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.

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.

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.

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.

There are so many differences between Agile and Waterfall that it takes a three-part series to cover it all.

There are so many differences between Agile and Waterfall that it takes a three-part series to cover it all.

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.

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

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

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: