};

  static final Supplier<TreeSet<String>> STRING_TREESET_FACTORY =
      new Supplier<TreeSet<String>>() {
        @Override
        public TreeSet<String> get() {
          return new TreeSet<>(Ordering.natural().nullsLast());
        }
      };

  static void populateMultimapForGet(Multimap<Integer, String> multimap, String[] elements) {
    multimap.put(2, "foo");
    for (String element : elements) {

          // but it would help with some of these lock ordering issues.
          scheduleFailure = e;
          toReturn = new FutureAsCancellable(immediateCancelledFuture());
        } finally {
          lock.unlock();
        }
        // Call notifyFailed outside the lock to avoid lock ordering issues.
        if (scheduleFailure != null) {
          service.notifyFailed(scheduleFailure);

  public boolean containsKey(@Nullable Object key) {
    // does not impact recency ordering
    if (key == null) {
      return false;
    }
    int hash = hash(key);
    return segmentFor(hash).containsKey(key, hash);
  }

  @Override
  public boolean containsValue(@Nullable Object value) {
    // does not impact recency ordering
    if (value == null) {
      return false;
    }

   */
  private static final class ThreadConfinedTaskQueue {
    /**
     * This field is only used for identity comparisons with the current thread. Field assignments
     * are atomic, but do not provide happens-before ordering; however:
     *
     * <ul>
     *   <li>If this field's value == currentThread, we know that it's up to date, because write
     *       operations in a thread always happen-before subsequent read operations in the same

 *   <li><b>Deterministic iteration.</b> The iteration order is always well-defined, depending on
 *       how the collection was created. Typically this is insertion order unless an explicit
 *       ordering is otherwise specified (e.g. {@link ImmutableSortedSet#naturalOrder}). See the
 *       appropriate factory method for details. View collections such as {@link

import com.google.common.collect.HashMultiset;
import com.google.common.collect.ImmutableMultimap;
import com.google.common.collect.Iterables;
import com.google.common.collect.Multiset;
import com.google.common.collect.Ordering;
import com.google.common.primitives.Chars;
import org.jspecify.annotations.NullUnmarked;
import org.junit.Test;
import org.junit.runner.RunWith;
import org.junit.runners.JUnit4;

@RunWith(JUnit4.class)

  /**
   * Returns a comparator that compares two {@code char} arrays <a
   * href="http://en.wikipedia.org/wiki/Lexicographical_order">lexicographically</a>; not advisable
   * for sorting user-visible strings as the ordering may not match the conventions of the user's
   * locale. That is, it compares, using {@link #compare(char, char)}), the first pair of values

     *
     * @param <E> the element type of {@link PriorityBlockingQueue}
     * @param initialCapacity the initial capacity of the priority queue
     * @param comparator the comparator for ordering the elements in the priority queue
     * @return a new instance of {@link PriorityBlockingQueue}
     * @see PriorityBlockingQueue#PriorityBlockingQueue(int, Comparator)
     */

        Collections.addAll(multiset, elements);
        return multiset;
      }

      @Override
      public List<String> order(List<String> insertionOrder) {
        return Ordering.natural().sortedCopy(insertionOrder);
      }
    };
  }

  private static final String KEY = "puppies";

  ConcurrentMap<String, AtomicInteger> backingMap;
  ConcurrentHashMultiset<String> multiset;

   * iterables are equivalent to one another.
   *
   * <p>Note that this method performs a similar function for equivalences as {@link
   * com.google.common.collect.Ordering#lexicographical} does for orderings.
   *
   * <p>The returned object is serializable if this object is serializable.
   *
   * @since 10.0
   */
  public final <S extends @Nullable T> Equivalence<Iterable<S>> pairwise() {