Inject Repository into RepositoryCustom

[niroussel]

Until SpringBoot 2.4.1, it was possible to inject a repository into its custom implementation.

This was really useful to avoid having several repositories for the same Entity.

For example, this doesn't work anymore:

• <package 'data'>
  • UserRepository.java
  • <packages 'data.custom'>
    • UserRepositoryCustom.java
    • UserRepositoryImpl.java

With :

public class UserRepositoryImpl implements UserRepositoryCustom {

    @Autowired
    private UserRepository repo;

    public List<User> veryComplicatedSearch() {
        ....
        ....
        return repo.findAll(veryComplicatedPredicate);
    }
}

This will lead to this exception:

      ↓
┌─────┐
|  userRepositoryImpl (field private data.UserRepository data.custom.UserRepositoryImpl.repo)
└─────┘


Action:

Relying upon circular references is discouraged and they are prohibited by default. Update your application to remove the dependency cycle between beans. As a last resort, it may be possible to break the cycle automatically by setting spring.main.allow-circular-references to true.

[mp911de]

In short, this isn't possible as repository fragments are required to create the repository instance. You can either work around it by using @Lazy or ObjectProvider (or look up the repository instance at the time of using it via ApplicationContext).

[RadouaneRoufid]

What's the correct approach to address this problem without using the workarounds above ?

What if the fragment needs the repository as mentioned by @niroussel ?

public class UserRepositoryImpl implements UserRepositoryCustom {

    @Autowired
    private UserRepository userRepository;

    @Override
    public List<User> searchByCriteria(UserSearchCriteria searchCriteria) {
        return userRepository.findAll(UserSpecifications.build(searchCriteria));
    }
}

[s-volkov-1]

What's the correct approach to address this problem without using the workarounds above ?

Maybe one of:

• using default methods inside UserRepository interface
• creating UserService/UserSearchService, which hosts additional logic for working with repository

[samuelpsfung]

I've this workaround

@Repository
public class UserRepositoryImpl implements UserRepositoryCustom {

    @PersistenceContext
    private EntityManager entityManager;

    private JpaSpecificationExecutor<User> executor;

    @PostConstruct
    public void init() {
        executor = new SimpleJpaRepository<User, String>(User.class, entityManager);
    }

    @Override
    public List<User> searchByCriteria(UserSearchCriteria searchCriteria) {
        return executor.findAll(UserSpecifications.build(searchCriteria));
    }
}

creating UserService/UserSearchService, which hosts additional logic for working with repository

i think the query logic should be kept in the repository layer; should not be leaked to the service layer.