使用 Spring Data JPA 的派生查询

Question

My task is to compose a query without using the @Query annotation. If you use select , it will work, but if you use update , then the exception pointing to the line query.executeUpdate();

javax.persistence.TransactionRequiredException: Executing an update/delete query

CustomUserRepository:

@Repository
public interface CustomUserRepository {
    List<User> findByUniqueId(String uniqueId,UserStatus role);
}

CustomUserRepositoryImpl:

@Autowired
private EntityManager entityManager;

@Override
public List<User> findByUniqueId(String uniqueId, UserStatus role) {
        Query query = entityManager.createQuery("update User u set u.userStatus=:userStatus where u.unique=:unique");
        query.setParameter("userStatus", role).setParameter("unique", uniqueId);
        query.executeUpdate();
        return query.getResultList();
}

ControllerFour:

@Autowired
private UserRepository userRepository;

@PostMapping
public String replaceStatusPost (@RequestParam("uniqueid") String uniqueid, @RequestParam("userstatus") UserStatus userstatus, Model model) {
        List <User> user = userRepository.findByUniqueId(uniqueid, userstatus);
        model.addAttribute("attz", user);
        return "replaceStatus";
}

Answer 1

I think that message says all:

javax.persistence.TransactionRequiredException: Executing an update/delete query

When using EntityManager to execute any update operation (update/insert/delete) you have to do that within transaction.

Therefore your code should look like:

entityManager.getTransaction().begin();
// execute any operation on entityManager
entityManager.getTransaction().commit();

Side note, it is generally recommended to use @PersistenceContext instead of @Autowired as that gives more control over the injected EntityManager (especially if you have multiple DB configurations).