The game engine has a lot of structure, but it is basically implemented in a game main loop. The primary loop in the program contains the most important structure of the program framework. J2ME procedures generally contain two class files, one is a MIDlet, one is displayable. Generally, I put the main code of the game in the Displayable this class. This class is an event-driven program with three major corresponding functions void Paint (GRAPHICS G), Void KeyPressed (int keycode).
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J2ME mobile game engine program structure