While it's completely possible to develop J2ME apps using an actual device installed with the CLDC and MIDP components, many developers will opt for a graphical environment that makes use of emulators for testing one app on multiple devices. If you've had any experience at all developing for mobile devices, you'll know not to rely too heavily on these emulators for production code, but they're handy for quick testing and prototyping. Sun has provided the J2ME Wireless Toolkit for use in stand-alone mode or as a plug-in to their Forte Java development environment. The toolkit requires JDK 1.3 or higher and is currently available for Windows environments only. The toolkit comes with two sample apps (UIDemo and "example") along with four emulators: DefaultGrayPhone, DefaultColorPhone (see Figure 1), MinimumPhone, and Pager (see Figure 2).
The DefaultColorPhone emulator.
The Pager emulator.
The purpose of this toolkit is to provide a graphical environment for creating, managing, and testing J2ME projects against multiple emulators. It does this successfully and is a good "starter" environment for anyone wanting to begin building applications using J2ME.