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  • System.ServiceModel.Channels.MessageHeader Error

    - by user220511
    I'm trying to get the following to work on my machine but I get an error (Cannot create an instance of the abstract class or interface 'System.ServiceModel.Channels.MessageHeader') using System; using System.IO; using System.Reflection; namespace com.mycompanyname.business { /// /// Summary description for SessionCreateRQClient. /// class SessionCreateRQClient { /// /// The main entry point. /// [STAThread] static void Main(string[] args) { try { // Set user information, including security credentials and the IPCC. string username = "user"; string password = "password"; string ipcc = "IPCC"; string domain = "DEFAULT"; string temp = Environment.GetEnvironmentVariable("tmp"); // Get temp directory string PropsFileName = temp + "/session.properties"; // Define dir and file name DateTime dt = DateTime.UtcNow; string tstamp = dt.ToString("s") + "Z"; //Create the message header and provide the conversation ID. MessageHeader msgHeader = new MessageHeader(); msgHeader.ConversationId = "TestSession"; // Set the ConversationId From from = new From(); PartyId fromPartyId = new PartyId(); PartyId[] fromPartyIdArr = new PartyId[1]; fromPartyId.Value = "WebServiceClient"; fromPartyIdArr[0] = fromPartyId; from.PartyId = fromPartyIdArr; msgHeader.From = from; To to = new To(); PartyId toPartyId = new PartyId(); PartyId[] toPartyIdArr = new PartyId[1]; toPartyId.Value = "WebServiceSupplier"; toPartyIdArr[0] = toPartyId; to.PartyId = toPartyIdArr; msgHeader.To = to; //Add the value for eb:CPAId, which is the IPCC. //Add the value for the action code of this Web service, SessionCreateRQ. msgHeader.CPAId = ipcc; msgHeader.Action = "SessionCreateRQ"; Service service = new Service(); service.Value = "SessionCreate"; msgHeader.Service = service; MessageData msgData = new MessageData(); msgData.MessageId = "mid:[email protected]"; msgData.Timestamp = tstamp; msgHeader.MessageData = msgData; Security security = new Security(); SecurityUsernameToken securityUserToken = new SecurityUsernameToken(); securityUserToken.Username = username; securityUserToken.Password = password; securityUserToken.Organization = ipcc; securityUserToken.Domain = domain; security.UsernameToken = securityUserToken; SessionCreateRQ req = new SessionCreateRQ(); SessionCreateRQPOS pos = new SessionCreateRQPOS(); SessionCreateRQPOSSource source = new SessionCreateRQPOSSource(); source.PseudoCityCode = ipcc; pos.Source = source; req.POS = pos; SessionCreateRQService serviceObj = new SessionCreateRQService(); serviceObj.MessageHeaderValue = msgHeader; serviceObj.SecurityValue = security; SessionCreateRS resp = serviceObj.SessionCreateRQ(req); // Send the request if (resp.Errors != null && resp.Errors.Error != null) { Console.WriteLine("Error : " + resp.Errors.Error.ErrorInfo.Message); } else { msgHeader = serviceObj.MessageHeaderValue; security = serviceObj.SecurityValue; Console.WriteLine("**********************************************"); Console.WriteLine("Response of SessionCreateRQ service"); Console.WriteLine("BinarySecurityToken returned : " + security.BinarySecurityToken); Console.WriteLine("**********************************************"); string ConvIdLine = "convid="+msgHeader.ConversationId; // ConversationId to a string string TokenLine = "securitytoken="+security.BinarySecurityToken; // BinarySecurityToken to a string string ipccLine = "ipcc="+ipcc; // IPCC to a string File.Delete(PropsFileName); // Clean up TextWriter tw = new StreamWriter(PropsFileName); // Create & open the file tw.WriteLine(DateTime.Now); // Write the date for reference tw.WriteLine(TokenLine); // Write the BinarySecurityToken tw.WriteLine(ConvIdLine); // Write the ConversationId tw.WriteLine(ipccLine); // Write the IPCC tw.Close(); //Console.Read(); } } catch(Exception e) { Console.WriteLine("Exception Message : " + e.Message ); Console.WriteLine("Exception Stack Trace : " + e.StackTrace); Console.Read(); } } } } I have added the reference System.ServiceModel and the lines: using System.ServiceModel; using System.ServiceModel.Channels; but I continue to get that error when trying to compile -- "Cannot create an instance of the abstract class or interface 'System.ServiceModel.Channels.MessageHeader'" I am using Microsoft Visual Studio 2008 Version 9.0.21022.8 RTM Microsoft .NET Framework Version 3.5 SP1 Professional Edition Is there another reference I have to add? Or a dll to move over? I wonder was the code above written for Framework 2.0 only? Thanks for your help.

