private static final @Nullable String NE = null;

  private static <E extends @Nullable Object> Entry<E> entry(E element, int count) {
    return Multisets.immutableEntry(element, count);
  }

  private static <E extends @Nullable Object> Entry<E> control(E element, int count) {
    return HashMultiset.create(nCopies(count, element)).entrySet().iterator().next();
  }

  public void testToString() {

// (m[key]) from the map. If m is nil or there is no such element, delete
// is a no-op.
func delete(m map[Type]Type1, key Type)

// The len built-in function returns the length of v, according to its type:
//
//   - Array: the number of elements in v.
//   - Pointer to array: the number of elements in *v (even if v is nil).

              public Collection<String> create(String[] elements) {
                // TODO: MinimalCollection should perhaps throw
                for (Object element : elements) {
                  if (element == null) {
                    throw new NullPointerException();
                  }
                }
                return MinimalCollection.of(elements);
              }
            })

    assertTrue(
        "multiset.entrySet.remove(presentEntry) returned false",
        getMultiset().entrySet().remove(Multisets.immutableEntry(e0(), 1)));
    assertFalse("multiset contains element after removing its entry", getMultiset().contains(e0()));
  }

  @CollectionSize.Require(absent = ZERO)
  @CollectionFeature.Require(SUPPORTS_REMOVE)
  public void testEntrySet_removeAbsent() {
    assertFalse(

 *
 * List<String> list = ...;
 * Set<String> set = ...;
 * Map<String, Object> map = ...;
 * for (String element : iterable(list, set, map.keySet())) {
 *     ...
 * }
 * </pre>
 *
 * @author koichik
 * @param <E> the element type
 */
public class MultiIterator<E> implements Iterator<E> {

    /** Array of {@link Iterator}s. */
    protected final Iterator<E>[] iterators;

  /** Test an empty collection. */
  ZERO(0),
  /** Test a one-element collection. */
  ONE(1),
  /** Test a three-element collection. */
  SEVERAL(3),
  /*
   * TODO: add VERY_LARGE, noting that we currently assume that the fourth
   * sample element is not in any collection
   */

  ANY(ZERO, ONE, SEVERAL);

  private final Set<Feature<? super Collection>> implied;

  /** Test an empty collection. */
  ZERO(0),
  /** Test a one-element collection. */
  ONE(1),
  /** Test a three-element collection. */
  SEVERAL(3),
  /*
   * TODO: add VERY_LARGE, noting that we currently assume that the fourth
   * sample element is not in any collection
   */

  ANY(ZERO, ONE, SEVERAL);

  private final Set<Feature<? super Collection>> implied;

    @Override
    public boolean add(final Map<String, Object> e) {
        return parent.add(e);
    }

    @Override
    public void add(final int index, final Map<String, Object> element) {
        parent.add(index, element);
    }

    @Override
    public boolean addAll(final Collection<? extends Map<String, Object>> c) {
        return parent.addAll(c);
    }

    @Override

              public Collection<String> create(String[] elements) {
                // TODO: MinimalCollection should perhaps throw
                for (Object element : elements) {
                  if (element == null) {
                    throw new NullPointerException();
                  }
                }
                return MinimalCollection.of(elements);
              }
            })

   * support concurrent multisets whose content may change while the method is running.
   *
   * <p>The serialized output consists of the number of distinct elements, the first element, its
   * count, the second element, its count, and so on.
   */
  static <E extends @Nullable Object> void writeMultiset(
      Multiset<E> multiset, ObjectOutputStream stream) throws IOException {