Java Platform, Micro Edition
The Java™ platform is available in three different editions, which serve the various capabilities of different types of devices:
All editions are similar in their fundamental level and follow the general Java characteristics, such as automatic garbage collection and platform independence via virtual machine utilization. Java Micro Edition aims to offer a standard framework for developing Java applications for embedded devices, such as mobile phones, and is adapted to an environment with limited memory and other resources. Java ME shares some packages with Java SE and Java EE, which means you can easily adapt your Java language skills to creating mobile applications.
The Java ME platform has two defined subsets of libraries, called configurations: Connected Device Configuration (CDC) and the more restricted Connected Limited Device Configuration (CLDC).
On top of these configurations are profiles, which concentrate even further on a specific group of devices. Mobile devices use the Mobile Information Device Profile (MIDP) on top of CLDC, which adds class libraries specific to devices such as cell phones and PDAs. Any embedded system with a CLDC configuration and MIDP profile can run applications written for any other platform with corresponding libraries.
The following figure presents an overview of Java platforms.
Figure: Java platform editions
Why use Java ME?
Java ME is an industry-wide technology, with most major manufacturers offering a range of devices with Java ME support. This means that, in addition to the huge market offered by the 1 billion Nokia devices in use today, your application has the opportunity to reach almost all of the nearly 3 billion mobile devices in use around the world.
Java applications offer the potential to reach this market because of high levels of consumer acceptance. Consumer acceptance has been driven by the availability of a robust download and installation mechanism included with Java ME, which in turn has prompted operator support for Java application downloads. These built-in mechanisms also mean that your intellectual property is protected.
Whether you are developing games, personal productivity, news and information, enterprise, or entertainment applications, Java technology and Nokia's platforms offer the APIs you need to take full advantage of mobility.
If you are not already using the Java language, learning it is easy, with many resources available, including Java ME-specific training and documentation available from Forum Nokia.