Details with @Autowired and Down object

Question

Details with @Autowired and Down object

Navigation

#1 by (2 votes)

0

There is a conflict of concepts with me.

I have here a service called: AtividadeService

There are some lines that call my attention:

import com.dendetech.entity.Atividade;

Why import the entity? If it only works for AtividadeRepository ?

@Service
public class AtividadeService {

    @Autowired
    private AtividadeRepository atividadeRepository;

    private AtividadeDAO atividadeRepository = new AtividadeDAO();

Why does a new object of type AtividadeDown , if it already has @Autowired ?

(Remained omitted).

java spring jpa

asked by anonymous 10.09.2015 / 16:00

1 answer

Create a single change function for multiple CSS selectors in Jquery Scrollbar on a select

score 2 · Answer 1

In fact, this is not making much sense here:

@Autowired
private AtividadeRepository atividadeRepository;

private AtividadeDAO atividadeRepository = new AtividadeDAO();

Incidentally, it would not even compile since you are declaring two different objects with the same name within the scope of the same class.

Another thing is that you are probably making some confusion of concepts. Either you use a repository, or you use a DAO. Repositories are entities that work at the collection level. DAOs are entities that work at the level of database technology.

In addition, the difference between Data Access Object (DAO) and Data Access Layer (DAL) is not just one letter: DAO is the object that is part of a DAL. Normally, both DAO and a repository return DTO ( Data Transfer Object >) objects.

Having this understood, we can move to @Autowired .

@Autowired is the annotation for Dependency Injection . It indicates to the framework that the marked object will be managed by the framework (its entire lifecycle). It makes sense for a Service , but it does not make much sense to an entity, since usually an entity (most of the time) is an anemic object that does not require life cycle management (DTO definition).

So in this case, I think it would be interesting to remove the DAO statement.