Inject EntityManager in JSF managed bean always NULL
jochen.seifarth Feb 27, 2006 6:56 PMTrying to inject an EntityManager into a JSF managed bean fails in JBoss 4.0.4RC1.
My entities are in a JAR, JSF managed beans in a WAR (beans are listed as managed bean in faces-config.xml and work....apart from an injected EntityManager always being NULL). Both the JAR and the WAR are bundled in an EAR which is then deployed.
META-INF/persistence.xml in entities JAR is
<persistence> <persistence-unit name="jsEntities"> <provider>org.hibernate.ejb.HibernatePersistence</provider> <jta-data-source>java:/bookingDatasource</jta-data-source> <properties> <property name="hibernate.dialect" value="org.hibernate.dialect.MySQLDialect"/> <property name="hibernate.transaction.manager_lookup_class" value="org.hibernate.transaction.JBossTransactionManagerLookup"/> <property name="hibernate.transaction.flush_before_completion" value="true"/> <property name="hibernate.hbm2ddl.auto" value="update"/> <property name="hibernate.show_sql" value="true"/> </properties> </persistence-unit> </persistence>
The JSF managed beans looks like this:
import javax.annotation.Resource; import javax.persistence.*; import java.util.*; public class AddressPage { @PersistenceContext(unitName="jsEntities") private EntityManager em; @Resource private UserTransaction utx; public Person person = new Person(); public void findPerson() { if (em == null) System.out.println(">>>em is null"); person = em.find(Person.class, person.getGid());
From a JSF page I use
<h:inputText value="#{AddressPageBean.person.gid}" /> <h:commandButton value="FindPerson" action="#{AddressPageBean.findPerson}" />
which results in an the folllowing error in the log
00:48:57,361 INFO [STDOUT] >>>em is null 00:48:57,371 ERROR [[Faces Servlet]] Servlet.service() for servlet Faces Servlet threw exception javax.faces.FacesException: Error calling action method of component with id _id0:_id4 at org.apache.myfaces.application.ActionListenerImpl.processAction(ActionListenerImpl.java:74) at javax.faces.component.UICommand.broadcast(UICommand.java:106) at javax.faces.component.UIViewRoot._broadcastForPhase(UIViewRoot.java:90) at javax.faces.component.UIViewRoot.processApplication(UIViewRoot.java:164) at org.apache.myfaces.lifecycle.LifecycleImpl.invokeApplication(LifecycleImpl.java:316) at org.apache.myfaces.lifecycle.LifecycleImpl.execute(LifecycleImpl.java:86) at javax.faces.webapp.FacesServlet.service(FacesServlet.java:106) at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:252) at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:173) at org.jboss.web.tomcat.filters.ReplyHeaderFilter.doFilter(ReplyHeaderFilter.java:96) at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:202) at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:173) at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:213) at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:178) at org.jboss.web.tomcat.security.CustomPrincipalValve.invoke(CustomPrincipalValve.java:54) at org.jboss.web.tomcat.security.SecurityAssociationValve.invoke(SecurityAssociationValve.java:174) at org.jboss.web.tomcat.security.JaccContextValve.invoke(JaccContextValve.java:74) at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:126) at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:105) at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:107) at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:148) at org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:868) at org.apache.coyote.http11.Http11BaseProtocol$Http11ConnectionHandler.processConnection(Http11BaseProtocol.java:663) at org.apache.tomcat.util.net.PoolTcpEndpoint.processSocket(PoolTcpEndpoint.java:527) at org.apache.tomcat.util.net.MasterSlaveWorkerThread.run(MasterSlaveWorkerThread.java:112) at java.lang.Thread.run(Unknown Source) Caused by: javax.faces.el.EvaluationException: Exception while invoking expression #{AddressPageBean.findPerson} at org.apache.myfaces.el.MethodBindingImpl.invoke(MethodBindingImpl.java:153) at org.apache.myfaces.application.ActionListenerImpl.processAction(ActionListenerImpl.java:63) ... 25 more Caused by: java.lang.NullPointerException at info.agentbob.faces.AddressPage.findPerson(AddressPage.java:28) at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source) at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source) at java.lang.reflect.Method.invoke(Unknown Source) at org.apache.myfaces.el.MethodBindingImpl.invoke(MethodBindingImpl.java:129) ... 26 more
Looks like the persistence context cannot be found and therefore the EntityManager is NULL, but why ?
The persistence unit names match, therefore according to
http://trailblazer.demo.jboss.com/EJB3Trail/persistence/config/ I don't need a jboss-app.xml in the EAR as I have specified the persistence unit name.
What am I missing ?
Can I not inject an EntityManager in a JSF managed bean ? Would a bean have to be a "proper" EJB3 bean rather than a JSF managed bean for the EntityManager injection to work ?
Thanks for any ideas.