Re: [xmlblaster] null oid in unsubscribe

[Michele Laghi <laghi at swissinfo.org>]

Hi Jason,
The 'oid is null' message tells you no topic was hit by your XPATH 
query. This is probably the case since your message was erased (either 
explicitly or by a timeout).

If you want to unsubscribe even when the topic is not here anymore, you 
could keep the SubscribeReturnQos when subscribing (lets call it 
subRet). Then when unsubscribing invoke:

UnSubscribeKey uk = new UnSubscribeKey(glob, subRet.getSubscriptionId());
 UnSubscribeQos uq = new UnSubscribeQos(glob);
 UnSubscribeReturnQos[] urq = con.unSubscribe(uk, uq);

I think this is a better approach since you specify exactly which 
subscription you want to remove.

Saluti
Michele



Jason Martin wrote:
> Another question; how does one unsubscribe from a dead topic.
> Scenario:
>
> 1. Subscribe to oid
> 2. Message gets published and consumed.
> 3. Time passes.
> 4. Attempt to unsubscribe via xpath, get 'oid is null' error.
> 5. New message published and consumed.
> 6. Immediately unsubscrube, get ok result.
>
> Am I missing something about how unsubscribes work?
>
> -Jason Martin


--
Michele Laghi
mailto:laghi at swissinfo.org
tel. +46 8 7492952 / mob. +46 70 4103964
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