how IM client being implemented

[nicklv]

Hi,

Would just like to get some opinion on this.

My understanding is that MIDP1.0 requires only http to be implemented. And with http, there is no way for a server to initiate a connection to a client. With this restriction, am curious to find out how some of the other developers manage to implement an instant messaging client.

To expand further, there is no IP address associated with a mobile handset. How can a server contact a client.

[shmoove]

Polling is the only viable answer. The client requests updates (with an http request, of course) from the server every x seconds.
Some phones support sockets, but polling is the only truly portable way to achieve this for now.

shmoove

[bvolk]

We use a 'Gateway' server to talk to the various IM flavors ... and have the J2ME client continually poll that server for new chat messages and buddy-list status updates.

[doctordwarf]

Guys, I've got an idea about this IM for J2ME.

When you open HTTP connections, you can send and receive data at any time, right?

Why wouldn't you send just something like one symbol per minute, not to timeout the connection and send real messages when IM message arrives?

[bvolk]

That's pretty much what we do ...

[d_ced]

hi bvolk,

In your solution do ou keep HTTP COnnection open or each poll requires a new HTTP (A new TCP) connection ?

[bvolk]

I don't know ... I'm management ;-)

We do use a seperate thread ... and we keep that thread alive.

[rsmithh]

Holding an http connection open doesn't work on Series 40, only on Series 60. We have an IM client for MSN (and Yahoo) and most of the problems we faced were on Series 40 and the intervention of the operator's WAP gateway. Still, it *can* be done, just takes lots of coffee and piza :-)

[bvolk]

Yes, I think holding the HTTP connection doesn't work.

How did you get around the WAP-Gateway problem? Other than changing to a alternative gateway.

[d_ced]

Rsmith, Bvolk

Question: Having or not a WAP gateway is clearly carier dependant. In other words, it's up to my mobile carier to decide or not to give direct access on the Internet ?

regards.

[d_ced]

Rsmith,

Do you have any demos or a web site where i can try your application ?

regards
Ced

[barryIyer]

Can any one explain me . Is Http the only possible solution for all handsets to implement IM?
Or any plain socket connections can serve this ?

If only Http then how the request messages are sent to web server. And how does a webserver respond to request.

[bvolk]

The current phones only support HTTP networking from J2ME. So we use a gateway server that responds to these HTTP requests and makes the appropiate socket connections to the various IM services.

[doctordwarf]

rsmithh
Holding an http connection open doesn't work on Series 40, only on Series 60.

Could you explain why it doesn't work.
Is it timouted fast? Or maybe phone doesn't actually send anything until the conection is closed?

I'm confused

[lightyear]

hello all,

one year later after this last post in this thread
any new ideas about this issue?

we are developing a turn-based game in midp 1.0/http and dont want to poll any longer

perheps we can restart discussion about this
any fresh ideas about that?
thanks