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• Windows Azure Boot Camp coming to KC in April

  - by John Alexander

  Interested in getting up to speed on Windows Azure? Then check out this FREE boot camp, all across the US this   What is a Windows Azure Boot Camp? Windows Azure Boot Camp is a two day deep dive class to get you up to speed on developing for Windows Azure. The class includes a trainer with deep real world experience with Azure, as well as a series of labs so you can practice what you just learned. ABC is more than just a class, it is also an event in a box. If you don't see a class near you, then throw your own. We provide all of the materials and training you need to host your own class. This can be for your company, your customers, your friends, or even your family. Please let us know so we can give you all of the details.   Awesome. How much does it cost? Thanks to all of our fantabulous sponsors, this two day training event is FREE! We will provide drinks and snacks, but you will be on your own for lunch on both days. This is a training class after all.   How do I attend one? You can click here to register for the Kansas City event on April 8th and 9th or click here to see where else ABC will be… WHAT TO BRING – important!!!

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• Step Away From That Computer! You’re Not Qualified to Use It!

  - by Michael Sorens

  Most things tend to come with warnings and careful instructions these days, but sadly not one of the most ubiquitous appliances of all, your computer. If a chainsaw is missing its instructions, you’re well advised not to use it, even though you probably know roughly how it’s supposed to work. I confess, there are days when I feel the same way about computers. Long ago, during the renaissance of the computer age, it was possible to know everything about computers. But today, it is challenging to be fully knowledgeable even in one small area, and most people aren’t as savvy as they like to think. And, if I may borrow from Edwin Abbott Abbott’s classic Flatland, that includes me. And you. Need an example of what I mean? Take a look at almost any recent month’s batch of Windows updates. Just two quick questions for you: Do you need all of those updates? Is it safe to install all of those updates? I do software design and development for a living on Windows and the .NET platform, but I will be quite candid: I often have little clue what the heck some of those updates are going to do or why they are needed. So, if you do not know why they are needed or what they do, how do you know if they are safe? Of course, one can sidestep both questions by accepting Microsoft’s recommended Windows Update setting of “install updates automatically”. That leads you to infer that you need all of them (which is not always the case) and, more significantly, that they are safe. Quite safe. Ah, lest reality intrude upon such a pretty picture! Sadly, there is no such thing as risk-free software installation, and payloads from Windows Update are no exception. Earlier this year, a Windows Secrets Patch Watch article touted this headline: Keep this troublesome kernel update on hold. It discusses KB 2862330, a security update originally published more than 4 months earlier, and yet the article still recommends not installing it! Most people simply do not have the time, resources, or interest, to go about figuring out which updates to install or postpone or skip for safety reasons. Windows Secrets Patch Watch is the best service I have encountered for getting advice, but it is still no panacea and using the service effectively requires a degree of computer literacy that I still think is beyond a good number of people. Which brings us full circle: Step Away From That Computer! You’re Not Qualified to Use It!

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• Disable messages “Login failed for user” in Event log

  - by Michael Freidgeim

  I’ve noticed multiple messages in EventLog on my machineLogin failed for user 'NT AUTHORITY\ANONYMOUS LOGON'. Reason: Token-based server access validation failed with an infrastructure error. Check for previous errors. [CLIENT: 10.222.25.129]I’ve found that there are machines of my co-workers, but they were not sure, which processes tried to access my SQL server.I’ve tried a few things and finally in SQL Server Configuration Manager disabled tcp, as it was suggested inhttp://blogs.msdn.com/b/psssql/archive/2010/03/09/what-spn-do-i-use-and-how-does-it-get-there.aspx

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• List of Commonly Used Value Types in XNA Games

  - by Michael B. McLaughlin

  Most XNA programmers are concerned about generating garbage. More specifically about allocating GC-managed memory (GC stands for “garbage collector” and is both the name of the class that provides access to the garbage collector and an acronym for the garbage collector (as a concept) itself). Two of the major target platforms for XNA (Windows Phone 7 and Xbox 360) use variants of the .NET Compact Framework. On both variants, the GC runs under various circumstances (Windows Phone 7 and Xbox 360). Of concern to XNA programmers is the fact that it runs automatically after a fixed amount of GC-managed memory has been allocated (currently 1MB on both systems). Many beginning XNA programmers are unaware of what constitutes GC-managed memory, though. So here’s a quick overview. In .NET, there are two different “types” of types: value types and reference types. Only reference types are managed by the garbage collector. Value types are not managed by the garbage collector and are instead managed in other ways that are implementation dependent. For purposes of XNA programming, the important point is that they are not managed by the GC and thus do not, by themselves, increment that internal 1 MB allocation counter. (n.b. Structs are value types. If you have a struct that has a reference type as a member, then that reference type, when instantiated, will still be allocated in the GC-managed memory and will thus count against the 1 MB allocation counter. Putting it in a struct doesn’t change the fact that it gets allocated on the GC heap, but the struct itself is created outside of the GC’s purview). Both value types and reference types use the keyword ‘new’ to allocate a new instance of them. Sometimes this keyword is hidden by a method which creates new instances for you, e.g. XmlReader.Create. But the important thing to determine is whether or not you are dealing with a value types or a reference type. If it’s a value type, you can use the ‘new’ keyword to allocate new instances of that type without incrementing the GC allocation counter (except as above where it’s a struct with a reference type in it that is allocated by the constructor, but there are no .NET Framework or XNA Framework value types that do this so it would have to be a struct you created or that was in some third-party library you were using for that to even become an issue). The following is a list of most all of value types you are likely to use in a generic XNA game: AudioCategory (used with XACT; not available on WP7) AvatarExpression (Xbox 360 only, but exposed on Windows to ease Xbox development) bool BoundingBox BoundingSphere byte char Color DateTime decimal double any enum (System.Enum itself is a class, but all enums are value types such that there are no GC allocations for enums) float GamePadButtons GamePadCapabilities GamePadDPad GamePadState GamePadThumbSticks GamePadTriggers GestureSample int IntPtr (rarely but occasionally used in XNA) KeyboardState long Matrix MouseState nullable structs (anytime you see, e.g. int? something, that ‘?’ denotes a nullable struct, also called a nullable type) Plane Point Quaternion Ray Rectangle RenderTargetBinding sbyte (though I’ve never seen it used since most people would just use a short) short TimeSpan TouchCollection TouchLocation TouchPanelCapabilities uint ulong ushort Vector2 Vector3 Vector4 VertexBufferBinding VertexElement VertexPositionColor VertexPositionColorTexture VertexPositionNormalTexture VertexPositionTexture Viewport So there you have it. That’s not quite a complete list, mind you. For example: There are various structs in the .NET framework you might make use of. I left out everything from the Microsoft.Xna.Framework.Graphics.PackedVector namespace, since everything in there ventures into the realm of advanced XNA programming anyway (n.b. every single instantiable thing in that namespace is a struct and thus a value type; there are also two interfaces but interfaces cannot be instantiated at all and thus don’t figure in to this discussion). There are so many enums you’re likely to use (PlayerIndex, SpriteSortMode, SpriteEffects, SurfaceFormat, etc.) that including them would’ve flooded the list and reduced its utility. So I went with “any enum” and trust that you can figure out what the enums are (and it’s rare to use ‘new’ with an enum anyway). That list also doesn’t include any of the pre-defined static instances of some of the classes (e.g. BlendState.AlphaBlend, BlendState.Opaque, etc.) which are already allocated such that using them doesn’t cause any new allocations and therefore doesn’t increase that 1 MB counter. That list also has a few misleading things. VertexElement, VertexPositionColor, and all the other vertex types are structs. But you’re only likely to ever use them as an array (for use with VertexBuffer or DynamicVertexBuffer), and all arrays are reference types (even arrays of value types such as VertexPositionColor[ ] or int[ ]). * So that’s it for now. The note below may be a bit confusing (it deals with how the GC works and how arrays are managed in .NET). If so, you can probably safely ignore it for now but feel free to ask any questions regardless. * Arrays of value types (where the value type doesn’t contain any reference type members) are much faster for the GC to examine than arrays of reference types, so there is a definite benefit to using arrays of value types where it makes sense. But creating arrays of value types does cause the GC’s allocation counter to increase. Indeed, allocating a large array of a value type is one of the quickest ways to increment the allocation counter since a .NET array is a sequential block of memory. An array of reference types is just a sequential block of references (typically 4 bytes each) while an array of value types is a sequential block of instances of that type. So for an array of Vector3s it would be 12 bytes each since each float is 4 bytes and there are 3 in a Vector3; for an array of VertexPositionNormalTexture structs it would typically be 32 bytes each since it has two Vector3s and a Vector2. (Note that there are a few additional bytes taken up in the creation of an array, typically 12 but sometimes 16 or possibly even more, which depend on the implementation details of the array type on the particular platform the code is running on).

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• Can I use Ubuntu One to sync data fiies between two remote computers

  - by Sleepy John

  I've got two computers, both running Ubuntu with files in their home folders sync'd in to Ubuntu One. I'd like to know if it's possible to make Ubuntu One automatically download data changes that have been uploaded automatically to Ubuntu One from one computer to the equivalent data file in the other. Clarifying a bit further, I've installed Red Notebook in both computers and so they each have their own /.rednotebook/data folder containing a series of .txt files corresponding to the monthly entries in each of them. These are sync'd to upload any changes to those .txt files to Ubuntu One. My question is can I, and if so how, do I make Ubuntu One automatically download and replace those .txt files in the other computer after they've been updated and uploaded from the first computer? I did labouriously manage to download all those text files which had been uploaded from the first computer, from Ubuntu One one-by-one to the second computer, but what I want to do is automate this process and that's where I'm stuck. I'm aware that things could get a bit complicated if both my computers were on-line at the same time and both were simultaneously making different Red Notebook entries, so that's not the scenario I'm trying to cover. All I want to achieve is that whatever updates to the files have been uploaded by one computer, will automatically be downloaded to the same-named files in the other computer as soon as that second computer appears on line and detects that Ubuntu One has matching but more recent sync'd files than the ones it's holding.

