Specification and Runtime Checking of Timing
		 Constraints in Safety Critical Java
				  by
			    Ghaith Haddad

			       Abstract

The Java platform is becoming a vital tool for developing real-time
and safety-critical systems. Design patterns and the availability of
Java libraries, both provide solutions to many known
problems. Furthermore, the object-oriented nature of Java simplifies
modular development of real-time systems. However, limitations of Java
as a programming language for real-time systems are a notable obstacle
to producing safe real-time systems. These limitations are found in
the unpredictable execution model of the language, due to Java's
garbage collector, and the lack of support for non-functional
specification and verification tools. In this dissertation I introduce
SafeJML, a specification language for support of functional and
non-functional specifications, based on an implementation of a
safety-critical Java platform and the Java Modeling Language
(JML). This dissertation concentrates on techniques that enable
specification and dynamic checking of timing constraints for some
important Java features, including methods and subtyping. SafeJML and
these dynamic checking techniques allow modular specification and
checking of safety-critical systems, including those that use
object-orientation and design patterns. Such coding techniques could
have maintenance benefits for real-time and safety-critical software.

Keywords: Safety-Critical Java (SCJ), SCJML, real-time programming,
safety-critical software

2000 CR Categories:
D.2.0 [Software Engineering]
        General --- languages, tools, SCJML.