带有基本值集合的休眠条件查询

Question

I am newbie in Hibernate especially in Criteria API and I can't find answer on my question.. Here is simplified domain class:

@Entity
public class HDNewsPost implements Serializable {
    @Id
    private Long id;

    //other fields
    //..    

    @ElementCollection
    @CollectionTable(name = "SD_SOLUTION.PBITSM_HD_NEWS_RECIPIENT_CODES",
            joinColumns = @JoinColumn(name = "POST_ID"))
    @Column(name="POSITION_CODE")
    private List<String> recipientCodes;

    //getters and setters
}

I need restriction for criteria that will satisfy if some value (String code) is present in recipientCodes collection.

Answer 1

I solved my task! Here is full criteria query with part where I have a problem:

final Criteria criteria = sessionFactory.getCurrentSession().createCriteria(HDNewsPost.class);
criteria.setFirstResult(startFrom);
criteria.setMaxResults(maxResults);
criteria.addOrder(Order.desc("publicationDate"));

if (code != null) {
    criteria.createAlias("recipientCodes", "rc", CriteriaSpecification.LEFT_JOIN);
    criteria.add(Restrictions.or(Restrictions.isEmpty("recipientCodes"),
        Restrictions.eq("rc.elements", code)));
}

return criteria.list();

I have found answer here https://docs.jboss.org/hibernate/orm/4.3/manual/en-US/html/ch17.html#querycriteria-collections

"For queryng a collection of basic values, we still create the Criteria object against the collection, but to reference the value, we use the special property "elements" . For an indexed collection, we can also reference the index property using the special property "indices"."

Also, when creating alias your need to specify sql LEFT_JOIN (the default is INNER_JOIN) or you will not get expected result, probably.