0
類
的實例，我有一個非常簡單的實體：休眠 - 對象不聲明
import javax.persistence.*;
@Entity(name = "Message")
public class MessageEntity {
private Long id;
@Id
@GeneratedValue(strategy = GenerationType.IDENTITY)
public Long getId() {
return this.id;
}
public void setId(Long id) {
this.id = id;
}
}
的的persistence.xml包含hibernate.hbm2ddl.auto=create-drop，所以表中創建的基礎上正確的註釋。不過，當我堅持的實體，我得到以下異常：
org.hibernate.PropertyAccessException: IllegalArgumentException occurred calling getter of org.acme.project.MessageEntity.id
at org.hibernate.property.BasicPropertyAccessor$BasicGetter.get(BasicPropertyAccessor.java:192) [hibernate-core-4.3.7.Final.jar:4.3.7.Final]
at org.hibernate.tuple.entity.AbstractEntityTuplizer.getIdentifier(AbstractEntityTuplizer.java:346) [hibernate-core-4.3.7.Final.jar:4.3.7.Final]
at org.hibernate.persister.entity.AbstractEntityPersister.getIdentifier(AbstractEntityPersister.java:4746) [hibernate-core-4.3.7.Final.jar:4.3.7.Final]
at org.hibernate.persister.entity.AbstractEntityPersister.isTransient(AbstractEntityPersister.java:4465) [hibernate-core-4.3.7.Final.jar:4.3.7.Final]
at org.hibernate.engine.internal.ForeignKeys.isTransient(ForeignKeys.java:243) [hibernate-core-4.3.7.Final.jar:4.3.7.Final]
at org.hibernate.event.internal.AbstractSaveEventListener.getEntityState(AbstractSaveEventListener.java:511) [hibernate-core-4.3.7.Final.jar:4.3.7.Final]
at org.hibernate.event.internal.DefaultPersistEventListener.onPersist(DefaultPersistEventListener.java:116) [hibernate-core-4.3.7.Final.jar:4.3.7.Final]
at org.hibernate.event.internal.DefaultPersistEventListener.onPersist(DefaultPersistEventListener.java:75) [hibernate-core-4.3.7.Final.jar:4.3.7.Final]
at org.hibernate.internal.SessionImpl.firePersist(SessionImpl.java:811) [hibernate-core-4.3.7.Final.jar:4.3.7.Final]
at org.hibernate.internal.SessionImpl.persist(SessionImpl.java:784) [hibernate-core-4.3.7.Final.jar:4.3.7.Final]
at org.hibernate.internal.SessionImpl.persist(SessionImpl.java:789) [hibernate-core-4.3.7.Final.jar:4.3.7.Final]
at org.hibernate.jpa.spi.AbstractEntityManagerImpl.persist(AbstractEntityManagerImpl.java:1181) [hibernate-entitymanager-4.3.7.Final.jar:4.3.7.Final]
... 154 more
Caused by: java.lang.IllegalArgumentException: object is not an instance of declaring class
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) [rt.jar:1.8.0_20]
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62) [rt.jar:1.8.0_20]
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) [rt.jar:1.8.0_20]
at java.lang.reflect.Method.invoke(Method.java:483) [rt.jar:1.8.0_20]
at org.hibernate.property.BasicPropertyAccessor$BasicGetter.get(BasicPropertyAccessor.java:169) [hibernate-core-4.3.7.Final.jar:4.3.7.Final]
... 165 more
或者當字段註釋，而不是吸氣：
org.hibernate.PropertyAccessException: could not get a field value by reflection getter of org.acme.project.MessageEntity.id
at org.hibernate.property.DirectPropertyAccessor$DirectGetter.get(DirectPropertyAccessor.java:60) [hibernate-core-4.3.7.Final.jar:4.3.7.Final]
at org.hibernate.tuple.entity.AbstractEntityTuplizer.getIdentifier(AbstractEntityTuplizer.java:346) [hibernate-core-4.3.7.Final.jar:4.3.7.Final]
at org.hibernate.persister.entity.AbstractEntityPersister.getIdentifier(AbstractEntityPersister.java:4746) [hibernate-core-4.3.7.Final.jar:4.3.7.Final]
at org.hibernate.persister.entity.AbstractEntityPersister.isTransient(AbstractEntityPersister.java:4465) [hibernate-core-4.3.7.Final.jar:4.3.7.Final]
at org.hibernate.engine.internal.ForeignKeys.isTransient(ForeignKeys.java:243) [hibernate-core-4.3.7.Final.jar:4.3.7.Final]
at org.hibernate.event.internal.AbstractSaveEventListener.getEntityState(AbstractSaveEventListener.java:511) [hibernate-core-4.3.7.Final.jar:4.3.7.Final]
at org.hibernate.event.internal.DefaultPersistEventListener.onPersist(DefaultPersistEventListener.java:116) [hibernate-core-4.3.7.Final.jar:4.3.7.Final]
at org.hibernate.event.internal.DefaultPersistEventListener.onPersist(DefaultPersistEventListener.java:75) [hibernate-core-4.3.7.Final.jar:4.3.7.Final]
at org.hibernate.internal.SessionImpl.firePersist(SessionImpl.java:811) [hibernate-core-4.3.7.Final.jar:4.3.7.Final]
at org.hibernate.internal.SessionImpl.persist(SessionImpl.java:784) [hibernate-core-4.3.7.Final.jar:4.3.7.Final]
at org.hibernate.internal.SessionImpl.persist(SessionImpl.java:789) [hibernate-core-4.3.7.Final.jar:4.3.7.Final]
at org.hibernate.jpa.spi.AbstractEntityManagerImpl.persist(AbstractEntityManagerImpl.java:1181) [hibernate-entitymanager-4.3.7.Final.jar:4.3.7.Final]
... 154 more
Caused by: java.lang.IllegalArgumentException: Can not set java.lang.Long field org.acme.project.MessageEntity.id to org.acme.project.MessageEntity
at sun.reflect.UnsafeFieldAccessorImpl.throwSetIllegalArgumentException(UnsafeFieldAccessorImpl.java:167) [rt.jar:1.8.0_20]
at sun.reflect.UnsafeFieldAccessorImpl.throwSetIllegalArgumentException(UnsafeFieldAccessorImpl.java:171) [rt.jar:1.8.0_20]
at sun.reflect.UnsafeFieldAccessorImpl.ensureObj(UnsafeFieldAccessorImpl.java:58) [rt.jar:1.8.0_20]
at sun.reflect.UnsafeObjectFieldAccessorImpl.get(UnsafeObjectFieldAccessorImpl.java:36) [rt.jar:1.8.0_20]
at java.lang.reflect.Field.get(Field.java:387) [rt.jar:1.8.0_20]
at org.hibernate.property.DirectPropertyAccessor$DirectGetter.get(DirectPropertyAccessor.java:57) [hibernate-core-4.3.7.Final.jar:4.3.7.Final]
... 165 more
產生異常的代碼是非常複雜的，所以採取了此刻真正得到它：
@PersistenceContext
private EntityManager em;
public void doMagic() {
this.em.persist(new MessageEntity());
}
這可能是一個小的，非常愚蠢的錯誤，使休眠認爲它應該的ID設置爲MessageEntity，但我看不到找到它在哪裏。有什麼問題？
向我們展示實體的完整代碼以及引發該異常的代碼。 –
@JBNizet我添加了getter和setter。 –
您完全更改了代碼，其中包含其他幾個字段，關於構建器模式的註釋以及SequenceGenerator。你是否仍然獲得與上述實體相同的異常，包含單個id字段和身份生成器？ –