Next Generation Wireless Applications: Creating Mobile Applications in a Web 2.0 and Mobile 2.0 World, 2nd Edition

11.6 JAVA PLATFORM APPLICATIONS

So far, we have looked at embedded applications and browser-based applications. We are now going to explore the remaining option, the Java platform, which in some sense might be the best of both worlds, especially in its newest variants called Java 2 Micro Edition (J2ME), which is going to be the focus of our attention. We shall now examine the use of Java for mobile devices, highlighting the key attributes of this approach whilst comparing with the alternatives.

To understand the use of Java for mobile devices, we need to first summarise what is meant by Java. What is this technology is all about? We have already looked in some detail at Java 2 Enterprise Edition (J2EE); but, we did so from a systems perspective, focusing on its ability to support highly scaleable applications based on the CS architecture. We did not examine the Java programming environment itself, only its features within the J2EE environment, like RMI and JMS. It seems obvious that J2EE is not a suitable technology for implementing applications that run on mobile devices. We don't need clustering, distributed processing and heavy-duty database access on a mobile device!

Before exploring the general concepts behind Java, we might sensibly question why bother at all with running Java on mobile devices. Certainly, most of the heavy-duty features in J2EE are not required, so why not use a different technology altogether; indeed, what does it mean to support Java on a small device? ...