Can not set java.lang.Long field Event.idEvent to java.lang.Long

Question

I have a entity "Event" and when i want select a Event by id, i have this error : Can not set java.lang.Long Event.idEvent to java.lang.Long

javax.persistence.PersistenceException: org.hibernate.property.access.spi.PropertyAccessException: Error accessing field [private java.lang.Long Event.idEvent] by reflection for persistent property [Event#idEvent] : 1
    org.hibernate.internal.ExceptionConverterImpl.convert(ExceptionConverterImpl.java:154)
    org.hibernate.internal.ExceptionConverterImpl.convert(ExceptionConverterImpl.java:181)
    org.hibernate.query.internal.AbstractProducedQuery.list(AbstractProducedQuery.java:1538)
    org.hibernate.query.Query.getResultList(Query.java:165)
    fr.eni.sortircom.dal.dao.hibernate.HibernateRegistrationDAO.selectById(HibernateRegistrationDAO.java:19)
    fr.eni.sortircom.bll.RegistrationManager.selectParticipantEvent(RegistrationManager.java:27)
    fr.eni.sortircom.servlet.ShowEventServlet.doGet(ShowEventServlet.java:28)
    javax.servlet.http.HttpServlet.service(HttpServlet.java:635)
    javax.servlet.http.HttpServlet.service(HttpServlet.java:742)
    org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52)
cause mère

org.hibernate.property.access.spi.PropertyAccessException: Error accessing field [private java.lang.Long fr.eni.sortircom.bo.Event.idEvent] by reflection for persistent property [fr.eni.sortircom.bo.Event#idEvent] : 1
    org.hibernate.property.access.spi.GetterFieldImpl.get(GetterFieldImpl.java:75)
    org.hibernate.tuple.entity.AbstractEntityTuplizer.getIdentifier(AbstractEntityTuplizer.java:224)
    org.hibernate.persister.entity.AbstractEntityPersister.getIdentifier(AbstractEntityPersister.java:4940)
    org.hibernate.persister.entity.AbstractEntityPersister.isTransient(AbstractEntityPersister.java:4640)
    org.hibernate.engine.internal.ForeignKeys.isTransient(ForeignKeys.java:297)
    org.hibernate.engine.internal.ForeignKeys.getEntityIdentifierIfNotUnsaved(ForeignKeys.java:347)
    org.hibernate.type.EntityType.getIdentifier(EntityType.java:495)
    org.hibernate.type.EntityType.nullSafeSet(EntityType.java:288)
    org.hibernate.param.NamedParameterSpecification.bind(NamedParameterSpecification.java:53)
    org.hibernate.loader.hql.QueryLoader.bindParameterValues(QueryLoader.java:645)
    org.hibernate.loader.Loader.prepareQueryStatement(Loader.java:2006)
    org.hibernate.loader.Loader.executeQueryStatement(Loader.java:1920)
    org.hibernate.loader.Loader.executeQueryStatement(Loader.java:1898)
    org.hibernate.loader.Loader.doQuery(Loader.java:937)
    org.hibernate.loader.Loader.doQueryAndInitializeNonLazyCollections(Loader.java:340)
    org.hibernate.loader.Loader.doList(Loader.java:2695)
    org.hibernate.loader.Loader.doList(Loader.java:2678)
    org.hibernate.loader.Loader.listIgnoreQueryCache(Loader.java:2512)
    org.hibernate.loader.Loader.list(Loader.java:2507)
    org.hibernate.loader.hql.QueryLoader.list(QueryLoader.java:504)
    org.hibernate.hql.internal.ast.QueryTranslatorImpl.list(QueryTranslatorImpl.java:396)
    org.hibernate.engine.query.spi.HQLQueryPlan.performList(HQLQueryPlan.java:224)
    org.hibernate.internal.SessionImpl.list(SessionImpl.java:1538)
    org.hibernate.query.internal.AbstractProducedQuery.doList(AbstractProducedQuery.java:1561)
    org.hibernate.query.internal.AbstractProducedQuery.list(AbstractProducedQuery.java:1529)
    org.hibernate.query.Query.getResultList(Query.java:165)
    fr.eni.sortircom.dal.dao.hibernate.HibernateRegistrationDAO.selectById(HibernateRegistrationDAO.java:19)
    fr.eni.sortircom.bll.RegistrationManager.selectParticipantEvent(RegistrationManager.java:27)
    fr.eni.sortircom.servlet.ShowEventServlet.doGet(ShowEventServlet.java:28)
    javax.servlet.http.HttpServlet.service(HttpServlet.java:635)
    javax.servlet.http.HttpServlet.service(HttpServlet.java:742)
    org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52)
cause mère

