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Advice on building J2ME apps

 
Ricardo Marques
Greenhorn
Posts: 27
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Last year I put myself to develop a small application in this platform. The information I had on the topic was quite sparse. However, this didn't detract me from my real objective.
The application was developped for the Palm III, and worked together with a Conduit and JDBC access to a Oracle DB. The app should store some data on the Palm, when it was not connected to the DB. Enough about that, let me delve into what is really important.
Building the app isn't very difficult. Once you've fine targeted the type of devices in which your application is to be run, you're halfway through.
You can also develop your application considering it is to be run on several devices, which might make your life a little harder, but not that much.
Consider the (small) amount of memory available, the (small) size of the screen and it is almost done.
You might think the screen is awfully to small. Well, I thought so too at first. However, it is just a matter of scaling and reducing the information to what is really needed.
The memory constraint is a bit more heavy. You'll have to keep in mind that your application will have to share the emory of the device with other apps. So, follow the KISS approach: Keep It Supremely Simple.
I would advice you to read a couple of articles on the net about building conduits, if you come to need them. I did not buy any books at the time, since conduit development was (at least IMHO) at its very first stages.
As for the application itself, it will be Java, with a few constraints... At the time, I did not use AWT or anything similar, I coded the interface entirely based on the primitives for the graphical objects. Today, I would use AWT for sure. Or Swing, which I personally don't know if it works in J2ME...
You will need Event Listeners, but what I found was that these are really similar to the ones used for Applets... A simple search in GOOGLE for "sample J2ME applications source code" (without the quotation marks) will give you a nice bunch of links where you can start.
About the mobile device, and in this case it is the Palm III, the storing of data was accomplished as a text file. Hence, every field in every record was immediately after the previous, with no separation between them, everything being stored as a continuous string.
Hope this helps people starting at J2ME
 
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