Java, EntityManager always null when using JTA datasource
Hello all. New member here, and new to JBoss/Wildfly. I have been stuck on a problem for a few days now. I am trying to setup a simple REST web service to use JPA to manipulate a MySQL database. I am using Wildfly 8.0 Final with Hibernate 4.3. Here is how my Eclipse project is setup:
PersonApp.ear (Enterprise project) | |---PersonData.jar (JPA project) | | | |---Person (Entity) | |---PersonManager | |---persistence.xml (in META-INF) | |---PersonRest.war (Web project) | |---PersonService
PersonService (in PersonRest project) contains one @GET method which calls PersonManager.
PersonManager is a wrapper for EntityManager. This is where my application is failing. I can't get a handle on EntityManager.
PersonService:
@Path("/PersonService")
public class PersonService {
@GET
@Produces("text/plain")
public String getAllPersons() {
PersonManager manager = new PersonManager();
List<Person> list = manager.findAll(); //fails with null pointer
}
}
PersonManager:
public class PersonManager {
public List<Person> findAll() {
EntityManagerFactory emf = Persistence.createEntityManagerFactory("PersonData"); //returns null
EntityManager em = emf.createEntityManager(); //null pointer exception on this line. emf is null
List<Person> list = em.createQuery("SELECT p FROM Person p").getResultList();
return list;
}
}
persistence.xml:
<?xml version="1.0" encoding="UTF-8"?> <persistence version="2.1" xmlns="http://xmlns.jcp.org/xml/ns/persistence" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://xmlns.jcp.org/xml/ns/persistence http://xmlns.jcp.org/xml/ns/persistence/persistence_2_1.xsd"> <persistence-unit name="PersonData" transaction-type="JTA"> <provider>org.hibernate.jpa.HibernatePersistenceProvider</provider> <jta-data-source>java:jboss/datasources/MySqlDS</jta-data-source> <class>com.csc.data.Person</class> <properties> <property name="hibernate.dialect" value="org.hibernate.dialect.MySQL5Dialect"/> <property name="hibernate.hbm2ddl.auto" value="create-drop"/> </properties> </persistence-unit> </persistence>
Here is the Wildfly startup output:
14:31:14,607 INFO [org.jboss.modules] (main) JBoss Modules version 1.3.0.Final
14:31:14,841 INFO [org.jboss.msc] (main) JBoss MSC version 1.2.0.Final
14:31:14,919 INFO [org.jboss.as] (MSC service thread 1-6) JBAS015899: WildFly 8.0.0.Final "WildFly" starting
14:31:15,871 INFO [org.jboss.as.server.deployment.scanner] (DeploymentScanner-threads - 1) JBAS015003: Found PersonApp.ear in deployment directory. To trigger deployment create a file called PersonApp.ear.dodeploy
14:31:15,887 INFO [org.jboss.as.server] (Controller Boot Thread) JBAS015888: Creating http management service using socket-binding (management-http)
14:31:15,903 INFO [org.xnio] (MSC service thread 1-8) XNIO version 3.2.0.Final
14:31:15,919 INFO [org.xnio.nio] (MSC service thread 1-8) XNIO NIO Implementation Version 3.2.0.Final
14:31:15,934 INFO [org.jboss.as.clustering.infinispan] (ServerService Thread Pool -- 33) JBAS010280: Activating Infinispan subsystem.
