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• Violation of the DRY Principle

  - by Onorio Catenacci

  I am sure there's a name for this anti-pattern somewhere; however I am not familiar enough with the anti-pattern literature to know it. Consider the following scenario: or0 is a member function in a class. For better or worse, it's heavily dependent on class member variables. Programmer A comes along and needs functionality like or0 but rather than calling or0, Programmer A copies and renames the entire class. I'm guessing that she doesn't call or0 because, as I say, it's heavily dependent on member variables for its functionality. Or maybe she's a junior programmer and doesn't know how to call it from other code. So now we've got or0 and c0 (c for copy). I can't completely fault Programmer A for this approach--we all get under tight deadlines and we hack code to get work done. Several programmers maintain or0 so it's now version orN. c0 is now version cN. Unfortunately most of the programmers that maintained the class containing or0 seemed to be completely unaware of c0--which is one of the strongest arguments I can think of for the wisdom of the DRY principle. And there may also have been independent maintainance of the code in c. Either way it appears that or0 and c0 were maintained independent of each other. And, joy and happiness, an error is occurring in cN that does not occur in orN. So I have a few questions: 1.) Is there a name for this anti-pattern? I've seen this happen so often I'd find it hard to believe this is not a named anti-pattern. 2.) I can see a few alternatives: a.) Fix orN to take a parameter that specifies the values of all the member variables it needs. Then modify cN to call orN with all of the needed parameters passed in. b.) Try to manually port fixes from orN to cN. (Mind you I don't want to do this but it is a realistic possibility.) c.) Recopy orN to cN--again, yuck but I list it for sake of completeness. d.) Try to figure out where cN is broken and then repair it independently of orN. Alternative a seems like the best fix in the long term but I doubt the customer will let me implement it. Never time or money to fix things right but always time and money to repair the same problem 40 or 50 times, right? Can anyone suggest other approaches I may not have considered? If you were in my place, which approach would you take? If there are other questions and answers here along these lines, please post links to them. I don't mind removing this question if it's a dupe but my searching hasn't turned up anything that addresses this question yet. EDIT: Thanks everyone for all the thoughtful responses. I asked about a name for the anti-pattern so I could research it further on my own. I'm surprised this particular bad coding practice doesn't seem to have a "canonical" name for it.

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• Link instead of Attaching

  - by Daniel Moth

  With email storage not being an issue in many companies (I think I currently have 25GB of storage on my email account, I don’t even think about storage), this encourages bad behaviors such as liberally attaching office documents to emails instead of sharing a link to the document in SharePoint or SkyDrive or some file share etc. Attaching a file admittedly has its usage scenarios too, but it should not be the default. I thought I'd list the reasons why sharing a link can be better than attaching files directly. In no particular order: Better Review. It allows multiple recipients to review the file and their comments are aggregated into a single document. The alternative is everyone having to detach the document, add their comments, then send back to you, and then you have to collate. Wirth the alternative, you also potentially miss out on recipients reading comments from other recipients. Always up to date. The attachment becomes a fork instead of an always up to date document. For example, you send the email on Thursday, I only open it on Tuesday: between those days you could have made updates that now I am missing because you decided to share a link instead of an attachment. Better bookmarking. When I need to find that document you shared, you are forcing me to search through my email (I may not even be running outlook), instead of opening the link which I have bookmarked in my browser or my collection of links in my OneNote or from the recent/pinned links of the office app on my task bar, etc. Can control access. If someone accidentally or naively forwards your link to someone outside your group/org who you’d prefer not to have access to it, the location of the document can be protected with specific access control. Can add more recipients. If someone adds people to the email thread in outlook, your attachment doesn't get re-attached - instead, the person added is left without the attachment unless someone remembers to re-attach it. If it was a link, they are immediately caught up without further actions. Enable Discovery. If you put it on a share, I may be able to discover other cool stuff that lives alongside that document. Save on storage. So this doesn't apply to me given my opening statement, but if in your company you do have such limitations, attaching files eats up storage on all recipients accounts and will also get "lost" when those people archive email (and lose completely at some point if they follow the company retention policy). Like I said, attachments do have their place, but they should be an explicit choice for explicit reasons rather than the default. Comments about this post by Daniel Moth welcome at the original blog.

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• Use Expressions with LINQ to Entities

  - by EltonStoneman

  [Source: http://geekswithblogs.net/EltonStoneman] Recently I've been putting together a generic approach for paging the response from a WCF service. Paging changes the service signature, so it's not as simple as adding a behavior to an existing service in config, but the complexity of the paging is isolated in a generic base class. We're using the Entity Framework talking to SQL Server, so when we ask for a page using LINQ's .Take() method we get a nice efficient SQL query for just the rows we want, with minimal impact on SQL Server and network traffic. We use the maximum ID of the record returned as a high-water mark (rather than using .Skip() to go to the next record), so the approach caters for records being deleted between page requests. In the paged response we include a HasMorePages indicator, computed by comparing the max ID in the page of results to the max ID for the whole resultset - if the latter is bigger, then there are more pages. In some quick performance testing, the paged version of the service performed much more slowly than the unpaged version, which was unexpected. We narrowed it down to the code which gets the max ID for the full resultset - instead of building an efficient MAX() SQL query, EF was returning the whole resultset and then computing the max ID in the service layer. It's easy to reproduce - take this AdventureWorks query:             var context = new AdventureWorksEntities();             var query = from od in context.SalesOrderDetail                         where od.ModifiedDate >= modified                          && od.SalesOrderDetailID.CompareTo(id) > 0                         orderby od.SalesOrderDetailID                         select od;   We can find the maximum SalesOrderDetailID like this:             var maxIdEfficiently = query.Max(od => od.SalesOrderDetailID);   which produces our efficient MAX() SQL query. If we're doing this generically and we already have the ID function in a Func:             Func<SalesOrderDetail, int> idFunc = od => od.SalesOrderDetailID;             var maxIdInefficiently = query.Max(idFunc);   This fetches all the results from the query and then runs the Max() function in code. If you look at the difference in Reflector, the first call passes an Expression to the Max(), while the second call passes a Func. So it's an easy fix - wrap the Func in an Expression:             Expression<Func<SalesOrderDetail, int>> idExpression = od => od.SalesOrderDetailID;             var maxIdEfficientlyAgain = query.Max(idExpression);   - and we're back to running an efficient MAX() statement. Evidently the EF provider can dissect an Expression and build its equivalent in SQL, but it can't do that with Funcs.

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• DTLoggedExec 1.1.2008.4 Released!

