Question

I have used maven plugin for hibernate and it has generated entity classes without identifing sequences that are related to ID fields, id fields are generated as BigDecimal… now even if I point to an existing sequence through code like..

@Entity
@javax.persistence.SequenceGenerator(

name = "SEQ_NATUREMASTER", sequenceName = "aop_teqachers_school_nature_id_seq")
@Table(name = "aop_teachers_school_nature_master", schema = "public", uniqueConstraints = @UniqueConstraint(columnNames = "school_nature"))
public class AopTeachersSchoolNatureMaster implements java.io.Serializable {

 /**
  * Above code is added after generating entity class
  */

 private BigDecimal id;

and I am getting error

INFO : aop.web.teacher.controller.SchoolMasterInsertController - Attemped saving!testnature
Hibernate: select nextval ('aop_teqachers_school_nature_id_seq')
Dec 14, 2010 6:57:26 PM org.apache.catalina.core.StandardWrapperValve invoke
SEVERE: Servlet.service() for servlet appServlet threw exception
org.hibernate.id.IdentifierGenerationException: this id generator generates long, integer, short or string
 at org.hibernate.id.IdentifierGeneratorHelper.get(IdentifierGeneratorHelper.java:123)
 at org.hibernate.id.SequenceGenerator.generate(SequenceGenerator.java:101)
 at org.hibernate.id.SequenceHiLoGenerator.generate(SequenceHiLoGenerator.java:81)
 at org.hibernate.event.def.AbstractSaveEventListener.saveWithGeneratedId(AbstractSaveEventListener.java:122)
 at org.hibernate.ejb.event.EJB3PersistEventListener.saveWithGeneratedId(EJB3PersistEventListener.java:69)
 at org.hibernate.event.def.DefaultPersistEventListener.entityIsTransient(DefaultPersistEventListener.java:154)
 at org.hibernate.event.def.DefaultPersistEventListener.onPersist(DefaultPersistEventListener.java:110)
 at org.hibernate.event.def.DefaultPersistEventListener.onPersist(DefaultPersistEventListener.java:61)
 at org.hibernate.impl.SessionImpl.firePersist(SessionImpl.java:650)
 at org.hibernate.impl.SessionImpl.persist(SessionImpl.java:624)
 at org.hibernate.impl.SessionImpl.persist(SessionImpl.java:628)
 at org.hibernate.ejb.AbstractEntityManagerImpl.persist(AbstractEntityManagerImpl.java:308)

Answer 1

I wouldn’t go for a decimal ID. And I really don’t think you’d need BigInteger either. So change it to int or long. (The reason this fails is that the sequence can’t generate the types BigX)