@Override
public BaseResponse getNavProperty(String entitySetName, OEntityKey entityKey, String navProp, QueryInfo queryInfo) {
final EdmEntitySet ees = metadata.getEdmEntitySet(entitySetName);
EdmEntityType eet = ees.getType();
EdmNavigationProperty enp = eet.findNavigationProperty(navProp);
if (enp == null) {
throw new NotFoundException("EdmNavigationProperty " + navProp + " not found.");
}
final EdmEntitySet eesNavProp = metadata.getEdmEntitySet(enp.getToRole().getRole());
EdmMultiplicity relMultiplicity = enp.getRelationship().getEnd2().getMultiplicity();
Entity entity = findEntity(entitySetName, entityKey);
Object navPropValue = entity.getProperties().get(navProp);
if (navPropValue == null) {
return Responses.entities(new ArrayList<OEntity>(), eesNavProp, 0, null);