Transactions in CORBA Client Applications

CORBA::Object_var var_transaction_current_oref =  
     Bootstrap.resolve_initial_references("TransactionCurrent");
CosTransactions::Current_var transaction_current_oref=
     CosTransactions::Current::_narrow(
              var_transaction_current_oref.in());

Java Example

org.omg.CORBA.Object transCurObj =
     gBootstrapObjRef.resolve_initial_references(
                              "TransactionCurrent");
org.omg.CosTransactions.Current gTransCur=   
     org.omg.CosTransactions.CurrentHelper.narrow(transCurObj);

Visual Basic Example

Set objTransactionCurrent =
             objBootstrap.CreateObject("Tobj.TransactionCurrent")

Step 2: Use the TransactionCurrent Methods

C++ Example

//Begin the transaction
transaction_current_oref->begin();
try {
//Perform the operation inside the transaction
     pointer_Registar_ref->register_for_courses(student_id, course_number_list);
     ...
//If operation executes with no errors, commit the transaction:
     CORBA::Boolean report_heuristics = CORBA_TRUE;
     transaction_current_ref->commit(report_heuristics);
}
catch (CORBA::Exception &) {
//If the operation has problems executing, rollback the 
//transaction. Then throw the original exception again.
//If the rollback fails,ignore the exception and throw the
//original exception again.        
try {
     transaction_current_ref->rollback();
}
catch (CORBA::Exception &) {
            TP::userlog("rollback failed");
}
throw;
}

Java Example

try{
   gTransCur.begin();
   //Perform the operation inside the transaction
   not_registered = 
       gRegistrarObjRef.register_for_courses(student_id,selected_course_numbers);


   if (not_registered != null)

     //If operation executes with no errors, commit the transaction
     boolean report_heuristics = true;
     gTransCur.commit(report_heuristics);

   } else gTransCur.rollback();


} catch(org.omg.CosTransactions.NoTransaction nte) {
    System.err.println("NoTransaction: " + nte);
    System.exit(1);
} catch(org.omg.CosTransactions.SubtransactionsUnavailable e) {
    System.err.println("Subtransactions Unavailable: " + e);
    System.exit(1);
} catch(org.omg.CosTransactions.HeuristicHazard e) {
    System.err.println("HeuristicHazard: " + e);
    System.exit(1);
} catch(org.omg.CosTransactions.HeuristicMixed e) {
    System.err.println("HeuristicMixed: " + e);
    System.exit(1);
}

Visual Basic Example

' Begin the transaction
'
objTransactionCurrent.begin
'
' Try to register for courses
'
NotRegisteredList = objRegistrar.register_for_courses(mStudentID,
     CourseList, exception)
'
If exception.EX_majorCode = NO_EXCEPTION then
     ' Request succeeded, commit the transaction
     '
     Dim report_heuristics As Boolean
     report_heuristics = True
     objTransactionCurrent.commit report_heuristics
Else
     ' Request failed, Roll back the transaction
     '
     objTransactionCurrent.rollback
          MsgBox "Transaction Rolled Back"
End If