I'm getting this error with my hibernate model, and I can't figure out what's wrong.
Tag.java:
@Entity
@Table(name = "tag")
public class Tag implements java.io.Serializable {
private Integer idTag;
private String name;
private Set<Question> questions = new HashSet<Question>(0);
@Id
@GeneratedValue(strategy = IDENTITY)
@Column(name = "idtag", unique = true, nullable = false)
public Integer getIdTag() {
return this.idTag;
}
public void setIdTag(Integer idtag) {
this.idTag = idtag;
}
[...]
@OneToMany(fetch = FetchType.LAZY, mappedBy = "tag")
public Set<Question> getQuestions() {
return this.questions;
}
public void setQuestions(Set<Question> questions) {
this.questions = questions;
}
}
Question.java:
@Entity
@Table(name = "question")
@Inheritance(strategy=InheritanceType.JOINED)
public class Question implements java.io.Serializable {
protected Integer idQuestion;
protected Tag tag;
@Id
@GeneratedValue(strategy = IDENTITY)
@Column(name = "idquestion", unique = true, nullable = false)
public Integer getIdQuestion() {
return this.idQuestion;
}
public void setIdQuestion(Integer idquestion) {
this.idQuestion = idquestion;
}
@ManyToOne(fetch = FetchType.LAZY)
@JoinColumn(name = "idtag")
public Tag getTag() {
return this.tag;
}
public void setTag(Tag tag) {
this.tag = tag;
}
[...]
}
QuestionText.java:
@Entity
@Table(name = "question_text")
@PrimaryKeyJoinColumn(name="idquestion")
public class QuestionText extends Question implements java.io.Serializable {
[...]
}
And here is when this error appears (on query.list()
):
q = "FROM QuestionText WHERE tag = :tag";
query = (Query) session.createQuery(q);
query.setParameter("tag", tag);
List<Question> data = query.list();
Stacktrace:
org.hibernate.PropertyAccessException: IllegalArgumentException occurred calling getter of model.Tag.idtag
org.hibernate.property.BasicPropertyAccessor$BasicGetter.get(BasicPropertyAccessor.java:187)
org.hibernate.tuple.entity.AbstractEntityTuplizer.getIdentifier(AbstractEntityTuplizer.java:344)
org.hibernate.persister.entity.AbstractEntityPersister.getIdentifier(AbstractEntityPersister.java:4537)
org.hibernate.persister.entity.AbstractEntityPersister.isTransient(AbstractEntityPersister.java:4259)
org.hibernate.engine.internal.ForeignKeys.isTransient(ForeignKeys.java:209)
org.hibernate.engine.internal.ForeignKeys.getEntityIdentifierIfNotUnsaved(ForeignKeys.java:248)
org.hibernate.type.EntityType.getIdentifier(EntityType.java:510)
org.hibernate.type.ManyToOneType.nullSafeSet(ManyToOneType.java:174)
org.hibernate.param.NamedParameterSpecification.bind(NamedParameterSpecification.java:66)
org.hibernate.loader.hql.QueryLoader.bindParameterValues(QueryLoader.java:612)
org.hibernate.loader.Loader.prepareQueryStatement(Loader.java:1875)
org.hibernate.loader.Loader.executeQueryStatement(Loader.java:1836)
org.hibernate.loader.Loader.executeQueryStatement(Loader.java:1816)
org.hibernate.loader.Loader.doQuery(Loader.java:900)
org.hibernate.loader.Loader.doQueryAndInitializeNonLazyCollections(Loader.java:342)
org.hibernate.loader.Loader.doList(Loader.java:2526)
org.hibernate.loader.Loader.doList(Loader.java:2512)
org.hibernate.loader.Loader.listIgnoreQueryCache(Loader.java:2342)
org.hibernate.loader.Loader.list(Loader.java:2337)
org.hibernate.loader.hql.QueryLoader.list(QueryLoader.java:495)
org.hibernate.hql.internal.ast.QueryTranslatorImpl.list(QueryTranslatorImpl.java:357)
org.hibernate.engine.query.spi.HQLQueryPlan.performList(HQLQueryPlan.java:195)
org.hibernate.internal.SessionImpl.list(SessionImpl.java:1269)
org.hibernate.internal.QueryImpl.list(QueryImpl.java:101)
my.project.service.QuestionService.findCatItems(QuestionService.java:34)
I thought it might be an issue related to my JOINED
inheritance, but I get the same error with TABLE_PER_CLASS
. Do you see anything which I did wrong in this ?
Try this way
Tag tag = tagDAO.findTagbyId(1);
q = "FROM QuestionText qt WHERE qt.tag = :tag";
query = (Query) session.createQuery(q);
query.setParameter("tag", tag);
List<QuestionText> data = query.list();