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Watermelon Reporting
This is what Wikipedia writes about the watermelon: The Watermelon (Citrullus lanatus (Thunb.), family Cucurbitaceae) can be both the fruit and the plant of a vine-like (scrambler and trailer) plant originally from southern Africa, and is one of the most common types of melon. [...] The watermelon fruit, loosely considered a type of melon (although not in the genus Cucumis), has a smooth exterior rind (green, yellow and sometimes white) and a juicy, sweet interior flesh (usually pink, but sometimes orange, yellow, red and sometimes green if not ripe). Watermelon (Citrullus lanatus (Thunb.), family Cucurbitaceae) can be both the fruit and the plant of a vine-like (scrambler and trailer) plant originally from southern Africa, and is one of the most common types of melon. This flowering plant produces a special type of fruit known by botanists as a pepo, a berry which has a thick rind (exocarp) and fleshy center (mesocarp and endocarp); pepos are derived from an inferior ovary, and are characteristic of the Cucurbitaceae. The watermelon fruit, loosely considered a type of melon (although not in the genus Cucumis), has a smooth exterior rind (green, yellow and sometimes white) and a juicy, sweet interior flesh (usually pink, but sometimes orange, yellow, red and sometimes green if not ripe). For my metaphor, I’ll use the one with red flesh but orange and yellow would work too. I think most of us experienced the phenomenon when the project status is red but is getting greener and greener when climbing the management ladder. The project’s core is red but for the management it has a nice green paring, so it looks like a watermelon. This is why I call this phenomenon Watermelon Reporting. But why are we creating such reports and how can we avoid it? Why? The bearer of bad news already had a bad time in the ancient world. If he was lucky, they gave him the chop but in other cases they simply chopped his head of. This hasn’t changed until now but fortunately only in a figurative sense. Some bosses aren’t interested that there are problems with a project in their responsibility because if they know about it, they are in charge. So what do they do to avoid incurring the wrath of their boss ? They tweak the project status just a bit and the melon starts growing. Another reason could be that nobody wants to be in the focus of management, thus they embellish the project status in the hope that everything turns for the better. And as we all know hope is the last to die. In the end the result is the same.. Eventually the overripe melon bursts and there is no rescue for the project anymore. How to avoid it? The answer is easy: Transparency, transparency and transparency. If there is no way to hide the current status the watermelon can’t grow. Fortunately Scrum and other agile frameworks provide tools like burndown charts and backlogs to help the team with their transparency. But there are also tools like dashboards or kanban boards to do this job, but this will be the subject of one of my next blog posts. Conclusion The nuts and bolts of any project are transparency. If the project status is transparent, the watermelons can’t arise. If anybody is able to get the information, it will be difficult to hide something.
August 8, 2011
by Marc Löffler
· 9,301 Views
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What's your favorite Agile Game?
I recently attended the Agile Coach Gathering UK in Bletchley Park near London. I met a lot of interesting people, had some great talks and discussion and learned a ton. As the gathering was an open space conference I also proposed a session with the topic “What’s your favorite Agile Game?”. The goal was to collect some great games I could play in my next Scrum or Kanban trainings. A fun fact of this session was that everybody found out that we knew more games than we expected before. We came up with the following list of games. P&Q P&Q is not really a game but a collaborative process. The P&Q is a simple process which makes just two things; “P’s” and “Q’s.” The objective of the exercise is to make a decision as to how to best maximize the profit of this process. A more precise description can be found here. The XP Game The XP Game if one of the oldest and most known games in the agile community. The XP Game is a playful way to familiarize the players with some of the more difficult concepts of the XP Planning Game, like velocity, story estimation, yesterday’s weather and the cycle of life. A detailed description of the game can be found here. There are several variations of the game but my personal favorite is the LEGO(c) XP Game. I’m a big LEGO(c) fan and use any excuse to play with those bricks. Here are some photos of a team playing this game. I highly recommend this game to any team new to agile. Scrum from hell Scrum from hell is more a role play than a game and simulates a dysfunctional daily scrum meeting. It is always fun observing the participants playing the roles. The duration of this game is only 15 minutes and a must for any Scrum training. A description of this game can be found here. The communication game As I don’t have the real name of this game I just named it this way. This game is all about communication. The following roles are part of this game: Client Business Analyst Architect Developer In the first round nobody is allowed to speak. The client describes his requirements as written document to the business analyst and the BA passes on what he did understand to his architect and finally to the developer. As the info arrives at the developer he starts to build what he understood. When he is ready the review starts. In most cases the client don’t get what he has expected. In the second round everybody is allowed to speak and ask questions. In most cases this leads to a product the client asked for. If you have some more info about this game or even some artifacts, leave a comment. The ballpoint game This game is also one of my favorites. It’s about passing as many balls as possible between the players during a given time. With this game the concept of iterations/sprints and retrospective are explained. I already posted a more detailed description of this game in my blog which can be found here. Making paper hats In this game the concepts of velocity and iteration/sprint are explained. The main goal is to map the planned amount of paper hats with the actual amount. This game can also be played by blowing balloons or any other simple task. The customer in this game tries to push the development team to build as many paper hats as possible during an iteration. The result is that most of the build paper hats are useless as the quality is quite low. The customer keeps pushing until the team realizes that they are only able to build x paper hats during one iteration in the requested quality. Now the team knows his own velocity and is able to negotiate with the customer on the maximum number of paper hat. Another outcome of this game is that the player realize that quality is not negotiable. If someone has a link to a more precise description, please leave a comment. Other games There are a lot of agile games online. During the session I suggested the following places to search for additional games: http://www.tastycupcakes.com – This is a great resource for agile games. I highly recommend to have look here http://www.kanbangames.net – On this page you’ll find some games explaining the concepts of kanban and lean software development. AgileGames on Google Groups – If you’re interested in the newest games or want to discuss about games, this is the place to go. Come and join our group. If you have any other resources or any other addition to this blog post, feel free to leave a comment.
July 4, 2011
by Marc Löffler
· 9,544 Views
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Agile Chronicles #5: Acceptance Criteria & Punting
The Agile Chronicles is a set of articles documenting my experiences using an Agile process (Scrum) in software development on my current Flex project. Part 1 – Stressful Part 2 – Code Refactoring Part 3 – Branch Workflow Part 4 – POC, Strategy, and Design Challenges Part 5 – Acceptance Criteria & Punting Part 6 – Tools, Extra Merge Day, and Postponed Transitions Part 7 – Bugs, Unit Testing, and Throughput Part 8 – Demo, Burnout, and Feature Juggling Part 9 – Scope Creep Part 10 – Conclusions This entry is about defining what the acceptance criteria for user stories are so you can confirm you really did complete them during the UAT at the end of the sprint. It’s also about determining when you should abort a task that is taking too much time. Acceptance Criteria – Is the User Story Really Done? Each of our 2 week sprints include a set of user stories each developer must complete by the end of the sprint. We naturally overload our selves to ensure we have an added sense of urgency, additional user stories to tackle of we encounter a major roadblock to completing a particular story, and to clearly articulate what is priority in a bigger picture. On the 2nd Friday, we do our UAT (User Acceptance Testing). The way we do it is go through the latest build from SVN’s trunk, and collectively try to do each of the user stories. Like, “User story #32 says, ‘The user can type in their user name and password, and if they are a registered user, they will be taken to the main screen’”. If this happens, that user story is complete, we get confirmation from the client as such, and move to the next. It’s not always that black and white, though. Some user stories, even if still simple, have certain acceptance criteria associated with them. The first, and only, acceptance criteria we used in the beginning was what I just described; clearly written user stories that are easily testable. As the application grows in complexity, and certain things are assumed to go along with the user story, we’ve had to add some acceptance criteria to certain user stories. For example, even though in Sprint #1 I did in fact get the login working, none of the fonts were correct, and the alignment on some of the graphics were off. This was obvious to all, including me. Did this mean that I still completed the user story? Yes. “Yes” according to who? The client. Therefore, user story acceptance criteria seems client driven. Some clients, those not like the kind agencies have, are more functionality oriented and they don’t notice subtle design inconsistencies all the time like Verdana vs. Helvetica LT 57 Condensed. Others are more about design, and less about functionality. Some are both. Our particular client is more on the functionality side of the fence because we are working with them to complete functionality; it’s not just us working alone. That said, it still seems like each user story has it’s own unique acceptance criteria. This isn’t always easy to do, either. You really need to announce the assumptions because if you don’t, one thing you can count on is the following Friday’s UAT pointing them out; either they were assumed, and are in there, or weren’t, and aren’t. Sometimes you don’t know what those assumptions are, and thus, yet again one of the validations of using iterative development in short sprints; getting the functionality done quickly and in front of the client so they can see those assumptions. Regardless, this is something our project manager and client have been doing every Monday, both during and after, our planning session. Adding more implied functionality to a user story implies it could be more challenging, thus more work involved, and thus worth more points. This in turn affects how many user stories should be tackled per sprint. Punt – You’re in a downward spiral, pull up! You ever attempt to code something really hard, and not quite get there? Or worse, you keep getting close, yet every step feels like you’re only getting farther away as you start running out of ideas… or you have less time to implement your new ideas? This is what I call the downward spiral, akin to an airplane which stalled from going too high too quickly, and now is in a downward spiral. It can happen to those who compensate for lack of intelligence with willpower (me) and those who are smart, get in the zone, and never come out. I did that this sprint, badly. I had a really challenging component, a sub-task in a user story, and greatly underestimated my ability to pull it off. As the days wore on, my determination only increased. Two times I had a “flashback” to my Flash days, and thought about ways of faking it as well as having a plan B. Upon taking 10 minutes to test my Plan B three days in, I realized my Plan B wasn’t going to work either. I then started to do the math, and figure out how many days I had left in the Sprint, and how many user stories I had left to complete in those days. I was over what I should of been. In short, I was screwed. There is an old investment lesson called “cutting your losses”. It’s about recognizing that your investment in a particular company or mutual fund is bad. The company could be blatantly going downhill, and you can’t sell short for whatever reason (selling a hammer to someone, and then buying it back for less than you sold it for). So, the only option is to pull your money out before you lose more money. It’s the right business decision to do. The analogy is an alligator has bitten your arm. You can run, and lose your arm, or attempt to kick it, and hope it opens its mouth long enough for you to pull your arm out. This is usually destined to be bad because you could then lose your leg… or worse. Same with bad investments. If they are bad, pull your money out. The only thing you have to show for it is the money you saved. Same with aborting coding a component you won’t complete in a reasonable time frame. By stopping your aren’t giving up. People like me take it very personally, and perceive it as giving up. Jesse Warden doesn’t give up. I really have to change my mindset that, given enough time, I could complete it. However, there are more important things left to be done, so I put it “on hold”. Whatever bs you tell yourself to pull up out of the downward spiral will do. This is what I call punting. Punting is a play that you do in American football. If you’re on offense, your goal is to carry the ball into the opponents end zone. If you don’t get far enough after your allotted 4 downs, you’re going to be in trouble if the opponent gets the ball, and is closer to your end zone than you their’s. So, you punt; kick the ball as far as you can down towards their end zone, yet not on it, in the hopes you make them travel as far as possible back to your end zone. If for whatever reason, your team cannot take the ball to the opponents end zone by 3rd down, on the 4th, you need to make the decision: Do you go for it or do you not take the risk and end up screwing yourself if you don’t make it, and punt instead? In American Football, this can be a very complicated decision. In Agile software, not so much. Do the math; how many days / hours do you have to play with to hit the rest of your user stories? Is it worth it to you to work 12 hour days just in case your risk doesn’t pay off? It is it worth it to work 12 hour days EVEN IF you end up failing? I did the math too late this time, but won’t make that same mistake again. That’s what I’ll keep telling myself as I work this Saturday on Thanksgiving weekend, and next week as I work 12 hour days.
