JPA : How to convert a native query result set to POJO class collection

Question

I am using JPA in my project.

I came to a query in which I need to make join operation on five tables. So I created a native query which returns five fields.

Answer 1

All you need is a DTO with a constructor :

public class User2DTO implements Serializable {

    /** pode ser email ou id do Google comecando com G ou F para Facebook */
    private String username;

    private String password;

    private String email;

    private String name;

    private Integer loginType;

    public User2DTO(Object...fields) {
        super();
        this.username = (String) fields[0];
        this.name = (String) fields[1];
        this.email = (String) fields[2];
        this.password = (String) fields[3];
        this.loginType = (Integer) fields[4];
    }

and call it :

EntityManager em = repo.getEntityManager();
        Query q = em.createNativeQuery("SELECT u.username, u.name, u.email, 'blabla' as passe, login_type as loginType FROM users u");
        List objList = q.getResultList();
        List ooBj = objList.stream().map(User2DTO::new).collect(Collectors.toList());