JPA and hibernate Problem with InheritanceType.SINGLE_TABLE

srigold · **Joined:** Mon Nov 29, 2004 5:34 pm **Posts:** 35

Hi,
I am trying to figure this error and I have already spend lot of time, Please help me in this.

I have Action class, which looks like this

Code:

@Entity
@Table(name = "BATCH_ACTION")
@Inheritance(strategy = InheritanceType.SINGLE_TABLE)
@DiscriminatorColumn(name = "ACTN_TYPE", discriminatorType = DiscriminatorType.INTEGER)

public class Action extends BaseObject
{

}

And the subclass which is extends the Action class

Code:

@Entity
@DiscriminatorValue("3")
public class ExtractCompletedAction extends Action
{
}

In my business layer of code, I was creating new action.

Code:

Action newAction = new Action();

And setting all the required attributes.

And when I retrieve the batch object from database using hibernate createCriteria every thing looks good. It also get the actions based on the discriminator column value. In the above case all having value 3

Problem/Issue
When I try to save the object new action, the type (ACTN_TYPE used on Discriminator column) has value = 1955883606 in the database.
I was expecting 3 (Since that was there in my DiscriminatorValue value)

maciejziaja · **Joined:** Thu May 17, 2007 9:49 am **Posts:** 9

Discriminator with value 3 is binded with ExtractCompletedAction entity. I think you should create it like that:

Code:

Action newAction = new ExtractCompletedAction();

srigold · **Joined:** Mon Nov 29, 2004 5:34 pm **Posts:** 35

Hi,
Thanks for quick reply, I tried different options and this was were I was stuck.
I tried before and I changed the code now as you said. I got following error.

Quote:

newAction = new ExtractStartedAction("EXTRACT_STARTED");

Code:

org.springframework.orm.hibernate3.HibernateSystemException: Unknown entity: com.xxx.abc.model.ExtractSkippedAction; nested exception is org.hibernate.MappingException: Unknown entity: com.xxx.abc.model.ExtractSkippedAction

Please let me know, any other thought in resolving this error.

srigold · **Joined:** Mon Nov 29, 2004 5:34 pm **Posts:** 35

I have solved my problem.

I have the super class

Code:

@Entity
@Table(name = "BATCH_ACTION")
@Inheritance(strategy = InheritanceType.SINGLE_TABLE)
@DiscriminatorColumn(name = "ACTN_TYPE", discriminatorType = DiscriminatorType.INTEGER)
public class Action extends BaseObject
{

}

and other sub class

Code:

@Entity
@DiscriminatorValue("3")
public class ExtractCompletedAction extends Action
{
}

I added all the sub classes in hibernate.hbm.xml file, then it worked.