ADF BC : polymorphic activation issue

Question

hi
Please consider this example application created using JDeveloper 10.1.3.4.0
at http://www.consideringred.com/files/oracle/2010/PolymorphicActivationIssue10gApp-v0.01.zip
It has Entity Objects AdPresEmployees and ItProgEmployees that extend the Employees Entity Object (based on HR.EMPLOYEES).
There is also the View Object EmployeesVO that is based on Employees and its sub-types AdPresEmployees and ItProgEmployees.
The basic scenario (sc1) for the expected behaviour goes like
- (sc1-a) run createEmployees.jspx
- (sc1-b) enter "20" for "create_pEmployeeId" and "20email" for "create_pEmail" and click the "createAdPresEmployees" button, resulting in a new AdPresEmployeesImpl based row in the table
- (sc1-c) enter "21" for "create_pEmployeeId" and "21email" for "create_pEmail" and click the "createItProgEmployees" button, resulting in a new ItProgEmployeesImpl based row in the table
To reproduce scenario (sc1) it is important to not have the system property "jbo.ampool.doampooling" configured to get the default Application Module pooling behaviour, and to have "-Ddopolymorphicactivationfix=false" (or not configured), to result in two new rows in the table as can be seen in the screenshot PAI-sc1-doPooling-noFix.png.
To reproduce the problem in a scenario (sc2) with the same steps as (sc1) but with "-Djbo.ampool.doampooling=false" configured to avoid Application Module pooling and force passivation and activation, still "-Ddopolymorphicactivationfix=false", the result for a step (sc2-c) would be "JBO-27027: Missing mandatory attributes for a row with key ..." and several "JBO-27014: Attribute ... is required" messages as can be seen in the screenshot PAI-sc2-noPooling-noFix.png.
Maybe the problem in scenario (sc2) is related to bug 9495116, "PROBLEM WITH ACTIVATION PASSIVATION MAKING USE OF POLYMORPHISM ENTITIES ...".
After some debugging, to try and work around this problem I have overridden the method findByPrimaryKey() in a custom Entity Definition class like this, conditionally calling findByPKExtended()
public class EmployeesDefImpl
     extends EntityDefImpl
     public EntityImpl findByPrimaryKey(DBTransaction pDBTransaction, Key pKey)
          if ("true".equals(System.getProperty("dopolymorphicactivationfix"))
               && isCalledFromActivateNewRowTrackerMethod())
               return super.findByPKExtended(pDBTransaction, pKey, true);
          return super.findByPrimaryKey(pDBTransaction, pKey);
}So, a scenario (sc3) similar to (sc1) with default Application Module pooling but with "-Ddopolymorphicactivationfix=true" still behaves the same as (sc1), resulting in two new rows in the table as can be seen in the screenshot PAI-sc3-doPooling-doFix.png.
But, also a scenario (sc4) with "-Djbo.ampool.doampooling=false", so no pooling, and "-Ddopolymorphicactivationfix=true", now behaves as expected, see screenshot PAI-sc4-noPooling-doFix.png.
questions:
- (q1) Is there a real solution for the polymorphic activation problem in scenario (sc2)?
- (q2) Is the workaround in scenario (sc4) a valid workaround, or how can it be improved?
many thanks
Jan Vervecken

Answer 1

fyi
This looks like it could be related to the blog post from Dimitrios Stassinopoulos, "Entity Inheritance And Passivation-Activation Possible Problem in ADF 11g ",
at http://dstas.blogspot.com/2010/11/entity-inheritance-and-passivation.html
regards
Jan