spring::lateinit 属性 userRepo 尚未初始化

Question

DataTable.kt

class DataTable(private val param: MultiValueMap<String, String>, private val searchField: Array<String>) {
    @Autowired
    private val userService: UserService = UserService()

    private fun getAllCnt(): Int {
        return userService.countAll()
    }

UserRepo.kt

@Repository
interface UserRepo: JpaRepository<User, Long> {
    @Query(value="SELECT COUNT(*) FROM users", nativeQuery=true)
    fun countAll(): Int
}

UserService.kt

@Service
class UserService {
    @Autowired
    private lateinit var userRepo: UserRepo

    fun countAll(): Int {
        return userRepo.countAll()
    }
}

---

error

lateinit property userRepo has not been initialized

maybe I think not define userRepo. but I don't know how to define userRepo.

Answer 1

Why used lateinit ? doesn't seem necessary

Try fixing it like this

Before change

@Service
class UserService {
    @Autowired
    private lateinit var userRepo: UserRepo

    fun countAll(): Int {
        return userRepo.countAll()
    }
}

After

@Service
class UserService(
    private val userRepo: UserRepo
) {

    fun countAll(): Int {
        return userRepo.countAll()
    }
}