1333 Project• a simulation of reality:– building a substantial system– in groups of 3 or 4 people • "three-tier" system for any application you like• 3 major pieces– graphical user interface ("presentation layer")– processing in the middle ("business logic")– storage / data management• examples: many web-based services–Amazon, Ebay, other web stores– news, information services, bots– email, chat, ...• your project:– make something of roughly this structure– but smaller, simpler, defined by your interestsGetting started• right now– think about potential projectstalk to TA's, bwk; look at previous ones; look around you– form a group of 3 or 4• by Wed Mar 9 meet with bwk (earlier is better)– to be sure it's generally ok• Fri Mar 11: design document draft (before break)–~3 pages of text, pictures, etc.–overviewproject name / title, short paragraph on what it isnames, email addresses, primary role(s)list one person as project manager, acts as contact–components & interfacesmajor pieces, how they fit togethermajor design choicesweb vs. standalone, languages, tools, environment, …– schedule–risks• not frozen, but should be your best guess based on significant thought and discussion – we are happy to talk about your ideas• don't throw it together at the last minute – all components of the project are graded2Project proposal• discussion by Wed Mar 9 (earlier is good)– discuss project with bwk to be sure it's generally ok• design document draft Fri Mar 11 (before break)–~3 pages of text, pictures, etc.• overview– a short paragraph on what it is– project name / title– people names, email addresses, primary role(s)– list one person as project manager, acts as contact• components & interfaces– major pieces, how they fit together– major design choicesweb vs. standalone, languages, tools, environment, …• schedule• risks• these are not binding commitments but should be your best guess based on significant thought and discussion among team members– we are happy to talk about your ideas• don't throw it together at the last minute – all components of the project are gradedProcess: organizing what to do• use an orderly process or it won't work• this is NOT a process:– talk about the software at dinner–hack some code together– test it a bit– do some debugging– fix the obvious bugs– repeat from the top until the semester ends• classic "waterfall" model: a real processspecificationrequirementsarchitectural designdetailed designcodingintegrationtestingdelivery• this is overkill for 333• however, some process is essential …3COS 333 informal process• conceptual design– roughly, what are we doing?– blackboard sketches• requirements definition ("what")– gather ideas about what it should do– specify with written docs, prototypes, scenarios– potential users, competitive analysis, prototyping– this should not change much once you're startedit's too hard to hit a moving target• architecture / design ("how")– map out structure with design diagrams, prototypes– explore options & alternatives on paper– partition into major subsystems– specify interactions between subsystemsinterfaces, information flow, control flow– decide pervasive design issueslanguage, environment, storage, error handling– make versus buy decisions taken here[aside on what you can use from elsewhere]• implementation ("what by when")– deliver in stages, each of which is complete, workingwhat will be in each release?– test as you go: easy to break => lower gradeMake versus buy• you can use components and code from elsewhere– copy or adapt open source• design has to be your own• so does selection and assembly of components• so does the bulk of the work• it's fine to build on what others have done– identify what you have used, where it came from4Interfaces• the boundary between two parts of a program• a contract between the two parts• what are the inputs?• what are the outputs?• what is the transformation?• who manages resources?– especially memory–shared state• critical thing is to hide design decisions behind interfaces, so they can be changed later without affecting the rest of the program– data representations and formats– what database system is being used (if any)– specific algorithms• "I wish we had done interfaces better" is one of the most common comments– less often: "We thought hard about the interfaces so it was easy to change things without breaking anything."Deciding what to do• formal processes are nice, but you still have to do a lot of thinking and exploring informally• do this early, so you have time to let ideas gel• make big decisions first, to narrow the range of uncertainty later– "large grain" decisions before "small grain" (McConnell)– web based or standalone? Unix or Windows or Mac?build the GUI in Java or VB or .NET or ...?what kinds of windows will be visible?what do individual screens and menus look like?– Java or PHP or Perl or C# or ...?• think through decisions at each stage so you know enough to make decisions at next stage• this is more iterative than this might imply– don't make binding decisions until you are all fairly comfortable with them– what do users see and do? scenarios are very helpful (storyboards)sketches of screen shotsdiagrams of how information, commands, etc., will flow5Other ways to think about it• "elevator pitch"– what would you say if you were alone in an elevator with Bill Gates for 60 seconds?– attention-grabbing description– a paragraph without big words but good buzzwords• 5-7 slides for a 5-10 minute talk– what would be the titles and 2-3 points on each slide?• 1 page advertisement– what would be the main selling points?– what would your web page look like?• talk/demo outline– how would you organize a talk and demo to give at the end of the semester?– what would you want working for the demo?• business plan– how would you pitch it to an angel or venture capitalist?what does it do for who?who would want it?what's the competition?what are the stages of evolution or major releases?• job talk / interview – what did we do that's really cool?Things to keep in mind• project management– everyone has to pull together– someone has to be in charge• architecture– how do the pieces fit together?– make it work like the product of a single