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  • Static Logger in seperate thread?

    - by SirLenz0rlot
    Hi all, I've made my Logger, that logs a string, a static class with a static so I can call it from my entire project without having to make an instance of it. quite nice, but I want to make it run in a seperate thread, since accessing the file costs time is that possible somehow and what's the best way to do it? Its a bit of a short discription, but I hope the idea is clear. if not, please let me know. Thanks in advance! btw: any other improvements on my code are welcome as well, i have the feeling not everthing is as efficient as it can be: internal static class MainLogger { internal static void LogStringToFile(string logText) { DateTime timestamp = DateTime.Now; string str = timestamp.ToString("dd-MM-yy HH:mm:ss ", CultureInfo.InvariantCulture) + "\t" + logText + "\n"; const string filename = Constants.LOG_FILENAME; FileInfo fileInfo = new FileInfo(filename); if (fileInfo.Exists) { if (fileInfo.Length > Constants.LOG_FILESIZE) { File.Create(filename).Dispose(); } } else { File.Create(filename).Dispose(); } int i = 0; while(true) { try { using (StreamWriter writer = File.AppendText(filename)) { writer.WriteLine(str); } break; } catch (IOException) { Thread.Sleep(10); i++; if (i >= 8) { throw new IOException("Log file \"" + Constants.LOG_FILENAME + "\" not accessible after 5 tries"); } } } } } enter code here

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  • Move SELECT to SQL Server side

    - by noober
    Hello all, I have an SQLCLR trigger. It contains a large and messy SELECT inside, with parts like: (CASE WHEN EXISTS(SELECT * FROM INSERTED I WHERE I.ID = R.ID) THEN '1' ELSE '0' END) AS IsUpdated -- Is selected row just added? as well as JOINs etc. I like to have the result as a single table with all included. Question 1. Can I move this SELECT to SQL Server side? If yes, how to do this? Saying "move", I mean to create a stored procedure or something else that can be executed before reading dataset in while cycle. The 2 following questions make sense only if answer is "yes". Why do I want to move SELECT? First off, I don't like mixing SQL with C# code. At second, I suppose that server-side queries run faster, since the server have more chances to cache them. Question 2. Am I right? Is it some sort of optimizing? Also, the SELECT contains constant strings, but they are localizable. For instance, WHERE R.Status = "Enabled" "Enabled" should be changed for French, German etc. So, I want to write 2 static methods -- OnCreate and OnDestroy -- then mark them as stored procedures. When registering/unregistering my assembly on server side, just call them respectively. In OnCreate format the SELECT string, replacing {0}, {1}... with required values from the assembly resources. Then I can localize resources only, not every script. Question 3. Is it good idea? Is there an existing attribute to mark methods to be executed by SQL Server automatically after (un)registartion an assembly? Regards,

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  • Short snippet summarizing a webpage?

    - by Legend
    Is there a clean way of grabbing the first few lines of a given link that summarizes that link? I have seen this being done in some online bookmarking applications but have no clue on how they were implemented. For instance, if I give this link, I should be able to get a summary which is roughly like: I'll admit it, I was intimidated by MapReduce. I'd tried to read explanations of it, but even the wonderful Joel Spolsky left me scratching my head. So I plowed ahead trying to build decent pipelines to process massive amounts of data Nothing complex at first sight but grabbing these is the challenging part. Just the first few lines of the actual post should be fine. Should I just use a raw approach of grabbing the entire html and parsing the meta tags or something fancy like that (which obviously and unfortunately is not generalizable to every link out there) or is there a smarter way to achieve this? Any suggestions? Update: I just found InstaPaper do this but am not sure if it is getting the information from RSS feeds or some other way.

