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  • Forget late static binding, I need late static __FILE__ ...

    - by bobthecow
    I'm looking for the get_called_class() equivalent for __FILE__ ... Maybe something like get_included_file()? I have a set of classes which would like to know what directory they exist in. Something like this: <?php class A { protected $baseDir; public function __construct() { $this->baseDir = dirname(__FILE__); } public function getBaseDir() { return $this->baseDir; } } ?> And in some other file, in some other folder... <?php class B extends A { // ... } class C extends B { // ... } $a = new A; echo $a->getBaseDir(); $b = new B; echo $b->getBaseDir(); $c = new C; echo $c->getBaseDir(); // Annnd... all three return the same base directory. ?> Now, I could do something ghetto, like adding $this->baseDir = dirname(__FILE__) to each and every extending class, but that seems a bit... ghetto. After all, we're talking about PHP 5.3, right? Isn't this supposed to be the future? Is there another way to get the path to the file where a class was declared?

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  • How do you make a private member in the base class become a public member in the base class?

    - by jasonline
    Consider the following code: class Base { void f() { } }; class Derived: public Base { public: }; What can you change in the derived class, such that you can perform the following: Derived d; d.f(); If the member is declared as public in the base class, adding a using declaration for Base::f in the derived class public section would've fix the problem. But if it is declared as private in the base class, this doesn't seem to work.

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  • Problem overridding virtual function

    - by William
    Okay, I'm writing a game that has a vector of a pairent class (enemy) that s going to be filled with children classes (goomba, koopa, boss1) and I need to make it so when I call update it calls the childclasses respective update. I have managed to create a example of my problem. #include <stdio.h> class A{ public: virtual void print(){printf("Hello from A");} }; class B : public A{ public: void print(){printf("Hello from B");} }; int main(){ A ab = B(); ab.print(); while(true){} } Output wanted: "Hello from B" Output got: "Hello from A" How do I get it to call B's print function?

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  • are there requirements for Struts setters beyond variable name matching?

    - by slk
    I have a model-driven Struts Web action: public class ModelDrivenAction<T extends Object> implements ModelDriven<T>, Preparable { protected Long id; protected T model; @Override public void prepare() {} public void setId(Long id) { this.id = id; } @Override public T getModel() { return model; } public void setModel(T model) { this.model = model; } } I have another action which is not currently model-driven: public class OtherAction implements Preparable { private ModelObj modelObj; private Long modelId; @Override public void prepare() { modelObj = repoService.retrieveModelById(modelId); } public void setModelId(Long modelId) { this.modelId = modelId; } } I wish to make it so, and would like to avoid having to track down all the instances in JavaScript where the action is passed a "modelId" parameter instead of "id" if at all possible. I thought this might work, so either modelId or id could be passed in: public class OtherAction extends ModelDrivenAction<ModelObj> { @Override public void prepare() { model = repoService.retrieveModelById(id); } public void setModelId(Long modelId) { this.id = modelId; } } However, server/path/to/other!method?modelId=123 is failing to set id. I thought so long as a setter matched a parameter name the Struts interceptor would call it on action invocation. Am I missing something here?

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  • How to save derived type (TPT) in Entity Framework?

    - by Peter Stegnar
    I have problems with saving derived type (TPT) with Entity Framework to database. Let's say I have base entity Animal and derived type Dog. I want to save Dog entity. I thought that I could do it like contex.AddToDogs(), but contex contain only base entity - Animal. So I can only save Animal object - contex.AddToAnimals(). I have also tried with contex.AddObject("Animals", dogInstance), but I get the following error: The member with identity 'NavigationProperty' does not exist in the metadata collection. But I have add EntityReference to the "NavigationProperty". So how to save derived type in EF?

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  • What is the best way to "override" enums?

