8 September 2010

Your Architecture First level diagram: how components fit together

What Architectures Do You Know?

Software Architecture Goals  Extensibility: adding new features Tradeoff of generality and time How might it be extended?  Changeability: requirements changes  Simplicity: ease of understanding and implementing  Efficiency: speed and size

Key Characteristics  Cohesion degree to which communication takes place within the module  Coupling degree to which communication takes place between modules  Min-max problem: minimize coupling while maximizing cohesion

Examples  Role-playing game Decompose into 4 modules: environment, game control, participants and artifacts High cohesion and high coupling ○ When two characters meet, all 4 modules are involved  Personal finance application Decompose into user activities: accounts, bill playing, loans, investments Low cohesion and high coupling ○ Accounts are pretty independent ○ Loan payment would involve the first 3 modules

Key Development Tools  Revision Management System  IDE  Wiki  API Documentation Extraction

Documentation Principles  Need to reflect changes Not just change, but CAPTURE change Version control  Need to keep all documents synchronized Only say it once  Danger of shared ownership: If many own, no one owns  Practical consideration: Responsibility vs. authority