tailieunhanh - Lecture Building reliable component-based systems - Chapter 6: Semantic integrity in component based development

This chapter presents the following content: Introduction, general issues of semantic concern, levels of formalism for semantic specifications, phases in a component’s life, a taxonomy for component semantics. | Chapter 6 Semantic Integrity in Component Based Development Page Building Reliable Component-based Systems Chapter 6 - Semantic Integrity in Component Based Development Overview Introduction General Issues of Semantic Concern Levels of Formalism for Semantic Specifications Phases in a Component’s Life A Taxonomy for Component Semantics Page Building Reliable Component-based Systems Chapter 6 - Semantic Integrity in Component Based Development Introduction The specification of an interface: is partly syntactic, partly semantic The semantic component properties are expressed: using invariants for the component as a whole contracts expressed through pre- and postconditions, for each operation Page Building Reliable Component-based Systems Chapter 6 - Semantic Integrity in Component Based Development Specification Levels Levels of a component specification: Syntax: includes specifications on the programming language level. Behavior: relates to contracts. Synchronization: . | Chapter 6 Semantic Integrity in Component Based Development Page Building Reliable Component-based Systems Chapter 6 - Semantic Integrity in Component Based Development Overview Introduction General Issues of Semantic Concern Levels of Formalism for Semantic Specifications Phases in a Component’s Life A Taxonomy for Component Semantics Page Building Reliable Component-based Systems Chapter 6 - Semantic Integrity in Component Based Development Introduction The specification of an interface: is partly syntactic, partly semantic The semantic component properties are expressed: using invariants for the component as a whole contracts expressed through pre- and postconditions, for each operation Page Building Reliable Component-based Systems Chapter 6 - Semantic Integrity in Component Based Development Specification Levels Levels of a component specification: Syntax: includes specifications on the programming language level. Behavior: relates to contracts. Synchronization: describes the dependencies between services provided by a component. Quality of service: deals with quality of service. Page Building Reliable Component-based Systems Chapter 6 - Semantic Integrity in Component Based Development Contracts The semantics of an operation are described with a contract. Pre-condition: specifies the required entry conditions for activating the operation. Post-condition: specifies the exit conditions guaranteed by the operation at the end of its execution, provided the pre-condition was satisfied at the entry. The outcome in case the pre-condition was not satisfied is explicitly left undefined. Page Building Reliable Component-based Systems Chapter 6 - Semantic Integrity in Component Based Development Required and Provided Interfaces To be composable solely on the basis of its specification, a component needs to be equipped with: Explicit declarations of functionality, synchronization and quality required properties provided properties Component .