title: How do i set the Transaction Isolation in EJB?
body: <p>I am not able to find a way to set TransactionIsolation in ejb. Can anybody tell me how do i set it? I am using persistence. </p>
  
  <p>I have looked the following classes :
  EntityManager , EntityManagerFactory, UserTransaction. None of them seems to have any method like setTransactionIsolation or such. Do we need to change persistence.xml?</p>
  
  <p>I just read a book named Mastering EJB 3.0 4th edition. They gave a full 10 page theory about Isolation level that this problems occur and that occurs and such things but at the end they gave this paragraph :-</p>
  
  <pre><code>"As we now know, the EJB standard does not deal with isolation levels directly,
  and rightly so. EJB is a component specification. It defines the behavior and
  contracts of a business component with clients and middleware infrastructure
  (containers) such that the component can be rendered as various middleware
  services properly. EJBs therefore are transactional components that interact
  with resource managers, such as the JDBC resource manager or JMS resource
  manager, via JTS, as part of a transaction. They are not, hence, resource
  components in themselves. Since isolation levels are very specific to the
  behavior and capabilities of the underlying resources, they should therefore be
  specified at the resource API levels. "
  </code></pre>
  
  <p>What exactly does it mean? What is meant by resource level APIs? Please help me. If persistence has no way to set Isolation Level then why do they give such huge theory in an EJB book and make it heavy in weight unnecessarily :(</p>