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  • xsl defining in xml

    - by aditya parikh
    My first few lines in movies.xml are as follows : <?xml version="1.0" encoding="ISO-8859-1"?> <?xml-stylesheet type="text/xsl" href="movies_style.xsl"?> <movies xmlns="http://www.w3schools.com" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://www.w3schools.com file:///B:/USC/Academic/DBMS/HWS/no3/movie_sch.xsd"> and first few lines in movies_style.xsl are as follows : <?xml version="1.0" encoding="UTF-8"?> <xsl:stylesheet version="1.0" xmlns:xsl="http://www.w3.org/1999/XSL/Transform" xmlns:fo="http://www.w3.org/1999/XSL/Format"> Problem is if remove schema file linking from movies.xml file and keep tag only as <movies> then proper styled table is shown as output else nothing is displayed in browser and error is displayed in console as: "Unsafe attempt to load URL file:///B:/USC/Academic/DBMS/HWS/no3/movies_style.xsl from frame with URL file:///B:/USC/Academic/DBMS/HWS/no3/movies.xml. Domains, protocols and ports must match." Looks like some namespace mistake. Can anyone point out exactly what ?

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  • Is there really such a thing as "being good at math"?

    - by thezhaba
    Aside from gifted individuals able to perform complex calculations in their head, I'm wondering if proficiency in mathematics, namely calculus and algebra, has really got to do with one's natural inclination towards sciences, if you can put it that way. A number of students in my calculus course pick up material in seemingly no time whereas I, personally, have to spend time thinking about and understanding most concepts. Even then, if a question that requires a bit more 'imagination' comes up I don't always recognize the concepts behind it, as is the case with calculus proofs, for instance. Nevertheless, I refuse to believe that I'm simply not made for it. I do very well in programming and software engineering courses where a lot of students struggle. At first I could not grasp what they found to be so difficult, but eventually I realized that having previous programming experience is a great asset -- once I've seen and made practical use of the programming concepts learning about them in depth in an academic setting became much easier as I have then already seen their use "in the wild". I suppose I'm hoping that something similar happens with mathematics -- perhaps once the practical idea behind a concept (which authors of textbooks sure do a great job of concealing..) is evident, understanding the seemingly dry and symbolic ideas and proofs would be more obvious? I'm really not sure. All I'm sure of is I'd like to get better at calculus, but I don't yet understand why some of us pick it up easily while others have to spend considerable amounts of time on it and still not have complete understanding if an unusual problem is given.

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  • How does one force construction of a global object in a statically linked library? [MSVC9]

    - by Peter C O Johansson
    I have a global list of function pointers. This list should be populated at startup. Order is not important and there are no dependencies that would complicate static initialization. To facilitate this, I've written a class that adds a single entry to this list in its constructor, and scatter global instances of this class via a macro where necessary. One of the primary goals of this approach is to remove the need for explicitly referencing every instance of this class externally, instead allowing each file that needs to register something in the list to do it independently. Nice and clean. However, when placing these objects in a static library, the linker discards (or rather never links in) these units because no code in them is explicitly referenced. Explicitly referencing symbols in the compilation units would be counterproductive, directly contradicting one of the main goals of the approach. For the same reason, /INCLUDE is not an acceptable option, and /OPT:NOREF is not actually related to this problem. Metrowerks has a __declspec directive for it, GCC has -force_load, but I cannot find any equivalent for MSVC.

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  • Problem with generic list and extension method(C#3.0)

    - by Newbie
    I have an issue. I am making an extension class for a Collection and it is generic.. like public static class ListExtensions { public static ICollection<T> Search<T>(this ICollection<T> collection, string stringToSearch) { ICollection<T> t1=null; foreach (T t in collection) { Type k = t.GetType(); PropertyInfo pi = k.GetProperty("Name"); if (pi.GetValue(t,null).Equals(stringToSearch)) { t1.Add(t); } } return t1; } } But I cannot add items to t1 as it is declared null. Error: object reference not set to an instance of the object. I am calling the method like List<TestClass> listTC = new List<TestClass>(); listTC.Add(new TestClass { Name = "Ishu", Age = 21 }); listTC.Add(new TestClass { Name = "Vivek", Age = 40 }); listTC.Add(new TestClass { Name = "some one else", Age = 12 }); listTC.Search("Ishu"); And the test class is public class TestClass { public string Name { get; set; } public int Age { get; set; } } Using : (C#3.0) & Framework - 3.5 Thanks

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  • How do I get require_login()-like functionality using the new PHP Client Library for Facebook?

