ticker.advance(1, MILLISECONDS);
    assertThat(keySet).containsExactly(3, 4, 5, 6, 7, 8, 9, 0);

    // asMap.put saves 3
    cache.asMap().put(3, -3);
    ticker.advance(1, MILLISECONDS);
    assertThat(keySet).containsExactly(4, 5, 6, 7, 8, 9, 0, 3);

    // asMap.replace saves 4
    cache.asMap().replace(4, -4);
    ticker.advance(1, MILLISECONDS);
    assertThat(keySet).containsExactly(5, 6, 7, 8, 9, 0, 3, 4);

/**
 * Simple utility for when you want to create a {@link TearDown} that may throw an exception but
 * should not fail a test when it does. (The behavior of a {@code TearDown} that throws an exception
 * varies; see its documentation for details.) Use it just like a {@code TearDown}, except override
 * {@link #sloppyTearDown()} instead.
 *
 * @author Luiz-Otavio Zorzella
 * @since 10.0
 */
@GwtCompatible

    }
  }

  private static boolean equal(@Nullable Object a, @Nullable Object b) {
    return a == b || (a != null && a.equals(b));
  }

  // This one-liner saves us from some ugly casts
  protected Entry<K, V> entry(K key, V value) {
    return Helpers.mapEntry(key, value);
  }

  @Override
  protected void expectContents(Collection<Entry<K, V>> expected) {

 * even when the result of the comparison is already known from previous {@code .compare} calls.
 * That can be expensive.
 *
 * @author Mark Davis
 * @author Kevin Bourrillion
 * @since 2.0
 */
@GwtCompatible
@ElementTypesAreNonnullByDefault
public abstract class ComparisonChain {
  private ComparisonChain() {}

    }
  }

  private static boolean equal(@Nullable Object a, @Nullable Object b) {
    return a == b || (a != null && a.equals(b));
  }

  // This one-liner saves us from some ugly casts
  protected Entry<K, V> entry(K key, V value) {
    return Helpers.mapEntry(key, value);
  }

  @Override
  protected void expectContents(Collection<Entry<K, V>> expected) {

    ticker.advance(1, MILLISECONDS);
    assertThat(keySet).containsExactly(3, 4, 5, 6, 7, 8, 9, 0);

    // asMap.put saves 3
    cache.asMap().put(3, -3);
    ticker.advance(1, MILLISECONDS);
    assertThat(keySet).containsExactly(4, 5, 6, 7, 8, 9, 0, 3);

    // asMap.replace saves 4
    cache.asMap().replace(4, -4);
    ticker.advance(1, MILLISECONDS);
    assertThat(keySet).containsExactly(5, 6, 7, 8, 9, 0, 3, 4);

   * This is because the {@code forTree()}-based implementations don't keep track of visited nodes,
   * and therefore don't need to call `equals()` or `hashCode()` on the node objects; this saves
   * both time and space versus traversing the same graph using {@code forGraph()}.
   *
   * <p>Providing a graph to be traversed for which there is more than one path from the start
   * node(s) to any node may lead to:

        .addEqualityGroup(Collections.reverseOrder())
        .testEquals();
  }

  public void testReverseOfReverseSameAsForward() {
    // Not guaranteed by spec, but it works, and saves us from testing
    // exhaustively
    assertSame(numberOrdering, numberOrdering.reverse().reverse());
  }

  private enum StringLengthFunction implements Function<String, Integer> {
    StringLength;

        .addEqualityGroup(Collections.reverseOrder())
        .testEquals();
  }

  public void testReverseOfReverseSameAsForward() {
    // Not guaranteed by spec, but it works, and saves us from testing
    // exhaustively
    assertSame(numberOrdering, numberOrdering.reverse().reverse());
  }

  private enum StringLengthFunction implements Function<String, Integer> {
    StringLength;

    /** Gets the key for this entry. */
    K getKey();

    /** Gets the value for the entry. */
    V getValue();
  }

  /*
   * Note: the following classes have a lot of duplicate code. It sucks, but it saves a lot of
   * memory. If only Java had mixins!
   */

  /** Base class for {@link InternalEntry} implementations for strong keys. */
  abstract static class AbstractStrongKeyEntry<K, V, E extends InternalEntry<K, V, E>>