public PersistenceManager getPersistenceManager ();
public PersistenceManager getPersistenceManager (String user, String pass);

The PersistenceManagerFactory interface includes two getPersistenceManager methods for obtaining PersistenceManager instances. One version takes as parameters the user name and password to use for the PersistenceManager's data store connection(s). The other version relies on the ConnectionUserName and ConnectionPassword settings of the PersistenceManagerFactory. Both methods may return a newly-constructed PersistenceManager, or may return one from a pool of instances.

After the first PersistenceManager is acquired from a PersistenceManagerFactory, the factory's configuration is "frozen". Any attempt to change its properties will result in a JDOUserException.