14:31:15,950 INFO [org.jboss.as.security] (ServerService Thread Pool -- 46) JBAS013171: Activating Security Subsystem
14:31:15,966 INFO [org.jboss.as.webservices] (ServerService Thread Pool -- 50) JBAS015537: Activating WebServices Extension
14:31:15,997 INFO [org.wildfly.extension.undertow] (MSC service thread 1-6) JBAS017502: Undertow 1.0.0.Final starting
14:31:15,997 INFO [org.wildfly.extension.undertow] (ServerService Thread Pool -- 49) JBAS017502: Undertow 1.0.0.Final starting
14:31:15,997 INFO [org.jboss.as.security] (MSC service thread 1-2) JBAS013170: Current PicketBox version=4.0.20.Final
14:31:15,997 INFO [org.jboss.as.naming] (ServerService Thread Pool -- 41) JBAS011800: Activating Naming Subsystem
14:31:15,997 INFO [org.jboss.as.jsf] (ServerService Thread Pool -- 39) JBAS012615: Activated the following JSF Implementations: [main]
14:31:16,028 INFO [org.jboss.as.connector.logging] (MSC service thread 1-5) JBAS010408: Starting JCA Subsystem (IronJacamar 1.1.3.Final)
14:31:16,075 INFO [org.jboss.as.naming] (MSC service thread 1-5) JBAS011802: Starting Naming Service
14:31:16,075 INFO [org.jboss.as.connector.subsystems.datasources] (ServerService Thread Pool -- 28) JBAS010403: Deploying JDBC-compliant driver class org.h2.Driver (version 1.3)
14:31:16,090 INFO [org.jboss.as.mail.extension] (MSC service thread 1-6) JBAS015400: Bound mail session [java:jboss/mail/Default]
14:31:16,106 INFO [org.jboss.as.connector.subsystems.datasources] (ServerService Thread Pool -- 28) JBAS010404: Deploying non-JDBC-compliant driver class com.mysql.jdbc.Driver (version 5.1)
14:31:16,106 INFO [org.jboss.as.connector.deployers.jdbc] (MSC service thread 1-4) JBAS010417: Started Driver service with driver-name = h2
14:31:16,106 INFO [org.jboss.as.connector.deployers.jdbc] (MSC service thread 1-4) JBAS010417: Started Driver service with driver-name = com.mysql
14:31:16,184 INFO [org.wildfly.extension.undertow] (ServerService Thread Pool -- 49) JBAS017527: Creating file handler for path C:\wildfly-8.0.0.Final/welcome-content
14:31:16,200 INFO [org.jboss.remoting] (MSC service thread 1-1) JBoss Remoting version 4.0.0.Final
14:31:16,434 INFO [org.wildfly.extension.undertow] (MSC service thread 1-2) JBAS017525: Started server default-server.
14:31:16,543 INFO [org.wildfly.extension.undertow] (MSC service thread 1-2) JBAS017531: Host default-host starting
14:31:16,605 INFO [org.wildfly.extension.undertow] (MSC service thread 1-6) JBAS017519: Undertow HTTP listener default listening on localhost/127.0.0.1:8080
14:31:16,652 INFO [org.jboss.as.connector.subsystems.datasources] (MSC service thread 1-4) JBAS010400: Bound data source [java:jboss/datasources/MySqlDS]
14:31:16,730 INFO [org.jboss.as.server.deployment] (MSC service thread 1-4) JBAS015876: Starting deployment of "PersonApp.ear" (runtime-name: "PersonApp.ear")
14:31:16,746 INFO [org.jboss.as.server.deployment.scanner] (MSC service thread 1-7) JBAS015012: Started FileSystemDeploymentService for directory C:\wildfly-8.0.0.Final\standalone\deployments
14:31:16,761 INFO [org.jboss.as.connector.subsystems.datasources] (MSC service thread 1-7) JBAS010400: Bound data source [java:jboss/datasources/ExampleDS]
14:31:16,824 INFO [org.jboss.as.server.deployment] (MSC service thread 1-3) JBAS015876: Starting deployment of "null" (runtime-name: "PersonRest.war")
14:31:16,855 INFO [org.jboss.ws.common.management] (MSC service thread 1-6) JBWS022052: Starting JBoss Web Services - Stack CXF Server 4.2.3.Final
14:31:16,870 INFO [org.jboss.as.jpa] (MSC service thread 1-3) JBAS011401: Read persistence.xml for PersonData
14:31:16,933 INFO [org.jboss.as.jpa] (ServerService Thread Pool -- 52) JBAS011409: Starting Persistence Unit (phase 1 of 2) Service 'PersonApp.ear#PersonData'
14:31:16,948 INFO [org.hibernate.jpa.internal.util.LogHelper] (ServerService Thread Pool -- 52) HHH000204: Processing PersistenceUnitInfo [
name: PersonData
...]
