Entity Manager Type and Associate Transaction

0
votes

AFAIK, there are two types of entity manager. 1. Container managed entity manager 2. Application managed entity manager

  1. Container managed entity manager
    • This type of em uses JTA transaction only

Below is my code: 

@PersistenceContext(unitName = "", type = Transaction)
EntityManager em;


public void persist(T entity) {
em.persist(entity)
}

Questions: There is exception throw when execute the code : TransactionRequireException Why there is this kind of exception? There is no TransactionRequireException happen after added @Resource UserTransaction to the method persist(). I wonder UserTransaction is belongs to JTA right. 

EntityTransaction et = em.getTransaction();

Refer to the above code, Why JTA transaction type cannot invokes getTransaction() ?

Can extended JTA Transaction em use outside of EJB?

  1. Application managed entity manager
    • Utilize JTA Transaction
    • Utilize JDBC Transaction(Resource Local Transaction)

Please anyone provide example of source code on JDBC Transaction type.

1
jpatransactionsentitymanager

1 Answers

2
votes

A JPA persistence unit can either be JTA or RESOURCE_LOCAL.

If you use JTA, then you must use JTA for transaction, either through SessionBeans or by accessing JTA directly.

See, http://en.wikibooks.org/wiki/Java_Persistence/Runtime#Java_Enterprise_Edition