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From Aitor Iturriondobeitia <laudio.i...@gmail.com>
Subject Re: my fist openjpa porject / problem. help me please
Date Fri, 22 Feb 2013 09:01:38 GMT
thanks for your answer?
i am new in this (JPA) and reading your answer i think that i am missing
somethig.
reading your answer i think that into my code there is some thing missing.
Can you help me please for geting my first example?

my classes are in https://dl.dropbox.com/u/3576658/Public.7z (2kb) and i
only have this:

1.- generic interface:
public interface IGenericDao<K, E> {
void persist(E entity);
}
2.- other interface, my interface.
public interface IWsSrvTrackRequest extends IGenericDao<Integer,
Wssrvtrackrequest>{
void wsSrvRequestPersist(Wssrvtrackrequest request);
}
3.- generic JPA-DAO:
public abstract class JpaDao<K, E> implements IGenericDao<K, E> {
protected Class<E> entityClass;

@PersistenceContext
protected EntityManager entityManager;

public JpaDao() {
ParameterizedType genericSuperclass = (ParameterizedType)
getClass().getGenericSuperclass();
this.entityClass = (Class<E>) genericSuperclass.getActualTypeArguments()[1];
}
public void persist(E entity) {
entityManager.persist(entity);
}
}
}
4.- my jpa-dao implementation (the Wssrvtrackrequest obj is one jpa object
(entity)).
public class JpaWsSrvTrackRequestDaoImpl extends JpaDao<Integer,
Wssrvtrackrequest> implements IWsSrvTrackRequest {
public void wsSrvRequestPersist(Wssrvtrackrequest request){
entityManager.persist(request);
}
}
i am make one main class:
public static void main(String[] args) {
IWsSrvTrackRequest r = new JpaWsSrvTrackRequestDaoImpl();
Wssrvtrackrequest v = new Wssrvtrackrequest();
v.setWssrvreqIp("la ip");
v.setWssrvreqOid("oid");
v.setWssrvreqOiduser("oiduser");
v.setWssrvreqRequest("la request");
r.persist(v);
}


Can you help me please.
I cannot get started


2013/2/20 Rick Curtis <curtisr7@gmail.com>

> Where is your EntityManager reference coming from? If you're using
> injection, I'd suggest looking through the logs for any error / warning
> messages that would help you figure out what is going on.
>
>
> On Wed, Feb 20, 2013 at 1:50 AM, Aitor Iturriondobeitia <
> laudio.info@gmail.com> wrote:
>
> > this:
> > public void persist(E entity) {
> >  entityManager.persist(entity); ** this line
> > }
> >
> > thanks for your answer
> >
> >
> > 2013/2/20 Rick Curtis <curtisr7@gmail.com>
> >
> > > What is at com.caf.db.dao.JpaDao.persist(JpaDao.java:20)?
> > >
> > >
> > > On Tue, Feb 19, 2013 at 5:08 PM, Aitor Iturriondobeitia <
> > > laudio.info@gmail.com> wrote:
> > >
> > > > hello
> > > > i an tring to build my firts openjpa app
> > > > i am readint this article (
> > > > http://java.dzone.com/articles/jpa-implementation-patterns) and
> > building
> > > > it
> > > > for this i make this:
> > > > 1.- generic interface:
> > > > public interface IGenericDao<K, E> {
> > > >  void persist(E entity);
> > > > }
> > > > 2.- other interface, my interface.
> > > > public interface IWsSrvTrackRequest  extends IGenericDao<Integer,
> > > > Wssrvtrackrequest>{
> > > >  void wsSrvRequestPersist(Wssrvtrackrequest request);
> > > > }
> > > > 3.- generic JPA-DAO:
> > > > public abstract class JpaDao<K, E> implements IGenericDao<K,
E> {
> > > >  protected Class<E> entityClass;
> > > >
> > > >  @PersistenceContext
> > > >  protected EntityManager entityManager;
> > > >
> > > >  public JpaDao() {
> > > >   ParameterizedType genericSuperclass = (ParameterizedType)
> > > > getClass().getGenericSuperclass();
> > > >   this.entityClass = (Class<E>)
> > > > genericSuperclass.getActualTypeArguments()[1];
> > > >  }
> > > >  public void persist(E entity) {
> > > >   entityManager.persist(entity);
> > > >  }
> > > >  }
> > > > }
> > > > 4.- my jpa-dao implementation (the Wssrvtrackrequest obj is one jpa
> > > object
> > > > (entity)).
> > > > public class JpaWsSrvTrackRequestDaoImpl extends JpaDao<Integer,
> > > > Wssrvtrackrequest> implements IWsSrvTrackRequest {
> > > >  public void wsSrvRequestPersist(Wssrvtrackrequest request){
> > > >    entityManager.persist(request);
> > > >  }
> > > > }
> > > > i am make one main class:
> > > > public static void main(String[] args) {
> > > >   IWsSrvTrackRequest r = new JpaWsSrvTrackRequestDaoImpl();
> > > >   Wssrvtrackrequest v = new Wssrvtrackrequest();
> > > >   v.setWssrvreqIp("la ip");
> > > >   v.setWssrvreqOid("oid");
> > > >   v.setWssrvreqOiduser("oiduser");
> > > >   v.setWssrvreqRequest("la request");
> > > >   r.persist(v);
> > > >  }
> > > >
> > > >  but it always returns one nullpointerexception.
> > > >  Exception in thread "main" java.lang.NullPointerException
> > > >  at com.caf.db.dao.JpaDao.persist(JpaDao.java:20)
> > > >  at com.caf.db.dao.ll.main(ll.java:20)
> > > >
> > > >  Can you help me please?
> > > >
> > > >  thanks
> > > >
> > >
> > >
> > >
> > > --
> > > *Rick Curtis*
> > >
> >
>
>
>
> --
> *Rick Curtis*
>

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