Multimap<String, Integer> multimap = createMultimap();
    Multimap<String, Integer> hashMultimap = HashMultimap.create();
    hashMultimap.putAll("foo", Arrays.asList(1, 3));
    hashMultimap.put("bar", 2);

    new EqualsTester()
        .addEqualityGroup(
            multimap,
            createMultimap(),
            hashMultimap,
            ImmutableSetMultimap.<String, Integer>builder()
                .put("bar", 2)

    Multimap<String, Integer> multimap = createMultimap();
    Multimap<String, Integer> hashMultimap = HashMultimap.create();
    hashMultimap.putAll("foo", Arrays.asList(1, 3));
    hashMultimap.put("bar", 2);

    new EqualsTester()
        .addEqualityGroup(
            multimap,
            createMultimap(),
            hashMultimap,
            ImmutableSetMultimap.<String, Integer>builder()
                .put("bar", 2)

  public void testUnmodifiableHashMultimap() {
    checkUnmodifiableMultimap(HashMultimap.<@Nullable String, @Nullable Integer>create(), false);
  }

  @J2ktIncompatible
  @GwtIncompatible // SerializableTester
  public void testSerializingUnmodifiableHashMultimap() {
    Multimap<String, Integer> unmodifiable =
        prepareUnmodifiableTests(HashMultimap.<String, Integer>create(), false, null, null);

  public void testUnmodifiableHashMultimap() {
    checkUnmodifiableMultimap(HashMultimap.<@Nullable String, @Nullable Integer>create(), false);
  }

  @J2ktIncompatible
  @GwtIncompatible // SerializableTester
  public void testSerializingUnmodifiableHashMultimap() {
    Multimap<String, Integer> unmodifiable =
        prepareUnmodifiableTests(HashMultimap.<String, Integer>create(), false, null, null);

    return generateLinkedHashMultimap(key, value);
  }

  @Generates
  static <K, V> HashMultimap<K, V> generateHashMultimap(@Nullable K key, @Nullable V value) {
    HashMultimap<K, V> multimap = HashMultimap.create();
    multimap.put(key, value);
    return multimap;
  }

  @Generates
  static <K, V> LinkedHashMultimap<K, V> generateLinkedHashMultimap(

    return generateLinkedHashMultimap(key, value);
  }

  @Generates
  static <K, V> HashMultimap<K, V> generateHashMultimap(@Nullable K key, @Nullable V value) {
    HashMultimap<K, V> multimap = HashMultimap.create();
    multimap.put(key, value);
    return multimap;
  }

  @Generates
  static <K, V> LinkedHashMultimap<K, V> generateLinkedHashMultimap(

  }

  /** Test that creating one TreeMultimap from a non-TreeMultimap results in natural ordering. */
  public void testCreateFromHashMultimap() {
    Multimap<Double, Double> hash = HashMultimap.create();
    hash.put(1.0, 2.0);
    hash.put(2.0, 3.0);
    hash.put(3.0, 4.0);
    hash.put(4.0, 5.0);

    TreeMultimap<Double, Double> copyFromHash = TreeMultimap.create(hash);

  }

  /** Test that creating one TreeMultimap from a non-TreeMultimap results in natural ordering. */
  public void testCreateFromHashMultimap() {
    Multimap<Double, Double> hash = HashMultimap.create();
    hash.put(1.0, 2.0);
    hash.put(2.0, 3.0);
    hash.put(3.0, 4.0);
    hash.put(4.0, 5.0);

    TreeMultimap<Double, Double> copyFromHash = TreeMultimap.create(hash);

   * #synchronizedMultimap}.
   *
   * <p>Call this method only when the simpler methods {@link ArrayListMultimap#create()}, {@link
   * HashMultimap#create()}, {@link LinkedHashMultimap#create()}, {@link
   * LinkedListMultimap#create()}, {@link TreeMultimap#create()}, and {@link
   * TreeMultimap#create(Comparator, Comparator)} won't suffice.
   *