July 4, 2011
by James Warden
· 5,753 Views
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Eradicating Non-Determinism in Tests
An automated regression suite can play a vital role on a software project, valuable both for reducing defects in production and essential for evolutionary design. In talking with development teams I've often heard about the problem of non-deterministic tests - tests that sometimes pass and sometimes fail. Left uncontrolled, non-deterministic tests can completely destroy the value of an automated regression suite. In this article I outline how to deal with non-deterministic tests. Initially quarantine helps to reduce their damage to other tests, but you still have to fix them soon. Therefore I discuss treatments for the common causes for non-determinism: lack of isolation, asynchronous behavior, remote services, time, and resource leaks. I've enjoyed watching ThoughtWorks tackle many difficult enterprise applications, bringing successful deliveries to many clients who have rarely seen success. Our experiences have been a great demonstration that agile methods, deeply controversial and distrusted when we wrote the manifesto a decade ago, can be used successfully. There are many flavors of agile development out there, but in what we do there is a central role for automated testing. Automated testing was a core approach to Extreme Programming from the beginning, and that philosophy has been the biggest inspiration to our agile work. So we've gained a lot of experience in using automated testing as a core part of software development. Automated testing can look easy when presented in a text book. And indeed the basic ideas are really quite simple. But in the pressure-cooker of a delivery project, trials come up that are often not given much attention in texts. As I know too well, authors have a habit of skimming over many details in order to get a core point across. In my conversations with our delivery teams, one recurring problem that we've run into is tests which have become unreliable, so unreliable that people don't pay much attention to whether they pass or fail. A primary cause of this unreliability is that some tests have become non-deterministic. A test is non-deterministic when it passes sometimes and fails sometimes, without any noticeable change in the code, tests, or environment. Such tests fail, then you re-run them and they pass. Test failures for such tests are seemingly random. Non-determinism can plague any kind of test, but it's particularly prone to affect tests with a broad scope, such as acceptance or functional tests. Why non-deterministic tests are a problem Non-deterministic tests have two problems, firstly they are useless, secondly they are a virulent infection that can completely ruin your entire test suite. As a result they need to be dealt with as soon as you can, before your entire deployment pipeline is compromised. I'll start with expanding on their uselessness. The primary benefit of having automated tests is that they provide bug detection mechanism by acting as regression tests[1]. When a regression test goes red, you know you've got an immediate problem, often because a bug has crept into the system without you realizing. Having such a bug detector has huge benefits. Most obviously it means that you can find and fix bugs just after they are introduced. Not just does this give you the warm fuzzies because you kill bugs quickly, it also makes it easier to remove them since you know the bug got in with the last set of changes that are fresh in your mind. As a result you know where to look for the bug, which is more than half the battle in squashing it. The second level of benefit is that as you gain confidence in your bug detector, you gain the courage to make big changes knowing that when you goof, the bug detector will go off and you can fix the mistake quickly. [2] Without this teams are frightened to make the changes code needs in order to be kept clean, which leads to a rotting of the code base and plummeting development speed. The trouble with non-deterministic tests is that when they go red, you have no idea whether its due to a bug, or just part of the non-deterministic behavior. Usually with these tests a non-deterministic failure is relatively common, so you end up shrugging your shoulders when these tests go red. Once you start ignoring a regression test failure, then that test is useless and you might as well throw it away. Indeed you really ought to throw a non-deterministic test away, since if you don't it has an infectious quality. If you have a suite of 100 tests with 10 non-deterministic tests in them, than that suite will often fail. Initially people will look at the failure report and notice that the failures are in non-deterministic tests, but soon they'll lose the discipline to do that. Once that discipline is lost, then a failure in the healthy deterministic tests will get ignored too. At that point you've lots the whole game and might as well get rid of all the tests. Quarantine My principal aim in this article is to outline common cases of non-deterministic tests and how to eliminate the non-determinism. But before I get there I offer one piece of essential advice: quarantine your non-deterministic tests. If you have non-deterministic tests keep them in a different test suite to your healthy tests. That way you'll you can continue to pay attention to what's going on with your healthy tests and get good feedback from them. Place any non-deterministic test in a quarantined area. (But fix quarantined tests quickly.) Then the question is what to do with the quarantined test suites. They are useless as regression tests, but they do have a future as work items for cleaning up. You should not abandon such tests, since any tests you have in quarantine are not helping you with your regression coverage. A danger here is that tests keep getting thrown into quarantine and forgotten, which means your bug detection system is eroding. As a result it's worthwhile to have a mechanism that ensures that tests don't stay in quarantine too long. I've come across various ways to do this. One is a simple numeric limit: e.g. only allow 8 tests in quarantine. Once you hit the limit you must spend time to clear all the tests out. This has the advantage of batching up your test-cleaning if that's how you like to do things. Another route is to put a time limit on how long a test may be in quarantine, such as no longer than a week. The general approach with quarantine is to take the quarantined tests out of the main deployment pipeline so that you still get your regular build process. However a good team can be more aggressive. Our Mingle team puts its quarantine suite into the deployment pipeline one stage after its healthy tests. That way it can get the feedback from the healthy tests but is also forced to ensure that it sorts out the quarantined tests quickly. [3] Lack of Isolation In order to get tests to run reliably, you must have clear control over the environment in which they run, so you have a well-known state at the beginning of the test. If one test creates some data in the database and leaves it lying around, it can corrupt the run of another test which may rely on a different database state. Therefore I find it's really important to focus on keeping tests isolated. Properly isolated tests can be run in any sequence. As you get to larger operational scope of functional tests, it gets progressively harder to keep tests isolated. When you are tracking down a non-determinism, lack of isolation is a common and frustrating cause. Keep your tests isolated from each other, so that execution of one test will not affect any others. There are a couple of ways to get isolation - either always rebuild your starting state from scratch, or ensure that each test cleans up properly after itself. In general I prefer the former, as it's often easier - and in particular easier to find the source of a problem. If a test fails because it didn't build up the initial state properly, then it's easy to see which test contains the bug. With clean-up, however, one test will contain the bug, but another test will fail - so it's hard to find the real problem. Starting from a blank state is usually easy with unit tests, but can be much harder with functional tests [4] - particularly if you have a lot of data in a database that needs to be there. Rebuilding the database each time can add a lot of time to test runs, so that argues for switching to a clean-up strategy. One trick that's handy when you're using databases, is to conduct your tests inside a transaction, and then to rollback the transaction at the end of the test. That way the transaction manager cleans up for you, reducing the chance of errors[5]. Another approach is to do a single build of a mostly-immutable starting fixture before running a group of tests. Then ensure that the tests don't change that initial state (or if they do, they reverse the changes in tear-down). This tactic is more error-prone than rebuilding the fixture for each test, but it may be worthwhile iff it takes too long to build the fixture each time. Although databases are a common cause for isolation problems, there are plenty of times you can get these in-memory too. In particular be aware with static data and singletons. A good example for this kind of problem is contextual environment, such as the currently logged in user. If you have an explicit tear-down in a test, be wary of exceptions that occur during the tear-down. If this happens the test can pass, but cause isolation failures for subsequent tests. So ensure that if you do get a problem in a tear-down, it makes a loud noise. Some people prefer to put less emphasis on isolation and more on defining clear dependencies to force tests to run in a specified order. I prefer isolation because it gives you more flexibility in running subsets of tests and parallelizing tests. Asynchronous Behavior Asynchrony is a boon that allows you to keep software responsive while taking on long term tasks. Ajax calls allow a browser to stay responsive while going back to the server for more data, asynchronous message allow a server process to communicate with other system without being tied to their laggardly latency. But in testing, asynchrony can be curse. The common mistake here is to throw in a sleep: //pseudo-code makeAsyncCall; sleep(aWhile); readResponse; This can bite you two ways. First off you'll want to set the sleep time to long enough that it gives plenty of time to get the response. But that means that you'll spend a lot of time idly waiting for the response, thus slowing down your tests. The second bite is that, however long you sleep, sometimes it won't be enough. There will be some change in environment that will cause you to exceed the sleep - and you'll get false failure. As a result I strongly urge you to never use bare sleeps like this. Never use bare sleeps to wait for asynchonous responses: use a callback or polling. There are basically two tactics you can do for testing an asynchronous response. The first is for the asynchronous service to take a callback which it can call when done. This is the best since it means you'll never have to wait any longer than you need to [6]. The biggest problem with this is that the environment needs to be able to do this and then the service provider needs to do it. This is one of the advantages of having the development team integrated with testing - if they can provide a callback then they will. The second option is to poll on the answer. This is more than just looking once, but looking regularly, something like this //pseudo-code makeAsyncCall startTime = Time.now; while(! responseReceived) { if (Time.now - startTime > waitLimit) throw new TestTimeoutException; sleep (pollingInterval); } readResponse The point of this approach is that you can set the pollingInterval to a pretty small value, and know that that's the maximum amount of dead time you'll lose to waiting for a response. This means you can set the waitLimit very high, which minimizes the chance of hitting it unless something serious has gone wrong. [7] Make sure you use a clear exception class that indicates this is a test timeout that's failing. This will help make it clear what's gone wrong should it happen, and perhaps allow a more sophisticated test harness to take account of this information in its display. The time values, in particular the waitLimit, should never be literal values. Make sure they are always values that can be easily set in bulk, either by using constants or set through the runtime environment. That way if you need to tweak them (and you will) you can tweak them all quickly. All this advice is handy for async calls where you expect a response from the provider, but how about those where there is no response. These are calls where we invoke a command on something and expect it to happen without any acknowledgment. This is the trickiest case since you can test for your expected response, but there's nothing to do to detect a failure other than timing-out. If the provider is something you're building you can handle this by ensuring the provider implements some way of indicating that it's done - essentially some form of callback. Even if only the testing code uses it, it's worth it - although often you'll find this kind of functionality is valuable for other purposes too[8]. If the provider is someone else's work, you can try persuasion, but otherwise may be stuck. Although this is also a case when using Test Doubles for remote services is worthwhile (which I'll discuss more in the next section). If you have a general failure in something asynchronous, such that it's not responding at all, then you'll always be waiting for timeouts and your test suite will take a long time to fail. To combat this it's a good idea to use a smoke test to check that the asynchronous service is responding at all and stop the test run right away if it isn't. Gerard Meszaros's book, xUnit Test Patterns, contains lots of good patterns for constructing tests. You can also often side-step the asynchrony completely. Gerard Meszaros's Humble Object pattern says that whenever you have some logic that's in a hard-to-test environment, you should isolate the logic you need to test from that environment. In this case it means put most of the logic you need to test in a place where you can test it synchronously. The asynchronous behavior should be as minimal (humble) as possible, that way you don't need that much testing of it. Remote Services Sometimes I'm asked if ThoughtWorks does any integration work, which I find somewhat amusing since there's hardly any project we do that doesn't involve a fair bit of integration. By their nature, enterprise applications involve a great deal of combining data from different systems. These systems are maintained by other teams operating to their own schedules, teams that often use a very different software philosophy to our heavily test-driven agile approach. Testing with such remote systems brings a number of problems, and non-determinism is high on the list. Often remote systems don't have test system we can call, which means hitting a live system. If there is a test system, it may not be stable enough to provide deterministic responses. In this situation it's vital to ensure determinism, so it's time to reach for a Test Double - a component that looks like the remote service, but is really just a pretend version that mimics the remote system's behavior. The double needs to be setup so that provides the right kind of response in interaction with our system, but in a way we control. In this manner we can ensure determinism. Using a double has a downside, in particular when we are testing across a broad scope. How can we be sure that the double behaves in the same way that remote system does? We can tackle this again using tests, a form of test that I call Integration Contract Tests. These run the same interaction with the remote system and the double, and check that the two match. In this case 'match' may not mean coming up with the same result (due to the non-determinisms), but results that share the same essential structure. Integration Contract Tests need to be run frequently, but not part of our system's deployment pipeline. Periodic running based on the rate of the change of the remote system is usually best. For writing these kinds of test doubles, I'm a big fan of Self Initializing Fakes - since these are very simple to manage. Some people are firmly against using Test Doubles in functional tests, believing that you must test with real connection in order to ensure end-to-end behavior. While I sympathize with their argument, automated tests are useless if they are non-deterministic. So any advantage you gain by talking to the real system is overwhelmed by the need to stamp out non-determinism[9]. Time Few things are more non-deterministic than a call to the system clock. Each time you call it, you get a new result, and any tests that depend on it can thus change. Ask for all the todos due in the next hour, and you regularly get a different answer[10]. The most important thing here is to ensure that you always wrap the system clock with routines that can be replaced with a seeded value for testing. A clock stub can be set to particular time and frozen at that time, allowing your tests to have complete control over its movements. That way you can synchronize your test data to the values in the seeded clock.[11][12] Always wrap the system clock, so it can be easily substituted for testing. One thing to watch with this, is that eventually your test data might start having problems because it's too old, and you get conflicts with other time based factors in your application. In this case you can move the data, and your clock seeds to new values. When you do this, ensure that this is the only thing you do. That way you can be sure that any tests that fail are due to time-movement in the test data. Another area where time can be a problem is when you rely on other behaviors from the clock. I once saw a system that generated random keys based on clock values. This systems started failing when it was moved to a faster machine that could allocate multiple ids within a single clock tick.[13] I've heard so many problems due to direct calls to the system clock that I'd argue for finding a way to use code analysis to detect any direct calls to the system clock and failing the build right there. Even a simple regex check might save you a frustrating debugging session after a call at an ungodly hour. Resource Leaks If your application has some kind of resource leak, this will lead to random tests failing, since it's just which test causes the resource leak to go over a limit that gets the failure. This case is awkward because any test can fail intermittently due to this problem. If it isn't a case of one test being non-deterministic then resource leaks are a good candidate to investigate. By resource leak, I mean any resource that the application has to manage by acquiring and releasing. In non-memory-managed environments, the obvious example is memory. Memory-management did much to remove this problem, but other resources still need to be managed, such as database connections. Usually the best way to handle these kind of resources is through a Resource Pool. If you do this then a good tactic is to configure the pool to a size of 1 and make it throw an exception should it get a request for a resource when it has none left to give. That way the first test to request a resource after the leak will fail - which makes it a lot easier to find the problem test. This idea of limiting resource pool sizes, is about increasing constraints to make errors more likely to crop up in tests. This is good because we want errors to show in tests so we can fix them before they manifest themselves in production. This principle can be used in other ways too. One story I heard was of a system which generated randomly named temporary files, didn't clean them up properly, and crashed on a collision. This kind of bug is very hard to find, but one way to manifest it is to stub the randomizer for testing so it always returns the same value. That way you can surface the problem more quickly.
