Hibernate DAO Can not set java.util.Date field User.created to User

I am trying to use Hibernate on my project << all sources if wanted, I try to create and save an object player on startup, I get the following error:

START SCRIPT!
org.hibernate.property.access.spi.PropertyAccessException: Error accessing field [private java.util.Date centaurus.domain.User.created] by reflection for persistent property [centaurus.domain.User#created] : User{id=0, email='test', created=Wed Jun 08 13:06:53 BST 2016}
    at org.hibernate.property.access.spi.GetterFieldImpl.get(GetterFieldImpl.java:43)
    at org.hibernate.property.access.spi.GetterFieldImpl.getForInsert(GetterFieldImpl.java:58)
    at org.hibernate.tuple.entity.AbstractEntityTuplizer.getPropertyValuesToInsert(AbstractEntityTuplizer.java:521)
    at org.hibernate.tuple.entity.PojoEntityTuplizer.getPropertyValuesToInsert(PojoEntityTuplizer.java:228)
    at org.hibernate.persister.entity.AbstractEntityPersister.getPropertyValuesToInsert(AbstractEntityPersister.java:4701)
    at org.hibernate.event.internal.AbstractSaveEventListener.performSaveOrReplicate(AbstractSaveEventListener.java:254)
    at org.hibernate.event.internal.AbstractSaveEventListener.performSave(AbstractSaveEventListener.java:182)
    at org.hibernate.event.internal.AbstractSaveEventListener.saveWithGeneratedId(AbstractSaveEventListener.java:113)
    at org.hibernate.event.internal.DefaultSaveOrUpdateEventListener.saveWithGeneratedOrRequestedId(DefaultSaveOrUpdateEventListener.java:192)
    at org.hibernate.event.internal.DefaultSaveEventListener.saveWithGeneratedOrRequestedId(DefaultSaveEventListener.java:38)
    at org.hibernate.event.internal.DefaultSaveOrUpdateEventListener.entityIsTransient(DefaultSaveOrUpdateEventListener.java:177)
    at org.hibernate.event.internal.DefaultSaveEventListener.performSaveOrUpdate(DefaultSaveEventListener.java:32)
    at org.hibernate.event.internal.DefaultSaveOrUpdateEventListener.onSaveOrUpdate(DefaultSaveOrUpdateEventListener.java:73)
    at org.hibernate.internal.SessionImpl.fireSave(SessionImpl.java:682)
    at org.hibernate.internal.SessionImpl.save(SessionImpl.java:674)
    at org.hibernate.internal.SessionImpl.save(SessionImpl.java:669)
    at centaurus.service.player.PlayerDAOimpl.saveUser(PlayerDAOimpl.java:32)
    at centaurus.Dbmaintain.start(Dbmaintain.java:25)
    at restx.factory.Factory.start(Factory.java:846)
    at restx.RestxMainRouterFactory.build(RestxMainRouterFactory.java:450)
    at restx.RestxMainRouterFactory.newInstance(RestxMainRouterFactory.java:70)
    at restx.servlet.RestxMainRouterServlet.init(RestxMainRouterServlet.java:74)
    at org.eclipse.jetty.servlet.ServletHolder.initServlet(ServletHolder.java:519)
    at org.eclipse.jetty.servlet.ServletHolder.doStart(ServletHolder.java:331)
    at org.eclipse.jetty.util.component.AbstractLifeCycle.start(AbstractLifeCycle.java:64)
    at org.eclipse.jetty.servlet.ServletHandler.initialize(ServletHandler.java:747)
    at org.eclipse.jetty.servlet.ServletContextHandler.startContext(ServletContextHandler.java:265)
    at org.eclipse.jetty.webapp.WebAppContext.startContext(WebAppContext.java:1250)
    at org.eclipse.jetty.server.handler.ContextHandler.doStart(ContextHandler.java:706)
    at org.eclipse.jetty.webapp.WebAppContext.doStart(WebAppContext.java:492)
    at org.eclipse.jetty.util.component.AbstractLifeCycle.start(AbstractLifeCycle.java:64)
    at org.eclipse.jetty.server.handler.HandlerCollection.doStart(HandlerCollection.java:229)
    at org.eclipse.jetty.util.component.AbstractLifeCycle.start(AbstractLifeCycle.java:64)
    at org.eclipse.jetty.server.handler.HandlerCollection.doStart(HandlerCollection.java:229)
    at org.eclipse.jetty.util.component.AbstractLifeCycle.start(AbstractLifeCycle.java:64)
    at org.eclipse.jetty.server.handler.HandlerWrapper.doStart(HandlerWrapper.java:95)
    at org.eclipse.jetty.server.Server.doStart(Server.java:277)
    at org.eclipse.jetty.util.component.AbstractLifeCycle.start(AbstractLifeCycle.java:64)
    at restx.server.JettyWebServer.start(JettyWebServer.java:109)
    at restx.server.JettyWebServer.startAndAwait(JettyWebServer.java:114)
    at centaurus.AppServer.main(AppServer.java:30)
Caused by: java.lang.IllegalArgumentException: Can not set java.util.Date field centaurus.domain.User.created to centaurus.domain.User
    at sun.reflect.UnsafeFieldAccessorImpl.throwSetIllegalArgumentException(UnsafeFieldAccessorImpl.java:164)
    at sun.reflect.UnsafeFieldAccessorImpl.throwSetIllegalArgumentException(UnsafeFieldAccessorImpl.java:168)
    at sun.reflect.UnsafeFieldAccessorImpl.ensureObj(UnsafeFieldAccessorImpl.java:55)
    at sun.reflect.UnsafeObjectFieldAccessorImpl.get(UnsafeObjectFieldAccessorImpl.java:36)
    at java.lang.reflect.Field.get(Field.java:379)
    at org.hibernate.property.access.spi.GetterFieldImpl.get(GetterFieldImpl.java:39)
    ... 40 more
2016-06-08 13:06:53,232 [main            ] [          ] INFO  restx.monitor.MetricsConfiguration - registering Metrics JVM metrics