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  • Does Qt support virtual pure slots ?

    - by ereOn
    Hi, My GUI project in Qt has a lot of "configuration pages" classes which all inherit directly from QWidget. Recently, I realized that all these classes share 2 commons slots (loadSettings() and saveSettings()). Regarding this, I have two questions: Does it make sense to write a intermediate base abstract class (lets name it BaseConfigurationPage) with these two slots as virtual pure methods ? (Every possible configuration page will always have these two methods, so I would say "yes") Before I do the heavy change in my code (if I have to) : does Qt support virtual pure slots ? Is there anything I should be aware of ? Here is a code example describing everything: class BaseConfigurationPage : public QWidget { // Some constructor and other methods, irrelevant here. public slots: virtual void loadSettings() = 0; virtual void saveSettings() = 0; }; class GeneralConfigurationPage : public BaseConfigurationPage { // Some constructor and other methods, irrelevant here. public slots: void loadSettings(); void saveSettings(); };

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  • NHibernate: discriminator without common base class?

    - by joniba
    Is it possible to map two classes to the same property without them sharing a common base class? For example, a situation like this: class Rule { public virtual int SequenceNumber { get; set; } public virtual ICondition Condition { get; set; } } interface ICondition { } class ExpressionCondition : ICondition { public virtual string Expression { get; set; } } class ThresholdCondition : ICondition { public virtual int Threshold { get; set; } } I also cannot add some empty abstract class that both conditions inherit from because the two ICondition implementations exist in different domains that are not allowed to reference each other. (Please no responses telling me that this situation should not occur in the first place - I'm aware of it and it doesn't help me.)

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  • Is it possible to create nested classes in PHP as it is in C#?

    - by Edward Tanguay
    In C# you can have nested classes like this, which are useful if you have classes which do not have meaning outside the scope of one particular class, e.g. in a factory pattern: public abstract class BankAccount { private BankAccount() {} private sealed class SavingsAccount : BankAccount { ... } private sealed class CheckingAccount : BankAccount { ... } public BankAccount MakeSavingAccount() { ... } public BankAccount MakeCheckingAccount() { ... } } Is this possible in PHP? I've read that it was planned for PHP 5, then cancelled, then planned again, but can't find definitive info. Does anyone know how to create nested classes (classes within the scope of another class) as in the above C# example using PHP 5.3?

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  • Example of contravariance

    - by Misha
    I am thinking of the following example to illustrate why contravariance is useful. Let's consider a GUI framework with Widgets, Events, and Event Listeners. abstract class Event; class KeyEvent extends Event class MouseEvent extends Event trait EventListener[-Event] { def listen(e:Event) } Let Widgets define the following methods: def addKeyEventListener(listener:EventListener[KeyEvent]) def addMouseEventListener(listener:EventListener[MouseEvent]) These methods accept only "specific" event listeners, which is fine. However I would like to define also "kitchen-sink" listeners, which listen to all events, and pass such listeners to the "add listener" methods above. For instance, I would like to define LogEventListener to log all incoming events class LogEventListener extends EventListener[Event] { def listen(e:Event) { log(event) } } Since the trait EventListener is contravariant in Event we can pass LogEventListener to all those "add listener" methods without losing their type safety. Does it make sense ?

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  • Questions about my program and Polymorphism

    - by Strobe_
    Ok, so basically I'm creating a program which allows the user to select a shape (triangle, square, circle) and then it takes in a int and calculates the boundary length and area. I have no problem doing this and have a program that's working perfectly. (https://gist.github.com/anonymous/c63a03c129560a7b7434 4 classes) But now I have to implement this with polymorphism concepts and I'm honestly struggling as to how to do it. I have a basic idea of what I want to do when it comes to inheritance Main | Shapes / | \ triangle circle square But I don't understand how I'm supposed to override when all the methods within the triangle/square/circle classes are unique, there are no "abstract" methods as such that I could inherit from the "Shapes" class. If somebody could make look quickly at the code I linked and suggest a way to do this it would be much appreciated. Sorry if I was bad at explaining this. Thanks.

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  • Question about domain models & their visibility...

    - by Another SO User
    I was involved in an interesting debate about the visibility of domain models & was wondering if people here have any good guidance. Per my understanding of MDA, we need not expose the domain model throughout the application layers & tiers The reason being that any change to the domain model has an impact in the overall application The wise thing to do would be to expose light-weight object (DTO's) which are a small sub-set of the domain model to abstract the actual model On the flip side, any change to the domain model would mean changing various DTO's throughout the application for the change to be visible, while if we do expose the domain model, then the change is in a single location Hope to see some comments & thoughts about this. Appreciate all the help!