    - by cc
    Howdy. I've been tasked with making a Facebook game, but I'm new to Facebook development, so I'm just getting started. Apologies in advance if this is a no-brainer to people. I'm having trouble following all the examples I see on sites, and I keep running into missing pages in the Facebook documentation when I am trying to read up. I think it's because there's a new version of the PHP Client Library for Facebook, and everything I'm finding is referring to the old client. For instance, I see this code in a lot of examples: require 'facebook.php'; $facebook = new Facebook( array( 'appId' => '(id)', 'secret' => '(secret)' ) ); $facebook_account = $facebook->require_login(); ...but there's no "require_login()" in the client library provided in the facebook.php file. From what I can tell, it looks like Facebook has very recently rolled out some new system for development, but I don't see any sample code anywhere to deal with it. The new library comes with an "example.php" file, but it appears to be only for adding "Log in with Facebook" functionality to other sites (what I'm assuming is what they mean by "Facebook Connect" sites), not for just running apps in a Canvas page on Facebook itself. Specifically, what I need to do is let users visit an application page within Facebook, have it bring up the dialog box allowing them to authorize the app, have it show up in their "games" page, and then have it pass me the relevant info about the user so I can start creating the game. But I can't seem to find any tutorials or examples that show how to do this using the new library. Seems like this should be pretty straightforward, but I'm running into roadblocks. Or am I missing something about the PHP client library? Should require_login() be working for me, and there's something broken with my implementation, such as having the wrong client library or something? I downloaded from GitHub yesterday, so I'm pretty sure I have the most recent version of the code I have, but perhaps I'm downloading the wrong "facebook.php" file...?

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  • OOP design issue: Polymorphism

    - by Graham Phillips
    I'm trying to solve a design issue using inheritance based polymorphism and dynamic binding. I have an abstract superclass and two subclasses. The superclass contains common behaviour. SubClassA and SubClassB define some different methods: SubClassA defines a method performTransform(), but SubClassB does not. So the following example 1 var v:SuperClass; 2 var b:SubClassB = new SubClassB(); 3 v = b; 4 v.performTransform(); would cause a compile error on line 4 as performTransform() is not defined in the superclass. We can get it to compile by casting... (v as SubClassA).performTransform(); however, this will cause a runtime exception to be thrown as v is actually an instance of SubClassB, which also does not define performTransform() So we can get around that by testing the type of an object before casting it: if( typeof v == SubClassA) { (cast v to SubClassA).performTransform(); } That will ensure that we only call performTransform() on v's that are instances of SubClassA. That's a pretty inelegant solution to my eyes, but at least its safe. I have used interface based polymorphism (interface meaning a type that can't be instantiated and defines the API of classes that implement it) in the past, but that also feels clunky. For the above case, if SubClassA and SubClassB implemented ISuperClass that defined performTransform, then they would both have to implement performTransform(). If SubClassB had no real need for a performTransform() you would have to implement an empty function. There must be a design pattern out there that addresses the issue.

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  • How to catch unintentional function interpositioning?

    - by SiegeX
    Reading through my book Expert C Programming, I came across the chapter on function interpositioning and how it can lead to some serious hard to find bugs if done unintentionally. The example given in the book is the following: my_source.c mktemp() { ... } main() { mktemp(); getwd(); } libc mktemp(){ ... } getwd(){ ...; mktemp(); ... } According to the book, what happens in main() is that mktemp() (a standard C library function) is interposed by the implementation in my_source.c. Although having main() call my implementation of mktemp() is intended behavior, having getwd() (another C library function) also call my implementation of mktemp() is not. Apparently, this example was a real life bug that existed in SunOS 4.0.3's version of lpr. The book goes on to explain the fix was to add the keyword static to the definition of mktemp() in my_source.c; although changing the name altogether should have fixed this problem as well. This chapter leaves me with some unresolved questions that I hope you guys could answer: Does GCC have a way to warn about function interposition? We certainly don't ever intend on this happening and I'd like to know about it if it does. Should our software group adopt the practice of putting the keyword static in front of all functions that we don't want to be exposed? Can interposition happen with functions introduced by static libraries? Thanks for the help. EDIT I should note that my question is not just aimed at interposing over standard C library functions, but also functions contained in other libraries, perhaps 3rd party, perhaps ones created in-house. Essentially, I want to catch any instance of interpositioning regardless of where the interposed function resides.

