java - How to map the result set of a JPA NativeQuery to a POJO using SqlResultSetMapping

Question

I am attempting to map the results of a Native query to a POJO using @SqlResultSetMapping with @ConstructorResult. Here is my code:

@SqlResultSetMapping(name="foo",
    classes = {
        @ConstructorResult(
                targetClass = Bar.class,
                columns = {
                    @ColumnResult(name = "barId", type = Long.class),
                    @ColumnResult(name = "barName", type = String.class),
                    @ColumnResult(name = "barTotal", type = Long.class)
                })
    })

public class Bar {

private Long barId;
private String barName;
private Long barTotal;

...

And then in my DAO:

Query query = em.createNativeQueryBar(QUERY, "foo");
... set some parameters ...
List<Bar> list = (List<Bar>) query.getResultList();

I have read that this functionality is only supported in JPA 2.1, but that is what I am using. Here's my dependency:

        <dependency>
            <groupId>org.hibernate.javax.persistence</groupId>
            <artifactId>hibernate-jpa-2.1-api</artifactId>
            <version>1.0.0.Final</version>
        </dependency>

I found a couple of resources, including this one: @ConstructorResult mapping in jpa 2.1. But I am still not having any luck.

What am I missing? Why can't the SqlResultSetMapping be found?

javax.persistence.PersistenceException: org.hibernate.MappingException: Unknown SqlResultSetMapping [foo]

Answer 1

@SqlResultSetMapping annotation should not be put on a POJO. Put it at (any) @Entity class. "Unknown SqlResultSetMapping [foo]" tells you, that JPA provider doesn't see any mapping under name 'foo'. Please see another answer of mine for the correct example

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