@Test
 public void testHashCodeDifferentVertical() {
   assertNotEquals(
       HASH_CODE_MUST_BE_DISTINCT, built.hashCode(), builder.setVertical('x').build().hashCode());
 }
 @Test
 public void testToStringDifferentVertical() {
   assertNotEquals(
       TO_STRING_MUST_BE_DISTINCT, built.toString(), builder.setVertical('x').build().toString());
 }
 @Test
 public void testNotEqualToDifferentVertical() {
   assertNotEquals(
       NOT_EQUAL_TO_INSTANCE_WITH_DIFFERENT_VALUES, built, builder.setVertical('x').build());
 }