  - by Davide Mauri

  Today I've relased the latest version of my DTExec replacement tool, DTLoggedExec. The main changes are the following: Used a new strategy for version numbers. Now it will follow the following pattern Major.Minor.TargetSQLServerVersion.Revision Added support for Auto Configurations Fixed a bug that reported incorrect number of errors and warnings to Log Providers Fixed a buf that prevented correct casting of values when using /Set and /Param options Errors and Warnings are now counted more precisely. Updated database and log import scripts to categorize logs by projects and sections. E.g.: Project: MyBIProject; Sections: Staging, Datawarehouse Removed unused report stored procedures from database Updated Samples: 12 samples are now available to show ALL DTLoggedExec features From this version only SSIS 2008 will be supported http://dtloggedexec.codeplex.com/releases/view/62218  It useful to say something more on a couple of specific points: From this version only SSIS 2008 will be supportedYes, Integration Services 2005 are not supported anymore. The latest version capable of running SSIS 2005 Packages is the 1.0.0.2. Updated database and log import scripts to categorize logs by projects and sectionsWhen you import a log file, you can now assign it to a Project and to a Section of that project. In this way it's easier to gather statistical information for an entire project or a subsection of it. This also allows to store logged data of package belonging to different projects in the same database. For example:  Updated SamplesA complete set of samples that shows how to use all DTLoggedExec features are now shipped with the product. Enjoy! Added support for Auto ConfigurationsThis point will have a post on its own, since it's quite important and is by far the biggest new feature introduced in this release. To explain it in a few words, I can just say that you don't need to waste time with complex DTS configuration files or options, since a package will configure itself automatically. You just need to write a single statement as a parameter for DTLoggedExec. This feature can simplify deployment *a lot* :)   I the next days I'll write the mentioned post on Auto-Configurations and i'll update the documentation available on theDTLoggedExec website:   http://dtloggedexec.davidemauri.it/MainPage.ashx

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• Property overwrite behaviour

  - by jeremyj

  I thought it worth sharing about property overwrite behaviour because i found it confusing at first in the hope of preventing some learning pain for the uninitiated with MSBuild :-)The confusion for me came because of the redundancy of using a Condition statement in a _project_ level property to test that a property has not been previously set. What i mean is that the following two statements are always identical in behaviour, regardless if the property has been supplied on the command line -  <PropertyGroup>    <PropA Condition=" '$(PropA)' == '' ">PropA set at project level</PropA>  </PropertyGroup>has the same behaviour regardless of command line override as -  <PropertyGroup>     <PropA>PropA set at project level</PropA>   </PropertyGroup>  i.e. the two above property declarations have the same result whether the property is overridden on the command line or not.To prove this experiment with the following .proj file -<?xml version="1.0" encoding="utf-8"?><Project ToolsVersion="4.0" >  <PropertyGroup>    <PropA Condition=" '$(PropA)' == '' ">PropA set at project level</PropA>  </PropertyGroup>  <Target Name="Target1">    <Message Text="PropA: $(PropA)"/>  </Target>  <Target Name="Target2">    <PropertyGroup>      <PropA>PropA set in Target2</PropA>    </PropertyGroup>    <Message Text="PropA: $(PropA)"/>  </Target>  <Target Name="Target3">    <PropertyGroup>      <PropA Condition=" '$(PropA)' == '' ">PropA set in Target3</PropA>    </PropertyGroup>    <Message Text="PropA: $(PropA)"/>  </Target>  <Target Name="Target4">    <PropertyGroup>      <PropA Condition=" '$(PropA)' != '' ">PropA set in Target4</PropA>    </PropertyGroup>    <Message Text="PropA: $(PropA)"/>  </Target></Project>Try invoking it using both of the following invocations and observe its output -1)>msbuild blog.proj /t:Target1;Target2;Target3;Target42)>msbuild blog.proj /t:Target1;Target2;Target3;Target4 "/p:PropA=PropA set on command line"Then try those two invocations with the following three variations of specifying PropA at the project level -1)  <PropertyGroup>     <PropA Condition=" '$(PropA)' == '' ">PropA set at project level</PropA>   </PropertyGroup> 2)   <PropertyGroup>     <PropA>PropA set at project level</PropA>   </PropertyGroup>3)  <PropertyGroup>     <PropA Condition=" '$(PropA)' != '' ">PropA set at project level</PropA>   </PropertyGroup>

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• ClearTrace Performance on 170GB of Trace Files

  - by Bill Graziano

  I’ve always worked to make ClearTrace perform well.  That’s probably because I spend so much time watching it work.  I’m often going through two or three gigabytes of trace files but I rarely get the chance to run it on a really large set of files. One of my clients wanted to run a full trace for a week and then analyze the results.  At the end of that week we had 847 200MB trace files for a total of nearly 170GB. I regularly use 200MB trace files when I monitor production systems.  I usually get around 300,000 statements in a file that size if it’s mostly stored procedures.  So those 847 trace files contained roughly 250 million statements.  (That’s 730 bytes per statement if you’re keeping track.  Newer trace files have some compression in them but I’m not exactly sure what they’re doing.)  On a system running 1,000 statements per second I get a new file every five minutes or so. It took 27 hours to process these files on an older development box.  That works out to 1.77MB/second.  That means ClearTrace processed about 2,654 statements per second. You can query the data while you’re loading it but I’ve found it works better to use a second instance of ClearTrace to do this.  I’m not sure why yet but I think there’s still some dependency between the two processes. ClearTrace is almost always CPU bound.  It’s really just a huge, ugly collection of regular expressions.  It only writes a summary to its database at the end of each trace file so that usually isn’t a bottleneck.  At the end of this process, the executable was using roughly 435MB of RAM.  Certainly more than when it started but I think that’s acceptable. The database where all this is stored started out at 100MB.  After processing 170GB of trace files the database had grown to 203MB.  The space savings are due to the “datawarehouse-ish” design and only storing a summary of each trace file. You can download ClearTrace for SQL Server 2008 or test out the beta version for SQL Server 2012.  Happy Tuning!

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• Microsoft Certifications &ndash; how to prep? and why?

