Question : Developing Instant Messenging in J2ME

Hi, I'm trying to develop an IM using J2ME.

So i need to build an IM server, IM MIDlet client install in my mobile.
The tools i'm using is JBuilder with Mobile set and Tomcat server.

So what else do i need ?
If i have a wireless card install in my notebook, is it poosible that my mobile are able to communicate with my notebook? How?

Is urgent.
Thanks a lot.

Answer : Developing Instant Messenging in J2ME

That's the key to the problem of Instant Messaging on mobile handsets.  Originally I wanted to implement an instant messaging system and discovered that there is no practical solution (as far as I am concerned).

The handset needs to poll the server at regular intervals to see if there is a new message.  Unless you're polling every couple of seconds, it's not going to look to "instant" :-(  However, if you do poll that frequently, you'll probably find that users get annoyed with how much data they transmit/receive and also, the requests will probably overlap due to network latency.

My chat application does a check (http request) every 30 seconds (or greater) depending upon what the user selects.  By default, the user needs to check manually.

This is all because there is no way to "push" information from the server to a mobile.  It looked like this was going to be solved by MIDP-2.0, but in reality, the only push technology that is going to be generally supported is via SMS.  This is because the network operators are not willing or able to provide an IP address for every mobile connected to the network.  To be honest, I don't expect this to happen until some time after IPv6 has been adopted as a general standard (probably 4 - 5 years at least).

When my app sends an http request, it includes the user ID and any message that is being sent with the request.  The server knows which "room" the user is in and can add the new message and return any outstanding messages that the user has not yet received.

The closest you will get to an Instant Messenger is to have an idea similar to my chat, but everyone will effectively be in a single room.  Instead of the room messages being sent between users, each message will need a destination user.