ManyToOne ClassCastException

Question

I am trying to create a "simple" OneToMany and ManyToOne relation. And I get following Exception:

Caused by: java.lang.ClassCastException: org.hibernate.mapping.ManyToOne cannot be cast to org.hibernate.mapping.Component at org.hibernate.mapping.PersistentClass.getRecursiveProperty(PersistentClass.java:464) ~[hibernate-core-5.0.9.Final.jar:5.0.9.Final] at org.hibernate.mapping.PersistentClass.getRecursiveProperty(PersistentClass.java:420) ~[hibernate-core-5.0.9.Final.jar:5.0.9.Final] at org.hibernate.cfg.annotations.CollectionBinder.bindStarToManySecondPass(CollectionBinder.java:758) ~[hibernate-core-5.0.9.Final.jar:5.0.9.Final] at org.hibernate.cfg.annotations.CollectionBinder$1.secondPass(CollectionBinder.java:719) ~[hibernate-core-5.0.9.Final.jar:5.0.9.Final] at org.hibernate.cfg.CollectionSecondPass.doSecondPass(CollectionSecondPass.java:54) ~[hibernate-core-5.0.9.Final.jar:5.0.9.Final] at org.hibernate.boot.internal.InFlightMetadataCollectorImpl.processSecondPasses(InFlightMetadataCollectorImpl.java:1655) ~[hibernate-core-5.0.9.Final.jar:5.0.9.Final] at org.hibernate.boot.internal.InFlightMetadataCollectorImpl.processSecondPasses(InFlightMetadataCollectorImpl.java:1623) ~[hibernate-core-5.0.9.Final.jar:5.0.9.Final] at org.hibernate.boot.model.process.spi.MetadataBuildingProcess.complete(MetadataBuildingProcess.java:278) ~[hibernate-core-5.0.9.Final.jar:5.0.9.Final] at org.hibernate.jpa.boot.internal.EntityManagerFactoryBuilderImpl.metadata(EntityManagerFactoryBuilderImpl.java:847) ~[hibernate-entitymanager-5.0.9.Final.jar:5.0.9.Final] at org.hibernate.jpa.boot.internal.EntityManagerFactoryBuilderImpl.build(EntityManagerFactoryBuilderImpl.java:874) ~[hibernate-entitymanager-5.0.9.Final.jar:5.0.9.Final] at org.springframework.orm.jpa.vendor.SpringHibernateJpaPersistenceProvider.createContainerEntityManagerFactory(SpringHibernateJpaPersistenceProvider.java:60) ~[spring-orm-4.3.2.RELEASE.jar:4.3.2.RELEASE] at org.springframework.orm.jpa.LocalContainerEntityManagerFactoryBean.createNativeEntityManagerFactory(LocalContainerEntityManagerFactoryBean.java:338) ~[spring-orm-4.3.2.RELEASE.jar:4.3.2.RELEASE] at org.springframework.orm.jpa.AbstractEntityManagerFactoryBean.buildNativeEntityManagerFactory(AbstractEntityManagerFactoryBean.java:373) ~[spring-orm-4.3.2.RELEASE.jar:4.3.2.RELEASE] at org.springframework.orm.jpa.AbstractEntityManagerFactoryBean.afterPropertiesSet(AbstractEntityManagerFactoryBean.java:362) ~[spring-orm-4.3.2.RELEASE.jar:4.3.2.RELEASE] at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.invokeInitMethods(AbstractAutowireCapableBeanFactory.java:1637) ~[spring-beans-4.3.2.RELEASE.jar:4.3.2.RELEASE] at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.initializeBean(AbstractAutowireCapableBeanFactory.java:1574) ~[spring-beans-4.3.2.RELEASE.jar:4.3.2.RELEASE] ... 39 common frames omitted

Is someone able to tell me what I am doing wrong?

Below you can find my two entities.

Thank you in advanced.

  import javax.persistence.OneToMany;
@Entity
@Table(uniqueConstraints={@UniqueConstraint(columnNames={"questionGroupID","questionID"})})
public class QuestionGroupEntity implements Serializable{

    private static final long serialVersionUID = 1796640204447018439L;

    @Id
    @NotEmpty
    @Column(name="question_group_id")
    private String questionGroupID;

    @NotEmpty
    private String label;


    @NotEmpty
    private String questionID;


    @OneToMany(fetch=FetchType.EAGER,targetEntity=QuestionGroupMappingEntity.class,mappedBy="questionGroup")
    List<QuestionGroupMappingEntity> questionGroupMappings;

AND

import javax.persistence.ManyToOne;
    @Entity
    @Table(uniqueConstraints={@UniqueConstraint(columnNames={"questionGroupID","questionID","answerID"})})
    public class QuestionGroupMappingEntity implements Serializable {

        private static final long serialVersionUID = 8437546139229082305L;

        @Id
        @SequenceGenerator(name="groupMappingIDGenerator")
        @GeneratedValue(generator="groupMappingIDGenerator",strategy=GenerationType.AUTO)
        private String groupMappingID;

        @NotEmpty
        private String questionID;

        @NotEmpty
        private String questionGroupID;

        @NotEmpty
        private String answerID;

        @ManyToOne(fetch=FetchType.EAGER)
        @JoinColumn(name="question_group_id")
        private QuestionGroupEntity questionGroup;

have you defined the getters and setters? On what call are you getting the error? — george

DCO DCO · Accepted Answer · 2016-09-06T06:52:52

Thank you for your answers. I solved this issue by adding those properties spring.jpa.hibernate.ddl-auto=update spring.jpa.generate-ddl=true The problem was that spring-data was not able to update the schema.

ManyToOne ClassCastException

2 Answers