Cant persist data: JTA EntityManager не может использовать getTransaction()

Question

При попытке сохранить сущность я получаю следующее исключение.

public class MyClass { 

    EntityManagerFactory emFactory; 
    EntityManager entityManager; 

    public MyClass(){ 
     emFactory = Persistence.createEntityManagerFactory("persistenceUnit"); 
     entityManager = emFactory.createEntityManager(); 
    } 

    public void getData() {  
     try { 
      TrigData trigData = new TrigData(); 
      trigData.setKey("abc");  
      entityManager.getTransaction().begin(); 
      entityManager.persist(trigData); 
      entityManager.getTransaction().commit(); 
     } catch (Exception e) { 
      e.printStackTrace(); 
     } 

    } 


19:31:51,508 ERROR [stderr] (default task-6) java.lang.IllegalStateException: A JTA EntityManager cannot use getTransaction() 
19:31:51,508 ERROR [stderr] (default task-6) at org.hibernate.jpa.spi.AbstractEntityManagerImpl.getTransaction(AbstractEntityManagerImpl.java:1368) 
19:31:51,509 ERROR [stderr] (default task-6) at com.xyz.services.MyClass.getData(MyClass.java:42) 
19:31:51,509 ERROR [stderr] (default task-6) at com.xyz.services.MyClass$Proxy$_$$_WeldClientProxy.getData(Unknown Source) 
19:31:51,509 ERROR [stderr] (default task-6) at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) 
19:31:51,510 ERROR [stderr] (default task-6) at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57) 
19:31:51,510 ERROR [stderr] (default task-6) at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) 
19:31:51,510 ERROR [stderr] (default task-6) at java.lang.reflect.Method.invoke(Method.java:606) 
19:31:51,510 ERROR [stderr] (default task-6) at com.sun.jersey.spi.container.JavaMethodInvokerFactory$1.invoke(JavaMethodInvokerFactory.java:60) 
19:31:51,511 ERROR [stderr] (default task-6) at com.sun.jersey.server.impl.model.method.dispatch.AbstractResourceMethodDispatchProvider$VoidOutInvoker._dispatch(AbstractResourceMethodDispatchProvider.java:167) 
19:31:51,511 ERROR [stderr] (default task-6) at com.sun.jersey.server.impl.model.method.dispatch.ResourceJavaMethodDispatcher.dispatch(ResourceJavaMethodDispatcher.java:75) 
19:31:51,511 ERROR [stderr] (default task-6) at com.sun.jersey.server.impl.uri.rules.HttpMethodRule.accept(HttpMethodRule.java:302) 
19:31:51,512 ERROR [stderr] (default task-6) at com.sun.jersey.server.impl.uri.rules.RightHandPathRule.accept(RightHandPathRule.java:147) 
19:31:51,512 ERROR [stderr] (default task-6) at com.sun.jersey.server.impl.uri.rules.ResourceClassRule.accept(ResourceClassRule.java:108) 
19:31:51,513 ERROR [stderr] (default task-6) at com.sun.jersey.server.impl.uri.rules.RightHandPathRule.accept(RightHandPathRule.java:147) 

persistence.xml:

<persistence 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" 
      version="2.0"> 

    <persistence-unit name="persistenceUnit" > 
     <provider>org.hibernate.ejb.HibernatePersistence</provider> 
     <jta-data-source>java:jboss/datasources/PostgresDS</jta-data-source>  
     <class>com.xyz.TrigData</class> 

     <properties> 
      <property name="hibernate.transaction.jta.platform" value="org.hibernate.service.jta.platform.internal.JBossStandAloneJtaPlatform" /> 
      <property name="hibernate.dialect" value="org.hibernate.dialect.PostgreSQLDialect" /> 
      <property name="hibernate.hbm2ddl.auto" value="update" /> 
     </properties> 
    </persistence-unit> 

</persistence> 

Answer 1

Если вы пытаетесь развернуть на Wildfly, а затем получить ваши EntityManager с @PersistenceContext аннотацию. Все quickstarts Wildfly есть класс, который @Produces сущностей менеджер, который будет введен в другие бобы:

public class Resources { 
    @Produces 
    @PersistenceContext 
    private EntityManager em; 

    @Produces 
    public Logger produceLog(InjectionPoint injectionPoint) { 
     return Logger.getLogger(injectionPoint.getMember().getDeclaringClass().getName()); 
    } 

    @Produces 
    @RequestScoped 
    public FacesContext produceFacesContext() { 
     return FacesContext.getCurrentInstance(); 
    } 
} 

Он будет использоваться как так:

@Stateless 
public class Service { 

    @Inject 
    private EntityManager em; 

Полезный CrossReference: How to inject EntityManager in CDI (weld)?