*
   * <p>Results are undefined if {@code set1} and {@code set2} are sets based on different
   * equivalence relations, for example if {@code set1} is a {@link HashSet} and {@code set2} is a
   * {@link TreeSet} or the {@link Map#keySet} of an {@code IdentityHashMap}.
   */
  public static <E extends @Nullable Object> SetView<E> difference(Set<E> set1, Set<?> set2) {
    checkNotNull(set1, "set1");
    checkNotNull(set2, "set2");

	for {
		select {
		case <-ctx.Done():
			return
		case <-timer.C:
			var wg sync.WaitGroup
			for _, set := range s.sets {
				wg.Add(1)
				go func(set *erasureObjects) {
					defer wg.Done()
					if set == nil {
						return
					}
					set.cleanupDeletedObjects(ctx)
				}(set)
			}
			wg.Wait()

			// Reset for the next interval
			timer.Reset(globalAPIConfig.getDeleteCleanupInterval())

    assertTrue(set.containsAll(Sets.newTreeSet(asList("a", "b", "f"))));
    assertFalse(set.containsAll(Sets.newTreeSet(asList("d"))));
    assertFalse(set.containsAll(Sets.newTreeSet(asList("z"))));
    assertFalse(set.containsAll(Sets.newTreeSet(asList("b", "d"))));
    assertFalse(set.containsAll(Sets.newTreeSet(asList("f", "d", "a"))));
  }

	tmpFormat.Erasure.This = ""
	if len(reference.Erasure.Sets) != len(format.Erasure.Sets) {
		return fmt.Errorf("Expected number of sets %d, got %d", len(reference.Erasure.Sets), len(format.Erasure.Sets))
	}

	// Make sure that the sets match.
	for i := range reference.Erasure.Sets {
		if len(reference.Erasure.Sets[i]) != len(format.Erasure.Sets[i]) {
			return fmt.Errorf("Each set should be of same size, expected %d got %d",

	}
	if len(formatV3.Erasure.Sets) != 1 {
		t.Fatalf("expected single set after migrating from v1 to v3, but found %d", len(formatV3.Erasure.Sets))
	}
	if !reflect.DeepEqual(formatV3.Erasure.Sets[0], m.Erasure.JBOD) {
		t.Fatalf("expected drive uuid: %v, got: %v", m.Erasure.JBOD, formatV3.Erasure.Sets[0])
	}

	m = &formatErasureV1{}
	m.Format = "unknown"

     */
    String getMethod();

    /**
     * Sets the HTTP method for the URL queue.
     *
     * @param method the HTTP method to be set (e.g., GET, POST, etc.)
     */
    void setMethod(String method);

    /**
     * Retrieves the URL from the queue.
     *
     * @return the URL as a String.
     */
    String getUrl();

    /**
     * Sets the URL for this UrlQueue.
     *

    }

    /**
     * Gets the character set of the response.
     *
     * @return the character set, or null if not specified
     */
    public String getCharSet() {
        return charSet;
    }

    /**
     * Sets the character set of the response.
     *
     * @param charSet the character set to set
     */
    public void setCharSet(final String charSet) {

  private Iterable<List<Object>> buildCartesianProduct(Set<?>... sets) {
    List<Set<Optional<?>>> optionalSets = Lists.newArrayListWithExpectedSize(sets.length);
    for (Set<?> set : sets) {
      Set<Optional<?>> optionalSet =
          Sets.newLinkedHashSet(Iterables.transform(set, NULLABLE_TO_OPTIONAL));
      optionalSets.add(optionalSet);
    }
    Set<List<Optional<?>>> cartesianProduct = Sets.cartesianProduct(optionalSets);

     */
    IDTYPE getId();

    /**
     * Sets the identifier of the access result.
     *
     * @param id the identifier
     */
    void setId(IDTYPE id);

    /**
     * Returns the session identifier.
     *
     * @return the session identifier
     */
    String getSessionId();

    /**
     * Sets the session identifier.
     *
     * @param sessionId the session identifier

- *If total drives has many common divisors the algorithm chooses the minimum amounts of erasure sets possible for a erasure set size of any N*.  In the example with 1024 drives - 4, 8, 16 are GCD factors. With 16 drives we get a total of 64 possible sets, with 8 drives we get a total of 128 possible sets, with 4 drives we get a total of 256 possible sets. So algorithm automatically chooses 64 sets, which is *16* 64 = 1024* drives in total.