if (existingCounter == null) {
          return 0;
        }
        // existingCounter != null: fall through to operate against the existing AtomicInteger
      }

      while (true) {
        int oldValue = existingCounter.get();
        if (oldValue != 0) {
          try {
            int newValue = IntMath.checkedAdd(oldValue, occurrences);

   * ImmutableEnumSet/ImmutableSortedSet, regardless of implementation type. It
   * captures their "logical contents" and they are reconstructed using public
   * static factories. This is necessary to ensure that the existence of a
   * particular implementation type is an implementation detail.
   */
  @J2ktIncompatible // serialization
  private static class SerializedForm implements Serializable {
    final Object[] elements;

 * common ways to create a {@code ListenableFuture} include instantiating a {@link SettableFuture},
 * submitting a task to a {@link ListeningExecutorService}, and deriving a {@code Future} from an
 * existing one, typically using methods like {@link Futures#transform(ListenableFuture,
 * com.google.common.base.Function, java.util.concurrent.Executor) Futures.transform} and {@link

    EnumHashBiMap<Currency, Country> bimap2 = EnumHashBiMap.create(emptyBimap2);
    assertTrue(bimap2.isEmpty());
  }

  public void testEnumHashBiMapConstructor() {
    /* Test that it copies existing entries. */
    EnumHashBiMap<Currency, String> bimap1 = EnumHashBiMap.create(Currency.class);
    bimap1.put(Currency.DOLLAR, "dollar");
    EnumHashBiMap<Currency, String> bimap2 = EnumHashBiMap.create(bimap1);

   *     expectContents(E...)} and its friends.
   */
  protected abstract Collection<E> actualContents();

  /**
   * Replaces the existing container under test with a new container created by the subject
   * generator.
   *
   * @see #resetContainer(Object) resetContainer(C)
   * @return the new container instance.
   */
  @CanIgnoreReturnValue

   *
   * <p>If {@code range} {@linkplain Range#isEmpty() is empty}, then this is a no-op.
   */
  void put(Range<K> range, V value);

  /**
   * Maps a range to a specified value, coalescing this range with any existing ranges with the same
   * value that are {@linkplain Range#isConnected connected} to this range.
   *
   * <p>The behavior of {@link #get(Comparable) get(k)} after calling this method is identical to

    bimap = EnumBiMap.create(emptyBimap);
    assertTrue(bimap.isEmpty());
  }

  public void testEnumBiMapConstructor() {
    /* Test that it copies existing entries. */
    EnumBiMap<Currency, Country> bimap1 = EnumBiMap.create(Currency.class, Country.class);
    bimap1.put(Currency.DOLLAR, Country.CANADA);
    EnumBiMap<Currency, Country> bimap2 = EnumBiMap.create(bimap1);

    bimap = EnumBiMap.create(emptyBimap);
    assertTrue(bimap.isEmpty());
  }

  public void testEnumBiMapConstructor() {
    /* Test that it copies existing entries. */
    EnumBiMap<Currency, Country> bimap1 = EnumBiMap.create(Currency.class, Country.class);
    bimap1.put(Currency.DOLLAR, Country.CANADA);
    EnumBiMap<Currency, Country> bimap2 = EnumBiMap.create(bimap1);

 * together. Any creation method that would customarily respect insertion order (such as {@link
 * #copyOf(Multimap)}) instead preserves key-grouped order by inserting entries for an existing key
 * immediately after the last entry having that key.
 *
 * <p>See the Guava User Guide article on <a href=
 * "https://github.com/google/guava/wiki/ImmutableCollectionsExplained">immutable collections</a>.
 *

 * together. Any creation method that would customarily respect insertion order (such as {@link
 * #copyOf(Multimap)}) instead preserves key-grouped order by inserting entries for an existing key
 * immediately after the last entry having that key.
 *
 * <p>See the Guava User Guide article on <a href=
 * "https://github.com/google/guava/wiki/ImmutableCollectionsExplained">immutable collections</a>.
 *