Hibernate Set 映射时出现下列异常，求解

Question

ERROR: HHH000122: IllegalArgumentException in class: Entity.OrderItem, getter method of property: orderItemId
Exception in thread "main" org.hibernate.PropertyAccessException: IllegalArgumentException occurred calling getter of Entity.OrderItem.orderItemId
at org.hibernate.property.access.spi.GetterMethodImpl.get(GetterMethodImpl.java:64)
at org.hibernate.tuple.entity.AbstractEntityTuplizer.getIdentifier(AbstractEntityTuplizer.java:230)
at org.hibernate.persister.entity.AbstractEntityPersister.getIdentifier(AbstractEntityPersister.java:4725)
at org.hibernate.persister.entity.AbstractEntityPersister.isTransient(AbstractEntityPersister.java:4425)
at org.hibernate.engine.internal.ForeignKeys.isTransient(ForeignKeys.java:226)
at org.hibernate.event.internal.AbstractSaveEventListener.getEntityState(AbstractSaveEventListener.java:499)
at org.hibernate.event.internal.DefaultSaveOrUpdateEventListener.performSaveOrUpdate(DefaultSaveOrUpdateEventListener.java:83)
at org.hibernate.event.internal.DefaultSaveOrUpdateEventListener.onSaveOrUpdate(DefaultSaveOrUpdateEventListener.java:73)
at org.hibernate.internal.SessionImpl.fireSaveOrUpdate(SessionImpl.java:658)
at org.hibernate.internal.SessionImpl.saveOrUpdate(SessionImpl.java:650)
at org.hibernate.engine.spi.CascadingActions$5.cascade(CascadingActions.java:219)
at org.hibernate.engine.internal.Cascade.cascadeToOne(Cascade.java:458)
at org.hibernate.engine.internal.Cascade.cascadeAssociation(Cascade.java:383)
at org.hibernate.engine.internal.Cascade.cascadeProperty(Cascade.java:193)
at org.hibernate.engine.internal.Cascade.cascadeCollectionElements(Cascade.java:491)
at org.hibernate.engine.internal.Cascade.cascadeCollection(Cascade.java:423)
at org.hibernate.engine.internal.Cascade.cascadeAssociation(Cascade.java:386)
at org.hibernate.engine.internal.Cascade.cascadeProperty(Cascade.java:193)
at org.hibernate.engine.internal.Cascade.cascade(Cascade.java:126)
at org.hibernate.event.internal.AbstractSaveEventListener.cascadeAfterSave(AbstractSaveEventListener.java:445)
at org.hibernate.event.internal.AbstractSaveEventListener.performSaveOrReplicate(AbstractSaveEventListener.java:281)
at org.hibernate.event.internal.AbstractSaveEventListener.performSave(AbstractSaveEventListener.java:182)
at org.hibernate.event.internal.AbstractSaveEventListener.saveWithGeneratedId(AbstractSaveEventListener.java:125)
at org.hibernate.event.internal.DefaultSaveOrUpdateEventListener.saveWithGeneratedOrRequestedId(DefaultSaveOrUpdateEventListener.java:192)
at org.hibernate.event.internal.DefaultSaveEventListener.saveWithGeneratedOrRequestedId(DefaultSaveEventListener.java:38)
at org.hibernate.event.internal.DefaultSaveOrUpdateEventListener.entityIsTransient(DefaultSaveOrUpdateEventListener.java:177)
at org.hibernate.event.internal.DefaultSaveEventListener.performSaveOrUpdate(DefaultSaveEventListener.java:32)
at org.hibernate.event.internal.DefaultSaveOrUpdateEventListener.onSaveOrUpdate(DefaultSaveOrUpdateEventListener.java:73)
at org.hibernate.internal.SessionImpl.fireSave(SessionImpl.java:689)
at org.hibernate.internal.SessionImpl.save(SessionImpl.java:681)
at org.hibernate.internal.SessionImpl.save(SessionImpl.java:676)
at Handler.OrderHandler.addOrder(OrderHandler.java:26)
at MyTester.main(MyTester.java:32)
Caused by: java.lang.IllegalArgumentException: object is not an instance of declaring class
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:498)
at org.hibernate.property.access.spi.GetterMethodImpl.get(GetterMethodImpl.java:41)
... 32 more

Answer 1

OrderItem.orderItemId实体类里面的这个属性的get方法有问题吗？你看看