April 14, 2011
by Martin Fowler
· 6,643 Views · 1 Like
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A story about User Stories; Where do you start and what about the planning?
In this multi-part post, I’m going to share my personal experiences while working with user stories for gathering, tracking and planning requirements. It currently consists out of three parts: What are they and why do you need them? Who writes them and how do you control scope? Where do you start and what about the planning? You can also download all parts as one comprehensive PDF for easy printing or e-reading. Where do you start? Suppose that after intensive discussions and tough scoping sessions you ended up with a list of user stories and are about to start building the system. The first story not only needs to realize some particular feature, but also involves building a skeleton implementation of the system’s architecture. How do you avoid spending way too much time on plumbing and other general purpose stuff you need for the rest of the stories? The article Managing the Bootstrap Story by Jennitta Andrea addressed this challenge in more detail and offers some alternative solutions. One of these solutions is to find and define a user story with the product owner that offers minimal functionality yet still has project value. Such a story is often referred to as the backbone story because you realize the backbone of your system in it. It’s quite common to use the backbone story to realize a proof-of-concept (PoC) that verifies the chosen architecture. Since a working PoC can give the product owner confidence that the team is able to build such a product, that fact alone may be enough project value for the product owner. More storyotypes? You might have suspected it already, but that backbone story is just an example of another storyotype. In fact, after I started looking for an approach to capture the non-functional requirements of a project or system, I ran into a slide deck that mentioned a whole set of additional storyotypes. Dan Rawsthorne, the author, tried to define a storyotype for virtually every possible thing you might need to do in a project. Personally I think he went a bit too far, but a small set of additional storyotypes proved to be very useful anyway. Storyotype Description Compound Epic A composite user story that groups a number of stories in a logical sense. Complex Epic A user story whose content and impact must be determined later in the project, but for which it is clear that it involves a significant amount of work. Setup A story that is used to setup the project environment, including a source control environment, a project website, a build server. Technical A story that involves making a technical improvement or adjustment. Examples include introducing a coding standard, refactoring a poor design, executing a performance test. Documentation A story for writing a user manual, installation manual, etc. Training A story for developing and/or hosting a training, or having a workshop with end users. Quality Improvements A story which objective is to fix a collection of related bugs, or spent a fixed amount of time to improve the quality of the code base. Spike A story that aims to do a technical investigation to determine the usability of a specific technology, or for trying an alternative technical solution. When is the story complete? So how do you know that a user story has been successfully realized? Well, if all is good, all stories will conform with INVEST and are associated with a number of acceptance criteria (typically written down as the how-to demo) specified by the product owner. That should be enough to determine if it is functionally sound. But what you still miss is a way of explaining the stakeholders, including the product owner, when the team treats the story as finished. That may differ by team, but usually includes some or more of the following criteria. The code compiles and there are no warnings or errors. The code meets the coding standards setup by the project or the organization. The code is reviewed by a peer developer. All automated unit and integration tests have completed successfully. Visual Studio’s static code analysis tool does not report any violations. ReSharper reports no potential errors (a.k.a. everything is 'green'). The daily integration build has completed successfully. The functionality was tested by another member of the team (anybody but the developer). The feature or functionality has been signed off using the project checklist. The system functionality is tested by a tester. The visual look and feel is has been approved by an employee of the communications department. Together with the story’s how-to demo these criteria are commonly referred to as the definition-of-done. Usually, a team or project will have a default definition-of-done that applies to all stories and only mentions the particulars of that story if necessary. Then what about the planning? User stories are an excellent unit for tracking progress within your project. However, purists within the Agile community will tell you that an Agile project will have no long term plan. Instead, the functionality is realized iteratively according to the priority defined by the product owner. I agree with the latter and believe that its iterative nature is essential for dealing with the changing requirements that are common in all projects. It allows deferring decisions to the last responsible moment, and that’s always a good thing. But in reality you often can’t escape from providing at least a rough schedule to your management. How should you deal with that? What I often do to get all stakeholders to join me in a number of workshops. Using use case diagrams to illustrate the context of the discussions, I try to get enough stories on paper to represent the entire scope of the project. You need to beware though that you don’t write down too much details or have too much in-depth discussions. That would give the stakeholders a false sense of precision, and consequently, will cause them to see the stories as a formal functional design. Also, if you run into some high-level chunk of functionality for which nobody really knows what it will look like, add an epic story for it and include a spike to elaborate on the epic later on in the project. Then organize a number of shorter meetings with the team or, if the team hasn’t been formed yet, with a few experienced developers. Let them discuss every story one by one and then try to estimate the size of each story in so called story points. Some people from the Agile community say you should estimate using relative sizes only. In other words, a story that seems to require twice as much work as another story should also have twice as many story points. The story point as a unit does not have value. It’s the relative differences that are important. What works for me is that every story point corresponds to the ideal day of an experienced senior software developer. In other words, one story point means that an experienced developer familiar with the chosen architecture, technology and project methodology needs to work for 8 hours without being disturbed by telephone, email, coffee breaks, or any other distractions. Mike Cohn, author of User Stories Applied, has dedicated many chapters to this estimation technique. Ideally, each story is between 1 and 8 story points, but at the beginning of the project you still may have some epics to break up. After finishing those meetings you should have an estimate of the total size of the project. Now, in order to get from those story points to a total number of hours you need to estimate the expected productivity of the team. Mike Cohn does this by creating a table with the expected roles, their availability (to deal with part time employees), and the expected productivity compared to the ideal senior developer (as a percentage). By calculating the average productivity and multiplying it with the number of story points you’ll end up with the total number of estimated man-hours. It’s only an estimate and both the productivity can be disappointing as well as the estimate in story points may appear to be wrong. But it still gives you an initial estimate that can be used for global planning and budget discussions. Obviously it is important to ensure that you keep on continuously measuring the actual productivity. Wow, now what? By now, it should be clear that a user story is not an independent concept but something that closely resonates with many of the aspects of our work in the software industry. In this multi-part post I have tried to explain a number of those aspects and to clarify the relationship between them. But even though I’ve not touched everything as detailed as possible, I still hope I've managed to convince you about the power and potential of user stories. Last but not least, if you have any questions or comments, please do not hesitate to email me at [email protected] or tweet me at my Twitter ID ddoomen.
March 17, 2011
by Dennis Doomen
· 7,393 Views
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How to resize an ExtJS Panel, Grid, Component on Window Resize without using Ext.Viewport
This post will walk through how to resize an ExtJS Panel, Grid, Component on Window Resize without using Ext.Viewport. Problem: You have a legacy page and you want to change an html grid for an ExtJS DataGrid, because it has so many cool features. Or you have a page with some design and you are going to use only one ExtJS Component. In both cases, you also want to render your ExtJS Component to a specific DIV. Also, you want you component to be resized in case you resize the browser window. How can you do that if resize a single component in an HTML page it is not the default behavior of an ExtJS Component (except if you use Ext.Viewport)? Solution: Condor (from ExtJS Community Support Team) developed a plugin that can do that for you. I had to spend some time to understand how the plugin works, and I finally got it working as I wanted. Well, I recommend you to spend some time reading this thread: http://www.sencha.com/forum/showthread.php?28318 (if you have any issues or questions, please publish it on the thread, so other members can give you the support you need). Requirements to make the plugin work: Your have to apply the following style to the DIV (the width is up to you, the other styles are mandatory, otherwise it will not work): If you have any border around your ExtJS component, you have to set a HEIGHT. And you will also have to set a height to your ExtJS component. In this case, autoHeight will not work. If you DO NOT have any border or other design on the ExtJS component side, you do not need to set height and you can use autoHeight. In my case, I put a border on the external DIV, so I have to set Height: HTML code (all DIVs): And you need to add the plugin to the component (In this case, I’m using an ExtJS DataGrid): var grid = new Ext.grid.GridPanel({ store: store, columns: [ {header: 'Company', width: 160, sortable: true, dataIndex: 'company'}, {header: 'Price', width: 75, sortable: true, renderer: 'usMoney', dataIndex: 'price'}, {header: 'Change', width: 75, sortable: true, renderer: change, dataIndex: 'change'}, {header: '% Change', width: 75, sortable: true, renderer: pctChange, dataIndex: 'pctChange'}, {header: 'Last Updated', width: 85, sortable: true, renderer: Ext.util.Format.dateRenderer('m/d/Y'), dataIndex: 'lastChange'} ], stripeRows: true, autoExpandColumn: 'company', height: 490, autoWidth:true, title: 'Array Grid', // config options for stateful behavior stateful: true, stateId: 'grid' ,viewConfig:{forceFit:true} ,renderTo: 'reportTabContent' // render the grid to the specified div in the page ,plugins: [new Ext.ux.FitToParent("reportTabContent")] }); And done! Now you can resize the browser and the component will resize itself! I tested it on Firefox, Chrome and IE6. You can download my sample project from my GitHub: http://github.com/loiane/extjs-fit-to-parent PS.: If you want to use the full browser window, use a Viewport. Happy coding!
