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  • More Animation - Self Dismissing Dialogs

    - by Duncan Mills
    In my earlier articles on animation, I discussed various slide, grow and  flip transitions for items and containers.  In this article I want to discuss a fade animation and specifically the use of fades and auto-dismissal for informational dialogs.  If you use a Mac, you may be familiar with Growl as a notification system, and the nice way that messages that are informational just fade out after a few seconds. So in this blog entry I wanted to discuss how we could make an ADF popup behave in the same way. This can be an effective way of communicating information to the user without "getting in the way" with modal alerts. This of course, has been done before, but everything I've seen previously requires something like JQuery to be in the mix when we don't really need it to be.  The solution I've put together is nice and generic and will work with either <af:panelWindow> or <af:dialog> as a the child of the popup. In terms of usage it's pretty simple to use we  just need to ensure that the popup itself has clientComponent is set to true and includes the animation JavaScript (animateFadingPopup) on a popupOpened event: <af:popup id="pop1" clientComponent="true">   <af:panelWindow title="A Fading Message...">    ...  </af:panelWindow>   <af:clientListener method="animateFadingPopup" type="popupOpened"/> </af:popup>   The popup can be invoked in the normal way using showPopupBehavior or JavaScript, no special code is required there. As a further twist you can include an additional clientAttribute called preFadeDelay to define a delay before the fade itself starts (the default is 5 seconds) . To set the delay to just 2 seconds for example: <af:popup ...>   ...   <af:clientAttribute name="preFadeDelay" value="2"/>   <af:clientListener method="animateFadingPopup" type="popupOpened"/>  </af:popup> The Animation Styles  As before, we have a couple of CSS Styles which define the animation, I've put these into the skin in my case, and, as in the other articles, I've only defined the transitions for WebKit browsers (Chrome, Safari) at the moment. In this case, the fade is timed at 5 seconds in duration. .popupFadeReset {   opacity: 1; } .popupFadeAnimate {   opacity: 0;   -webkit-transition: opacity 5s ease-in-out; } As you can see here, we are achieving the fade by simply setting the CSS opacity property. The JavaScript The final part of the puzzle is, of course, the JavaScript, there are four functions, these are generic (apart from the Style names which, if you've changed above, you'll need to reflect here): The initial function invoked from the popupOpened event,  animateFadingPopup which starts a timer and provides the initial delay before we start to fade the popup. The function that applies the fade animation to the popup - initiatePopupFade. The callback function - closeFadedPopup used to reset the style class and correctly hide the popup so that it can be invoked again and again.   A utility function - findFadeContainer, which is responsible for locating the correct child component of the popup to actually apply the style to. Function - animateFadingPopup This function, as stated is the one hooked up to the popupOpened event via a clientListener. Because of when the code is called it does not actually matter how you launch the popup, or if the popup is re-used from multiple places. All usages will get the fade behavior. /**  * Client listener which will kick off the animation to fade the dialog and register  * a callback to correctly reset the popup once the animation is complete  * @param event  */ function animateFadingPopup(event) { var fadePopup = event.getSource();   var fadeCandidate = false;   //Ensure that the popup is initially Opaque   //This handles the situation where the user has dismissed   //the popup whilst it was in the process of fading   var fadeContainer = findFadeContainer(fadePopup);   if (fadeContainer != null) {     fadeCandidate = true;     fadeContainer.setStyleClass("popupFadeReset");   }   //Only continue if we can actually fade this popup   if (fadeCandidate) {   //See if a delay has been specified     var waitTimeSeconds = event.getSource().getProperty('preFadeDelay');     //Default to 5 seconds if not supplied     if (waitTimeSeconds == undefined) {     waitTimeSeconds = 5;     }     // Now call the fade after the specified time     var fadeFunction = function () {     initiatePopupFade(fadePopup);     };     var fadeDelayTimer = setTimeout(fadeFunction, (waitTimeSeconds * 1000));   } } The things to note about this function is the initial check that we have to do to ensure that the container is currently visible and reset it's style to ensure that it is.  This is to handle the situation where the popup has begun the fade, and yet the user has still explicitly dismissed the popup before it's complete and in doing so has prevented the callback function (described later) from executing. In this particular situation the initial display of the dialog will be (apparently) missing it's normal animation but at least it becomes visible to the user (and most users will probably not notice this difference in any case). You'll notice that the style that we apply to reset the  opacity - popupFadeReset, is not applied to the popup component itself but rather the dialog or panelWindow within it. More about that in the description of the next function findFadeContainer(). Finally, assuming that we have a suitable candidate for fading, a JavaScript  timer is started using the specified preFadeDelay wait time (or 5 seconds if that was not supplied). When this timer expires then the main animation styleclass will be applied using the initiatePopupFade() function Function - findFadeContainer As a component, the <af:popup> does not support styleClass attribute, so we can't apply the animation style directly.  Instead we have to look for the container within the popup which defines the window object that can have a style attached.  This is achieved by the following code: /**  * The thing we actually fade will be the only child  * of the popup assuming that this is a dialog or window  * @param popup  * @return the component, or null if this is not valid for fading  */ function findFadeContainer(popup) { var children = popup.getDescendantComponents();   var fadeContainer = children[0];   if (fadeContainer != undefined) {   var compType = fadeContainer.getComponentType();     if (compType == "oracle.adf.RichPanelWindow" || compType == "oracle.adf.RichDialog") {     return fadeContainer;     }   }   return null; }  So what we do here is to grab the first child component of the popup and check its type. Here I decided to limit the fade behaviour to only <af:dialog> and <af:panelWindow>. This was deliberate.  If  we apply the fade to say an <af:noteWindow> you would see the text inside the balloon fade, but the balloon itself would hang around until the fade animation was over and then hide.  It would of course be possible to make the code smarter to walk up the DOM tree to find the correct <div> to apply the style to in order to hide the whole balloon, however, that means that this JavaScript would then need to have knowledge of the generated DOM structure, something which may change from release to release, and certainly something to avoid. So, all in all, I think that this is an OK restriction and frankly it's windows and dialogs that I wanted to fade anyway, not balloons and menus. You could of course extend this technique and handle the other types should you really want to. One thing to note here is the selection of the first (children[0]) child of the popup. It does not matter if there are non-visible children such as clientListener before the <af:dialog> or <af:panelWindow> within the popup, they are not included in this array, so picking the first element in this way seems to be fine, no matter what the underlying ordering is within the JSF source.  If you wanted a super-robust version of the code you might want to iterate through the children array of the popup to check for the right type, again it's up to you.  Function -  initiatePopupFade  On to the actual fading. This is actually very simple and at it's heart, just the application of the popupFadeAnimate style to the correct component and then registering a callback to execute once the fade is done. /**  * Function which will kick off the animation to fade the dialog and register  * a callback to correctly reset the popup once the animation is complete  * @param popup the popup we are animating  */ function initiatePopupFade(popup) { //Only continue if the popup has not already been dismissed    if (popup.isPopupVisible()) {   //The skin styles that define the animation      var fadeoutAnimationStyle = "popupFadeAnimate";     var fadeAnimationResetStyle = "popupFadeReset";     var fadeContainer = findFadeContainer(popup);     if (fadeContainer != null) {     var fadeContainerReal = AdfAgent.AGENT.getElementById(fadeContainer.getClientId());       //Define the callback this will correctly reset the popup once it's disappeared       var fadeCallbackFunction = function (event) {       closeFadedPopup(popup, fadeContainer, fadeAnimationResetStyle);         event.target.removeEventListener("webkitTransitionEnd", fadeCallbackFunction);       };       //Initiate the fade       fadeContainer.setStyleClass(fadeoutAnimationStyle);       //Register the callback to execute once fade is done       fadeContainerReal.addEventListener("webkitTransitionEnd", fadeCallbackFunction, false);     }   } } I've added some extra checks here though. First of all we only start the whole process if the popup is still visible. It may be that the user has closed the popup before the delay timer has finished so there is no need to start animating in that case. Again we use the findFadeContainer() function to locate the correct component to apply the style to, and additionally we grab the DOM id that represents that container.  This physical ID is required for the registration of the callback function. The closeFadedPopup() call is then registered on the callback so as to correctly close the now transparent (but still there) popup. Function -  closeFadedPopup The final function just cleans things up: /**  * Callback function to correctly cancel and reset the style in the popup  * @param popup id of the popup so we can close it properly  * @param contatiner the window / dialog within the popup to actually style  * @param resetStyle the syle that sets the opacity back to solid  */ function closeFadedPopup(popup, container, resetStyle) { container.setStyleClass(resetStyle);   popup.cancel(); }  First of all we reset the style to make the popup contents opaque again and then we cancel the popup.  This will ensure that any of your user code that is waiting for a popup cancelled event will actually get the event, additionally if you have done this as a modal window / dialog it will ensure that the glasspane is dismissed and you can interact with the UI again.  What's Next? There are several ways in which this technique could be used, I've been working on a popup here, but you could apply the same approach to in-line messages. As this code (in the popup case) is generic it will make s pretty nice declarative component and maybe, if I get time, I'll look at constructing a formal Growl component using a combination of this technique, and active data push. Also, I'm sure the above code can be improved a little too.  Specifically things like registering a popup cancelled listener to handle the style reset so that we don't loose the subtle animation that takes place when the popup is opened in that situation where the user has closed the in-fade dialog.