  - by Kelly Jones

  I often get asked by my colleagues, “how do you prepare for Microsoft exams?” Well, the answer for me is a little complicated, so I thought I’d write up here what I do. The first thing I do is go to Microsoft’s website to find the exam that I need to take.  If you’re looking to get a particular certification, then their site lists the exam or exams that you’ll need to pass.  If you’ve already taken an exam, you can log onto the MCP website and use their certification planner.  This little tool tells you what tests you need, based on the exams you’ve already passed.  It is very helpful with the certifications that are multiple tests and especially ones that have electives. Once you’ve identified the test, you can use Microsoft’s website to see the topics that it covers.  This is a good outline to follow when you study.  I’ll keep this handy to reference back throughout my studying to make sure that I’m covering all the topics I need to know. The next step is probably where I am a little different from others.  IF the exam outline covers material that I’ve already been working with, then I’ll skip a lot of the studying and go directly to the practice tests.  However, if I’m looking at the outline and wondering how in the world do you do that? – then it’s time to hit the books. So, where to find study materials?  Try typing in the exam number into any search engine.  You’ll typically find a ton of resources.  If you’re lucky, you’ll find books that others recommend based on their studying and exam experience.  As a Sogeti employee, I have access to three really good resources: an internal company list of all of the consultants who have passed particular tests (on our Connex website), Books 24x7, and Transcender practice exams. Once my studying is done (either through books or experience), I’ll go through the practice exams.  I find them really helpful in getting my knowledge lined up to the thinking process that the exam writers use.  If I’m relying on my experience, then this really helps me to identify gaps in my knowledge that I’ll need to fill. That’s about it.  If I’m doing ok on the practice exams, then I’ll take the real thing.  I’ve found that the practice exams are usually more difficult than then real thing. Oh – one other thing I do related to Microsoft exams – I try to take any beta exams that Microsoft makes available that fall into my skill set.  Microsoft has started a blog to announce these and the seats usually fill up really quick.  The blog is at http://blogs.technet.com/betaexams/ . You don’t get your results instantly, like a normal exam, instead you have to wait for everyone to finish taking the beta exams and for Microsoft to determine which questions they are using and which they are dropping.  So, be prepared to wait six to eight weeks for your results.

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• Is OOP hard because it is not natural?

  - by zvrba

  One can often hear that OOP naturally corresponds to the way people think about the world. But I would strongly disagree with this statement: We (or at least I) conceptualize the world in terms of relationships between things we encounter, but the focus of OOP is designing individual classes and their hierarchies. Note that, in everyday life, relationships and actions exist mostly between objects that would have been instances of unrelated classes in OOP. Examples of such relationships are: "my screen is on top of the table"; "I (a human being) am sitting on a chair"; "a car is on the road"; "I am typing on the keyboard"; "the coffee machine boils water", "the text is shown in the terminal window." We think in terms of bivalent (sometimes trivalent, as, for example in, "I gave you flowers") verbs where the verb is the action (relation) that operates on two objects to produce some result/action. The focus is on action, and the two (or three) [grammatical] objects have equal importance. Contrast that with OOP where you first have to find one object (noun) and tell it to perform some action on another object. The way of thinking is shifted from actions/verbs operating on nouns to nouns operating on nouns -- it is as if everything is being said in passive or reflexive voice, e.g., "the text is being shown by the terminal window". Or maybe "the text draws itself on the terminal window". Not only is the focus shifted to nouns, but one of the nouns (let's call it grammatical subject) is given higher "importance" than the other (grammatical object). Thus one must decide whether one will say terminalWindow.show(someText) or someText.show(terminalWindow). But why burden people with such trivial decisions with no operational consequences when one really means show(terminalWindow, someText)? [Consequences are operationally insignificant -- in both cases the text is shown on the terminal window -- but can be very serious in the design of class hierarchies and a "wrong" choice can lead to convoluted and hard to maintain code.] I would therefore argue that the mainstream way of doing OOP (class-based, single-dispatch) is hard because it IS UNNATURAL and does not correspond to how humans think about the world. Generic methods from CLOS are closer to my way of thinking, but, alas, this is not widespread approach. Given these problems, how/why did it happen that the currently mainstream way of doing OOP became so popular? And what, if anything, can be done to dethrone it?

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• Create simple jQuery plugin

  - by ybbest

  In the last post, I have shown you how to add the function to jQuery. In this post, I will show you how to create plugin to achieve this. 1. You need to wrap your code in the following construct, this is because you should not use $ directly as $ is global variable, it could have clash with some other library which also use $.Basically, you can pass in jQuery object into the function, so that $ is made available inside the function. (JavaScript use function to create scope, so you can make sure $ is referred to jQuery inside the function ) (function($){ //Your code goes here. }; })(jQuery); 2. Put your code into the construct above. (function ($) { $.getParameterByName = function (name) { name = name.replace(/[\[]/, "\\\[").replace(/[\]]/, "\\\]"); var regexS = "[\\?&]" + name + "=([^&#]*)"; var regex = new RegExp(regexS); var results = regex.exec(window.location.search); if (results == null) return ""; else return decodeURIComponent(results[1].replace(/\+/g, " ")); }; })(jQuery); 3. Now you can reference the code into you project and you can call the method in you JavaScript References: Provides scope for variables Variables are scoped at the function level in javascript. This is different to what you might be used to in a language like C# or Java where the variables are scoped to the block. What this means is if you declare a variable inside a loop or an if statement, it will be available to the entire function. If you ever find yourself needing to explicitly scope a variable inside a function you can use an anonymous function to do this. You can actually create an anonymous function and then execute it straight away and all the variables inside will be scoped to the anonymous function: (function() { var myProperty = "hello world"; alert(myProperty); })(); alert(typeof(myProperty)); // undefined How does an anonymous function in JavaScript work? Building Your First jQuery Plugin A Plugin Development Pattern

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• [JAVA]How to make my Oracle update/insert action through JAVA faster?

  - by gunbuster363

  [JAVA]How to make my Oracle update/insert action through JAVA faster? Hi everyone, I am facing a problem in my company that is - our program's speed is not fast enough. To be more specific, we are telecommunication company and this program handle call/internet serfing transaction made by every mobile phone users in our city. Because the amount of download content made by the iphone users is just too much, our program cannot handle them fast enough. The situation is, the amount of transaction made by users are double of the transaction processed by our program. Most of the running time of the program are dominated by DB transactions. I've search through the internet and browsed some sites ( for example: http://www.javaperformancetuning.com/tips/rawtips.shtml ) talking about java performace in DB, but I cannot find a suggestion suitable for us. these advices are not applicable/already used, for instance: 1)Use prepared statements. Use parametrized SQL Already used prepared statement. Each time will use different parameter by clear parameters and set parameters. 2)Tune the SQL to minimize the data returned (e.g. not 'SELECT *'). Sure, already used. 3)Use connection pooling. We hold a single connection during the program's execution. And I doubt that pooling cannot solve the problem because our program act as 1 user, so there are no problem for concurrent access to DB. If anyone of you think pooling is good, please tell me why. Thanks. 4)Try to combine queries and batch updates. Cannot do it. Every query/insert/update is depend on the database's information. For example, we look up the DB for the client's information, if we cannot find his usage, we insert the usage into DB, otherwise we do update. 5)Close resources (Connections, Statements, ResultSets) when finished Sure. 6)Select the fastest JDBC driver. I don't know. I've search on the internet about the type of driver available and I am very confused. We use oracle.jdbc.driver.OracleDriver and we use thin instead of oci, that's all I know. In addition, our program is a two-tier way ( java <- oracle ) 7)turn off auto-commit already done that. Looking forwards to any helps, thank you very much.

