[appengine-java] persistence with JPA

[Johan Vallejo]

Hi I am new in the list, in these days i am trying save data between two entity beans using JPA but without success, i am cheking the log nd says: Uncaught exception from servlet javax.persistence.PersistenceException: Error in meta-data for beans.distritos.id: Cannot have a java.lang.Long primary key and be a child object (owning field is beans.evento.distrito). this is my servlet:             Long id = Long.parseLong(request.getParameter("idDistrito"));             response.setContentType("text/html");             EntityManager cn = emf.get().createEntityManager();             Query q = cn.createQuery("SELECT d FROM distritos d WHERE d.id = :codigo");             q.setParameter("codigo",id);             distritos dist = (distritos) q.getSingleResult();             EntityManager cn2 = emf.get().createEntityManager();             cn2.getTransaction().begin();             evento e = new evento();                   e.setDistrito(dist);             Date fecha = new Date();             e.setFechaCreacion(fecha);             try{                 cn2.persist(e);                 response.getWriter().write("ok");             }finally{                 cn2.getTransaction().commit();                 cn2.close();             } this is my entity bean Evento: @Entity public class evento implements Serializable {     @Id     @GeneratedValue(strategy = GenerationType.IDENTITY)     Long id;     @Temporal(javax.persistence.TemporalType.DATE)     private Date fechaCreacion;     @JoinColumn     @OneToMany(cascade = CascadeType.ALL)     private distritos distrito;    --getter and setter-- Distrito: @Entity public class distritos implements Serializable {     @Id     @GeneratedValue(strategy = GenerationType.IDENTITY)     Long id;     private String distrito;         --getter and setter-- i hope anyone help me, Thank! -- You received this message because you are subscribed to the Google Groups "Google App Engine for Java" group. To post to this group, send email to google-appengine-j...@googlegroups.com. To unsubscribe from this group, send email to google-appengine-java+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/google-appengine-java?hl=en.