@GwtCompatible
@NullMarked
@SuppressWarnings("JUnitIncompatibleType") // Many intentional violations here.
public class MapsTest extends TestCase {

  private static final Comparator<Integer> SOME_COMPARATOR = Collections.reverseOrder();

  public void testHashMap() {
    @SuppressWarnings("UseCollectionConstructor") // test of factory method
    HashMap<Integer, Integer> map = Maps.newHashMap();
    assertEquals(emptyMap(), map);
  }

@GwtCompatible
@NullMarked
@SuppressWarnings("JUnitIncompatibleType") // Many intentional violations here.
public class MapsTest extends TestCase {

  private static final Comparator<Integer> SOME_COMPARATOR = Collections.reverseOrder();

  public void testHashMap() {
    @SuppressWarnings("UseCollectionConstructor") // test of factory method
    HashMap<Integer, Integer> map = Maps.newHashMap();
    assertEquals(emptyMap(), map);
  }

  }

  /**
   * Returns a builder that creates immutable sorted maps whose keys are ordered by the reverse of
   * their natural ordering.
   */
  public static <K extends Comparable<?>, V> Builder<K, V> reverseOrder() {
    return new Builder<>(Ordering.<K>natural().reverse());
  }

  /**
   * A builder for creating immutable sorted map instances, especially {@code public static final}
   * maps ("constant maps"). Example: