Notification.getSource() what should it return?

[azakkerman]

Hi, guys,

I am reading up on Juha's book while trying to build something on top of JMX. On page 61 (Chapter 3) it says that getSource() returns an object which is an ObjectName reference to the MBean that broadcast the notification.

I thought that it means that it basically returns an ObjectName (or something castable to it). Well, it does not! It seems to be returning a reference to the MBean, i.e. a pure java reference to the underlying object that implements the MBean. As soon as Notifications get delivered remotely, this becomes worthless. Did I misunderstand the book? Is this a bug?

(I am using JBoss 3.0.0RC1 with whatever version of JBossMX it is using but it seems that the latest snapshot in CVS still does the same). I was not able to find anything in the specification or elsewhere to resolve this.

Sincerely,

Anatoly Akkerman.

[juha]

yes its a "known issue" ( a feature ? :) ) of the 1.0 implementation.... should be fixed in the current head IIRC.

-- Juha

[azakkerman]

> yes its a "known issue" ( a feature ? :) ) of the 1.0
> implementation.... should be fixed in the current
> head IIRC.
>
> -- Juha


Well, as I said before, the Notification class from the HEAD seems to just return the source of the Event (albeit a copy of it), not the ObjectName. So it appears not to be fixed.

[juha]

did you try it, or are you just looking at the source?

The notification class *should* return the source of the event, its the servers responsibility to map that reference to object name.

-- Juha

[azakkerman]

> did you try it, or are you just looking at the
> source?
>
> The notification class *should* return the source of
> the event, its the servers responsibility to map that
> reference to object name.
>
> -- Juha

I just looked at the source. I am confused at how to use it then. Can I just typecast the result of getSource() to ObjectName?

[adrian.brock]

Yes,

If you register your listener with the MBeanServer.

Regards,
Adrian