James Wong [https://community.jboss.org/people/jwong22] created the discussion "@PersistenceUnit don't return entityManager" To view the discussion, visit: https://community.jboss.org/message/800638#800638 -------------------------------------------------------------- Hello    I have a problem with the annotation @PersistenceUnit.    I use it to define my EntityManager but it always return null. I use the server JBOSS 7.1 This is my persistence.xml <?xml version="1.0" encoding="UTF-8"?> <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="eiad-ejbPU" transaction-type="JTA">     <provider>org.hibernate.ejb.HibernatePersistence</provider>     <jta-data-source>java:jboss/datasources/EiadDS</jta-data-source>     <class>fr.eiad.business.Temps</class>     <exclude-unlisted-classes>false</exclude-unlisted-classes>     <properties>       <property name="hibernate.show_sql" value="true" />       <property name="hibernate.format_sql" value="true" />       <property name="hibernate.dialect" value="org.hibernate.dialect.MySQLInnoDBDialect" />     </properties>   </persistence-unit> </persistence> and this is my Service.java   @javax.persistence.PersistenceContext(unitName = "eiad-ejbPU")   private EntityManager    entityManager;   private static final Log log = LogFactory.getLog(TempsService.class);     public void persist(final Temps temps)   {     log.debug("persisting Temps instance"); //$NON-NLS-1$     entityManager.persist(temps);   }     public final Temps findById(final Integer id)   {     log.debug("getting User instance with id: " + id);     try     {       final Temps instance = entityManager.find(Temps.class, id);       log.debug("get successful");       return instance;     }     catch (final RuntimeException re)     {       log.error("get failed", re);       throw re;     }   } Thanks -------------------------------------------------------------- Reply to this message by going to Community [https://community.jboss.org/message/800638#800638] Start a new discussion in Datasource Configuration at Community [https://community.jboss.org/choose-container!input.jspa?contentType=1&...]