How to use task flow's transaction options with session's user data

Question

Hi.
I have custom extension of ApplicationModuleImpl class:
package test.model
imports...
public class CustomAppModuleImpl extends ApplicationModuleImpl {
    public static final String SESSION_VAR = "MySessionVar";
    public CustomAppModuleImpl() {
        super();
    @Override
    protected void prepareSession(Session session) {
        super.prepareSession(session);
        System.out.println("######## " + this.getClass().getName() + ".prepareSession() called.  AM isRoot() = " + isRoot());
        Hashtable userData = session.getUserData();
        if (userData == null) {
            userData = new Hashtable();
        userData.put(SESSION_VAR, "Useless");
    @Override
    protected void create() {
        super.create();
        System.out.println("######## " + this.getClass().getName() + ".prepareSession() called.  AM isRoot() = " + isRoot());
}Inside userData I store some useful session-based values (here is just an example ;) ).
Within Model.jpr I defined that every Application Module I create must extends this CustomAppModuleImpl :
   <value n="oracle.jbo.extends.appModule" v="test.model.CustomAppModuleImpl"/>
...I have one AM with one view:
package test.model;
import oracle.jbo.server.ViewObjectImpl;
// ---    File generated by Oracle ADF Business Components Design Time.
// ---    Wed Mar 07 20:22:11 CET 2012
// ---    Custom code may be added to this class.
// ---    Warning: Do not modify method signatures of generated methods.
public class AppModule1Impl extends CustomAppModuleImpl {
     * This is the default constructor (do not remove).
    public AppModule1Impl() {
     * Container's getter for EmployeesView1.
     * @return EmployeesView1
    public ViewObjectImpl getEmployeesView1() {
        return (ViewObjectImpl)findViewObject("EmployeesView1");
}Now I have BTF (bounded task flow, with default properties) and I call that task flow on a button press. With default properties ( Transaction: <No Controller Transaction> ) I get preferred values from session's userData within Entity Object.
Code snippet inside that entity implementation looks like:
        DBTransaction dbt = getDBTransaction();
        System.out.println(getClass().getName() + " entity lives AM: " + dbt.getRootApplicationModule().getClass().getName());
        if (dbt.getSession().getUserData() == null) {
            System.out.println(CustomAppModuleImpl.SESSION_VAR + " -> NULL");
        } else {
            System.out.println(CustomAppModuleImpl.SESSION_VAR + " -> " + dbt.getSession().getUserData().get(CustomAppModuleImpl.SESSION_VAR));
...And as I mentioned output is correct:
test.model.EmployeesImpl entity lives AM: test.model.AppModule1Impl
MySessionVar -> UselessNow the trickiest part. As soon as I change property of called task flow Transaction to something else that +<No Controller Transaction>+, e.g. Always Begin New Transaction, code snippet from task-flow.xml :
    <transaction>
      <new-transaction/>
    </transaction>
..This session stuff begin to act unpredictably. Session's userData is now null. And Output looks like:
test.model.EmployeesImpl entity lives AM: oracle.jbo.server.ApplicationModuleImpl
MySessionVar -> NULLWhy in the world ADF uses oracle.jbo.server.ApplicationModuleImpl instead of test.model.AppModule1Impl or at least my defined test.model.CustomAppModuleImpl ?!?
Is this a bug? Or maybe a feature?
10x
Regards

Answer 1

Hi,
Why in the world ADF uses oracle.jbo.server.ApplicationModuleImpl instead of test.model.AppModule1Impl or at least my defined test.model.CustomAppModuleImpl ?!?
Is this a bug? Or maybe a feature?
ADF BC alwyas has a transaction opened even if the ADFc setting is No Transaction. So if you explicitly ask for a new transaction I assume that the ADF BC data control creates a new transaction without re-executing your AM initialization codes. Looks as if it uses an internal AM instance for this just to hold the transaction. However, worth filing this as a bug - assuming you reproduced this with a later version of either JDeveloper 11g R1 or R2
Frank