Full Description
This book does not tell a story. Instead, it is about stories. Or rather, in technical terms, it is about scenarios. Scenarios of system behavior. It con centrates on reactive systems, be they software or hardware, or combined computer-embedded systems, including distributed and real-time systems. We propose a different way to program such systems, centered on inter object scenario-based behavior. The book describes a language, two tech niques, and a supporting tool. The language is a rather broad extension of live sequence charts (LSCs), the original version of which was proposed in 1998 by W. Damm and the first-listed author of this book. The first of the two techniques, called play-in, is a convenient way to 'play in' scenario based behavior directly from the system's graphical user interface (QUI). The second technique, play-out, makes it possible to execute, or 'play out', the behavior on the QUI as if it were programmed in a conventional intra object state-based fashion. All this is implemented in full in our tool, the Play-Engine. The book can be viewed as offering improvements in some ofthe phases of known system development life cycles, e.g., requirements capture and anal ysis, prototyping, and testing. However, there is a more radical way to view the book, namely, as proposing an alternative way to program reactivity, which, being based on inter-object scenarios, is a lot closer to how people think about systems and their behavior.
Contents
I. Prelude.- 1. Introduction.- 2. Setting the Stage.- 3. An Example-Driven Overview.- 4. The Model: Object Systems.- II. Foundations.- 5. The Language: Live Sequence Charts (LSCs).- 6. The Tool: The Play-Engine.- III. Basic Behavior.- 7. Variables and Symbolic Messages.- 8. Assignments and Implemented Functions.- 9. Conditions.- 10. Branching and Subcharts.- IV. Advanced Behavior: Multiple Charts.- 11. Executing Multiple Charts.- 12. Testing with Existential Charts.- V. Advanced Behavior: Richer Constructs.- Loops.- Transition to Design.- Classes and Symbolic Instances.- Time and Real-Time Systems.- Forbidden Elements.- VI Enhancing the Play-Engine.- Smart Play-Out (with H. Kugler).- Inside and Outside the Play-Engine.- A Play-Engine Aware GUI Editor.- Future Research Directions.- VII Appendices.- A. Formal Semantics of LSCs.- A.1 System Model and Events.- A.2 LSC Specification.- A.3 Operational Semantics.- B. XML Description of a GUI Application.- C. The Play-Engine Interface.- C.1 Visual Basic Code.- D. The GUI Application Interface.- D.1 Visual Basic Code.- E. The Structure of a (Recorded) Run.- References.