14:31:16,996 INFO [org.hibernate.Version] (ServerService Thread Pool -- 52) HHH000412: Hibernate Core {4.3.1.Final}
14:31:17,012 INFO [org.hibernate.cfg.Environment] (ServerService Thread Pool -- 52) HHH000206: hibernate.properties not found
14:31:17,012 INFO [org.hibernate.cfg.Environment] (ServerService Thread Pool -- 52) HHH000021: Bytecode provider name : javassist
14:31:17,152 INFO [org.jboss.as.jpa] (ServerService Thread Pool -- 52) JBAS011409: Starting Persistence Unit (phase 2 of 2) Service 'PersonApp.ear#PersonData'
14:31:17,277 INFO [org.hibernate.annotations.common.Version] (ServerService Thread Pool -- 52) HCANN000001: Hibernate Commons Annotations {4.0.4.Final}
14:31:17,511 INFO [org.hibernate.dialect.Dialect] (ServerService Thread Pool -- 52) HHH000400: Using dialect: org.hibernate.dialect.MySQL5Dialect
14:31:17,589 INFO [org.hibernate.hql.internal.ast.ASTQueryTranslatorFactory] (ServerService Thread Pool -- 52) HHH000397: Using ASTQueryTranslatorFactory
14:31:17,620 INFO [org.hibernate.validator.internal.util.Version] (ServerService Thread Pool -- 52) HV000001: Hibernate Validator 5.0.3.Final
14:31:17,885 INFO [org.hibernate.tool.hbm2ddl.SchemaExport] (ServerService Thread Pool -- 52) HHH000227: Running hbm2ddl schema export
14:31:17,932 INFO [org.hibernate.tool.hbm2ddl.SchemaExport] (ServerService Thread Pool -- 52) HHH000230: Schema export complete
14:31:18,197 INFO [org.jboss.resteasy.spi.ResteasyDeployment] (MSC service thread 1-2) Deploying javax.ws.rs.core.Application: class com.csc.rest.service.PersonRest
14:31:18,197 INFO [org.jboss.resteasy.spi.ResteasyDeployment] (MSC service thread 1-2) Adding singleton resource com.csc.rest.service.PersonService from Application class com.csc.rest.service.PersonRest
14:31:18,323 INFO [org.wildfly.extension.undertow] (MSC service thread 1-2) JBAS017534: Registered web context: /PersonRest
14:31:18,370 INFO [org.jboss.as.server] (ServerService Thread Pool -- 29) JBAS018559: Deployed "PersonApp.ear" (runtime-name : "PersonApp.ear")
14:31:18,417 INFO [org.jboss.as] (Controller Boot Thread) JBAS015961: Http management interface listening on http://127.0.0.1:9990/management
14:31:18,417 INFO [org.jboss.as] (Controller Boot Thread) JBAS015951: Admin console listening on http://127.0.0.1:9990
14:31:18,417 INFO [org.jboss.as] (Controller Boot Thread) JBAS015874: WildFly 8.0.0.Final "WildFly" started in 4059ms - Started 291 of 351 services (98 services are lazy, passive or on-demand)
Here is the error when I access the service through the web browser:
14:32:06,221 INFO [org.hibernate.jpa.internal.util.LogHelper] (default task-2) HHH000204: Processing PersistenceUnitInfo [ name: PersonData ...] 14:32:06,236 INFO [org.hibernate.dialect.Dialect] (default task-2) HHH000400: Using dialect: org.hibernate.dialect.MySQL5Dialect 14:32:06,236 INFO [org.hibernate.hql.internal.ast.ASTQueryTranslatorFactory] (default task-2) HHH000397: Using ASTQueryTranslatorFactory 14:32:06,252 INFO [org.hibernate.tool.hbm2ddl.SchemaExport] (default task-2) HHH000227: Running hbm2ddl schema export 14:32:06,268 INFO [org.hibernate.tool.hbm2ddl.SchemaExport] (default task-2) HHH000230: Schema export complete 14:32:06,300 ERROR [io.undertow.request] (default task-2) UT005023: Exception handling request to /PersonRest/PersonService: org.jboss.resteasy.spi.UnhandledException: java.lang.NullPointerException at org.jboss.resteasy.core.ExceptionHandler.handleApplicationException(ExceptionHandler.java:76) [resteasy-jaxrs-3.0.6.Final.jar:] at org.jboss.resteasy.core.ExceptionHandler.handleException(ExceptionHandler.java:212) [resteasy-jaxrs-3.0.6.Final.jar:] at org.jboss.resteasy.core.SynchronousDispatcher.writeException(SynchronousDispatcher.java:149) [resteasy-jaxrs-3.0.6.Final.jar:] at org.jboss.resteasy.core.SynchronousDispatcher.invoke(SynchronousDispatcher.java:372) [resteasy-jaxrs-3.0.6.Final.jar:] at org.jboss.resteasy.core.SynchronousDispatcher.invoke(SynchronousDispatcher.java:179) [resteasy-jaxrs-3.0.6.Final.jar:] at