August 24, 2010
by Loiane Groner
· 48,790 Views
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Navigating the Five Levels of Conflict - The Agile Way
Working together day after day is an intense human experience, with all the glories and warts that emerge from constant interaction between these astonishing, disappointing, challenging, infuriating, magnificent, normal human beings we call team members. On an agile team, especially, we see this, and in our pursuit of excellence we know that conflicts arise and that we can expect both harmony and disharmony. Navigating conflict is our new mind-set, in which we help teams move from conflict to constructive disagreement as a catapult to high performance. Editor's Note: This article has been excerpted from Lyssa Adkin's book, "Coaching Agile Teams" (Addison-Wesley Signature Series (Cohn), July 2010). The Agile Coach’s Role in Conflict Coaching teams to navigate conflict may feel unfamiliar or uncomfortable to you. It did for me, even though books, articles, and studies on the subject abound. As a plan-driven project manager, I didn’t have to “go there” in the face of conflict very often because team members joined the team and left the team as we moved from phase to phase. If my feeble attempts to resolve a conflict failed, no big loss. Sooner or later, the team members in conflict would move on to other projects. With agile, however, team members stay together throughout the project. They do not move on, nor does the conflict. Given this, the agile coach faces conflict squarely, skillfully determines the severity of it, mindfully decides whether to intervene and how, generously teaches teams to navigate it, and courageously refuses to settle for a team that shrinks from greatness by avoiding it. As their coach, you help teams navigate conflict. You show them a method. You can’t give them a full-color, waterproof chart that marks the shoals and hazards. You can give them something more precious, more powerful. You can give them a guide, a framework, so that they create their own charts, whenever they need to do so. Five Levels of Conflict An agile team humming along in the rhythm of steady momentum will display conflict all the time—minor quips at one another, rolling eyeballs, heavy sighs, emotional voices, stony silences, tension in the air. You’ll witness dry wit, teasing, “just joking” comments, or just-short-of-snide remarks, all in the range of normal for an agile team. These behaviors signal normalcy for any group of people who spend considerable time together and who create a shared history. It happens in neighborhoods, community coffeehouses, churches, and agile teams—especially agile teams—where team members sit arm’s distance apart for hours on end every day while they create products together, all the while responding to the built-in pressure of the timeboxed sprint. Conflict, ever present, can be normal or destructive, and the two can be hard to tell apart. An author of many books on conflict, Speed Leas offers us agile coaches a framework we can use to determine the seriousness of the conflict (1985). This model, well suited to agile teams, looks at conflict in a deeply human and humane way. As depicted in Figure 9.1, it forms an escalation path of conflict from “Level 1: Problem to Solve” to “Level 5: World War.” (Click for larger image) Figure 9.1 Five levels of conflict Level 1: Problem to Solve We all know what conflict at level 1 feels like. Everyday frustrations and aggravations make up this level, and we experience conflicts as they rise and fall and come and go. At this level, people have different opinions, misunderstanding may have happened, conflicting goals or values may exist, and team members likely feel anxious about the conflict in the air. When in level 1, the team remains focused on determining what’s awry and how to fix it. Information flows freely, and collaboration is alive. Team members use words that are clear, specific, and factual. The language abides in the here and now, not in talking about the past. Team members check in with one another if they think a miscommunication has just happened. You will probably notice that team members seem optimistic, moving through the conflict. It’s not comfortable, but it’s not emotionally charged, either. Think of level 1 as the level of constructive disagreement that characterizes high-performing teams. Level 2: Disagreement At level 2, self-protection becomes as important as solving the problem. Team members distance themselves from one another to ensure they come out OK in the end or to establish a position for compromise they assume will come. They may talk offline with other team members to test strategies or seek advice and support. At this level, good-natured joking moves toward the half-joking barb. Nastiness gets a sugarcoating but still comes across as bitter. Yet, people aren’t hostile, just wary. Their language reflects this as their words move from the specific to the general. Fortifying their walls, they don’t share all they know about the issues. Facts play second fiddle to interpretations and create confusion about what’s really happening. Level 3: Contest At level 3, the aim is to win. A compounding effect occurs as prior conflicts and problems remain unresolved. Often, multiple issues cluster into larger issues or create a “cause.” Factions emerge in this fertile ground from which misunderstandings and power politics arise. In an agile team, this may happen subtly, because a hallmark of working agile is the feeling that we are all in this together. But it does happen. People begin to align themselves with one side or the other. Emotions become tools used to “win” supporters for one’s position. Problems and people become synonymous, opening people up to attack. As team members pay attention to building their cases, their language becomes dis-torted. They make overgeneralizations: “He always forgets to check in his code” or “You never listen to what I have to say.” They talk about the other side in presumptions: “I know what they think, but they are ignoring the real issue.” Views of themselves as benevolent and others as tarnished become magnified: “I am always the one to compromise for the good of the team” or “I have everyone’s best interest at heart” or “They are intentionally ignoring what the customer is really saying.” Discussion becomes either/or and blaming flourishes. In this combative environment, talk of peace may meet resistance. People may not be ready to move beyond blaming. Level 4: Crusade At level 4, resolving the situation isn’t good enough. Team members believe the people on the ”other side” of the issues will not change. They may believe the only option is to remove the others from the team or get removed from the team themselves. Factions become entrenched and can even solidify into a pseudo-organizational structure within the team. Identifying with a faction can overshadow identifying with the team as a whole so the team’s identity gets trounced. People and positions are seen as one, opening up people to attack for their affiliations rather than their ideas. These attacks come in the form of language rife with ideology and principles, which becomes the focus of conversation, rather than specific issues and facts. The overall attitude is righteous and punitive. Level 5: World War “Destroy!” rings out the battle cry at level 5. It’s not enough that one wins; others must lose. “We must make sure this horrible situation does not happen again!” Only one option at level 5 exists: to separate the combatants (aka team members) so that they don’t hurt one another. No constructive outcome can be had. What Should You Do About It? The goal of navigating conflict is to de-escalate. Knock it down a notch or two. As the agile coach, the first and most important question to answer is “Do I have to respond?” First, Do Nothing Agile teams—even new ones and even broken ones—can often navigate conflict by themselves, even conflict up into the level 3 range. So, sit back for a while and witness their moves. See whether they make progress. Even if it’s not perfect or the “complete” job you could do for them, if team members navigate the conflict well enough, leave them alone. To help you live with the uncomfortable feeling of watching a team’s bumbling attempts to deal with conflict, remember these words from Chris Corrigan in The Tao of Holding Space: “Everything you do for the group is one less thing they know they can do for themselves” (Corrigan 2006). The team’s bumbling is better than your perfect plan. Remember the goal of supporting the team’s self-organization (and reorganization). Your discomfort is a small price to pay. But what if you’ve decided to intervene? If you feel you have observed long enough (which should feel like a really long time) and decided to intervene, there are a few response modes you can employ: analyze and respond, use structures, and reveal. These come in order from least to most powerful for the goal of fostering self-organization. Analyze and Respond This may be the most comfortable response mode an agile coach can use because it feels familiar and at least somewhat analytical. To use analyze and respond, the agile coach considers these questions (Keip 1997): What is the level of conflict? What are the issues? How would I respond as side A? How would I respond as side B? What resolution options are open? What should I do (if anything)? When using the analyze-and-respond mode, remember that no one has the whole story. Each person’s perspective is valid and needed. If there are ten team members, you can bet there are at least ten perspectives, each of which is true in the eye of the beholder. What is your knee-jerk reaction when conflict arises? Agile coaches must be able to name that reaction and consciously choose it or reject it in service to the team. See Chapter 3, “Master Yourself,” for ways to keep yourself solidly rooted when unexpected things happen with teams. Things like conflict. Table 9.2 provides a map of successful response modes at each level. Look to this to help answer the question “What resolution options are open?” when addressing conflict in the whole-team setting (Keip 2006). Table 9.2 Conflict navigation response modes at each level When the team de-escalates, they get more options for dealing with the conflict as the tools from the next level down become available to them. The analyze-and-respond mode for navigating conflict may feel comfort-able to you—an easy shoe to slip on. If that’s the case and if it seems the best choice for your current level of skill and confidence, use it. However, you should know that it is the weakest response mode for building high-performance teams because it puts the coach in the driver’s seat. It also relies completely on analytical thinking, which is just one small way to think about conflict. So, as you feel ready, try the next two response modes.
August 18, 2010
by Lyssa Adkins
· 90,352 Views · 52 Likes
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Waterfall vs. Agile (Part 3): QA and Management
There are so many differences between Agile and Waterfall that it takes a three-part series to cover it all.
July 19, 2010
by Alberto Gutierrez
· 52,518 Views · 1 Like
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Are You A Starter, A Finisher Or An Implementer?
There are three parts to every project, starting, finishing and everything in between. Two parts of the process are very difficult to complete, starting and finishing. This is not a tutorial on project management, as much as it is a general guide for people involved in a project. For example, lots of people have ideas. Ideas are easy because they require very little risk. But, what happens after the idea? You are supposed to start the project. However, most people stop with the idea because they “don’t have time” or even “I wouldn’t know where to begin”. Kat French explains how she does her best creative work: The super-secret, hush-hush, “I could tell you, but then I’d have to kill you” secret of how I do my best creative work. Ready? It’s called “starting.” The recipe is.. there is no recipe. This isn’t science. It’s more like alchemy. There are ingredients. Usually those ingredients have certain effects. When you put them all together and apply heat…”results may vary,” Starting does not mean that everything will go well or that you will be successful. Starting just means that you took the initiative to start, and that probably puts you ahead of the majority of workers out there. In order for a project to be successful, you have to start at some point. Most people are not good starters, they need some core foundation or baseline to start with. Some people also need the structure of a formal project management methodology or a detailed task list. The term “self-starter” has been abused by the whole recruitment/HR industry to become someone who can do their own work without significant prodding. What do you call someone who can take an idea and start a project? Some people may throw the title “entrepreneur” at that person, but it also has other meanings. The key is that this person can start something. Are you that person? One problem is that the starter may not be very good at filling in the various details of the project or finishing the project. Starters may be excited by the novelty of a project, but once you get mired in details, the novelty has worn off. By the time you are trying to finish the project, the starter is probably bored or even hates his job. Given that we know that no project is ever really done, you might be able to keep the starter happy by having them begin work on the next phase of the project or a significant new feature. At the other end of the project is completion. Starters typically do not fare well as a finisher of a project. As an example, look at the typical software development project. At the beginning of the project, there is a lot of technology research and foundation or framework code that needs to be completed. Starters love that work. At the end of a project, most of the work is in validating and correcting defects, and working with other departments to ensure deployment goes smoothly. A finisher is the person that works well juggling multiple tasks, fixing defects and managing processes to completion. Obviously, this is a very different person than the starter. The finisher loves a detailed task list as it gives them a goal. If they complete all of these tasks, it is likely that the project has reached its conclusion and the application has been deployed. However, you cannot always be really finishing a project, so how do you keep the finisher happy? Similar to the starter, you can have the finisher move from one project or feature to another. They are a nice complement to the starter in terms of the tasks to be completed. Are you a finisher? But how do you have one project look like several? In project management, a large project is broken into phases, which are really just smaller projects. If you do not have a really large project, you can create smaller projects by looking for milestones in your project. Agile methodologies take this concept to the extreme by ensuring that there is a fixed time for each iteration. In some cases, an iteration could be long enough to implement one feature. So, each feature in your product could become an iteration or a small project. So, we have talked about starting and finishing, but what about the stuff in between? Someone needs to fill in the details. I started by calling this person a filler, but that does not sound like a good name for someone. So, I will call this person an implementer. This person takes the basic infrastructure and puts the application features on top of it. They create the web forms and the code to save the data, using the frameworks provided by the starter. Most people fall into this category because it has the broadest spectrum of work. Each web page or feature may look like a new project for them. They may not require a detailed task list, depending upon experience, but they look at the requirements and fill in the details. Are you an implementer? Because most projects are full of details, the implementer has plenty of work to do. They can be moved from project to project filling in the gaps that the starter and finisher do not complete. Given that there are so many details in projects, this is where a project manager will spend a bulk of their time, managing the implementers. Implementers will also be the most diverse group of people, so management of these people could be a daunting task as well. Of course, the next question from people would be who is most valuable. For that question, I give you a quote from a Seth Godin post about linchpins: A newspaper asked me the following, which practically set my hair on fire: What inherent traits would make it easier for someone to becoming a linchpin? Surely not everyone can be a linchpin? Why not? Each of these types of people are important. What good is a starter if there is nobody there to finish? If you have a finisher, who starts the project in the right direction? Once the project is started someone needs to fill in the details, and that is not the starter or the finisher. There are some of those rare people that can take a project from start to finish, and there are others that overlap into two of the three groups. But you should be honest with yourself. What are you good at? Starting? Finishing? The stuff in between? From http://regulargeek.com/2010/06/24/are-you-a-starter-a-finisher-or-an-implementer
July 5, 2010
by Robert Diana
· 18,161 Views
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Waterfall vs. Agile (Part 2): Development and Business
There are so many differences between Agile and Waterfall that it takes a three-part series to cover it all.
June 15, 2010
by Alberto Gutierrez
· 29,881 Views · 1 Like
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Writing user stories for web applications
User stories are the substitute of formal requirements documents in an agile environment: they are short summaries of a functionality that leave space to expansion and refinement when it comes the time to implement it. Writing them it's not rocket science and it is definitely something a web developer should master. Stories are not requirements, in the sense they are not required at all: the prioritization process will choose the most important stories to implement at a given time, basing on their cost and on their value. Instead of giving a list of requirements where 90% of the features are only nice to have, the customer gets to make an informed decision over which stories should be implemented first, and can handle new requirements by adding them to the global list of stories (backlog). The typical agile estimation process is not the subject of this article, but it looks like this: asking questions to the customer generates a bunch of user stories, which go into the backlog where all the ideas about functionalities are kept. Stories are estimated in relative points or ideal time, to give an idea of their size. With the customer, the developers can choose which stories to pull from the backlog into a smaller plan (iteration or release based). if new requirements come up or a user story changes too much to be considered the same, it is put in the backlog so that the next planning process can deal with it. If it's still a priority, it will be surely included in the next iteration. How to write them A major point of user stories is their focus on the value provided to the end user and not on the technical topics related to its implementation. Technical options will be chosen to satisfy the story and to estimate its cost during the subsequent planning. User stories have usually the following overly famous form: As a [role], I [feature] so that [reason] For example, As a user, I can login into the application so that the it presents me my preferences. What is a role while writing user stories? It is the analogue of the classic Uml use case diagram role: for example it can be the customer, a user of the application, an admin, developer which uses the library you're writing. The so that part is often optional, but it should described the value provided by the feature the user story describes. The feature itself can change in development but it should conserve its original value. In our example, if we make the user login with OpenID the value is conserved even if we have thrown away our own authentication mechanism. In this sense, stories do not describe describe the how, only the what, and this particular what can change is this helps to achieve the same why (a little metaphysical definition). Keep in mind that user stories have to be testable, because they are the definition of done b: you can drink champagne only when the acceptance tests for a story are passing: consider modifying your stories if it is difficult to write automated tests for them. For instance in an application which indexed files asynchronously (and it may take a lot after the user has been returned an Indexing started message) I actually addedd a dynamic page with the last additions to the index, that is updated as the last step of the pipeline of operations, to make the story more testable. Complex stories which are unclear to test are a symptom that a refinement is needed. Where to write them The general suggestion is to write every user story on a 3x5 card because this size choice keeps the stories short and to the point. Moreover, if you write on paper you can shuffle single cards around for planning pourposes. I hate to write on paper something I may edit, so when working solo, I use txt files where a story is represented by a row. I'm currently looking for a low-footprint project management tool which does not complicate my process, but I can easily move around stories from the backlog to the release or iteration plan with vim by using dd to cut a story and P or p to paste it. This is nearly as low-tech as sheets of paper. Why web applications? Web applications adapt particularly well to iterative development and to a story-based approach. Usually a web application starts with a beta that implements the most important stories to provide basic functionalities. If a story does not gather enough success online (poor response from the users), linked stories that expand it may be delayed (left in the backlog) or cancelled, to make room for other stories that have come up. There are no problems in the client side while updating the application, as all issues with upgrading are moved to the server side (such as changes to the database schema). If the developers have access to the hosting service for the application, rolling out the result of an iteration is very easy and the users may not notice it until they start to use the new features. Compare this agility with the old MS Access applications used in the offices of half of the planet. While web applications may take over the enterprise world, legacy managerial applications are widely spread and it is difficult to substitute them in one single shot. I tried with a formal waterfall approach, and failed as the requirements were too fine-grained, and impossible to prioritize: imagine a list of an hundred of queries that can be done over the database, and no idea of which are the most used. Imagine fifty different entities which represent an outdated domain model you have to replace. How do you know where to start? Even if you can implement all these requirements, how much will it cost? An agile process is our only hope for replacing this kind of applications, and if you will someday see a PHP application generating invoices in your office, it will be in part thanks to user stories.