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  • Inside the Concurrent Collections: ConcurrentDictionary

    - by Simon Cooper
    Using locks to implement a thread-safe collection is rather like using a sledgehammer - unsubtle, easy to understand, and tends to make any other tool redundant. Unlike the previous two collections I looked at, ConcurrentStack and ConcurrentQueue, ConcurrentDictionary uses locks quite heavily. However, it is careful to wield locks only where necessary to ensure that concurrency is maximised. This will, by necessity, be a higher-level look than my other posts in this series, as there is quite a lot of code and logic in ConcurrentDictionary. Therefore, I do recommend that you have ConcurrentDictionary open in a decompiler to have a look at all the details that I skip over. The problem with locks There's several things to bear in mind when using locks, as encapsulated by the lock keyword in C# and the System.Threading.Monitor class in .NET (if you're unsure as to what lock does in C#, I briefly covered it in my first post in the series): Locks block threads The most obvious problem is that threads waiting on a lock can't do any work at all. No preparatory work, no 'optimistic' work like in ConcurrentQueue and ConcurrentStack, nothing. It sits there, waiting to be unblocked. This is bad if you're trying to maximise concurrency. Locks are slow Whereas most of the methods on the Interlocked class can be compiled down to a single CPU instruction, ensuring atomicity at the hardware level, taking out a lock requires some heavy lifting by the CLR and the operating system. There's quite a bit of work required to take out a lock, block other threads, and wake them up again. If locks are used heavily, this impacts performance. Deadlocks When using locks there's always the possibility of a deadlock - two threads, each holding a lock, each trying to aquire the other's lock. Fortunately, this can be avoided with careful programming and structured lock-taking, as we'll see. So, it's important to minimise where locks are used to maximise the concurrency and performance of the collection. Implementation As you might expect, ConcurrentDictionary is similar in basic implementation to the non-concurrent Dictionary, which I studied in a previous post. I'll be using some concepts introduced there, so I recommend you have a quick read of it. So, if you were implementing a thread-safe dictionary, what would you do? The naive implementation is to simply have a single lock around all methods accessing the dictionary. This would work, but doesn't allow much concurrency. Fortunately, the bucketing used by Dictionary allows a simple but effective improvement to this - one lock per bucket. This allows different threads modifying different buckets to do so in parallel. Any thread making changes to the contents of a bucket takes the lock for that bucket, ensuring those changes are thread-safe. The method that maps each bucket to a lock is the GetBucketAndLockNo method: private void GetBucketAndLockNo( int hashcode, out int bucketNo, out int lockNo, int bucketCount) { // the bucket number is the hashcode (without the initial sign bit) // modulo the number of buckets bucketNo = (hashcode & 0x7fffffff) % bucketCount; // and the lock number is the bucket number modulo the number of locks lockNo = bucketNo % m_locks.Length; } However, this does require some changes to how the buckets are implemented. The 'implicit' linked list within a single backing array used by the non-concurrent Dictionary adds a dependency between separate buckets, as every bucket uses the same backing array. Instead, ConcurrentDictionary uses a strict linked list on each bucket: This ensures that each bucket is entirely separate from all other buckets; adding or removing an item from a bucket is independent to any changes to other buckets. Modifying the dictionary All the operations on the dictionary follow the same basic pattern: void AlterBucket(TKey key, ...) { int bucketNo, lockNo; 1: GetBucketAndLockNo( key.GetHashCode(), out bucketNo, out lockNo, m_buckets.Length); 2: lock (m_locks[lockNo]) { 3: Node headNode = m_buckets[bucketNo]; 4: Mutate the node linked list as appropriate } } For example, when adding another entry to the dictionary, you would iterate through the linked list to check whether the key exists already, and add the new entry as the head node. When removing items, you would find the entry to remove (if it exists), and remove the node from the linked list. Adding, updating, and removing items all follow this pattern. Performance issues There is a problem we have to address at this point. If the number of buckets in the dictionary is fixed in the constructor, then the performance will degrade from O(1) to O(n) when a large number of items are added to the dictionary. As more and more items get added to the linked lists in each bucket, the lookup operations will spend most of their time traversing a linear linked list. To fix this, the buckets array has to be resized once the number of items in each bucket has gone over a certain limit. (In ConcurrentDictionary this limit is when the size of the largest bucket is greater than the number of buckets for each lock. This check is done at the end of the TryAddInternal method.) Resizing the bucket array and re-hashing everything affects every bucket in the collection. Therefore, this operation needs to take out every lock in the collection. Taking out mutiple locks at once inevitably summons the spectre of the deadlock; two threads each hold a lock, and each trying to acquire the other lock. How can we eliminate this? Simple - ensure that threads never try to 'swap' locks in this fashion. When taking out multiple locks, always take them out in the same order, and always take out all the locks you need before starting to release them. In ConcurrentDictionary, this is controlled by the AcquireLocks, AcquireAllLocks and ReleaseLocks methods. Locks are always taken out and released in the order they are in the m_locks array, and locks are all released right at the end of the method in a finally block. At this point, it's worth pointing out that the locks array is never re-assigned, even when the buckets array is increased in size. The number of locks is fixed in the constructor by the concurrencyLevel parameter. This simplifies programming the locks; you don't have to check if the locks array has changed or been re-assigned before taking out a lock object. And you can be sure that when a thread takes out a lock, another thread isn't going to re-assign the lock array. This would create a new series of lock objects, thus allowing another thread to ignore the existing locks (and any threads controlling them), breaking thread-safety. Consequences of growing the array Just because we're using locks doesn't mean that race conditions aren't a problem. We can see this by looking at the GrowTable method. The operation of this method can be boiled down to: private void GrowTable(Node[] buckets) { try { 1: Acquire first lock in the locks array // this causes any other thread trying to take out // all the locks to block because the first lock in the array // is always the one taken out first // check if another thread has already resized the buckets array // while we were waiting to acquire the first lock 2: if (buckets != m_buckets) return; 3: Calculate the new size of the backing array 4: Node[] array = new array[size]; 5: Acquire all the remaining locks 6: Re-hash the contents of the existing buckets into array 7: m_buckets = array; } finally { 8: Release all locks } } As you can see, there's already a check for a race condition at step 2, for the case when the GrowTable method is called twice in quick succession on two separate threads. One will successfully resize the buckets array (blocking the second in the meantime), when the second thread is unblocked it'll see that the array has already been resized & exit without doing anything. There is another case we need to consider; looking back at the AlterBucket method above, consider the following situation: Thread 1 calls AlterBucket; step 1 is executed to get the bucket and lock numbers. Thread 2 calls GrowTable and executes steps 1-5; thread 1 is blocked when it tries to take out the lock in step 2. Thread 2 re-hashes everything, re-assigns the buckets array, and releases all the locks (steps 6-8). Thread 1 is unblocked and continues executing, but the calculated bucket and lock numbers are no longer valid. Between calculating the correct bucket and lock number and taking out the lock, another thread has changed where everything is. Not exactly thread-safe. Well, a similar problem was solved in ConcurrentStack and ConcurrentQueue by storing a local copy of the state, doing the necessary calculations, then checking if that state is still valid. We can use a similar idea here: void AlterBucket(TKey key, ...) { while (true) { Node[] buckets = m_buckets; int bucketNo, lockNo; GetBucketAndLockNo( key.GetHashCode(), out bucketNo, out lockNo, buckets.Length); lock (m_locks[lockNo]) { // if the state has changed, go back to the start if (buckets != m_buckets) continue; Node headNode = m_buckets[bucketNo]; Mutate the node linked list as appropriate } break; } } TryGetValue and GetEnumerator And so, finally, we get onto TryGetValue and GetEnumerator. I've left these to the end because, well, they don't actually use any locks. How can this be? Whenever you change a bucket, you need to take out the corresponding lock, yes? Indeed you do. However, it is important to note that TryGetValue and GetEnumerator don't actually change anything. Just as immutable objects are, by definition, thread-safe, read-only operations don't need to take out a lock because they don't change anything. All lockless methods can happily iterate through the buckets and linked lists without worrying about locking anything. However, this does put restrictions on how the other methods operate. Because there could be another thread in the middle of reading the dictionary at any time (even if a lock is taken out), the dictionary has to be in a valid state at all times. Every change to state has to be made visible to other threads in a single atomic operation (all relevant variables are marked volatile to help with this). This restriction ensures that whatever the reading threads are doing, they never read the dictionary in an invalid state (eg items that should be in the collection temporarily removed from the linked list, or reading a node that has had it's key & value removed before the node itself has been removed from the linked list). Fortunately, all the operations needed to change the dictionary can be done in that way. Bucket resizes are made visible when the new array is assigned back to the m_buckets variable. Any additions or modifications to a node are done by creating a new node, then splicing it into the existing list using a single variable assignment. Node removals are simply done by re-assigning the node's m_next pointer. Because the dictionary can be changed by another thread during execution of the lockless methods, the GetEnumerator method is liable to return dirty reads - changes made to the dictionary after GetEnumerator was called, but before the enumeration got to that point in the dictionary. It's worth listing at this point which methods are lockless, and which take out all the locks in the dictionary to ensure they get a consistent view of the dictionary: Lockless: TryGetValue GetEnumerator The indexer getter ContainsKey Takes out every lock (lockfull?): Count IsEmpty Keys Values CopyTo ToArray Concurrent principles That covers the overall implementation of ConcurrentDictionary. I haven't even begun to scratch the surface of this sophisticated collection. That I leave to you. However, we've looked at enough to be able to extract some useful principles for concurrent programming: Partitioning When using locks, the work is partitioned into independant chunks, each with its own lock. Each partition can then be modified concurrently to other partitions. Ordered lock-taking When a method does need to control the entire collection, locks are taken and released in a fixed order to prevent deadlocks. Lockless reads Read operations that don't care about dirty reads don't take out any lock; the rest of the collection is implemented so that any reading thread always has a consistent view of the collection. That leads us to the final collection in this little series - ConcurrentBag. Lacking a non-concurrent analogy, it is quite different to any other collection in the class libraries. Prepare your thinking hats!

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  • Laissez les bon temps rouler! (Microsoft BI Conference 2010)

    - by smisner
    Laissez les bons temps rouler" is a Cajun phrase that I heard frequently when I lived in New Orleans in the mid-1990s. It means "Let the good times roll!" and encapsulates a feeling of happy expectation. As I met with many of my peers and new acquaintances at the Microsoft BI Conference last week, this phrase kept running through my mind as people spoke about their plans in their respective businesses, the benefits and opportunities that the recent releases in the BI stack are providing, and their expectations about the future of the BI stack.Notwithstanding some jabs here and there to point out the platform is neither perfect now nor will be anytime soon (along with admissions that the competitors are also not perfect), and notwithstanding several missteps by the event organizers (which I don't care to enumerate), the overarching mood at the conference was positive. It was a refreshing change from the doom and gloom hovering over several conferences that I attended in 2009. Although many people expect economic hardships to continue over the coming year or so, everyone I know in the BI field is busier than ever and expects to stay busy for quite a while.Self-Service BISelf-service was definitely a theme of the BI conference. In the keynote, Ted Kummert opened with a look back to a fairy tale vision of self-service BI that he told in 2008. At that time, the fairy tale future was a time when "every end user was able to use BI technologies within their job in order to move forward more effectively" and transitioned to the present time in which SQL Server 2008 R2, Office 2010, and SharePoint 2010 are available to deliver managed self-service BI.This set of technologies is presumably poised to address the needs of the 80% of users that Kummert said do not use BI today. He proceeded to outline a series of activities that users ought to be able to do themselves--from simple changes to a report like formatting or an addtional data visualization to integration of an additional data source. The keynote then continued with a series of demonstrations of both current and future technology in support of self-service BI. Some highlights that interested me:PowerPivot, of course, is the flagship product for self-service BI in the Microsoft BI stack. In the TechEd keynote, which was open to the BI conference attendees, Amir Netz (twitter) impressed the audience by demonstrating interactivity with a workbook containing 100 million rows. He upped the ante at the BI keynote with his demonstration of a future-state PowerPivot workbook containing over 2 billion records. It's important to note that this volume of data is being processed by a server engine, and not in the PowerPivot client engine. (Yes, I think it's impressive, but none of my clients are typically wrangling with 2 billion records at a time. Maybe they're thinking too small. This ability to work quickly with large data sets has greater implications for BI solutions than for self-service BI, in my opinion.)Amir also demonstrated KPIs for the future PowerPivot, which appeared to be easier to implement than in any other Microsoft product that supports KPIs, apart from simple KPIs in SharePoint. (My initial reaction is that we have one more place to build KPIs. Great. It's confusing enough. I haven't seen how well those KPIs integrate with other BI tools, which will be important for adoption.)One more PowerPivot feature that Amir showed was a graphical display of the lineage for calculations. (This is hugely practical, especially if you build up calculations incrementally. You can more easily follow the logic from calculation to calculation. Furthermore, if you need to make a change to one calculation, you can assess the impact on other calculations.)Another product demonstration will be available within the next 30 days--Pivot for Reporting Services. If you haven't seen this technology yet, check it out at www.getpivot.com. (It definitely has a wow factor, but I'm skeptical about its practicality. However, I'm looking forward to trying it out with data that I understand.)Michael Tejedor (twitter) demonstrated a feature that I think is really interesting and not emphasized nearly enough--overshadowed by PowerPivot, no doubt. That feature is the Microsoft Business Intelligence Indexing Connector, which enables search of the content of Excel workbooks and Reporting Services reports. (This capability existed in MOSS 2007, but was more cumbersome to implement. The search results in SharePoint 2010 are not only cooler, but more useful by describing whether the content is found in a table or a chart, for example.)This may yet be the dawning of the age of self-service BI - a phrase I've heard repeated from time to time over the last decade - but I think BI professionals are likely to stay busy for a long while, and need not start looking for a new line of work. Kummert repeatedly referenced strategic BI solutions in contrast to self-service BI to emphasize that self-service BI is not a replacement for the services that BI professionals provide. After all, self-service BI does not appear magically on user desktops (or whatever device they want to use). A supporting infrastructure is necessary, and grows in complexity in proportion to the need to simplify BI for users.It's one thing to hear the party line touted by Microsoft employees at the BI keynote, but it's another to hear from the people who are responsible for implementing and supporting it within an organization. Rob Collie (blog | twitter), Kasper de Jonge (blog | twitter), Vidas Matelis (site | twitter), and I were invited to join Andrew Brust (blog | twitter) as he led a Birds of a Feather session at TechEd entitled "PowerPivot: Is It the BI Deal-Changer for Developers and IT Pros?" I would single out the prevailing concern in this session as the issue of control. On one side of this issue were those who were concerned that they would lose control once PowerPivot is implemented. On the other side were those who believed that data should be freely accessible to users in PowerPivot, and even acknowledgment that users would get the data they want even if it meant they would have to manually enter into a workbook to have it ready for analysis. For another viewpoint on how PowerPivot played out at the conference, see Rob Collie's observations.Collaborative BII have been intrigued by the notion of collaborative BI for a very long time. Before I discovered BI, I was a Lotus Notes developer and later a manager of developers, working in a software company that enabled collaboration in the legal industry. Not only did I help create collaborative systems for our clients, I created a complete project management from the ground up to collaboratively manage our custom development work. In that case, collaboration involved my team, my client contacts, and me. I was also able to produce my own BI from that system as well, but didn't know that's what I was doing at the time. Only in recent years has SharePoint begun to catch up with the capabilities that I had with Lotus Notes more than a decade ago. Eventually, I had the opportunity at that job to formally investigate BI as another product offering for our software, and the rest - as they say - is history. I built my first data warehouse with Scott Cameron (who has also ventured into the authoring world by writing Analysis Services 2008 Step by Step and was at the BI Conference last week where I got to reminisce with him for a bit) and that began a career that I never imagined at the time.Fast forward to 2010, and I'm still lauding the virtues of collaborative BI, if only the tools will catch up to my vision! Thus, I was anxious to see what Donald Farmer (blog | twitter) and Rita Sallam of Gartner had to say on the subject in their session "Collaborative Decision Making." As I suspected, the tools aren't quite there yet, but the vendors are moving in the right direction. One thing I liked about this session was a non-Microsoft perspective of the state of the industry with regard to collaborative BI. In addition, this session included a better demonstration of SharePoint collaborative BI capabilities than appeared in the BI keynote. Check out the video in the link to the session to see the demonstration. One of the use cases that was demonstrated was linking from information to a person, because, as Donald put it, "People don't trust data, they trust people."The Microsoft BI Stack in GeneralA question I hear all the time from students when I'm teaching is how to know what tools to use when there is overlap between products in the BI stack. I've never taken the time to codify my thoughts on the subject, but saw that my friend Dan Bulos provided good insight on this topic from a variety of perspectives in his session, "So Many BI Tools, So Little Time." I thought one of his best points was that ideally you should be able to design in your tool of choice, and then deploy to your tool of choice. Unfortunately, the ideal is yet to become real across the platform. The closest we come is with the RDL in Reporting Services which can be produced from two different tools (Report Builder or Business Intelligence Development Studio's Report Designer), manually, or by a third-party or custom application. I have touted the idea for years (and publicly said so about 5 years ago) that eventually more products would be RDL producers or consumers, but we aren't there yet. Maybe in another 5 years.Another interesting session that covered the BI stack against a backdrop of competitive products was delivered by Andrew Brust. Andrew did a marvelous job of consolidating a lot of information in a way that clearly communicated how various vendors' offerings compared to the Microsoft BI stack. He also made a particularly compelling argument about how the existence of an ecosystem around the Microsoft BI stack provided innovation and opportunities lacking for other vendors. Check out his presentation, "How Does the Microsoft BI Stack...Stack Up?"Expo HallI had planned to spend more time in the Expo Hall to see who was doing new things with the BI stack, but didn't manage to get very far. Each time I set out on an exploratory mission, I got caught up in some fascinating conversations with one or more of my peers. I find interacting with people that I meet at conferences just as important as attending sessions to learn something new. There were a couple of items that really caught me eye, however, that I'll share here.Pragmatic Works. Whether you develop SSIS packages, build SSAS cubes, or author SSRS reports (or all of the above), you really must take a look at BI Documenter. Brian Knight (twitter) walked me through the key features, and I must say I was impressed. Once you've seen what this product can do, you won't want to document your BI projects any other way. You can download a free single-user database edition, or choose from more feature-rich standard or professional editions.Microsoft Press ebooks. I also stopped by the O'Reilly Media booth to meet some folks that one of my acquisitions editors at Microsoft Press recommended. In case you haven't heard, Microsoft Press has partnered with O'Reilly Media for distribution and publishing. Apart from my interest in learning more about O'Reilly Media as an author, an advertisement in their booth caught me eye which I think is a really great move. When you buy Microsoft Press ebooks through the O'Reilly web site, you can receive it in any (or all) of the following formats where possible: PDF, epub, .mobi for Kindle and .apk for Android. You also have lifetime DRM-free access to the ebooks. As someone who is an avid collector of books, I fnd myself running out of room for storage. In addition, I travel a lot, and it's hard to lug my reference library with me. Today's e-reader options make the move to digital books a more viable way to grow my library. Having a variety of formats means I am not limited to a single device, and lifetime access means I don't have to worry about keeping track of where I've stored my files. Because the e-books are DRM-free, I can copy and paste when I'm compiling notes, and I can print pages when necessary. That's a winning combination in my mind!Overall, I was pleased with the BI conference. There were many more sessions that I couldn't attend, either because the room was full when I got there or there were multiple sessions running concurrently that I wanted to see. Fortunately, many of the sessions are accessible for viewing online at http://www.msteched.com/2010/NorthAmerica along with the TechEd sessions. You can spot the BI sessions by the yellow skyline on the title slide of the presentation as shown below. Share this post: email it! | bookmark it! | digg it! | reddit! | kick it! | live it!

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  • How to manage maintenance/bug-fix branches in Subversion when setup projects need to be built?

    - by Mike Spross
    We have a suite of related products written in VB6, with some C# and VB.NET projects, and all the source is kept in a single Subversion repository. We haven't been using branches in Subversion (although we do tag releases now), and simply do all development in trunk, creating new releases when the trunk is stable enough. This causes no end of grief when we release a new version, issues are found with it, and we have already begun working on new features or major changes to the trunk. In the past, we would address this in one of two ways, depending on the severity of the issues and how stable we thought the trunk was: Hurry to stabilize the trunk, fix the issues, and then release a maintenance update based on the HEAD revision, but this had the side effect of releases that fixed the bugs but introduced new issues because of half-finished features or bugfixes that were in trunk. Make customers wait until the next official release, which is usually a few months. We want to change our policies to better deal with this situation. I was considering creating a "maintenance branch" in Subversion whenever I tag an official release. Then, new development would continue in trunk, and I can periodically merge specific fixes from trunk into the maintenance branch, and create a maintenance release when enough fixes are accumulated, while we continue to work on the next major update in parallel. I know we could also have a more stable trunk and create a branch for new updates instead, but keeping current development in trunk seems simpler to me. The major problem is that while we can easily branch the source code from a release tag and recompile it to get the binaries for that release, I'm not sure how to handle the setup and installer projects. We use QSetup to create all of our setup programs, and right now when we need to modify a setup project, we just edit the project file in-place (all the setup projects and any dependencies that we don't compile ourselves are stored on a separate server, and we make sure to always compile the setup projects on that machine only). However, since we may add or remove files to the setup as our code changes, there is no guarantee that today's setup projects will work with yesterday's source code. I was going to put all the QSetup projects in Subversion to deal with this, but I see some problems with this approach. I want the creation of setup programs to be as automated as possible, and at the very least, I want a separate build machine where I can build the release that I want (grabbing the code from Subversion first), grab the setup project for that release from Subversion, recompile the setup, and then copy the setup to another place on the network for QA testing and eventual release to customers. However, when someone needs to change a setup project (to add a new dependency that trunk now requires or to make other changes), there is a problem. If they treat it like a source file and check it out on their own machine to edit it, they won't be able to add files to the project unless they first copy the files they need to add to the build machine (so they are available to other developers), then copy all the other dependencies from the build machine to their machine, making sure to match the folder structure exactly. The issue here is that QSetup uses absolute paths for any files added to a setup project. However, this means installing a bunch of setup dependencies onto development machines, which seems messy (and which could destabilize the development environment if someone accidentally runs the setup project on their machine). Also, how do we manage third-party dependencies? For example, if the current maintenance branch used MSXML 3.0 and the trunk now requires MSXML 4.0, we can't go back and create a maintenance release if we have already replaced the MSXML library on the build machine with the latest version (assuming both versions have the same filename). The only solution I can think is to either put all the third-party dependencies in Subversion along with the source code, or to make sure we put different library versions in separate folders (i.e. C:\Setup\Dependencies\MSXML\v3.0 and C:\Setup\Dependencies\MSXML\v4.0). Is one way "better" or more common than the other? Are there any best practices for dealing with this situation? Basically, if we release v2.0 of our software, we want to be able to release v2.0.1, v2.0.2, and v.2.0.3 while we work on v2.1, but the whole setup/installation project and setup dependency issue is making this more complicated than the typical "just create a branch in Subversion and recompile as needed" answer.

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  • How to manage maintenance/bug-fix branches in Subversion when third-party installers are involved?

    - by Mike Spross
    We have a suite of related products written in VB6, with some C# and VB.NET projects, and all the source is kept in a single Subversion repository. We haven't been using branches in Subversion (although we do tag releases now), and simply do all development in trunk, creating new releases when the trunk is stable enough. This causes no end of grief when we release a new version, issues are found with it, and we have already begun working on new features or major changes to the trunk. In the past, we would address this in one of two ways, depending on the severity of the issues and how stable we thought the trunk was: Hurry to stabilize the trunk, fix the issues, and then release a maintenance update based on the HEAD revision, but this had the side effect of releases that fixed the bugs but introduced new issues because of half-finished features or bugfixes that were in trunk. Make customers wait until the next official release, which is usually a few months. We want to change our policies to better deal with this situation. I was considering creating a "maintenance branch" in Subversion whenever I tag an official release. Then, new development would continue in trunk, and I can periodically merge specific fixes from trunk into the maintenance branch, and create a maintenance release when enough fixes are accumulated, while we continue to work on the next major update in parallel. I know we could also have a more stable trunk and create a branch for new updates instead, but keeping current development in trunk seems simpler to me. The major problem is that while we can easily branch the source code from a release tag and recompile it to get the binaries for that release, I'm not sure how to handle the setup and installer projects. We use QSetup to create all of our setup programs, and right now when we need to modify a setup project, we just edit the project file in-place (all the setup projects and any dependencies that we don't compile ourselves are stored on a separate server, and we make sure to always compile the setup projects on that machine only). However, since we may add or remove files to the setup as our code changes, there is no guarantee that today's setup projects will work with yesterday's source code. I was going to put all the QSetup projects in Subversion to deal with this, but I see some problems with this approach. I want the creation of setup programs to be as automated as possible, and at the very least, I want a separate build machine where I can build the release that I want (grabbing the code from Subversion first), grab the setup project for that release from Subversion, recompile the setup, and then copy the setup to another place on the network for QA testing and eventual release to customers. However, when someone needs to change a setup project (to add a new dependency that trunk now requires or to make other changes), there is a problem. If they treat it like a source file and check it out on their own machine to edit it, they won't be able to add files to the project unless they first copy the files they need to add to the build machine (so they are available to other developers), then copy all the other dependencies from the build machine to their machine, making sure to match the folder structure exactly. The issue here is that QSetup uses absolute paths for any files added to a setup project. However, this means installing a bunch of setup dependencies onto development machines, which seems messy (and which could destabilize the development environment if someone accidentally runs the setup project on their machine). Also, how do we manage third-party dependencies? For example, if the current maintenance branch used MSXML 3.0 and the trunk now requires MSXML 4.0, we can't go back and create a maintenance release if we have already replaced the MSXML library on the build machine with the latest version (assuming both versions have the same filename). The only solution I can think is to either put all the third-party dependencies in Subversion along with the source code, or to make sure we put different library versions in separate folders (i.e. C:\Setup\Dependencies\MSXML\v3.0 and C:\Setup\Dependencies\MSXML\v4.0). Is one way "better" or more common than the other? Are there any best practices for dealing with this situation? Basically, if we release v2.0 of our software, we want to be able to release v2.0.1, v2.0.2, and v.2.0.3 while we work on v2.1, but the whole setup/installation project and setup dependency issue is making this more complicated than the the typical "just create a branch in Subversion and recompile as needed" answer.

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  • Lighttpd not cleanly restarting (address already in use)

    - by NilObject
    When doing a dist-upgrade recently, my lighttpd-1.4.19 install on Ubuntu 8.0.4 has begun failing to restart or reload properly with the /etc/init.d/lighttpd restart command. ~$ sudo /etc/init.d/lighttpd restart * Stopping web server lighttpd ...done. * Starting web server lighttpd 2009-06-13 04:06:36: (network.c.300) can't bind to port: 80 Address already in use ...fail! The same error occurs when I do a reload. The way I get around it is to kill lighttpd and then issue the start command, but it seems like I shouldn't have to do that :) I've looked at my config files, and can't spot any immediate errors. Does anyone have any ideas what can be causing this error? This seems to be the latest version as of writing this question that is available via the apt-get route. My config file is: # Debian lighttpd configuration file # ############ Options you really have to take care of #################### ## modules to load # mod_access, mod_accesslog and mod_alias are loaded by default # all other module should only be loaded if neccesary # - saves some time # - saves memory server.modules = ( "mod_access", "mod_alias", "mod_accesslog", "mod_compress", "mod_fastcgi", "mod_rewrite", "mod_redirect", ) ## a static document-root, for virtual-hosting take look at the ## server.virtual-* options server.document-root = "/var/www/" ## where to send error-messages to server.errorlog = "/var/log/lighttpd/error.log" fastcgi.server = (".php" => (( "bin-path" => "/usr/bin/php5-cgi", "socket" => "/tmp/php.socket" ))) ## files to check for if .../ is requested index-file.names = ( "index.php", "index.html", "index.htm", "default.htm", "index.lighttpd.html" ) ## Use the "Content-Type" extended attribute to obtain mime type if possible # mimetype.use-xattr = "enable" #### accesslog module accesslog.filename = "/var/log/lighttpd/access.log" ## deny access the file-extensions # # ~ is for backupfiles from vi, emacs, joe, ... # .inc is often used for code includes which should in general not be part # of the document-root url.access-deny = ( "~", ".inc" ) ## # which extensions should not be handle via static-file transfer # # .php, .pl, .fcgi are most often handled by mod_fastcgi or mod_cgi static-file.exclude-extensions = ( ".php", ".pl", ".fcgi" ) mimetype.assign = ( ".pdf" => "application/pdf", ".sig" => "application/pgp-signature", ".spl" => "application/futuresplash", ".class" => "application/octet-stream", ".ps" => "application/postscript", ".torrent" => "application/x-bittorrent", ".dvi" => "application/x-dvi", ".gz" => "application/x-gzip", ".pac" => "application/x-ns-proxy-autoconfig", ".swf" => "application/x-shockwave-flash", ".tar.gz" => "application/x-tgz", ".tgz" => "application/x-tgz", ".tar" => "application/x-tar", ".zip" => "application/zip", ".mp3" => "audio/mpeg", ".m3u" => "audio/x-mpegurl", ".wma" => "audio/x-ms-wma", ".wax" => "audio/x-ms-wax", ".ogg" => "audio/x-wav", ".wav" => "audio/x-wav", ".gif" => "image/gif", ".jpg" => "image/jpeg", ".jpeg" => "image/jpeg", ".png" => "image/png", ".xbm" => "image/x-xbitmap", ".xpm" => "image/x-xpixmap", ".xwd" => "image/x-xwindowdump", ".css" => "text/css", ".html" => "text/html", ".htm" => "text/html", ".js" => "text/javascript", ".asc" => "text/plain", ".c" => "text/plain", ".conf" => "text/plain", ".text" => "text/plain", ".txt" => "text/plain", ".dtd" => "text/xml", ".xml" => "text/xml", ".rss" => "application/rss+xml", ".mpeg" => "video/mpeg", ".mpg" => "video/mpeg", ".mov" => "video/quicktime", ".qt" => "video/quicktime", ".avi" => "video/x-msvideo", ".asf" => "video/x-ms-asf", ".asx" => "video/x-ms-asf", ".wmv" => "video/x-ms-wmv", ".bz2" => "application/x-bzip", ".tbz" => "application/x-bzip-compressed-tar", ".tar.bz2" => "application/x-bzip-compressed-tar" ) include_shell "/usr/share/lighttpd/include-conf-enabled.pl" My /etc/init.d/lighttpd script is (untouched from installation): #!/bin/sh ### BEGIN INIT INFO # Provides: lighttpd # Required-Start: networking # Required-Stop: networking # Default-Start: 2 3 4 5 # Default-Stop: 0 1 6 # Short-Description: Start the lighttpd web server. ### END INIT INFO PATH=/sbin:/bin:/usr/sbin:/usr/bin DAEMON=/usr/sbin/lighttpd NAME=lighttpd DESC="web server" PIDFILE=/var/run/$NAME.pid SCRIPTNAME=/etc/init.d/$NAME ENV="env -i LANG=C PATH=/usr/local/bin:/usr/bin:/bin" SSD="/sbin/start-stop-daemon" DAEMON_OPTS="-f /etc/lighttpd/lighttpd.conf" test -x $DAEMON || exit 0 set -e # be sure there is a /var/run/lighttpd, even with tmpfs mkdir -p /var/run/lighttpd > /dev/null 2> /dev/null chown www-data:www-data /var/run/lighttpd chmod 0750 /var/run/lighttpd . /lib/lsb/init-functions case "$1" in start) log_daemon_msg "Starting $DESC" $NAME if ! $ENV $SSD --start --quiet\ --pidfile $PIDFILE --exec $DAEMON -- $DAEMON_OPTS ; then log_end_msg 1 else log_end_msg 0 fi ;; stop) log_daemon_msg "Stopping $DESC" $NAME if $SSD --quiet --stop --oknodo --retry 30\ --pidfile $PIDFILE --exec $DAEMON; then rm -f $PIDFILE log_end_msg 0 else log_end_msg 1 fi ;; reload) log_daemon_msg "Reloading $DESC configuration" $NAME if $SSD --stop --signal 2 --oknodo --retry 30\ --quiet --pidfile $PIDFILE --exec $DAEMON; then if $ENV $SSD --start --quiet \ --pidfile $PIDFILE --exec $DAEMON -- $DAEMON_OPTS ; then log_end_msg 0 else log_end_msg 1 fi else log_end_msg 1 fi ;; restart|force-reload) $0 stop [ -r $PIDFILE ] && while pidof lighttpd |\ grep -q `cat $PIDFILE 2>/dev/null` 2>/dev/null ; do sleep 1; done $0 start ;; *) echo "Usage: $SCRIPTNAME {start|stop|restart|reload|force-reload}" >&2 exit 1 ;; esac exit 0

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  • UITableView not displaying parsed data

    - by Graeme
    I have a UITableView which is setup in Interface Builder and connected properly to its class in Xcode. I also have a "Importer" Class which downloads and parses an RSS feed and stores the information in an NSMutableArray. However I have verified the parsing is working properly (using breakpoints and NSlog) but no data is showing in the UITable View. Any ideas as to what the problem could be? I'm almost out of them. It's based on the XML performance Apple example. Here's the code for TableView.h: #import <UIKit/UIKit.h> #import "IncidentsImporter.h" @class SongDetailsController; @interface CurrentIncidentsTableViewController : UITableViewController <IncidentsImporterDelegate>{ NSMutableArray *incidents; SongDetailsController *detailController; UITableView *ctableView; IncidentsImporter *parser; } @property (nonatomic, retain) NSMutableArray *incidents; @property (nonatomic, retain, readonly) SongDetailsController *detailController; @property (nonatomic, retain) IncidentsImporter *parser; @property (nonatomic, retain) IBOutlet UITableView *ctableView; // Called by the ParserChoiceViewController based on the selected parser type. - (void)beginParsing; @end And the code for .m: #import "CurrentIncidentsTableViewController.h" #import "SongDetailsController.h" #import "Incident.h" @implementation CurrentIncidentsTableViewController @synthesize ctableView, incidents, parser, detailController; #pragma mark - #pragma mark View lifecycle - (void)viewDidLoad { [super viewDidLoad]; self.parser = [[IncidentsImporter alloc] init]; parser.delegate = self; [parser start]; UIBarButtonItem *refreshButton = [[UIBarButtonItem alloc] initWithBarButtonSystemItem:UIBarButtonSystemItemRefresh target:self action:@selector(beginParsing)]; self.navigationItem.rightBarButtonItem = refreshButton; [refreshButton release]; // Uncomment the following line to preserve selection between presentations. //self.clearsSelectionOnViewWillAppear = NO; // Uncomment the following line to display an Edit button in the navigation bar for this view controller. // self.navigationItem.rightBarButtonItem = self.editButtonItem; } - (void)viewWillAppear:(BOOL)animated { NSIndexPath *selectedRowIndexPath = [ctableView indexPathForSelectedRow]; if (selectedRowIndexPath != nil) { [ctableView deselectRowAtIndexPath:selectedRowIndexPath animated:NO]; } } // This method will be called repeatedly - once each time the user choses to parse. - (void)beginParsing { NSLog(@"Parsing has begun"); //self.navigationItem.rightBarButtonItem.enabled = NO; // Allocate the array for song storage, or empty the results of previous parses if (incidents == nil) { NSLog(@"Grabbing array"); self.incidents = [NSMutableArray array]; } else { [incidents removeAllObjects]; [ctableView reloadData]; } // Create the parser, set its delegate, and start it. self.parser = [[IncidentsImporter alloc] init]; parser.delegate = self; [parser start]; } /* - (void)viewDidAppear:(BOOL)animated { [super viewDidAppear:animated]; } */ /* - (void)viewWillDisappear:(BOOL)animated { [super viewWillDisappear:animated]; } */ /* - (void)viewDidDisappear:(BOOL)animated { [super viewDidDisappear:animated]; } */ - (BOOL)shouldAutorotateToInterfaceOrientation:(UIInterfaceOrientation)interfaceOrientation { // Override to allow orientations other than the default portrait orientation. return YES; } #pragma mark - #pragma mark Table view data source - (NSInteger)numberOfSectionsInTableView:(UITableView *)tableView { // Return the number of sections. return 1; } - (NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section { // Return the number of rows in the section. return [incidents count]; } // Customize the appearance of table view cells. - (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath { NSLog(@"Table Cell Sought"); static NSString *kCellIdentifier = @"MyCell"; UITableViewCell *cell = [ctableView dequeueReusableCellWithIdentifier:kCellIdentifier]; if (cell == nil) { cell = [[[UITableViewCell alloc] initWithStyle:UITableViewCellStyleDefault reuseIdentifier:kCellIdentifier] autorelease]; cell.textLabel.font = [UIFont boldSystemFontOfSize:14.0]; cell.accessoryType = UITableViewCellAccessoryDisclosureIndicator; } cell.textLabel.text = @"Test";//[[incidents objectAtIndex:indexPath.row] title]; return cell; } /* // Override to support conditional editing of the table view. - (BOOL)tableView:(UITableView *)tableView canEditRowAtIndexPath:(NSIndexPath *)indexPath { // Return NO if you do not want the specified item to be editable. return YES; } */ /* // Override to support editing the table view. - (void)tableView:(UITableView *)tableView commitEditingStyle:(UITableViewCellEditingStyle)editingStyle forRowAtIndexPath:(NSIndexPath *)indexPath { if (editingStyle == UITableViewCellEditingStyleDelete) { // Delete the row from the data source [tableView deleteRowsAtIndexPaths:[NSArray arrayWithObject:indexPath] withRowAnimation:YES]; } else if (editingStyle == UITableViewCellEditingStyleInsert) { // Create a new instance of the appropriate class, insert it into the array, and add a new row to the table view } } */ /* // Override to support rearranging the table view. - (void)tableView:(UITableView *)tableView moveRowAtIndexPath:(NSIndexPath *)fromIndexPath toIndexPath:(NSIndexPath *)toIndexPath { } */ /* // Override to support conditional rearranging of the table view. - (BOOL)tableView:(UITableView *)tableView canMoveRowAtIndexPath:(NSIndexPath *)indexPath { // Return NO if you do not want the item to be re-orderable. return YES; } */ #pragma mark - #pragma mark Table view delegate - (void)tableView:(UITableView *)tableView didSelectRowAtIndexPath:(NSIndexPath *)indexPath { self.detailController.incident = [incidents objectAtIndex:indexPath.row]; [self.navigationController pushViewController:self.detailController animated:YES]; } #pragma mark - #pragma mark Memory management - (void)didReceiveMemoryWarning { // Releases the view if it doesn't have a superview. [super didReceiveMemoryWarning]; // Relinquish ownership any cached data, images, etc that aren't in use. } - (void)viewDidUnload { // Relinquish ownership of anything that can be recreated in viewDidLoad or on demand. // For example: self.myOutlet = nil; } - (void)parserDidEndParsingData:(IncidentsImporter *)parser { [ctableView reloadData]; self.navigationItem.rightBarButtonItem.enabled = YES; self.parser = nil; } - (void)parser:(IncidentsImporter *)parser didParseIncidents:(NSArray *)parsedIncidents { //[incidents addObjectsFromArray: parsedIncidents]; // Three scroll view properties are checked to keep the user interface smooth during parse. When new objects are delivered by the parser, the table view is reloaded to display them. If the table is reloaded while the user is scrolling, this can result in eratic behavior. dragging, tracking, and decelerating can be checked for this purpose. When the parser finishes, reloadData will be called in parserDidEndParsingData:, guaranteeing that all data will ultimately be displayed even if reloadData is not called in this method because of user interaction. if (!ctableView.dragging && !ctableView.tracking && !ctableView.decelerating) { self.title = [NSString stringWithFormat:NSLocalizedString(@"Top %d Songs", @"Top Songs format"), [parsedIncidents count]]; [ctableView reloadData]; } } - (void)parser:(IncidentsImporter *)parser didFailWithError:(NSError *)error { // handle errors as appropriate to your application... } - (void)dealloc { [super dealloc]; } @end

