@Test
  public void shouldNotMapNulls_ClassLevel() {
    // given
    MapperFactory mapperFactory = new DefaultMapperFactory.Builder().mapNulls(true).build();

    mapperFactory.classMap(Container.class, Container.class).mapNulls(false).byDefault().register();

    Container a = new Container();
    Container b = new Container();

    b.longValue = 1L;
    b.stringValue = "TEST A";
    b.arrayOfString = new String[] {"a", "b", "c"};
    b.arrayOfInt = new int[] {1, 2, 3};
    b.listOfString = Arrays.asList("l1", "l2");
    b.map = Collections.singletonMap("key", (Object) "value");
    b.enumValue = Position.FIRST;

    // when
    mapperFactory.getMapperFacade().map(a, b);

    // then
    assertThat(b.stringValue).isNotNull();
    assertThat(b.arrayOfString).isNotNull();
    assertThat(b.arrayOfInt).isNotNull();
    assertThat(b.listOfString).isNotNull();
    assertThat(b.map).isNotNull();
    assertThat(b.enumValue).isNotNull();
  }