    - by Tyler
    I have a number of classes which extend an abstract class. The abstract parent class defines an enum with a set of values. Some of the subclasses inherit the parent class's enum values, but some of the subclasses need the enum values to be different. Is there any way to somehow override the enum for these particular subclasses, and if not, what is a good way to achieve what I'm describing? class ParentClass { private MyEnum m_EnumVal; public virtual MyEnum EnumVal { get { return m_EnumVal; } set { m_EnumVal = value; } } public enum MyEnum { a, b, c }; } class ChildClass : ParentClass { private MyEnum m_EnumVal; public virtual MyEnum EnumVal { get { return m_EnumVal; } set { m_EnumVal = value; } } public enum MyEnum { d, e, f }; }

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  • Inheritence and usage of dynamic_cast

    - by Mewzer
    Hello, Suppose I have 3 classes as follows (as this is an example, it will not compile!): class Base { public: Base(){} virtual ~Base(){} virtual void DoSomething() = 0; virtual void DoSomethingElse() = 0; }; class Derived1 { public: Derived1(){} virtual ~Derived1(){} virtual void DoSomething(){ ... } virtual void DoSomethingElse(){ ... } virtual void SpecialD1DoSomething{ ... } }; class Derived2 { public: Derived2(){} virtual ~Derived2(){} virtual void DoSomething(){ ... } virtual void DoSomethingElse(){ ... } virtual void SpecialD2DoSomething{ ... } }; I want to create an instance of Derived1 or Derived2 depending on some setting that is not available until run-time. As I cannot determine the derived type until run-time, then do you think the following is bad practice?... class X { public: .... void GetConfigurationValue() { .... // Get configuration setting, I need a "Derived1" b = new Derived1(); // Now I want to call the special DoSomething for Derived1 (dynamic_cast<Derived1*>(b))->SpecialD1DoSomething(); } private: Base* b; }; I have generally read that usage of dynamic_cast is bad, but as I said, I don't know which type to create until run-time. Please help!

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  • ActiveRecord Validations for Models with has_many, belongs_to associations and STI

    - by keruilin
    I have four models: User Award Badge GameWeek The associations are as follows: User has many awards. Award belongs to user. Badge has many awards. Award belongs to badge. User has many game_weeks. GameWeek belongs to user. GameWeek has many awards. Award belongs to game_week. Thus, user_id, badge_id and game_week_id are foreign keys in awards table. Badge implements an STI model. Let's just say it has the following subclasses: BadgeA and BadgeB. Some rules to note: The game_week_id fk can be nil for BadgeA, but can't be nil for BadgeB. Here are my questions: For BadgeA, how do I write a validation that it can only be awarded one time? That is, the user can't have more than one -- ever. For BadgeB, how do I write a validation that it can only be awarded one time per game week?

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  • Generics and Derived Classes .NET 3.5

    - by Achilles
    Consider the following where class "Circle" inherits from "Shape": dim objListOfCircles as new List(of Circle) DrawShapes(objListOfCirlces) Private sub DrawShapes(byref objListOfShapes as List(of Shape)) for each objShape as Shape in objListOfShapes objShape.Draw() next end sub I can't get this to work. What is the explaination as to why this doesn't work?

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  • (Cocoa) Can I Subclass and Delegate at the same time?

    - by Alvin
    @interface ClassB <ClassADelegate> : ClassA id <ClassBDelegate> delegate; @end As the code says, ClassB subclasses from ClassA and handles the formation protocol of Class A. However, the variable "delegate" will be duplicated. (ClassA also has "delegate") In fact, it can be done without subclassing, but it seems the code is cumbersome, i.e., to use a variable/function of ClassA, I need to write [[ClassB classA] doSomething] instead of [classB doSomething], where doSomething: is a function of ClassA. Are there any tidy way for me to do that?

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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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  • Should downcasting be avoided while using a class hierarchy in C++?

