我有两个名为约会和客户端的实体，我想获取给定客户端的所有约会。当我尝试这样做时，我正在努力处理以下错误消息。
2022-05-24 13:30:41.685 WARN 23252 --- [ XNIO-3 task-1].m.m.a.ExceptionHandlerExceptionResolver：Resolve[org.springframe.da.InvalidDataAccessApiUsageException：参数值[1000]与预期类型[ma.mycom.myapp.domain.Client（n/a）]不匹配；嵌套异常是java.lang.IllegalArgumentException：参数值[1000]与预期类型[ma.mycom.myapp.domain.Client（n/a）]不匹配
以下是我的实体：
Client.java
@Entity
@Table(name = "CLIENTS")
@Cache(usage = CacheConcurrencyStrategy.READ_WRITE)
public class Client implements Serializable {
private static final long serialVersionUID = 1L;
@Id
@GeneratedValue(strategy = GenerationType.SEQUENCE, generator = "sequenceGenerator")
@SequenceGenerator(name = "sequenceGenerator")
@Column(name = "id")
private Long id;
//other attributes, getters, setters
}
Appointment.java
@Entity
@Table(name = "APPOINTMRNTS")
@Cache(usage = CacheConcurrencyStrategy.READ_WRITE)
public class Appointment implements Serializable {
private static final long serialVersionUID = 1L;
@Id
@GeneratedValue(strategy = GenerationType.SEQUENCE, generator = "sequenceGenerator")
@SequenceGenerator(name = "sequenceGenerator")
@Column(name = "id")
private Long id;
//other attributes
@ManyToOne
@JoinColumn(name = "ID_CLIENT")
private Client client;
//getters, setters
}
控制器，以及我如何调用查询：
List<Appointement> clientAppointements = appointementRepository.findAllByClient(idClient);
这里是AppointementRepository.java中使用的查询（我猜是问题的根源）
@Query(
name = "SELECT pe.* FROM APPOINTEMENTS pe INNER JOIN CLIENTS e ON pe.ID_CLIENT = e.ID WHERE e.id = ?1",
nativeQuery = true
)
List<Appointement> findAllByClient(Long idClient);
您的约会类没有任何类型的名为“客户端id”的字段，它只知道它拥有的Client实体。
在您的JPA存储库方法中，您只能使用实体的现有字段。
解决此问题的两种最标准的方法是：
@Entity
@Table(name = "CLIENTS")
@Cache(usage = CacheConcurrencyStrategy.READ_WRITE)
public class Client implements Serializable {
private static final long serialVersionUID = 1L;
@Id
@GeneratedValue(strategy = GenerationType.SEQUENCE, generator = "sequenceGenerator")
@SequenceGenerator(name = "sequenceGenerator")
@Column(name = "id")
private Long id;
@OneToMany(mappedBy = "client", fetch = FetchType.LAZY)
List<Appointment> appointments;
//other attributes, getters, setters
}
然后，您可以通过获取Client对象来简单地获得约会，然后简单地访问其约会字段。
List<Appointement> clientAppointements = clientRepository.findClientByField(field)
.getAppointments();
或者您甚至可以在存储库方法中获得客户端的约会：
// in your appointment repository
@Query(value = "SELECT c.appointments FROM Client c WHERE c.id = :cId")
List<Appointment> getAppointmentsById(Long cId);
// in your appointment repository
List<Appointment> findByClient(Client client);
// then you can fetch it anywhere
Client client = clientRepository.findById(cliendId);
List<Appointment> clientAppointments = appointmentRepository.findByClient(client);
