使用休眠实体管理器更新实体

Question

I have one implementation where my entity Company extends RootEntity with

strategy =InheritanceType.JOINED.(I am using hibernate-entitymanager) 

I have other entities which does not extends RootEntity . When I create all entites it does create.But when I try to update an extended entity of RootEntity ,it does not update. But the non extending entity is updating. The update code is in GenericDaoImpl so it is the same update method.

what can be the problem? my code is:

@Transactional(value="tx")
public E update(E entity) {
    E merged = null;
    RootEntity baseEntity = null;
    if(entity instanceof RootEntity ){
        baseEntity = (RootEntity)entity;
        merged = entityManager.find(entityClass, baseEntity.getId());
    }
    merged = entityManager.merge(entity);
    entityManager.flush();
    return merged;
}

My Object That I am trying to merge:

public class Societa extends RootEntity implements Serializable{

     private static final long serialVersionUID = 1L;

     // ASSOCIAZIONE CAMPI DB VARIABILI NELLA CLASSE
     @Column(name="nomeSocieta",nullable = false,columnDefinition="CHAR(80)")
     private String nomeSocieta;

      ......
}

and my RootEntity is:

@Entity
@Inheritance(strategy =InheritanceType.JOINED)
    public class RootEntity {

       private static final long serialVersionUID = 1L;

       @Id
       @Column(name="id",nullable = false)
       @GeneratedValue(strategy = GenerationType.IDENTITY)
       private Long id;
        ...getters/setters..
   }

Answer 1

Newaz, I need to see your RootEntity and Company entity.

Also, I was having hard time understanding your provided code though -

1. Why you need that "if" condition? and what will happen if that if is not true?
2. entityManager.flush(); you don't have to do this, if i understand correctly, you are using spring and @Transactional automatically closes/flushes transaction when invoked method is finished.