我有一个实体类 付款 其中有实体类 付款方式 与 多对一 关系。
现在因为我的 PaymentMethod 是主表。
所以我想在不影响主表 PaymentMethod 的情况下保存付款。
但是每次我保存付款时，它都会在 PaymentMethod 中插入新行。我无法弄清楚为什么。
我正在使用 SpringData 保存。
Payment.java
@Entity
@Table(name="payment")
public class Payment implements Serializable {
@Id
@GeneratedValue(strategy = GenerationType.AUTO)
private Long id;
@ManyToOne(cascade={CascadeType.REFRESH,CascadeType.MERGE,CascadeType.PERSIST})
@JoinColumn(name="payment_method_id")
private PaymentMethod paymentMethod;
//getter and setters
}
PaymentMethod.java
@Table(name="paymentmethod")
public class PaymentMethod implements Serializable {
@Id
@GeneratedValue(strategy = GenerationType.AUTO)
private Long id;
@Column(name="name",unique=true ,nullable=false)
private String name;
//GETTER AND SETTERS
}
PAYMENT_METHOD 数据
ID | NAME
1 | AA
2 | BB
3 | CC
付款后保存
具有重复名称的 PAYMENT_METHOD 条目？
我无法弄清楚为什么？
为了保存，我为 Payment 类型创建了简单的 CRUDRepository
调用存储库的保存实体。
请建议我在哪里摔倒。
每当代码执行此行时:
paymentMethodRepository.findByName(payment.getPaymentMethod().getName());
它给出了错误
Caused by: org.hibernate.TransientPropertyValueException: object references an unsaved transient instance - save the transient instance before flushing: com.enrollment.domain.Payment.paymentMethod -> com.enrollment.domain.PaymentMethod
at org.hibernate.engine.spi.CascadingAction$8.noCascade(CascadingAction.java:380)
at org.hibernate.engine.internal.Cascade.cascade(Cascade.java:176)
at org.hibernate.event.internal.AbstractSaveEventListener.cascadeBeforeSave(AbstractSaveEventListener.java:423)
at org.hibernate.event.internal.AbstractSaveEventListener.performSaveOrReplicate(AbstractSaveEventListener.java:264)
at org.hibernate.event.internal.AbstractSaveEventListener.performSave(AbstractSaveEventListener.java:193)
at org.hibernate.event.internal.AbstractSaveEventListener.saveWithGeneratedId(AbstractSaveEventListener.java:136)
at org.hibernate.ejb.event.EJB3PersistEventListener.saveWithGeneratedId(EJB3PersistEventListener.java:78)
at org.hibernate.event.internal.DefaultPersistEventListener.entityIsTransient(DefaultPersistEventListener.java:208)
at org.hibernate.event.internal.DefaultPersistEventListener.onPersist(DefaultPersistEventListener.java:151)
at org.hibernate.internal.SessionImpl.firePersistOnFlush(SessionImpl.java:870)
at org.hibernate.internal.SessionImpl.persistOnFlush(SessionImpl.java:863)
at org.hibernate.engine.spi.CascadingAction$8.cascade(CascadingAction.java:346)
at org.hibernate.engine.internal.Cascade.cascadeToOne(Cascade.java:380)
at org.hibernate.engine.internal.Cascade.cascadeAssociation(Cascade.java:323)
at org.hibernate.engine.internal.Cascade.cascadeProperty(Cascade.java:208)
at org.hibernate.engine.internal.Cascade.cascadeCollectionElements(Cascade.java:409)
at org.hibernate.engine.internal.Cascade.cascadeCollection(Cascade.java:350)
at org.hibernate.engine.internal.Cascade.cascadeAssociation(Cascade.java:326)
at org.hibernate.engine.internal.Cascade.cascadeProperty(Cascade.java:208)
at org.hibernate.engine.internal.Cascade.cascade(Cascade.java:165)
at org.hibernate.event.internal.AbstractSaveEventListener.cascadeAfterSave(AbstractSaveEventListener.java:448)
at org.hibernate.event.internal.AbstractSaveEventListener.performSaveOrReplicate(AbstractSaveEventListener.java:293)
at org.hibernate.event.internal.AbstractSaveEventListener.performSave(AbstractSaveEventListener.java:193)
