I suppose this is where the
Thread class and Runnable interface come in handy, to do two things at once. You'll have to
test the performance on that for grabing data running in real-time though. Also, read about thread safety (synchronize, volatile ).
And, the storage options:
javax.microedition.rms
or
FileConnection API (jsr 75) -- an optional package.
If you have this, you can test for your midlet's private directory (accessed only by it, so you'll also need to access the data through your program to use it later) by requesting the System property:
fileconn.dir.private.name.
You have to be careful though. I could easily see a real time storage box be filled up by a continus feed.