Occi AQ callback not called

Question

I have written code for dequeing messages with blocking calls (Consumer::recieve), which works fine. Now I try to register a callback function, which should be called when a message is in the queue.
Some code:
void aq_connection::create_callback() {
payload = new Bytes(env); //?
Subscription newSubscription(env);
newSubscription.setSubscriptionNamespace(oracle::occi::aq::Subscription::NS_AQ);
newSubscription.setProtocol(oracle::occi::aq::Subscription::PROTO_CBK);
newSubscription.setPayload(*payload);
newSubscription.setCallbackContext((void *)this);
newSubscription.setSubscriptionName(quename + ":" + config->subscribername);
newSubscription.setPresentation(oracle::occi::aq::Subscription::PRES_DEFAULT);
newSubscription.setNotifyCallback(&aq_connection::event_message);
mye callback method is defined like this:
static unsigned int event_message(oracle::occi::aq::Subscription &sub ,oracle::occi::aq::NotifyResult *not) {
std::cout << "got message\n";
return 0;
The problem is, the event_message function is never called... I send in messages into the queue with this stored procedure:
message := OURMSG_TYP(p_id, p_msg_type_id, p_msg, p_operation, p_data);
enqueue_options.visibility := DBMS_AQ.ON_COMMIT;
     enqueue_options.relative_msgid := NULL;
     enqueue_options.sequence_deviation := NULL;
     enqueue_options.transformation := NULL;
     message_properties.priority := 1;
     message_properties.delay :=     DBMS_AQ.NO_DELAY;
     message_properties.expiration := p_expiration;
     message_properties.correlation := NULL;
     --message_properties.recipient_list :=
     message_properties.exception_queue := vcp_exception_queue_name;
     --message_properties.sender_id :=
     message_properties.original_msgid := NULL;
     message_properties.transaction_group := NULL;
     message_properties.user_property :=     NULL;
     DBMS_AQ.ENQUEUE(
     queue_name => our_queue_name,
enqueue_options => enqueue_options,
message_properties => message_properties,
payload => message,
msgid => message_handle
Any obvious reason why my callback is never called?
regards,
Sverre

Answer 1

Thanks, once again. Sorry for my naive questions, but I'm unable to find a good example for this...
After registering the Subscriber, and creating the environment in EVENT mode, it seems like it is picking up the message. Once I send a AQ message, I get an error from visual studio, telling me the variable ESP was not properly saved across a function call. At least it reacts now :)
Could it be that I'm doing something wrong when defining or hooking my callback function? The breakpoint in the callback function is never called....
my registering routine now looks like this:
void aq_connection::create_callback() {
payload = new Bytes(env); //is this the correct way?
Subscription sub(env);
sub.setSubscriptionNamespace(oracle::occi::aq::Subscription::NS_AQ);
sub.setProtocol(oracle::occi::aq::Subscription::PROTO_CBK);
sub.setPayload(*payload);
sub.setCallbackContext((void *)this);
sub.setSubscriptionName(quename + ":" + config->subscribername);
sub.setPresentation(oracle::occi::aq::Subscription::PRES_DEFAULT);
sub.setNotifyCallback(&aq_connection::event_message);
subs.push_back(sub);
conn->registerSubscriptions(subs);
I thought it was ok to create a local Subscription instance, as I put it into the global subs-vector.
Thanks in advance,
Sverre