May 25, 2010
by Giorgio Sironi
· 44,080 Views
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CollabNet Goes Agile, Acquires Danube
Today, CollabNet announced that it has acquired Danube Technologies, a company that develops Scrum project management software and conducts Scrum certification training. Founded in 2000, Danube was a small business with about 30 employees before the acquisition. Despite their small size, Danube is one of the leading Scrum training organizations in the world and they are the authors of the popular ScrumWorks software for implementing Scrum. CollabNet says they want to make ScrumWorks a part of their cloud-based developer toolset. ScrumWorks and the commercial version, ScrumWorks Pro, will continue to be sold separately from Team Forge, Collabnet's core ALM platform. In the short term, CollabNet will link the two platforms by enabling defect reports and commits tracked in TeamForge to update ScrumWorks. The backend repositories of TeamForge and ScrumWorks will remain separate and they will continue to be sold separately. CollabNet says a combined solution will be available in the second quarter of this year. ScrumWorks Pro's Enhanced Burndown Chart CollabNet will focus on making ScrumWorks available on it's cloud-based infrastructure in order to allow distributed teams to use the product. CollabNet CEO Bill Portelli believes that Scrum has become "the de facto method of managing software projects." Although many companies, including Collabnet, have branded themselves as agile, they are usually not providers of purpose-built agile tools (like Rally Software and VersionOne). Today, CollabNet can say without a doubt that they are a provider of true agile development tools (even though ScrumWorks is focused on one methodology). Before the Danube acquisition, CollabNet simply had an agile template on top of their TeamForge platform, which was not originally designed for agile processes. CollabNet was best known instead for being one of the first open source tool vendors to become profitable. The company is well known for being co-founded by Brian Behlendorf, the co-founder of Apache, and for creating the popular source control/config management tool, Subversion. With the acquisition of Danube, CollabNet could become very successful by expanding into the agile realm. Requirements management is the one area where the combined TeamForge/ScrumWorks portfolio is still lacking. The terms of the deal were not disclosed, but Danube CEO and co-founder Laszlo Szalvay says that the Danube team "couldn't be happier" with the terms. Laszlo's brother and Danube co-founder Victor Szalvay is going to become the CTO of CollabNet's new Scrum Business unit. You can see DZone's interview with Laszlo Svalvay at the Agile 2009 conference.
February 22, 2010
by Mitch Pronschinske
· 5,933 Views
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Four Methods to Automate Development Environment Setup
There are at least four methods that can be used in different combinations to make the process of setting up a complete development environment a lot less painful.
February 16, 2010
by Mitch Pronschinske
· 31,705 Views
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Agile: The New Era
It’s housecleaning time again, and like last time, I stumbled across an article I wrote back in 2006 that I don’t believe ever reached publication (at least, I don’t think it did…how am I expected to remember what I did in 2006?). For the most part, I’ve left it in its original state, except that I removed the Agile Manifesto and 12 supporting principles. There are easily enough found on the Agile Manifesto website, and the article is long enough without this duplication. The wordle at right shows the most common words used in this document. Here, in it’s otherwise unadulterated glory, is Agile: A New Era of Software Development. Agile: A New Era of Software Development Embrace Change Writing code is easy, but developing software is hard. While syntax errors are common, their severity pales in comparison to the logic flaws inherent in many software systems. The difficulty in software development is not writing code or applying a certain technology stack. Instead, the challenge lies in the specification and design of the software itself. Therein lies the essential complexity of software development, an idea introduced by Frederick Brooks in his 1987 article titled, “No Silver Bullet” [Brooks]. The most difficult aspect of software development is deciding what, exactly, needs to be built. There is certainly evidence backing this claim. The original Chaos Report shows the top three impediments to a successful development effort are lack of user input, incomplete requirements and specifications, and changing requirements and specifications [CHAOS]. No other activity, if done incorrectly, stands to compromise the system more than incorrect requirement specifications. It might not be so difficult were software a concrete entity, existing in a world where we could easily visualize it’s structure and behavior, allowing us to more reliably assess and share the impact of change. But software is a highly conceptual, invisible construct. It is considered infinitely malleable by those not intimately familiar with the conceptual complexity of it’s structure and behavior. The contractor building your home would look at you with incredulous disbelief if you suggested that the house he has 90% complete no longer met your needs, and you asked that he move walls. Or imagine how ridiculous it would sound to suggest that a new third floor be inserted to a 100 story skyscraper. Physicists labor on with firm belief that there exist an underlying set of unifying principles to serve as guidance. Or at least, there are laws of physics that we hold to be true. There are no such rules or principles that guide software development. We are left with the imagination and dreams of our clients, and they demand and deserve rapid response to change. We have made valiant attempts at conformity. Ceremonial processes attempting to define standardized activities that guide the development process have failed, however. We cannot define detailed up-front requirements specifications and expect them to survive the development lifecycle intact. We cannot establish an initial design of the conceptual construct and expect the structure to go unscathed throughout the process of construction. Software development is an error prone human activity involving experts with varying backgrounds and skills who must come together and attempt to communicate uniformly, working as a team toward a common goal. While tools and process do help, we must also accept that change is expected. We cannot treat change as evil. Instead, the tools and process used must allow us to accommodate change, treating it as an inherent part of software development. Changing requirements is a rule of our game. The software we develop must be malleable and adaptive to change, and the process we use must embrace change. We often draw comparisons between software development and various manufacturing processes. As Larman points out, however, manufacturing is a predictive process [Larman]. Herein lies one of the greatest differences between software development and the manufacturing processes to which we often draw comparisons. Manufacturing is a repeatable activity, with high rates of near-identical creation where a consistent product is produced in assembly line fashion. Little change is expected, making it possible to reliably estimate and predict the outcome. Software development is much more like new product development, where evolutionary specifications and adaptive planning is necessary to deal with the many unknowns that lie ahead. Agile Principles In early 2001, a small group of industry experts converged in Utah to discuss alternatives to heavy, document driven software development methods. Emerging from this meeting was the Agile Manifesto, a symbolic proclamation endorsing the virtues of a lighter, more flexible, people-oriented approach to software development, giving birth to the agile software development movement. (Since this is already a long article, I’ve snipped the manifesto and principles, which were included in the original version. If you’re interested, you can view the manifesto and its 12 principles on the Agile Manifesto website.) The ideas behind these 12 principles are simple, and contain no hidden messages. Of course, there are different techniques embodied within various agile processes that support these principles. The one certainty is that agile teams definitely work differently from their less agile peers. They recognize there is one end goal - to create a working, functional software product. With that in mind, they work very closely with project stakeholders throughout the development lifecycle, knowing it is the stakeholders who possess the knowledge the system must embody. Agile teams work very hard to deliver working software iteratively and incrementally, and they adopt techniques representative of that ideal. Agile project managers tend to favor intense communication and collaboration over heavy documentation. Empowering team members to make decisions enables responsiveness to change. Facilitating and negotiating requirements scope provides important feedback, helping plan future iterations, where each iteration produces a deliverable that can be shared with clients and stakeholders. Instead of forcing the team to follow a predictive project plan, agile project managers are more opportunistic. They prioritize features based on stakeholder feedback, and make adjustments as the iterations progress. Concurrent and parallel activities are favored over a phased approach. Agile project managers tend to guide the team instead of manage the team, and strongly discourage unnecessary overhead. Agile developers work with a similar set of goals, knowing functional software must be delivered early and often. They work judiciously to grow a code base built upon a solid foundation, where each day represents a step forward. They integrate frequently, and do not tolerate failed builds. A rich suite of tests provide the courage necessary to respond to change when the need arises. They avoid the notion of code ownership, empowering other developers to make improvements to any component of the software product. A common misconception is that agile processes discourage all documentation. This is untrue. Agile processes discourage unnecessary documentation, favoring collaboration as the preferred technique. Instead of using documentation to drive communication, agile processes favor face-to-face communication. Documents are encouraged by agile processes, so long as the need is immediate and significant. Transitioning to Agile Agile software development is based upon the fundamental premise that we must drive and respond to change quickly. The Agile Manifesto and 12 supporting principles serve this premise well. Advocates of agility claim speedier delivery of software, software with more business value, increased team productivity, higher quality systems, and a more enjoyable development experience. I believe each of these to hold true. Agile teams not only welcome change, they are able to respond to change at all levels of development. A project manager might discuss a changing requirement with a business client, empower a business analyst to schedule a meeting with the client to discuss further details, while a developer assesses the impact of change knowing she has the courage to accommodate the request because of the rich suite of unit tests in place. Saying you’ll be more responsive to change and creating an environment that embraces change are separate beasts, however. Practicing agility is hard work, especially if your team is accustomed to more traditional approaches. As with many things new and unfamiliar, some resistance will no doubt arise by those who aren’t fully convinced. Agile projects differ greatly from their less agile counterparts, and skeptics will have many opportunities to express their discontent. As someone experimenting with agility, you may even have doubts. But don’t be discouraged, and give your agile transition the time it deserves. One of the most significant changes you may experience is a feeling that you’ve been thrust into a chaotic nightmare. I doubt it’s unusual to feel this way. You’ve lost the security of detailed requirements specification and user sign-off. You are writing code without the comfort of knowing exactly what your stakeholders want. The detailed plans that have served as your security blanket on past projects no longer exist. And the celebrations accompanying completion of your various phase milestones are gone. Of course, these were all false comforts anyway. Stakeholders always changed their minds. Your detailed requirements and plans were outdated as quickly as they were completed. Instead, you’re now working in shorter iterations with vague requirements. Initial releases early in the lifecycle may be completely thrown away. Your first few weeks may seem wasted, with little or no valuable artifacts produced. Naysayers will immediately come forward and cite the lack of progress. Previously, those first few weeks or months were spent producing very detailed requirement specifications and beautiful design models. But don’t give up yet. In that previous world, you were only delaying risk and postponing integration, avoiding the most difficult aspect of software development until the end of the lifecycle. Now you’re attacking risk early, prioritizing features, and working hard to develop a functional piece of software as early as possible. Progress may not be at breakneck speeds, but you are learning a tremendous amount about the requirements of the system, and your velocity is sustainable. Additionally, you are also performing a number of other important lifecycle activities. Depending on the level of ceremony and bureaucracy within your organization, you will experience varying degrees of success when adopting agile techniques. As with any new technology adoption, it’s best to phase the transition. Some agile techniques are easier to adopt than others, and some serve as valuable catalysts to adopting additional techniques in the future. Don’t attempt to completely redefine how you work. It’s relatively easy to phase the agile transition, and you’ll want to adopt those principles that offer you the greatest initial reward. For instance, if you’re struggling to produce quality software at a consistent rate, implementing a continuous integration strategy will help you frequently verify the quality of your work. In addition to the comfort of knowing you have a product always in a functional state, the ability to share the product with clients using functional demos and prototypes will tighten the feedback loop and offer valuable insight to the client’s perception of the software. In a number of cases, I’ve found this to be valuable in identifying subtle requirements that can be difficult to identify in other requirements elicitation venues. Empirical Evidence In recent years, there has been a significant amount of research comparing agile development methods to their waterfall counterpart. In Agile and Iterative Development: A Manager’s Guide, Craig Larman illustrates the advantage of agile development through detailed analysis of multiple studies[Larman]. The compilation of his results are illustrated below. A study by Alan MacCormack at Harvard Business School explored whether evolutionary development techniques yielded better results than the waterfall model. The study included applications ranging from application software to embedded systems, with median values of nine developers spanning a 14 month development cycle. A key conclusion of the study, in which 75% of participants used agile techniques compared to 25% using waterfall, explained releasing software earlier, rather than later, contributed to a lower defect rate and higher productivity. There was little evidence showing that a detailed design specification resulted in a lower defect rate, however, reviews with peers did help in reducing the rate of defects. The study found that iterative and agile practices have a significant impact on defect and productivity factors, as indicated by the following points. Releasing a system with 20% of the functionality complete is associated with a decrease in the defect rate of 10 defects per month per million lines of code as compared to waiting to release a product until 40% of the functionality is complete, and an increase in productivity of eight more lines of source code per person-day. Continuous Integration, the idea of integrating and testing code as it is released to your source code repository, resulted in a decrease in the defect rate of 13 defects per month per million lines of code, and an increase in productivity of 17 lines of source code per person-day. The study also found four practices that were consistently used by the most successful development teams. The first two are deeply embedded in the ideals of agile software development. Releasing early and often to project stakeholders, using an iterative lifecycle. Continuous integration, with daily builds including regression testing. Teams with broad experience delivering multiple projects. Careful attention to modular and loosely coupled, componentized architectures. In a separate study [Shine], 88% of organizations cited improved productivity when using agile methods, and 84% cited improved productivity. 49% stated that the cost of development was less when using agile methods. Additionally, 83% claimed increased business satisfaction and 26% claimed significantly better satisfaction. Another study by Boehm and Papaccio [Boehm] discovered that a typical project experiences a 25% change in requirements, while yet another [Johnson] showed that 45% of features were never used. There have also been many research efforts devoted exclusively to the analysis of waterfall methods. Below is a summary of these findings, taken from a variety of studies. Scope management related to detailed up-front requirements was a significant contributing factor of failure [Thomas]. The U.S. Department of Defense (DoD), when following a waterfall lifecycle, experienced a 75% failure rate [Jarzombek]. This resulted in the DoD adopting a more iterative and agile approach. On a study including 400 waterfall projects, only 10% of the code was deployed. Only 20% of code deployed was used. The main factors included changing and misunderstood requirements [Cohen]. As these studies clearly illustrate, there is significant evidence showing that agile and iterative techniques offer significant advantages over the waterfall model of development. In fact, for larger projects, the statistics supporting agility were even more pronounced. Conclusion There are a variety of agile processes available to choose from, and each abide by the spirit of the manifesto and it’s 12 supporting principles. The agile movement and it’s supporters recognize that software development is a human (though not always humane) activity. Instead of forcing process on people, agile methods allow process conformance to people. Good people, working toward a common goal, can achieve great things will little ceremonial process, assuming you give them an environment that empowers them. Solid empirical evidence backs this claim. And if the quality of people is in question, it’s doubtful that any process will produce success. References [Alliance]. The Agile Alliance. Manifesto for Agile Software Development. 2001. http://www.agilemanifesto.org [Boehm]. Boehm, B, and Papaccio, P. Understanding and Controlling Software Costs. IEEE Transaction on Software Engineering. October 1988. [Brooks]. Brooks, Frederick. No Silver Bullet: Essence and Accidents of Software Engineering. 1987. [CHAOS]. The Standish Group International, Inc. The CHAOS Report. 1995. [Cohen]. Cohen, D., Larson, G., and Ware, B. Improving Software Investments through Requirements Validation. IEEE 26th Software Engineering Workshop. 2001. [Jarzombek]. Jarzombek, J. The 5th Annual JAWS S3 Proceedings. 1999. [Johnson]. Johnson, J. Keynote speech, XP 2002, Sardinia, Italy. 2002. [Larman]. Larman, Craig. Agile and Iterative Development: A Manager’s Guide. Addison-Wesley, 2004. [MacCormack]. MacCormack, A. Product-Development Practices That Work. MIT Sloan Management Review. 2001. [Shine]. Corporate Report. Agile Methodologies Survey Results. Shine Technologies Pty Ltd. Victoria, Australia. 2003. [Thomas]. Thomas, M. IT Projects Sink or Swim. British Computer Society Review. 2001. From http://techdistrict.kirkk.com
February 11, 2010
by Kirk Knoernschild
· 11,277 Views
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60 Second Agility: ROTI Meetings
Always in search of the absolute minimum of ceremony, my last team "discovered" a useful agile practice that takes 60 seconds from start to end: the ROTI Meeting.After every meeting, on the way out the door, draw a diagonal line on the whiteboard with the labels 0, 2, and 4. Each person in turn gives a number on how the meeting performed as a "Return on Time Invested" and the person with the marker draws in the rating. Here is the rating scale we used: 0 = "I'd have been better off making a Starbuck's run. Complete waste of time" 1 = "You really should have let me stay at my desk and code" 2 = "This was an OK meeting. About as valuable as if I'd been coding" 3 = "Surprisingly, this was more valuable than if I'd been writing code" 4 = "Wow, this meeting saved me tons of time. Thank goodness I didn't skip it to code" And then each person answers the same question, "What could be done to improve your number by one point?" To do this in 60 seconds means there is no discussion. The feedback is what it is; no debating, no fixing problems, and no hurt feelings. ROTI meetings create tacit, organization knowledge that can be acted upon by team members in the future. It drives a team towards less meetings (almost always a good thing), pushes team members to be more respectful of each others time and expertise, and influences meeting organizers to craft more succinct, on topic, and meaningful gatherings. It takes only 60 seconds so you might as well try it a few time! ... and now the historical details. ROTI analysis is nicely described in Esther Derby's great book "Agile Retrospectives". The practice in the context of iteration retrospectives takes more lie 5 to 10 minutes. Our team found ROTI to be so effective in retrospectives that we shortened it and held one at the end of every meeting. The actual ROTI scale is a bit more formal than what we created: 0 - Lost Principle: No Benefit Received for Time Invested Break-Even: 1 - 2- Received Benefit Equal to Time Invested High Return on Investment 3 - 4 - Received Benefit Greater than Time Invested Lastly, ROTI charts are covered in detail a few other places as well. For a mere 60 second investment, this practice is worth trying on your team. From http://hamletdarcy.blogspot.com
January 11, 2010
by Hamlet D'Arcy
· 15,722 Views
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We’re not Japanese and we don’t build cars
In 1979 a group of western dignitaries visited Japan to learn more about the manufacturing models that had been applied to great success. Konosuke Matsushita, the president of Matsushita Corporation (Panasonic, Legend, Technics etc.), opened his talk with the famous statement…. “We are going to win and the industrial west is going to lose: there’s nothing much you can do about it, because the reasons for your failure are within yourselves. Your firms are built on the Taylor model; even worse, so are your heads. For you, the essence of management is getting the ideas out of the heads of the bosses and into the hands of labour. We are beyond the Taylor model.”. This leads to two questions: What did Matsushita-san mean by this bold statement?... and why did his visitors deserve such a warm welcome?! To understand Matsushita-san’s point we need to take a brief look at the history of management science. Prior to the Industrial Revolution in the 1830’s, businesses were small-scale, intimate affairs, consisting of a limited number of individuals. To look at the management of large numbers of people prior to this point requires the study of governments and armies. During the early 1800’s technological advances led to the rise of larger industrial enterprises. Factories emerged to produce goods at a larger scale and at lower costs than traditional cottage industries. Cue the entrance of Frederick Winslow Taylor to our story. Taylor was a mechanical engineer who was fascinated with industrial efficiency. He is regarded as being one of the founding fathers of management science and wrote a book on ‘Scientific Management’1. Taylor’s industrial models separated ‘working’ from ‘doing’; he believed that it was the role of management to determine the ‘one best way’ to perform the work… “It is only through enforced standardisation of methods, enforced adoption of the best implements and working conditions and enforced cooperation that this faster work can be assured. And the duty of enforcing the adoption of standards and enforcing this cooperation rests with management alone.”. When Henry Ford set about his mission to revolutionise mass transportation in the early 1900’s, he turned to the latest management thinking to make his dream a reality. Ford created a business of such scale and effectiveness that it must have seemed to his competitors and peers analogous to turning up to the proverbial knife fight with an F-14. He progressed from building a handful of vehicles in 1909 to over 500,000 units just six years later, inventing all of the technology he needed to do it along the way. The success of Henry Ford, and later Alfred Sloan at General Motors, led to a cascade in management thinking. The Taylor model that Ford and Sloan had applied to such great success became the archetypal model for the western corporation in the 20th century. Cut to 1947… The Second World War has ended and Japanese industry has been decimated by two atomic bombs: one at Hiroshima, the other at Nagasaki. The allies, keen to support the redevelopment efforts in Japan, send over a party of management consultants to help with the work required to rebuild industry. Amongst them is William Edwards Deming, a statistician and management theorist whose philosophies had been largely ignored at home. Deming, in contrast to Taylor, believed that ‘thinking’ and ‘doing’ should not be separated, and further, employees should be encouraged and empowered to make decisions on how work should be performed. “All anyone asks for is a chance to work with pride.”. While Deming had been largely ignored in the US, the Japanese got religion. In particular organisations like Toyota and Matsushita built organisational philosophies around empowerment, teamwork and collaboration. They went from some of the worst performing businesses in the country to the strongest. By the late 1970’s world governments were looking to these emerging giants to understand what made them so successful, and in particular, so resilient. It was at this point in 1979 that Matsushita-san delivered his famous speech to western industrial leaders keen to learn the secrets of Japan’s success. It was not until 1991 that the world began to understand the power of the management systems that had been developed in Japan. A book2 was published following a study by MIT’s automotive industry research programme. The book studied the history of the automotive industry and the rise and rise of the mighty Toyota Motor Corporation; the term used to describe Toyota’s secret sauce? Lean Thinking. What Konosuke Matsushita, Toyota’s Taichi Ohno and their contemporaries understood was that the key to the success of their businesses didn’t lie in their tools, techniques, or processes, but was the result of the management philosophies that underpinned their corporations. They thought about their businesses as socio-technical systems and because of this created organisations that encouraged the right behaviours throughout. So, what does this have to do with IT? Firstly we have to recognise that IT is failing. Standish Group estimate that $85B to $145B is spent every year on failed and cancelled IT projects, and that 60% to 70% of all projects either fail outright or are considered troubled (time, cost, scope issues)3. This is a repeated pattern; we can change the country, the industry, the people and the business; the data shows a similar pattern – the problem is systemic. To solve this kind of systemic problem we need to investigate the system more closely and understand the ‘games’ that are being played out within our IT divisions. But what are the components of our IT ecosystem? When we lift the hood, there are a few areas of focus for us to investigate: people, structure, process, culture and technology. The first thing that we may notice about our corporate IT divisions is how little they differ to the Taylorised models Henry Ford and Alfred Sloan built their businesses around 100 years ago. They are structured around functional silo’s, management philosophies are command and control and empowerment is just a word that appears on corporate mouse mats. They are structured for an industrial paradigm in an information age. To make matters worse, most IT managers aspire to create self-managed teams, high levels of collaboration, innovation and continuous improvement. Many have little appreciation that the management models that they enforce, often the only ones that they know, are the very things that are preventing them from achieving the results that they dream of. So how do we change things? Firstly, it’s important to understand the differences in the two management philosophies, as the contrast is stark. For example, where Taylor’s ‘scientific management’ teaches us that managers should manage people, systems management theory teaches us that managers should manage processes. ‘Scientific management’ advocates for maximising the utilisation of our people and machinery, ‘systems management theory’ teaches us to ruthlessly eliminate waste. Although the transition is anything but easy, the results, at least so far, appear impressive. At a recent conference, Jeff Smith, CIO of Suncorp’s 2000 person IT division, estimated that they had increased throughput by over 40% whilst at the same time reducing net operating costs by over 20%4. Similarly, the BBC’s David Joyce announced in a recent article that they had reduced the time taken to engineer a software feature by over 50%5. These organisations are re-engineering many of the components of the IT taxonomy. By taking Agile software principles and introducing statistical control and scheduling techniques from Lean Thinking, teams are radically improving the efficiency and throughput of software delivery processes. They aren’t stopping here though. Product development is being refined to ensure the teams aren’t ‘building the wrong things at speeds previously thought impossible’. Planning and governance processes are being simplified to support responsiveness and adaptability in the business. Even the organisational structure itself isn’t sacred, with some of the more progressive IT divisions moving away from a top-down, hierarchical design, towards a systems based, bottom-up model, removing organisational silo’s to increase collaboration and introduce a stronger customer focus. The real change for these organisations isn’t in the structure, processes or tools of course, but in something much more subtle and complex: the way they think. Changing 100 years of western management thinking is not a simple task but industrial models just don’t cut it in an information age. Deming taught us that the processes and structures we create as leaders always produce exactly the results they are designed to produce; the system always works perfectly. In IT we have created approaches that fail (or have difficulties) 60% to 70% of the time. It’s our responsibility as leaders to change the system. This leads to the title of the article. The most common excuse I hear for avoiding change and improvement in IT leadership is that we’re not Japanese and we don’t build cars. I hear this excuse every day and it misses the point. Lean Thinking, and the management paradigm that underpins it, Systems Management Theory, focus on changing the role of leadership; it knows no national or industrial bounds, and this has been proven time again over the last 30 years, from manufacturing to healthcare. IT leadership is once again lagging behind the management curve. To re-enforce the point even further, a recent article in the Harvard Business Review6 asked some of the worlds leading academic and industrial business thinkers for the big ticket changes required in western management thinking over the next 10 years. Retraining managerial minds in systems thinking appeared in it’s top 25. Also in there was reducing the pull of the past, eliminating the pathologies of formal hierarchy and reconstructing management’s philosophical foundations. This is nothing new – management science has pointed towards collaboration, teamwork and trust for over 30 years. But mouthing the words is easy; Systems Management Theory gives us the tools to go execute. Introducing this paradigm shift, although not an easy journey, has certainly been proven achievable. Agile software development methods, based on the Toyota Production System, help us to quickly introduce Lean concepts to our software development operations. Statistical control techniques can help us improve and refine them. Recently, Lean concepts have helped scale these working-level techniques to the enterprise by borrowing philosophies, tools and techniques to solve historic problems with structure, budgeting and governance in top-down, command and control organisations. And middle management are proving willing to change, and even lead the charge, given the right leadership, support and opportunities. Driving change is hard. I often compare being a CIO to the job of a grounds keeper in a cemetery; there are a lot of people underneath you but no-one is listening. Of course, we don’t have to strive to improve the problem; I’ll leave the last word to Deming himself… “It’s not necessary to change. Survival is not mandatory.”. 1. The Principles of Scientific Management: Frederick Winslow Taylor. 2. The Machine That Changed The World: Womack, Jones, Roos. 3. Standish Chaos Reports 2000 to 2009. 4. Agile Australia (http://www.agileaustralia.com/video.html) 5. David Joyce (http://leanandkanban.wordpress.com) 6. Harvard Business Review, February 2009: Moonshots for Managers