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  • Running Cargo From Maven antrun Plugin

    - by Frank
    I have a maven (multi-module) project creating some WAR and EAR files for JBoss AS 7.1.x. For one purpose, I need to deploy one generated EAR file of one module to a fresh JBoss instance and run it, call some REST web service calls against it and stop JBoss. Then I need to package the results of these calls that were written to the database. Currently, I am trying to use CARGO and the maven ant run plugin to perform this task. Unfortunately, I cannot get the three (maven, ant run and CARGO) to play together. I don't have the uberjar that is used in the ant examples of cargo. How can I configure the ant run task so that the cargo ant task can create, start, deploy my JBoss? Ideally the one unpacked and configured by the cargo-maven2-plugin in another phase? Or, is there a better way to achieve my goal of creating the database? I cannot really use the integration-test phase, as it is executed after the package phase. So, I plan to do it all in compile phase using antrun.

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  • Querying the size of a drive on a remote server is giving me an error

    - by Testifier
    Here's what I have: public static bool DriveHasLessThanTenPercentFreeSpace(string server) { long driveSize = 0; long freeSpace = 0; var oConn = new ConnectionOptions {Username = "username", Password = Settings.Default.SQLServerAdminPassword}; var scope = new ManagementScope("\\\\" + server + "\\root\\CIMV2", oConn); //connect to the scope scope.Connect(); //construct the query var query = new ObjectQuery("SELECT FreeSpace FROM Win32_LogicalDisk where DeviceID = 'D:'"); //this class retrieves the collection of objects returned by the query var searcher = new ManagementObjectSearcher(scope, query); //this is similar to using a data adapter to fill a data set - use an instance of the ManagementObjectSearcher to get the collection from the query and store it ManagementObjectCollection queryCollection = searcher.Get(); //iterate through the object collection and get what you're looking for - in my case I want the FreeSpace of the D drive foreach (ManagementObject m in queryCollection) { //the FreeSpace value is in bytes freeSpace = Convert.ToInt64(m["FreeSpace"]); //error happens here! driveSize = Convert.ToInt64(m["Size"]); } long percentFree = ((freeSpace / driveSize) * 100); if (percentFree < 10) { return true; } return false; } This line of code is giving me an error: driveSize = Convert.ToInt64(m["Size"]); The error says: ManagementException was unhandled by user code Not found I'm assuming the query to get the drive size is wrong. Please note that I AM getting the freeSpace value at the line: freeSpace = Convert.ToInt64(m["FreeSpace"]); So I know the query IS working for freeSpace. Can anyone give me a hand?

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  • I need an IDE for typo3 core development in php

    - by Flugan
    Php in itself is difficult for IDEs because of the dynamic nature of the language. My current development environment is mostly netbeans against a local svn copy of the codebase setup in a local development webserver. The code is full text indexed by vistas search engine for almost instant searches. I do a lot of development directly against the main development server using a combination of tools. Putty to interact with the server and deploy by updating an svn checkout on the development server. Tortoise SVN locally to have a fairly rich SVN experience. Netbeans obviously have SVN integration. Most of the changes on the remote server is commited using the putty session. WinSCP to interact with the development server with norton commander like interface as well as the good putty integration. Finally my text editor for remote editing is notepad++ out of habit and because of some nice features and good price. What I'm really missing is good php editing. Because of the way typo3 works almost all objects are instanciated through make instance abstraction that either returns the base class or the customized class if the framework has been extended. I'm not looking for a magic editing package and would like to find an editor which can use annotations to specify the type of commonly used variables.

