImmutableSortedMultiset;
import com.google.common.collect.ImmutableSortedSet;
import com.google.common.collect.ImmutableTable;

  @LazyInit private transient @Nullable ImmutableSetMultimap<K, V> multimapView;

  /**
   * Returns a multimap view of the map.
   *
   * @since 14.0
   */
  public ImmutableSetMultimap<K, V> asMultimap() {
    if (isEmpty()) {
      return ImmutableSetMultimap.of();
    }
    ImmutableSetMultimap<K, V> result = multimapView;
    return (result == null)