Design Patterns #3 & MidTerm Review Reid Holmes Lecture 13 - - PowerPoint PPT Presentation

Material and some slide content from: - GoF Design Patterns Book Design Patterns #3 & MidTerm Review Reid Holmes Lecture 13 - Thursday October 28 2010.

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MidTerm Review Intended Learning Outcomes: ‣ “Critique an existing architecture or design.” ‣ “Differentiate how various architectural styles and ‣ design patterns enhance and degrade functional- and non-functional properties.” “Generate and justify and architecture and/or ‣ design given a collection of requirements.” “Produce and present concise and unambiguous ‣ architecture and design descriptions.” “Create and implement an architecture and ‣ design, refining it into a complete system.” REID HOLMES - SE2: SOFTWARE DESIGN & ARCHITECTURE

ILO 1: Critique “Critique an existing architecture or design.” ‣ So what is architecture? ‣ ‣ REID HOLMES - SE2: SOFTWARE DESIGN & ARCHITECTURE

ILO 1: Critique “Critique an existing architecture or design.” ‣ Why is architecting software hard? ‣ What has improved complexity? ‣ ‣ REID HOLMES - SE2: SOFTWARE DESIGN & ARCHITECTURE

ILO 1: Critique “Critique an existing architecture or design.” ‣ Example: ‣ Given GWTs architecture, what is one benefit of 2nd ‣ generation web apps compared to GWT-based web-apps? REID HOLMES - SE2: SOFTWARE DESIGN & ARCHITECTURE

ILO 2: Differentiate “Differentiate how various architectural styles and ‣ design patterns enhance and degrade functional- and non-functional properties.” What is an architectural style? ‣ What is a design pattern? ‣ ‣ REID HOLMES - SE2: SOFTWARE DESIGN & ARCHITECTURE

ILO 2: Differentiate “Differentiate how various architectural styles and ‣ design patterns enhance and degrade functional- and non-functional properties.” Abstraction: ‣ Separation of concerns: ‣ ‣ REID HOLMES - SE2: SOFTWARE DESIGN & ARCHITECTURE

ILO 2: Differentiate “Differentiate how various architectural styles and ‣ design patterns enhance and degrade functional- and non-functional properties.” FPs: ‣ NFPs: ‣ Covered Styles: client-server, main / subroutine, OO, VM, ‣ layered, batch-sequential, pipe & filter, rule-based, blackboard, event-based, publish / subscribe, interpreter, mobile code, peer to peer. Covered Patterns: singleton, abstract factory, builder, ‣ proxy, facade, decorator, composite, visitor. REID HOLMES - SE2: SOFTWARE DESIGN & ARCHITECTURE

ILO 2: Differentiate “Differentiate how various architectural styles and ‣ design patterns enhance and degrade functional- and non-functional properties.” Security: ‣ Security Arch Principles: ‣ ‣ REID HOLMES - SE2: SOFTWARE DESIGN & ARCHITECTURE

ILO 3: Generate and Justify “Generate and justify and architecture and/or ‣ design given a collection of requirements.” Analysis vs design: ‣ Example: Apply your knowledge of architectural ‣ styles to architect a system that allows users to dynamically enter text commands that the system will then carry out. Provide a component diagram. Justify your selection of architectural style. REID HOLMES - SE2: SOFTWARE DESIGN & ARCHITECTURE

ILO 3: Generate and Justify “Generate and justify and architecture and/or ‣ design given a collection of requirements.” Example: ‣ DatabaseLayer layer = DatabaseLayer.getInstance(); ‣ What design pattern is being demonstrated above. Why is ‣ this pattern used? What visibility is applied to constructors in this pattern? Why? REID HOLMES - SE2: SOFTWARE DESIGN & ARCHITECTURE

ILO 4: Produce and Present “Produce and present concise and unambiguous ‣ architecture and design descriptions.” Alternative views: ‣ ‣ REID HOLMES - SE2: SOFTWARE DESIGN & ARCHITECTURE

ILO 4: Produce and Present “Produce and present concise and unambiguous ‣ architecture and design descriptions.” Example: ‣ - Create a component diagram for an event-based ‣ system that has a Producer component and a Consumer component connected to an event bus. ‣ REID HOLMES - SE2: SOFTWARE DESIGN & ARCHITECTURE

ILO 5: Create and Implement “Create and implement an architecture and ‣ design, refining it into a complete system.” This is really about the project. ‣ REID HOLMES - SE2: SOFTWARE DESIGN & ARCHITECTURE