    - by neuviemeporte
    Let's say I'm writing an application which works with projects, and exposes different functionality depending on the type of the project. I have a hierarchy of classes for the different types of projects: class AbstractProject { }; class ProjectA : public AbstractProject { }; class ProjectB : public AbstractProject { }; class ProjectC : public AbstractProject { }; Now, I was planning to have an AbstractProject *_currentProject pointer as a member in the application's main class, pop up a dialog box on startup and based on the selection, do: _currentProject = new ProjectB(); // e.g. Later, I'll have to downcast the pointer to the specific type to utilize the functionality specific to different Project-s. Somehow this makes me feel uneasy. Is there a Better Way of doing this?

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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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  • What would be a better implementation of shared variable among subclass

    - by Churk
    So currently I have a spring unit testing application. And it requires me to get a session cookie from a foreign authentication source. Problem what that is, this authentication process is fairly expensive and time consuming, and I am trying to create a structure where I am authenticate once, by any subclass, and any subsequent subclass is created, it will reuse this session cookie without hitting the authentication process again. My problem right now is, the static cookie is null each time another subclass is created. And I been reading that using static as a global variable is a bad idea, but I couldn't think of another way to do this because of Spring framework setting things during run time and how I would set the cookie so that all other classes can use it. Another piece of information. The variable is being use, but is change able during run time. It is not a single user being signed in and used across the board. But more like a Sub1 would call login, and we have a cookie. Then multiple test will be using that login until SubX will come in and say, I am using different credential, so I need to login as something else. And repeats. Here is a outline of my code: public class Parent implements InitializingBean { protected static String BASE_URL; public static Cookie cookie; ... All default InitializingBean methods ... afterPropertiesSet() { cookie = // login process returns a cookie } } public class Sub1 extends Parent { @resource public String baseURL; @PostConstruct public void init() { // set parents with my baseURL; BASE_URL = baseURL; } public void doSomething() { // Do something with cookie, because it should have been set by parent class } } public class Sub2 extends Parent { @resource public String baseURL; @PostConstruct public void init() { // set parents with my baseURL; BASE_URL = baseURL; } public void doSomethingElse() { // Do something with cookie, because it should have been set by parent class } }

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  • AS3: How can I require a method argument to implement multiple interfaces?

    - by Anders
    The argument to my method func() must implement the two unrelated interfaces IFoo and IBar. Is there a better way of doing this than declaring another interface only for this purpose that inherits from IFoo and IBar and using that interface as the argument type? public interface IFooBar implements IFoo, IBar { } public function func(arg:IFooBar):void { } I'm developing for Flash Player 9.

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  • question about class derivation in c++?

    - by jack22
    hi, i want to know some things about class derivation in c++ so i have super class x and an inherited class y and i did this class x{ public:a; private:b; protected:c; } class y:public x{ public:d; } in this case how y can access a,b,and c and by how i mean(public,protected,private) the second case: class x{ public:a; private:b; protected:c; } class y:private x{ public:d; } the same question? the third case: class x{ public:a; private:b; protected:c; } class y:private x{ public:d; } again the same question? sorry i think i wrote too much bye

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  • Compile time type determination in C++

    - by dicroce
    A coworker recently showed me some code that he found online. It appears to allow compile time determination of whether a type has an "is a" relationship with another type. I think this is totally awesome, but I have to admit that I'm clueless as to how this actually works. Can anyone explain this to me? template<typename BaseT, typename DerivedT> inline bool isRelated(const DerivedT&) { DerivedT derived(); char test(const BaseT&); // sizeof(test()) == sizeof(char) char (&test(...))[2]; // sizeof(test()) == sizeof(char[2]) struct conversion { enum { exists = (sizeof(test(derived())) == sizeof(char)) }; }; return conversion::exists; } Once this function is defined, you can use it like this: #include <iostream> class base {}; class derived : public base {}; class unrelated {}; int main() { base b; derived d; unrelated u; if( isRelated<base>( b ) ) std::cout << "b is related to base" << std::endl; if( isRelated<base>( d ) ) std::cout << "d is related to base" << std::endl; if( !isRelated<base>( u ) ) std::cout << "u is not related to base" << std::endl; }

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  • Unable to find assembly, C#