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• C#/.NET &ndash; Finding an Item&rsquo;s Index in IEnumerable&lt;T&gt;

  - by James Michael Hare

  Sorry for the long blogging hiatus.  First it was, of course, the holidays hustle and bustle, then my brother and his wife gave birth to their son, so I’ve been away from my blogging for two weeks. Background: Finding an item’s index in List<T> is easy… Many times in our day to day programming activities, we want to find the index of an item in a collection.  Now, if we have a List<T> and we’re looking for the item itself this is trivial: 1: // assume have a list of ints: 2: var list = new List<int> { 1, 13, 42, 64, 121, 77, 5, 99, 132 }; 3:  4: // can find the exact item using IndexOf() 5: var pos = list.IndexOf(64); This will return the position of the item if it’s found, or –1 if not.  It’s easy to see how this works for primitive types where equality is well defined.  For complex types, however, it will attempt to compare them using EqualityComparer<T>.Default which, in a nutshell, relies on the object’s Equals() method. So what if we want to search for a condition instead of equality?  That’s also easy in a List<T> with the FindIndex() method: 1: // assume have a list of ints: 2: var list = new List<int> { 1, 13, 42, 64, 121, 77, 5, 99, 132 }; 3:  4: // finds index of first even number or -1 if not found. 5: var pos = list.FindIndex(i => i % 2 == 0);   Problem: Finding an item’s index in IEnumerable<T> is not so easy... This is all well and good for lists, but what if we want to do the same thing for IEnumerable<T>?  A collection of IEnumerable<T> has no indexing, so there’s no direct method to find an item’s index.  LINQ, as powerful as it is, gives us many tools to get us this information, but not in one step.  As with almost any problem involving collections, there are several ways to accomplish the same goal.  And once again as with almost any problem involving collections, the choice of the solution somewhat depends on the situation. So let’s look at a few possible alternatives.  I’m going to express each of these as extension methods for simplicity and consistency. Solution: The TakeWhile() and Count() combo One of the things you can do is to perform a TakeWhile() on the list as long as your find condition is not true, and then do a Count() of the items it took.  The only downside to this method is that if the item is not in the list, the index will be the full Count() of items, and not –1.  So if you don’t know the size of the list beforehand, this can be confusing. 1: // a collection of extra extension methods off IEnumerable<T> 2: public static class EnumerableExtensions 3: { 4: // Finds an item in the collection, similar to List<T>.FindIndex() 5: public static int FindIndex<T>(this IEnumerable<T> list, Predicate<T> finder) 6: { 7: // note if item not found, result is length and not -1! 8: return list.TakeWhile(i => !finder(i)).Count(); 9: } 10: } Personally, I don’t like switching the paradigm of not found away from –1, so this is one of my least favorites.  Solution: Select with index Many people don’t realize that there is an alternative form of the LINQ Select() method that will provide you an index of the item being selected: 1: list.Select( (item,index) => do something here with the item and/or index... ) This can come in handy, but must be treated with care.  This is because the index provided is only as pertains to the result of previous operations (if any).  For example: 1: // assume have a list of ints: 2: var list = new List<int> { 1, 13, 42, 64, 121, 77, 5, 99, 132 }; 3:  4: // you'd hope this would give you the indexes of the even numbers 5: // which would be 2, 3, 8, but in reality it gives you 0, 1, 2 6: list.Where(item => item % 2 == 0).Select((item,index) => index); The reason the example gives you the collection { 0, 1, 2 } is because the where clause passes over any items that are odd, and therefore only the even items are given to the select and only they are given indexes. Conversely, we can’t select the index and then test the item in a Where() clause, because then the Where() clause would be operating on the index and not the item! So, what we have to do is to select the item and index and put them together in an anonymous type.  It looks ugly, but it works: 1: // extensions defined on IEnumerable<T> 2: public static class EnumerableExtensions 3: { 4: // finds an item in a collection, similar to List<T>.FindIndex() 5: public static int FindIndex<T>(this IEnumerable<T> list, Predicate<T> finder) 6: { 7: // if you don't name the anonymous properties they are the variable names 8: return list.Select((item, index) => new { item, index }) 9: .Where(p => finder(p.item)) 10: .Select(p => p.index + 1) 11: .FirstOrDefault() - 1; 12: } 13: }     So let’s look at this, because i know it’s convoluted: First Select() joins the items and their indexes into an anonymous type. Where() filters that list to only the ones matching the predicate. Second Select() picks the index of the matches and adds 1 – this is to distinguish between not found and first item. FirstOrDefault() returns the first item found from the previous clauses or default (zero) if not found. Subtract one so that not found (zero) will be –1, and first item (one) will be zero. The bad thing is, this is ugly as hell and creates anonymous objects for each item tested until it finds the match.  This concerns me a bit but we’ll defer judgment until compare the relative performances below. Solution: Convert ToList() and use FindIndex() This solution is easy enough.  We know any IEnumerable<T> can be converted to List<T> using the LINQ extension method ToList(), so we can easily convert the collection to a list and then just use the FindIndex() method baked into List<T>. 1: // a collection of extension methods for IEnumerable<T> 2: public static class EnumerableExtensions 3: { 4: // find the index of an item in the collection similar to List<T>.FindIndex() 5: public static int FindIndex<T>(this IEnumerable<T> list, Predicate<T> finder) 6: { 7: return list.ToList().FindIndex(finder); 8: } 9: } This solution is simplicity itself!  It is very concise and elegant and you need not worry about anyone misinterpreting what it’s trying to do (as opposed to the more convoluted LINQ methods above). But the main thing I’m concerned about here is the performance hit to allocate the List<T> in the ToList() call, but once again we’ll explore that in a second. Solution: Roll your own FindIndex() for IEnumerable<T> Of course, you can always roll your own FindIndex() method for IEnumerable<T>.  It would be a very simple for loop which scans for the item and counts as it goes.  There’s many ways to do this, but one such way might look like: 1: // extension methods for IEnumerable<T> 2: public static class EnumerableExtensions 3: { 4: // Finds an item matching a predicate in the enumeration, much like List<T>.FindIndex() 5: public static int FindIndex<T>(this IEnumerable<T> list, Predicate<T> finder) 6: { 7: int index = 0; 8: foreach (var item in list) 9: { 10: if (finder(item)) 11: { 12: return index; 13: } 14:  15: index++; 16: } 17:  18: return -1; 19: } 20: } Well, it’s not quite simplicity, and those less familiar with LINQ may prefer it since it doesn’t include all of the lambdas and behind the scenes iterators that come with deferred execution.  But does having this long, blown out method really gain us much in performance? Comparison of Proposed Solutions So we’ve now seen four solutions, let’s analyze their collective performance.  I took each of the four methods described above and run them over 100,000 iterations of lists of size 10, 100, 1000, and 10000 and here’s the performance results.  Then I looked for targets at the begining of the list (best case), middle of the list (the average case) and not in the list (worst case as must scan all of the list). Each of the times below is the average time in milliseconds for one execution as computer over the 100,000 iterations: Searches Matching First Item (Best Case)   10 100 1000 10000 TakeWhile 0.0003 0.0003 0.0003 0.0003 Select 0.0005 0.0005 0.0005 0.0005 ToList 0.0002 0.0003 0.0013 0.0121 Manual 0.0001 0.0001 0.0001 0.0001   Searches Matching Middle Item (Average Case)   10 100 1000 10000 TakeWhile 0.0004 0.0020 0.0191 0.1889 Select 0.0008 0.0042 0.0387 0.3802 ToList 0.0002 0.0007 0.0057 0.0562 Manual 0.0002 0.0013 0.0129 0.1255   Searches Where Not Found (Worst Case)   10 100 1000 10000 TakeWhile 0.0006 0.0039 0.0381 0.3770 Select 0.0012 0.0081 0.0758 0.7583 ToList 0.0002 0.0012 0.0100 0.0996 Manual 0.0003 0.0026 0.0253 0.2514   Notice something interesting here, you’d think the “roll your own” loop would be the most efficient, but it only wins when the item is first (or very close to it) regardless of list size.  In almost all other cases though and in particular the average case and worst case, the ToList()/FindIndex() combo wins for performance, even though it is creating some temporary memory to hold the List<T>.  If you examine the algorithm, the reason why is most likely because once it’s in a ToList() form, internally FindIndex() scans the internal array which is much more efficient to iterate over.  Thus, it takes a one time performance hit (not including any GC impact) to create the List<T> but after that the performance is much better. Summary If you’re concerned about too many throw-away objects, you can always roll your own FindIndex() method, but for sheer simplicity and overall performance, using the ToList()/FindIndex() combo performs best on nearly all list sizes in the average and worst cases.    Technorati Tags: C#,.NET,Litte Wonders,BlackRabbitCoder,Software,LINQ,List

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• Digital Darwinism: How Brands Can Survive the Rapid Evolution of Society and Technology

  - by Michael Hylton

  Do you want to learn how to thrive in an era of connected consumerism and digital disruptions? Come attend this free webinar on December 13th at 10:00 am PST / 1:00 pm EST as Brian Solis, Altimeter Group analyst, shares his thoughts on how our changing society and technology shifts are impacting brands today. Click here to register for this webcast, part of Oracle’s Social Business Thought Leaders Series.

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• No endpoint listening at.........