java.lang.IllegalArgumentException: Can not set java.lang.Long field fr.eni.sortircom.bo.Event.idEvent to java.lang.Long
    sun.reflect.UnsafeFieldAccessorImpl.throwSetIllegalArgumentException(UnsafeFieldAccessorImpl.java:167)
    sun.reflect.UnsafeFieldAccessorImpl.throwSetIllegalArgumentException(UnsafeFieldAccessorImpl.java:171)
    sun.reflect.UnsafeFieldAccessorImpl.ensureObj(UnsafeFieldAccessorImpl.java:58)
    sun.reflect.UnsafeObjectFieldAccessorImpl.get(UnsafeObjectFieldAccessorImpl.java:36)
    java.lang.reflect.Field.get(Field.java:393)
    org.hibernate.property.access.spi.GetterFieldImpl.get(GetterFieldImpl.java:71)
    org.hibernate.tuple.entity.AbstractEntityTuplizer.getIdentifier(AbstractEntityTuplizer.java:224)
    org.hibernate.persister.entity.AbstractEntityPersister.getIdentifier(AbstractEntityPersister.java:4940)
    org.hibernate.persister.entity.AbstractEntityPersister.isTransient(AbstractEntityPersister.java:4640)
    org.hibernate.engine.internal.ForeignKeys.isTransient(ForeignKeys.java:297)
    org.hibernate.engine.internal.ForeignKeys.getEntityIdentifierIfNotUnsaved(ForeignKeys.java:347)
    org.hibernate.type.EntityType.getIdentifier(EntityType.java:495)
    org.hibernate.type.EntityType.nullSafeSet(EntityType.java:288)
    org.hibernate.param.NamedParameterSpecification.bind(NamedParameterSpecification.java:53)
    org.hibernate.loader.hql.QueryLoader.bindParameterValues(QueryLoader.java:645)
    org.hibernate.loader.Loader.prepareQueryStatement(Loader.java:2006)
    org.hibernate.loader.Loader.executeQueryStatement(Loader.java:1920)
    org.hibernate.loader.Loader.executeQueryStatement(Loader.java:1898)
    org.hibernate.loader.Loader.doQuery(Loader.java:937)
    org.hibernate.loader.Loader.doQueryAndInitializeNonLazyCollections(Loader.java:340)
    org.hibernate.loader.Loader.doList(Loader.java:2695)
    org.hibernate.loader.Loader.doList(Loader.java:2678)
    org.hibernate.loader.Loader.listIgnoreQueryCache(Loader.java:2512)
    org.hibernate.loader.Loader.list(Loader.java:2507)
    org.hibernate.loader.hql.QueryLoader.list(QueryLoader.java:504)
    org.hibernate.hql.internal.ast.QueryTranslatorImpl.list(QueryTranslatorImpl.java:396)
    org.hibernate.engine.query.spi.HQLQueryPlan.performList(HQLQueryPlan.java:224)
    org.hibernate.internal.SessionImpl.list(SessionImpl.java:1538)
    org.hibernate.query.internal.AbstractProducedQuery.doList(AbstractProducedQuery.java:1561)
    org.hibernate.query.internal.AbstractProducedQuery.list(AbstractProducedQuery.java:1529)
    org.hibernate.query.Query.getResultList(Query.java:165)
    fr.eni.sortircom.dal.dao.hibernate.HibernateRegistrationDAO.selectById(HibernateRegistrationDAO.java:19)
    fr.eni.sortircom.bll.RegistrationManager.selectParticipantEvent(RegistrationManager.java:27)
    fr.eni.sortircom.servlet.ShowEventServlet.doGet(ShowEventServlet.java:28)
    javax.servlet.http.HttpServlet.service(HttpServlet.java:635)
    javax.servlet.http.HttpServlet.service(HttpServlet.java:742)
    org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52)

here is my entity Event :

public class Event implements Serializable {

    @Id
    @GeneratedValue(strategy = GenerationType.IDENTITY)
    @Column(name = "id_event")
    private Long idEvent;

and here the select by id :

 public Event selectById(Long id) {
        Session session = ConnectionProvider.getConnection();
        Query q = session.createQuery("FROM Event WHERE idEvent=:id");
        q.setParameter("id", id);
        List<Event> events = q.getResultList();
        Event event = events.get(0);
        return event;
    }

I have check the Long and he is correct. And i have the same request for a another Entity, and it works. I do not understand.

Thank for your help.

Answer 1

Not sure if this will actually help, but seems like you've chosen very complex way. You can simply implement CrudRepository<Event, Long> interface with your repository and do the select using its findById method.

This is actually really easy, just follow those simple steps.

I. Implement the CrudRepository.

public interface EventRepository implements CrudRepository<Event, Long> {}

II. Use findById method in your service with EventRepository autowired.

Long id  = ...;
Optional<Event> event = eventRepository.findById(id);

Answer 2

You have a mismatch in your parameters i.e you try and specify a Long as the parameter for a User type:

You change it in one of two ways: I have added This is with one sample example .

@Query("DELETE FROM Collaborator c WHERE c.user.id = :userId AND c.task.id =:taskId")
void deleteUserFromTask(@Param("userId") Long userId, @Param("taskId") Long taskId);

or

@Query("DELETE FROM Collaborator c WHERE c.user = :user AND c.task = :task")
void deleteUserFromTask(@Param("user") User user, @Param("task") Task task);

Thanks.