The Java language provides many benefits to application developers, including memory access safety, platform portability, and very high levels of productivity. However, some of the very Java language features that bring these benefits, such as the garbage collector, have also made it difficult or impossible to create applications with bounded response time characteristics. Implementations of the real-time specification for Java (RTSJ) are now available that have proven to be capable of supporting all aspects of real-time systems. This paper discusses the principal concepts underlying the RTSJ, use of the RTSJ's features in real-time applications, the most critical considerations that must be addressed by RTSJ-compliant Java virtual machine implementers, and two example RTSJ-compliant application designs that can fully utilize the RTSJ to portably support their performance requirements.

Summary form only given, as follows. Static models are not appropriate for next-generation distributed real-time applications that are likely to be adaptive in nature, (for example, to provide a high degree of fault tolerance). During the last few years, the real-time systems community has started to counter this criticism by extending traditional work to cover newer application domains, The central problem remains, however, that the concept of adaptivity is often domain-specific and sometimes ill-defined in the context of bringing distributed real-time systems concept into better focus. Accordingly, be it resolved that future distributed embedded and real-time applications will be adaptive and that meanings, challenges and research paradigms await discovery. The charge to the panel is to defend (or to dismiss as fluff) the above resolution.

In an effort to promote the use of Ada in embedded system development, a realistic avionics application model whose hard real-time properties are fully predictable has been generated. This was done starting with a rate monotonic analysis of a set of typical fully synchronized periodic and aperiodic avionics tasks drawn from an idealized attack aircraft mission computer. The authors describe this avionics case study and its goals, examine the resulting design issues and trade-offs, and investigate the ability of the rate monotonic analysis model to predict its performance under a heavy load.>