  - by Michael Stephenson

  I was having some very frustrating behaviour on our build server and while I found a number of articles online with similar error messages none of them helped me.  I thought I would just explain this here incase if helps me or anyone else in future.The error message we were getting is:There was no endpoint listening at http://localhostStubs.ExternalApplication/SampleService.svc that could accept the message. This is often caused by an incorrect address or SOAP action. See InnerException, if present, for more detailsOur scenario is as follows:We have a solution where a WCF service application hosting the WCF routing service is listening to the Windows Azure Service Bus Relay.  We have an acceptance test project in the solution which sends a message to the service bus which is then received by the WCF routing service and routed to SampleService.svc which is hosted in another IIS application on the same box.  A response is flowed back through to the test.  In the tests there are 5 scenarios simulating a successful message, and various error conditions.  On my developer machine it was working absolutely fine every time, and a clean build on my developer machine worked fine.  On the build server however one or more of the tests would fail each time with the above error message.  There didnt seem to be any pattern to which test would fail.The solution was building on a Windows 2008 R2 machine with IIS 7 and AppFabric Server installed with auto-start configured for the IIS Application which would be listening to service bus.After lots of searching online and looking at logs etc it turned out to be a simple solution to just restart the WAS service (Windows Process Activation Service) and the services it advised you to restart with it.  Hope this helps someone else

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• First steps into css - aligning data insite one DIV [on hold]

  - by Andrew

  I am trying to move away from tables, and start doing CSS. Here is my HTML code that I currently trying to place into a nice looking container. <div> <div> <h2>ID: 4000 | SSN#: 4545</h2> </div> <div> <img src="./images/tenant/unknown.png"> </div> <div> <h3>Names Used</h3> Will Smith<br> Bill Smmith<br> John Smith<br> Will Smith<br> Bill Smmith<br> John Smith<br> Will Smith<br> Bill Smmith<br> John Smith<br> </div> <div> <h3>Phones Used</h3> 123456789<br> 123456789<br> 123456789<br> 123456789<br> 123456789<br> 123456789<br> 123456789<br> 123456789<br> </div> <div> <h3>Addresses Used</h3> 125 Main Evanston IL 60202<br> 465 Greenwood St. Schaumburg null 60108<br> 125 Main Evanston IL 60202<br> 465 Greenwood St. Schaumburg null 60108<br> 125 Main Evanston IL 60202<br> 465 Greenwood St. Schaumburg null 60108<br> 125 Main Evanston IL 60202<br> 465 Greenwood St. Schaumburg null 60108<br> 125 Main Evanston IL 60202<br> 465 Greenwood St. Schaumburg null 60108<br> </div> </div> I now understand now I create classes and assign classes to elements. I have no issues doing colors. But I am very confused with elements alignments. Could you suggest a nice way to pack it together with some CSS which I can analyze and take as a CSS starting learning point?

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• Troubleshooting Microsoft Message Queuing Issues on Microsoft Lync Server 2010

  - by John Breakwell

  This blog post sounds specific but most of the troubleshooting tips can be applied to other scenarios: Troubleshooting Microsoft Message Queuing Issues on Microsoft Lync Server 2010 Microsoft Message Queuing (MSMQ) plays an important role in the Microsoft Lync Server 2010 Monitoring/Archiving server infrastructure: in a distributed network environment, MSMQ is used to transmit data from agents located on other servers (such as Front End Servers) to Monitoring/Archiving servers. The purpose of this article is to help you discover the root cause of any MSMQ problems that you might encounter, and to provide suggested ways to fix those problems. Microsoft Lync Server is the new name for Microsoft Office Communications Server. It’s good to see a major product make use of MSMQ – there aren’t many in the public eye (Symantec’s Enterprise Vault comes to mind).

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• Idea to develop a caching server between IIS and SQL Server

  - by John

  I work on a few high traffic websites that all share the same database and that are all heavily database driven. Our SQL server is max-ed out and, although we have already implemented many changes that have helped but the server is still working too hard. We employ some caching in our website but the type of queries we use negate using SQL dependency caching. We tried SQL replication to try and kind of load balance but that didn't prove very successful because the replication process is quite demanding on the servers too and it needed to be done frequently as it is important that data is up to date. We do use a Varnish web caching server (Linux based) to take a bit of the load off both the web and database server but as a lot of the sites are customised based on the user we can only do so much. Anyway, the reason for this question... Varnish gave me an idea for a possible application that might help in this situation. Just like Varnish sits between a web browser and the web server and caches response from the web server, I was wondering about the possibility of creating something that sits between the web server and the database server. Imagine that all SQL queries go through this SQL caching server. If it's a first time query then it will get recorded, and the result requested from the SQL server and stored locally on the cache server. If it's a repeat request within a set time then the result gets retrieved from the local copy without the query being sent to the SQL server. The caching server could also take advantage of SQL dependency caching notifications. This seems like a good idea in theory. There's still the same amount of data moving back and forward from the web server, but the SQL server is relieved of the work of processing the repeat queries. I wonder about how difficult it would be to build a service that sort of emulates requests and responses from SQL server, whether SQL server's own caching is doing enough of this already that this wouldn't be a benefit, or even if someone has done this before and I haven't found it? I would welcome any feedback or any references to any relevant projects.

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• Of C# Iterators and Performance

  - by James Michael Hare

  Some of you reading this will be wondering, "what is an iterator" and think I'm locked in the world of C++.  Nope, I'm talking C# iterators.  No, not enumerators, iterators.   So, for those of you who do not know what iterators are in C#, I will explain it in summary, and for those of you who know what iterators are but are curious of the performance impacts, I will explore that as well.   Iterators have been around for a bit now, and there are still a bunch of people who don't know what they are or what they do.  I don't know how many times at work I've had a code review on my code and have someone ask me, "what's that yield word do?"   Basically, this post came to me as I was writing some extension methods to extend IEnumerable<T> -- I'll post some of the fun ones in a later post.  Since I was filtering the resulting list down, I was using the standard C# iterator concept; but that got me wondering: what are the performance implications of using an iterator versus returning a new enumeration?   So, to begin, let's look at a couple of methods.  This is a new (albeit contrived) method called Every(...).  The goal of this method is to access and enumeration and return every nth item in the enumeration (including the first).  So Every(2) would return items 0, 2, 4, 6, etc.   Now, if you wanted to write this in the traditional way, you may come up with something like this:       public static IEnumerable<T> Every<T>(this IEnumerable<T> list, int interval)     {         List<T> newList = new List<T>();         int count = 0;           foreach (var i in list)         {             if ((count++ % interval) == 0)             {                 newList.Add(i);             }         }           return newList;     }     So basically this method takes any IEnumerable<T> and returns a new IEnumerable<T> that contains every nth item.  Pretty straight forward.   The problem?  Well, Every<T>(...) will construct a list containing every nth item whether or not you care.  What happens if you were searching this result for a certain item and find that item after five tries?  You would have generated the rest of the list for nothing.   Enter iterators.  This C# construct uses the yield keyword to effectively defer evaluation of the next item until it is asked for.  This can be very handy if the evaluation itself is expensive or if there's a fair chance you'll never want to fully evaluate a list.   We see this all the time in Linq, where many expressions are chained together to do complex processing on a list.  This would be very expensive if each of these expressions evaluated their entire possible result set on call.    Let's look at the same example function, this time using an iterator:       public static IEnumerable<T> Every<T>(this IEnumerable<T> list, int interval)     {         int count = 0;         foreach (var i in list)         {             if ((count++ % interval) == 0)             {                 yield return i;             }         }     }   Notice it does not create a new return value explicitly, the only evidence of a return is the "yield return" statement.  What this means is that when an item is requested from the enumeration, it will enter this method and evaluate until it either hits a yield return (in which case that item is returned) or until it exits the method or hits a yield break (in which case the iteration ends.   Behind the scenes, this is all done with a class that the CLR creates behind the scenes that keeps track of the state of the iteration, so that every time the next item is asked for, it finds that item and then updates the current position so it knows where to start at next time.   It doesn't seem like a big deal, does it?  But keep in mind the key point here: it only returns items as they are requested. Thus if there's a good chance you will only process a portion of the return list and/or if the evaluation of each item is expensive, an iterator may be of benefit.   This is especially true if you intend your methods to be chainable similar to the way Linq methods can be chained.    For example, perhaps you have a List<int> and you want to take every tenth one until you find one greater than 10.  We could write that as:       List<int> someList = new List<int>();         // fill list here         someList.Every(10).TakeWhile(i => i <= 10);     Now is the difference more apparent?  If we use the first form of Every that makes a copy of the list.  It's going to copy the entire list whether we will need those items or not, that can be costly!    With the iterator version, however, it will only take items from the list until it finds one that is > 10, at which point no further items in the list are evaluated.   So, sounds neat eh?  But what's the cost is what you're probably wondering.  So I ran some tests using the two forms of Every above on lists varying from 5 to 500,000 integers and tried various things.    Now, iteration isn't free.  If you are more likely than not to iterate the entire collection every time, iterator has some very slight overhead:   Copy vs Iterator on 100% of Collection (10,000 iterations) Collection Size Num Iterated Type Total ms 5 5 Copy 5 5 5 Iterator 5 50 50 Copy 28 50 50 Iterator 27 500 500 Copy 227 500 500 Iterator 247 5000 5000 Copy 2266 5000 5000 Iterator 2444 50,000 50,000 Copy 24,443 50,000 50,000 Iterator 24,719 500,000 500,000 Copy 250,024 500,000 500,000 Iterator 251,521   Notice that when iterating over the entire produced list, the times for the iterator are a little better for smaller lists, then getting just a slight bit worse for larger lists.  In reality, given the number of items and iterations, the result is near negligible, but just to show that iterators come at a price.  However, it should also be noted that the form of Every that returns a copy will have a left-over collection to garbage collect.   However, if we only partially evaluate less and less through the list, the savings start to show and make it well worth the overhead.  Let's look at what happens if you stop looking after 80% of the list:   Copy vs Iterator on 80% of Collection (10,000 iterations) Collection Size Num Iterated Type Total ms 5 4 Copy 5 5 4 Iterator 5 50 40 Copy 27 50 40 Iterator 23 500 400 Copy 215 500 400 Iterator 200 5000 4000 Copy 2099 5000 4000 Iterator 1962 50,000 40,000 Copy 22,385 50,000 40,000 Iterator 19,599 500,000 400,000 Copy 236,427 500,000 400,000 Iterator 196,010       Notice that the iterator form is now operating quite a bit faster.  But the savings really add up if you stop on average at 50% (which most searches would typically do):     Copy vs Iterator on 50% of Collection (10,000 iterations) Collection Size Num Iterated Type Total ms 5 2 Copy 5 5 2 Iterator 4 50 25 Copy 25 50 25 Iterator 16 500 250 Copy 188 500 250 Iterator 126 5000 2500 Copy 1854 5000 2500 Iterator 1226 50,000 25,000 Copy 19,839 50,000 25,000 Iterator 12,233 500,000 250,000 Copy 208,667 500,000 250,000 Iterator 122,336   Now we see that if we only expect to go on average 50% into the results, we tend to shave off around 40% of the time.  And this is only for one level deep.  If we are using this in a chain of query expressions it only adds to the savings.   So my recommendation?  If you have a resonable expectation that someone may only want to partially consume your enumerable result, I would always tend to favor an iterator.  The cost if they iterate the whole thing does not add much at all -- and if they consume only partially, you reap some really good performance gains.   Next time I'll discuss some of my favorite extensions I've created to make development life a little easier and maintainability a little better.

