[FIXED] Is it possible to use JpaRepository without entity?

Issue

Is it possible to use JpaRepository without entity? In this case, replacing it with a DTO.

as follows the example

 @Repository
public interface BffRepository extends JpaRepository<BffDTO, String> {

@Query(nativeQuery = true, value = "select\n"
        + "ent.name as enterprise_name, dep.name as department_name,\n"
        + "sq.name as squad_name, acc.firstname as job_owner_name,\n"
        + "tpt.name as test_template_name, job.name, job.job_blocked, job.job_removed,\n"
        + "job.bot_scm_branch, job.bot_scm_url, job.schedule_startdate,\n"
        + "job.expiration_date, job.timestamp,job.uuid,job.schedule_starttime,\n"
        + "tpt.job_execution_timeout\n"
        + "from portal.jobs job\n"
        + "left join portal.enterprises ent on (ent.uuid = job.enterprise_id)\n"
        + "left join portal.departments dep on (dep.uuid = job.department_id)\n"
        + "left join portal.squads sq on (sq.uuid = job.squad_id)\n"
        + "left join portal.accounts acc on (acc.uuid = job.job_owner)\n"
        + "left join portal.test_plan_templates tpt on (tpt.uuid = job.template_id) where\n"
        + "job.job_owner = ?1 and job.job_removed = false order by timestamp desc;")
List<BffDTO>buscarPorJobOwner(String jobOwner);

Are there alternatives for this case?

NOTE: the DTO is already mapped, but I would not like to create a view to transform this DTO into an Entity.

I already validated this topic, but without major advances Use JpaRepository interaction style without entity

i'm trying this

Interface -

public interface BffDTOInterface2 {

String uuid();

String enterprise_name();

String department_name();

String squad_name();

String job_owner_name();

String test_template_name();

String name();

Boolean job_blocked();

Boolean job_removed();

String bot_scm_branch();

String bot_scm_url();

String schedule_startdate();

String expiration_date();

String timestamp();

String schedule_starttime();

Integer job_execution_timeout();

@Transient
String status();

}

I'm having this error

Caused by: java.lang.IllegalArgumentException: Not a managed type: interface br.com.cloud.api.domain.dto.BffDTOInterface2

Solution

Is it possible to use JpaRepository without entity?

No, it is not, and it would completely defeat the purpose of JPA, by definition.

JPA is the persistence specification that enables ORM - Object Relational Mapping - that is, you map Java objects to database tables' entries/rows, and Java types to database tables, respectively.

DTO (Data Transfer Object) has nothing to do with ORM, and it serves different purpose (I recommend you to read this article for DTO vs. Entity matter) - transferring data through Java objects - and it usually serves the middle layer, for converting persistent objects(@Entitys) into objects to be used in the web layer (DTOs), and vice versa.

If you really want to avoid persistence layer models (@Entitys), you may go for JDBC abstractions (e.g. Spring Data JDBC), native queries, JPQL, HQL, or a bare JDBC API (which I wouldn't recommend).

Answered By - Giorgi Tsiklauri
Answer Checked By - Willingham (JavaFixing Volunteer)