*
   * <pre>{@code
   * a
   * }</pre>
   */
  private static final SuccessorsFunction<Character> SINGLE_ROOT = createSingleRootGraph();

  /**
   * A graph that is not a tree (for example, it has two antiparallel edge between {@code e} and
   * {@code f} and thus has a cycle) but is a valid input to {@link Traverser#forTree} when starting

   * specified by {@link Double#toString(double)}, and separated by {@code separator}. For example,
   * {@code join("-", 1.0, 2.0, 3.0)} returns the string {@code "1.0-2.0-3.0"}.
   *
   * <p>Note that {@link Double#toString(double)} formats {@code double} differently in GWT
   * sometimes. In the previous example, it returns the string {@code "1-2-3"}.
   *

      hash += Doubles.hashCode(array[i]);
    }
    return hash;
  }

  /**
   * Returns a string representation of this array in the same form as {@link
   * Arrays#toString(double[])}, for example {@code "[1, 2, 3]"}.
   */
  @Override
  public String toString() {
    if (isEmpty()) {
      return "[]";
    }
    StringBuilder builder = new StringBuilder(length() * 5); // rough estimate is fine

 * <p>Some uses of this class include
 *
 * <ul>
 *   <li>As a method return type, as an alternative to returning {@code null} to indicate that no
 *       value was available
 *   <li>To distinguish between "unknown" (for example, not present in a map) and "known to have no
 *       value" (present in the map, with value {@code Optional.absent()})
 *   <li>To wrap nullable references for storage in a collection that does not support {@code null}

    return FluentIterable.concat(inputs);
  }

  /**
   * Divides an iterable into unmodifiable sublists of the given size (the final iterable may be
   * smaller). For example, partitioning an iterable containing {@code [a, b, c, d, e]} with a
   * partition size of 3 yields {@code [[a, b, c], [d, e]]} -- an outer iterable containing two
   * inner lists of three and two elements, all in the original order.

     * requires us to define extra classes -- unfortunate under Android.) *Then* we could consider
     * lying about the fields below on the grounds that we always initialize them just after the
     * constructor -- an example of the kind of lying that our hypothetical bytecode rewriter would
     * already have to deal with, thanks to DI frameworks that perform field and method injection,

   * convenient.
   *
   * <p>By default, a {@code Builder} will generate maps that iterate over entries in the order they
   * were inserted into the builder, equivalently to {@code LinkedHashMap}. For example, in the
   * above example, {@code WORD_TO_INT.entrySet()} is guaranteed to iterate over the entries in the
   * order {@code "one"=1, "two"=2, "three"=3}, and {@code keySet()} and {@code values()} respect

 *   <li>{@link #isOrdered} / {@link #isStrictlyOrdered}
 *   <li>{@link #min} / {@link #max}
 * </ul>
 *
 * <h3>Understanding complex orderings</h3>
 *
 * <p>Complex chained orderings like the following example can be challenging to understand.
 *
 * <pre>{@code
 * Ordering<Foo> ordering =
 *     Ordering.natural()
 *         .nullsFirst()
 *         .onResultOf(getBarFunction)
 *         .nullsLast();
 * }</pre>
 *

   */
  private @Nullable Object generate(TypeToken<?> type) {
    Class<?> rawType = type.getRawType();
    List<Object> samples = sampleInstances.get(rawType);
    Object sample = pickInstance(samples, null);
    if (sample != null) {
      return sample;
    }
    if (rawType.isEnum()) {
      return pickInstance(rawType.getEnumConstants(), null);
    }
    if (type.isArray()) {

   * java.util.stream} Javadoc), that order is preserved, but entries are <a
   * href="ImmutableMultimap.html#iteration">grouped by key</a>.
   *
   * <p>Example:
   *
   * <pre>{@code
   * static final Multimap<Character, String> FIRST_LETTER_MULTIMAP =
   *     Stream.of("banana", "apple", "carrot", "asparagus", "cherry")