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  • Agile Development

    - by James Oloo Onyango
    Alot of literature has and is being written about agile developement and its surrounding philosophies. In my quest to find the best way to express the importance of agile methodologies, i have found Robert C. Martin's "A Satire Of Two Companies" to be both the most concise and thorough! Enjoy the read! Rufus Inc Project Kick Off Your name is Bob. The date is January 3, 2001, and your head still aches from the recent millennial revelry. You are sitting in a conference room with several managers and a group of your peers. You are a project team leader. Your boss is there, and he has brought along all of his team leaders. His boss called the meeting. "We have a new project to develop," says your boss's boss. Call him BB. The points in his hair are so long that they scrape the ceiling. Your boss's points are just starting to grow, but he eagerly awaits the day when he can leave Brylcream stains on the acoustic tiles. BB describes the essence of the new market they have identified and the product they want to develop to exploit this market. "We must have this new project up and working by fourth quarter October 1," BB demands. "Nothing is of higher priority, so we are cancelling your current project." The reaction in the room is stunned silence. Months of work are simply going to be thrown away. Slowly, a murmur of objection begins to circulate around the conference table.   His points give off an evil green glow as BB meets the eyes of everyone in the room. One by one, that insidious stare reduces each attendee to quivering lumps of protoplasm. It is clear that he will brook no discussion on this matter. Once silence has been restored, BB says, "We need to begin immediately. How long will it take you to do the analysis?" You raise your hand. Your boss tries to stop you, but his spitwad misses you and you are unaware of his efforts.   "Sir, we can't tell you how long the analysis will take until we have some requirements." "The requirements document won't be ready for 3 or 4 weeks," BB says, his points vibrating with frustration. "So, pretend that you have the requirements in front of you now. How long will you require for analysis?" No one breathes. Everyone looks around to see whether anyone has some idea. "If analysis goes beyond April 1, we have a problem. Can you finish the analysis by then?" Your boss visibly gathers his courage: "We'll find a way, sir!" His points grow 3 mm, and your headache increases by two Tylenol. "Good." BB smiles. "Now, how long will it take to do the design?" "Sir," you say. Your boss visibly pales. He is clearly worried that his 3 mms are at risk. "Without an analysis, it will not be possible to tell you how long design will take." BB's expression shifts beyond austere.   "PRETEND you have the analysis already!" he says, while fixing you with his vacant, beady little eyes. "How long will it take you to do the design?" Two Tylenol are not going to cut it. Your boss, in a desperate attempt to save his new growth, babbles: "Well, sir, with only six months left to complete the project, design had better take no longer than 3 months."   "I'm glad you agree, Smithers!" BB says, beaming. Your boss relaxes. He knows his points are secure. After a while, he starts lightly humming the Brylcream jingle. BB continues, "So, analysis will be complete by April 1, design will be complete by July 1, and that gives you 3 months to implement the project. This meeting is an example of how well our new consensus and empowerment policies are working. Now, get out there and start working. I'll expect to see TQM plans and QIT assignments on my desk by next week. Oh, and don't forget that your crossfunctional team meetings and reports will be needed for next month's quality audit." "Forget the Tylenol," you think to yourself as you return to your cubicle. "I need bourbon."   Visibly excited, your boss comes over to you and says, "Gosh, what a great meeting. I think we're really going to do some world shaking with this project." You nod in agreement, too disgusted to do anything else. "Oh," your boss continues, "I almost forgot." He hands you a 30-page document. "Remember that the SEI is coming to do an evaluation next week. This is the evaluation guide. You need to read through it, memorize it, and then shred it. It tells you how to answer any questions that the SEI auditors ask you. It also tells you what parts of the building you are allowed to take them to and what parts to avoid. We are determined to be a CMM level 3 organization by June!"   You and your peers start working on the analysis of the new project. This is difficult because you have no requirements. But from the 10-minute introduction given by BB on that fateful morning, you have some idea of what the product is supposed to do.   Corporate process demands that you begin by creating a use case document. You and your team begin enumerating use cases and drawing oval and stick diagrams. Philosophical debates break out among the team members. There is disagreement as to whether certain use cases should be connected with <<extends>> or <<includes>> relationships. Competing models are created, but nobody knows how to evaluate them. The debate continues, effectively paralyzing progress.   After a week, somebody finds the iceberg.com Web site, which recommends disposing entirely of <<extends>> and <<includes>> and replacing them with <<precedes>> and <<uses>>. The documents on this Web site, authored by Don Sengroiux, describes a method known as stalwart-analysis, which claims to be a step-by-step method for translating use cases into design diagrams. More competing use case models are created using this new scheme, but again, people can't agree on how to evaluate them. The thrashing continues. More and more, the use case meetings are driven by emotion rather than by reason. If it weren't for the fact that you don't have requirements, you'd be pretty upset by the lack of progress you are making. The requirements document arrives on February 15. And then again on February 20, 25, and every week thereafter. Each new version contradicts the previous one. Clearly, the marketing folks who are writing the requirements, empowered though they might be, are not finding consensus.   At the same time, several new competing use case templates have been proposed by the various team members. Each template presents its own particularly creative way of delaying progress. The debates rage on. On March 1, Prudence Putrigence, the process proctor, succeeds in integrating all the competing use case forms and templates into a single, all-encompassing form. Just the blank form is 15 pages long. She has managed to include every field that appeared on all the competing templates. She also presents a 159- page document describing how to fill out the use case form. All current use cases must be rewritten according to the new standard.   You marvel to yourself that it now requires 15 pages of fill-in-the-blank and essay questions to answer the question: What should the system do when the user presses Return? The corporate process (authored by L. E. Ott, famed author of "Holistic Analysis: A Progressive Dialectic for Software Engineers") insists that you discover all primary use cases, 87 percent of all secondary use cases, and 36.274 percent of all tertiary use cases before you can complete analysis and enter the design phase. You have no idea what a tertiary use case is. So in an attempt to meet this requirement, you try to get your use case document reviewed by the marketing department, which you hope will know what a tertiary use case is.   Unfortunately, the marketing folks are too busy with sales support to talk to you. Indeed, since the project started, you have not been able to get a single meeting with marketing, which has provided a never-ending stream of changing and contradictory requirements documents.   While one team has been spinning endlessly on the use case document, another team has been working out the domain model. Endless variations of UML documents are pouring out of this team. Every week, the model is reworked.   The team members can't decide whether to use <<interfaces>> or <<types>> in the model. A huge disagreement has been raging on the proper syntax and application of OCL. Others on the team just got back from a 5-day class on catabolism, and have been producing incredibly detailed and arcane diagrams that nobody else can fathom.   On March 27, with one week to go before analysis is to be complete, you have produced a sea of documents and diagrams but are no closer to a cogent analysis of the problem than you were on January 3. **** And then, a miracle happens.   **** On Saturday, April 1, you check your e-mail from home. You see a memo from your boss to BB. It states unequivocally that you are done with the analysis! You phone your boss and complain. "How could you have told BB that we were done with the analysis?" "Have you looked at a calendar lately?" he responds. "It's April 1!" The irony of that date does not escape you. "But we have so much more to think about. So much more to analyze! We haven't even decided whether to use <<extends>> or <<precedes>>!" "Where is your evidence that you are not done?" inquires your boss, impatiently. "Whaaa . . . ." But he cuts you off. "Analysis can go on forever; it has to be stopped at some point. And since this is the date it was scheduled to stop, it has been stopped. Now, on Monday, I want you to gather up all existing analysis materials and put them into a public folder. Release that folder to Prudence so that she can log it in the CM system by Monday afternoon. Then get busy and start designing."   As you hang up the phone, you begin to consider the benefits of keeping a bottle of bourbon in your bottom desk drawer. They threw a party to celebrate the on-time completion of the analysis phase. BB gave a colon-stirring speech on empowerment. And your boss, another 3 mm taller, congratulated his team on the incredible show of unity and teamwork. Finally, the CIO takes the stage to tell everyone that the SEI audit went very well and to thank everyone for studying and shredding the evaluation guides that were passed out. Level 3 now seems assured and will be awarded by June. (Scuttlebutt has it that managers at the level of BB and above are to receive significant bonuses once the SEI awards level 3.)   As the weeks flow by, you and your team work on the design of the system. Of course, you find that the analysis that the design is supposedly based on is flawedno, useless; no, worse than useless. But when you tell your boss that you need to go back and work some more on the analysis to shore up its weaker sections, he simply states, "The analysis phase is over. The only allowable activity is design. Now get back to it."   So, you and your team hack the design as best you can, unsure of whether the requirements have been properly analyzed. Of course, it really doesn't matter much, since the requirements document is still thrashing with weekly revisions, and the marketing department still refuses to meet with you.     The design is a nightmare. Your boss recently misread a book named The Finish Line in which the author, Mark DeThomaso, blithely suggested that design documents should be taken down to code-level detail. "If we are going to be working at that level of detail," you ask, "why don't we simply write the code instead?" "Because then you wouldn't be designing, of course. And the only allowable activity in the design phase is design!" "Besides," he continues, "we have just purchased a companywide license for Dandelion! This tool enables 'Round the Horn Engineering!' You are to transfer all design diagrams into this tool. It will automatically generate our code for us! It will also keep the design diagrams in sync with the code!" Your boss hands you a brightly colored shrinkwrapped box containing the Dandelion distribution. You accept it numbly and shuffle off to your cubicle. Twelve hours, eight crashes, one disk reformatting, and eight shots of 151 later, you finally have the tool installed on your server. You consider the week your team will lose while attending Dandelion training. Then you smile and think, "Any week I'm not here is a good week." Design diagram after design diagram is created by your team. Dandelion makes it very difficult to draw these diagrams. There are dozens and dozens of deeply nested dialog boxes with funny text fields and check boxes that must all be filled in correctly. And then there's the problem of moving classes between packages. At first, these diagram are driven from the use cases. But the requirements are changing so often that the use cases rapidly become meaningless. Debates rage about whether VISITOR or DECORATOR design patterns should be used. One developer refuses to use VISITOR in any form, claiming that it's not a properly object-oriented construct. Someone refuses to use multiple inheritance, since it is the spawn of the devil. Review meetings rapidly degenerate into debates about the meaning of object orientation, the definition of analysis versus design, or when to use aggregation versus association. Midway through the design cycle, the marketing folks announce that they have rethought the focus of the system. Their new requirements document is completely restructured. They have eliminated several major feature areas and replaced them with feature areas that they anticipate customer surveys will show to be more appropriate. You tell your boss that these changes mean that you need to reanalyze and redesign much of the system. But he says, "The analysis phase is system. But he says, "The analysis phase is over. The only allowable activity is design. Now get back to it."   