* limitations under the License.
 */

package com.google.common.collect;

import static com.google.common.base.Preconditions.checkState;
import static java.util.Collections.synchronizedSet;
import static java.util.Collections.unmodifiableSet;

import com.google.common.base.Equivalence;
import java.util.Collection;
import java.util.HashSet;
import java.util.LinkedHashSet;
import java.util.Map;

 * limitations under the License.
 */

package com.google.common.collect;

import static com.google.common.base.Preconditions.checkState;
import static java.util.Collections.synchronizedSet;
import static java.util.Collections.unmodifiableSet;

import com.google.common.base.Equivalence;
import java.util.Collection;
import java.util.HashSet;
import java.util.LinkedHashSet;
import java.util.Map;

  @VisibleForTesting
  static <E extends @Nullable Object> Set<E> set(Set<E> set, @CheckForNull Object mutex) {
    return new SynchronizedSet<>(set, mutex);
  }

  static class SynchronizedSet<E extends @Nullable Object> extends SynchronizedCollection<E>
      implements Set<E> {

    SynchronizedSet(Set<E> delegate, @CheckForNull Object mutex) {
      super(delegate, mutex);
    }

    @Override
    Set<E> delegate() {

  @VisibleForTesting
  static <E extends @Nullable Object> Set<E> set(Set<E> set, @CheckForNull Object mutex) {
    return new SynchronizedSet<>(set, mutex);
  }

  static class SynchronizedSet<E extends @Nullable Object> extends SynchronizedCollection<E>
      implements Set<E> {

    SynchronizedSet(Set<E> delegate, @CheckForNull Object mutex) {
      super(delegate, mutex);
    }

    @Override
    Set<E> delegate() {