When you?re writing a Java application for the server or desktop, you can be reasonably sure that the Java platform will fulfill its ?Write Once, Run Anywhere? promise. But when you?re dealing with code that will run under the J2ME Mobile Information Device Profile (MIDP), things get a little trickier. If you?ve downloaded the Web Services Tool Kit for Mobile Devices (WSTKMD) and are eager to write mobile Java Web services, you?ll need to check out the warnings in this article(see Resources).
The MIDP programming environment offers a very limited amount of functionality to the programmer. In addition, MIDP has been implemented differently on different devices. Therefore, you cannot program to MIDP and assume that your application will look and behave consistently in varying environments. For example, the MIDP GUI library does not support a single class for buttons. You can draw buttons natively, or you can rely on each individual MIDP implementation for each device to provide buttons for your menu items.
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