在我的情况下，提交JPA事务的最佳方法是什么？

Question

Assume I have 3 Entity Model:

History.class
DetilHistory.class
Logs.class

I have to write my code like this:

//Create History
History h = new History(new Date(), 1, 1, 1);
h.save();

//Create Detil History
DetilHistory dh = new DetilHistory(1, 1, 1, h.id);
dh.save();

//Create Logs
Logs l = new Logs(1,1,1,dh.id);
l.save();

I have to get h.id first for dh.referecendIdOfHistory. AND I have to get dh.id first for l.referecendIdOfDetilHistory.

BUT, Sometimes i have to change the variable h or dh below that code like this:

h.closeDate= new Date();
h.value = 2;
h.save();

I do it for Detil History too.

Unfortunately JPA can't do it like that. I know the reason why JPA don't allow that.

I have issues about:

• detached entity passed to persist
• JPA has not been initialized
• etc

I have solved them with:

- JPAPluginStartTx(rollback)
- JPA.em().flush(); JPA.em().getTransaction().commit();

Somebody please could tell me how the best way to do it?

Answer 1

What do your save() methods do? Maybe you could try getting an EntityManager instance, opening a transaction with em.getTransaction().begin, then persisting all the entities in order, then committing the transaction.