InternetDomainName domain = InternetDomainName.from("foo.city.yokohama.jp");
    assertTrue(domain.hasPublicSuffix());
    assertEquals("yokohama.jp", domain.publicSuffix().toString());

    // Behold the weirdness!
    assertFalse(domain.publicSuffix().isPublicSuffix());
  }

  public void testPublicSuffixMultipleUnders() {
    // PSL has both *.uk and *.sch.uk; the latter should win.

    InternetDomainName domain = InternetDomainName.from("foo.city.yokohama.jp");
    assertTrue(domain.hasPublicSuffix());
    assertEquals("yokohama.jp", domain.publicSuffix().toString());

    // Behold the weirdness!
    assertFalse(domain.publicSuffix().isPublicSuffix());
  }

  public void testPublicSuffixMultipleUnders() {
    // PSL has both *.uk and *.sch.uk; the latter should win.

    ImmutableMap.Builder<String, Integer> builder = new Builder<>();
    final StringHolder holder = new StringHolder();
    holder.string = "one";
    Entry<String, Integer> entry =
        new AbstractMapEntry<String, Integer>() {
          @Override
          public String getKey() {
            return holder.string;
          }

          @Override
          public Integer getValue() {

    class Holder {

      int value = 2;
    }
    final Holder holder = new Holder();

    // This function adds the holder's value to the input value.
    Function<Integer, Integer> adder =
        new Function<Integer, Integer>() {
          @Override
          public Integer apply(Integer from) {
            return from + holder.value;
          }
        };

    class Holder {

      int value = 2;
    }
    final Holder holder = new Holder();

    // This function adds the holder's value to the input value.
    Function<Integer, Integer> adder =
        new Function<Integer, Integer>() {
          @Override
          public Integer apply(Integer from) {
            return from + holder.value;
          }
        };

   * contention. See above for explanation. This method suffers the usual non-modularity problems of
   * optimistic retry code, relying on rechecked sets of reads.
   *
   * @param x the value
   * @param hc the hash code holder
   * @param wasUncontended false if CAS failed before call
   */
  final void retryUpdate(long x, @CheckForNull int[] hc, boolean wasUncontended) {
    int h;
    if (hc == null) {

   * contention. See above for explanation. This method suffers the usual non-modularity problems of
   * optimistic retry code, relying on rechecked sets of reads.
   *
   * @param x the value
   * @param hc the hash code holder
   * @param wasUncontended false if CAS failed before call
   */
  final void retryUpdate(long x, @CheckForNull int[] hc, boolean wasUncontended) {
    int h;
    if (hc == null) {

   * contention. See above for explanation. This method suffers the usual non-modularity problems of
   * optimistic retry code, relying on rechecked sets of reads.
   *
   * @param x the value
   * @param hc the hash code holder
   * @param wasUncontended false if CAS failed before call
   */
  final void retryUpdate(long x, @CheckForNull int[] hc, boolean wasUncontended) {
    int h;
    if (hc == null) {

    return (nullableReference == null) ? Optional.<T>absent() : new Present<T>(nullableReference);
  }

  Optional() {}

  /**
   * Returns {@code true} if this holder contains a (non-null) instance.
   *
   * <p><b>Comparison to {@code java.util.Optional}:</b> no differences.
   */
  public abstract boolean isPresent();

  /**

    @ParametricNullness
    public T get() {
      // Another variant of Double Checked Locking.
      //
      // We use two volatile reads. We could reduce this to one by
      // putting our fields into a holder class, but (at least on x86)
      // the extra memory consumption and indirection are more
      // expensive than the extra volatile reads.
      long nanos = expirationNanos;
      long now = System.nanoTime();