Null EntityManager / EJB注入MDB

时间:2016-04-04 03:38:56

标签: java java-ee ejb-3.1 weblogic12c message-driven-bean

我有一个部署到WebLogic 12.1.3的消息驱动bean(MDB)。我尝试使用@PersistenceContext注释将实体管理器注入MDB,但实体管理器为空。我也试过注入一个简单的无状态会话bean,它也是null。但是,MessageDrivenContext被正确注入。

我错过了什么?从我可以告诉搜索SO和Google的内容来看,您应该能够将EJB和实体管理器注入到MDB中。我能够将它们注入应用程序的其他部分就好了。为什么不是MDB?

备注:

  • 我正在尝试使用容器管理的交易
  • MDB与其他两个(也不起作用)打包在一个EAR内的单个JAR中
  • JAR有一个persistence.xml,可以在应用程序的其他部分使用
  • JAR中也有一个beans.xml
  • 我尝试了许多事务注释和ActivationConfig属性的组合(下面)

MDB:

@MessageDriven(activationConfig =  {
    @ActivationConfigProperty(propertyName="acknowledgeMode", propertyValue="Auto-acknowledge"),
    @ActivationConfigProperty(propertyName="destinationJndiName", propertyValue="jms/MyTopic"),
    @ActivationConfigProperty(propertyName="destinationType", propertyValue="javax.jms.Topic"),
    @ActivationConfigProperty(propertyName="subscriptionDurability", propertyValue="Durable"),
    @ActivationConfigProperty(propertyName="connectionFactoryJndiName", propertyValue="weblogic.jms.XAConnectionFactory"),
    @ActivationConfigProperty(propertyName="transaction-type", propertyValue="Container"),
    @ActivationConfigProperty(propertyName="trans-attribute", propertyValue="Required"),
    @ActivationConfigProperty(propertyName="trans-timeout-seconds", propertyValue="120"),
    @ActivationConfigProperty(propertyName="topicMessagesDistributionMode", propertyValue="One-Copy-Per-Application")
})
@TransactionTimeoutSeconds(120)
@TransactionManagement(TransactionManagementType.CONTAINER)
public class MyMDB implements MessageListener {

    @PersistenceContext(unitName="myPersistenceUnit")
    private EntityManager entityManager;

    @Resource
    private MessageDrivenContext context;

    @EJB
    private HelloWorld helloWorld;

    @Override
    @TransactionAttribute(value = TransactionAttributeType.REQUIRED)
    public void onMessage(final Message message) {

        //entityManager is null
        //context is NOT null
        //helloWorld (EJB) is null
    }
}

的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="myPersistenceUnit" transaction-type="JTA">

        <jta-data-source>MyDataSource</jta-data-source>

        <mapping-file>META-INF/queries.xml</mapping-file>

        <exclude-unlisted-classes>false</exclude-unlisted-classes>

        <shared-cache-mode>NONE</shared-cache-mode>

        <properties>
            <property name="javax.persistence.lock.timeout" value="30000"/>
        </properties>

    </persistence-unit>
</persistence>

EJB:

@Stateless
@LocalBean
public class HelloWorld {

    @PersistenceContext(unitName="myPersistenceUnit")
    private EntityManager entityManager;


    public String sayHello() {
        return "Hello World";
    }


    public EntityManager getEntityManager() {
        return entityManager;
    }
}

0 个答案:

没有答案