Running J2ME Applications on Palm-powered Devices

he Palm Treo platform has gained wide appeal as a communications device for mobile professionals, enjoying several launches in the enterprise over the last few months. With the wide use of Java in business and the capabilities of these devices (including a large screen and keyboard), it only makes sense to explore using the Palm Treo (or related devices including the LifeDrive) to run legacy and new Java MIDP applications. Fortunately, the IBM WebSphere Everyplace Micro Environment for Palm OS Garnet (WEME) provides a MIDP2.0/CLDC 1.1 compliant run-time with support for file and personal information manager (PIM) integration (via JSR-75) as well as Web services development with JSR-172. This article shows you how to migrate your J2ME applications to Palm OS using the WEME, assuming you have some previous experience with Java MIDP development. If you need an introduction to J2ME, see one of the many other articles on J2ME from DevX (a full list can be found here).

Setting Out with the Developer Tools
In order to run J2ME applications, a target device must have a Java runtime consisting of the Java Virtual Machine (JVM) and the libraries that implement the J2ME classes. Java on Palm-powered handhelds is not new: Sun itself released a runtime for Java in the late nineties, which later became the basis for the first J2ME runtime. However, until recently it was difficult to obtain a Java runtime for Palm-powered devices appropriate for end-user application execution—most were fraught with stability, performance, and licensing issues. The IBM WEME changed this, providing a state-of-the-art stable runtime for many Palm-powered devices, including the Treo, LifeDrive, and select Tungsten and Zire devices.