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  • Rails architecture questions

    - by justinbach
    I'm building a Rails site that, among other things, allows users to build their own recipe repository. Recipes are entered either manually or via a link to another site (think epicurious, cooks.com, etc). I'm writing scripts that will scrape a recipe from these sites given a link from a user, and so far (legal issues notwithstanding) that part isn't giving me any trouble. However, I'm not sure where to put the code that I'm writing for these scraper scripts. My first thought was to put it in the recipes model, but it seems a bit too involved to go there; would a library or a helper be more appropriate? Also, as I mentioned, I'm building several different scrapers for different food websites. It seems to me that the elegant way to do this would be to define an interface (or abstract base class) that determines a set of methods for constructing a recipe object given a link, but I'm not sure what the best approach would be here, either. How might I build out these OO relationships, and where should the code go?

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  • Trust metrics and related algorithms

    - by Nick Gerakines
    I'm trying to learn more about trust metrics (including related algorithms) and how user voting, ranking and rating systems can be wired to stiffle abuse. I've read abstract articles and papers describing trust metrics but haven't seen any actual implementations. My goal is to create a system that allows users to vote on other users and the content of other users and with those votes and related meta-data, determine if those votes can be applied to a users level or popularity. Have you used or seen some sort of trust system within a social graph? How did it work and what were its areas of strength and weaknesses?

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  • how to use multiple $_name using extends Zend_Db_Table_Abstract in zend frame work.

    - by karthik
    we tried to give our tables(users,messages) like this in two different abstract classes but it is not working. This is included in a file childconnect1.php ,is there any relation between the file name(childconnect1.php) and the class(Application_Model_childconnect1). class Application_Model_childconnect1 extends Zend_Db_Table_Abstract { protected $_name = 'users'; public function loginvalidation($username,$pwd) { $row = $this->fetchRow('UserName = \'' . $username . '\'and UserPW = \''. $pwd . '\''); if (!$row) { $msg="invalid"; return $msg; } else { return $row->toArray(); } } } class Application_Model_childconnect2 extends Zend_Db_Table_Abstract { protected $_name = 'messages'; public function replymessage($message) { $data=array( 'MessageText'=>$message ); $this->insert($data); } }

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  • JVM specification and Java compiler code useful for SCJP preparation ?

    - by BenoitParis
    I'm preparing the SCJP exam with the almost official study book ("SCJP Sun Certified Programmer for Java 6 Exam 310-065") I understand that Java programming is writting code that fulfills a certain high-level contract; So that Java can stay platform-independent. However, I have trouble understanding and remembering things when it comes to highly specific SCJP items (and they are numerous) The book stays high-level and does not provide examples of how one compiler would handle things. This is the same thing for runtime issues (JVM level): things are too much abstract for me. Rules often seems arbitrary and therefore, with no well defined purpose, are difficult to remember. Or maybe it's that sometimes I just don't get the underlying purpose. And here is the question: Would a JVM specification and/or some java compiler code help in preparing the SCJP? Have you had the need for such material or is the book sufficient enough? Also, please share the resources you used, apart from the book.

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  • Consequences in PHP of implementing an interface through two different routes?

    - by Daniel Bingham
    What are the consequences of implementing the same interface through two different routes in PHP, are there any? What I mean, is something like this: interface baseInterface {} abstract class baseClass implements baseInterface { } interface myInterface extends baseInterface {} class myClass extends baseClass implements myInterface {} In this case myClass implements baseInterface from two different parents - myInterface and baseClass. Are there any consequences to this? My instinct is that PHP should handle this fine, but I just want to make sure. What exactly does PHP do in this case? Does it just check to see that the necessary functions are implemented for the interface each time it discovers it and call it a day or does it do something more?

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  • Is concatenating with an empty string to do a string conversion really that bad?

