Highlights

MIDP applications have to run seamlessly on many devices. You've already seen how this can be a challenge in the user-interface arena. The trick there was to use abstract concepts that would be mapped to the screen by a device-specific implementation.

MIDP's approach to persistent storage is basically the same. Your application could run on a device with flash ROM, battery-backed RAM, or even a small hard disk. MIDP applications don't really care; all they know about are small databases called record stores. It's up to the device's MIDP implementation to map record stores in some reasonable manner to whatever persistent storage is available.

These are small amounts of data we're talking about; the MIDP specification dictates that the minimum amount of persistent storage is only 8KB.