jpa native query retrieve multiple entities

问题

I have a database with 4 tables:

company,staff,department,project

Company.java

@Entity
@Table(name = "company")
@SqlResultSetMapping(name = "COMPANY", entities = 
{
    @EntityResult(entityClass = Company.class),
    @EntityResult(entityClass = Staff.class)
})
...

GetEntity.java

EntityManagerFactory emf = Persistence.createEntityManagerFactory("GetEntityPU");
EntityManager em = emf.createEntityManager();

String query = "SELECT * 
                FROM company c 
                JOIN staff s 
                ON c.ID = s.companyID";
Query q = em.createNativeQuery(query, "COMPANY");
List<Object[]> list = q.getResultList();

From above code, I can retrieve all data from Company entity and Staff entity.

Now I want to retrieve all data from any 2 tables:
maybe all data for company, staff tables OR all data for staff, department tables

How should I control every entity in my query?
I really no ideas on how to do it.
Any ideas or useful source link are welcome.

回答1:

Mapping query to a bean could help you, check this out: query to bean

来源：https://stackoverflow.com/questions/30217569/jpa-native-query-retrieve-multiple-entities