at org.hibernate.event.internal.AbstractSaveEventListener.saveWithGeneratedId(AbstractSaveEventListener.java:136)
at org.hibernate.ejb.event.EJB3PersistEventListener.saveWithGeneratedId(EJB3PersistEventListener.java:78)
at org.hibernate.event.internal.DefaultPersistEventListener.entityIsTransient(DefaultPersistEventListener.java:208)
at org.hibernate.event.internal.DefaultPersistEventListener.onPersist(DefaultPersistEventListener.java:151)
at org.hibernate.internal.SessionImpl.firePersistOnFlush(SessionImpl.java:870)
at org.hibernate.internal.SessionImpl.persistOnFlush(SessionImpl.java:863)
at org.hibernate.engine.spi.CascadingAction$8.cascade(CascadingAction.java:346)
at org.hibernate.engine.internal.Cascade.cascadeToOne(Cascade.java:380)
at org.hibernate.engine.internal.Cascade.cascadeAssociation(Cascade.java:323)
at org.hibernate.engine.internal.Cascade.cascadeProperty(Cascade.java:208)
at org.hibernate.engine.internal.Cascade.cascade(Cascade.java:165)
at org.hibernate.event.internal.AbstractSaveEventListener.cascadeAfterSave(AbstractSaveEventListener.java:448)
at org.hibernate.event.internal.AbstractSaveEventListener.performSaveOrReplicate(AbstractSaveEventListener.java:293)
at org.hibernate.event.internal.AbstractSaveEventListener.performSave(AbstractSaveEventListener.java:193)
at org.hibernate.event.internal.AbstractSaveEventListener.saveWithGeneratedId(AbstractSaveEventListener.java:136)
at org.hibernate.ejb.event.EJB3PersistEventListener.saveWithGeneratedId(EJB3PersistEventListener.java:78)
at org.hibernate.event.internal.DefaultPersistEventListener.entityIsTransient(DefaultPersistEventListener.java:208)
at org.hibernate.event.internal.DefaultPersistEventListener.onPersist(DefaultPersistEventListener.java:151)
at org.hibernate.internal.SessionImpl.firePersistOnFlush(SessionImpl.java:870)
at org.hibernate.internal.SessionImpl.persistOnFlush(SessionImpl.java:863)
at org.hibernate.engine.spi.CascadingAction$8.cascade(CascadingAction.java:346)
at org.hibernate.engine.internal.Cascade.cascadeToOne(Cascade.java:380)
at org.hibernate.engine.internal.Cascade.cascadeAssociation(Cascade.java:323)
at org.hibernate.engine.internal.Cascade.cascadeProperty(Cascade.java:208)
at org.hibernate.engine.internal.Cascade.cascade(Cascade.java:165)
at org.hibernate.event.internal.AbstractSaveEventListener.cascadeBeforeSave(AbstractSaveEventListener.java:423)
at org.hibernate.event.internal.AbstractSaveEventListener.performSaveOrReplicate(AbstractSaveEventListener.java:264)
at org.hibernate.event.internal.AbstractSaveEventListener.performSave(AbstractSaveEventListener.java:193)
at org.hibernate.event.internal.AbstractSaveEventListener.saveWithGeneratedId(AbstractSaveEventListener.java:136)
at org.hibernate.ejb.event.EJB3PersistEventListener.saveWithGeneratedId(EJB3PersistEventListener.java:78)
at org.hibernate.event.internal.DefaultPersistEventListener.entityIsTransient(DefaultPersistEventListener.java:208)
at org.hibernate.event.internal.DefaultPersistEventListener.onPersist(DefaultPersistEventListener.java:151)
at org.hibernate.internal.SessionImpl.firePersistOnFlush(SessionImpl.java:870)
at org.hibernate.internal.SessionImpl.persistOnFlush(SessionImpl.java:863)
at org.hibernate.engine.spi.CascadingAction$8.cascade(CascadingAction.java:346)
at org.hibernate.engine.internal.Cascade.cascadeToOne(Cascade.java:380)
