在服务层中注入自定义存储库实现

Question

I am written a custom JPA implementation using the Spring JPA documentation as reference, and I wish to inject aforementioned implementation in a service layer, but I can not figure out what I am doing wrong. I have also gone through the following documentation as well . My application is a Spring boot application.

The documentation does not say how to initialise my custom repository implementation. I have tried to follow the following instructions .

My Service layer.

@Service
public class ProfileService implements IProfileService {

  @Autowired
  private IQuizRepository quizRepository;

  . . . . Some methods defined here. . . . 
}

My JPA interface

@NoRepositoryBean
public interface IQuizRepository extends JpaRepository<Quiz, Long> {

  Quiz registerQuiz();

}

Concrete class

public class QuizRepository extends SimpleJpaRepository<Quiz, Long> implements IQuizRepository {

 @PersistenceContext
 private EntityManager em;

 public QuizRepository(Class<Quiz> clazz, EntityManager em) {
   super(clazz, em);
 }

  /**
   * Initialises and returns a quiz attempt.
   */
  @Override     
  public Quiz registerQuiz() {
    String uniqueKey = UUID.randomUUID().toString().replaceAll("-", "");
    Quiz quiz = new Quiz();
    quiz.setQuizId(uniqueKey);
    Score score = new Score();
    quiz.setScore(score);
    score.setQuiz(quiz);
    this.save(quiz);
    return quiz;
  }

}

When I don't annotate QuizRepository concrete class with Repository , then I get the following error.

***************************
APPLICATION FAILED TO START
***************************

Description:

Field quizRepository in com.myproject.service.ProfileService required a bean of type 'com.myproject.repository.IQuizRepository' that could not be found.


Action:

Consider defining a bean of type 'com.myproject.repository.IQuizRepository' in your configuration.

But when I annotate QuizRepository with @Repository , then I get the following error

***************************
APPLICATION FAILED TO START
***************************

Description:

Parameter 0 of constructor in com.myproject.repository.QuizRepository required a bean of type 'java.lang.Class' that could not be found.


Action:

Consider defining a bean of type 'java.lang.Class' in your configuration.

My project has a combination of JPA interfaces inheriting from JPA repository, and concrete implementations.

Answer 1

Sounds like your constructor needs to have these exact two parameters:

public QuizRepository(JpaEntityInformation<Quiz, Long> entityInformation, EntityManager entityManager) {
    super(entityInformation, entityManager);
    this.entityManager = entityManager;
}

instead of public QuizRepository(Class<Quiz> clazz, EntityManager entityManager)