}

  private static <K, V> ImmutableSetMultimap<K, V> copyOf(
      Multimap<? extends K, ? extends V> multimap,
      @Nullable Comparator<? super V> valueComparator) {
    checkNotNull(multimap); // eager for GWT
    if (multimap.isEmpty() && valueComparator == null) {
      return of();
    }

    if (multimap instanceof ImmutableSetMultimap) {
      @SuppressWarnings("unchecked") // safe since multimap is not writable

 * @author Louis Wasserman
 * @since 12.0
 */
@GwtIncompatible // hasn't been tested yet
public abstract class ImmutableSortedMultiset<E> extends ImmutableMultiset<E>
    implements SortedMultiset<E> {
  // TODO(lowasser): GWT compatibility

  /**
   * Returns a {@code Collector} that accumulates the input elements into a new {@code
   * ImmutableMultiset}. Elements are sorted by the specified comparator.
   *

    assertEquals(asList(3), partitions.get(1));
  }

  @J2ktIncompatible // Arrays.asList(...).subList() doesn't implement RandomAccess in J2KT.
  @GwtIncompatible // ArrayList.subList doesn't implement RandomAccess in GWT.
  public void testPartitionRandomAccessTrue() {
    List<Integer> source = asList(1, 2, 3);
    List<List<Integer>> partitions = partition(source, 2);

    assertTrue(

    assertThrows(NullPointerException.class, () -> builder.put(immutableEntry((String) null, 1)));
    builder.put("foo", 2);
    assertMapEquals(builder.buildOrThrow(), "foo", 2);
  }

  // for GWT compatibility
  static class SimpleEntry<K, V> extends AbstractMapEntry<K, V> {
    public K key;
    public V value;

    SimpleEntry(K key, V value) {
      this.key = key;
      this.value = value;
    }

    checkArgument(!token.isEmpty());
    return Ascii.toLowerCase(token);
  }

  private static String normalizeParameterValue(String attribute, String value) {
    checkNotNull(value); // for GWT
    checkArgument(ascii().matchesAllOf(value), "parameter values must be ASCII: %s", value);
    return attribute.equals(CHARSET_ATTRIBUTE) ? Ascii.toLowerCase(value) : value;
  }

  /**

 * to prioritize memory over CPU.
 *
 * @author Louis Wasserman
 * @author Jon Noack
 */
@GwtIncompatible // not worth using in GWT for now
class CompactHashMap<K extends @Nullable Object, V extends @Nullable Object>
    extends AbstractMap<K, V> implements Serializable {
  /*

    assertEquals(ImmutableSet.of(3, 2, 1), i.next());
    assertFalse(i.hasNext());
    assertThrows(NoSuchElementException.class, () -> i.next());
  }

  @GwtIncompatible // too slow for GWT
  public void testPowerSetIteration_iteratorTester() {
    ImmutableSet<Integer> elements = ImmutableSet.of(1, 2);

    Set<Set<Integer>> expected = new LinkedHashSet<>();
    expected.add(ImmutableSet.<Integer>of());

 *
 * <p>The successor to Guava's caching API is <a
 * href="https://github.com/ben-manes/caffeine/wiki">Caffeine</a>. Its API is designed to make it a
 * nearly drop-in replacement. Note that it is not available for Android or GWT/J2CL and that it may
 * have <a href="https://github.com/ben-manes/caffeine/wiki/Guava">different (usually better)
 * behavior</a> when multiple threads attempt concurrent mutations. Its equivalent to {@code
 * CacheBuilder} is its <a

    checkArgument(!token.isEmpty());
    return Ascii.toLowerCase(token);
  }

  private static String normalizeParameterValue(String attribute, String value) {
    checkNotNull(value); // for GWT
    checkArgument(ascii().matchesAllOf(value), "parameter values must be ASCII: %s", value);
    return attribute.equals(CHARSET_ATTRIBUTE) ? Ascii.toLowerCase(value) : value;
  }

  /**

   *
   * @throws IllegalArgumentException if {@code x <= 0}
   * @since 20.0
   */
  public static long floorPowerOfTwo(long x) {
    checkPositive("x", x);

    // Long.highestOneBit was buggy on GWT.  We've fixed it, but I'm not certain when the fix will
    // be released.
    return 1L << ((Long.SIZE - 1) - Long.numberOfLeadingZeros(x));
  }

  /**
   * Returns {@code true} if {@code x} represents a power of two.