org.jboss.resteasy.plugins.server.servlet.ServletContainerDispatcher.service(ServletContainerDispatcher.java:220) [resteasy-jaxrs-3.0.6.Final.jar:] at org.jboss.resteasy.plugins.server.servlet.HttpServletDispatcher.service(HttpServletDispatcher.java:56) [resteasy-jaxrs-3.0.6.Final.jar:] at org.jboss.resteasy.plugins.server.servlet.HttpServletDispatcher.service(HttpServletDispatcher.java:51) [resteasy-jaxrs-3.0.6.Final.jar:] at javax.servlet.http.HttpServlet.service(HttpServlet.java:790) [jboss-servlet-api_3.1_spec-1.0.0.Final.jar:1.0.0.Final] at io.undertow.servlet.handlers.ServletHandler.handleRequest(ServletHandler.java:85) [undertow-servlet-1.0.0.Final.jar:1.0.0.Final] at io.undertow.servlet.handlers.security.ServletSecurityRoleHandler.handleRequest(ServletSecurityRoleHandler.java:61) [undertow-servlet-1.0.0.Final.jar:1.0.0.Final] at io.undertow.servlet.handlers.ServletDispatchingHandler.handleRequest(ServletDispatchingHandler.java:36) [undertow-servlet-1.0.0.Final.jar:1.0.0.Final] at org.wildfly.extension.undertow.security.SecurityContextAssociationHandler.handleRequest(SecurityContextAssociationHandler.java:78) at io.undertow.server.handlers.PredicateHandler.handleRequest(PredicateHandler.java:25) [undertow-core-1.0.0.Final.jar:1.0.0.Final] at io.undertow.servlet.handlers.security.SSLInformationAssociationHandler.handleRequest(SSLInformationAssociationHandler.java:113) [undertow-servlet-1.0.0.Final.jar:1.0.0.Final] at io.undertow.security.handlers.AuthenticationCallHandler.handleRequest(AuthenticationCallHandler.java:52) [undertow-core-1.0.0.Final.jar:1.0.0.Final] at io.undertow.security.handlers.AbstractConfidentialityHandler.handleRequest(AbstractConfidentialityHandler.java:45) [undertow-core-1.0.0.Final.jar:1.0.0.Final] at io.undertow.servlet.handlers.security.ServletConfidentialityConstraintHandler.handleRequest(ServletConfidentialityConstraintHandler.java:61) [undertow-servlet-1.0.0.Final.jar:1.0.0.Final] at io.undertow.servlet.handlers.security.CachedAuthenticatedSessionHandler.handleRequest(CachedAuthenticatedSessionHandler.java:70) [undertow-servlet-1.0.0.Final.jar:1.0.0.Final] at io.undertow.security.handlers.SecurityInitialHandler.handleRequest(SecurityInitialHandler.java:76) [undertow-core-1.0.0.Final.jar:1.0.0.Final] at io.undertow.server.handlers.PredicateHandler.handleRequest(PredicateHandler.java:25) [undertow-core-1.0.0.Final.jar:1.0.0.Final] at org.wildfly.extension.undertow.security.jacc.JACCContextIdHandler.handleRequest(JACCContextIdHandler.java:61) at io.undertow.server.handlers.PredicateHandler.handleRequest(PredicateHandler.java:25) [undertow-core-1.0.0.Final.jar:1.0.0.Final] at io.undertow.server.handlers.PredicateHandler.handleRequest(PredicateHandler.java:25) [undertow-core-1.0.0.Final.jar:1.0.0.Final] at io.undertow.servlet.handlers.ServletInitialHandler.handleFirstRequest(ServletInitialHandler.java:240) [undertow-servlet-1.0.0.Final.jar:1.0.0.Final] at io.undertow.servlet.handlers.ServletInitialHandler.dispatchRequest(ServletInitialHandler.java:227) [undertow-servlet-1.0.0.Final.jar:1.0.0.Final] at io.undertow.servlet.handlers.ServletInitialHandler.access$000(ServletInitialHandler.java:73) [undertow-servlet-1.0.0.Final.jar:1.0.0.Final] at io.undertow.servlet.handlers.ServletInitialHandler$1.handleRequest(ServletInitialHandler.java:146) [undertow-servlet-1.0.0.Final.jar:1.0.0.Final] at io.undertow.server.Connectors.executeRootHandler(Connectors.java:168) [undertow-core-1.0.0.Final.jar:1.0.0.Final] at io.undertow.server.HttpServerExchange$1.run(HttpServerExchange.java:687) [undertow-core-1.0.0.Final.jar:1.0.0.Final] at java.util.concurrent.ThreadPoolExecutor.runWorker(Unknown Source) [rt.jar:1.7.0_51] at java.util.concurrent.ThreadPoolExecutor$Worker.run(Unknown Source) [rt.jar:1.7.0_51] at java.lang.Thread.run(Unknown Source) [rt.jar:1.7.0_51] Caused by: java.lang.NullPointerException at org.hibernate.engine.transaction.internal.jta.JtaStatusHelper.getStatus(JtaStatusHelper.java:76) [hibernate-core-4.3.1.Final.jar:4.3.1.Final] at org.hibernate.engine.transaction.internal.jta.JtaStatusHelper.isActive(JtaStatusHelper.java:118) [hibernate-core-4.3.1.Final.jar:4.3.1.Final] at org.hibernate.engine.transaction.internal.jta.CMTTransaction.join(CMTTransaction.java:149) [hibernate-core-4.3.1.Final.jar:4.3.1.Final] at org.hibernate.jpa.spi.AbstractEntityManagerImpl.joinTransaction(AbstractEntityManagerImpl.java:1602) [hibernate-entitymanager-4.3.1.Final.jar:4.3.1.Final] at org.hibernate.jpa.spi.AbstractEntityManagerImpl.postInit(AbstractEntityManagerImpl.java:210) [hibernate-entitymanager-4.3.1.Final.jar:4.3.1.Final] at org.hibernate.jpa.internal.EntityManagerImpl.