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• Drive

  - by erikanollwebb

  Picking up where we left off, let's summarize.  People have both intrinsic motivation and extrinsic motivation, and whether reward works depends a bit on what you are rewarding.  Rewards don't decreased intrinsic motivation provided you know what you are getting and why, and when you reward high performance.  But as anyone who has watched the great animation of Dan Pink's TED talk knows, even that doesn't tell the whole story.  Although people may not be less intrinsically motivated by rewards, the impact of rewards on actual performance is a really odd questions.  Larger rewards don't necessarily lead to better performance and in fact, some times lead to worse performance.  Pink argues that people are driven and engaged when they have autonomy, mastery and purpose.  If they can self-direct and can be good at what they do and have a sense of purpose for what they are doing, they show the highest engagement.   (Personally, I would add progress to the list.  My experience is that if you have autonomy, mastery and a sense of purpose but don't get a feeling that you are making any progress day to day, your level of engagement will drop rapidly.) So Pink is arguing if we could set up work so that people have a sense of purpose in what they do, have some autonomy and the ability to build mastery, you'll have better companies.  And that's probably true in a lot of ways, but there's a problem.  Sometimes, you have things you need to do but maybe you don't really want to do.  Or that you don't really see the point of.  Or that doesn't have a lot of value to you at the end of the day.  Then what does a company do?  Let me give you an example.  I've worked on some customer relationship management (CRM) tools over the years and done user research with sales people to try and understand their world.  And there's a funny thing about sales tools in CRM.  Sometimes what the company wants a sales person to do is at odds with what a sales person thinks is useful to them.  For example, companies would like to know who a sales person talked to at the company and the person level.  They'd like to know what they talked about, when, and whether the deals closed.  Those metrics would help you build a better sales force and understand what works and what does not.  But sales people see that as busy work that doesn't add any value to their ability to sell.  So you have a sales person who has a lot of autonomy, they like to do things that improve their ability to sell and they usually feel a sense of purpose--the group is trying to make a quota!  That quota will help the company succeed!  But then you have tasks that they don't think fit into that equation.  The company would like to know more about what makes them successful and get metrics on what they do and frankly, have a record of what they do in case they leave, but the sales person thinks it's a waste of time to put all that information into a sales application. They have drive, just not for all the things the company would like.   You could punish them for not entering the information, or you could try to reward them for doing it, but you still have an imperfect model of engagement.  Ideally, you'd like them to want to do it.  If they want to do it, if they are motivated to do it, then the company wins.  If *something* about it is rewarding to them, then they are more engaged and more likely to do it.  So the question becomes, how do you create that interest to do something?

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• How do you make a bullet ricochet off a vertical wall?

  - by Bagofsheep

  First things first. I am using C# with XNA. My game is top-down and the player can shoot bullets. I've managed to get the bullets to ricochet correctly off horizontal walls. Yet, despite using similar methods (e.g. http://stackoverflow.com/questions/3203952/mirroring-an-angle) and reading other answered questions about this subject I have not been able to get the bullets to ricochet off a vertical wall correctly. Any method I've tried has failed and sometimes made ricocheting off a horizontal wall buggy. Here is the collision code that calls the ricochet method: //Loop through returned tile rectangles from quad tree to test for wall collision. If a collision occurs perform collision logic. for (int r = 0; r < returnObjects.Count; r++) if (Bullets[i].BoundingRectangle.Intersects(returnObjects[r])) Bullets[i].doCollision(returnObjects[r]); Now here is the code for the doCollision method. public void doCollision(Rectangle surface) { if (Ricochet) doRicochet(surface); else Trash = true; } Finally, here is the code for the doRicochet method. public void doRicochet(Rectangle surface) { if (Position.X > surface.Left && Position.X < surface.Right) { //Mirror the bullet's angle. Rotation = -1 * Rotation; //Moves the bullet in the direction of its rotation by given amount. moveFaceDirection(Sprite.Width * BulletScale.X); } else if (Position.Y > surface.Top && Position.Y < surface.Bottom) { } } Since I am only dealing with vertical and horizontal walls at the moment, the if statements simply determine if the object is colliding from the right or left, or from the top or bottom. If the object's X position is within the boundaries of the tile's X boundaries (left and right sides), it must be colliding from the top, and vice verse. As you can see, the else if statement is empty and is where the correct code needs to go.

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• Things to do After installing Visual Studio Express 12.

  - by Anirudha

  Originally posted on: http://geekswithblogs.net/anirugu/archive/2013/06/25/things-to-do-after-install-visual-studio-express-12.aspx  1. Environment > Document > Check the option for auto-load changes. By checking this option You can modified the file outside the VWD and VWD don’t tell you for confirmation. 2. Environment > Tabs and Windows > Preview Tab > uncheck the solution Explorer option. This option don’t show you the file when you just click on them in solution explorer. 3. Project and solutions > Check the track active item in solution explorer This option help you to easily figure out which file you working on and where it is in solution explorer . 4. text editor > all settings > word wrap > check this feature to enable word wrap 5. Text-editor > Css > formatting > check the compact rule. this option make you file smaller in size and easily to read. 6. Text-editor > html > miscellaneous > uncheck the auto ID option. Actually When you copy paste the html code Visual studio change their ID if ID is already exist. this option disable that feature. This is useful to do when we write if{} else {} statement and this is not helpful on that case. 7. Package manager > General > browse > copy the location of cache folder and in package source add them as source. This way you can use package that you have use earlier when you are offline. Thanks for read my post

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• Accessing Controls Within A Gridview