    - by polygenelubricants
    Let's say I have two char variables, and later on I want to concatenate them into a string. This is how I would do it: char c1, c2; // ... String s = "" + c1 + c2; I've seen people who say that the "" + "trick" is "ugly", etc, and that you should use String.valueOf or Character.toString instead. I prefer this construct because: I prefer using language feature instead of API call if possible In general, isn't the language usually more stable than the API? If language feature only hides API call, then even stronger reason to prefer it! More abstract! Hiding is good! I like that the c1 and c2 are visually on the same level String.valueOf(c1) + c2 suggests something is special about c1 It's shorter. Is there really a good argument why String.valueOf or Character.toString is preferrable to "" +? Trivia: in java.lang.AssertionError, the following line appears 7 times, each with a different type: this("" + detailMessage);

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  • What real life bad habits has programming given you? [closed]

    - by Jacob T. Nielsen
    Programming has given me a lot of bad habits and it continues to give me more everyday. But I have also gotten some bad habits from the mindset that I have put myself in. There simply are some things that are deeply rooted in my nature, though some of them I wish I could get rid of. A few: Looking for polymorphism, inheritance and patterns in all of God's creations. Explaining the size of something in pixels and colors in hex code. Using code related abstract terms in everyday conversations. How have you been damaged?

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  • Returning a static array without using a class field

    - by Bart Friederichs
    I have the following base and derived (partial, for sake of brevity) classes: class Base { public abstract int[] someArray { get; } } class Derived : Base { private readonly static int[] _someArray = new int[] { 1,2,3,4 }; public override int[] someArray { get { return _someArray; } } } What I would like now, is put the new int[] { 1,2,3,4 } in the return part of the getter. But, that would create a new array every time the getter is called. Is it possible to directly return some kind of object, which stays the same for all objects of class Derived ? Something along the lines of (I know this is invalid C#): get { return (int[]) { 1, 2, 3, 4 }; }

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  • gwt - Using List<Serializable> in a RPC call?

    - by Garagos
    I have a RPC service with the following method: public List<Serializable> myMethod(TransactionCall call) {...} But I get a warning when this method is analyzed, and then the rpc call fails Analyzing 'my.project.package.myService' for serializable types Analyzing methods: public abstract java.util.List<java.io.Serializable> myMethod(my.project.package.TransactionCall call) Return type: java.util.List<java.io.Serializable> [...] java.io.Serializable Verifying instantiability (!) Checking all subtypes of Object wich qualify for serialization It seems I can't use Serializable for my List... I could use my own interface instead (something like AsyncDataInterface, wich implements the Serializable interface) but the fact is that my method will return a list custom objects AND basic objects (such as Strings, int....). So my questions are: Is it a standart behaviour? (I can't figure out why I can't use this interface in that case) Does anyone have a workaround for that kind of situation?

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  • Java cannot find symbol enum

    - by JDelage
    Hi, I'm modeling a chess game on Java, and I'm having some problem. Here's what the code looks like (the relevant parts): Enum class Couleur.java: public enum Couleur {BLANC, NOIR} Piece.java: public abstract class Piece { (...) public Piece(Couleur couleurParam){ this.couleurPiece = couleurParam; } (...) } And finally Tour.java: public class Tour extends Piece { (...) public Tour(Couleur couleurParam){ super(couleurParam); } (...) } All the .java files are in the same folder. Yet at compile I get a "cannot find symbol symbol : variable NOIR location: class Plateau" (Plateau is the class that instantiates Tour.) Can anyone help me figure out what's wrong here? Many thanks, JDelage

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  • How to overload shutdown function?

    - by Michal M
    I am using Kohana (v3) framework but I believe it's not tied to a particular framework. What I have is basically an app with a front-end, where I want to use Kohana's native Kohana::shutdown_handler(), but I also have a part of the - RESTful API - where I don't want colourful and html-encoded exception reporting. I want a plain text reporting. The way I thought it might work is to register another shutdown function in API's controller abstract class constructor, but then I realised register_shutdown_function() works differently to set_exception_handler() and instead of replacing it adds another function to the shutdown procedure. What's worse PHP doesn't allow "unregistering" shutdown functions and that's where my problem lies. What to do, if you want to use another shutdown function instead of one already registered?

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  • Unit Testing: hard dependency MessageBox.Show()

    - by Sean B
    What ways can the SampleConfirmationDialog be unit tested? The SampleConfirmationDialog would be exercised via acceptance tests, however how could we unit test it, seeing as MessageBox is not abstract and no matching interface? public interface IConfirmationDialog { /// <summary> /// Confirms the dialog with the user /// </summary> /// <returns>True if confirmed, false if not, null if cancelled</returns> bool? Confirm(); } /// <summary> /// Implementation of a confirmation dialog /// </summary> public class SampleConfirmationDialog : IConfirmationDialog { /// <summary> /// Confirms the dialog with the user /// </summary> /// <returns>True if confirmed, false if not, null if cancelled</returns> public bool? Confirm() { return MessageBox.Show("do operation x?", "title", MessageBoxButton.YesNo, MessageBoxImage.Question) == MessageBoxResult.Yes; } }

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  • WCF interoperability with WSDL proxy and performance consideration advise.

