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A mathematical and logical foundation for the specification and development of interactive systems based on a model that describes systems in terms of their input/output behavior. Based on this model, the authors build a basic method, called FOCUS, that enables interactive systems to be described by characterizing their histories of message interaction. The book progresses from an introduction and guided tour of FOCUS through streams, specifications and their properties, and behavioral, interface, and conditional refinements.

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1.Introduction; 2. A Guided Tour; 3. Basics; 4. Streams; 5. Specifications; 6. Examples; 7. Properties of Specifications; 8. Equational Specifications of State Transitions; 9. Access Control System; 10. Tables and Diagrams; 11. Abracadabra Protocol; 12. A/G Specifications; 13. Memory with Locking; 14. Refinement; 15. Behavioral Refinement; 16. Interface Refinement; 17. Conditional Refinement; 18. Final Remarks; A. Operators for Stream Tuples; B. Glossary of Terms; C. Bibliography; D. Glossary; E. Index

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