[JPA_SPEC-42] Allow null @Embedded Objects Created: 17/Jan/13  Updated: 05/Dec/16

Status: Open
Project: jpa-spec
Component/s: None
Affects Version/s: None
Fix Version/s: None

Type: Improvement Priority: Minor
Reporter: reza_rahman Assignee: ldemichiel
Resolution: Unresolved Votes: 4
Labels: None
Remaining Estimate: Not Specified
Time Spent: Not Specified
Original Estimate: Not Specified


 Description   

At the moment, it is not possible to have null @Embedded objects in JPA (while Hibernate, etc allow it). This is quite a common scenario in most domain models that JPA should take into account. The following is an example:

<pre>
public class Employee {
...
@Embedded(optional=true) // This should be possible since the employee entity can be null in some
// stages of it's life-cycle
private Address address;
...
}
</pre>



 Comments   
Comment by neilstockton [ 05/Dec/16 ]

Just using "optional" doesn't define how a JPA provider can distinguish between a NULL embedded object and an embedded object with null fields.

The JDO spec provided a definition for this problem.

"null-indicator-column" defines which column used by the embedded object is for determining a null object, and "null-indicator-value" defines the value in that column that means we have a null object. So then the JPA provider can persist this null value in the null column on persist of a null embedded object, and ditto when retrieving.

Generated at Sun Mar 26 01:22:47 UTC 2017 using JIRA 6.2.3#6260-sha1:63ef1d6dac3f4f4d7db4c1effd405ba38ccdc558.