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• ANTS Memory Profiler 7.0 Review

  - by Michael B. McLaughlin

  (This is my first review as a part of the GeeksWithBlogs.net Influencers program. It’s a program in which I (and the others who have been selected for it) get the opportunity to check out new products and services and write reviews about them. We don’t get paid for this, but we do generally get to keep a copy of the software or retain an account for some period of time on the service that we review. In this case I received a copy of Red Gate Software’s ANTS Memory Profiler 7.0, which was released in January. I don’t have any upgrade rights nor is my review guided, restrained, influenced, or otherwise controlled by Red Gate or anyone else. But I do get to keep the software license. I will always be clear about what I received whenever I do a review – I leave it up to you to decide whether you believe I can be objective. I believe I can be. If I used something and really didn’t like it, keeping a copy of it wouldn’t be worth anything to me. In that case though, I would simply uninstall/deactivate/whatever the software or service and tell the company what I didn’t like about it so they could (hopefully) make it better in the future. I don’t think it’d be polite to write up a terrible review, nor do I think it would be a particularly good use of my time. There are people who get paid for a living to review things, so I leave it to them to tell you what they think is bad and why. I’ll only spend my time telling you about things I think are good.) Overview of Common .NET Memory Problems When coming to land of managed memory from the wilds of unmanaged code, it’s easy to say to one’s self, “Wow! Now I never have to worry about memory problems again!” But this simply isn’t true. Managed code environments, such as .NET, make many, many things easier. You will never have to worry about memory corruption due to a bad pointer, for example (unless you’re working with unsafe code, of course). But managed code has its own set of memory concerns. For example, failing to unsubscribe from events when you are done with them leaves the publisher of an event with a reference to the subscriber. If you eliminate all your own references to the subscriber, then that memory is effectively lost since the GC won’t delete it because of the publishing object’s reference. When the publishing object itself becomes subject to garbage collection then you’ll get that memory back finally, but that could take a very long time depending of the life of the publisher. Another common source of resource leaks is failing to properly release unmanaged resources. When writing a class that contains members that hold unmanaged resources (e.g. any of the Stream-derived classes, IsolatedStorageFile, most classes ending in “Reader” or “Writer”), you should always implement IDisposable, making sure to use a properly written Dispose method. And when you are using an instance of a class that implements IDisposable, you should always make sure to use a 'using' statement in order to ensure that the object’s unmanaged resources are disposed of properly. (A ‘using’ statement is a nicer, cleaner looking, and easier to use version of a try-finally block. The compiler actually translates it as though it were a try-finally block. Note that Code Analysis warning 2202 (CA2202) will often be triggered by nested using blocks. A properly written dispose method ensures that it only runs once such that calling dispose multiple times should not be a problem. Nonetheless, CA2202 exists and if you want to avoid triggering it then you should write your code such that only the innermost IDisposable object uses a ‘using’ statement, with any outer code making use of appropriate try-finally blocks instead). Then, of course, there are situations where you are operating in a memory-constrained environment or else you want to limit or even eliminate allocations within a certain part of your program (e.g. within the main game loop of an XNA game) in order to avoid having the GC run. On the Xbox 360 and Windows Phone 7, for example, for every 1 MB of heap allocations you make, the GC runs; the added time of a GC collection can cause a game to drop frames or run slowly thereby making it look bad. Eliminating allocations (or else minimizing them and calling an explicit Collect at an appropriate time) is a common way of avoiding this (the other way is to simplify your heap so that the GC’s latency is low enough not to cause performance issues). ANTS Memory Profiler 7.0 When the opportunity to review Red Gate’s recently released ANTS Memory Profiler 7.0 arose, I jumped at it. In order to review it, I was given a free copy (which does not include upgrade rights for future versions) which I am allowed to keep. For those of you who are familiar with ANTS Memory Profiler, you can find a list of new features and enhancements here. If you are an experienced .NET developer who is familiar with .NET memory management issues, ANTS Memory Profiler is great. More importantly still, if you are new to .NET development or you have no experience or limited experience with memory profiling, ANTS Memory Profiler is awesome. From the very beginning, it guides you through the process of memory profiling. If you’re experienced and just want dive in however, it doesn’t get in your way. The help items GAHSFLASHDAJLDJA are well designed and located right next to the UI controls so that they are easy to find without being intrusive. When you first launch it, it presents you with a “Getting Started” screen that contains links to “Memory profiling video tutorials”, “Strategies for memory profiling”, and the “ANTS Memory Profiler forum”. I’m normally the kind of person who looks at a screen like that only to find the “Don’t show this again” checkbox. Since I was doing a review, though, I decided I should examine them. I was pleasantly surprised. The overview video clocks in at three minutes and fifty seconds. It begins by showing you how to get started profiling an application. It explains that profiling is done by taking memory snapshots periodically while your program is running and then comparing them. ANTS Memory Profiler (I’m just going to call it “ANTS MP” from here) analyzes these snapshots in the background while your application is running. It briefly mentions a new feature in Version 7, a new API that give you the ability to trigger snapshots from within your application’s source code (more about this below). You can also, and this is the more common way you would do it, take a memory snapshot at any time from within the ANTS MP window by clicking the “Take Memory Snapshot” button in the upper right corner. The overview video goes on to demonstrate a basic profiling session on an application that pulls information from a database and displays it. It shows how to switch which snapshots you are comparing, explains the different sections of the Summary view and what they are showing, and proceeds to show you how to investigate memory problems using the “Instance Categorizer” to track the path from an object (or set of objects) to the GC’s root in order to find what things along the path are holding a reference to it/them. For a set of objects, you can then click on it and get the “Instance List” view. This displays all of the individual objects (including their individual sizes, values, etc.) of that type which share the same path to the GC root. You can then click on one of the objects to generate an “Instance Retention Graph” view. This lets you track directly up to see the reference chain for that individual object. In the overview video, it turned out that there was an event handler which was holding on to a reference, thereby keeping a large number of strings that should have been freed in memory. Lastly the video shows the “Class List” view, which lets you dig in deeply to find problems that might not have been clear when following the previous workflow. Once you have at least one memory snapshot you can begin analyzing. The main interface is in the “Analysis” tab. You can also switch to the “Session Overview” tab, which gives you several bar charts highlighting basic memory data about the snapshots you’ve taken. If you hover over the individual bars (and the individual colors in bars that have more than one), you will see a detailed text description of what the bar is representing visually. The Session Overview is good for a quick summary of memory usage and information about the different heaps. You are going to spend most of your time in the Analysis tab, but it’s good to remember that the Session Overview is there to give you some quick feedback on basic memory usage stats. As described above in the summary of the overview video, there is a certain natural workflow to the Analysis tab. You’ll spin up your application and take some snapshots at various times such as before and after clicking a button to open a window or before and after closing a window. Taking these snapshots lets you examine what is happening with memory. You would normally expect that a lot of memory would be freed up when closing a window or exiting a document. By taking snapshots before and after performing an action like that you can see whether or not the memory is really being freed. If you already know an area that’s giving you trouble, you can run your application just like normal until just before getting to that part and then you can take a few strategic snapshots that should help you pin down the problem. Something the overview didn’t go into is how to use the “Filters” section at the bottom of ANTS MP together with the Class List view in order to narrow things down. The video tutorials page has a nice 3 minute intro video called “How to use the filters”. It’s a nice introduction and covers some of the basics. I’m going to cover a bit more because I think they’re a really neat, really helpful feature. Large programs can bring up thousands of classes. Even simple programs can instantiate far more classes than you might realize. In a basic .NET 4 WPF application for example (and when I say basic, I mean just MainWindow.xaml with a button added to it), the unfiltered Class List view will have in excess of 1000 classes (my simple test app had anywhere from 1066 to 1148 classes depending on which snapshot I was using as the “Current” snapshot). This is amazing in some ways as it shows you how in stark detail just how immensely powerful the WPF framework is. But hunting through 1100 classes isn’t productive, no matter how cool it is that there are that many classes instantiated and doing all sorts of awesome things. Let’s say you wanted to examine just the classes your application contains source code for (in my simple example, that would be the MainWindow and App). Under “Basic Filters”, click on “Classes with source” under “Show only…”. Voilà. Down from 1070 classes in the snapshot I was using as “Current” to 2 classes. If you then click on a class’s name, it will show you (to the right of the class name) two little icon buttons. Hover over them and you will see that you can click one to view the Instance Categorizer for the class and another to view the Instance List for the class. You can also show classes based on which heap they live on. If you chose both a Baseline snapshot and a Current snapshot then you can use the “Comparing snapshots” filters to show only: “New objects”; “Surviving objects”; “Survivors in growing classes”; or “Zombie objects” (if you aren’t sure what one of these means, you can click the helpful “?” in a green circle icon to bring up a popup that explains them and provides context). Remember that your selection(s) under the “Show only…” heading will still apply, so you should update those selections to make sure you are seeing the view you want. There are also links under the “What is my memory problem?” heading that can help you diagnose the problems you are seeing including one for “I don’t know which kind I have” for situations where you know generally that your application has some problems but aren’t sure what the behavior you have been seeing (OutOfMemoryExceptions, continually growing memory usage, larger memory use than expected at certain points in the program). The Basic Filters are not the only filters there are. “Filter by Object Type” gives you the ability to filter by: “Objects that are disposable”; “Objects that are/are not disposed”; “Objects that are/are not GC roots” (GC roots are things like static variables); and “Objects that implement _______”. “Objects that implement” is particularly neat. Once you check the box, you can then add one or more classes and interfaces that an object must implement in order to survive the filtering. Lastly there is “Filter by Reference”, which gives you the option to pare down the list based on whether an object is “Kept in memory exclusively by” a particular item, a class/interface, or a namespace; whether an object is “Referenced by” one or more of those choices; and whether an object is “Never referenced by” one or more of those choices. Remember that filtering is cumulative, so anything you had set in one of the filter sections still remains in effect unless and until you go back and change it. There’s quite a bit more to ANTS MP – it’s a very full featured product – but I think I touched on all of the most significant pieces. You can use it to debug: a .NET executable; an ASP.NET web application (running on IIS); an ASP.NET web application (running on Visual Studio’s built-in web development server); a Silverlight 4 browser application; a Windows service; a COM+ server; and even something called an XBAP (local XAML browser application). You can also attach to a .NET 4 process to profile an application that’s already running. The startup screen also has a large number of “Charting Options” that let you adjust which statistics ANTS MP should collect. The default selection is a good, minimal set. It’s worth your time to browse through the charting options to examine other statistics that may also help you diagnose a particular problem. The more statistics ANTS MP collects, the longer it will take to collect statistics. So just turning everything on is probably a bad idea. But the option to selectively add in additional performance counters from the extensive list could be a very helpful thing for your memory profiling as it lets you see additional data that might provide clues about a particular problem that has been bothering you. ANTS MP integrates very nicely with all versions of Visual Studio that support plugins (i.e. all of the non-Express versions). Just note that if you choose “Profile Memory” from the “ANTS” menu that it will launch profiling for whichever project you have set as the Startup project. One quick tip from my experience so far using ANTS MP: if you want to properly understand your memory usage in an application you’ve written, first create an “empty” version of the type of project you are going to profile (a WPF application, an XNA game, etc.) and do a quick profiling session on that so that you know the baseline memory usage of the framework itself. By “empty” I mean just create a new project of that type in Visual Studio then compile it and run it with profiling – don’t do anything special or add in anything (except perhaps for any external libraries you’re planning to use). The first thing I tried ANTS MP out on was a demo XNA project of an editor that I’ve been working on for quite some time that involves a custom extension to XNA’s content pipeline. The first time I ran it and saw the unmanaged memory usage I was convinced I had some horrible bug that was creating extra copies of texture data (the demo project didn’t have a lot of texture data so when I saw a lot of unmanaged memory I instantly figured I was doing something wrong). Then I thought to run an empty project through and when I saw that the amount of unmanaged memory was virtually identical, it dawned on me that the CLR itself sits in unmanaged memory and that (thankfully) there was nothing wrong with my code! Quite a relief. Earlier, when discussing the overview video, I mentioned the API that lets you take snapshots from within your application. I gave it a quick trial and it’s very easy to integrate and make use of and is a really nice addition (especially for projects where you want to know what, if any, allocations there are in a specific, complicated section of code). The only concern I had was that if I hadn’t watched the overview video I might never have known it existed. Even then it took me five minutes of hunting around Red Gate’s website before I found the “Taking snapshots from your code" article that explains what DLL you need to add as a reference and what method of what class you should call in order to take an automatic snapshot (including the helpful warning to wrap it in a try-catch block since, under certain circumstances, it can raise an exception, such as trying to call it more than 5 times in 30 seconds. The difficulty in discovering and then finding information about the automatic snapshots API was one thing I thought could use improvement. Another thing I think would make it even better would be local copies of the webpages it links to. Although I’m generally always connected to the internet, I imagine there are more than a few developers who aren’t or who are behind very restrictive firewalls. For them (and for me, too, if my internet connection happens to be down), it would be nice to have those documents installed locally or to have the option to download an additional “documentation” package that would add local copies. Another thing that I wish could be easier to manage is the Filters area. Finding and setting individual filters is very easy as is understanding what those filter do. And breaking it up into three sections (basic, by object, and by reference) makes sense. But I could easily see myself running a long profiling session and forgetting that I had set some filter a long while earlier in a different filter section and then spending quite a bit of time trying to figure out why some problem that was clearly visible in the data wasn’t showing up in, e.g. the instance list before remembering to check all the filters for that one setting that was only culling a few things from view. Some sort of indicator icon next to the filter section names that appears you have at least one filter set in that area would be a nice visual clue to remind me that “oh yeah, I told it to only show objects on the Gen 2 heap! That’s why I’m not seeing those instances of the SuperMagic class!” Something that would be nice (but that Red Gate cannot really do anything about) would be if this could be used in Windows Phone 7 development. If Microsoft and Red Gate could work together to make this happen (even if just on the WP7 emulator), that would be amazing. Especially given the memory constraints that apps and games running on mobile devices need to work within, a good memory profiler would be a phenomenally helpful tool. If anyone at Microsoft reads this, it’d be really great if you could make something like that happen. Perhaps even a (subsidized) custom version just for WP7 development. (For XNA games, of course, you can create a Windows version of the game and use ANTS MP on the Windows version in order to get a better picture of your memory situation. For Silverlight on WP7, though, there’s quite a bit of educated guess work and WeakReference creation followed by forced collections in order to find the source of a memory problem.) The only other thing I found myself wanting was a “Back” button. Between my Windows Phone 7, Zune, and other things, I’ve grown very used to having a “back stack” that lets me just navigate back to where I came from. The ANTS MP interface is surprisingly easy to use given how much it lets you do, and once you start using it for any amount of time, you learn all of the different areas such that you know where to go. And it does remember the state of the areas you were previously in, of course. So if you go to, e.g., the Instance Retention Graph from the Class List and then return back to the Class List, it will remember which class you had selected and all that other state information. Still, a “Back” button would be a welcome addition to a future release. Bottom Line ANTS Memory Profiler is not an inexpensive tool. But my time is valuable. I can easily see ANTS MP saving me enough time tracking down memory problems to justify it on a cost basis. More importantly to me, knowing what is happening memory-wise in my programs and having the confidence that my code doesn’t have any hidden time bombs in it that will cause it to OOM if I leave it running for longer than I do when I spin it up real quickly for debugging or just to see how a new feature looks and feels is a good feeling. It’s a feeling that I like having and want to continue to have. I got the current version for free in order to review it. Having done so, I’ve now added it to my must-have tools and will gladly lay out the money for the next version when it comes out. It has a 14 day free trial, so if you aren’t sure if it’s right for you or if you think it seems interesting but aren’t really sure if it’s worth shelling out the money for it, give it a try.

