}
    },

    /**
     * Disables cycle detection. This option causes the factory to return unmodified lock
     * implementations provided by the JDK, and is provided to allow applications to easily
     * parameterize when cycle detection is enabled.
     *
     * <p>Note that locks created by a factory with this policy will not participate the
     * cycle detection performed by locks created by other factories.
     */

      int[] allRequired, int requiredFrom, int requiredTo, double[] array, int from, int to) {
    // Choose the first selection to do...
    int requiredChosen = chooseNextSelection(allRequired, requiredFrom, requiredTo, from, to);
    int required = allRequired[requiredChosen];

    // ...do the first selection...
    selectInPlace(required, array, from, to);

    // ...then recursively perform the selections in the range below...

  }

  public void testSetIndirectSelf_toString() {
    final SettableFuture<Object> orig = SettableFuture.create();
    // unlike the above this indirection defeats the trivial cycle detection and causes a SOE
    orig.setFuture(
        new ForwardingListenableFuture<Object>() {
          @Override
          protected ListenableFuture<Object> delegate() {
            return orig;
          }

    assertSame(firstException.getCause(), expected.getCause());
    // lockA should work after lockB is released.
    lockB.unlock();
    lockA.lock();
  }

  // Tests transitive deadlock detection.
  public void testDeadlock_threeLocks() {
    // Establish an ordering from lockA -> lockB.
    lockA.lock();
    lockB.lock();
    lockB.unlock();
    lockA.unlock();

   * given object is also a multiset and contains equal elements with equal counts, regardless of
   * order.
   */
  @Override
  // TODO(kevinb): caveats about equivalence-relation?
  boolean equals(@CheckForNull Object object);

  /**
   * Returns the hash code for this multiset. This is defined as the sum of
   *
   * <pre>{@code

   *     <i>descending order</i>
   * @throws IllegalArgumentException if {@code k} is negative
   * @since 8.0
   */
  public <E extends T> List<E> greatestOf(Iterable<E> iterable, int k) {
    // TODO(kevinb): see if delegation is hurting performance noticeably
    // TODO(kevinb): if we change this implementation, add full unit tests.
    return this.<E>reverse().leastOf(iterable, k);
  }

  /**

 * a traditional {@code HashMap} implementation which stores keys and count values as map entries,
 * {@code ObjectCountHashMap} minimizes object allocation and reduces memory footprint.
 *
 * <p>In the absence of element deletions, this will iterate over elements in insertion order.
 */
@GwtCompatible(serializable = true, emulated = true)
@ElementTypesAreNonnullByDefault
class ObjectCountHashMap<K extends @Nullable Object> {

      if (count == 0 && !isLinkedHash) {
        contents = new ObjectCountLinkedHashMap<E>(contents);
        isLinkedHash = true;
        // to preserve insertion order through deletions, we have to switch to an actual linked
        // implementation at least for now, but this should be a super rare case
      } else if (buildInvoked) {
        contents = new ObjectCountHashMap<E>(contents);

  }

  public void testSetIndirectSelf_toString() {
    final SettableFuture<Object> orig = SettableFuture.create();
    // unlike the above this indirection defeats the trivial cycle detection and causes a SOE
    orig.setFuture(
        new ForwardingListenableFuture<Object>() {
          @Override
          protected ListenableFuture<Object> delegate() {
            return orig;
          }

  /** Constructor for use by subclasses. */
  protected Equivalence() {}

  /**
   * Returns {@code true} if the given objects are considered equivalent.
   *
   * <p>This method describes an <i>equivalence relation</i> on object references, meaning that for
   * all references {@code x}, {@code y}, and {@code z} (any of which may be null):
   *
   * <ul>
   *   <li>{@code equivalent(x, x)} is true (<i>reflexive</i> property)