  - by Bunch

  Sometimes you need to access a control within a GridView, but it isn’t quite as straight forward as just using FindControl to grab the control like you can in a FormView. Since the GridView builds multiple rows the key is to specify the row. In this example there is a GridView with a control for a player’s errors. If the errors is greater than 9 the GridView should display the control (lblErrors) in red so it stands out. Here is the GridView: <asp:GridView ID="gvFielding" runat="server" DataSourceID="sqlFielding" DataKeyNames="PlayerID" AutoGenerateColumns="false" >     <Columns>         <asp:BoundField DataField="PlayerName" HeaderText="Player Name" />         <asp:BoundField DataField="PlayerNumber" HeaderText="Player Number" />         <asp:TemplateField HeaderText="Errors">             <ItemTemplate>                 <asp:Label ID="lblErrors" runat="server" Text='<%# EVAL("Errors") %>'  />             </ItemTemplate>         </asp:TemplateField>     </Columns> </asp:GridView> In the code behind you can add the code to change the label’s ForeColor property to red based on the amount of errors. In this case 10 or more errors triggers the color change. Protected Sub gvFielding_DataBound(ByVal sender As Object, ByVal e As System.EventArgs) Handles gvFielding.DataBound     Dim errorLabel As Label     Dim errors As Integer     Dim i As Integer = 0     For Each row As GridViewRow In gvFielding.Rows         errorLabel = gvFielding.Rows(i).FindControl("lblErrors")         If Not errorLabel.Text = Nothing Then             Integer.TryParse(errorLabel.Text, errors)             If errors > 9 Then                 errorLabel.ForeColor = Drawing.Color.Red             End If         End If         i += 1     Next End Sub The main points in the DataBound sub is use a For Each statement to loop through the rows and to increment the variable i so you loop through every row. That way you check each one and if the value is greater than 9 the label changes to red. The If Not errorLabel.Text = Nothing line is there as a check in case no data comes back at all for Errors. Technorati Tags: GridView,ASP.Net,VB.Net

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• Capture a Query Executed By An Application Or User Against a SQL Server Database in Less Than a Minute

  - by Compudicted

  At times a Database Administrator, or even a developer is required to wear a spy’s hat. This necessity oftentimes is dictated by a need to take a glimpse into a black-box application for reasons varying from a performance issue to an unauthorized access to data or resources, or as in my most recent case, a closed source custom application that was abandoned by a deserted contractor without source code. It may not be news or unknown to most IT people that SQL Server has always provided means of back-door access to everything connecting to its database. This indispensible tool is SQL Server Profiler. This “gem” is always quietly sitting in the Start – Programs – SQL Server <product version> – Performance Tools folder (yes, it is for performance analysis mostly, but not limited to) ready to help you! So, to the action, let’s start it up. Once ready click on the File – New Trace button, or using Ctrl-N with your keyboard. The standard connection dialog you have seen in SSMS comes up where you connect the standard way: One side note here, you will be able to connect only if your account belongs to the sysadmin or alter trace fixed server role. Upon a successful connection you must be able to see this initial dialog: At this stage I will give a hint: you will have a wide variety of predefined templates: But to shorten your time to results you would need to opt for using the TSQL_Grouped template. Now you need to set it up. In some cases, you will know the principal’s login name (account) that needs to be monitored in advance, and in some (like in mine), you will not. But it is VERY helpful to monitor just a particular account to minimize the amount of results returned. So if you know it you can already go to the Event Section tab, then click the Column Filters button which would bring a dialog below where you key in the account being monitored without any mask (or whildcard):  If you do not know the principal name then you will need to poke around and look around for things like a config file where (typically!) the connection string is fully exposed. That was the case in my situation, an application had an app.config (XML) file with the connection string in it not encrypted: This made my endeavor very easy. So after I entered the account to monitor I clicked on Run button and also started my black-box application. Voilà, in a under a minute of time I had the SQL statement captured:

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• Multi-Part Map Troubleshooting

  - by Michael Stephenson

  Scenario I came across a nice little one with multi-part maps the other day. I had an orchestration where I needed to combine 4 input messages into one output message like in the below table:   Input Messages Output Messages Company Details Member Details Event Message Member Search Member Import   I thought my orchestration was working fine but for some reason when I was trying to send my message it had no content under the root node like below <ns0:ImportMemberChange xmlns:ns0="http://---------------/"></ns0:ImportMemberChange>   My map is displayed in the below picture. I knew that the member search message may not have any elements under it but its root element would always exist. The rest of the messages were expected to be fully populated. I tried a number of different things and testing my map outside of the orchestration it always worked fine. The Eureka Moment The eureka moment came when I was looking at the xslt produced by the map. Even though I'd tried swapping the order of the messages in the input of the map you can see in the below picture that the first part of the processing of the message (with the red circle around it) is doing a for-each over the GetCompanyDetailsResult element within the GetCompanyDetailsResponse message. This is because the processing is driven by the output message format and the first element to output is the OrganisationID which comes from the GetCompanyDetailsResponse message. At this point I could focus my attention on this message as the xslt shows that if this xpath statement doesn’t return the an element from the GetCompanyDetailsResponse message then the whole body of the output message will not be produced and the output from the map would look like the message I was getting. <ns0:ImportMemberChange xmlns:ns0="http://---------------/"></ns0:ImportMemberChange> I was quickly able to prove this in my map test which proved this was a likely candidate for the problem. I revisited the orchestration focusing on the creation of the GetCompanyDetailsResponse message and there was actually a bug in the orchestration which resulted in the message being incorrectly created, once this was fixed everything worked as expected. Conclusion Originally I thought it was a problem with the map itself, and looking online there wasn’t really much in the way of content around troubleshooting for multi-part map problems so I thought I'd write this up. I guess technically it isn't a multi-part map problem, but I spend a good couple of hours the other day thinking it was.

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• Software Center seems to freeze system when installing, syslog has "blocked for more than 120 seconds" errors

