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An Introduction to UML & Modeling Resources Using UML. Rahul Shah EE249 Discussion Sept. 25, 2001. Talk Outline. An introduction to UML Different views in UML Examples from PicoRadio UML documentation Discussion of Bran Selic’s paper, “A generic framework for modeling resources with UML”.
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An Introduction to UML & Modeling Resources Using UML Rahul Shah EE249 Discussion Sept. 25, 2001
Talk Outline • An introduction to UML • Different views in UML • Examples from PicoRadio UML documentation • Discussion of Bran Selic’s paper, “A generic framework for modeling resources with UML”
Project Phases Inception Elaboration Construction Transition Process Components Requirements capture Analysis & Design Implementation Test The Development Process }UML
Unified Modeling Language • Object oriented modeling language • Intended to model discrete systems such as software, firmware or digital logic “Models are used to capture and precisely state requirements and domain knowledge so that all stakeholders may understand and agree on them.” (Rumbaugh, Jacobson & Booch)
UML Views • Structural: things in the system and their relationship to other things • Class diagrams • Use case diagrams • Component diagrams • Dynamic: system behavior over time • Statechart diagram • Activity diagram • Sequence diagram • Model management, others
Class Diagram† †PicoRadio UML documentation
Use Case Diagram† †PicoRadio UML documentation
Activity Diagram† †PicoRadio UML documentation
Sequence Diagram† †PicoRadio UML documentation
A Generic Framework for Modeling Resources With UML Bran Selic IEEE Computer, June 2000.
Quantitative Analysis • Schedulability analysis • Deterministic technique • Good for hard real-time systems • Performance analysis • Probabilistic characterization • Good for soft real-time systems
Layered interpretation (realization mappings play the role of QoS contracts) QoS Contracts Peer interpretation
Composition Associations Association Class Aggregation UML Model of QoS Contracts
Generalization Management of Resources
Realization Mapping Realization relationship
QoS Analysis • Compare the required QoS with the offered QoS • The offered QoS should exceed the required QoS • Aggregated QoS characteristics can complicate the analysis: • Different characteristics combine in different ways • Resources are often shared
Conclusions • Models are useful to predict and quantify performance of software without actual construction • Incorporating a generic QoS framework in UML helps us in analyzing software models • UML is an industry standard, thus a common base to develop new techniques for analysis