at org.hibernate.engine.internal.Cascade.cascadeAssociation(Cascade.java:323)
at org.hibernate.engine.internal.Cascade.cascadeProperty(Cascade.java:208)
at org.hibernate.engine.internal.Cascade.cascade(Cascade.java:165)
at org.hibernate.event.internal.AbstractSaveEventListener.cascadeBeforeSave(AbstractSaveEventListener.java:423)
at org.hibernate.event.internal.AbstractSaveEventListener.performSaveOrReplicate(AbstractSaveEventListener.java:264)
at org.hibernate.event.internal.AbstractSaveEventListener.performSave(AbstractSaveEventListener.java:193)
at org.hibernate.event.internal.AbstractSaveEventListener.saveWithGeneratedId(AbstractSaveEventListener.java:136)
at org.hibernate.ejb.event.EJB3PersistEventListener.saveWithGeneratedId(EJB3PersistEventListener.java:78)
at org.hibernate.event.internal.DefaultPersistEventListener.entityIsTransient(DefaultPersistEventListener.java:208)
at org.hibernate.event.internal.DefaultPersistEventListener.onPersist(DefaultPersistEventListener.java:151)
at org.hibernate.internal.SessionImpl.firePersistOnFlush(SessionImpl.java:870)
at org.hibernate.internal.SessionImpl.persistOnFlush(SessionImpl.java:863)
at org.hibernate.engine.spi.CascadingAction$8.cascade(CascadingAction.java:346)
at org.hibernate.engine.internal.Cascade.cascadeToOne(Cascade.java:380)
at org.hibernate.engine.internal.Cascade.cascadeAssociation(Cascade.java:323)
at org.hibernate.engine.internal.Cascade.cascadeProperty(Cascade.java:208)
at org.hibernate.engine.internal.Cascade.cascadeCollectionElements(Cascade.java:409)
at org.hibernate.engine.internal.Cascade.cascadeCollection(Cascade.java:350)
at org.hibernate.engine.internal.Cascade.cascadeAssociation(Cascade.java:326)
at org.hibernate.engine.internal.Cascade.cascadeProperty(Cascade.java:208)
at org.hibernate.engine.internal.Cascade.cascade(Cascade.java:165)
at org.hibernate.event.internal.AbstractFlushingEventListener.cascadeOnFlush(AbstractFlushingEventListener.java:160)
at org.hibernate.event.internal.AbstractFlushingEventListener.prepareEntityFlushes(AbstractFlushingEventListener.java:151)
at org.hibernate.event.internal.AbstractFlushingEventListener.flushEverythingToExecutions(AbstractFlushingEventListener.java:88)
at org.hibernate.event.internal.DefaultAutoFlushEventListener.onAutoFlush(DefaultAutoFlushEventListener.java:58)
at org.hibernate.internal.SessionImpl.autoFlushIfRequired(SessionImpl.java:1186)
at org.hibernate.internal.SessionImpl.list(SessionImpl.java:1241)
at org.hibernate.internal.QueryImpl.list(QueryImpl.java:101)
at org.hibernate.ejb.QueryImpl.getSingleResult(QueryImpl.java:285)
当我从存储库调用 finder 方法时，如果尝试刷新它，我无法弄清楚代码如何。
我错过了什么吗？
感谢@JB 和@spiritwalker 解决了问题，但无法找到确切的根本原因，因此仅讨论行为可能会增加太多知识。
Behaviour ..
Open Transaction
1. validate
2. save child
3. validate and update
4. save parent
Close Transaction
it was giving above error.
Now, after code change it worked
Open Transaction
1. validate
2. validate and update
3. save child
4. save parent
Close Transaction
最佳答案
首先删除级联，因为您在创建/修改 Payment 时确实不想创建/修改 PaymentMethod。
然后，当您创建 Payment 时，将您希望它关联的现有 PaymentMethod 分配给它:
PaymentMethod existingPaymentMethod = em.find(PaymentMethod.class, idOfThePaymentMethod);
Payment payment = new Payment();
payment.setPaymentMethod(existingPaymentMethod);
em.persist(payment);
关于hibernate - @ManyToOne 单向映射，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/14919726/