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• WebCenter .NET Accelerator - Microsoft SharePoint Data via WSRP

  - by john.brunswick

  Platforms in the enterprise will never be homogeneous. As much as any vendor would enjoy having their single development or application technology be exclusively adopted by customers, too much legacy, time, education, innovation and vertical business needs exist to make using a single platform practical. JAVA and .NET are the two industry application platform heavyweights and more often than not, business users are leveraging various systems in their day to day activities that incorporate applications developed on top of both platforms. BEA Systems acquired Plumtree Software to complete their "liquid" view of data, stressing that regardless of a particular source system heterogeneous data could interoperate at not only through layers that allowed for data aggregation, but also at the "glass" or UI layer. The technical components that allowed the integration at the glass thrive today at Oracle, helping WebCenter to provide a rich composite application framework. Oracle Ensemble and the Oracle .NET Application Accelerator allow WebCenter to consume and interact with the UI layers provided by .NET applications and a series of other technologies. The beauty of the .NET accelerator is that it can consume any .NET application and act as a Web Services for Remote Portlets (WSRP) producer. I recently had a chance to leverage the .NET accelerator to expose a ASP .NET 2.0 (C#) application in the WebCenter UI (pictured above) and wanted to share a few tips to help others get started with similar integrations. I was using two virtual machines for the exercise - one with Windows Server 2003, running SharePoint and the other running WebCenter Spaces 11g. For my sample application data I ended up using SharePoint 2007 lists and calendars (MOSS 2007) to supply results using a .NET API for SharePoint.

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• “Big Data” Is A Small Concept Unless You Can Apply It To The Customer Experience

  - by Michael Hylton

  There’s been a lot of recent talk in the industry about “big data”.  Much can be said about the importance of big data and the results from it, but you need to always consider the customer experience when analyzing and applying customer data. Personalization and merchandising drive the user experience.  Big data should enable you to gain valuable insight into each of your customers and apply that insight at the moment they are on your Web site, talking to one of your call center agents, or any other touchpoint.  While past customer experience is important, you need to combine that with what your customer is doing on your Web site now as well what they are doing and saying on social networking sites.  It’s key to have a 360 degree view of your customer across all of your touchpoints in order to provide that relevant and consistent experience that they come to expect when interacting with your brand. Big data can enable you to effectively market, merchandize, and recommend the right products to the right customers and the right time.  By taking customer data and applying it to product recommendations, you have an opportunity to gain a greater share of wallet through the cross-selling and up-selling of additional products and services.  You can also build sustaining loyalty programs to continue to engage with your customers throughout their long-term relationship with your brand.