    - by PlasmaCube
    So, here's the deal. I've got two ASP.NET applications, both of which use SQLServer Session State management. They also both use the same server. I've got a custom session class in an external DLL, which fully implements serialization, and which both applications have referenced. Each application, in turn, has a class which inherits from the DLL class, and both applications use their own respective classes for their session state. Now, what I was trying to accomplish was that if you wanted to go to the other application, it could look in the session (they all use the same session key) and treat the existing object there as the base (the one from the DLL), extract whatever login info you need, then overwrite the session object with your own. Unfortunately, when the second application attempts to read the session, it seems that it looks for the DLL of the first application, and when it can't find it, it throws an exception. Is there a flaw in my logic? Here's an example: // Global.asax of the 1st app protected void Session_Start(object sender, EventArgs e) { Session.Add( "UserSessionKey", new FirstUserSession()); // FirstUserSession inherits from BaseUserSession } Now the second application: // Global.asax of 2nd app protected void Session_Start(object sender, EventArgs e) { if (Session["UserSessionKey"] != null) { BaseUserSession existing = (BaseUserSession)Session["UserSessionKey"]; SecondUserSession session = new SecondUserSession(); // This also inherits from BaseUserSession session.Authenticated = existing.Authenticated; session.Id = existing.Id; session.Role = existing.Role; Session.Add("UserSessionKey", session); } else { Session.Add("UserSessionKey", new SecondUserSession()); } } Here's the exception stack trace. In this case, "MyCBC" is the real name of the first app, and "ASPTesting" is the second app. [SerializationException: Unable to find assembly 'MyCBC, Version=1.0.0.0, Culture=neutral, PublicKeyToken=null'.] System.Runtime.Serialization.Formatters.Binary.BinaryAssemblyInfo.GetAssembly() +1871092 System.Runtime.Serialization.Formatters.Binary.ObjectReader.GetType(BinaryAssemblyInfo assemblyInfo, String name) +7545734 System.Runtime.Serialization.Formatters.Binary.ObjectMap..ctor(String objectName, String[] memberNames, BinaryTypeEnum[] binaryTypeEnumA, Object[] typeInformationA, Int32[] memberAssemIds, ObjectReader objectReader, Int32 objectId, BinaryAssemblyInfo assemblyInfo, SizedArray assemIdToAssemblyTable) +120 System.Runtime.Serialization.Formatters.Binary.ObjectMap.Create(String name, String[] memberNames, BinaryTypeEnum[] binaryTypeEnumA, Object[] typeInformationA, Int32[] memberAssemIds, ObjectReader objectReader, Int32 objectId, BinaryAssemblyInfo assemblyInfo, SizedArray assemIdToAssemblyTable) +52 System.Runtime.Serialization.Formatters.Binary.__BinaryParser.ReadObjectWithMapTyped(BinaryObjectWithMapTyped record) +190 System.Runtime.Serialization.Formatters.Binary.__BinaryParser.ReadObjectWithMapTyped(BinaryHeaderEnum binaryHeaderEnum) +61 System.Runtime.Serialization.Formatters.Binary.__BinaryParser.Run() +253 System.Runtime.Serialization.Formatters.Binary.ObjectReader.Deserialize(HeaderHandler handler, __BinaryParser serParser, Boolean fCheck, Boolean isCrossAppDomain, IMethodCallMessage methodCallMessage) +168 System.Runtime.Serialization.Formatters.Binary.BinaryFormatter.Deserialize(Stream serializationStream, HeaderHandler handler, Boolean fCheck, Boolean isCrossAppDomain, IMethodCallMessage methodCallMessage) +203 System.Web.Util.AltSerialization.ReadValueFromStream(BinaryReader reader) +788 System.Web.SessionState.SessionStateItemCollection.ReadValueFromStreamWithAssert() +55 System.Web.SessionState.SessionStateItemCollection.DeserializeItem(String name, Boolean check) +281 System.Web.SessionState.SessionStateItemCollection.get_Item(String name) +19 System.Web.SessionState.HttpSessionStateContainer.get_Item(String name) +13 System.Web.SessionState.HttpSessionState.get_Item(String name) +13 ASPTesting._Default.Page_Load(Object sender, EventArgs e) in C:\Documents and Settings\sarsstu\My Documents\Projects\Testing\ASPTesting\ASPTesting\Default.aspx.cs:20 System.Web.Util.CalliHelper.EventArgFunctionCaller(IntPtr fp, Object o, Object t, EventArgs e) +14 System.Web.Util.CalliEventHandlerDelegateProxy.Callback(Object sender, EventArgs e) +35 System.Web.UI.Control.OnLoad(EventArgs e) +99 System.Web.UI.Control.LoadRecursive() +50 System.Web.UI.Page.ProcessRequestMain(Boolean includeStagesBeforeAsyncPoint, Boolean includeStagesAfterAsyncPoint) +627 Thanks to everyone in advance.

