Which container are you using? And have you defined in this container your jta-data-source(jdbc/__adressbook)?
PersistanceUnit annotation do not inject
Question
I have a small project for education. JPA-Servlet-JSP. Now I want to use PersistanceUnit annotation:
public class UsersListServlet extends HttpServlet {
@PersistenceUnit
private EntityManagerFactory emf;
protected void processRequest(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
EntityManager em = null;
try {
em = emf.createEntityManager();
//query for all the persons in database
List persons = em.createQuery("select u from Users u").getResultList();
request.setAttribute("usersList",persons);
//Forward to the jsp page for rendering
request.getRequestDispatcher("UsersList.jsp").forward(request, response);
} catch (Exception ex) {
throw new ServletException(ex);
} finally {
//close the em to release any resources held up by the persistebce provider
if(em != null) {
em.close();
}
}
response.setContentType("text/html;charset=UTF-8");
}
but I see NPE when try emf.createEntityManager();
My persistance.xml:
<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="AdressBookPU">
<provider>org.eclipse.persistence.jpa.PersistenceProvider</provider>
<jta-data-source>jdbc/__adressbook</jta-data-source>
<class>com.prokopenko.adressbook.entity.Users</class>
<class>com.prokopenko.adressbook.entity.MobilePhone</class>
</persistence-unit>
</persistence>
Its a maven project and persistance.xml located src/main/resources/META-INF (like in j2ee7 tutorial). UPDATE Tried:
@PersistenceContext(unitName = "AdressBookPU")
private EntityManager em;
and
@PersistenceUnit(unitName="AdressBookPU")
private EntityManagerFactory emf;
Solution
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