December 23, 2009
by Richard Durnall
· 24,718 Views · 1 Like
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An Introduction to Feature-Driven Development – Part 2
This is the second part of a two-part article introducing Jeff De Luca’s Feature Driven Development (FDD) process. In particular, we are looking at how FDD differs from Scrum and eXtreme Programming-inspired approaches when it comes to working with larger teams and projects. In the first part we briefly introduced the ‘just enough’ upfront activities that FDD uses to support the additional communication that inevitably is needed in a larger project/team. In the second part of the article we cover how FDD leverages the results of those upfront activities within the highly iterative, self-managing, organized-chaos that is the delivery engine room of an FDD project. The Engine Room: Delivering Frequent, Tangible Working Results Once there is an initial overall model (FDD Process #1), an initial overall features list (FDD Process #2), and an initial overall plan (FDD Process #3) in place, an FDD project is ready to start delivering the required software feature by feature. Peter Coad, the Chief Architect on the original FDD project used the phrase ‘Deliver frequent, tangible, working results’ as a mantra to impress upon people the idea of delivering real, completed, client-valued function as often as possible. Scrum and eXtreme Programming do this using fixed length iterations of a calendar month or 2-4 weeks. FDD is different. Each Chief Programmer (lead developer) runs a series of iterations, each of which is normally a matter of a few days, and never longer than two weeks. At the start of each of these iterations, each Chief Programmer selects the next few features that make sense to implement from the backlog of feature sets (activities) that were assigned to him or her in FDD Process #2. The Chief Programmer leads the development of these features through FDD processes #4 and #5, Design by Feature (DBF) and Build By Feature (BBF). Note that iterations through the DBF/BBF processes are not fixed length, and Chief Programmers do not synchronize the start and end of their iterations with each other. In addition, the DBF/BBF processes are always executed as a pair (FDD describes them as two separate processes rather than one combined process for psychological reasons). FDD Process #4: Design By Feature After selecting the features for the iteration, a Chief Programmer needs to form their feature team. Yes, feature teams are formed and disbanded for each iteration through the DBF/BBF process pair. Using the knowledge gained from the modeling process (FDD Process #1), the Chief Programmer identifies the domain classes that are likely to be involved in this iteration, and forms his or her feature team from the owners of those classes. In practice, this means: a feature team is small, typically 3 to 5 people, because features are small. By definition, a feature team comprises of all the class owners who need to modify their classes in the development of the features during that iteration. There is no need to wait for members of other teams to change code. Therefore, there are all the benefits of code ownership and a sense of collective ownership too. Class owners may find themselves a member of multiple feature teams at the same time. This does not happen as frequently as might be supposed because iterations are so short – days not weeks. When it does, it is not a big problem in practice. Chief Programmers work together to resolve any problematic conflicts and, with care, most developers can manage the demands of occasionally belonging to more than one feature team for a short time. Once formed, the Chief Programmer facilitates the collaborative analysis and design of the features for that iteration. Depending on the complexity, this may involve the team walking through the requirements in detail with a domain expert, and studying any existing relevant documents. It also involves agreeing on the interactions and other details that need to be added to the model to support the new features. The final step in the DBF part of the iteration is to review the design. For simple features, this may be a brief sanity check of the design held within the feature team. For more significant features, the Chief Programmer will typically involve other Chief Programmers or class owners so that they are aware and can comment on the impact of the proposed design. For small team projects, the object models are frequently small enough for individual or pairs of developers to create good designs while writing tests for a particular feature or user story. For larger projects, this is not necessarily the case and designs created purely by considering the tests a feature or user story must pass are more likely to be brittle and require significant refactoring. The DBF process in FDD ensures that the overall model also guides the design, helping to maintain its ‘conceptual integrity’ [Brooks]. FDD Process #5: Build By Feature The Build by Feature (BBF) part of the iteration involves the team members coding up the features, testing them at both unit level and feature level, and holding a code inspection before promoting the completed features into the project's regular build process. Testing FDD expects developers to unit test their code. It expects feature teams to test their features. FDD is not overly concerned with how this is achieved. Projects and feature teams are free to adopt the testing tools, frameworks, and level of formality and completeness that are most appropriate. FDD does not mind if tests are written before or after code. What FDD mandates, is that the feature team deliver code that has been appropriately tested and inspected. Only once the new features have passed testing and inspection is the source code allowed into the build process. Code Inspections Most people want to know why FDD mandates code inspections, especially those that have endured sitting through hours of boring, unproductive, ego-polishing/demolishing, point-scoring sessions that formed so-called code reviews, inspections or walkthroughs. The reason FDD mandates code inspections is that research has shown time and again that when done well, inspections find more defects and different kinds of defects than testing [McConnell]. Not only that but by examining the code of the more experienced, knowledgeable developers on the team and having them explain the idioms they use, less experienced developers learn better coding techniques. In addition, knowing that their code will be inspected and not be allowed in the build unless it conforms to the agreed standards encourages developers to pay more attention to conforming to those standards. One of the benefits of working in feature teams is that the whole feature team is on the hot seat during an inspection, not just one individual. This removes much of the intensity and anxiety inherent in inspecting one individuals work. The Chief Programmer decides on the level of formality of each inspection depending on the complexity and impact of the features developed in that iteration. Where the code has little or no impact outside the feature team, an inspection will usually only involve the feature team inspecting each other’s work. Where there is significant impact the Chief Programmer pulls in other Chief Programmers and developers to both verify the code and communicate the impact of the new features. eXtreme Programming acknowledges inspections as a ‘best practice' but promotes pair programming as the logical conclusion of applying this practice. Pair programming is obviously better than individual developers delivering code without any form of inspection. However, while FDD neither mandates nor forbids pair programming, a more-traditional inspection is: fresh eyes looking at the code, catching bad assumptions made by the coder/s a Chief Programmer present to ensure the techniques passed on are good. After all, developers can just as easily teach each other bad habits as well as good habits. a change of pace for developers, a chance to step away from the keyboard and mouse for a short while. With the wide availability of automated source code formatting and static analysis tools, code inspections can now be shorter, concentrating on the logic and coding idioms involved and not getting bogged down in nit-picking such as alignment of braces, etc. The Build FDD assumes some sort of regular build process. Some teams build weekly, others daily and others continuously. FDD avoids mandating any particular build regime. This enables the project team to apply the most applicable. If a continuous integration environment makes sense, then the team is free to employ the best there is. Progress Reports Agile projects like highly visible progress information. FDD projects are no exception. In fact, because larger projects frequently have higher profiles within an organization, presenting meaningful, accurate, timely project information appropriately at the different levels of leadership/management is even more important. Conventionally, FDD projects track the development of each feature through its DBF/BBF iteration against six milestones: domain walkthrough, design, design inspection, coding, testing and inspection, and promoted to build. For each feature, Chief Programmers record the actual date a milestone is reached. Tracking each feature through these six milestones enables the project to keep an eye on how much work is 'in progress'. Too many features at a particular milestone indicate a process problem. Those promoting Kanban and other Limited Work In Progress methods have formalized this idea to strictly define what is meant by 'too many' for each of their development iteration milestones/statuses. They then refuse to move an item to a new milestone/status if the limit on the number of items at that status has been reached. This forces a team to keep items moving forward through the process [Kanban]. FDD is not so formal, leaving the Chief Programmers and Development Manager to keep an eye informally on the amount of work in progress. The Big Wallchart, Burn-Down/Up Charts, Etc For general visibility of progress within a project, the team typically lists all the features in the project complete with their owning Chief Programmer, feature team members, and the dates of each milestone achieved on a suitable wall. In addition, features can be colored to show if they are started, in-progress, completed or blocked. This allows people to stand back from the wall and get a good visual feel for the overall status of the project. They can then walk up to the wall to zoom in on particular areas and activities in more detail. Recording the date each milestone is achieved enables a team to produce burn-down or burn-up charts analogous to those produced in Scrum and XP. Chief Programmers and Project Managers can determine from these if the underlying rate of feature completion is increasing, decreasing, or stable, etc. One of the best ways to achieve this is to have the Chief Programmers regularly (typically once a week) communicate progress to either the project manager or someone dedicated to the task. That person then produces whatever roll-up and burn-down charts desired. Having an administrative person, the equivalent of the Tracker role in eXtreme Programming, perform these report formatting duties frees the Chief Programmers to spend more time on making progress rather than formatting reports about it. Parking Lot Charts For reporting to senior management, the level of individual features is often too granular. Here, FDD projects typically use a graphical report format that known as the Parking Lot chart. In a Parking Lot chart, each group of ‘parking lots’ represents one of the subject areas from the features list. Each parking lot represents one of the activities within that subject area, and displays the name of that set of features, the number of features within it, and the percentage of those features that have been completed (typically both in text and using a progress bar). The parking lots are also colored to indicate whether the features in that activity have been started, completed, or have significant blockages. The FDD parking lot format has become so popular that Mike Cohn included it in his book, Agile Planning and Estimating [Cohn]. (click for larger image) Figure 1: Example Parking Lot Chart Conclusion Feature-Driven Development combines the key advantages of other popular agile approaches with model-centric techniques and other best practices that scale to much larger teams and projects. It defines three upfront activities that provide a conceptual and management framework within which a larger-than-usual agile team can add functionality to the software, feature by feature. It is also just as applicable for smaller teams tackling non-trivial problem domains where it is worth spending just a little time to sketch a map of the journey before dashing off down the agile coding highway. Even if you and your team decide not to adopt FDD as a whole, understanding why FDD is the way it is, can provide insight into scaling traditional agile approaches beyond small, largely independent teams. Finally, I would like to say thank you to Serguei Khramtchenko and Mark Lesk at Nebulon for their corrections and suggestions incorporated in this article. References [Brooks] Frederick P. Brooks, Jr., The Mythical Man-Month, Addison Wesley [Cohn] Cohn, Agile Planning and Estimating, Prentice-Hall PTR [FDD] FDD Community Site, www.featuredrivendevelopment.com/ [Kanban] The home of Kanban software development, www.limitedwipsociety.org/ [McConnell] McConnell, Code Complete, Microsoft [Nebulon] The Latest FDD Processes available from www.nebulon.com/articles/fdd/latestprocesses.html [Palmer-1] Palmer, Felsing, A Practical Guide to Feature-Driven Development, Prentice Hall PTR
December 4, 2009
by Stephen Palmer
· 25,485 Views · 1 Like
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Data-driven tests With JUnit 4 and Excel
