Hibernate - IllegalArgumentException model getter call occurred

Question

I am getting this error with my hibernation model and I cannot figure out what is 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 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 this might be a problem related to my JOINED inheritance, but I am getting the same error with TABLE_PER_CLASS . Do you see something that I did wrong?

Answer 1

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(); 

Answer 2

Make sure the table is of the same type as Idtag. What is an error report: type of mismatch with Integer.

Answer 3

Are these methods named according to bean naming conventions? I would say no.

Try setIdTag () and getIdTag ().

 @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; }