Text Box: Glossary of Terms J2ME – Java 2 Micro Edition, a version of Java for smaller devices, including mobile phones, automotive navigation system, networks switches, PDAs, digital TV's, smartcards, etc. Basically, anything without enough capability (memory, etc.) to run J2SE. J2ME covers a much larger array of devices with widely differing capabilities, so more specification in the form of a configuration and profile is needed in order to develop an application. Although most of the basic classes and syntax are exactly the same as J2SE many packages are not available. Some of these include graphics packages (swing & awt), java beans, javax.sound libraries, BufferedStreamReaders/Writers, FileStream classes, or Java Native Interface. CLDC – Connected Limited Device Configuration, a specification for small devices, such as cell phones, pagers, and low-end PDA's. Defines some base classes and memory requirements. MIDP, as well as some other profiles are built on top of CLDC. KVM – Kilobyte Virtual Machine, a Sun reference implementation of a virtual machine implementing the CLDC specification. It uses a very small footprint, and can be executed with only kilobytes of memory allocated, rather than megabytes. MIDP – Mobile Information Device Profile, the profile of Java implemented by most mobile phones. This profile contains two GUI API's in the java.microedition.lcdui package, a high level UI which make lists, choice boxes, etc. quite easily, and a lower level UI which allows drawing of pixels, images and characters directly to the screen. They are different from both awt and swing, but significantly simpler. User interaction is event based, and with higher level UI, event handling is already handled for you. Minimum requirements for MIDP hardware include: Screen-size: 96X54 pixels, 1-bit depth (black & white), approximately square pixel shape. Memory: 128KB non-volatile memory for midp components, 8 KB for application created data, & 32KB for runtime (the Java Heap). Networking: two-way wireless, possibly intermittent, with limited bandwidth. These requirements are pretty spare, although the devices we'll be using are significantly better. However these are what you need to plan for if you want your app to be compatible forany MIDP device. Most devices currently on the market use MIDP 1.0. MIDP 2.0 includes some nice additional packages for developing games, including transparent images, graphical layers and tiling, and sound. MIDlet - An instance of this class is what every MIDP application starts from. It has several required methods, like startApp() and destroy App(), which are called when a program is executed or quit. Often synonymous with a MIDP application. PNG – Portable Network Graphics, a public domain equivalent of the GIF format. This is most likely the format you'll need to put graphics, since its the only one required to be implemented by MIDP. Wireless Toolkit - A free development environment that can be used to compile, emulate and sign MIDlets. Can be used in conjunction with an IDE, or just a text editor. <<Back