public class MultisetSerializationTester<E> extends AbstractMultisetTester<E> {
  @CollectionFeature.Require(SERIALIZABLE_INCLUDING_VIEWS)
  public void testEntrySetSerialization() {
    Set<Multiset.Entry<E>> expected = getMultiset().entrySet();
    assertEquals(expected, SerializableTester.reserialize(expected));
  }

  @CollectionFeature.Require(SERIALIZABLE_INCLUDING_VIEWS)
  public void testElementSetSerialization() {

    ImmutableSet<Entry<K, V>> result = entries;
    return result == null ? (entries = new EntrySet<>(this)) : result;
  }

  private static final class EntrySet<K, V> extends ImmutableSet<Entry<K, V>> {
    @Weak private final transient ImmutableSetMultimap<K, V> multimap;

    EntrySet(ImmutableSetMultimap<K, V> multimap) {
      this.multimap = multimap;
    }

    @Override

        return of();
      case 1:
        Entry<? extends K, ? extends V> entry = getOnlyElement(map.entrySet());
        return ImmutableMap.of(entry.getKey(), entry.getValue());
      default:
        Map<K, V> orderPreservingCopy = Maps.newLinkedHashMap();
        for (Entry<? extends K, ? extends V> e : map.entrySet()) {
          orderPreservingCopy.put(checkNotNull(e.getKey()), checkNotNull(e.getValue()));
        }

    assertEquals(2, keys.count(k0()));
    assertEquals(1, keys.count(k1()));
    assertEquals(3, keys.size());
    assertContainsAllOf(keys, k0(), k1());
    assertContainsAllOf(
        keys.entrySet(), Multisets.immutableEntry(k0(), 2), Multisets.immutableEntry(k1(), 1));
  }

  @MapFeature.Require(ALLOWS_NULL_KEY_QUERIES)
  public void testKeysCountAbsentNullKey() {
    assertEquals(0, multimap().keys().count(null));

   * href="https://github.com/openjdk/jdk/blob/c25c4896ad9ef031e3cddec493aef66ff87c48a7/src/java.base/share/classes/java/util/concurrent/ConcurrentHashMap.java#L4830">{@code
   * ConcurrentHashMap} support for {@code entrySet().add()}</a>.
   */
  @J2ktIncompatible
  @GwtIncompatible // reflection
  public static Method getAddAllUnsupportedNonePresentMethod() {

        .addEqualityGroup(getMultiset())
        .addEqualityGroup(getSubjectGenerator().create())
        .testEquals();
  }

  public void testHashCodeMatchesEntrySet() {
    assertEquals(getMultiset().entrySet().hashCode(), getMultiset().hashCode());
  }

  @CollectionSize.Require(absent = ZERO)
  @CollectionFeature.Require(ALLOWS_NULL_VALUES)
  public void testEqualsMultisetWithNullValue() {
    new EqualsTester()

        multimap.putAll("cat", asList(12, 13, 14));
        return multimap.asMap().entrySet().iterator();
      }

      @Override
      protected void verify(List<Entry<String, Collection<Integer>>> elements) {
        assertEquals(new HashSet<>(elements), multimap.asMap().entrySet());
      }
    }.test();
  }

    // Test asMap().entrySet()
    assertSetIsUnmodifiable(
        multimap.asMap().entrySet(), immutableEntry(sampleKey, sampleValueAsCollection));

    // Test #values()

    assertMultimapRemainsUnmodified(multimap, originalEntries);
    if (!multimap.isEmpty()) {
      Collection<V> values = multimap.asMap().entrySet().iterator().next().getValue();

  }

  public void testToImmutableMultiset() {
    BiPredicate<ImmutableMultiset<String>, ImmutableMultiset<String>> equivalence =
        (ms1, ms2) -> ms1.equals(ms2) && ms1.entrySet().asList().equals(ms2.entrySet().asList());
    CollectorTester.of(ImmutableMultiset.<String>toImmutableMultiset(), equivalence)
        .expectCollects(ImmutableMultiset.of())
        .expectCollects(

      assertTrue(multimap.containsEntry(entry.getKey(), entry.getValue()));
      size++;
    }
    assertEquals(expectedSize, size);

    int size2 = 0;
    for (Entry<K, Collection<V>> entry2 : multimap.asMap().entrySet()) {
      size2 += entry2.getValue().size();
    }
    assertEquals(expectedSize, size2);
  }

  @CollectionSize.Require(ZERO)
  public void testIsEmptyYes() {
    assertTrue(multimap().isEmpty());
  }