Packaging Java in Applications for Embedded Systems
Running Big Things On Small Devices

Aldo Eisma,
Object Technology International, Inc., The Netherlands
aldo_eisma@oti.com

Traditionally, most embedded systems used to be programmed in languages like
C and assembler because they were simple and static and had relatively long
life cycles. With the advent of pervasive computing, bringing us all sorts of
new dynamic, networked and complex embedded devices, there is a strong
interest for programming these devices in the Java programming language. The
limitations and special characteristics of embedded devices require a new
approach for the Java VM, class libraries and supporting development
tools. One of the main components in the embedded Java development
environment is the packager. The packager collects Java class files and
resources and builds a run-time image that can be stored in ROM, minimizing
startup time and decreasing RAM requirements on the device. The images
contain pre-linked optimized Java class files from which redundant and unused
elements have been removed. Various techniques have been researched by IBM
Watson and OTI, and have been implemented in IBM's VisualAge Micro Edition
SmartLinker and VM components. An introduction to the issues and an overview
of the techniques used is given in this presentation.