Question

我有以下实体，需要检索特定组中所有商店的名称列表，并在特定城市中拥有分支。我发现的大多数教程和文章都与创建这种类型的关系有关，但它们都不是关于检索的！

我多次更改了标准，但Hibernate为每个标准显示了不同的错误。代码的注释部分是我尝试过的部分，并且相应的抛出异常也写在每个部分的前面。

实体

@Entity
public class Store {
    @Id
    String id;
    String name;
    @JoinTable(name = "store_groups", joinColumns = { @JoinColumn(name = "id", nullable = false, updatable = false) }, inverseJoinColumns = { @JoinColumn(name = "code", nullable = false, updatable = false) })
    private Set<Group> groups = new HashSet<Group>(0);
    private Set<StoreAddress> storeAddresses = new HashSet<StoreAddress>(0);
   ....
}



@Entity
public class Group {
    @Id
    String code;
    @Column(nullable = false, unique = true)
    String name;
    @ManyToMany(fetch = FetchType.LAZY, mappedBy = "groups")
    Set<Store> storees = new HashSet<Store>(0);

}


@Entity
@Table(name = "StoreAddresses")
@AssociationOverrides({
        @AssociationOverride(name = "muJoinTable.store", joinColumns = @JoinColumn(name = "id", nullable = false)),
        @AssociationOverride(name = "myJoinTable.city", joinColumns = @JoinColumn(name = "cityCode", nullable = false)) })
public class StoreAddress {
    @EmbeddedId
    private StoreCitysId myJoinTable = new StoreCitysId();
        ...

}


@Embeddable
public class StoreCitysId {
    @ManyToOne
    private Store store;
    @ManyToOne
    private City city;
}

@Entity
public class City {
    @Id
    short code;
    @Column(nullable = false)
    String name;
        @OneToMany(fetch = FetchType.LAZY, mappedBy = "myJoinTable.city")
    private Set<StoreAddress> storeAddresses = new HashSet<StoreAddress>(
            0);
}

标准

        List<String> storees = (List<String>) sessionFactory
                .getCurrentSession()
                .createCriteria(Store.class)
                .setProjection(
                        Projections.property("name").as(
                                "storeName"))
                .createAlias("groups", "group")
                .createAlias("storeAddresses", "address")
                // .createAlias("address.myJoinTable.city", "city")

//              .createAlias("address.myJoinTable", "myJoinTable")
//              .createAlias("myJoinTable.city", "city") Error: Criteria objects cannot be created directly on components


                .setFetchMode("group", FetchMode.JOIN)
                .add(Restrictions.ilike("group.code", store))
                .add(Restrictions.eq("address.myJoinTable.cityCode",
                        1)).list(); //city.code -> Error: could not resolve property: cityCode of:com.example.entity.StoreAddress  address.myJoinTable.cityCode could not resolve property: myJoinTable.cityCode of:com.example.entity.StoreAddress

Answer 1

您的标准Restrictions.eq("address.myJoinTable.cityCode", 1)不会引用属性，而是引用列的名称。您可以改为使用address.myJoinTable.city并将值设置为session.load(City.class, 1) Restrictions.eq("address.myJoinTable.city", session.load(City.class, 1))

而且：

.createAlias("address.myJoinTable", "myJoinTable")
.createAlias("myJoinTable.city", "city")

应该是：

.createAlias("address.myJoinTable.city", "city")

Hibernate条件无法检索连接的值

1 个答案: