return new Strings();
  }

  @Override
  public Set<String> create(Object... elements) {
    String[] array = new String[elements.length];
    int i = 0;
    for (Object e : elements) {
      array[i++] = (String) e;
    }
    return create(array);
  }

  protected abstract Set<String> create(String[] elements);

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

    return new Ints();
  }

  @Override
  public Set<Integer> create(Object... elements) {
    Integer[] array = new Integer[elements.length];
    int i = 0;
    for (Object e : elements) {
      array[i++] = (Integer) e;
    }
    return create(array);
  }

  protected abstract Set<Integer> create(Integer[] elements);

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

    return new Strings();
  }

  @Override
  public Set<String> create(Object... elements) {
    String[] array = new String[elements.length];
    int i = 0;
    for (Object e : elements) {
      array[i++] = (String) e;
    }
    return create(array);
  }

  protected abstract Set<String> create(String[] elements);

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

    this.equivalence = checkNotNull(equivalence);
  }

  /**
   * Different orderings for combining the elements of an input array, which must all produce the
   * same result.
   */
  enum CollectStrategy {
    /** Get one accumulator and accumulate the elements into it sequentially. */
    SEQUENTIAL {
      @Override

  }

  public static class Chars extends SampleElements<Character> {
    public Chars() {
      // elements aren't sorted, to better test SortedSet iteration ordering
      super('b', 'a', 'c', 'd', 'e');
    }
  }

  public static class Enums extends SampleElements<AnEnum> {
    public Enums() {
      // elements aren't sorted, to better test SortedSet iteration ordering
      super(AnEnum.B, AnEnum.A, AnEnum.C, AnEnum.D, AnEnum.E);

 */
@GwtCompatible
@ElementTypesAreNonnullByDefault
public abstract class TestIntegerSortedSetGenerator extends TestIntegerSetGenerator {
  @Override
  protected abstract SortedSet<Integer> create(Integer[] elements);

  /** Sorts the elements by their natural ordering. */
  @Override
  public List<Integer> order(List<Integer> insertionOrder) {
    sort(insertionOrder);
    return insertionOrder;
  }

  @CollectionFeature.Require(ALLOWS_NULL_VALUES)
  public void testEquals_containingNull() {
    ArrayList<E> elements = new ArrayList<>(getSampleElements());
    elements.set(elements.size() / 2, null);
    collection = getSubjectGenerator().create(elements.toArray());
    List<E> other = new ArrayList<>(getSampleElements());
    assertFalse(

        final EnumerationIterator<String> itr = new EnumerationIterator<String>(vector.elements());
        itr.remove();
    }

    /**
     * @throws Exception
     */
    @Test
    public void testNext() throws Exception {
        final EnumerationIterator<String> itr = new EnumerationIterator<String>(new Vector<String>().elements());
        assertThat(itr.hasNext(), is(not(true)));
    }

    /**

   *       href="https://github.com/google/guava/wiki/GraphsExplained#graph-elements-nodes-and-edges">
   *       graph elements</a> for details)
   * </ul>
   *
   * @throws IllegalArgumentException if {@code node} is not an element of this graph
   */
  Iterable<? extends N> successors(N node);

  /** Returns the sample elements that this generate populates its container with. */
  SampleElements<E> samples();

  /**
   * Creates a new container containing the given elements. TODO: would be nice to figure out how to
   * use E... or E[] as a parameter type, but this doesn't seem to work because Java creates an
   * array of the erased type.
   */
  T create(Object... elements);

  /**