  - by nbm

  12.04 (precise) 64-bit Kernel Linux 3.2.0-39 3.6GB memory Intel Core 2 Duo CPU @ 2.40GHz x2 WUBI-installed Ubuntu running on a MacBook Pro 7.1 with OSX running Vista via Boot Camp (hey, I like lots of OS's m'kay?) When installing from Ubuntu software center my system very frequently freezes. This has happened 4 of the last 5 installs. Most recently I was installing the Google Earth .deb from Google's website: clicking the .deb file automatically opens Software Center (otherwise I would have used Synaptic, as I've grown to expect Software Center to freeze my system and I'm rather tired of it.) By "freeze" I mean nothing works: no dash, no launcher, no mouse movement, no alt-tab, can't open terminal (keyboard does not work). Software center does show the "installing" icon but after that it greys out and I can't click anything. REISUB has no effect but a cold power-down and restart is possible. Occasionally, after 5-10 minutes, I'll be able to move the mouse / use the keyboard and run a launcher command or two, although other open apps (Chrome and Software Center) will still be greyed-out/frozen. (I've never waited longer than that - if still unresponsive after 15 minutes I just power down and restart.) Most recently, which is why I am finally posting a question, I waited about 15 minutes and was finally able to open System Monitor while this was going on. Processes tells me that System Monitor is using about 20% of CPU, and nothing else is using much (zeros mostly). In fact I didn't even see Software Center listed? However at this point the system finally partially unfroze, the installation completed, and while I wasn't about to close Software Center I was able to do a system shutdown and fresh restart and I went and took a look at the syslog. In /var/log/syslog I see a lot of ":blocked for more than 120 seconds" messages. Similar to ubuntu hang out with this message :blocked for more than 120 seconds Which has not been answered, and I'm not running a virtual machine. My full syslog with stack traces looks very, very similar to this: Why do tasks on Amazon Xen instance block for over 120 seconds causing server to hang? Note that that question was solved, but that's because the problem was being caused by Amazon and Amazon fixed the bug. I'm not running anything Amazon-related. My syslog does look very similar, however. My question is also similar to this: Troubleshooting server hang But the referenced "duplicate" in that question is about how to kill processes/restart when the system freezes. I know how to kill processes and restart. I want to figure out what is causing the problem so I can try to fix it. I realize that I could just use Synaptic instead of Ubuntu Software Center, but I'd like to try to solve the problem if possible. I'm thinking I should perhaps submit a bug report, but I wanted to first see if anyone else was having any similar problems, and if so what you all did to fix it. I see a number of questions about Software Center freezing and others, including those I linked, about the "blocked for more than 120 seconds" log error, but I didn't see any question that links the two. I did save a copy of the syslog report if anyone wants to see it, but as mentioned it's quite similar to the one posted in the Amazon-related question...and I didn't want to take up even more space unnecessarily as, my apologies - this question has already become extremely verbose!

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• List of common pages to have in the footer [closed]

  - by user359650

  I would like to post this question as a reference for webmasters wondering what pages they should include in the footer. I will use answers to complete my initial list: About us / About MyCompany / MyCompany About / About us: description about the company, its mission, and its vision. History: summary of milestones achieved by the company. The team / Management / Board of directors: depending on size of the company there may be one of more pages describing the people involved in the company, depending on their position. Awards: list of awards received by the company if any. In the press / They're talking about us: list of links to external websites, usually highly regarded news websites, which mentioned the company in one of their articles. Media Wallpapers: wallpapers with company logo in different colors and formats that fans can set as desktop image for their computer. logos: company logo in different colors and formats that websites/blogs posting about the website can use for illustration purposes. Media kits: documents, usually in PDF format summarizing the key company figures and facts that journalists can download and read to get a quick overview of the company. Misc Contact / Contact us: contact details the company is prepared to disclose if any (address, email, phone) or contact form. Careers / Jobs / Join us: list of open vacancies with contact form to apply. Investors / Partners / Publishers: information and contact forms for companies willing to become Investors/Partners/Publishers or login page to access portal restricted to those who already are. FAQ: list of common questions and answers to guide users and reduce number of support requests. Follow us / Community Facebook / Twitter / Google+: links to the company's pages/accounts on various social networks. Legal Terms / Terms of use / Terms & Conditions: rules users must follow when browsing the website. Privacy / Privacy Statement: explanations as to how the company deals with users' personal data and what users can do about it (request information to be deleted...). cookies: page that starts appearing on more and more websites due to new regulation (notably EU) imposing more transparency and control for users about cookies (e.g. BBC cookie page). Any input is welcome PS: if someone with enough rep could add the footer tag that would be great (min. 300 required).

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• BlockingCollection having issues with byte arrays

  - by MJLaukala

  I am having an issue where an object with a byte[20] is being passed into a BlockingCollection on one thread and another thread returning the object with a byte[0] using BlockingCollection.Take(). I think this is a threading issue but I do not know where or why this is happening considering that BlockingCollection is a concurrent collection. Sometimes on thread2, myclass2.mybytes equals byte[0]. Any information on how to fix this is greatly appreciated. MessageBuffer.cs public class MessageBuffer : BlockingCollection<Message> { } In the class that has Listener() and ReceivedMessageHandler(object messageProcessor) private MessageBuffer RecievedMessageBuffer; On Thread1 private void Listener() { while (this.IsListening) { try { Message message = Message.ReadMessage(this.Stream, this); if (message != null) { this.RecievedMessageBuffer.Add(message); } } catch (IOException ex) { if (!this.Client.Connected) { this.OnDisconnected(); } else { Logger.LogException(ex.ToString()); this.OnDisconnected(); } } catch (Exception ex) { Logger.LogException(ex.ToString()); this.OnDisconnected(); } } } Message.ReadMessage(NetworkStream stream, iTcpConnectClient client) public static Message ReadMessage(NetworkStream stream, iTcpConnectClient client) { int ClassType = -1; Message message = null; try { ClassType = stream.ReadByte(); if (ClassType == -1) { return null; } if (!Message.IDTOCLASS.ContainsKey((byte)ClassType)) { throw new IOException("Class type not found"); } message = Message.GetNewMessage((byte)ClassType); message.Client = client; message.ReadData(stream); if (message.Buffer.Length < message.MessageSize + Message.HeaderSize) { return null; } } catch (IOException ex) { Logger.LogException(ex.ToString()); throw ex; } catch (Exception ex) { Logger.LogException(ex.ToString()); //throw ex; } return message; } On Thread2 private void ReceivedMessageHandler(object messageProcessor) { if (messageProcessor != null) { while (this.IsListening) { Message message = this.RecievedMessageBuffer.Take(); message.Reconstruct(); message.HandleMessage(messageProcessor); } } else { while (this.IsListening) { Message message = this.RecievedMessageBuffer.Take(); message.Reconstruct(); message.HandleMessage(); } } } PlayerStateMessage.cs public class PlayerStateMessage : Message { public GameObject PlayerState; public override int MessageSize { get { return 12; } } public PlayerStateMessage() : base() { this.PlayerState = new GameObject(); } public PlayerStateMessage(GameObject playerState) { this.PlayerState = playerState; } public override void Reconstruct() { this.PlayerState.Poisiton = this.GetVector2FromBuffer(0); this.PlayerState.Rotation = this.GetFloatFromBuffer(8); base.Reconstruct(); } public override void Deconstruct() { this.CreateBuffer(); this.AddToBuffer(this.PlayerState.Poisiton, 0); this.AddToBuffer(this.PlayerState.Rotation, 8); base.Deconstruct(); } public override void HandleMessage(object messageProcessor) { ((MessageProcessor)messageProcessor).ProcessPlayerStateMessage(this); } } Message.GetVector2FromBuffer(int bufferlocation) This is where the exception is thrown because this.Buffer is byte[0] when it should be byte[20]. public Vector2 GetVector2FromBuffer(int bufferlocation) { return new Vector2( BitConverter.ToSingle(this.Buffer, Message.HeaderSize + bufferlocation), BitConverter.ToSingle(this.Buffer, Message.HeaderSize + bufferlocation + 4)); }

