Wsrtjtyk

I'm trying to mapp Entity (TrainingEntity) to DTO, where one of the fields is a Set with ManyToMany reference to an AbstractEntity (CoachEntity) divided by Single Table into two subclasses: ExternalCoach and InternalCoach.

Both subclasses have different data, therefore require two different mappers.

@Entity

@Table(name = "TRAINING")

public class TrainingEntity extends AbstractEntity {



    @ManyToMany()

    @JoinTable(name = "TRAINING_EMPLOYEE", joinColumns = { @JoinColumn(name = "TRAINING_ID") }, inverseJoinColumns = {

            @JoinColumn(name = "COACH_ID") })

    private Set<CoachEntity> coachEntities;



@Column(nullable = false)

private TrainingType trainingType;



......some data....



}

Abstract Coach Entity

    @Entity

    @Table(name = "COACH")

    @DiscriminatorColumn(name = "TYPE", discriminatorType = DiscriminatorType.STRING)

    @Inheritance(strategy = InheritanceType.SINGLE_TABLE)

    public abstract class CoachEntity extends AbstractEntity {



 ......some data....



}

Coach Subclasses:

@Entity

@DiscriminatorValue("EXTERNAL")

public class ExternalCoachEntity extends CoachEntity {

 ......some data....

}







@Entity

@DiscriminatorValue("INTERNAL")

public class InternalCoachEntity extends CoachEntity {

 ......some data....

    }

One mapper for Abstract Coach class won't have acces to subclasses methods and fields, so I need two different for External and Internal. Than I would have to use them in TrainingMapper class, but (example of internal):

public class CustomTrainingMapper {



    public static TrainingDto toTrainingDto(TrainingEntity trainingEntity){

        if(trainingEntity == null){

            return null;

        }



        if(trainingEntity.getTrainingType().equals(TrainingType.INTERNAL)){

            Set<CoachEntity> coachEntities = trainingEntity.getCoachEntities();





            Set<CoachDto> coachDtos = CustomInternalCoachMapper.toDTOSet((Set<InternalCoachEntity>)coachEntities);

        }

I get:

  cannot cast from Set<CoachEntity> to Set<InternalCoachEntity>

Without cast it simply doesn't see mappers methods with subclass input.

The method toDTOSet(Set<InternalCoachEntity>) in the type CustomInternalCoachMapper is not applicable for the arguments (Set<CoachEntity>)

When in mapper I change method input to abstract Coach Class it doesn't see subclasses methods and fields.

Part of InternalMapper:

public class CustomInternalCoachMapper {



    public static CoachDto toCoachDto(InternalCoachEntity coachEntity) {

        if (coachEntity == null) {

            return null;

        }



        EmployeeDto employeeDto = CustomEmployeeMapper.toEmployeeDto(coachEntity.getEmployeeEntity());



        return new InternalCoachDto(coachEntity.getId(), coachEntity.getVersion(), coachEntity.getCreateDate(),

                coachEntity.getUpdateDate(), coachEntity.getName(), coachEntity.getSurname(), employeeDto);

    }

Is it possible to mapp this AbstractEntity Set into subclasses DTOs?
I also tried with AbstractDto for Coaches, but then I'm facing the same problem with no access to subclasses getters and setters.