交易后休眠自动保存

Question

This is my hibernate relationship

@OneToMany(cascade = {CascadeType.ALL})
@JoinColumn(name = "b_id", nullable = false)
@XmlElement
@JsonIgnore
@Getter
@Setter
private List<A> aList = new ArrayList<>();



@ManyToOne
@JoinColumn(name = "b_id", nullable = false, insertable = false, updatable = false)
@XmlTransient
@Getter
@Setter
private B b;

So would be like I call method x, there I´m get from database entity B then I set new aList with all A with id null, into B and then I return B in the method but I´m not saving B in any moment. When I see the value of the aList inside B this A of the aList already have ids!!!, so in some point the B is save in database and aList is done on cascade. The thing is that I´m calling this method inside @Service class from my Controller, so I´m thinking that because the transaction is finish, Hibernate detect a change into the B and decide to persist the changes. The question would be, how avoid that behavior!!!

Answer 1

Object in session cache will be synchronized with database on Session.flush() , including relations as you are using CascadeType.ALL .

If you want to avoid the synchronization on some object, you can use the Session.evict(someObject) method before the transaction commit.

Answer 2

我找到了解决方案，忘了说我在使用Spring，所以最后我将@Transactional（readOnly = true）添加到我的方法中，而不是在服务类级别。