ImmutableSortedMap::copyOfSorted);
  }

  // unsafe, comparator() returns a comparator on the specified type
  @SuppressWarnings("unchecked")
  public static <K, V> ImmutableSortedMap<K, V> of() {
    return new Builder<K, V>((Comparator<K>) NATURAL_ORDER).build();
  }

  public static <K extends Comparable<? super K>, V> ImmutableSortedMap<K, V> of(K k1, V v1) {

    Collector<Entry<String, Integer>, ?, ImmutableSortedMap<String, Integer>> collector =
        ImmutableSortedMap.toImmutableSortedMap(
            String.CASE_INSENSITIVE_ORDER, Entry::getKey, Entry::getValue);
    BiPredicate<ImmutableSortedMap<String, Integer>, ImmutableSortedMap<String, Integer>>
        equivalence =
            Equivalence.equals()
                .onResultOf(ImmutableSortedMap<String, Integer>::comparator)

  public void testToImmutableSortedMap_java7_combine() {
    ImmutableSortedMap.Builder<String, Integer> zis =
        ImmutableSortedMap.<String, Integer>naturalOrder().put("one", 1).put("four", 4);
    ImmutableSortedMap.Builder<String, Integer> zat =
        ImmutableSortedMap.<String, Integer>naturalOrder().put("two", 2).put("three", 3);
    ImmutableSortedMap<String, Integer> sortedMap = zis.combine(zat).build();

     */
    return Collector.of(
        () -> new ImmutableSortedMap.Builder<K, V>(comparator),
        (builder, input) -> builder.put(keyFunction.apply(input), valueFunction.apply(input)),
        ImmutableSortedMap.Builder::combine,
        ImmutableSortedMap.Builder::buildOrThrow,
        Collector.Characteristics.UNORDERED);
  }

     */
    return Collector.of(
        () -> new ImmutableSortedMap.Builder<K, V>(comparator),
        (builder, input) -> builder.put(keyFunction.apply(input), valueFunction.apply(input)),
        ImmutableSortedMap.Builder::combine,
        ImmutableSortedMap.Builder::buildOrThrow,
        Collector.Characteristics.UNORDERED);
  }

    assertEquals(ImmutableMap.of(), ArbitraryInstances.get(ImmutableMap.class));
    assertEquals(ImmutableSortedMap.of(), ArbitraryInstances.get(SortedMap.class));
    assertEquals(ImmutableSortedMap.of(), ArbitraryInstances.get(ImmutableSortedMap.class));
    assertEquals(ImmutableMultiset.of(), ArbitraryInstances.get(Multiset.class));

          .put(Map.class, ImmutableMap.of())
          .put(ImmutableMap.class, ImmutableMap.of())
          .put(SortedMap.class, ImmutableSortedMap.of())
          .put(ImmutableSortedMap.class, ImmutableSortedMap.of())
          .put(NavigableMap.class, Maps.unmodifiableNavigableMap(Maps.newTreeMap()))
          .put(Multimap.class, ImmutableMultimap.of())

          .put(Map.class, ImmutableMap.of())
          .put(ImmutableMap.class, ImmutableMap.of())
          .put(SortedMap.class, ImmutableSortedMap.of())
          .put(ImmutableSortedMap.class, ImmutableSortedMap.of())
          .put(NavigableMap.class, Maps.unmodifiableNavigableMap(Maps.newTreeMap()))
          .put(Multimap.class, ImmutableMultimap.of())

    assertEquals(ImmutableMap.of(), ArbitraryInstances.get(ImmutableMap.class));
    assertEquals(ImmutableSortedMap.of(), ArbitraryInstances.get(SortedMap.class));
    assertEquals(ImmutableSortedMap.of(), ArbitraryInstances.get(ImmutableSortedMap.class));
    assertEquals(ImmutableMultiset.of(), ArbitraryInstances.get(Multiset.class));

import com.google.common.collect.ImmutableMultiset;
import com.google.common.collect.ImmutableSet;
import com.google.common.collect.ImmutableSetMultimap;
import com.google.common.collect.ImmutableSortedMap;
import com.google.common.collect.ImmutableSortedMultiset;
import com.google.common.collect.ImmutableSortedSet;
import com.google.common.collect.ImmutableTable;
import com.google.common.collect.LinkedHashMultimap;