Persisting new Entity to existing Database JPA - database

Question

I've created a database connection and some entities, now I'm trying to test the functionality of my database. I have a User entity class, which has a unique username along with some other information. Right now I'm trying to simply create a new User and Profile and map them together, then persist them. When I test the code, it successfully runs through, but the DB is not updated. Here's what I have:
package servlets;
import java.io.IOException;
import java.util.ArrayList;
import java.util.List;
import javax.annotation.Resource;
import javax.persistence.EntityManager;
import javax.persistence.EntityManagerFactory;
import javax.persistence.Persistence;
import javax.persistence.PersistenceUnit;
import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.transaction.UserTransaction;
import entities.Profile;
import entities.User;
#WebServlet("/NewUser")
public class NewUser extends HttpServlet {
#Resource
UserTransaction utx;
#PersistenceUnit
EntityManagerFactory emf;
protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
String username = request.getParameter("username");
String email = request.getParameter("email");
String firstname = request.getParameter("firstname");
String lastname = request.getParameter("lastname");
String phone = request.getParameter("phone");
String address1 = request.getParameter("address1");
String address2 = request.getParameter("address2");
try {
utx.begin();
EntityManager em = emf.createEntityManager();
//create User & Profile
User u = new User();
u.setUsername(username);
Profile p = new Profile();
p.setUser(username);
//add email to profile's list
List<String> emails = new ArrayList<String>();
emails.add(email);
p.setEmails(emails);
//assign the profile to the user
u.setProfile(p);
//persist user to the database
em.persist(u);
utx.commit();
em.close();
emf.close();
} catch (Exception e) {
e.printStackTrace();
}
response.sendRedirect("index.jsp");
}
}
Am I doing something wrong or is the problem somewhere else in the application?
EDIT: I found the following error: Exception Description: Unable to acquire a connection from driver [null], user [null] and URL [null]. Verify that you have set the expected driver class and URL. Check your login, persistence.xml or sessions.xml resource. The jdbc.driver property should be set to a class that is compatible with your database platform
I'm not sure what to make of the error, however...I've checked my db connection and everything seems to be in order. :/
My persistence.xml file:
<?xml version="1.0" encoding="UTF-8"?>
<persistence version="2.0" 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">
<persistence-unit name="myPersistenceUnit" >
<jta-data-source>jdbc/mydatasource</jta-data-source>
<class>entities.User</class>
<class>entities.Profile</class>
<class>entities.Message</class>
<class>entities.Image</class>
<properties>
<property name="eclipselink.ddl-generation" value="create-tables"/>
<property name="eclipselink.ddl-generation.output-mode" value="both"/>
</properties>
</persistence-unit>
</persistence>

Answer 1

I have never use container managed transactions but your persistence.xml at least have.
<persistence-unit name="myPersistenceUnit" transaction-type="JTA">