You suggest that it might be better to create a simple prototype to show to the marketing folks and even some potential customers. But your boss says, "The analysis phase is over. The only allowable activity is design. Now get back to it." Hack, hack, hack, hack. You try to create some kind of a design document that might reflect the new requirements documents. However, the revolution of the requirements has not caused them to stop thrashing. Indeed, if anything, the wild oscillations of the requirements document have only increased in frequency and amplitude.   You slog your way through them.   On June 15, the Dandelion database gets corrupted. Apparently, the corruption has been progressive. Small errors in the DB accumulated over the months into bigger and bigger errors. Eventually, the CASE tool just stopped working. Of course, the slowly encroaching corruption is present on all the backups. Calls to the Dandelion technical support line go unanswered for several days. Finally, you receive a brief e-mail from Dandelion, informing you that this is a known problem and that the solution is to purchase the new version, which they promise will be ready some time next quarter, and then reenter all the diagrams by hand.   ****   Then, on July 1 another miracle happens! You are done with the design!   Rather than go to your boss and complain, you stock your middle desk drawer with some vodka.   **** They threw a party to celebrate the on-time completion of the design phase and their graduation to CMM level 3. This time, you find BB's speech so stirring that you have to use the restroom before it begins. New banners and plaques are all over your workplace. They show pictures of eagles and mountain climbers, and they talk about teamwork and empowerment. They read better after a few scotches. That reminds you that you need to clear out your file cabinet to make room for the brandy. You and your team begin to code. But you rapidly discover that the design is lacking in some significant areas. Actually, it's lacking any significance at all. You convene a design session in one of the conference rooms to try to work through some of the nastier problems. But your boss catches you at it and disbands the meeting, saying, "The design phase is over. The only allowable activity is coding. Now get back to it."   ****   The code generated by Dandelion is really hideous. It turns out that you and your team were using association and aggregation the wrong way, after all. All the generated code has to be edited to correct these flaws. Editing this code is extremely difficult because it has been instrumented with ugly comment blocks that have special syntax that Dandelion needs in order to keep the diagrams in sync with the code. If you accidentally alter one of these comments, the diagrams will be regenerated incorrectly. It turns out that "Round the Horn Engineering" requires an awful lot of effort. The more you try to keep the code compatible with Dandelion, the more errors Dandelion generates. In the end, you give up and decide to keep the diagrams up to date manually. A second later, you decide that there's no point in keeping the diagrams up to date at all. Besides, who has time?   Your boss hires a consultant to build tools to count the number of lines of code that are being produced. He puts a big thermometer graph on the wall with the number 1,000,000 on the top. Every day, he extends the red line to show how many lines have been added. Three days after the thermometer appears on the wall, your boss stops you in the hall. "That graph isn't growing quickly enough. We need to have a million lines done by October 1." "We aren't even sh-sh-sure that the proshect will require a m-million linezh," you blather. "We have to have a million lines done by October 1," your boss reiterates. His points have grown again, and the Grecian formula he uses on them creates an aura of authority and competence. "Are you sure your comment blocks are big enough?" Then, in a flash of managerial insight, he says, "I have it! I want you to institute a new policy among the engineers. No line of code is to be longer than 20 characters. Any such line must be split into two or more preferably more. All existing code needs to be reworked to this standard. That'll get our line count up!"   You decide not to tell him that this will require two unscheduled work months. You decide not to tell him anything at all. You decide that intravenous injections of pure ethanol are the only solution. You make the appropriate arrangements. Hack, hack, hack, and hack. You and your team madly code away. By August 1, your boss, frowning at the thermometer on the wall, institutes a mandatory 50-hour workweek.   Hack, hack, hack, and hack. By September 1st, the thermometer is at 1.2 million lines and your boss asks you to write a report describing why you exceeded the coding budget by 20 percent. He institutes mandatory Saturdays and demands that the project be brought back down to a million lines. You start a campaign of remerging lines. Hack, hack, hack, and hack. Tempers are flaring; people are quitting; QA is raining trouble reports down on you. Customers are demanding installation and user manuals; salespeople are demanding advance demonstrations for special customers; the requirements document is still thrashing, the marketing folks are complaining that the product isn't anything like they specified, and the liquor store won't accept your credit card anymore. Something has to give.    On September 15, BB calls a meeting. As he enters the room, his points are emitting clouds of steam. When he speaks, the bass overtones of his carefully manicured voice cause the pit of your stomach to roll over. "The QA manager has told me that this project has less than 50 percent of the required features implemented. He has also informed me that the system crashes all the time, yields wrong results, and is hideously slow. He has also complained that he cannot keep up with the continuous train of daily releases, each more buggy than the last!" He stops for a few seconds, visibly trying to compose himself. "The QA manager estimates that, at this rate of development, we won't be able to ship the product until December!" Actually, you think it's more like March, but you don't say anything. "December!" BB roars with such derision that people duck their heads as though he were pointing an assault rifle at them. "December is absolutely out of the question. Team leaders, I want new estimates on my desk in the morning. I am hereby mandating 65-hour work weeks until this project is complete. And it better be complete by November 1."   As he leaves the conference room, he is heard to mutter: "Empowermentbah!" * * * Your boss is bald; his points are mounted on BB's wall. The fluorescent lights reflecting off his pate momentarily dazzle you. "Do you have anything to drink?" he asks. Having just finished your last bottle of Boone's Farm, you pull a bottle of Thunderbird from your bookshelf and pour it into his coffee mug. "What's it going to take to get this project done? " he asks. "We need to freeze the requirements, analyze them, design them, and then implement them," you say callously. "By November 1?" your boss exclaims incredulously. "No way! Just get back to coding the damned thing." He storms out, scratching his vacant head.   A few days later, you find that your boss has been transferred to the corporate research division. Turnover has skyrocketed. Customers, informed at the last minute that their orders cannot be fulfilled on time, have begun to cancel their orders. Marketing is re-evaluating whether this product aligns with the overall goals of the company. Memos fly, heads roll, policies change, and things are, overall, pretty grim. Finally, by March, after far too many sixty-five hour weeks, a very shaky version of the software is ready. In the field, bug-discovery rates are high, and the technical support staff are at their wits' end, trying to cope with the complaints and demands of the irate customers. Nobody is happy.   In April, BB decides to buy his way out of the problem by licensing a product produced by Rupert Industries and redistributing it. The customers are mollified, the marketing folks are smug, and you are laid off.     Rupert Industries: Project Alpha   Your name is Robert. The date is January 3, 2001. The quiet hours spent with your family this holiday have left you refreshed and ready for work. You are sitting in a conference room with your team of professionals. The manager of the division called the meeting. "We have some ideas for a new project," says the division manager. Call him Russ. He is a high-strung British chap with more energy than a fusion reactor. He is ambitious and driven but understands the value of a team. Russ describes the essence of the new market opportunity the company has identified and introduces you to Jane, the marketing manager, who is responsible for defining the products that will address it. Addressing you, Jane says, "We'd like to start defining our first product offering as soon as possible. When can you and your team meet with me?" You reply, "We'll be done with the current iteration of our project this Friday. We can spare a few hours for you between now and then. After that, we'll take a few people from the team and dedicate them to you. We'll begin hiring their replacements and the new people for your team immediately." "Great," says Russ, "but I want you to understand that it is critical that we have something to exhibit at the trade show coming up this July. If we can't be there with something significant, we'll lose the opportunity."   "I understand," you reply. "I don't yet know what it is that you have in mind, but I'm sure we can have something by July. I just can't tell you what that something will be right now. In any case, you and Jane are going to have complete control over what we developers do, so you can rest assured that by July, you'll have the most important things that can be accomplished in that time ready to exhibit."   Russ nods in satisfaction. He knows how this works. Your team has always kept him advised and allowed him to steer their development. He has the utmost confidence that your team will work on the most important things first and will produce a high-quality product.   * * *   "So, Robert," says Jane at their first meeting, "How does your team feel about being split up?" "We'll miss working with each other," you answer, "but some of us were getting pretty tired of that last project and are looking forward to a change. So, what are you people cooking up?" Jane beams. "You know how much trouble our customers currently have . . ." And she spends a half hour or so describing the problem and possible solution. "OK, wait a second" you respond. "I need to be clear about this." And so you and Jane talk about how this system might work. Some of her ideas aren't fully formed. You suggest possible solutions. She likes some of them. You continue discussing.   During the discussion, as each new topic is addressed, Jane writes user story cards. Each card represents something that the new system has to do. The cards accumulate on the table and are spread out in front of you. Both you and Jane point at them, pick them up, and make notes on them as you discuss the stories. The cards are powerful mnemonic devices that you can use to represent complex ideas that are barely formed.   At the end of the meeting, you say, "OK, I've got a general idea of what you want. I'm going to talk to the team about it. I imagine they'll want to run some experiments with various database structures and presentation formats. Next time we meet, it'll be as a group, and we'll start identifying the most important features of the system."   A week later, your nascent team meets with Jane. They spread the existing user story cards out on the table and begin to get into some of the details of the system. The meeting is very dynamic. Jane presents the stories in the order of their importance. There is much discussion about each one. The developers are concerned about keeping the stories small enough to estimate and test. So they continually ask Jane to split one story into several smaller stories. Jane is concerned that each story have a clear business value and priority, so as she splits them, she makes sure that this stays true.   The stories accumulate on the table. Jane writes them, but the developers make notes on them as needed. Nobody tries to capture everything that is said; the cards are not meant to capture everything but are simply reminders of the conversation.   As the developers become more comfortable with the stories, they begin writing estimates on them. These estimates are crude and budgetary, but they give Jane an idea of what the story will cost.   At the end of the meeting, it is clear that many more stories could be discussed. It is also clear that the most important stories have been addressed and that they represent several months worth of work. Jane closes the meeting by taking the cards with her and promising to have a proposal for the first release in the morning.   * * *   The next morning, you reconvene the meeting. Jane chooses five cards and places them on the table. "According to your estimates, these cards represent about one perfect team-week's worth of work. The last iteration of the previous project managed to get one perfect team-week done in 3 real weeks. If we can get these five stories done in 3 weeks, we'll be able to demonstrate them to Russ. That will make him feel very comfortable about our progress." Jane is pushing it. The sheepish look on her face lets you know that she knows it too. You reply, "Jane, this is a new team, working on a new project. It's a bit presumptuous to expect that our velocity will be the same as the previous team's. However, I met with the team yesterday afternoon, and we all agreed that our initial velocity should, in fact, be set to one perfectweek for every 3 real-weeks. So you've lucked out on this one." "Just remember," you continue, "that the story estimates and the story velocity are very tentative at this point. We'll learn more when we plan the iteration and even more when we implement it."   Jane looks over her glasses at you as if to say "Who's the boss around here, anyway?" and then smiles and says, "Yeah, don't worry. I know the drill by now."Jane then puts 15 more cards on the table. She says, "If we can get all these cards done by the end of March, we can turn the system over to our beta test customers. And we'll get good feedback from them."   You reply, "OK, so we've got our first iteration defined, and we have the stories for the next three iterations after that. These four iterations will make our first release."   "So," says Jane, can you really do these five stories in the next 3 weeks?" "I don't know for sure, Jane," you reply. "Let's break them down into tasks and see what we get."   So Jane, you, and your team spend the next several hours taking each of the five stories that Jane chose for the first iteration and breaking them down into small tasks. The developers quickly realize that some of the tasks can be shared between stories and that other tasks have commonalities that can probably be taken advantage of. It is clear that potential designs are popping into the developers' heads. From time to time, they form little discussion knots and scribble UML diagrams on some cards.   Soon, the whiteboard is filled with the tasks that, once completed, will implement the five stories for this iteration. You start the sign-up process by saying, "OK, let's sign up for these tasks." "I'll take the initial database generation." Says Pete. "That's what I did on the last project, and this doesn't look very different. I estimate it at two of my perfect workdays." "OK, well, then, I'll take the login screen," says Joe. "Aw, darn," says Elaine, the junior member of the team, "I've never done a GUI, and kinda wanted to try that one."   "Ah, the impatience of youth," Joe says sagely, with a wink in your direction. "You can assist me with it, young Jedi." To Jane: "I think it'll take me about three of my perfect workdays."   One by one, the developers sign up for tasks and estimate them in terms of their own perfect workdays. Both you and Jane know that it is best to let the developers volunteer for tasks than to assign the tasks to them. You also know full well that you daren't challenge any of the developers' estimates. You know these people, and you trust them. You know that they are going to do the very best they can.   The developers know that they can't sign up for more perfect workdays than they finished in the last iteration they worked on. Once each developer has filled his or her schedule for the iteration, they stop signing up for tasks.   Eventually, all the developers have stopped signing up for tasks. But, of course, tasks are still left on the board.   "I was worried that that might happen," you say, "OK, there's only one thing to do, Jane. We've got too much to do in this iteration. What stories or tasks can we remove?" Jane sighs. She knows that this is the only option. Working overtime at the beginning of a project is insane, and projects where she's tried it have not fared well.   So Jane starts to remove the least-important functionality. "Well, we really don't need the login screen just yet. We can simply start the system in the logged-in state." "Rats!" cries Elaine. "I really wanted to do that." "Patience, grasshopper." says Joe. "Those who wait for the bees to leave the hive will not have lips too swollen to relish the honey." Elaine looks confused. Everyone looks confused. "So . . .," Jane continues, "I think we can also do away with . . ." And so, bit by bit, the list of tasks shrinks. Developers who lose a task sign up for one of the remaining ones.   The negotiation is not painless. Several times, Jane exhibits obvious frustration and impatience. Once, when tensions are especially high, Elaine volunteers, "I'll work extra hard to make up some of the missing time." You are about to correct her when, fortunately, Joe looks her in the eye and says, "When once you proceed down the dark path, forever will it dominate your destiny."   In the end, an iteration acceptable to Jane is reached. It's not what Jane wanted. Indeed, it is significantly less. But it's something the team feels that can be achieved in the next 3 weeks.   And, after all, it still addresses the most important things that Jane wanted in the iteration. "So, Jane," you say when things had quieted down a bit, "when can we expect acceptance tests from you?" Jane sighs. This is the other side of the coin. For every story the development team implements,   Jane must supply a suite of acceptance tests that prove that it works. And the team needs these long before the end of the iteration, since they will certainly point out differences in the way Jane and the developers imagine the system's behaviour.   "I'll get you some example test scripts today," Jane promises. "I'll add to them every day after that. You'll have the entire suite by the middle of the iteration."   * * *   The iteration begins on Monday morning with a flurry of Class, Responsibilities, Collaborators sessions. By midmorning, all the developers have assembled into pairs and are rapidly coding away. "And now, my young apprentice," Joe says to Elaine, "you shall learn the mysteries of test-first design!"   "Wow, that sounds pretty rad," Elaine replies. "How do you do it?" Joe beams. It's clear that he has been anticipating this moment. "OK, what does the code do right now?" "Huh?" replied Elaine, "It doesn't do anything at all; there is no code."   "So, consider our task; can you think of something the code should do?" "Sure," Elaine said with youthful assurance, "First, it should connect to the database." "And thereupon, what must needs be required to connecteth the database?" "You sure talk weird," laughed Elaine. "I think we'd have to get the database object from some registry and call the Connect() method. "Ah, astute young wizard. Thou perceives correctly that we requireth an object within which we can cacheth the database object." "Is 'cacheth' really a word?" "It is when I say it! So, what test can we write that we know the database registry should pass?" Elaine sighs. She knows she'll just have to play along. "We should be able to create a database object and pass it to the registry in a Store() method. And then we should be able to pull it out of the registry with a Get() method and make sure it's the same object." "Oh, well said, my prepubescent sprite!" "Hay!" "So, now, let's write a test function that proves your case." "But shouldn't we write the database object and registry object first?" "Ah, you've much to learn, my young impatient one. Just write the test first." "But it won't even compile!" "Are you sure? What if it did?" "Uh . . ." "Just write the test, Elaine. Trust me." And so Joe, Elaine, and all the other developers began to code their tasks, one test case at a time. The room in which they worked was abuzz with the conversations between the pairs. The murmur was punctuated by an occasional high five when a pair managed to finish a task or a difficult test case.   As development proceeded, the developers changed partners once or twice a day. Each developer got to see what all the others were doing, and so knowledge of the code spread generally throughout the team.   Whenever a pair finished something significant whether a whole task or simply an important part of a task they integrated what they had with the rest of the system. Thus, the code base grew daily, and integration difficulties were minimized.   The developers communicated with Jane on a daily basis. They'd go to her whenever they had a question about the functionality of the system or the interpretation of an acceptance test case.   Jane, good as her word, supplied the team with a steady stream of acceptance test scripts. The team read these carefully and thereby gained a much better understanding of what Jane expected the system to do. By the beginning of the second week, there was enough functionality to demonstrate to Jane. She watched eagerly as the demonstration passed test case after test case. "This is really cool," Jane said as the demonstration finally ended. "But this doesn't seem like one-third of the tasks. Is your velocity slower than anticipated?"   You grimace. You'd been waiting for a good time to mention this to Jane but now she was forcing the issue. "Yes, unfortunately, we are going more slowly than we had expected. The new application server we are using is turning out to be a pain to configure. Also, it takes forever to reboot, and we have to reboot it whenever we make even the slightest change to its configuration."   Jane eyes you with suspicion. The stress of last Monday's negotiations had still not entirely dissipated. She says, "And what does this mean to our schedule? We can't slip it again, we just can't. Russ will have a fit! He'll haul us all into the woodshed and ream us some new ones."   You look Jane right in the eyes. There's no pleasant way to give someone news like this. So you just blurt out, "Look, if things keep going like they're going, we're not going to be done with everything by next Friday. Now it's possible that we'll figure out a way to go faster. But, frankly, I wouldn't depend on that. You should start thinking about one or two tasks that could be removed from the iteration without ruining the demonstration for Russ. Come hell or high water, we are going to give that demonstration on Friday, and I don't think you want us to choose which tasks to omit."   "Aw forchrisakes!" Jane barely manages to stifle yelling that last word as she stalks away, shaking her head. Not for the first time, you say to yourself, "Nobody ever promised me project management would be easy." You are pretty sure it won't be the last time, either.   Actually, things went a bit better than you had hoped. The team did, in fact, have to drop one task from the iteration, but Jane had chosen wisely, and the demonstration for Russ went without a hitch. Russ was not impressed with the progress, but neither was he dismayed. He simply said, "This is pretty good. But remember, we have to be able to demonstrate this system at the trade show in July, and at this rate, it doesn't look like you'll have all that much to show." Jane, whose attitude had improved dramatically with the completion of the iteration, responded to Russ by saying, "Russ, this team is working hard, and well. When July comes around, I am confident that we'll have something significant to demonstrate. It won't be everything, and some of it may be smoke and mirrors, but we'll have something."   Painful though the last iteration was, it had calibrated your velocity numbers. The next iteration went much better. Not because your team got more done than in the last iteration but simply because the team didn't have to remove any tasks or stories in the middle of the iteration.   By the start of the fourth iteration, a natural rhythm has been established. Jane, you, and the team know exactly what to expect from one another. The team is running hard, but the pace is sustainable. You are confident that the team can keep up this pace for a year or more.   The number of surprises in the schedule diminishes to near zero; however, the number of surprises in the requirements does not. Jane and Russ frequently look over the growing system and make recommendations or changes to the existing functionality. But all parties realize that these changes take time and must be scheduled. So the changes do not cause anyone's expectations to be violated. In March, there is a major demonstration of the system to the board of directors. The system is very limited and is not yet in a form good enough to take to the trade show, but progress is steady, and the board is reasonably impressed.   The second release goes even more smoothly than the first. By now, the team has figured out a way to automate Jane's acceptance test scripts. The team has also refactored the design of the system to the point that it is really easy to add new features and change old ones. The second release was done by the end of June and was taken to the trade show. It had less in it than Jane and Russ would have liked, but it did demonstrate the most important features of the system. Although customers at the trade show noticed that certain features were missing, they were very impressed overall. You, Russ, and Jane all returned from the trade show with smiles on your faces. You all felt as though this project was a winner.   Indeed, many months later, you are contacted by Rufus Inc. That company had been working on a system like this for its internal operations. Rufus has canceled the development of that system after a death-march project and is negotiating to license your technology for its environment.   Indeed, things are looking up!

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