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• Criminals and Other Illegal Characters

  - by Most Valuable Yak (Rob Volk)

  SQLTeam's favorite Slovenian blogger Mladen (b | t) had an interesting question on Twitter: http://www.twitter.com/MladenPrajdic/status/347057950470307841 I liked Kendal Van Dyke's (b | t) reply: http://twitter.com/SQLDBA/status/347058908801667072 And he was right!  This is one of those pretty-useless-but-sounds-interesting propositions that I've based all my presentations on, and most of my blog posts. If you read all the replies you'll see a lot of good suggestions.  I particularly like Aaron Bertrand's (b | t) idea of going into the Unicode character set, since there are over 65,000 characters available.  But how to find an illegal character?  Detective work? I'm working on the premise that if SQL Server will reject it as a name it would throw an error.  So all we have to do is generate all Unicode characters, rename a database with that character, and catch any errors. It turns out that dynamic SQL can lend a hand here: IF DB_ID(N'a') IS NULL CREATE DATABASE [a]; DECLARE @c INT=1, @sql NVARCHAR(MAX)=N'', @err NVARCHAR(MAX)=N''; WHILE @c<65536 BEGIN BEGIN TRY SET @sql=N'alter database ' + QUOTENAME(CASE WHEN @c=1 THEN N'a' ELSE NCHAR(@c-1) END) + N' modify name=' + QUOTENAME(NCHAR(@c)); RAISERROR(N'*** Trying %d',10,1,@c) WITH NOWAIT; EXEC(@sql); SET @c+=1; END TRY BEGIN CATCH SET @err=ERROR_MESSAGE(); RAISERROR(N'Ooops - %d - %s',10,1,@c,@err) WITH NOWAIT; BREAK; END CATCH END SET @sql=N'alter database ' + QUOTENAME(NCHAR(@c-1)) + N' modify name=[a]'; EXEC(@sql); The script creates a dummy database "a" if it doesn't already exist, and only tests single characters as a database name.  If you have databases with single character names then you shouldn't run this on that server. It takes a few minutes to run, but if you do you'll see that no errors are thrown for any of the characters.  It seems that SQL Server will accept any character, no matter where they're from.  (Well, there's one, but I won't tell you which. Actually there's 2, but one of them requires some deep existential thinking.) The output is also interesting, as quite a few codes do some weird things there.  I'm pretty sure it's due to the font used in SSMS for the messages output window, not all characters are available.  If you run it using the SQLCMD utility, and use the -o switch to output to a file, and -u for Unicode output, you can open the file in Notepad or another text editor and see the whole thing. I'm not sure what character I'd recommend to answer Mladen's question.  I think the standard tab (ASCII 9) is fine.  There's also several specific separator characters in the original ASCII character set (decimal 28-31). But of all the choices available in Unicode whitespace, I think my favorite would be the Mongolian Vowel Separator.  Or maybe the zero-width space. (that'll be fun to print!)  And since this is Mladen we're talking about, here's a good selection of "intriguing" characters he could use.

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• Hierachies....from the Top Down

  - by Joe G

  I've been struggling with how to write on the topic of the importance of hierarchy design.  It's not so much that hierarchies haven't always been important, it's more of that with Fusion, the timing of when the hierarchies are designed should take a higher priority.    I will attempt to explain..... When I was implementing applications, back in the day, we had the list of detailed account values to enter with the obvious parent accounts. Then, after the setup was complete and things were functioning, the reporting phase started.  Users explained the elements that they want on the reports, what totals should be included, and how things should be compared.  Frequently, there was at least one calculation that became a nightmare either because it was based on very specific things that didn't relate to anything else or because it was "hardcoded" so that when something changed, someone need to "fix" the report. With Fusion, the process changes slightly.  You still want to enter all of the detailed accounts, but before you start adding parent values, you should investigate the reporting requirements from the top-down.  It's better to build hierarchies based on the reporting requirements than it is to build reports based on random hierarchies. Build reports based on hierarchies that resemble the reports themselves, and maintain the hierarchies without rework of the reports. For example, if you look at an income statement, you may have line items for Material Costs, Employee Costs, Travel & Entertainment, and Total Operating Expenses.  In your hierarchy, you have detail values that roll up to Material Costs, Employee Costs, and Travel & Entertainment which roll up to Total Operating Expenses. Balances are stored automatically in the cube for each of these.  When you define the report, you pick each of these members - no calculations required.  If a new detail value is added, you simply add it to the hierarchy, and there is no need to modify the report. I realize that there are always exceptions that require special handling, but I am confident that you will end up with much fewer exceptions if you make reporting a priority and design your hierarchies from the top-down.

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• HOW TO: Change Internet Expenses Cost Center Prompt

  - by rveliche

  The cost center segment on the General Information page in Oracle Internet Expenses derives its label from the Prompt entered on the KFF setup. Changing this is not possible with the simple personalization, the details below provide the instructions to change the Prompt. Create a custom class, I call it CustomHeaderKffCO.java in the package oracle.apps.ap.oie.entry.header.webui  (or any other). This class will have to extend from oracle.apps.ap.oie.entry.header.webui.HeaderKffCO. Add the following logic to your custom class. package oracle.apps.ap.oie.entry.header.webui; import oracle.apps.fnd.framework.webui.OAPageContext; import oracle.apps.fnd.framework.webui.beans.OAWebBean; import oracle.apps.fnd.framework.webui.beans.message.OAMessageLayoutBean; import oracle.apps.fnd.framework.webui.OAControllerImpl; public class CustomHeaderKffCO extends HeaderKffCO {   public void processRequest(OAPageContext pageContext, OAWebBean webBean)   {      super.processRequest(pageContext, webBean);     OAMessageLayoutBean layoutBean = (OAMessageLayoutBean) webBean.findChildRecursive("KffSEGMENT2MessageLayout");    if(layoutBean != null)   {     // You should use messages/lookups to avoid translation issues.     layoutBean.setLabel("Cost Center");   }   } } KffSEGMENT2MessageLayout is for illustration only, my Chart Of Accounts has SEGMENT2 as the cost center segment. Please change this to a segment being used eg.Segment6 should be KFFSEGMENT6MessageLayout Note that super.processRequest(pageContext, webBean); is a must and should always be the first statement. Once the class is compiled, copy the class to an appropriate directory, in my case I used $JAVA_TOP/oracle/apps/ap/oie/entry/header/webui. Navigate to the General Information page, click on "Personalize General Information Page".Click on Personalize icon next to Message Component Layout: (OIEGeneralInformationMsgCLayout)In the controller class section update the new controller at the appropriate levelIf the Link "Personalize General Information Page" is not visible on your instance, check your personalization profiles.

