assertTrue(map.remove(one, three));
    assertFalse(map.containsKey(one));
    assertFalse(map.containsValue(one));
    assertNull(map.putIfAbsent(two, three));
    assertSame(three, map.remove(two));
    assertNull(map.put(three, one));
    assertNull(map.put(one, two));

    assertThat(map).containsEntry(three, one);
    assertThat(map).containsEntry(one, two);

    assertEquals(0, segment.count);
    assertNull(segment.get(key, hash));

    // cleared
    segment.setTableEntryForTesting(index, entry);
    segment.count++;
    assertEquals(1, segment.count);
    assertSame(oldValue, segment.get(key, hash));
    oldValueRef.clear();
    assertNull(segment.remove(key, hash));
    assertEquals(0, segment.count);
    assertNull(segment.get(key, hash));
  }

    assertEquals(0, segment.count);
    assertNull(segment.get(key, hash));

    // cleared
    segment.setTableEntryForTesting(index, entry);
    segment.count++;
    assertEquals(1, segment.count);
    assertSame(oldValue, segment.get(key, hash));
    oldValueRef.clear();
    assertNull(segment.remove(key, hash));
    assertEquals(0, segment.count);
    assertNull(segment.get(key, hash));
  }

    for (BoundType type : BoundType.values()) {
      assertNull(sortedMultiset.headMultiset(e0(), type).lastEntry());
      assertNull(sortedMultiset.tailMultiset(e0(), type).firstEntry());
    }
  }

  @CollectionSize.Require(ZERO)
  public void testEmptyMultisetLast() {
    assertNull(sortedMultiset.lastEntry());
    assertThrows(
        NoSuchElementException.class, () -> assertNull(sortedMultiset.elementSet().last()));
  }

/**
 * @author higa
 *
 */
public class BigIntegerConversionUtilTest extends TestCase {

    /**
     * @throws Exception
     */
    public void testToBigIntegerForEmptyString() throws Exception {
        assertNull(BigIntegerConversionUtil.toBigInteger(""));
    }

    assertFalse(testTable.containsValue(""));
  }

  public void testGet() {
    assertEquals("blah", testTable.get('a', 1));
    assertNull(testTable.get('a', 2));
    assertNull(testTable.get('A', 1));
    assertNull(testTable.get('A', 2));
  }

  public void testIsEmpty() {
    assertFalse(testTable.isEmpty());
  }

  public void testSize() {

    assertEquals(TestEnum.CHEETO, converter.convert("CHEETO"));
    assertEquals(TestEnum.HONDA, converter.convert("HONDA"));
    assertEquals(TestEnum.POODLE, converter.convert("POODLE"));
    assertNull(converter.convert(null));
    assertNull(converter.reverse().convert(null));
  }

  @GwtIncompatible // stringConverter
  public void testStringConverter_convertError() {

    assertEquals("get(present) should return the associated value", v0(), get(k0()));
  }

  public void testGet_no() {
    assertNull("get(notPresent) should return null", get(k3()));
  }

  @MapFeature.Require(ALLOWS_NULL_KEY_QUERIES)
  public void testGet_nullNotContainedButAllowed() {
    assertNull("get(null) should return null", get(null));
  }

  @MapFeature.Require(absent = ALLOWS_NULL_KEY_QUERIES)

    Object one = new Object();
    Object two = new Object();

    assertNull(cache.getIfPresent(one));
    stats = cache.stats();
    assertEquals(1, stats.missCount());
    assertEquals(0, stats.loadSuccessCount());
    assertEquals(0, stats.loadExceptionCount());
    assertEquals(0, stats.hitCount());
    assertNull(cache.asMap().get(one));
    assertFalse(cache.asMap().containsKey(one));

  @CollectionSize.Require(ZERO)
  public void testEmptySetPollFirst() {
    assertNull(navigableSet.pollFirst());
  }

  @CollectionSize.Require(ZERO)
  public void testEmptySetNearby() {
    assertNull(navigableSet.lower(e0()));
    assertNull(navigableSet.floor(e0()));
    assertNull(navigableSet.ceiling(e0()));
    assertNull(navigableSet.higher(e0()));
  }

  @CollectionFeature.Require(SUPPORTS_REMOVE)