EntityManagerFactory not being injected using #PersistenceUnit - jpa-2.0

Question

I'm a java beginner. I'm in trouble to configure a persistance unit using JTA transactions.
I need to use a PostgreSQL database that is already defined, configured and populated. Using netbeans, i created the persistance.xml and glassfish-resources.xml as fallows:
<persistence version="2.0" xmlns="http://java.sun.com/xml/ns/persistence" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://java.sun.com/xml/ns/persistence http://java.sun.com/xml/ns/persistence/persistence_2_0.xsd">
<persistence-unit name="WellWatcherPU" transaction-type="JTA">
<jta-data-source>WellWatcherDB</jta-data-source>
<exclude-unlisted-classes>false</exclude-unlisted-classes>
<properties>
<property name="eclipselink.logging.logger" value="org.eclipse.persistence.logging.DefaultSessionLog"/>
<property name="eclipselink.logging.level" value="FINE"/>
</properties>
</persistence-unit>
</persistence>
and
<resources>
<jdbc-connection-pool allow-non-component-callers="false" associate-with-thread="false" connection-creation-retry-attempts="0" connection-creation-retry-interval-in-seconds="10" connection-leak-reclaim="false" connection-leak-timeout-in-seconds="0" connection-validation-method="auto-commit" datasource-classname="org.postgresql.ds.PGSimpleDataSource" fail-all-connections="false" idle-timeout-in-seconds="300" is-connection-validation-required="false" is-isolation-level-guaranteed="true" lazy-connection-association="false" lazy-connection-enlistment="false" match-connections="false" max-connection-usage-count="0" max-pool-size="32" max-wait-time-in-millis="60000" name="post-gre-sql_geowellex_geowellexPool" non-transactional-connections="false" pool-resize-quantity="2" res-type="javax.sql.DataSource" statement-timeout-in-seconds="-1" steady-pool-size="8" validate-atmost-once-period-in-seconds="0" wrap-jdbc-objects="false">
<property name="serverName" value="localhost"/>
<property name="portNumber" value="5432"/>
<property name="databaseName" value="DBNAME"/>
<property name="User" value="USER"/>
<property name="Password" value="PASSWORD"/>
<property name="URL" value="jdbc:postgresql://localhost:5432/DBNAME"/>
<property name="driverClass" value="org.postgresql.Driver"/>
</jdbc-connection-pool>
<jdbc-resource enabled="true" jndi-name="WellWatcherDB" object-type="user" pool-name="post-gre-sql_geowellex_geowellexPool"/>
</resources>
And this is how i get the EntityManagerFactory and EntityManager (as used in the netBeans example)
public class EUserDao {
#Resource
private UserTransaction utx = null;
#PersistenceUnit(unitName = "WellWatcherPU")
private EntityManagerFactory emf = null;
public EntityManager getEntityManager() {
return emf.createEntityManager(); <-------- NullPointerException here
}
public EUser getOne(long userId){
EntityManager em = getEntityManager();
try {
return em.find(EUser.class, userId);
} finally {
em.close();
}
}
EDIT:
And here is my glassfish deploy log:
Informações: [EL Config]: 2012-05-10 12:01:13.534--ServerSession(2017352940)--Connection(1901223982)--Thread(Thread[admin-thread-pool-4848(5),5,grizzly-kernel])--connecting(DatabaseLogin(
platform=>DatabasePlatform
user name=> ""
connector=>JNDIConnector datasource name=>null
))
Informações: [EL Config]: 2012-05-10 12:01:13.534--ServerSession(2017352940)--Connection(1462281761)--Thread(Thread[admin-thread-pool-4848(5),5,grizzly-kernel])--Connected: jdbc:postgresql://localhost:5432/geowellex?loginTimeout=0&prepareThreshold=0
User: geowellex
Database: PostgreSQL Version: 9.1.3
Driver: PostgreSQL Native Driver Version: PostgreSQL 8.3 JDBC3 with SSL (build 603)
Informações: [EL Config]: 2012-05-10 12:01:13.534--ServerSession(2017352940)--Connection(766700859)--Thread(Thread[admin-thread-pool-4848(5),5,grizzly-kernel])--connecting(DatabaseLogin(
platform=>PostgreSQLPlatform
user name=> ""
connector=>JNDIConnector datasource name=>null
))
What's wrong?

Answer 1

Most likely problem is that your EUserDao is just regular class. Injection works only for container managed classes. Annotations like #PersistenceUnit and #Resource are not processed for normal classes.
Following types of classes are container managed classes (and in those #PersistenceUnit can be used):
Servlet: servlets, servlet filters, event listeners
JSP: tag handlers, tag library event listeners
JSF: scoped managed beans
JAX-WS: service endpoints, handlers
EJB: beans, interceptors
Managed Beans: managed beans
CDI: CDI-style managed beans, decorators
Java EE Platform: main class (static), login callback handler

Answer 2

I see that in your code declare:
private EntityManagerFactory emf = null;
but never create one... like this
emf = Persistence.createEntityManagerFactory("WellWatcherPU");
Thats why you get a Null Pointer Exception when use the object!
public EntityManager getEntityManager() {
return emf.createEntityManager(); <-------- NullPointerException here
}