* Iterables#filter(Iterable, Class)} for related functionality.)
   *
   * <p><b>{@code Stream} equivalent:</b> {@link java.util.stream.Stream#filter Stream.filter}.
   */
  // TODO(kevinb): how can we omit that Iterables link when building gwt
  // javadoc?
  public static <E extends @Nullable Object> Collection<E> filter(
      Collection<E> unfiltered, Predicate<? super E> predicate) {

   * 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.

  /**

   * @throws IndexOutOfBoundsException if {@code off} is negative, if {@code len} is negative, or if
   *     {@code off + len} is greater than {@code b.length}
   */
  @CanIgnoreReturnValue
  // Sometimes you don't care how many bytes you actually read, I guess.
  // (You know that it's either going to read len bytes or stop at EOF.)
  public static int read(InputStream in, byte[] b, int off, int len) throws IOException {
    checkNotNull(in);

    if (array.length <= 1) {
      return;
    }

    int length = toIndex - fromIndex;
    // Obtain m = (-distance mod length), a non-negative value less than "length". This is how many
    // places left to rotate.
    int m = -distance % length;
    m = (m < 0) ? m + length : m;
    // The current index of what will become the first element of the rotated section.

   * <p>Calling {@code setDistinctValues(type, v1, v2)} also sets the default value for {@code type}
   * that's used for {@link #testNulls}.
   *
   * <p>Only necessary for types where {@link ClassSanityTester} doesn't already know how to create
   * distinct values.
   *
   * @return this tester instance
   * @since 17.0
   */
  @CanIgnoreReturnValue
  public <T> ClassSanityTester setDistinctValues(Class<T> type, T value1, T value2) {

   * java.util.stream.Stream#filter}. This method is not being deprecated, but we gently encourage
   * you to migrate to streams.
   */
  // TODO(kevinb): how to omit that last sentence when building GWT javadoc?
  public static <E extends @Nullable Object> Set<E> filter(
      Set<E> unfiltered, Predicate<? super E> predicate) {
    if (unfiltered instanceof SortedSet) {

    FilenameFilter filter = new PatternFilenameFilter("a+");
    assertTrue(filter.accept(dir, "a"));
    assertTrue(filter.accept(dir, "aaaa"));
    assertFalse(filter.accept(dir, "b"));

    // Show that dir is ignored
    assertTrue(filter.accept(null, "a"));
  }

  public void testNulls() throws Exception {
    NullPointerTester tester = new NullPointerTester();

 *   }
 * }, executor);
 * }</pre>
 *
 * <h3>How to get an instance</h3>
 *
 * <p>We encourage you to return {@code ListenableFuture} from your methods so that your users can
 * take advantage of the {@linkplain Futures utilities built atop the class}. The way that you will
 * create {@code ListenableFuture} instances depends on how you currently create {@code Future}
 * instances:
 *
 * <ul>

   * this is translated to throttling time is discussed later). Immediately after, assume that an
   * acquire(10) request arriving. We serve the request partly from storedPermits, using all the
   * remaining 7.0 permits, and the remaining 3.0, we serve them by fresh permits produced by the
   * rate limiter.
   *
   * We already know how much time it takes to serve 3 fresh permits: if the rate is

 *       token attempt, one measure of the quality of a hash function is <i>how well</i> it succeeds
 *       at this goal. Important note: it may be easy to achieve the theoretical minimum collision
 *       rate when using completely <i>random</i> sample input. The true test of a hash function is
 *       how it performs on representative real-world data, which tends to contain many hidden