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• How to use multiple search keys?

  - by user32565

  I have a database wherein the files are named abcd100.00b, abcd101.00b, etc. I need a code where when the user enters abcd separate then 100 to 110, all the files with the name abcd and in the range 100 to 110 should get displayed now the following code can display only the first four characters. How do I implement this? <?php //capture search term and remove spaces at its both ends if the is any $searchTerm = trim($_GET['keyname']) ; //check whether the name parsed is empty if($searchTerm == "rinex_file") { echo "Enter name you are searching for."; exit(); } if($searchTerm == "rinex_file") { echo "Enter name you are searching for."; exit(); } //database connection info $host = "localhost"; //server $db = "rinex"; //database name $user = "m"; //dabases user name $pwd = "c"; //password //connecting to server and creating link to database $link = mysqli_connect($host, $user, $pwd, $db); //MYSQL search statement $query = "SELECT * FROM rinexo WHERE rinex_file LIKE '%$searchTerm%'"; $results = mysqli_query($link, $query) ; /* check whethere there were matching records in the table by counting the number of results returned */ if(mysqli_num_rows($results) >= 1){ echo '<table border="1"> <tr> <th>rinex version</th> <th>program</th> <th>date</th> <th>maker name</th> <th>maker number</th> <th>observer</th> <th>agency</th> <th>position_X_Y_Z</th> </tr>'; while($row = mysqli_fetch_array($results)){ echo '<tr> <td>'.$row['rinex_version'].'</td> <td>'.$row['pgm'].'</td> <td>'.$row['date'].'</td> <td>'.$row['marker_name'].'</td> <td>'.$row['marker_no'].'</td> <td>'.$row['observer'].'</td> <td>'.$row['agency'].'</td> <td>'.$row['position_X_Y_Z'].'</td> </tr>'; } echo '</table>'; }else{ echo "There was no matching record for the name " . $searchTerm; }

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• Is this a pattern? Should it be?

  - by Arkadiy

  The following is more of a statement than a question - it describes something that may be a pattern. The question is: is this a known pattern? Or, if it's not, should it be? I've had a situation where I had to iterate over two dissimilar multi-layer data structures and copy information from one to the other. Depending on particular use case, I had around eight different kinds of layers, combined in about eight different combinations: A-B-C B-C A-C D-E A-D-E and so on After a few unsuccessful attempts to factor out the repetition of per-layer iteration code, I realized that the key difficulty in this refactoring was the fact that the bottom level needed access to data gathered at higher levels. To explicitly accommodate this requirement, I introduced IterationContext class with a number of get() and set() methods for accumulating the necessary information. In the end, I had the following class structure: class Iterator { virtual void iterateOver(const Structure &dataStructure1, IterationContext &ctx) const = 0; }; class RecursingIterator : public Iterator { RecursingIterator(const Iterator &below); }; class IterateOverA : public RecursingIterator { virtual void iterateOver(const Structure &dataStructure1, IterationContext &ctx) const { // Iterate over members in dataStructure1 // locate corresponding item in dataStructure2 (passed via context) // and set it in the context // invoke the sub-iterator }; class IterateOverB : public RecursingIterator { virtual void iterateOver(const Structure &dataStructure1, IterationContext &ctx) const { // iterate over members dataStructure2 (form context) // set dataStructure2's item in the context // locate corresponding item in dataStructure2 (passed via context) // invoke the sub-iterator }; void main() { class FinalCopy : public Iterator { virtual void iterateOver(const Structure &dataStructure1, IterationContext &ctx) const { // copy data from structure 1 to structure 2 in the context, // using some data from higher levels as needed } } IterationContext ctx(dateStructure2); IterateOverA(IterateOverB(FinalCopy())).iterate(dataStructure1, ctx); } It so happens that dataStructure1 is a uniform data structure, similar to XML DOM in that respect, while dataStructure2 is a legacy data structure made of various structs and arrays. This allows me to pass dataStructure1 outside of the context for convenience. In general, either side of the iteration or both sides may be passed via context, as convenient. The key situation points are: complicated code that needs to be invoked in "layers", with multiple combinations of layer types possible at the bottom layer, the information from top layers needs to be visible. The key implementation points are: use of context class to access the data from all levels of iteration complicated iteration code encapsulated in implementation of pure virtual function two interfaces - one aware of underlying iterator, one not aware of it. use of const & to simplify the usage syntax.

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• Unintentional run-in with C# thread concurrency

  - by geekrutherford

  For the first time today we began conducting load testing on a ASP.NET application already in production. Obviously you would normally want to load test prior to releasing to a production environment, but that isn't the point here.   We ran a test which simulated 5 users hitting the application doing the same actions simultaneously. The first few pages visited seemed fine and then things just hung for a while before the test failed. While the test was running I was viewing the performance counters on the server noting that the CPU was consistently pegged at 100% until the testing tool gave up.   Fortunately the application logs all exceptions including those unhandled to the database (thanks to log4net). I checked the log and low and behold the error was:   System.ArgumentException: An item with the same key has already been added. (The rest of the stack trace intentionally omitted)   Since the code was running with debug on the line number where the exception occured was also provided. I began inspecting the code and almost immediately it hit me, the section of code responsible for the exception is trying to initialize a static class. My next question was how is this code being hit multiple times when I have a rudimentary check already in place to prevent this kind of thing (i.e. a check on a public variable of the static class before entering the initializing routine). The answer...the check fails because the value is not set before other threads have already made it through.   Not being one who consistently works with threading I wasn't quite sure how to handle this problem. Fortunately a co-worker recalled having to lock a section of code in the past but couldn't recall exactly how. After a quick search on Google the solution is as follows:   Object objLock = new Object(); lock(objLock) { //logic requiring lock }   The lock statement takes an object and tells the .NET runtime that the current thread has exclusive access while the code within brackets is executing. Once the code completes, the lock is released for another thread to utilize.   In my case, I only need to execute the inner code once to initialize my static class. So within the brackets I have a check on a public variable to prevent it from being initialized again.

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