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• “Big Data” Is A Small Concept Unless You Can Apply It To The Customer Experience

  - by Michael Hylton

  There’s been a lot of recent talk in the industry about “big data”.  Much can be said about the importance of big data and the results from it, but you need to always consider the customer experience when analyzing and applying customer data. Personalization and merchandising drive the user experience.  Big data should enable you to gain valuable insight into each of your customers and apply that insight at the moment they are on your Web site, talking to one of your call center agents, or any other touchpoint.  While past customer experience is important, you need to combine that with what your customer is doing on your Web site now as well what they are doing and saying on social networking sites.  It’s key to have a 360 degree view of your customer across all of your touchpoints in order to provide that relevant and consistent experience that they come to expect when interacting with your brand. Big data can enable you to effectively market, merchandize, and recommend the right products to the right customers and the right time.  By taking customer data and applying it to product recommendations, you have an opportunity to gain a greater share of wallet through the cross-selling and up-selling of additional products and services.  You can also build sustaining loyalty programs to continue to engage with your customers throughout their long-term relationship with your brand.

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• Silverlight Cream for April 27, 2010 -- #849

  - by Dave Campbell

  In this Issue: Mike Snow, Kunal Chowdhury, Giorgetti Alessandro, Alexander Strauss, Corey Schuman, Kirupa, John Papa, Miro Miroslavov, Michael Washington, and Jeremy Likness. Shoutouts: Erik Mork and crew have posted their latest This Week In Silverlight April 23 2010 The Silverlight Team announced Microsoft releases Silverlight-powered Windows Intune beta Jesse Liberty has posted his UK and Ireland Slides and Links The Expression Blend and Design Blog reports a Minor Update to The Expression Blend 4 Release Candidate From SilverlightCream.com: Silverlight Tip of the Day #6 – Toast Notifications Mike Snow has Tip #6 up today and it's about Toast notifications in OOB apps: Restrictions, creation, showing, and the code. Silverlight Tutorials Chapter 2: Introduction to Silverlight Application Development Part 2 of Kunal Chowdhury's Introductory tutorial set is up ... he's covering how to create a Silverlight project, what's contained in it, and creating a User Control. Silverlight, M-V-VM ... and IoC - part 3 Giorgetti Alessandro has part 3 of his Silverlight, IOC, and MVVM series up... this one with an example using the code discussed previously. The project is on CodePlex, and he's not done with the series. Application Partitioning with MEF, Silverlight and Windows Azure – Part I Alexander Strauss is discussing Silverlight and MEF for loosely-coupled and partitioned apps. He's also using Azure in this discussion. geekSpeak Recording - Five Key Developer Features in Expression Blend with Corey Schuman Check out the latest geekSpeak on Channel 9 where Corey Schuman talks about the 5 key Developer Features in Expression Blend that will improve your productivity. Using the ChangePropertyAction Kirupa is discussing and demonstrating ChangePropertyAction. Check out the demo near the top of the post, then read how to do it, and download the source. 3 Free Silverlight Demos John Papa blogged about the 2 demos (with source) that have been updated to SL4, and a new one all by Microsoft Luminaries Karen Corby, Adam Kinney, Mark Rideout, Jesse Bishop, and John Papa: "ScrapBook", "HTML and Video Puzzle", and "Rich Notepad". Floating Visual Elements I like Miro Miroslavov's comment: "every Silverlight application “must” have some objects floating around in a quite 3D manner" :) ... well they do that on the CompletIT site, and this is part 2 of their explanation of how all that goodness works. MVVM – A Total Design Change Of Your Application With No Code With some Blend goodness, Michael Washington completely reorganizes the UI of an MVVM application without touching any code ... project included MVVM with Transaction and View Locator Example Jeremy Likness responded to reader requests and has an example up, with explanation, of marrying his last two posts: transactions with MVVM and View Model Locator. Stay in the 'Light! Twitter SilverlightNews | Twitter WynApse | WynApse.com | Tagged Posts | SilverlightCream Join me @ SilverlightCream | Phoenix Silverlight User Group Technorati Tags: Silverlight    Silverlight 3    Silverlight 4    Windows Phone MIX10

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• Can I configure a visual difference view with the notifications provided by TFS?

  - by John Kaster

  I have TFS sending me alerts whenever someone on my team checks in code. (I had to create notification rules for every project, but that's just a sidebar complaint in this question.) These alerts provided some information on who checked in the files when, and what files have changed, with urls to view details in a browser. The thing that baffles me is that I can't just click on the source file and see a visual diff of the changes. There's no link that will auto-launch a diff in Visual Studio (using a custom protocol) from there either. Is there a way to configure TFS to provide a visual diff of the changes to the file that was checked in via this notification UI?

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• Change in Job Title and Responsibilities

  - by John Conwell

  I've spent the past 7 years focused primarily on code and database performance.  It's an area that I have a passion for, as well as a propensity.  But what I've found is that its very hard to change the culture of a development environment.  You can teach performance, you can encourage performance, you might see slight shift in how devs think about performance.  But without full management backing and support you wont get long lasting changes in the development culture.  And in the end, you are back to being the "Perf Guy", fixing performance design flaws, after the fact, one by one by one. Which is why last year I asked my boss to changed my title and responsibilities to more naturally align with the team I was working for.  So now I'm a Computing Research Engineer (vague, I know), researching in the field of Big Data analytics and visualization. I've found this change revitalizing and a lot of fun.  And given the nature of Big Data (its, um…big) the performance aspects are always ever present.

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• css: zoooming-out inside the browser moves rightmost floated div below other divs

  - by John Sonderson

  I am seeing something strange in both firefox and chrome when I increase the zoom level inside these browsers, although I see nothing wrong with my CSS... I am hoping someone on this group will be able to help. Here is the whole story: I have a right-floated top-level div containing three right-floated right. The three inner divs have all box-model measurements in pixels which add up to the width of the enclosing container. Everything looks fine when the browser size is 100%, but when I start making the browser smaller with CTRL+scrollwheel or CTRL+minus the rightmost margin shrinks down too fast and eventually becomes zero, forcing my rightmost floated inner div to fall down below the other two! I can't make sense out of this, almost seems like some integer division is being performed incorrectly in the browser code, but alas firefox and chrome both display the same result. Here is the example (just zoom out with CTRL-minus to see what I mean): Click Here to View What I Mean on Example Site Just to narrow things down a bit, the tags of interest are the following: div#mainContent div#contentLeft div#contentCenter div#contentRight I've searched stackoverflow for an answer and found the following posts which seem related to my question but was not able to apply them to the problem I am experiencing: http:// stackoverflow.com/questions/6955313/div-moves-incorrectly-on-browser-resize http:// stackoverflow.com/questions/18246882/divs-move-when-resizing-page http:// stackoverflow.com/questions/17637231/moving-an-image-when-browser-resizes http:// stackoverflow.com/questions/5316380/how-to-stop-divs-moving-when-the-browser-is-resized I've duplicated the html and css code below for your convenience: Here is the HTML: <!doctype html> <html> <head> <meta charset="utf-8"> <title>Pinco</title> <link href="css/style.css" rel="stylesheet" type="text/css"> </head> <body> <div id="wrapper"> <header> <div class="logo"> <a href="http://pinco.com"> <img class="logo" src="images/PincoLogo5.png" alt="Pinco" /> </a> </div> <div class="titolo"> <h1>Benvenuti!</h1> <h2>Siete arrivati al sito pinco.</h2> </div> <nav> <ul class="menu"> <li><a href="#">Menù Qui</a></li> <li><a href="#">Menù Quo</a></li> <li><a href="#">Menù Qua</a></li> </ul> </nav> </header> <div id="mainContent"> <div id="contentLeft"> <section> <article> <p> Lorem ipsum dolor sit amet, consectetur adipiscing elit. Quisque tempor turpis est, nec varius est pharetra scelerisque. Sed eu pellentesque purus, at cursus nisi. In bibendum tristique nunc eu mattis. Nulla pretium tincidunt ipsum, non imperdiet metus tincidunt ac. In et lobortis elit, nec lobortis purus. Cras ac viverra risus. Proin dapibus tortor justo, a vulputate ipsum lacinia sed. In hac habitasse platea dictumst. Phasellus sit amet malesuada velit. Fusce diam neque, cursus id dui ac, blandit vehicula tortor. Phasellus interdum ipsum eu leo condimentum, in dignissim erat tincidunt. Ut fermentum consectetur tellus, dignissim volutpat orci suscipit ac. Praesent scelerisque urna metus. Vestibulum ante ipsum primis in faucibus orci luctus et ultrices posuere cubilia Curae; Duis pulvinar, sem a sodales eleifend, odio elit blandit risus, a dapibus ligula orci non augue. Nullam vitae cursus tortor, eget malesuada lectus. Nulla facilisi. Cras pharetra nisi sit amet orci dignissim, a eleifend odio hendrerit. </p> </article> </section> </div> <div id="contentCenter"> <section> <article> <p> Maecenas vitae purus at orci euismod pretium. Nam gravida gravida bibendum. Donec nec dolor vel magna consequat laoreet in a urna. Phasellus cursus ultrices lorem ut sagittis. Class aptent taciti sociosqu ad litora torquent per conubia nostra, per inceptos himenaeos. Vivamus purus felis, ornare quis ante vel, commodo scelerisque tortor. Integer vel facilisis mauris. </p> <img src="images/auto1.jpg" width="272" height="272" /> <p> In urna purus, fringilla a urna a, ultrices convallis orci. Duis mattis sit amet leo sed luctus. Donec nec sem non nunc mattis semper quis vitae enim. Cum sociis natoque penatibus et magnis dis parturient montes, nascetur ridiculus mus. Suspendisse dictum porta quam, vel lobortis enim bibendum et. Donec iaculis tortor id metus interdum, hendrerit tincidunt orci tempor. Sed dignissim cursus mattis. </p> </article> </section> </div> <div id="contentRight"> <section> <article> <img src="images/auto2.jpg" width="272" height="272" /> <img src="images/auto3.jpg" width="272" height="272" /> <p> Cras eu quam lobortis, sodales felis ultricies, rhoncus neque. Aenean nisi eros, blandit ac lacus sit amet, vulputate sodales mi. Nunc eget purus ultricies, aliquam quam sit amet, porttitor velit. In imperdiet justo in quam tristique, eget semper nisi pellentesque. Cras fringilla eros enim, in euismod nisl imperdiet ac. Fusce tempor justo vitae faucibus luctus. </p> </article> </section> </div> </div> <footer> <div class="footerText"> <p> Copyright &copy; Pinco <br />Lorem ipsum dolor sit amet, consectetur adipiscing elit. <br />Fusce ornare turpis orci, nec egestas leo feugiat ac. <br />Morbi eget sem facilisis, laoreet erat ut, tristique odio. Proin sollicitudin quis nisi id consequat. </p> </div> <div class="footerLogo"> <img class="footerLogo" src="images/auto4.jpg" width="80" height="80" /> </div> </footer> </div> </body> </html> and here is the CSS: /* CSS Document */ * { margin: 0; border: 0; padding: 0; } body { background: #8B0000; /* darkred */; } body { margin: 0; border: 0; padding: 0; } div#wrapper { margin: 0 auto; width: 960px; height: 100%; background: #FFC0CB /* pink */; } header { position: relative; background: #005b97; height: 140px; } header div.logo { float: left; width: 360px; height: 140px; } header div.logo img.logo { width: 360px; height: 140px; } header div.titolo { float: left; padding: 12px 0 0 35px; color: black; } header div.titolo h1 { font-size: 36px; font-weight: bold; } header div.titolo h2 { font-size: 24px; font-style: italic; font-weight: bold; color: white;} header nav { position: absolute; right: 0; bottom: 0; } header ul.menu { background: black; } header ul.menu li { display: inline-block; padding: 3px 15px; font-weight: bold; } div#mainContent { float: left; width: 100%; /* width: 960px; *//* height: 860px; */ padding: 30px 0; text-align: justify; } div#mainContent img { margin: 12px 0; } div#contentLeft { height: 900px; float: left; margin-left: 12px; border: 1px solid black; padding: 15px; width: 272px; background: #ccc; } div#contentCenter { height: 900px; float: left; margin-left: 12px; border: 1px solid transparent; padding: 15px; width: 272px; background: #E00; } div#contentRight { height: 900px; float: left; margin-left: 12px; border: 1px solid black; padding: 15px; width: 272px; background: #ccc; } footer { clear: both; padding: 12px; background: #306; color: white; height: 80px; font-style: italic; font-weight: bold; } footer div.footerText { float: left; } footer div.footerLogo { float: right; } a { color: white; text-decoration: none; } Thanks.

