Question

我正在尝试JPA，但我不能按照我理解的方式工作。

它是Order和OrderInvoice类之间的onetoone双向映射，这是必需的协会

我的实体被标记为此

@Entity
@Table(name = "Orders")
public class Order {
    @Id
    @GeneratedValue
    @Column(name = "ORDER_ID")
    private int orderId;

    @OneToOne(optional=false,cascade=CascadeType.ALL, mappedBy="order", targetEntity=OrderInvoice.class)
    private OrderInvoice invoice;
}

@Entity
@Table(name = "ORDER_INVOICE")
public class OrderInvoice {
    @Id
    @GeneratedValue
    @Column(name = "INVOICE_ID", nullable = false)
    private int invoiceId;

    @OneToOne(optional = false)
    @JoinColumn(name="ORDER_ID")
    private Order order;
}

我的测试类是这样的。

@Test
public void createOrder() {
    Order order = createOrderImpl();
    assertNotNull(order);
}

private Order createOrderImpl() {
    OrderInvoice orderInvoice = new OrderInvoice(new Date(), 100.0, null,
            null, new Date());
    Order order = new Order(100.0, "JOHN Doe's Order", new Date(), new Date(),orderInvoice);
    orderDao.create(order);
    return order;
}

但是当我运行我的测试时，我遇到了以下问题

javax.persistence.PersistenceException: org.hibernate.PropertyValueException: not-null property references a null or transient value: order.OrderInvoice.order
    at org.hibernate.ejb.AbstractEntityManagerImpl.throwPersistenceException(AbstractEntityManagerImpl.java:614)

Caused by: org.hibernate.PropertyValueException: not-null property references a null or transient value: order.OrderInvoice.order
    at org.hibernate.engine.Nullability.checkNullability(Nullability.java:95)

Answer 1

尝试

orderInvoice.setOrder(order);
orderDao.create(order);

使用JPA onetoone映射不是Null属性异常

1 个答案: