EntityManager is null. @PersistenceContext not working
Hi Folks,
I'm new in EJB3 and Hibernate. I was creating one application using EJB3 and Hibernate but due to EntityManager is always null. Therefore can not make any transaction. Can you please help me ?
My persistence.xml file looks like below -
<?xml version="1.0" encoding="UTF-8"?>
<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="JSFTestPU" transaction-type="JTA">
<provider>org.hibernate.ejb.HibernatePersistence</provider>
<jta-data-source>java:jboss/datasources/PostgresDS</jta-data-source>
<properties>
<property name="hibernate.dialect" value="org.hibernate.dialect.PostgreSQLDialect" />
<property name="hibernate.show_sql" value="true" />
<property name="hibernate.format_sql" value="true" />
<property name="hibernate.max_fetch_depth" value="3" />
<property name="hibernate.default_schema" value="postgres" />
<property name="hibernate.jdbc.batch_size" value="650" />
<property name="hibernate.connection.driver_class" value="org.postgresql.Driver" />
<property name="hibernate.connection.url" value="jdbc:postgresql://localhost:5432/test" />
<property name="hibernate.connection.username" value="postgres" />
<property name="hibernate.connection.password" value="pgadmin" />
<property name="hibernate.connection.autocommit" value="true" />
</properties>
</persistence-unit>
</persistence>
I'm using JBOSS AS 7.1.1 application server and Database is Postgresql DB.
Standalone.xml configuration file looks like -
<datasource jta="true" jndi-name="java:jboss/datasources/PostgresDS" pool-name="PostgresDS" enabled="true">
<connection-url>jdbc:postgresql://localhost:5432/test</connection-url>
<driver-class>org.postgresql.Driver</driver-class>
<driver>postgresql-jdbc4</driver>
<pool>
<min-pool-size>5</min-pool-size>
<max-pool-size>20</max-pool-size>
<prefill>true</prefill>
</pool>
<security>
<user-name>postgres</user-name>
<password>********</password>
</security>
</datasource>
<drivers>
<driver name="postgresql-jdbc4" module="com.pgserver.jdbc"/>
</drivers>
My DAO class is like below which an abstract class extended in other DAO and used -
abstract class GenericDAO<T> implements Serializable {
private static final long serialVersionUID = 1L;
@PersistenceContext(unitName="JSFTestPU")
private EntityManager em; ///// Here EntityManager is always returned as NULL
private Class<T> entityClass;
public void beginTransaction() {
try{
em.getTransaction().begin();
}catch(Exception e1){
System.out.println(e1.getMessage());
e1.printStackTrace();
System.out.println("Entity Manager :"+em);
}
}
public void commit() {
em.getTransaction().commit();
}
public void rollback() {
em.getTransaction().rollback();
}
public void closeTransaction() {
em.close();
}
public void commitAndCloseTransaction() {
commit();
closeTransaction();
}
public void flush() {
em.flush();
}
public void joinTransaction() {
em.joinTransaction();
}
public GenericDAO(Class<T> entityClass) {
this.entityClass = entityClass;
}
public T save(T entity) {
try {
beginTransaction();
em.persist(entity);
commitAndCloseTransaction();
} catch (Exception e) {
e.printStackTrace();
}
return entity;
}
....
....
}
The problem is EntityManager is always returned as NULL. Can you anybody help me to resolve this problem ?????
Thanks in advance.
Jayanta P.
