Dating design patterns pdf
Java Ranch has a brand new forum, Programming Diversions! This is a place to come to in order to have some fun and to flex a bit of the ol' grey matter.
As a new feature of the Java Ranch Newsletter, and to go along with our new Programming Diversions forum, we will be offering a monthly programming puzzle.
Here we now present to you the first of hopefully many such puzzles. Given any N X N grid of letters (where N xbcbdjwgpmpcfsh avijureeroltfha bdsheriffnamnev lsuraibvoikoist iakpffrsngtoshr zhdanosourzsrea eicnuludnexerwn rednetrabvasbec mldoarahcdwyvrh auyjvroosendetl pkypuiaciornede sitemapvitralsv rafnopekaminiui umlksreyejmlpir pgetwdmpevitood javaranch moose bartender sheriff drivel reviews uml threads jdbc roundup This article is the third of a series which laments the bloated and unmaintainable state of so many J2EE web applications and looks at ways to keep web applications small, simple and flexible.
The series uses the author's Friki software as a case study, and discusses ways to design and build a powerful, flexible and usable web application in less space than a typical gif image.
This article continues the coding process begun last time, and finally starts working on real user requirements.
On the way it helps take the effort out of rebuilding and re-running tests whenever anything changes.
If you've read the first and second articles, you should be aware that the aim of this project is to develop a small, simple and understandable "Wiki" (editable web site) application.We've considered and decided to defer the relatively heavy decision of how to store and retrieve pages by introducing a Java interface, decided on and implemented a simple "template" system to display pages, and are building a supporting test suite as we go along.Before we continue, I'd like to remind everyone of what our "customer" wants.For the purposes of this article, our customer says we will be "done" when we have a Java web application in which: By now, you should know that we start each new feature by writing a test for it, so the questions should perhaps rather be "what do we test next? Whichever way you look at it, this is still a tough choice.If we want to make real progress toward our customer's goals, we need to start delivering software which meets those goals.So far, all we have is a repository interface and a template engine, neither of which is mentioned in the list. In this case I'm going to recommend that we start by choosing the easiest to test.There are lots of ways of deciding what to do next. The idea behind starting with the easiest is that the customer goals are all tangled together.Perhaps simply do them in the order they are written in. The more we can remove from the tangle, the simpler the rest will become.With any luck, by the time we get to the hard tasks, so much will already have been removed that they will be easier, too.The idea behind starting with the easiest to test is that until we have written a test, we can't start writing code, and I want to start writing real code as soon as possible.Using this approach (often known informally as "pick the low-hanging fruit") can be suitable at the start of a new project or large single change, where there are several inter-related requirements which all need to be met for anything to work at all. This approach can become dangerous as soon as something has been delivered which the customers/users can try themselves.