Java Reference
In-Depth Information
A mobile financial terminal would let you view graphs and charts using
JSR-226 SVG, perform secure and authenticated bank transactions using
JSR-177 SATSA and JSR-172 Web Services and store important reminders
using JSR-75 PIM.
We could find more examples and spend time going into detail for
each of them, but the point is clear - a world in which MSA is the Java
ME standard is a much more consistent and predictable world, which
allows the same application to run easily and more predictably on a
wider variety of MSA-compliant phones. After that, it is only natural that
a more predictable and consistent platform would enable more mobile
services to emerge and we are likely to see more and more advanced
Java applications that let us do more on our phone.
6.3 Spicing up Legacy MIDP Applications
If you have a successful Java application that runs on MIDP- or JTWI-
compliant platforms, it is quite likely that you need different versions of
the application that target different devices according to their capabilities
and the Java specifications which they support. This fragmentation can be
minimized by using MSA, so you spend less time on version management
and code maintenance.
This is similar to the transition from MIDP 1.0 (which did not have
gaming APIs and games had to use proprietary APIs from the manufacturer
or custom-made APIs) to MIDP 2.0 - existing games were upgraded to use
the new MIDP 2.0 gaming API. The consistency of the games increased
by using a standard API available across compatible Java platforms.
So what can you do with MSA, to help you as a developer and your
company? First, your application can become even better if you decide to
add capabilities to it and leverage MSA's strengths. You could include use
of additional Component JSRs that are not part of JTWI and enrich your
application with features such as SVG, location, and so on. To illustrate
how that can be done, let's take an example of a well-known existing
application, MobileAerith, and see how we can improve it using MSA.
MobileAerith is a demonstration photo management system (see
Figure 6.3). The user can take a picture with a phone camera, man-
age albums of photos, view thumbnails of the photos in the album, and,
when a thumbnail is chosen, view the bigger image. MobileAerith runs
on MIDP 2.0; it also requires JSR-135 MMAPI and uses JSR-226 SVG
extensively for the creation of a slick user interface that is a joy to behold!
Figure 6.4 shows the JSRs used by MobileAerith before it is enhanced
with MSA.
By now you probably want to go through the application code and run
it on your device. MobileAerith is part of the ME Application Developers
