我有一个实体类付款，其实体类 PaymentMethod 与多对一关系。
现在，因为我的PaymentMethod是主表。
所以我想保存付款而不影响主表PaymentMethod。
但每次我保存付款时，都会在PaymentMethod中插入新行。我无法弄清楚原因。
我正在使用SpringData save。
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 DATA
ID | NAME
1 | AA
2 | BB
3 | CC
付款后保存 具有重复名称的PAYMENT_METHOD条目？
我无法弄明白为什么？
为了保存，我为付款类型创建了简单的CRUDRepository
调用存储库的存储实体。
请建议我吵架的地方。
每当代码执行此行时：
paymentMethodRepository.findByName(payment.getPaymentMethod().getName());
它给出错误
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，我无法弄清楚代码是如何尝试刷新的。
我错过了什么吗？
问题解决了感谢@JB和@spiritwalker，但无法找到确切的根本原因，所以只讨论这个行为可能会在讨论中加上知识。
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
答案 0 :(得分：3)
首先删除级联，因为您在创建/修改付款时确实不想创建/修改PaymentMethod。
然后，当您创建付款时，为其分配您希望与之关联的现有PaymentMethod：
PaymentMethod existingPaymentMethod = em.find(PaymentMethod.class, idOfThePaymentMethod);
Payment payment = new Payment();
payment.setPaymentMethod(existingPaymentMethod);
em.persist(payment);
答案 1 :(得分：2)
从您的付款实体中删除 cascade = {CascadeType.REFRESH，CascadeType.MERGE，CascadeType.PERSIST} 。
由于PaymentMethod是您所说的主表，因此您不希望从Payment down到PaymentMethod发生任何级联操作。