    - by user194917
    I'm essentially writing a broker service. The requirement is that I write an API that acts as an intermediary broker between our in-house developed services and a 3rd party provided API. The intention being that my API abstract the actual communication with the 3rd party API from our internal systems. The architect on the project chose WCF as the communication framework. The problem is that 70 percent of our subscriber applications are written in .Net 2 and as such have no access to the class libraries required to implement a WCF proxy. The end result being that our proxy classes are loosely based on the code auto generated by the WSDL tool as opposed to the SvcUtil tool. My question is, although I have no issues implementing the required proxy classes using basicHttp as the actual binding and using the WSDL tool, are there any special considerations that I need to take into account in this scenario? I.E proxy optimizations and the like. Thanks in advance.

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  • using partials in view helpers

    - by takeshin
    Creating custom Zend View helpers I often end up with something like: // logic here if ($condition) { $output = <<<EOS... } else { $output = <<<EOS... } or using switch. Then to eliminate this, I create setPartial(), getPartial() and htmlize() for using external .phtml's. This is not the best solution, because partials do not support doctype changing. Is there any better solution, than creating abstract class handling this common case? Are there any ready Zend solutions for this case? Separate view helper for each case? And where to put common code?

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  • Programming tutorials for people with zero experience

    - by www.aegisub.net
    A friend of mine is interested in learning how to program computers, but she knows nothing about programming. I suggested that Python might be a good language to start with, but after some googling, I couldn't find any tutorials that covered both programming and Python in an adequate way. I don't want her to go through the tiresome "learn algorithms in pseudocode first" routine. Instead, I'd like a tutorial that will explain the basic ideas while working towards a real goal, e.g. a very simple console game. Does anyone know of any such tutorials? Do you think that I'm mistaken in how I'm handling this? Is Python a bad choice? I know that something like C, C++ or Java won't work - too many details will be very counterproductive. On the other hand, I think that Lisp might be too mathematical and abstract. Python, on the other hand, will let her even do something like coding primitive graphical games in a short period of time.

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  • Why Is It That Generics Constraint Can't Be Casted to Its Derived Type?

    - by Ngu Soon Hui
    It is quite puzzling to find out that Generics Constraint Can't Be Casted to Its Derived Type. Let's say I have the following code: public abstract class BaseClass { public int Version { get { return 1; } } public string FixString { get; set; } public BaseClass() { FixString = "hello"; } public virtual int GetBaseVersion() { return Version; } } public class DeriveClass: BaseClass { public new int Version { get { return 2; } } } And guess what, this method will return a compilation error: public void FreeConversion<T>(T baseClass) { var derivedMe = (DeriveClass)baseClass; } I would have to cast the baseClass to object first before I can cast it to DerivedClass. Seems to me pretty ugly. Why this is so?

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  • Inheriting database connection in PHP OOP

    - by vrode
    My abstract class Database is made for database interaction and any child of this class (UserDatabase, ActionDatabase, EventDatabase) inherits its database connection which is defined as static. `abstract class Database { static $connection = mysql_connect( ); } class UserDatabase extends Database { ... public function __construct( ) { $connection ? "connected" : "not connected"; $this-table = "users"; mysql_query( "FROM " . $this-table . " SELECT *" ); } } ` Does that mean, that my database connection is only set up and stored in memory once and passed on to subclasses as reference without being replicated for each instance? Is this how you would implement you OOP-correct database interface?

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  • Programming Quiz [closed]

    - by arin-s-rizk
    Hi one of my mates sent me this quiz see if you can guess the answers I will post mine later. In this quiz, some tasks related to the compilation process are listed. For each one of them, specify the part of the compiler that is responsible of performing it. Here are the possible answers: Lexical analyzer Parser Semantic analyzer None of the above Just fill the right choice (the number only) in the blank after each task: Checking that the parentheses in an expression are balanced _ _ _ _ _ Removing comments from the program _ _ _ _ _ Grouping input characters into "tokens" _ _ _ _ _ Reporting an error to the programmer about a missing (;) at the end of a C++ statement _ _ _ _ _ Checking if the type of the RHS (Right-Hand Side) of an assignment (=) is compatible with the LHS (Left-Hand Side) variable _ _ _ _ _ Converting the (AST) Abstract Syntax Tree into machine language _ _ _ _ _ Reporting an error about a strange character like '^' in a C++ program _ _ _ _ _ Optimizing the AST _ _ _ _ _

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