mappedBy 是指 Class 名称还是 Table 名称？

Question

例如，当我们在@OneToMany 中使用mappedBy 注释时，我们提到了Class 名称还是Table 名称？

一个例子：

@Entity
@Table(name = "customer_tab")
public class Customer {
   @Id @GeneratedValue public Integer getId() { return id; }
   public void setId(Integer id) { this.id = id; }
   private Integer id;

   @OneToMany(mappedBy="customer_tab")
   @OrderColumn(name="orders_index")
   public List<Order> getOrders() { return orders; }

}

那么这两个哪个是正确的？ :

@OneToMany(mappedBy="customer_tab")
@OneToMany(mappedBy="Customer") ?

谢谢！

Answer 1

两者都不正确。来自 documentation:

mappedBy
public abstract java.lang.String mappedBy
The field that owns the relationship. Required unless the relationship is unidirectional.

mappedBy 注释表示它标记的字段由关系的另一方拥有，在您的示例中是一对多关系的另一方。我不确切知道你的架构是什么，但以下 class 定义是有意义的：

@Entity
@Table(name = "customer_tab")
public class Customer {
    @OneToMany(mappedBy="customer")
    @OrderColumn(name="orders_index")
    public List<Order> getOrders() { return orders; }

}

@Entity
public class Order {
    @ManyToOne
    @JoinColumn(name = "customerId")
    // the name of this field should match the name specified
    // in your mappedBy annotation in the Customer class
    private Customer customer;
}

mappedBy 是指 Class 名称还是 Table 名称？

mappedBy refers to the Class Name or to the Table Name?

java

mapping

hibernate

jpa

one-to-many