Department of Informatics, UC Irvine SDCL Collaboration Laboratory Software Design and sdcl.ics.uci.edu 1 Informatics 121 Software Design I Lecture 4 Duplication of course material for any commercial purpose without the explicit written permission of the professor is prohibited.

Department of Informatics, UC Irvine SDCL Collaboration Laboratory Software Design and sdcl.ics.uci.edu 2 Intermezzo: what experts do Experts prefer to work with others Experts prefer simple solutions Experts look around Experts focus on the essence

Department of Informatics, UC Irvine SDCL Collaboration Laboratory Software Design and sdcl.ics.uci.edu 3 Discussion There will be discussion next Monday and Wednesday Please join your designated discussion Note: location of Wednesday 10:00-10:50 discussion has been changed to MTSB 118

Department of Informatics, UC Irvine SDCL Collaboration Laboratory Software Design and sdcl.ics.uci.edu 4 Grace Hopper

Department of Informatics, UC Irvine SDCL Collaboration Laboratory Software Design and sdcl.ics.uci.edu 5 Today Design cycle Design practice Design studio 1 continued

Department of Informatics, UC Irvine SDCL Collaboration Laboratory Software Design and sdcl.ics.uci.edu 6 Four types of software design satisfactory experience plan for realization change in the world what is it to accomplish? how does one interact with it? what is its conceptual core? what are its implementation details? application design interaction design architecture design implementation design

Department of Informatics, UC Irvine SDCL Collaboration Laboratory Software Design and sdcl.ics.uci.edu 7 Design cycle analyzeevaluate synthesize

Department of Informatics, UC Irvine SDCL Collaboration Laboratory Software Design and sdcl.ics.uci.edu 8 Design cycle analyzeevaluate synthesize goals constraints assumptions decisions ideas

Department of Informatics, UC Irvine SDCL Collaboration Laboratory Software Design and sdcl.ics.uci.edu 9 Design cycle at the macro level: design process analyzeevaluate synthesize goals constraints assumptions decisions ideas

Department of Informatics, UC Irvine SDCL Collaboration Laboratory Software Design and sdcl.ics.uci.edu 10 Design process A design process represents a planned course of action as to how to tackle a design problem to arrive at a design solution – where to focus effort – what methods to use – whom to involve A design process may be defined up-front in its entirety, or defined in increments as the design project unfolds

Department of Informatics, UC Irvine SDCL Collaboration Laboratory Software Design and sdcl.ics.uci.edu 11 Waterfall requirements phase design phase implementation phase testing phase

Department of Informatics, UC Irvine SDCL Collaboration Laboratory Software Design and sdcl.ics.uci.edu 12 Waterfall as a design process satisfactory experience plan for realization change in the world what is it to accomplish? how does one interact with it? what is its conceptual core? what are its implementation details?

Department of Informatics, UC Irvine SDCL Collaboration Laboratory Software Design and sdcl.ics.uci.edu 13 Agile Our highest priority is to satisfy the customer through early and continuous delivery of valuable software. Welcome changing requirements, even late in development. Agile processes harness change for the customer's competitive advantage. Deliver working software frequently, from a couple of weeks to a couple of months, with a preference to the shorter timescale. Business people and developers must work together daily throughout the project. Build projects around motivated individuals. Give them the environment and support they need, and trust them to get the job done. The most efficient and effective method of conveying information to and within a development team is face-to-face conversation. Working software is the primary measure of progress. Agile processes promote sustainable development. The sponsors, developers, and users should be able to maintain a constant pace indefinitely. Continuous attention to technical excellence and good design enhances agility. Simplicity—the art of maximizing the amount of work not done—is essential. The best architectures, requirements, and designs emerge from self-organizing teams. At regular intervals, the team reflects on how to become more effective, then tunes and adjusts its behavior accordingly.

Department of Informatics, UC Irvine SDCL Collaboration Laboratory Software Design and sdcl.ics.uci.edu 14 Agile as a design process satisfactory experience plan for realization change in the world what is it to accomplish? how does one interact with it? what is its conceptual core? what are its implementation details?

Department of Informatics, UC Irvine SDCL Collaboration Laboratory Software Design and sdcl.ics.uci.edu 15 Other life cycle models Extreme programming Rapid prototyping Spiral model Iterative development Rational unified process Synchronize-and-stabilize …

Department of Informatics, UC Irvine SDCL Collaboration Laboratory Software Design and sdcl.ics.uci.edu 16 Choosing a software life cycle Choosing a software life cycle is choosing a design process One has to make sure the design process matches the nature of the design problem One has to make sure to remain flexible in adjusting the design process when the project so warrants

Department of Informatics, UC Irvine SDCL Collaboration Laboratory Software Design and sdcl.ics.uci.edu 17 Realistic design process satisfactory experience plan for realization change in the world what is it to accomplish? how does one interact with it? what is its conceptual core? what are its implementation details?

