获取特定列表后，Spring Jpa 删除操作不起作用

Question

这些是我的实体；

@Entity

 public class IpAddress{

    @Id

    @Column(nullable = false, updatable = false)

    @GeneratedValue(strategy = GenerationType.SEQUENCE, generator = "SEQ")

    @Getter

    private Long id;

     @ManyToOne(fetch = FetchType.LAZY)

     private final Application application;

     .....

 }

@Entity

public class Application{

@Column(nullable = false, updatable = false)

private final String applicationId;

@OneToMany(mappedBy = "application", cascade = CascadeType.ALL, orphanRemoval = true)

private List<IpAddress> ipAddresses = new ArrayList<>();

}

@Entity

public class MerchantApplication {

    @Id

    @Column(nullable = false, updatable = false)

    @GeneratedValue(strategy = GenerationType.SEQUENCE, generator = "SEQ")

    @Getter

    private Long id;

    @OneToOne

    private final Merchant merchant;

    @OneToOne(cascade = CascadeType.ALL)

    private final Application application;

    @ManyToOne(fetch = FetchType.LAZY)

    private final User user;

}

这是我尝试删除的服务方法：

@Transactional

    public void deleteIpAddressForMerchant(Long merchantId,Long ipAddressId) {

        Merchant merchant = merchantRepository.getMerchant(merchantId);

        MerchantApplication merchantApplication = merchant.getMerchantApplication();

        if (Objects.isNull(merchantApplication))

            throw new ApplicationNotFoundException();

        if (merchantApplication.getApplication().getIpAddresses().size() == 1) {

            throw new IpAddressCannotBeDeleted();

        }

        IpAddress ipAddress = ipAddressRepository.getByIdAndApplication(ipAddressId, merchantApplication.getApplication());

        ipAddressRepository.delete(ipAddress);

    }

当我在服务方法中删除此块时，它工作正常；

if (merchantApplication.getApplication().getIpAddresses().size() == 1) {

            throw new IpAddressCannotBeDeleted();

        }

但是这样不行。你能帮我吗，有什么问题吗？

Answer 1

如果您获取一个orphanRemoval = true在@Transactional方法中具有属性的实体字段，它会在该方法返回时保存该字段以及您所做的更改。在你的情况下，你取merchantApplication.getApplication().getIpAddresses()但是您没有对其进行任何更改，然后将获取的列表按原样保存。您可以删除获取列表中要删除的元素。

Answer 2

您以编程方式在以下代码中抛出异常：&nbsp;if (merchantApplication.getApplication().getIpAddresses().size() == 1)&nbsp;&nbsp;{&nbsp; &nbsp; &nbsp;throw new IpAddressCannotBeDeleted();&nbsp;}默认情况下，如果在未处理的方法中发生运行时异常（try...catch），事务将回滚。你的IpAddressCannotBeDeleted班级有延伸RuntimeException吗？如果是这样，请尝试将以下属性添加到您的@Transactional注释中：&nbsp;@Transactional(noRollbackFor={IpAddressCannotBeDeleted.class, ApplicationNotFoundException.class})如果在您的方法实现中抛出了这两种类型的异常，则 `noRollbackFor' 属性可防止 Spring 回滚事务。