How do I query based on fields of EmbeddedId using JPA Criteria?

Roland Roberts :

I've spent the last couple of hours trying to figure this out, mostly by searching since I figure someone has already done it, but I'm not finding an answer that works for me.

Here's an on-the-fly translation of my code to something I can put in public.

@Entity @Table(name="result")
public class Result implements Serializable {
    @Embeddable
    public static class ResultPK implements Serializable {
        @Column(name="result_date", nullable=false)
        @Type(type="com.example.HibernateUTC$LocalDateType") // <- UserType
        public LocalDate resultDate;
        @Column(name="name", nullable=false)
        public String name;
        @Column(name="category", nullable=false)
        public String category;
        public ResultPK() {}
        public ResultPK(Date resultDate, String name, String category) {
            this.resultDate = resultDate;
            this.name = name;
            this.category = category;
        }
        // ...more code for hashCode/equals, no setters or getters...
    }

    @EmbeddedId
    @AttributeOverrides({
            @AttributeOverride(name="resultDate", column=@Column(name="result_date", nullable = false)),
            @AttributeOverride(name="name", column=@Column(name="name", nullable=false)),
            @AttributeOverride(name="category", column=@Column(name="category", nullable = false)),
            })
    private ResultPK resultId;
    @Column(name="r_square")
    private Double rSq;
    @Column(name="p_value")
    private pValue;

    // ... more code for other fields, setters, getters, but nothing else; vanilla pojo...
}

I have a DAO where queries are hiding; the method that I'm calling is this

@Repository("resultDAO")
public class ResultDAOImpl extends AbstractBaseDAO<Result> implements ResultDAO {
    // boilerplate for intializing base class and other queries
    @Override
    public List<Result> findDateRange(String category, String name, LocalDate begDate, LocalDate endDate) {
        EntityManager em = entityManagerFactory.createEntityManager();
        CriteriaBuilder cb = em.getCriteriaBuilder();
        CriteriaQuery<Result> q = cb.createQuery(Result.class);
        Root<Result> root = q.from(Result.class);
        Predicate catMatch = cb.equal(root.get("resultId.category"), category);
        Predicate nameMatch = cb.equal(root.get("resultId.name"), name);
        Predicate dateRange = cb.between(root.get("resultId.resultDate"), begDate, endDate);
        q.select(root).where(cb.and(catMatch, nameMatch, dateRange));
        return em.createQuery(q).getResultList();
    }
}

When I attempt to run the code that executes that query, I end up with an error

Exception in thread "main" java.lang.IllegalArgumentException: Unable to locate Attribute  with the the given name [resultId.category] on this ManagedType [com.example.Result]

Some of the similar questions I've found made it look like I needed to use the resultPK or ResultPK in the query. I've tried those, no joy. I have no idea how to specify the fields in the key for the query, or if I need something totaly different to this. I really need a clue...

I'm using Spring 4.3.8.RELEASE and Hibernate 4.3.11.Final, Java 8 (hence the UserType to handle LocalDate).

Edited to correct some inconsistencies in my transcription of the actual code.

alex valuiskyi :

You should modify your predicates this way:

 Predicate catMatch = cb.equal(root.get("resultId").get("category"), category);
 Predicate nameMatch = cb.equal(root.get("resultId").get("name"), name);
 Predicate dateRange = cb.between(root.get("resultId").get("resultDate"), begDate, endDate);

By the way no need to use cb.and inside of where statement. You can make the code a bit shorter using

q.select(root).where(catMatch, nameMatch, dateRange);