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

8.2 MARKUP LANGUAGES FOR MOBILE DEVICES

So far, we have addressed the process of a mobile device fetching content from a J2EE server using a HTTP link. This model applies to many mobile service scenarios. As we discussed earlier, when we looked at WAP, the WAP protocols will also work with this model as they have been designed to work with HTTP very closely. As far as our J2EE environment is concerned, it will receive HTTP requests from WAP devices just like any other type of request. Hence, we do not need to resort to specific design approaches in these cases. We can still use JSP and servlet programs for our presentation logic.

What is unique to the mobile context is the nature of the information that the JSPs and servlets will produce. Clearly the information is targeted at devices that have various display characteristics, so we expect the need to adapt our designs to match each device accordingly. Ordinarily, web pages for the desktop world are very information-rich and can have very complex layouts. We have seen the complexity of browser display capabilities evolve from something akin to a word-processor document to something capable of supporting arcadegame levels of complexity in both display and interaction, all within the web browser. Contrast this with a legacy WAP device, like the Nokia 3410, with its monochrome display and resolution of 96 × 65 pixels. Figure 8.7 shows us what happens if we try to fit a standard web page into the screen of a 3410, which is an extreme ...