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• Freshen the RTS genre

  - by William Michael Thorley

  This isn't really a question, but a request for feedback. RPS (Rock, Paper, Scissors) RTS (Real Time Strategy) Demo version is out: The game is simple. It is an RTS. Why has it been made? Many if not most RTS’s are about economy and large numbers of unit types. The genre hasn’t actually developed the gameplay drastically from the very first RTS’s produced, some lesson have been learned, but the games are really very similar to how they have always been. RPS brings new gameplay to the RTS genre. Through three means: • New combat mechanics: RPS has two unique modes (as well as the old favourite) of resolving weapon fire. These change how combat happens, and make application of the correct units vital to success. From this comes the requirement to run Intel on your enemies. • Fixed Resource Economy: Each player has a fixed amount of energy, This means that there is a definite end to the game. You can attrition your enemy and try to outlast them, or try to outspend your opponent and destroy them. There is a limit to how fast ships can be built, through the generation of construction blocks, but energy is the fast limit on economy. • Game Modes: Game modes add victory conditions and new game pieces. The game is overseen by a controller which literally runs the game. Games are no longer line them up, gun them down. This means that new tactics must be played making skirmish games fresh with novel tactics without adding huge amounts of new game units to learn. I’ve produced RPS from the ground. I will be running a kickstarter in the near future, but right now I want feedback and input from the game developing community. Regarding the concepts, where RPS is going, the game modes, the combat mechanics. How it plays. RPS will give fresh gameplay to the genre so it must be right. It works over the internet or a LAN and supports single player games. Get it. Play it. Tell me about your games. Thank you Demo: https://dl.dropbox.com/u/51850113/RPS%20Playtest.zip Tutorials: https://dl.dropbox.com/u/51850113/RPSGamePlay.zip

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• Silverlight Cream for May 04, 2010 -- #855

  - by Dave Campbell

  In this Issue: John Papa, Adam Kinney, Mike Taulty, Kirupa, Gunnar Peipman, Mike Snow(-2-, -3-), Jesse Liberty, and Lee. Shoutout: Jeff Wilcox announced Silverlight Unit Test Framework: New version in the April 2010 Silverlight Toolkit From SilverlightCream.com: Silverlight TV 23: MVP Q&A with WWW (Wildermuth, Wahlin and Ward) John Papa has Silverlight 23 up which is a panel discussion between Shawn Wildermuth, Dan Wahlin, Ward Bell and John... wow... what a crew! Design-time Resources in Expression Blend 4 RC Adam Kinney reports on the new feature of Expresseion Blend RC to load resources at design time. Adam also has a project available to demonstrate the concepts he's explaining. Silverlight and WCF RIA Services (1 - Overview) Mike Taulty is starting a series on WCF RIA Services. This first one is an overview and looks to be a good series as expected. Introduction to Sample Data - Page 1 Kirupa has a great 5-part post up about sample data in Expression Blend. Windows Phone 7 development: Using WebBrowser control Gunnar Peipman posted about using the web browser control in WP7 to display RSS data. Good stuff, and all the code too. Silverlight Tip of the Day #10 – Converting Client IP to Geographical Location Mike Snow's Tip #10 is about taking an IP address and getting a geographical location from it. Combine this with his Tip #9 that retrieves the IP address. Silverlight Tip of the Day #11 – Deploying Silverlight Applications with WCF web services. Mike Snow's Tip #11 is much bigger than most ... it's almost an end-to-end solution for creating and deploying a WCF service, including resolving problems. Silverlight Tip of the Day #12 – Getting an Images Source File Name Mike Snow also has tip #12 up, and it's a quick one on getting the original source file name for an image you've loaded. Screen Scraping – When All You Have Is A Hammer… Jesse Liberty posted his solution to a self-imposed problem and ended up writing a 'mini tutorial on using Silverlight for creating desk-top utilities' ... all with source. RIA services and combobox lookups Lee has a post up about RIA Services and setting up comboboxes for lookups. Lots of source in the post and full project download. Stay in the 'Light! Twitter SilverlightNews | Twitter WynApse | WynApse.com | Tagged Posts | SilverlightCream Join me @ SilverlightCream | Phoenix Silverlight User Group Technorati Tags: Silverlight    Silverlight 3    Silverlight 4    Windows Phone MIX10

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• Will Google penalize subdomains if content is nearly identical

  - by John Pham

  I have created a subdomain for a town in San Diego that's ranking very well for it's keywords: http://carmelvalleymortgage.loanrebateinc.com/ I want to replicate this subdomain's content for another town in San Diego: http://sandiego.mortgage.loanrebateinc.com/ I will edit the text, tags, image files specific to each town, otherwise the verbiage will be identical. Question: Will Google penalize the main site? Will Google penalize the subdomains and list the content as spam? If yes to either 1 or 2, what strategies can I implement to prevent this? I'm using WordPress.

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• How to install Canon MP610 printer on Ubuntu 12.04 x64

  - by Arkadius

  I installed Ubuntu 12.04 x64. Orginal Canon drivers are only for 32-bit version. How can I install this printer in 64-bit version ? Arkadius HERE IS SOLUTION I looked for solution some time and finally found it. First I try to do it by adding repository like it is written here: http://www.iheartubuntu.com/2012/02/install-canon-printer-for-ubuntu-linux.html BUT it did NOT work. Printer was installed but every print JOB goes somewhere ( probably to /dev/null :) ) Also installing sudo apt-get install ia32-libs did NOT worked (it was already installed) Finally I found solution. NOTE I did NOT use orginal Canon drivers for 32-bit. I also removed drivers from repository: ppa:michael-gruz/canon I found solution almost at the end of this thread: http://ubuntuforums.org/showthread.php?t=1967725&page=10 Most important hint was found in Response #97 "Do NOT install any PPA" I did as follows: Removed all copies of my printer Removed Canon drivers from repository ppa:michael-gruz/canon sudo apt-get remove cnijfilter* Added new repository and installed CUPS for Canon: sudo apt-add-repository ppa:robbiew/cups-bjnp sudo apt-get update sudo apt-get install cups-bjnp Installed Gutenprint: sudo apt-get install printer-driver-gutenprint Restarted CUPS: sudo restart cups Add myself to group lp: sudo usermod -G lp -a your_user_name Added printer usings steps from link above: Don't install any PPA for the drivers. Click the Cog up in the right-hand corner and select Printers. Turn on the printer and make sure it is connected. When the Printers windows appears, click +Add and wait a few minutes. Your printer should appear within the configuration wizard. Mine did and its an Canon MX330. Click the defaults and continue on. Cups should identify your printer. I saw a few other models in the list. I was able to successfully print a test page afterwards. I hope this will also help someone else. Arkadius .

