* @return a set of entries representing the data of this multiset
   */
  Set<Entry<E>> entrySet();

  /**
   * An unmodifiable element-count pair for a multiset. The {@link Multiset#entrySet} method returns
   * a view of the multiset whose elements are of this class. A multiset implementation may return
   * Entry instances that are either live "read-through" views to the Multiset, or immutable

   * @return a set of entries representing the data of this multiset
   */
  Set<Entry<E>> entrySet();

  /**
   * An unmodifiable element-count pair for a multiset. The {@link Multiset#entrySet} method returns
   * a view of the multiset whose elements are of this class. A multiset implementation may return
   * Entry instances that are either live "read-through" views to the Multiset, or immutable

  }

  public void testCount_wrongType() {
    assertEquals(
        "multiset.count(wrongType) didn't return 0", 0, getMultiset().count(WrongType.VALUE));
  }

  /**
   * Returns {@link Method} instances for the read tests that assume multisets support duplicates so
   * that the test of {@code Multisets.forSet()} can suppress them.
   */
  @J2ktIncompatible
  @GwtIncompatible // reflection

  }

  @CollectionSize.Require(ONE)
  @CollectionFeature.Require(SUPPORTS_ITERATOR_REMOVE)
  public void testKeysEntrySetIteratorRemove() {
    Multiset<K> keys = multimap().keys();
    Iterator<Multiset.Entry<K>> itr = keys.entrySet().iterator();
    assertEquals(Multisets.immutableEntry(k0(), 1), itr.next());
    itr.remove();
    assertTrue(multimap().isEmpty());
  }

  @CollectionSize.Require(SEVERAL)

@GwtCompatible
public enum MultisetFeature implements Feature<Multiset> {
  /**
   * Indicates that elements from {@code Multiset.entrySet()} update to reflect changes in the
   * backing multiset.
   */
  ENTRIES_ARE_VIEWS;

  @Override
  public Set<Feature<? super Multiset>> getImpliedFeatures() {
    return emptySet();
  }

  @Retention(RetentionPolicy.RUNTIME)
  @Inherited

    Multiset<String> multiset = HashMultiset.create(asList("a", "b", "a"));
    Multiset<String> toRetain = HashMultiset.create();
    assertTrue(Multisets.retainOccurrences(multiset, toRetain));
    assertTrue(multiset.isEmpty());
  }

  public void testRetainOccurrences() {
    Multiset<String> multiset = TreeMultiset.create(asList("a", "b", "a", "c"));

          Multisets.immutableEntry(samples.e0(), 3),
          Multisets.immutableEntry(samples.e1(), 4),
          Multisets.immutableEntry(samples.e2(), 1),
          Multisets.immutableEntry(samples.e3(), 5),
          Multisets.immutableEntry(samples.e4(), 2));
    }

    @Override
    public Set<Multiset.Entry<E>> create(Object... entries) {
      List<Object> contents = new ArrayList<>();

  }

  public void testEmptyRangeSubMultiset(SortedMultiset<E> multiset) {
    assertTrue(multiset.isEmpty());
    assertEquals(0, multiset.size());
    assertEquals(0, multiset.toArray().length);
    assertTrue(multiset.entrySet().isEmpty());
    assertFalse(multiset.iterator().hasNext());
    assertEquals(0, multiset.entrySet().size());
    assertEquals(0, multiset.entrySet().toArray().length);

    Multiset<String> multiset = HashMultiset.create(50);
    multiset.add("foo", 2);
    multiset.add("bar");
    assertEquals(3, multiset.size());
    assertEquals(2, multiset.count("foo"));
  }

  public void testCreateFromIterable() {
    Multiset<String> multiset = HashMultiset.create(asList("foo", "bar", "foo"));
    assertEquals(3, multiset.size());
    assertEquals(2, multiset.count("foo"));
  }

  @J2ktIncompatible

  private static class MutateTask implements Callable<int[]> {
    private final ConcurrentHashMultiset<String> multiset;
    private final ImmutableList<String> keys;
    private final Random random = new Random();

    private MutateTask(ConcurrentHashMultiset<String> multiset, ImmutableList<String> keys) {
      this.multiset = multiset;
      this.keys = keys;
    }

    @Override
    public int[] call() throws Exception {