@EmbeddedId : is not mapped as an embeddable

Question

I got an Eclipse error with : @EmbeddedId.

This is the entity :

@Entity
@Table(name = "PERSON")
public class Person implements Serializable {

    @EmbeddedId
    private PersonPK PersonPK;

    @Column(name = "AGE")
    private int age;
}

And the embeddable class :

@Embeddable
public class PersonPK implements Serializable {

    @Column(name = "FIRSTNAME")
    private String firstName;

    @Column(name = "LASTNAME")
    private String lastName;

    public PersonPK() {
    }
}

Eclipse show me this error : PersonPK is not mapped as an embeddable

Can you tell me why and how to fix that ?

Answer 1

Old question, I know, but having had--and solved--this very problem this morning, here's another possibility:

In your persistence.xml file, if exclude-unlisted-classes is set to true, then you need to have the @Embeddable class listed as a managed class in the persistence unit. So in the above case, you would do something like this:

<persistence-unit name="default" transaction-type="JTA">
    <!-- ..... -->
    <class>com.example.foobar.Person</class>
    <class>com.example.foobar.PersonPK</class>
    <exclude-unlisted-classes>true</exclude-unlisted-classes>
    <!-- ..... -->
</persistence-unit>

Answer 2

You could also disable JPA validation for builds.

Right-click on the project and select properties. Select Validation and check Enable project specific settings. Uncheck JPA Validator. Clean the project.

Source: Problem with JPA Project in Eclipse - error in class annotated @Entity: Table "xxx" cannot be resolved