传递给persist的实体是持久化的。这意味着，现在或以后在事务中，它将被写入数据库，并为该实体生成一...
传递给persist的实体是持久化的。这意味着，现在或以后在事务中，它将被写入数据库，并为该实体生成一...
I have a method that is supposed to delete an InventoryItem (i) in an array list (iList) when part of the description of that InventoryItem is entered. The method has to return the item that was delet... Sparx System Enterprise Architect Book ...
To avoid theNonUniqueObjectException, you need to use themergemethod offered by the JPAEntityManagerand inherited by the HibernateSessionas well. As explained inthis article, themergefetches a new entity snapshot from the database if there is no entity reference found in the Persistence Context,...
public JpaPersistEventListener(CallbackRegistry callbackRegistry) Method Detail injectCallbackRegistry public void injectCallbackRegistry(CallbackRegistry callbackRegistry) Description copied from interface: CallbackRegistryConsumer Injection of the Call...
We can think of this method as a universal tool for making an objectpersistentregardless of its state, whether it’stransientordetached. 3.6.Refresh Therefreshmethod appears in both the Hibernate API and JPA. As the name suggests, therefreshmethod is called to refresh an entity in thepersistent...
他教导说,默认情况下,jpa 在服务级别具有 @transactional,因此我们不需要在此处添加它。但在删除的情况下,我们实际上需要在使用entityManager.remove(object)时 (2认同) 小智 22 您需要将 @Transactional 添加到您的方法中 通过额外的支持信息可以改进您的答案。请[编辑]添加更多详细信息,例如引文或文档,以便其他...
The property set in persistence.xml or passed to createEntityManagerFactory affects all EntityManagers created by the factory. To apply the property to specific EntityManagers pass it to createEntityManager method.ExamplesExample 5-78 shows how to use this property in the persistence.xml file.Example...
we can choose a compact database representation and make sure that changing the enum in any way will not break the existing mapping. Therefore, we add theshortName, which will be used as the database representation, as an additional property to the Enum. We also need a method to get the...
to avoid this, we should be aware of the entity state and use the appropriate method for saving it. if we use the merge method, hibernate will re-attach the entity to the persistence context based on the @ id field : @test public void givendetachedpost_whentryingtomerge_thennoexceptionis...