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  • Can't store UTF-8 in RDS despite setting up new Parameter Group using Rails on Heroku

    - by Lail
    I'm setting up a new instance of a Rails(2.3.5) app on Heroku using Amazon RDS as the database. I'd like to use UTF-8 for everything. Since RDS isn't UTF-8 by default, I set up a new Parameter Group and switched the database to use that one, basically per this. Seems to have worked: SHOW VARIABLES LIKE '%character%'; character_set_client utf8 character_set_connection utf8 character_set_database utf8 character_set_filesystem binary character_set_results utf8 character_set_server utf8 character_set_system utf8 character_sets_dir /rdsdbbin/mysql-5.1.50.R3/share/mysql/charsets/ Furthermore, I've successfully setup Heroku to use the RDS database. After rake db:migrate, everything looks good: CREATE TABLE `comments` ( `id` int(11) NOT NULL AUTO_INCREMENT, `commentable_id` int(11) DEFAULT NULL, `parent_id` int(11) DEFAULT NULL, `content` text COLLATE utf8_unicode_ci, `child_count` int(11) DEFAULT '0', `created_at` datetime DEFAULT NULL, `updated_at` datetime DEFAULT NULL, PRIMARY KEY (`id`), KEY `commentable_id` (`commentable_id`), KEY `index_comments_on_community_id` (`community_id`), KEY `parent_id` (`parent_id`) ) ENGINE=InnoDB AUTO_INCREMENT=4 DEFAULT CHARSET=utf8 COLLATE=utf8_unicode_ci; In the markup, I've included: <meta http-equiv="Content-Type" content="text/html; charset=utf-8" /> Also, I've set: production: encoding: utf8 collation: utf8_general_ci ...in the database.yml, though I'm not very confident that anything is being done to honor any of those settings in this case, as Heroku seems to be doing its own config when connecting to RDS. Now, I enter a comment through the form in the app: "Úbe® ƒåiL", but in the database I've got "Úbe® Æ’Ã¥iL" It looks fine when Rails loads it back out of the database and it is rendered to the page, so whatever it is doing one way, it's undoing the other way. If I look at the RDS database in Sequel Pro, it looks fine if I set the encoding to "UTF-8 Unicode via Latin 1". So it seems Latin-1 is sneaking in there somewhere. Somebody must have done this before, right? What am I missing?

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  • How is an AppDelegate instanciated?

    - by pwny
    I have an iOS application for which I want to create a ViewController programmatically. I started an empty XCode project and modified the main method so it looks like this int main(int argc, char *argv[]) { NSAutoreleasePool *pool = [[NSAutoreleasePool alloc] init]; int retVal = UIApplicationMain(argc, argv, nil, @"MyAppDelegate_iPad"); [pool release]; return retVal; } The app is a Universal Application, MyAppDelegate_iPad is a subclass of MyAppDelegate, which is a subclass of NSObject <UIApplicationDelegate>. My problem is that the applicationDidFinishLoading method I've overridden in MyAppDelegate_iPad is never called (break point on the first line never hits). The method looks like this -(void) applicationDidFinishLaunching:(UIApplication *)application { window = [[UIWindow alloc] initWithFrame:[[UIScreen mainScreen] bounds]]; if(!window) { [self release]; return; } window.backgroundColor = [UIColor whiteColor]; rootController = [[MyViewController alloc] init]; [window addSubview:rootController.view]; [window makeKeyAndVisible]; [window layoutSubviews]; } I removed the line to link to a nib file from my plist file (I used to get the default "My Universal app on iPad" white screen) and now all that is displayed is a black screen. applicationDidFinishLoading is still not being called. Am I doing something wrong? How should I properly create my AppDelegate instance?

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  • Stuck trying to get Log4Net to work with Dependency Injection

    - by Pure.Krome
    I've got a simple winform test app i'm using to try some Log4Net Dependency Injection stuff. I've made a simple interface in my Services project :- public interface ILogging { void Debug(string message); // snip the other's. } Then my concrete type will be using Log4Net... public class Log4NetLogging : ILogging { private static ILog Log4Net { get { return LogManager.GetLogger( MethodBase.GetCurrentMethod().DeclaringType); } } public void Debug(string message) { if (Log4Net.IsDebugEnabled) { Log4Net.Debug(message); } } } So far so good. Nothing too hard there. Now, in a different project (and therefore namesapce), I try and use this ... public partial class Form1 : Form { public Form1() { FileInfo fileInfo = new FileInfo("Log4Net.config"); log4net.Config.XmlConfigurator.Configure(fileInfo); } private void Foo() { // This would be handled with DI, but i've not set it up // (on the constructor, in this code example). ILogging logging = new Log4NetLogging(); logging.Debug("Test message"); } } Ok .. also pretty simple. I've hardcoded the ILogging instance but that is usually dependency injected via the constructor. Anyways, when i check this line of code... return LogManager.GetLogger(MethodBase.GetCurrentMethod().DeclaringType); the DeclaringType type value is of the Service namespace, not the type of the Form (ie. X.Y.Z.Form1) which actually called the method. Without passing the type INTO method as another argument, is there anyway using reflection to figure out the real method that called it?

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  • how to handle empty selection in a jface bound combobox?

    - by guido
    I am developing a search dialog in my eclipse-rcp application. In the search dialog I have a combobox as follows: comboImp = new CCombo(grpColSpet, SWT.BORDER | SWT.READ_ONLY); comboImp.setBounds(556, 46, 184, 27); comboImpViewer = new ComboViewer(comboImp); comboImpViewer.setContentProvider(new ArrayContentProvider()); comboImpViewer.setInput(ImpContentProvider.getInstance().getImps()); comboImpViewer.setLabelProvider(new LabelProvider() { @Override public String getText(Object element) { return ((Imp)element).getImpName(); } }); Imp is a database entity, ManyToOne to the main entity which is searched, and ImpContentProvider is the model class which speaks to embedded sqlite database via jpa/hibernate. This combobox is supposed to contain all instances of Imp, but to also let empty selection; it's value is bound to a service bean as follows: IObservableValue comboImpSelectionObserveWidget = ViewersObservables.observeSingleSelection(comboImpViewer); IObservableValue filterByImpObserveValue = BeansObservables.observeValue(searchPrep, "imp"); bindingContext.bindValue(comboImpSelectionObserveWidget, filterByImpObserveValue , null, null); As soon as the user clicks on the combo, a selection (first element) is made: I can see the call to a selectionlistener i added on the viewer. My question is: after a selection has been made, how do I let the user change his mind and have an empty selection in the combobox? should I add a "fake" empty instance of Imp to the List returned by the ImpContentProvider? or should I implement an alternative to ArrayContentProvider? and one additional related question is: why calling deselectAll() and clearSelection() on the combo does NOT set a null value to the bound bean?

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  • What changed in the DataGrid that means it won't work anymore?

    - by Jeff Yates
    I have a Silverlight app with a DataGrid containing some custom columns and all was working well. Then I updated to Silverlight 3 tools for VS 2008 SP1 and rebuilt it. Now it has the following problems: Rows aren't added when the collection is modified. The ItemsSource property is (and always has been) set to an ObservableCollection instance, which notifies when its contents change. This worked fine for Silverlight 2. However, in Silverlight 3 to get this working at all, I now have to null and then re-set ItemsSource - this seems like I'm hiding a bigger issue but I can't work out what that might be. I cannot select a row or a cell anymore. If I'm lucky, I can select one whole row before it stops working. I can't edit anything. I suspect this is related to the previous point. I'll post some source when I am able, but first I have to strip it down to the bare minimum. In the meantime, I was hoping someone might have some idea of what may be going on here. My gut feeling on the second two points is that my bindings are no longer working, but that's just a guess and if it is the case, I have no idea which ones. Thanks for any help anyone might be able to provide. Update So, I finally reduced my problem down to a simple works/doesn't work comparison. The problem seems to occur if I override Equals in my element type. As soon as I do that, something happens strangely in the ObservableCollection that contains that type, it seems, and my application breaks. To make it more interesting, there is a check to make sure that duplicate items don't even get close to being added to the collection. I don't exactly know why ObservableCollection needs to compare equality when inserting items (the stack trace indicates it is using IndexAt) but this seems to cause the issue. So, any thoughts?

