SortedSet<@Nullable String> keySet = multimap.keySet();

    assertEquals(null, keySet.first());
    assertEquals("google", keySet.last());
    assertEquals(StringLength.COMPARATOR, keySet.comparator());
    assertEquals(Sets.<@Nullable String>newHashSet(null, "tree"), keySet.headSet("yahoo"));
    assertEquals(Sets.newHashSet("google"), keySet.tailSet("yahoo"));
    assertEquals(Sets.newHashSet("tree"), keySet.subSet("ask", "yahoo"));
  }

    assertEquals("", joiner.join(set));
    assertEquals("", joiner.join(set.iterator()));

    Object[] array = Lists.newArrayList(set).toArray(new Integer[0]);
    assertEquals("", joiner.join(array));

    StringBuilder sb1FromIterable = new StringBuilder();
    assertSame(sb1FromIterable, joiner.appendTo(sb1FromIterable, set));
    assertEquals(0, sb1FromIterable.length());

    assertNull(Optional.toJavaUtil(null));
    assertEquals(java.util.Optional.empty(), Optional.toJavaUtil(Optional.absent()));
    assertEquals(java.util.Optional.of("abc"), Optional.toJavaUtil(Optional.of("abc")));
  }

  public void testToJavaUtil_instance() {
    assertEquals(java.util.Optional.empty(), Optional.absent().toJavaUtil());
    assertEquals(java.util.Optional.of("abc"), Optional.of("abc").toJavaUtil());
  }

    assertEquals(ImmutableSet.of(1), testTable.columnKeySet());
  }

  public void testColumnMap() {
    assertEquals(ImmutableMap.of(1, ImmutableMap.of('a', "blah")), testTable.columnMap());
  }

  public void testRow() {
    assertEquals(ImmutableMap.of(), testTable.row('A'));
    assertEquals(ImmutableMap.of(1, "blah"), testTable.row('a'));
  }

  public void testRowKeySet() {

    assertEquals(Collections.emptyList(), multimap.get("foo"));
    assertEquals(0, multimap.hashCode());
    assertTrue(multimap.isEmpty());
    assertEquals(HashMultiset.create(), multimap.keys());
    assertEquals(Collections.emptySet(), multimap.keySet());
    assertEquals(0, multimap.size());
    assertTrue(multimap.values().isEmpty());
    assertEquals("{}", multimap.toString());
  }

    assertEquals(Collections.emptySet(), multimap.get("foo"));
    assertEquals(0, multimap.hashCode());
    assertTrue(multimap.isEmpty());
    assertEquals(HashMultiset.create(), multimap.keys());
    assertEquals(Collections.emptySet(), multimap.keySet());
    assertEquals(0, multimap.size());
    assertTrue(multimap.values().isEmpty());
    assertEquals("{}", multimap.toString());
  }

    assertEquals(expected, helper.toString());
    // Call toString again
    assertEquals(expected, helper.toString());

    // Make sure the cached value is reset when we modify the helper at all
    final String expected2 = "TestClass{field1=1, value1, field2=value2, 2}";
    helper.addValue(2);
    assertEquals(expected2, helper.toString());
  }

    Set<K> keySet = map.keySet();
    Collection<V> valueCollection = map.values();
    Set<Entry<K, V>> entrySet = map.entrySet();

    assertEquals(map.size() == 0, map.isEmpty());
    assertEquals(map.size(), keySet.size());
    assertEquals(keySet.size() == 0, keySet.isEmpty());
    assertEquals(!keySet.isEmpty(), keySet.iterator().hasNext());

    int expectedKeySetHash = 0;
    for (K key : keySet) {
      V value = map.get(key);

    ImmutableList<String> list = multiset.asList();
    assertEquals(ImmutableList.of("a", "a", "b", "b", "b"), list);
    SerializableTester.reserializeAndAssert(list);
    assertEquals(2, list.indexOf("b"));
    assertEquals(4, list.lastIndexOf("b"));
  }

  private static class IntegerDiv10 implements Comparable<IntegerDiv10> {
    final int value;

    assertEquals(ImmutableSet.of(), i.next());
    assertEquals(ImmutableSet.of(1), i.next());
    assertEquals(ImmutableSet.of(2), i.next());
    assertEquals(ImmutableSet.of(2, 1), i.next());
    assertEquals(ImmutableSet.of(3), i.next());
    assertEquals(ImmutableSet.of(3, 1), i.next());
    assertEquals(ImmutableSet.of(3, 2), i.next());
    assertEquals(ImmutableSet.of(3, 2, 1), i.next());