JAVA-BASED REAL-TIME PROGRAMMING

Preface
This work, which should result in a freely available book, documents how
to carry out safe 1 , flexible 2 , portable 3 and free 4 programming of embedded
systems, such that the software without modifications can run on both small
embedded devices as well as on standard Java platforms (JDK1.4.1 or later).
The approach is motivated by and based on the following insights:
• Efficient development of future software will increasingly be made for
embedded systems with network connections and combined real-time
and desktop-like functions. That requires the safe, flexible, and portable
software techniques.
• The idea of “write once run anywhere” that was formulated for Internetready
software is highly desirable for embedded software. That is, embedded
software must exist in portable form that supports deployment
into specific configurations according to application needs.
• It is most suitable to use an object-oriented and industrially accepted
language that fulfills the requirements on safety and flexibility. Java
is the most available and portable such language, with possibilities for
automatic translation to the Microsoft .NET platform if needed.
• The standard Java platform does not support real-time execution, but it
supports concurrency and real-time properties are open to each implementation.
By providing run-time solutions for real time, together with
compilation to traditional binary code, Java-based real-time would be
very attractable.
1 Software components stay in their so called sandboxes; execution cannot harm unrelated
data or code. Here this is accomplished by using the Java language and it's built-in safety.
2 Execution adopts to the properties of the underlaying runtime system; concurrency
correctness is maintained while real-time performance varies from hard to soft in a flexible
manner according to the properties of the OS, managed by supporting classes.
3 Developed applications run without recompilation on any type of computer to which the
Java platform has been ported, and with recompilation on any type of embedded processor.
A C compiler and a set of native functions is then needed for such embedded processors.
4 Software development, compilation, deployment, and execution should be possible without
any costs (royalties, fees for libraries, etc.) or delays (purchasing, legal matters, etc.)
for licenses (documents, dongles, etc.); for student use and for agile product development.
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