Introduction

• Known in its longer form as Java Platform Micro Edition, J2ME is not only used on iDEN phones, but also as the embedded firmware that manages simple electronic devices from industrial controls and set top cable boxes. The J2ME environment uses an optimized version of Java's runtime environment. In addition to games development, J2ME can extend the functionality of onboard software applications, be used as a security protocol and interact with iDEN phone peripheral devices such as memory cards.
  
  

GameCanvas

• Included with J2ME is a user interface engine known as GameCanvas. GameCanvas provides tools that allow developers to set up the game's screen. Using the Graphics feature of GameCanvas enables developers to draw shapes and figures, as well as insert images that are used in the game. Another feature of GameCanvas is its ability to buffer the game off-screen, which minimizes the amount of the time user may have to wait for items in the game to load.
  
  

Sprites

• Sprites are used across all game development platforms. They serve as the avatars or characters in the game and are also used to represent other visual components of the game. They can be complex images or simple visual representations. The J2ME platform renders the sprite as a continuous action and draws several frames of animation from one image file. In order for sprites to work, the frames in the image file need to share the same width and height.
  
  

GameManager

• GameManager is another critical J2ME feature used in developing games on the platform. It serves as a manager for the series of layers that make up the visual appearance of the game. GameManager automatically renders each visual layer in an order specified by the software developer. Using this feature, developers can add and remove layered images, as well as define conditional layers so the visual appearance changes as the user plays the game.