How to handle unsupported events

parminder.grewal

I am new to using the Java based RFA / OMM api (we currently rely on the jsfc apis)

Looking through the examples on how to handle ItemSubscriptions, I found an interesting piece of code

if (event.getType() != Event.OMM_ITEM_EVENT)

{

System.out.println("ERROR: " + _className + " Received an unsupported Event type.");
consumerComponent.cleanup();

return;

}

if I understand this correctly , if an unsupported event type is received, we just shut down the consumer which could affect real time streaming of data. Is this the recommended handling of this kind of event or could we just ignore the event and go on processing next event

My concern is that we shut down consumers altogether, which is unacceptable. We could try restarting them, but if we continuously get the same condition, we could end up in a loop of starting and shutting consumers.

Has anyone encountered this issue before ? Any suggestions are welcome

Nipat Kunvutipongsak

Hello @parminder.grewal,

In RFA Java (as of version 8.0.1.X), there are various event types as follows:

Event Types	(Constant Value)
---------------------------------
AUTHORIZATION_EVENT	(401)
COMPLETION_EVENT	(2)
CONNECTION_EVENT	(113)
OMM_ACTIVE_CLIENT_SESSION_PUB_EVENT	(125)
OMM_CMD_ERROR_EVENT	(122)
OMM_CONNECTION_EVENT	(129)
OMM_CONNECTION_STATS_EVENT	(130)
OMM_INACTIVE_CLIENT_SESSION_PUB_EVENT	(126)
OMM_ITEM_EVENT	(121)
OMM_LISTENER_EVENT	(124)
OMM_SOLICITED_ITEM_EVENT	(123)
PUB_ERROR_EVENT	(106)
TIMER_EVENT	(3)
UNDEFINED_EVENT	(0)

For an OMMConsumer type of application, you can receive a designate Event Type from registering a corresponding Interest Specifications (IntSpec).

OMMConsumer.registerClient(EventQueue
aQueue, InterestSpec anInterest, Client aClient, java.lang.Object aClosure);

There are four types of IntSpecs that you can put as the argument of OMMConsumer Event Source as follows:

OMMItemIntSpec -> OMMItemEvent

OMMErrorIntSpec -> OMMCmdErrorEvent

OMMConnectionIntSpec -> OMMConnectionEvent

OMMConnectionStatsIntSpec -> OMMConnectionStatsEvent

Furthermore, a COMPLETION_EVENT is a special event of common package. You can switch to receive or not receive this event from this method

Session.createEventSource(int
eventSourceType, java.lang.String name, boolean wCompEvents);

In summary, it is possible that the application can receive more Event Types other than just OMM_ITEM_EVENT.

So, you may need to check how many interest specification(s) that the application has registered (including the COMPLETION_EVENT case). Then, you need to adjust and relax your current logic that checks the Event Types to correspond with the registered interest specification(s).

Alternatively, you may try to debug the incoming event that goes through your logic, check its code (as mentioned above) to identify the Event Type. If you consider it as the unwanted event, you have to review your source code where the application registers surplus interest specification(s). If so, just remove it, restart the application again. The unwanted event(s) should no longer appear anymore.

Hope this helps!