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• C#: Why Decorate When You Can Intercept

  - by James Michael Hare

  We've all heard of the old Decorator Design Pattern (here) or used it at one time or another either directly or indirectly.  A decorator is a class that wraps a given abstract class or interface and presents the same (or a superset) public interface but "decorated" with additional functionality.   As a really simplistic example, consider the System.IO.BufferedStream, it itself is a descendent of System.IO.Stream and wraps the given stream with buffering logic while still presenting System.IO.Stream's public interface:   1: Stream buffStream = new BufferedStream(rawStream); Now, let's take a look at a custom-code example.  Let's say that we have a class in our data access layer that retrieves a list of products from a database:  1: // a class that handles our CRUD operations for products 2: public class ProductDao 3: { 4: ... 5:  6: // a method that would retrieve all available products 7: public IEnumerable<Product> GetAvailableProducts() 8: { 9: var results = new List<Product>(); 10:  11: // must create the connection 12: using (var con = _factory.CreateConnection()) 13: { 14: con.ConnectionString = _productsConnectionString; 15: con.Open(); 16:  17: // create the command 18: using (var cmd = _factory.CreateCommand()) 19: { 20: cmd.Connection = con; 21: cmd.CommandText = _getAllProductsStoredProc; 22: cmd.CommandType = CommandType.StoredProcedure; 23:  24: // get a reader and pass back all results 25: using (var reader = cmd.ExecuteReader()) 26: { 27: while(reader.Read()) 28: { 29: results.Add(new Product 30: { 31: Name = reader["product_name"].ToString(), 32: ... 33: }); 34: } 35: } 36: } 37: }            38:  39: return results; 40: } 41: } Yes, you could use EF or any myriad other choices for this sort of thing, but the germaine point is that you have some operation that takes a non-trivial amount of time.  What if, during the production day I notice that my application is performing slowly and I want to see how much of that slowness is in the query versus my code.  Well, I could easily wrap the logic block in a System.Diagnostics.Stopwatch and log the results to log4net or other logging flavor of choice: 1:     // a class that handles our CRUD operations for products 2:     public class ProductDao 3:     { 4:         private static readonly ILog _log = LogManager.GetLogger(typeof(ProductDao)); 5:         ... 6:         7:         // a method that would retrieve all available products 8:         public IEnumerable<Product> GetAvailableProducts() 9:         { 10:             var results = new List<Product>(); 11:             var timer = Stopwatch.StartNew(); 12:             13:             // must create the connection 14:             using (var con = _factory.CreateConnection()) 15:             { 16:                 con.ConnectionString = _productsConnectionString; 17:                 18:                 // and all that other DB code... 19:                 ... 20:             } 21:             22:             timer.Stop(); 23:             24:             if (timer.ElapsedMilliseconds > 5000) 25:             { 26:                 _log.WarnFormat("Long query in GetAvailableProducts() took {0} ms", 27:                     timer.ElapsedMillseconds); 28:             } 29:             30:             return results; 31:         } 32:     } In my eye, this is very ugly.  It violates Single Responsibility Principle (SRP), which says that a class should only ever have one responsibility, where responsibility is often defined as a reason to change.  This class (and in particular this method) has two reasons to change: If the method of retrieving products changes. If the method of logging changes. Well, we could “simplify” this using the Decorator Design Pattern (here).  If we followed the pattern to the letter, we'd need to create a base decorator that implements the DAOs public interface and forwards to the wrapped instance.  So let's assume we break out the ProductDAO interface into IProductDAO using your refactoring tool of choice (Resharper is great for this). Now, ProductDao will implement IProductDao and get rid of all logging logic: 1:     public class ProductDao : IProductDao 2:     { 3:         // this reverts back to original version except for the interface added 4:     } 5:  And we create the base Decorator that also implements the interface and forwards all calls: 1:     public class ProductDaoDecorator : IProductDao 2:     { 3:         private readonly IProductDao _wrappedDao; 4:         5:         // constructor takes the dao to wrap 6:         public ProductDaoDecorator(IProductDao wrappedDao) 7:         { 8:             _wrappedDao = wrappedDao; 9:         } 10:         11:         ... 12:         13:         // and then all methods just forward their calls 14:         public IEnumerable<Product> GetAvailableProducts() 15:         { 16:             return _wrappedDao.GetAvailableProducts(); 17:         } 18:     } This defines our base decorator, then we can create decorators that add items of interest, and for any methods we don't decorate, we'll get the default behavior which just forwards the call to the wrapper in the base decorator: 1:     public class TimedThresholdProductDaoDecorator : ProductDaoDecorator 2:     { 3:         private static readonly ILog _log = LogManager.GetLogger(typeof(TimedThresholdProductDaoDecorator)); 4:         5:         public TimedThresholdProductDaoDecorator(IProductDao wrappedDao) : 6:             base(wrappedDao) 7:         { 8:         } 9:         10:         ... 11:         12:         public IEnumerable<Product> GetAvailableProducts() 13:         { 14:             var timer = Stopwatch.StartNew(); 15:             16:             var results = _wrapped.GetAvailableProducts(); 17:             18:             timer.Stop(); 19:             20:             if (timer.ElapsedMilliseconds > 5000) 21:             { 22:                 _log.WarnFormat("Long query in GetAvailableProducts() took {0} ms", 23:                     timer.ElapsedMillseconds); 24:             } 25:             26:             return results; 27:         } 28:     } Well, it's a bit better.  Now the logging is in its own class, and the database logic is in its own class.  But we've essentially multiplied the number of classes.  We now have 3 classes and one interface!  Now if you want to do that same logging decorating on all your DAOs, imagine the code bloat!  Sure, you can simplify and avoid creating the base decorator, or chuck it all and just inherit directly.  But regardless all of these have the problem of tying the logging logic into the code itself. Enter the Interceptors.  Things like this to me are a perfect example of when it's good to write an Interceptor using your class library of choice.  Sure, you could design your own perfectly generic decorator with delegates and all that, but personally I'm a big fan of Castle's Dynamic Proxy (here) which is actually used by many projects including Moq. What DynamicProxy allows you to do is intercept calls into any object by wrapping it with a proxy on the fly that intercepts the method and allows you to add functionality.  Essentially, the code would now look like this using DynamicProxy: 1: // Note: I like hiding DynamicProxy behind the scenes so users 2: // don't have to explicitly add reference to Castle's libraries. 3: public static class TimeThresholdInterceptor 4: { 5: // Our logging handle 6: private static readonly ILog _log = LogManager.GetLogger(typeof(TimeThresholdInterceptor)); 7:  8: // Handle to Castle's proxy generator 9: private static readonly ProxyGenerator _generator = new ProxyGenerator(); 10:  11: // generic form for those who prefer it 12: public static object Create<TInterface>(object target, TimeSpan threshold) 13: { 14: return Create(typeof(TInterface), target, threshold); 15: } 16:  17: // Form that uses type instead 18: public static object Create(Type interfaceType, object target, TimeSpan threshold) 19: { 20: return _generator.CreateInterfaceProxyWithTarget(interfaceType, target, 21: new TimedThreshold(threshold, level)); 22: } 23:  24: // The interceptor that is created to intercept the interface calls. 25: // Hidden as a private inner class so not exposing Castle libraries. 26: private class TimedThreshold : IInterceptor 27: { 28: // The threshold as a positive timespan that triggers a log message. 29: private readonly TimeSpan _threshold; 30:  31: // interceptor constructor 32: public TimedThreshold(TimeSpan threshold) 33: { 34: _threshold = threshold; 35: } 36:  37: // Intercept functor for each method invokation 38: public void Intercept(IInvocation invocation) 39: { 40: // time the method invocation 41: var timer = Stopwatch.StartNew(); 42:  43: // the Castle magic that tells the method to go ahead 44: invocation.Proceed(); 45:  46: timer.Stop(); 47:  48: // check if threshold is exceeded 49: if (timer.Elapsed > _threshold) 50: { 51: _log.WarnFormat("Long execution in {0} took {1} ms", 52: invocation.Method.Name, 53: timer.ElapsedMillseconds); 54: } 55: } 56: } 57: } Yes, it's a bit longer, but notice that: This class ONLY deals with logging long method calls, no DAO interface leftovers. This class can be used to time ANY class that has an interface or virtual methods. Personally, I like to wrap and hide the usage of DynamicProxy and IInterceptor so that anyone who uses this class doesn't need to know to add a Castle library reference.  As far as they are concerned, they're using my interceptor.  If I change to a new library if a better one comes along, they're insulated. Now, all we have to do to use this is to tell it to wrap our ProductDao and it does the rest: 1: // wraps a new ProductDao with a timing interceptor with a threshold of 5 seconds 2: IProductDao dao = TimeThresholdInterceptor.Create<IProductDao>(new ProductDao(), 5000); Automatic decoration of all methods!  You can even refine the proxy so that it only intercepts certain methods. This is ideal for so many things.  These are just some of the interceptors we've dreamed up and use: Log parameters and returns of methods to XML for auditing. Block invocations to methods and return default value (stubbing). Throw exception if certain methods are called (good for blocking access to deprecated methods). Log entrance and exit of a method and the duration. Log a message if a method takes more than a given time threshold to execute. Whether you use DynamicProxy or some other technology, I hope you see the benefits this adds.  Does it completely eliminate all need for the Decorator pattern?  No, there may still be cases where you want to decorate a particular class with functionality that doesn't apply to the world at large. But for all those cases where you are using Decorator to add functionality that's truly generic.  I strongly suggest you give this a try!

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