@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) {
    Collections.sort(insertionOrder);
    return insertionOrder;
  }

@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) {
    Collections.sort(insertionOrder);
    return insertionOrder;
  }