Department of Informatics, UC Irvine SDCL Collaboration Laboratory Software Design and sdcl.ics.uci.edu 18 Backtracking is inevitable satisfactory experience plan for realization change in the world what is it to accomplish? how does one interact with it? what is its conceptual core? what are its implementation details?

Department of Informatics, UC Irvine SDCL Collaboration Laboratory Software Design and sdcl.ics.uci.edu 19 Minimize backtracking satisfactory experience plan for realization change in the world what is it to accomplish? how does one interact with it? what is its conceptual core? what are its implementation details? Strive to minimize backtracking more than absolutely necessary Strive to minimize backtracking later than absolutely necessary

Department of Informatics, UC Irvine SDCL Collaboration Laboratory Software Design and sdcl.ics.uci.edu 20 Routine, adaptive, and original design projects high low complexity highlow familiarity routine adaptive original

Department of Informatics, UC Irvine SDCL Collaboration Laboratory Software Design and sdcl.ics.uci.edu 21 French fries and mayonaise

Department of Informatics, UC Irvine SDCL Collaboration Laboratory Software Design and sdcl.ics.uci.edu 22 Design work Design work represents the individual or collaborative activity of engaging with a design project at a detailed level – thinking – articulating context – analyzing alternative ideas – identifying constraints – making decisions – setting goals – …

Department of Informatics, UC Irvine SDCL Collaboration Laboratory Software Design and sdcl.ics.uci.edu 23 current decisionexplored idea Opportunistic versus rationalistic design work unexplored idea

Department of Informatics, UC Irvine SDCL Collaboration Laboratory Software Design and sdcl.ics.uci.edu 24 Mixed opportunistic and rationalistic design work current decisionexplored idea unexplored idea

Department of Informatics, UC Irvine SDCL Collaboration Laboratory Software Design and sdcl.ics.uci.edu 25 Backtracking current decisionexplored idea unexplored ideaprevious decision

Department of Informatics, UC Irvine SDCL Collaboration Laboratory Software Design and sdcl.ics.uci.edu 26 Backtracking current decisionexplored idea unexplored ideaprevious decision

Department of Informatics, UC Irvine SDCL Collaboration Laboratory Software Design and sdcl.ics.uci.edu 27 Simultaneous exploration current decisionexplored idea unexplored idea

Department of Informatics, UC Irvine SDCL Collaboration Laboratory Software Design and sdcl.ics.uci.edu 28 Putting it all together what is it to accomplish? how does one interact with it? what is its conceptual core? what are its implementation details? application design interaction design architecture design implementation design analyzeevaluate synthesize goals constraints assumptions decisions ideas

Department of Informatics, UC Irvine SDCL Collaboration Laboratory Software Design and sdcl.ics.uci.edu 29 French fries and mayonaise

Department of Informatics, UC Irvine SDCL Collaboration Laboratory Software Design and sdcl.ics.uci.edu 30 Design studio 1 Your client is massbroadcast.com, a new company that seeks to enable organizations to reach out to a broad audience with a pre-determined message – via phone, text, instant message, Hangouts, Skype, and other media. The company plans to make money from clients who seek to advertise their products. Being altruistic, however, the company also wants to offer support for emergency alerts. The company has sought you out, because you are an excellent designer. All of the software design is in your hands.

Department of Informatics, UC Irvine SDCL Collaboration Laboratory Software Design and sdcl.ics.uci.edu 31 Design studio 1 As a team, provide a design document that addresses the massbroadcast.com design task You should primarily focus on application design and provide a well-motivated set of decisions regarding what the application is to accomplish – generically – specifically In addition, please highlight three goals and three ideas each for interaction design and architecture design

Department of Informatics, UC Irvine SDCL Collaboration Laboratory Software Design and sdcl.ics.uci.edu 32 Design studio 1 Due October 15 at the beginning of class – bring one printed copy of your document Your group will remain the same as announced in your discussion

Department of Informatics, UC Irvine SDCL Collaboration Laboratory Software Design and sdcl.ics.uci.edu 33 Design studio 1 Due October 15 at the beginning of class – bring one printed copy of your document Your group will remain the same as announced in your discussion If you are attending Grace Hopper, come talk to me after class for one minute

Department of Informatics, UC Irvine SDCL Collaboration Laboratory Software Design and sdcl.ics.uci.edu 34 Design studio 1 Feasibility Desirability Understandability Innovativeness Completeness