code: protected final List<String> getStringIdList(final SingularAttribute<T, String> property) {
  		final CriteriaQuery<String> criteria = getCriteriaBuilder().createQuery(String.class);
  		final Root<T> root = criteria.from(persistentClass);
  		criteria.select(getCriteriaBuilder().construct(String.class,root.get(property)));
  		return getEntityManager().createQuery(criteria).getResultList();
  	}
docs: Gets the string id list.
  
  @param property
  the property
  @return the string id list