<init>(EntityManagerImpl.java:91) [hibernate-entitymanager-4.3.1.Final.jar:4.3.1.Final] at org.hibernate.jpa.internal.EntityManagerFactoryImpl.internalCreateEntityManager(EntityManagerFactoryImpl.java:345) [hibernate-entitymanager-4.3.1.Final.jar:4.3.1.Final] at org.hibernate.jpa.internal.EntityManagerFactoryImpl.createEntityManager(EntityManagerFactoryImpl.java:313) [hibernate-entitymanager-4.3.1.Final.jar:4.3.1.Final] at com.csc.data.PersonManager.findAll(PersonManager.java:51) [PersonData.jar:] at com.csc.rest.service.PersonService.getAllPersons(PersonService.java:21) [classes:] at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) [rt.jar:1.7.0_51] at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source) [rt.jar:1.7.0_51] at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source) [rt.jar:1.7.0_51] at java.lang.reflect.Method.invoke(Unknown Source) [rt.jar:1.7.0_51] at org.jboss.resteasy.core.MethodInjectorImpl.invoke(MethodInjectorImpl.java:137) [resteasy-jaxrs-3.0.6.Final.jar:] at org.jboss.resteasy.core.ResourceMethodInvoker.invokeOnTarget(ResourceMethodInvoker.java:280) [resteasy-jaxrs-3.0.6.Final.jar:] at org.jboss.resteasy.core.ResourceMethodInvoker.invoke(ResourceMethodInvoker.java:234) [resteasy-jaxrs-3.0.6.Final.jar:] at org.jboss.resteasy.core.ResourceMethodInvoker.invoke(ResourceMethodInvoker.java:221) [resteasy-jaxrs-3.0.6.Final.jar:] at org.jboss.resteasy.core.SynchronousDispatcher.invoke(SynchronousDispatcher.java:356) [resteasy-jaxrs-3.0.6.Final.jar:] ... 29 more
Any idea what I am missing? One odd thing is that if I change this from a JTA jboss datasource to a local resource and specify my DB connection in persistence.xml, everything works fine. In Wildfly admin, "Test Connection" on my datasource works properly, returning "Successfully connected to database MySqlDS", so I am assuming the datasource is configured properly. Also, another possible clue: all data in table Person is being dropped on Wildfly startup. I assume this is another clue that the datasource is configured properly and this is expected using <property name="hibernate.hbm2ddl.auto" value="create-drop"/>. So if there is no datasource problem, and it works with resource-local but not with JTA, what could I be missing?
Thanks, Dave
EDIT:
I have come across the following documentation, which makes me think my current way of getting entity manager is incorrect for JTA:
--------------------------------------------------------------------------
With <persistence-unit transaction-type="JTA"> the container will do EntityManager (PersistenceContext/Cache) creating and tracking...
- You cannot use the EntityManagerFactory to get an EntityManager
- You can only get an EntityManager supplied by the container
- An EntityManager can be injected via the @PersistenceContext annotation only (not @PersistenceUnit)
--------------------------------------------------------------------------
After reading this, I have tried changing how PersonManager retrieves EntityManager
@Stateless
public class PersonManager {
@PersistenceContext(unitName="PersonData")
EntityManager em;
public List<Person> findAll() {
//EntityManagerFactory emf = Persistence.createEntityManagerFactory("PersonData"); //returns null
//EntityManager em = emf.createEntityManager(); //null pointer exception on this line. emf is null
List<Person> list = em.createQuery("SELECT p FROM Person p").getResultList();
return list;
}
}
This change did not seem to resolve anything. EntityManager is always null in this case.
