每次我请求entityManager为null时,请参见:
@Named
@ApplicationScoped
@AnBasicDAO
public class BasicDAOImpl implements BasicDAO, Serializable {
/**
*
*/
private static final long serialVersionUID = 1L;
@PersistenceContext(unitName="generalPU")
protected EntityManager entityManager;
这是我的persistence.xml:
<persistence-unit name="generalPU" transaction-type="RESOURCE_LOCAL">
<provider>org.hibernate.ejb.HibernatePersistence</provider>
<non-jta-data-source>java:/comp/env/jdbc/testeDS</non-jta-data-source>
<properties>
<property name="hibernate.show_sql" value="false" />
<property name="hibernate.format_sql" value="false" />
<property name="hibernate.hbm2ddl.auto" value="update" />
<property name="hibernate.cache.use_second_level_cache"
value="false" />
<property name="hibernate.cache.use_query_cache" value="false" />
<property name="hibernate.jdbc.batch_size" value="50" />
</properties>
</persistence-unit>
这是我在server.xml(tomcat)中的资源:
<Context docBase="/home/usertest/Programas/apache-tomcat-7.0.59/webapps/cardoso" path="/cardoso" reloadable="false" source="org.eclipse.jst.jee.server:cardoso">
<Resource name="jdbc/testeDS" auth="Container" type="javax.sql.DataSource"
username="postgres"
password="pgadmin"
driverClassName="org.postgresql.Driver"
url="jdbc:postgresql://localhost:5432/teste"
maxTotal="25"
maxIdle="10"
validationQuery="select 1" />
</Context>
我的context.xml:
<?xml version="1.0" encoding="UTF-8"?>
<Context>
<ResourceLink global="jdbc/sabrecadoDS" name="jdbc/testeDS" type="javax.sql.DataSource"/>
<Manager pathname=""/> <!-- disables storage of sessions across restarts -->
<Resource name="BeanManager"
auth="Container"
type="javax.enterprise.inject.spi.BeanManager"
factory="org.jboss.weld.resources.ManagerObjectFactory"/>
</Context>
有什么问题吗?EntityManager始终为null。不久前,我使用Spring(现在为CDI),并在applicationContext中定义了并正常工作。
CDI不理解@PersistenceContext
。因此将其更改为:
@Inject
protected EntityManager entityManager;
但是然后您必须定义一个EntityManager
地方,让我们说:
import javax.enterprise.context.ApplicationScoped;
import javax.enterprise.inject.Disposes;
import javax.enterprise.inject.Produces;
import javax.inject.Inject;
import javax.persistence.EntityManager;
import javax.persistence.EntityManagerFactory;
import javax.persistence.Persistence;
import org.apache.deltaspike.jpa.api.transaction.TransactionScoped;
public class CdiApplicationConfig {
@Inject
private EntityManagerFactory emf;
@Produces
@ApplicationScoped
public EntityManagerFactory createEntityManagerFactory() {
EntityManagerFactory emf = Persistence.createEntityManagerFactory("generalPU");
return emf;
}
public void close(@Disposes EntityManagerFactory emf) {
emf.close();
}
@Produces
@TransactionScoped // is a bit better than @RequestScoped because it won't allow perform injection outside transaction context
public EntityManager createEntityManager() {
return emf.createEntityManager();
}
public void close(@Disposes EntityManager em) {
if (em.isOpen()) {
em.close();
}
}
}
上面的代码DeltaSpike
用于事务管理-但是您可以使用任何您想要的东西。
另一个提示:我不确定java:/comp
在里面引用的数据源名称之间是否允许使用斜线persistence.xml
,因此也请检查:
<non-jta-data-source>java:comp/env/jdbc/testeDS</non-jta-data-source>
如您所见,CDI与Spring非常相似。
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