Creating an entity with a ManyToOne annotation-CodePudding

I'm creating an entity which has a ManyToOne relation to another one, it being multiple customers can belong to one company. Now I have my Customer entity defined as follows:

@Entity
@Table(name = "Customers")
data class Customer(
    @Id
    @GeneratedValue(strategy = GenerationType.IDENTITY)
    var customerId: Long? = null,
    var firstName: String,
    var lastName: String,
    var gender: String,
    @Column(insertable = false, updatable = false)
    var companyId: Long,
    @ManyToOne(targetEntity = Company::class, fetch = FetchType.LAZY)
    @JoinColumn(name = "companyId", referencedColumnName = "companyId")
    var company: Company? = null,
    var profilePicture: String,
    var email: String,
    var phone: String,
    var birthDay: String,
    var bio: String,
    var notifyByPhone: Boolean,
    var notifyByEmail: Boolean,
    var notifyBySms: Boolean,
    @UpdateTimestamp
    var updatedAt: LocalDateTime,
    @CreationTimestamp
    var createdAt: LocalDateTime
)

I use the following function from CustomerResource as an endpoint to persist the Customer:

    @Transactional
    @POST
    fun post(@Valid entity: Customer): Response = try {
        repository.persist(entity)
        created(entity)
    } catch (exc: Exception) {
        serverError(exc)
    }

Using Postman, I use the following JSON object to fire a request to the endpoint:

{
    "firstName": "Ricardo",
    "lastName": "de Vries",
    "gender": "male",
    "companyId": "200",
    "profilePicture": "test",
    "email": "[email protected]",
    "phone": "0612536263",
    "birthDay": "28-12-1995",
    "bio": "Nothing",
    "notifyByPhone": true,
    "notifyByEmail": true,
    "notifyBySms": true
}

I have a property called "company" which is being mapped to the Company the user belongs to, based on the companyId. I have a separate companyId field which is being mapped to the companyId field in the database.

When I want to create a new Customer, I'm including the companyId in the request. This succeeds and the Customer is being successfully created.

Now when I try to fetch that specific customer, I get the following

error: "org.hibernate.PropertyAccessException: Null value was assigned to a property [class org.acme.domains.core.models.entities.Customer.companyId] of primitive type setter of org.acme.domains.core.models.entities.Customer.companyId".

I don't really get why this error occurs. I would think that the Company which belongs to the Customer gets added afterwards whenever I fetch a specific Customer.

Does anybody know how to be able to add an entity this way?

CodePudding user response：

Do you have the proper getter and setters generated? It seems like the first request is failing to set the fields properly. I suggest you put a breakpoint to the controller that creates your customer and check if the field is being set like it should. Maybe you are passing the data in a wrong format etc. I can't say that from this information but you should debug that.

You can also put @NotNull validation on your fields to see if it fails to be set in object creation.

CodePudding user response：

You have mapped companyId as not insertable and not updatable, so it won't appear in the query.

Try change it to:

@Column(insertable = true, updatable = true)
Long companyId

What's happening, I think, it's that Hibernate ORM is creating the insert query with all the other values, except for this one. I would recommend enabling the log to check. You can do it in the configuration by setting:

hibernate.show_sql = true
hibernate.format_sql = true