/**
   * Helper method to create an array of the appropriate type used by this generator. The returned
   * array will contain only nulls.
   */
  E[] createArray(int length);

  /**
   * Returns the iteration ordering of elements, given the order in which they were added to the
   * container. This method may return the original list unchanged, the original list modified in
   * place, or a different list.
   *

                new TestStringSetGenerator() {
                  @Override
                  protected Set<String> create(String[] elements) {
                    SafeTreeSet<String> set = new SafeTreeSet<>(Ordering.natural().nullsFirst());
                    Collections.addAll(set, elements);
                    return new StandardImplForwardingNavigableSet<>(set);
                  }

                  @Override

 * a {@link SortedSet}. It cannot hold duplicate key-value pairs; adding a key-value pair that's
 * already in the multimap has no effect. This interface does not specify the ordering of the
 * multimap's keys. See the {@link Multimap} documentation for information common to all multimaps.
 *
 * <p>The {@link #get}, {@link #removeAll}, and {@link #replaceValues} methods each return a {@link

   * Returns an {@code ImmutableList} containing all of the elements from this {@code
   * FluentIterable} in the order specified by {@code comparator}. To produce an {@code
   * ImmutableList} sorted by its natural ordering, use {@code toSortedList(Ordering.natural())}.
   *
   * <p><b>{@code Stream} equivalent:</b> pass {@link ImmutableList#toImmutableList} to {@code
   * stream.sorted(comparator).collect()}.
   *

 * or its views. The {@link #erase} and {@link #eraseAll} methods may be used instead.
 *
 * <p>The ordering of the row and column keys provided when the table is constructed determines the
 * iteration ordering across rows and columns in the table's views. None of the view iterators
 * support {@link Iterator#remove}. If the table is modified after an iterator is created, the

  protected abstract Multiset<AnEnum> create(AnEnum[] elements);

  @Override
  public AnEnum[] createArray(int length) {
    return new AnEnum[length];
  }

  /** Sorts the enums according to their natural ordering. */
  /*
   * While the current implementation returns `this`, that's not something we mean to guarantee.
   * Callers of TestContainerGenerator.order need to be prepared for implementations to return a new
   * collection.

  @Nullable private transient Comparator<? super E> comparator;

  @Override
  public Comparator<? super E> comparator() {
    Comparator<? super E> result = comparator;
    if (result == null) {
      return comparator = Ordering.from(forwardMultiset().comparator()).reverse();
    }
    return result;
  }

  @Nullable private transient SortedSet<E> elementSet;

  @Override
  public SortedSet<E> elementSet() {

    private final SortedSet<String> delegate = Sets.newTreeSet(Ordering.natural());

    @Override
    protected SortedSet<String> delegate() {
      return delegate;
    }
  }

  private static class NonNavigableSortedMap extends ForwardingSortedMap<String, String> {

    private final SortedMap<String, String> delegate = new SafeTreeMap<>(Ordering.natural());

    @Override

 * or its views. The {@link #erase} and {@link #eraseAll} methods may be used instead.
 *
 * <p>The ordering of the row and column keys provided when the table is constructed determines the
 * iteration ordering across rows and columns in the table's views. None of the view iterators
 * support {@link Iterator#remove}. If the table is modified after an iterator is created, the

@SuppressWarnings("JUnit4ClassUsedInJUnit3")
public class ListMultimapPutTester<K, V> extends AbstractListMultimapTester<K, V> {
  // MultimapPutTester tests non-duplicate values, but ignores ordering

  @MapFeature.Require(SUPPORTS_PUT)
  public void testPutAddsValueAtEnd() {
    for (K key : sampleKeys()) {
      for (V value : sampleValues()) {
        resetContainer();