Re: [Embedlets-dev] Re: JAPL part of specification

[Brill P. <bri...@ro...>]

> I thought that JAPL was going to be a separate specification, since it
> would/might have applicability outside of an Embedlet container?

So did I; I still do ;)

> > So... what I need to understand is how Outpost would be setting and
getting
> > attributes of a peripheral?
>
> An Embedlet would have a reference to the JAPL device and would use
whatever
> API the JAPL device exposed to set/get any attributes the device had
exposed.

Thats exactly what I though should happen, but when I went to take a look at
the Embedlet to extend it, there didn't seem to be any way for IO to happen.

[...]

> > What I don't understand is how the embeled talks to the JAPL device.
> > What is looked like, extending Embedlet is that the embedlet receives
events
> > from the system... now I assumed that I would do something different
depending
> > on the event code.
>
> Assuming that the JAPL stuff is intended to be independent of the Embedlet
> container (something we talked about a long time ago), here is the way I
> think you should consider linking the two:
>
> 1) Create your JAPL drivers with an exposed API.  The JAPL device should
NOT
> have a reference to any Embedlets, nor be dependent on ANYTHING in the
> embedlet spec (eg. no imports of org.embedlet or org.outpost packages).

Ok, good so far... done.

[...]

> 1) JAPL device gets an interrupt.
> 2) JAPL device does a callback into the JAPL "Proxy" Wrapper.
> 3) The wrapper takes the interrupt data, puts in in an Embedlet Event and
> sends it (note: it does not know who the consumers are going to be).
> 4) An Embedlet (registered as a consumer for that particular event type)
> receives the event and then does something with it (possibly issuing JAPL
API
> calls against the originating device, setting/getting attributes).

[...]

Ok, so the IO does happen with events... How does the external caller
request data from JAPL device? I assume that in that case the external
"listener" would just have a proxy "event generator" that sent events out
into the system... and the "JAPL control embedlet" would be registered as a
listener?

> Make sense?  Do I need to write an example to show you how this is
intended
> to be implemented?

Well, I'll eventually figure it out anyway (key factor is my time is taken
with money making at the moment) ;) but I don't think a very simple example
could go wrong especially as outside parties begin to take interest. Anyway,
I've been using our Outhouse impl for the moment.

- Brill Pappin