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  • `enable_shared_from_this` has a non-virtual destructor

    - by Shtééf
    I have a pet project with which I experiment with new features of the upcoming C++0x standard. While I have experience with C, I'm fairly new to C++. To train myself into best practices, (besides reading a lot), I have enabled some strict compiler parameters (using GCC 4.4.1): -std=c++0x -Werror -Wall -Winline -Weffc++ -pedantic-errors This has worked fine for me. Until now, I have been able to resolve all obstacles. However, I have a need for enable_shared_from_this, and this is causing me problems. I get the following warning (error, in my case) when compiling my code (probably triggered by -Weffc++): base class ‘class std::enable_shared_from_this<Package>’ has a non-virtual destructor So basically, I'm a bit bugged by this implementation of enable_shared_from_this, because: A destructor of a class that is intended for subclassing should always be virtual, IMHO. The destructor is empty, why have it at all? I can't imagine anyone would want to delete their instance by reference to enable_shared_from_this. But I'm looking for ways to deal with this, so my question is really, is there a proper way to deal with this? And: am I correct in thinking that this destructor is bogus, or is there a real purpose to it?

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  • CREATE VIEW called multiple times not creating all views

    - by theninepoundhammer
    Noticing strange behavior in SQL 2005, both Express and Enterprise Edition: In my code I need to loop through a series of values (about five in a row), and for each value, I need to insert the value into a table and dynamically create a new view using that value as part of the where clause and the name of the view. The code runs pretty quickly, but what I'm noticing is that all the values are inserted into the table correctly but only the LAST view is being created. Every time. For example, if the values I'm using are X1, X2, X3, X4, and X5, I'll run the process, open up Mgmt Studio, and see five rows in the table with the correct five values, but only one view named MyView_x5 that has the correct WHERE clause. At first, I had this loop in an SSIS package as part of a larger data flow. When I started noticing this behavior, I created a stored proc that would create the CREATE VIEW statement dynamically after the insert and called EXECUTE to create the view. Same result. Finally, I created some C# code using the Enterprise Library DAAB, and did the insert and CREATE VIEW statements from my DLL. Same result every time. Most recently, I turned on Profiler while running against the Enterprise Edition and was able to verify that the Batch Started and Batch Completed events were being fired off for each instance of the view. However, like I said, only the last view is actually being created. Does anyone have any idea why this might be happening? Or any suggestions about what else to check or profile? I've profiled for error messages, exceptions, etc. but don't see any in my trace file. My express edition is 9.00.1399.06. Not sure about the Enterprise edition but think it is SP2.

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  • Using static variables for Strings

    - by Vivart
    below content is taken from Best practice: Writing efficient code but i didn't understand why private static String x = "example"; faster than private static final String x ="example"; Can anybody explain this. Using static variables for Strings When you define static fields (also called class fields) of type String, you can increase application speed by using static variables (not final) instead of constants (final). The opposite is true for primitive data types, such as int. For example, you might create a String object as follows: private static final String x = "example"; For this static constant (denoted by the final keyword), each time that you use the constant, a temporary String instance is created. The compiler eliminates "x" and replaces it with the string "example" in the bytecode, so that the BlackBerry® Java® Virtual Machine performs a hash table lookup each time that you reference "x". In contrast, for a static variable (no final keyword), the String is created once. The BlackBerry JVM performs the hash table lookup only when it initializes "x", so access is faster. private static String x = "example"; You can use public constants (that is, final fields), but you must mark variables as private.