One nice feature in JUnit 4 is that of Parameterized Tests, which let you do data-driven testing in JUnit with a minimum of fuss. It's easy enough, and very useful, to set up basic data-driven tests by defining your test data directly in your Java class. But what if you want to get your test data from somewhere else? In this article, we look at how to obtain test data from an Excel spreadsheet. Parameterized tests allow data-driven tests in JUnit. That is, rather than having different of test cases that explore various aspects of your class's (or your application's) behavior, you define sets of input parameters and expected results, and test how your application (or, more often, one particular component) behaves. Data-driven tests are great for applications involving calculations, for testing ranges, boundary conditions and corner cases. In JUnit, a typical parameterized test might look like this: @RunWith(Parameterized.class) public class PremiumTweetsServiceTest { private int numberOfTweets; private double expectedFee; @Parameters public static Collection data() { return Arrays.asList(new Object[][] { { 0, 0.00 }, { 50, 5.00 }, { 99, 9.90 }, { 100, 10.00 }, { 101, 10.08 }, { 200, 18}, { 499, 41.92 }, { 500, 42 }, { 501, 42.05 }, { 1000, 67 }, { 10000, 517 }, }); } public PremiumTweetsServiceTest(int numberOfTweets, double expectedFee) { super(); this.numberOfTweets = numberOfTweets; this.expectedFee = expectedFee; } @Test public void shouldCalculateCorrectFee() { PremiumTweetsService premiumTweetsService = new PremiumTweetsService(); double calculatedFees = premiumTweetsService.calculateFeesDue(numberOfTweets); assertThat(calculatedFees, is(expectedFee)); } } The test class has member variables that correspond to input values (numberOfTweets) and expected results (expectedFee). The @RunWith(Parameterzed.class) annotation gets JUnit to inject your test data into instances of your test class, via the constructor. The test data is provided by a method with the @Parameters annotation. This method needs to return a collection of arrays, but beyond that you can implement it however you want. In the above example, we just create an embedded array in the Java code. However, you can also get it from other sources. To illustrate this point, I wrote a simple class that reads in an Excel spreadsheet and provides the data in it in this form: @RunWith(Parameterized.class) public class DataDrivenTestsWithSpreadsheetTest { private double a; private double b; private double aTimesB; @Parameters public static Collection spreadsheetData() throws IOException { InputStream spreadsheet = new FileInputStream("src/test/resources/aTimesB.xls"); return new SpreadsheetData(spreadsheet).getData(); } public DataDrivenTestsWithSpreadsheetTest(double a, double b, double aTimesB) { super(); this.a = a; this.b = b; this.aTimesB = aTimesB; } @Test public void shouldCalculateATimesB() { double calculatedValue = a * b; assertThat(calculatedValue, is(aTimesB)); } } The Excel spreadsheet contains multiplication tables in three columns: The SpreadsheetData class uses the Apache POI project to load data from an Excel spreadsheet and transform it into a list of Object arrays compatible with the @Parameters annotation. I've placed the source code, complete with unit-test examples on BitBucket. For the curious, the SpreadsheetData class is shown here: public class SpreadsheetData { private transient Collection data = null; public SpreadsheetData(final InputStream excelInputStream) throws IOException { this.data = loadFromSpreadsheet(excelInputStream); } public Collection getData() { return data; } private Collection loadFromSpreadsheet(final InputStream excelFile) throws IOException { HSSFWorkbook workbook = new HSSFWorkbook(excelFile); data = new ArrayList(); Sheet sheet = workbook.getSheetAt(0); int numberOfColumns = countNonEmptyColumns(sheet); List rows = new ArrayList(); List rowData = new ArrayList(); for (Row row : sheet) { if (isEmpty(row)) { break; } else { rowData.clear(); for (int column = 0; column < numberOfColumns; column++) { Cell cell = row.getCell(column); rowData.add(objectFrom(workbook, cell)); } rows.add(rowData.toArray()); } } return rows; } private boolean isEmpty(final Row row) { Cell firstCell = row.getCell(0); boolean rowIsEmpty = (firstCell == null) || (firstCell.getCellType() == Cell.CELL_TYPE_BLANK); return rowIsEmpty; } /** * Count the number of columns, using the number of non-empty cells in the * first row. */ private int countNonEmptyColumns(final Sheet sheet) { Row firstRow = sheet.getRow(0); return firstEmptyCellPosition(firstRow); } private int firstEmptyCellPosition(final Row cells) { int columnCount = 0; for (Cell cell : cells) { if (cell.getCellType() == Cell.CELL_TYPE_BLANK) { break; } columnCount++; } return columnCount; } private Object objectFrom(final HSSFWorkbook workbook, final Cell cell) { Object cellValue = null; if (cell.getCellType() == Cell.CELL_TYPE_STRING) { cellValue = cell.getRichStringCellValue().getString(); } else if (cell.getCellType() == Cell.CELL_TYPE_NUMERIC) { cellValue = getNumericCellValue(cell); } else if (cell.getCellType() == Cell.CELL_TYPE_BOOLEAN) { cellValue = cell.getBooleanCellValue(); } else if (cell.getCellType() ==Cell.CELL_TYPE_FORMULA) { cellValue = evaluateCellFormula(workbook, cell); } return cellValue; } private Object getNumericCellValue(final Cell cell) { Object cellValue; if (DateUtil.isCellDateFormatted(cell)) { cellValue = new Date(cell.getDateCellValue().getTime()); } else { cellValue = cell.getNumericCellValue(); } return cellValue; } private Object evaluateCellFormula(final HSSFWorkbook workbook, final Cell cell) { FormulaEvaluator evaluator = workbook.getCreationHelper() .createFormulaEvaluator(); CellValue cellValue = evaluator.evaluate(cell); Object result = null; if (cellValue.getCellType() == Cell.CELL_TYPE_BOOLEAN) { result = cellValue.getBooleanValue(); } else if (cellValue.getCellType() == Cell.CELL_TYPE_NUMERIC) { result = cellValue.getNumberValue(); } else if (cellValue.getCellType() == Cell.CELL_TYPE_STRING) { result = cellValue.getStringValue(); } return result; } } Data-driven testing is a great way to test calculation-based applications more thoroughly. In a real-world application, this Excel spreadsheet could be provided by the client or the end-user with the business logic encoded within the spreadsheet. (The POI library handles numerical calculations just fine, though it seems to have a bit of trouble with calculations using dates). In this scenario, the Excel spreadsheet becomes part of your acceptance tests, and helps to define your requirements, allows effective test-driven development of the code itself, and also acts as part of your acceptance tests. From http://weblogs.java.net/blog/johnsmart
November 30, 2009
by John Ferguson Smart
· 43,446 Views · 1 Like
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An Introduction to Feature-Driven Development
Feature-Driven Development (FDD) is one of the agile processes not talked or written about very much. Often mentioned in passing in agile software development books and forums, few actually know much about it. However, if you need to apply agile to larger projects and teams, it is worthwhile taking the time to understand FDD a little more The natural habitat of Scrum and XP-inspired approaches is a small team of skilled and disciplined developers. It remains a significant challenge to scale these approaches to larger projects and larger teams. Some have been successful but many have struggled. Feature-Driven Development (FDD) invented by Jeff De Luca is different. While just as applicable for small teams, Jeff designed FDD from the ground up to work for a larger team. Larger teams present different challenges. For example, a small team of disciplined and highly skilled developers by definition is likely to succeed regardless of which agile method they use. In contrast, it is unrealistic to expect that everyone in a larger team is equally skilled and disciplined. For this and other reasons, FDD makes different choices to Scrum and XP in a number of areas. In the first part of this two-part article, we briefly introduce the ‘just enough’ upfront activities that FDD uses to support the additional communication that inevitably is needed in a larger project/team. In the second part of the article, we cover how the highly iterative delivery part of FDD differs from Scrum and XP-inspired approaches. Iteration Zero:Getting Set to Deliver Most experienced agile teams are familiar with the concept of an iteration zero, a relatively short period for a team to put in place what they need to start delivering client-valued functionality in subsequent iterations. Despite general acceptance within the agile community that some form of iteration zero is a pragmatic necessity on most projects, neither Scrum nor eXtreme Programming formally have much to say about it. In contrast, an FDD project is organized around five 'processes', of which the first three can be considered roughly the equivalent of iteration zero activities. FDD does not use the term, iteration zero. It calls these three ‘processes’ initial project-wide activities. Each of the FDD processes is described so that it can be printed, in a typical-sized font, on no more than two sides of letter-sized paper. The most recent versions of the FDD processes are available from the FDD section of the Nebulon website, but very briefly an FDD project: … starts with the creation of a domain object model in collaboration with Domain Experts. Usinginformation from the modeling activity, and from any other requirements activities that have taken place, the developers go onto create a features list. Then a rough plan is drawn up and responsibilities assigned. Now we are ready to repeatedly take small groups of features through a design and build iteration that lasts no longer than two weeks and is often much shorter, sometimes only a matter of hours...[Palmer-1] FDD Process #1: Develop an Overall Model For many who have escaped from the perils of large, upfront analysis and design phases to the freedom and discipline of Scrum and eXtreme Programming-inspired approaches, the idea of developing a domain object model at the start of a project is controversial. In FDD, however, the building of an object model is not a long, drawn-out, activity performed by an elite few using expensive CASE tools. The modelers do not format the resulting model into a large document and throw it over the wall for developers to implement. Instead, building an initial object model in FDD is an intense, highly iterative, collaborative and generally enjoyable activity involving ‘domain and development members under the guidance of an experienced object modeler in the role of Chief Architect' [Nebulon]. FDD Process #1 describes the tasks and quality checks for executing this work, and while not mandatory, the object model is typically built using Peter Coad's modeling in color technique (modeling in color needs an introductory article all of its own [Palmer-2]). The idea is for both domain and development members of the team to gain a good, shared understanding of the problem domain. It is important that everyone understands the key problem domain concepts, relationships, and interactions. In doing so, the team as a whole learn to communicate with each other and start to establish a shared vocabulary, what Eric Evans calls a Ubiquitous Language [Evans]. The object model developed at this point concentrates on breadth rather than depth; depth is added iteratively through the lifetime of the project. The model is, therefore, a living artifact. Throughout the project, the model becomes the primary vehicle around which the team discusses, challenges, and clarifies requirements. FDD Process #2: Build a Features List With the first activity being to build an object model, some may conclude FDD is a model-driven process. It is not. While the model is central to the process, an FDD project is like a Scrum or eXtreme Programming project in being requirement-driven. Small, client-valued requirements referred to as features drive the project; the model merely helps guide. Formally, FDD defines a feature as a small, client-valued function expressed in the form:
November 20, 2009
by Stephen Palmer
· 108,982 Views · 6 Likes
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War Fighter on the NetBeans Platform
Agile Client is a NetBeans Platform application developed by Northrop Grumman in partnership with the Defense Information System Agency (DISA). It brings the war fighter a 3-D common operational picture (COP) workstation designed for greater efficiency and mission effectiveness. This efficiency is empowered by its ability to be installed and upgraded on demand. Its mission effectiveness is permitted by the ability to tailor the user’s application with only the capabilities and data they need for their specific mission. The interview below is with Charlie Black, who runs the team using the NetBeans Platform at Northrop Grumman. Hi Charlie, who are you and what do you do? My name is Charlie Black and I have worked for Northrop Grumman since 1998. Over that time I have been working as a software engineer on a Global Command and Control System (GCCS) program supporting data fusion, dissemination and display technologies. I am currently running a team that uses the NetBeans Platform for a product called Agile Client, which is now part of GCCS. Team: Greg Gibsen, Charlie Black, Brice Bingman and James Maloney What are the technical specifics of Agile Client? The Agile Client uses several commercial off the shelf (COTS) products that make up its core feature set: It uses the NetBeans Platform, which provides the services common to almost all large desktop applications: window management, menus, settings and storage, an update manager, and file access. For map and visual rendering, Agile Client uses NASA’s World Wind product, enabling the retrieval of geospatial data via open standards that are embraced by the international community. For providing data services, Agile Client uses Gemstone GemFire, which provides ultra low-latency distributed caching with high availability and no data loss. Here's a screenshot of Agile Client in action: Agile Client is also integrated with GCCS COP Collaboration. This allows one or more war fighters to work simultaneously on a single map. They can collaboratively create GCCS Overlays, share files and communicate by instant messaging and Voice over IP. This is all done with the Extensible Messaging and Presence Protocol (XMPP), which is a set of open XML technologies for presence and real-time communication. What are the two or three things that you are happiest about, relating to this application? Since the NetBeans Platform is based on standard Java UI technologies, we are able to integrate existing Java windows directly, without any issues. This has accelerated our development substantially. Using Sun UI guidelines and reusable components in any new development, we have actually made an application that is embraced by our customers as looking modern. Underneath this application is the NetBeans Platform. Why? The main reason for going with a rich client platform such as the NetBeans Platform was the module system. It will help with our deployment of a large scale application on an enterprise level. I can envision a future where there will be hundreds of modules deployed in the application. Then, using the update center, we can keep those applications up to date. How did you find out about it? When? Why did you start using it? We have known about NetBeans for a long time. However it was used mainly as a developer tool. It wasn’t until NetBeans 6.0 that we started using it as our platform for basing new work on. What are the main things you gained from the NetBeans Platform? Using the NetBeans Platform, we decreased our time to develop our application by using existing window components. Also, the automatic updates are integral to our final application. In the past, it would have taken months or even years to get a patch to our end users. That said, the most significant gain has been the community! Which APIs have you used? Which ones are your favorites and why? We actually use several API sets, with just about every one enabled. The Windows API is incredible, as that is what the end user sees that allows them to tailor their display. With the customization of toolbars, the end-user can make their own ad-hoc workflow. The other API that we have been impressed with is the Nodes API, providing a view to our layers on the 3D globe. What could be improved about the NetBeans Platform? In our community OSGi is a big item, so if NetBeans could formally handle them for module deployment that would be a monumental win. Imagine a module of business intelligence that can be deployed in Glassfish and in the NetBeans Platform. I realize that some work has already been done in this area, but to see it on an official roadmap would be remarkable. After that, the Properties window could use something to make it more appealing. We are thinking of dropping our own Properties window in favor of the NetBeans implementation. Overall, we have been really happy with the NetBeans Platform and the features it provides. Do you have some tips and tricks for a complete newbie, who is getting started with the NetBeans Platform? When new team members join, I customarily distribute to them a book on the NetBeans Platform. For further aid, I point them to the NetBeans Developer Wiki. There is an amazing amount of information available, detailing not only what the NetBeans Platform can do for you, but what can you do with the NetBeans Platform as well. If more assistance is needed, I recommend just asking the community. Someone can usually help in answering any level of questions. How have customers responded to this application and what are your plans for its future? Our customers are very pleased with the application and they are moving forward with plans to base future work on the Agile Client. Internally, we have made Agile Client with the goal of releasing portions back to the community. However, before that can be done, we have to figure out what that means from our customer’s standpoint.
March 31, 2009
by Geertjan Wielenga
· 37,559 Views
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