/** A collection of elements to retain, along with a description for use in failure messages. */
  private class Target {
    private final Collection<E> toRetain;
    private final String description;

    private Target(Collection<E> toRetain, String description) {
      this.toRetain = toRetain;
      this.description = description;
    }

    @Override
    public String toString() {

  private final char[] table;
  private final boolean containsZero;
  private final long filter;

  private SmallCharMatcher(char[] table, long filter, boolean containsZero, String description) {
    super(description);
    this.table = table;
    this.filter = filter;
    this.containsZero = containsZero;
  }

  private static final int C1 = 0xcc9e2d51;
  private static final int C2 = 0x1b873593;

  /*

  /** A collection of elements to retain, along with a description for use in failure messages. */
  private class Target {
    private final Collection<E> toRetain;
    private final String description;

    private Target(Collection<E> toRetain, String description) {
      this.toRetain = toRetain;
      this.description = description;
    }

    @Override
    public String toString() {

      int negatedCharacters = DISTINCT_CHARS - totalCharacters;
      String suffix = ".negate()";
      final String description = toString();
      String negatedDescription =
          description.endsWith(suffix)
              ? description.substring(0, description.length() - suffix.length())
              : description + suffix;
      return new NegatedFastMatcher(
          precomputedPositive(negatedCharacters, table, negatedDescription)) {

  private Enums() {}

  /**
   * Returns the {@link Field} in which {@code enumValue} is defined. For example, to get the {@code
   * Description} annotation on the {@code GOLF} constant of enum {@code Sport}, use {@code
   * Enums.getField(Sport.GOLF).getAnnotation(Description.class)}.
   *
   * @since 12.0
   */
  @GwtIncompatible // reflection
  public static Field getField(Enum<?> enumValue) {
    Class<?>

  /**
   * Removes a single key-value pair with the key {@code key} and the value {@code value} from this
   * multimap, if such exists. If multiple key-value pairs in the multimap fit this description,
   * which one is removed is unspecified.
   *
   * @return {@code true} if the multimap changed
   */
  @CanIgnoreReturnValue
  boolean remove(
      @CompatibleWith("K") @CheckForNull Object key,

   * implementation. Experimentally determined.
   */
  private static final int MAX_HASH_BUCKET_LENGTH = 9;

  // See CompactHashMap for a detailed description of how the following fields work. That
  // description talks about `keys`, `values`, and `entries`; here the `keys` and `values` arrays
  // are replaced by a single `elements` array but everything else works similarly.

  /**

   * Often called multiple times (that is, both when the inputs complete and when the output
   * completes).
   *
   * <p>This is similar to our proposed {@code afterCommit} method but not quite the same. See the
   * description of CL 265462958.
   */
  // TODO(user): Write more tests for memory retention.
  @ForOverride
  @OverridingMethodsMustInvokeSuper
  void releaseResources(ReleaseResourcesReason reason) {
    checkNotNull(reason);

    List<?> exp = copyToList(expected);
    List<?> act = copyToList(actual);
    String actString = act.toString();

    // Of course we could take pains to give the complete description of the
    // problem on any failure.

    // Yeah it's n^2.
    for (Object object : exp) {
      if (!act.remove(object)) {
        Assert.fail(
            "did not contain expected element "

      int negatedCharacters = DISTINCT_CHARS - totalCharacters;
      String suffix = ".negate()";
      final String description = toString();
      String negatedDescription =
          description.endsWith(suffix)
              ? description.substring(0, description.length() - suffix.length())
              : description + suffix;
      return new NegatedFastMatcher(
          precomputedPositive(negatedCharacters, table, negatedDescription)) {