How to build my own Java Math library?

Building website for math students, first-time programmer, need some guidance.

• Building website for math students, first-time programmer, need guidance. I posted http://ask.metafilter.com/223769/What-are-the-most-marketable-computerprogramming-skills-in-the-Seattle-job-market a month ago regarding learning programming after an MA in Math. I finished Think Python in about a month and wrote code to solve virtually all the exercises (good exercises), but accidentally sudo rm'ed them from the Unix shell, so I lost all but three or four programs. I'm still disappointed about this, but I still have code where I programmed a game of N-player tag, and simulated (Monte Carlo) probabilities of various Poker hands, correct to .001. Right now I'm halfway through a 600-page book on Java (Schildt's intro book; exercises are dull). I finally have an idea of a real project for myself, as opposed to these toy exercises. I'd like to build a website for my (college) math students with games and tests to incentivize and improve their performance. It'd be private (they'd have to log in with a password), they'd select their own avatar and name, their scores and performance will be recorded, and they'll compete against one another in various ways. It'll be entertaining and fun, with a nice GUI. I'd like to get a shell up before I start making the interface fancy, but I'm mildly ambitious about the end product. It'd also be a general "course webpage", with accessible private information such as grades, as well as public announcements such as course policies and announcements. I think this could go somewhere, but I've never done this before. What should I know and study besides Java and Python with an eye towards this project? Is it too early in my development, am I moving too fast, etc.?

• Answer:

  The point is to gain programming experience, and make those novice mistakes and learn what they are, so I can avoid them in the future. The thing is that in many cases you wouldn't necessarily realize you're making mistakes -- instead of learning from them, you'd just be ingraining bad habits. You can learn a lot more about good coding practices by working closely with a well-written framework than by floundering around on your own. If you're just looking for an excuse to play around and write some code, that's great, reinvent all the wheels you want. But you're talking about exposing real student data, including grade information -- until you have a solid grounding in web security and common code exploits, this is a Very Bad Idea Indeed. Not to mention the satisfaction of building something for myself and not just appropriating someone else's work. Using frameworks isn't "appropriating someone else's work," it's getting past the boilerplate code so you can focus on the parts you really care about. It's also a way of ensuring that the boilerplate actually works, has been thoroughly tested, and is reasonably secure, so you're not building on a foundation of sand. In a very real sense, no software is written from scratch anymore: you're always dependent on other people's work (including everything from frameworks to engines to code library dependencies to the server environment in which your code exists.) 80% of being a good developer is making good decisions about which code to depend on, and when it's better to use existing battle-tested code versus building from scratch. (Further reading: "build versus buy," "not invented here syndrome"). I don't want to use anyone else's interface; I want to use my own. The college I teach at has a math course management system popular with a few instructors, but it strikes me as clunky and not nice to look at. All course management systems include a way to customize the interface. Some are more flexible at this than others -- if you have specific interface needs, determining whether a given framework can support them is an important part of the selection process. As a secondary point, good interface design is hard; it's a skillset separate from but as difficult as -- and as time-consuming as -- the nuts-and-bolts writing of code. Your planned process (write code first and bolt an interface on after the fact) is pretty much one of the classic mistakes-you-won't-know-you're-making. (It's also one made by far too many professional developers, unfortunately: it's very very easy to slip into designing your interface around the way your code works as opposed to designing your code around the way your interface should work -- I'm primarily an interface designer but even I catch myself doing this sometimes when I'm in a code-writing headspace.)