按主键删除具有复合键的实体

Question

我有 4 张桌子。

Country(id, name), CountryType(id, name), Client (id, name) 和Country_CountryType_Client 关系表（country_id、countryType_id、client_id）。

这是我的Country class：

@GeneratePojoBuilder(
        intoPackage = "*.builder")

@Entity
@Table(name = "MD_COUNTRY")   
@SequenceGenerator(
        name = "SEQ_MD_COUNTRY",
        sequenceName = "SEQ_MD_COUNTRY",
        allocationSize = 1)
public class Country implements Serializable {

    private static final long serialVersionUID = -3313476149373055743L;
    private Long md_country_id;
    private String nameKey;
    private List<CountryCountryTypeClient> cCTypeClients;

    @Id
    @GeneratedValue(
            generator = "SEQ_MD_COUNTRY")
    @Column(
            name = "MD_COUNTRY_ID")
    public Long getMd_country_id() {
        return md_country_id;
    }

    public void setMd_country_id(Long md_country_id) {
        this.md_country_id = md_country_id;
    }

    @Column(name = "MD_COUNTRY_NAME_KEY")
    public String getNameKey() {
        return this.nameKey;
    }

    public void setNameKey(String name) {
        this.nameKey = name;
    }


    @OneToMany(fetch=FetchType.EAGER,mappedBy="pk.country",cascade=CascadeType.ALL)
    public List<CountryCountryTypeClient> getCountryCountryTypeClient() {
        return cCTypeClients;
    }

    public void setCountryCountryTypes(List<CountryCountryTypeClient> countryCountryTypeClient) {
        this.cCTypeClient = countryCountryTypeClient;
    }
/* ... hashCode and equals methods..*/

CountryType 和 Client classes 看起来一样。

这是我的CountryCountryTypeClient 课程：

@GeneratePojoBuilder(
        intoPackage = "*.builder")
@Entity
@Table(
        name = "COUNTRY_COUNTRY_TYPE_CLIENT")
@AssociationOverrides({
    @AssociationOverride(name= "pk.country",
            joinColumns=@JoinColumn(name = "COUNTRY_ID")),
    @AssociationOverride(name="pk.countryType",
            joinColumns=@JoinColumn(name = "COUNTRY_TYPE_ID")),
    @AssociationOverride(name="pk.client",
            joinColumns=@JoinColumn(name = "CLIENT_ID"))
})
public class CountryCountryTypeClient implements Serializable{

    private static final long serialVersionUID = -879391903880384781L;

    private CountryCountryTypeClientPK pk = new CountryCountryTypeClientPK();

    public CountryCountryTypeClient() {}

    @EmbeddedId
    public CountryCountryTypeClientPK getPk() {
        return pk;
    }

    public void setPk(CountryCountryTypeClientPK pk) {
        this.pk = pk;
    }

    @Transient
    public Country getCountry(){
        return getPk().getCountry();
    }

    public void setCountry(Country country) {
        getPk().setCountry(country);
    }

    @Transient
    public CountryType getCountryType(){
        return getPk().getCountryType();
    }

    public void setCountryType(CountryType countryType) {
        getPk().setCountryType(countryType);
    }

    @Transient
    public Client getClient() {
        return getPk().getClient();
    }

    public void setClient(Client client) {
        getPk().setClient(client);
    }

/* ... hashCode and equals ... */

这是我的CountryCountryTypeClientPK 课程：

@Embeddable
public class CountryCountryTypeClientPK implements Serializable {

    private static final long serialVersionUID = -3934592006396010170L;

    private Country country;
    private CountryType countryType;
    private Client client;


    public CountryCountryTypeClientPK() {}

    @ManyToOne
    public Country getCountry() {
        return country;
    }
    public void setCountry(Country country) {
        this.country = country;
    }

    @ManyToOne
    public CountryType getCountryType() {
        return countryType;
    }
    public void setCountryType(CountryType countryType) {
        this.countryType = countryType;
    }

    @ManyToOne
    public Client getClient() {
        return client;
    }
    public void setClient(Client client) {
        this.client = client;
    }

/*... hashCode and equals methods ..*/

我的CountryCountryTypeClientRepository 班级：

public interface CountryCountryTypeRepository extends JpaRepository<CountryCountryTypeClient, CountryCountryTypeClientPK> {}

对于我的 Country 类，我有带有 saveCountry 方法的 CountryService 类：

public Country saveCountry(final Country dtoCountry) {
        //save NEW Country
        if(dtoCountry.getId()==null){
            de.bonprix.global.masterdata.model.Country modelWithoutID = convertToModel(dtoCountry);

            for (CountryCountryTypeClient cCTypeClient : modelWithoutID.getCountryCountryTypeClients()) {
            cCTypeClient.setCountry(modelWithoutID);
        }
        return convertToDTO(this.countryRepository.saveAndFlush(modelWithoutID));
        } 

        //save EDITED Country       
        else if (!(dtoCountry.getId()==null)){
            de.bonprix.global.masterdata.model.Country modelWithID = convertToModel(dtoCountry);

            for (CountryCountryTypeClient cCTypeClient : modelWithID.getCountryCountryTypeClients()) {
                cCTypeClient.setCountry(modelWithID); 
                ccTypeClientRepository.delete(cCTypeClient);
        }
            return convertToDTO(this.countryRepository.saveAndFlush(modelWithID));
        }
        return null;
    }

问题是：如何按 Country_ID 从我的 Country_CountryType_Client 表中删除所有行。不是按 PK，而是按 Country_ID。 当我在 Country Table 中保存国家时，Country_CountryType_Client 会自动更新为相应的值。

小例子，只是为了清除当前的问题。 现在在我的 Country_CountryType_Client 表中，我有了这个。

现在我想保存除了最后一行 (298-2-9) 之外具有所有相同关系的 NewCountry。我的 NewCountry 对（298-2-9 关系）一无所知。在保存之前，我必须删除所有具有 298 id 的行。

希望问题很清楚。

Answer 1

我真的不明白这个问题。似乎您真正想要做的就是从标识符为 298 的 Country 中删除单个 CountryCountryTypeClient。

因此，如果您要按照以下所述更新映射：

https://docs.oracle.com/cd/E19798-01/821-1841/giqxy/

 @OneToMany(fetch=FetchType.EAGER,mappedBy="pk.country",cascade=CascadeType.ALL, orphanRemoval = true)
    public List<CountryCountryTypeClient> getCountryCountryTypeClient() {
        return cCTypeClients;
    }

然后您可以简单地执行以下操作：

Country country = // the country with id 298
CountryCountryTypeClient client = // the client with id 298/2/9
country.getCountryCountryTypeClient().remove(client);
countryRepository.save(country);