JAVA-BASED REAL-TIME PROGRAMMING

Chapter 1
Introduction
Goal: Understanding of book aims and scope.
Computers, such as microprocessors, are more and more often embedded
in products that the user does not perceive as computers. This is the case for
both consumer electronics (your CD player, mobile phone, etc.), home supplies
(your micro-wave oven, washing machine, etc.), vehicles (the engine control
in your car, airplane fly-by-wire control, etc.), building automation (elevator
control, temperature control, etc.), as well as for industrial equipment. We
want these things to be affordable, and we want to be able to trust their
operation, in particular when our life depends on them. Additionally, in some
cases, we want to be able to reconfigure, upgrade, or even program them,
possibly by downloading software components from a trusted supplier via the
Internet.
Most people think of a computer as the desktop type of computer (with
keyboard and display), but the number of embedded computers is bigger than
the number of all other types of computers, and the difference is increasing.
Moreover, the variety of types of processors and operating systems is much
larger in the embedded world, which includes the desktop types and many
others. Reasons for this variety include optimization to reduce the product
price and minimization of energy (from batteries) consumption.
Development of embedded software has for some years mainly been carried
out by hardware-aware programming using the C-language, and in some
cases even in assembly languages. This works well in simple cases when the
application demands and the hardware are known at design time, and the size
of the (statically defined) software is small. When applications increase in
size and must be rapidly developed (time to market), and perhaps need to
be on-line upgradeable, more programming support is needed. In particular,
for critical applications (safety critical as in an airplane, mission critical as in
space/military/nuclear tasks, economically critical if the survival of the com-
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