在由JoinColumn注释的字段上编写CRUDRepository的findBy()方法

Question

我对Spring JPA有点新意,所以如果我的问题听起来很基本,我会提前道歉.我有2个实体对象:OrderInfo和PersonInfo.课程如下:

@Entity
@Table(name="order_info")
@NamedQuery(name="OrderInfo.findAll", query="SELECT o FROM OrderInfo o")
public class OrderInfo implements Serializable {

    @Column(name="order_number")
    private String orderNumber;

    //bi-directional many-to-one association to PersonInfo
    @ManyToOne
    @JoinColumn(name="person_id")
    private PersonInfo personInfo;

    public String getOrderNumber() {
        return this.orderNumber;
    }

    public void setOrderNumber(String orderNumber) {
        this.orderNumber = orderNumber;
    }

    public PersonInfo getPersonInfo() {
        return this.personInfo;
    }

    public void setPersonInfo(PersonInfo personInfo) {
        this.personInfo = personInfo;
    }


}

而Person实体:

@Entity
@Table(name="person_info")
@NamedQuery(name="PersonInfo.findAll", query="SELECT p FROM PersonInfo p")
public class PersonInfo implements Serializable {

    //bi-directional many-to-one association to OrderInfo
    @OneToMany(mappedBy="personInfo")
    private List<OrderInfo> orderInfos;

    public List<OrderInfo> getOrderInfos() {
        return this.orderInfos;
    }

    public void setOrderInfos(List<OrderInfo> orderInfos) {
        this.orderInfos = orderInfos;
    }

    public OrderInfo addOrderInfo(OrderInfo orderInfo) {
        getOrderInfos().add(orderInfo);
        orderInfo.setPersonInfo(this);

        return orderInfo;
    }

    public OrderInfo removeOrderInfo(OrderInfo orderInfo) {
        getOrderInfos().remove(orderInfo);
        orderInfo.setPersonInfo(null);

        return orderInfo;
    }

}

这两个类是使用JPA的create entityfromtable选项在Eclipse中自动生成的.

现在,我正在尝试编写一个CRUDRepository来获取OrderInfo,并给出orderNumber和personId.如果我在OrderInfo对象中有一个personId字段,我可以编写类似的东西

@Repository
public interface OrderRepository extends CrudRepository<OrderInfo, Integer>{
    public OrderInfo findByPersonIdAndOrderNumber(@Param("personId") Long personId, @Param("orderNumber") String orderNumber);

}

但是,现在OrderInfo实体没有personId.相反,它有一个Person的引用(同样,我没有编写实体类.它们是由Eclipse自动生成的).我该如何编写findBy()方法呢？

提前致谢.

Answer 1

我找到了另一种解决方案,假设我们有一个用户实体和消息实体.

@Entity
public class Message {

    @Id
    @GeneratedValue(strategy = GenerationType.AUTO)
    private Long id;

    @NotNull
    @Type(type="org.jadira.usertype.dateandtime.joda.PersistentDateTime")
    private DateTime date;

    @ManyToOne
    @JoinColumn(name = "id_user_sender")
    private User userSender;

    @NotNull
    private Long idUserReceiver;

    @NotNull
    @Length(min = 10)
    private String message;

    @NotNull
    private String idConversation;

    @NotNull
    Boolean userHasRead;

    //Getters and Setters

}



@Entity
public class User implements Serializable {

    @Id
    @GeneratedValue(strategy = GenerationType.AUTO)
    private Long id;

    //Some other properies like email,name etc
    //Getters and setters
}

现在我需要通过id_user_sender找到所有消息.

public interface MessageRepository extends JpaRepository<Message,Long>,TransactionRepositoryCustom {
    List<Message> findByUserSenderId(Long idUser);
}

说明:在Message实体中,我有一个名为'userSender'的用户对象.userSender有一个名为"id"的字段.

所以'findByUserSenderId'在userSender对象中搜索id.

另一种可能性是将完整的User对象传递给消息库,如下例所示:( User对象必须只包含id)

public interface MessageRepository extends JpaRepository<Message,Long>,TransactionRepositoryCustom {
   List<Message> findByUserSender(User user);
}

Answer 2

使用 JPQL 查询：

@Query("select o from OrderInfo o where o.orderNumber = :orderNumber"
       + " and o.personInfo.id = :personId")