I have stepped through my program and it seems to have a valid object passed the the hibernate save function, and somewhere inside it throws an error. I have tried removing the created field, at which point it then complains about a string field with the same error, trying to set it as a Player object itself.

here is my DAOimpl.class

package centaurus.dao.user;

import centaurus.domain.User;

import centaurus.service.HibernateUtils;
import restx.factory.Component;

import org.hibernate.HibernateException;
import org.hibernate.Session;
import org.hibernate.Transaction;

import javax.inject.Named;
import java.util.List;

@Component
public class UserDAOimpl implements UserDAO {
    private static HibernateUtils hibernateUtils;

    public UserDAOimpl(@Named("HibernateUtils") HibernateUtils hibernateUtils) {
        this.hibernateUtils = hibernateUtils;
    }

    public User saveUser(User user){
        Session session = hibernateUtils.getFactory().openSession();
        Transaction tx = null;
        Integer playerID = null;
        try{
            tx = session.beginTransaction();
            //playerID = (Integer) session.save(user);
            session.save(user);

            tx.commit();

        }catch (HibernateException e) {
            if (tx!=null) tx.rollback();
            e.printStackTrace();
        }finally {
            session.close();
        }
        return user;
    }

    public User getUser(int playerId){
        Session session = hibernateUtils.getFactory().openSession();
        try{
            User user = (User)session.get(User.class, playerId);
            return user;
        }catch (HibernateException e) {

        }finally {
            session.close();
        }
        return null;
    }

    public List<User> getUsers(){
        Session session = hibernateUtils.getFactory().openSession();
        List<User> list = null;
        try{
            list = session.createCriteria(User.class).list();

        }catch (HibernateException e) {

        }finally {
            session.close();
        }
        return list;
    }
}

I have googled and googled and tried as many hibernate tutorials as i can find and I still have this issue. I don't understand why hibernate is trying to set a field as an object, I have my annotations.

incase its wanted here is my domain object player:

package centaurus.domain;

import javax.persistence.*;
import java.io.Serializable;
import java.util.Calendar;
import java.util.Date;

@Entity
@Table(name="users")
public class User implements Serializable{

    @Id
    @GeneratedValue(strategy = GenerationType.IDENTITY)
    @Column(name="USER_ID")
    private int id = 0;

    @Column(name="EMAIL")
    private String email = "";

    @Column(name="CREATED")
    private Date created = null;

    public User(){
        Calendar cal = Calendar.getInstance();
        this.created = cal.getTime();
    };

    public User(int id, String email, Date created) {
        this.id = id;
        this.email = email;
        this.created = created;
    }

    public String getEmail() {
        return email;
    }

    public void setEmail(String email) {
        this.email = email;
    }

    public void setId(int id) {
        this.id = id;
    }

    public int getId() {
        return id;
    }

    public Date getCreated() {
        return created;
    }

    public void setCreated(Date created) {
        this.created = created;
    }

    @Override
    public String toString() {
        return "User{" +
                "id=" + id +
                ", email='" + email + '\'' +
                ", created=" + created +
                '}';
    }
} 

and here is the calling class:

package centaurus;

import centaurus.dao.user.UserDAO;
import centaurus.domain.User;
import restx.factory.AutoStartable;
import restx.factory.Component;

import javax.inject.Named;


@Component
public class DBMaintain implements AutoStartable{
    private UserDAO userDAO;

    public DBMaintain(@Named("UserDAOimpl") UserDAO userDAO) {
        this.userDAO = userDAO;
    }

    public void start(){
        System.out.println("START SCRIPT!");

        //test
        User p = new User();
        p.setEmail("test");
        userDAO.saveUser(p);

    }
}

Please does anyone know how to solve this issue, thanks.