### Question:
LiteralPropertiesDescription extends BaseDetachedPropertiesDescription { @Override protected Predicate undefined() { return Predicates.undefined(); } LiteralPropertiesDescription(Entity entity);  LiteralPropertiesDescription(Map<String, Predicate> predicates);   }### Answer:
@Test public void shouldReturnUndefinedForNonExistingKeys() { PropertiesDescription description = literal(); assertEquals(undefined(), description.get("non-existing")); }