java - mappedBy 指的是类名还是表名？

Question

例如，当我们在@OneToMany 中使用mappedBy 注解时，我们是否提到了类名或表名？

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呢？ :

• @OneToMany(mappedBy="customer_tab")
• @OneToMany(mappedBy="客户") ?

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。我不确切知道你的模式是什么，但以下类定义是有意义的:

@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;
}