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  • unexpected behaviour of object stored in web service Session

    - by draconis
    Hi. I'm using Session variables inside a web service to maintain state between successive method calls by an external application called QBWC. I set this up by decorating my web service methods with this attribute: [WebMethod(EnableSession = true)] I'm using the Session variable to store an instance of a custom object called QueueManager. The QueueManager has a property called ChangeQueue which looks like this: [Serializable] public class QueueManager { ... public Queue<QBChange> ChangeQueue { get; set; } ... where QBChange is a custom business object belonging to my web service. Now, every time I get a call to a method in my web service, I use this code to retrieve my QueueManager object and access my queue: QueueManager qm = (QueueManager)Session[ticket]; then I remove an object from the queue, using qm.dequeue() and then I save the modified query manager object (modified because it contains one less object in the queue) back to the Session variable, like so: Session[ticket] = qm; ready for the next web service method call using the same ticket. Now here's the thing: if I comment out this last line //Session[ticket] = qm; , then the web service behaves exactly the same way, reducing the size of the queue between method calls. Now why is that? The web service seems to be updating a class contained in serialized form in a Session variable without being asked to. Why would it do that? When I deserialize my Queuemanager object, does the qm variable hold a reference to the serialized object inside the Session[ticket] variable?? This seems very unlikely.

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  • jQuery: Adding li element only if it not already there?

    - by Legend
    I am constructing an <li> element like this: var element = $("<li></li>") .html(mHTML) .attr('id', "elemid"); I am trying to add this element to a <ul> element only if it doesn't already exist. Any ideas on how to do this? Am I supposed to use contains() to see if the ul element contain the html and then decide? For instance, <ul id="elemul"> <li id="elemli1">Element 1</li> <li id="elemli2">Element 2</li> <li id="elemli3">Element 3</li> </ul> If I try adding Element 1, it should not add it. What should I do if its a longer string (not really long but about 150 characters). Do I go about using hashmaps?

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  • Linq-to-XML explicit casting in a generic method

    - by vlad
    I've looked for a similar question, but the only one that was close didn't help me in the end. I have an XML file that looks like this: <Fields> <Field name="abc" value="2011-01-01" /> <Field name="xyz" value="" /> <Field name="tuv" value="123.456" /> </Fields> I'm trying to use Linq-to-XML to get the values from these fields. The values can be of type Decimal, DateTime, String and Int32. I was able to get the fields one by one using a relatively simple query. For example, I'm getting the 'value' from the field with the name 'abc' using the following: private DateTime GetValueFromAttribute(IEnumerable<XElement> fields, String attName) { return (from field in fields where field.Attribute("name").Value == "abc" select (DateTime)field.Attribute("value")).FirstOrDefault() } this is placed in a separate function that simply returns this value, and everything works fine (since I know that there is only one element with the name attribute set to 'abc'). however, since I have to do this for decimals and integers and dates, I was wondering if I can make a generic function that works in all cases. this is where I got stuck. here's what I have so far: private T GetValueFromAttribute<T>(IEnumerable<XElement> fields, String attName) { return (from field in fields where field.Attribute("name").Value == attName select (T)field.Attribute("value").Value).FirstOrDefault(); } this doesn't compile because it doesn't know how to convert from String to T. I tried boxing and unboxing (i.e. select (T) (Object) field.Attribute("value").Value but that throws a runtime Specified cast is not valid exception as it's trying to convert the String to a DateTime, for instance. Is this possible in a generic function? can I put a constraint on the generic function to make it work? or do I have to have separate functions to take advantage of Linq-to-XML's explicit cast operators?

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  • Dynamic use of :default_url in Paperclip

    - by dgilperez
    I'm trying to configure Paperclip to provide different missing images based on the instance's category attribute. Every category of the object has its own missing image. This is my first take: EDIT to add full models: class Service < ActiveRecord::Base attr_accessible :logo, :logo_file_name, :logo_content_type, :logo_file_size, :logo_updated_at belongs_to :category, :counter_cache => true has_attached_file :logo, :path => "/:id-:style-:filename", :url => ":s3_eu_url", :default_url => "/logos/:style/#{self.category.name]}.png", :styles => { :large => "600x400>", :medium => "300x200>", :small => "100x75>", :thumb => "60x42>" } end class Category < ActiveRecord::Base attr_accessible nil has_many :services end In my view, image_tag service.logo.url(:thumb) outputs: undefined method `category' for #<Class:0x0000010a731620> Any ideas? EDIT2: A working default_url is :default_url => "/logos/:style/missing.png", SOLUTION: See my own answer below.

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