}

  boolean usesKeyReferences() {
    return keyStrength != Strength.STRONG;
  }

  boolean usesValueReferences() {
    return valueStrength != Strength.STRONG;
  }

  enum Strength {
    /*
     * TODO(kevinb): If we strongly reference the value and aren't loading, we needn't wrap the
     * value. This could save ~8 bytes per entry.
     */

    STRONG {
      @Override

   *
   * <p>The iteration order of the returned map follows the enum's iteration order, not the order in
   * which the elements appear in the given map.
   *
   * @param map the map to make an immutable copy of
   * @return an immutable map containing those entries
   * @since 14.0
   */
  @GwtCompatible(serializable = true)
  public static <K extends Enum<K>, V> ImmutableMap<K, V> immutableEnumMap(
      Map<K, ? extends V> map) {

  }

  boolean usesKeyReferences() {
    return keyStrength != Strength.STRONG;
  }

  boolean usesValueReferences() {
    return valueStrength != Strength.STRONG;
  }

  enum Strength {
    /*
     * TODO(kevinb): If we strongly reference the value and aren't loading, we needn't wrap the
     * value. This could save ~8 bytes per entry.
     */

    STRONG {
      @Override

   */
  @VisibleForTesting
  CountDownLatch whenClosedCountDown() {
    return closeables.whenClosedCountDown();
  }

  /** The state of a {@link CloseableList}. */
  enum State {
    /** The {@link CloseableList} has not been subsumed or closed. */
    OPEN,

    /**
     * The {@link CloseableList} has been subsumed into another. It may not be closed or subsumed