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  • Can this be done with multiple inhertance?

    - by Milo
    Here is what I would like to do. Say I have Class Widget. I then create Button from Widget. I then create ModifiedWidget which re-implements certain functions of Widget. I then want Button to use ModifiedWidget rather than plain Widget. Is this possible to do some how? Thanks class Button : public Widget; class SuperButton : public Button, public ModifiedWidget; I'm just not sure if that would do what I want it to though.

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  • Persisting non-entity class that extends an entity (jpa) - example?

    - by Michal Minicki
    The JPA tutorial states that one can have a non-entity that extends entity class: Entities may extend both entity and non-entity classes, and non-entity classes may extend entity classes. - http://java.sun.com/javaee/5/docs/tutorial/doc/bnbqa.html Is it possible to persist such structure? I want to do this: @Entity abstract class Test { ... } class FirstConcreteTest extends Test { ... } // Non-ntity class SecondConcreteTest extends Test { ... } // Non-entity Test test = new FirstConcreteTest(); em.persist(test); What I would like it to do is to persist all fields mapped on abstract Test to a common database table for all concrete classes (first and second), leaving all fields of first and second test class unpersisted (these can contain stuff like EJBs, jdbc pools, etc). And a bonus question. Is it possible to persist abstract property too? @Entity abstract class Test { @Column @Access(AccessType.PROPERTY) abstract public String getName(); } class SecondConcreteTest extends Test { public String getName() { return "Second Concrete Test"; } }

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  • select from multiple tables with different columns

    - by Qaiser Iftikhar
    Say I got this sql schema. Table Job: id,title, type, is_enabled Table JobFileCopy: job_id,from_path,to_path Table JobFileDelete: job_id, file_path Table JobStartProcess: job_id, file_path, arguments, working_directory There are many other tables with varying number of columns and they all got foreign key job_id which is linked to id in table Job. My questions: Is this the right approach? I don't have requirement to delete anything at anytime. I will require to select and insert mostly. Secondly, what is the best approach to get the list of jobs with relevant details from all the different tables in a single database hit? e.g I would like to select top 20 jobs with details, their details can be in any table (depends on column type in table Job) which I don't know until runtime. Thanks in advance. Regards,

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  • How to implement a C# interface in F#?

    - by Anton Andreev
    I would like to implement the following C# interface in F#: using System; using System.Collections.Generic; using System.Linq; using System.Text; using Mono.Addins; [TypeExtensionPoint] public interface ISparqlCommand { string Name { get; } object Run(Dictionary<string, string> NamespacesDictionary, org.openrdf.repository.Repository repository, params object[] argsRest); } This is what I have tried, but it gives me: "Incomplete structured construct at or before this point in expression" #light module Module1 open System open System.Collections.Generic; type MyClass() = interface ISparqlCommand with member this.Name = "Finding the path between two tops in the Graph" member this.Run(NamespacesDictionary, repository, argsRest) = new System.Object What am I doing wrong? Maybe indentation is wrong?

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