* or implied. See the License for the specific language governing permissions and limitations under
 * the License.
 */

package com.google.common.util.concurrent;

import static com.google.common.collect.Sets.newConcurrentHashSet;
import static java.util.Objects.requireNonNull;
import static java.util.concurrent.atomic.AtomicIntegerFieldUpdater.newUpdater;
import static java.util.concurrent.atomic.AtomicReferenceFieldUpdater.newUpdater;

    return Sets.newHashSetWithExpectedSize(expectedSize);
  }

  static <E extends @Nullable Object> Set<E> newConcurrentHashSet() {
    // GWT's ConcurrentHashMap is a wrapper around HashMap, but it rejects null keys, which matches
    // the behaviour of the non-GWT implementation of newConcurrentHashSet().
    // On the other hand HashSet might be better for code size if apps aren't

    return Sets.newHashSetWithExpectedSize(expectedSize);
  }

  /** Returns the platform preferred implementation of a thread-safe hash set. */
  static <E> Set<E> newConcurrentHashSet() {
    return ConcurrentHashMap.newKeySet();
  }

  /**
   * Returns the platform preferred implementation of an insertion ordered set based on a hash
   * table.
   */

                  @Override
                  protected Set<String> create(String[] elements) {
                    return Sets.newConcurrentHashSet(asList(elements));
                  }
                })
            .named("Sets.newConcurrentHashSet")
            .withFeatures(CollectionSize.ANY, SetFeature.GENERAL_PURPOSE)
            .createTestSuite());

    suite.addTest(

   * @throws NullPointerException if {@code elements} or any of its contents is null
   * @since 15.0
   */
  public static <E> Set<E> newConcurrentHashSet(Iterable<? extends E> elements) {
    Set<E> set = newConcurrentHashSet();
    Iterables.addAll(set, elements);
    return set;
  }

  // LinkedHashSet

  /**
   * Creates a <i>mutable</i>, empty {@code LinkedHashSet} instance.

  }

  private static final class RecordingListener extends ServiceManager.Listener {
    volatile boolean healthyCalled;
    volatile boolean stoppedCalled;
    final Set<Service> failedServices = Sets.newConcurrentHashSet();

    @Override
    public void healthy() {
      healthyCalled = true;
    }

    @Override
    public void stopped() {
      stoppedCalled = true;
    }

    @Override