首页 > 解决方案 > 检索新列表具有先前保存的不完整关联对象

问题描述

我正在构建一个小的 Primefaces 应用程序(Joinfaces 3.2.4、Hibernate 和 H2 数据库)。我想注册汽车并立即(在同一视图中)刷新汽车p:dataTable。一切正常,表格内容随着最近添加的汽车而更新,但一列(显示人员相关数据)为空。

实体:

@Data
@NoArgsConstructor
@Entity
@Table(name="person")
public class Person extends DbAudit implements Serializable{

    //Id and another fields

    @OneToMany(cascade = CascadeType.ALL, mappedBy = "person")
    private List<DbCar> cars;
}

@Data
@NoArgsConstructor
@Entity
@Table(name="car")
public class Car extends DbAudit implements Serializable{

    //Id and another fields

    @ManyToOne(optional = false)
    @JoinColumn(name = "FK", referencedColumnName = "PK_PER")
    private DbPerson person;
}

存储库:

@Repository
public interface CarDao extends JpaRepository<DbCar, Integer>{
}

服务:

@Service
public class CarServiceImpl implements CarService{

    private @Autowired CarDao carDao;

    @Override
    @Transactional(readOnly = false)
    public DbCar save(DbCar car) {
        return carDao.saveAndFlush(car);
    }

    @Override
    @Transactional(readOnly = true)
    public List<DbCar> findAll() {
        return carDao.findAll();
    }

}

控制器:

@Controller(value = "carController")
@ViewScoped
public class CarController implements Serializable{

    private @Autowired CarService carService;

    @Getter
    @Setter
    private Car car;

    @Getter
    @Setter
    private List<Car> cars;

    public void loadCars() {
        cars = carService.findAll();
    }

    public void save() {
        carService.save(car);

        // Reset car object

        loadCars();
    }
}

XHTML 页面:

<!-- Here is register form including a selectOneMenu for choose the Person who owns the car -->

<p:commandButton value="Save" actionListener="#{carController.save}" update="tblCar">
    <p:confirm header="..." message="..." icon="ui-icon-alert" />
</p:commandButton>

<p:confirmDialog global="true">
    ...
</p:confirmDialog>

<!-- Here is cars p:datatTable (value=#{carController.cars}) -->

我注意到,当重新加载列表时,最近保存的汽车有不完整的 Person 对象(除 id 外,所有字段均为空)。然后,如果我保存另一辆车,问题就出在新车上,而以前的汽车不再有问题。但是当页面重新加载 (F5) 时,所有信息都会正确获取。

标签: spring-bootjsfprimefacesspring-data-jpa

解决方案


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