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  • Run word on server for COM to work??

    - by chupinette
    I got this from php.net website. This is related to the problem I am having with tho code below. Can anyone explain me what the following does. I am using Vista. What does running Word on server implies? In order to get the Word example running, do the following on the server side. Worked for me... 1. Click START--RUN and enter "dcomcnfg" 2. In the "Applications" tab, go down to "Microsoft Word Document" 3. Click PROPERTIES button 4. Go to the "Security" Tab 5. Click "Use custom access permissions", and then click EDIT 6. Click ADD and then click SHOW USERS 7. Highlight the IIS anonymous user account (usually IUSR_), click ADD 8. Go back to the "Security" tab by hitting OK 9. Click "Use custom launch permissions", and the click EDIT 10. Click ADD and then click SHOW USERS 11. Highlight the IIS anonymous user account (usually IUSR_), click ADD 12. Hit OK, and then hit APPLY. Also, you should look at the "Identity" tab in the Microsoft Word Document PROPERTIES and see that it is set to "Interactive User" ALSO, log into the machine AS the IUSR_ account, start word, and make sure to click through the dialog boxes that Word shows the first time it is run for a certain user. In other words, make sure Word opens cleanly for the IUSR_ user. <?php // starting word $word = new COM("word.application") or die("Unable to instantiate Word"); echo "Loaded Word, version {$word->Version}\n"; //bring it to front $word->Visible = 1; //open an empty document $word->Documents->Add(); //do some weird stuff $word->Selection->TypeText("This is a test..."); $word->Documents[1]->SaveAs("Useless test.doc"); //closing word $word->Quit(); //free the object $word = null; ?>

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  • Asp.net MVC VirtualPathProvider views parse error

    - by madcapnmckay
    Hi, I am working on a plugin system for Asp.net MVC 2. I have a dll containing controllers and views as embedded resources. I scan the plugin dlls for controller using StructureMap and I then can pull them out and instantiate them when requested. This works fine. I then have a VirtualPathProvider which I adapted from this post public class AssemblyResourceProvider : VirtualPathProvider { protected virtual string WidgetDirectory { get { return "~/bin"; } } private bool IsAppResourcePath(string virtualPath) { var checkPath = VirtualPathUtility.ToAppRelative(virtualPath); return checkPath.StartsWith(WidgetDirectory, StringComparison.InvariantCultureIgnoreCase); } public override bool FileExists(string virtualPath) { return (IsAppResourcePath(virtualPath) || base.FileExists(virtualPath)); } public override VirtualFile GetFile(string virtualPath) { return IsAppResourcePath(virtualPath) ? new AssemblyResourceVirtualFile(virtualPath) : base.GetFile(virtualPath); } public override CacheDependency GetCacheDependency(string virtualPath, IEnumerable virtualPathDependencies, DateTime utcStart) { return IsAppResourcePath(virtualPath) ? null : base.GetCacheDependency(virtualPath, virtualPathDependencies, utcStart); } } internal class AssemblyResourceVirtualFile : VirtualFile { private readonly string path; public AssemblyResourceVirtualFile(string virtualPath) : base(virtualPath) { path = VirtualPathUtility.ToAppRelative(virtualPath); } public override Stream Open() { var parts = path.Split('/'); var resourceName = Path.GetFileName(path); var apath = HttpContext.Current.Server.MapPath(Path.GetDirectoryName(path)); var assembly = Assembly.LoadFile(apath); return assembly != null ? assembly.GetManifestResourceStream(assembly.GetManifestResourceNames().SingleOrDefault(s => string.Compare(s, resourceName, true) == 0)) : null; } } The VPP seems to be working fine also. The view is found and is pulled out into a stream. I then receive a parse error Could not load type 'System.Web.Mvc.ViewUserControl<dynamic>'. which I can't find mentioned in any previous example of pluggable views. Why would my view not compile at this stage? Thanks for any help, Ian EDIT: Getting closer to an answer but not quite clear why things aren't compiling. Based on the comments I checked the versions and everything is in V2, I believe dynamic was brought in at V2 so this is fine. I don't even have V3 installed so it can't be that. I have however got the view to render, if I remove the <dynamic> altogether. So a VPP works but only if the view is not strongly typed or dynamic This makes sense for the strongly typed scenario as the type is in the dynamically loaded dll so the viewengine will not be aware of it, even though the dll is in the bin. Is there a way to load types at app start? Considering having a go with MEF instead of my bespoke Structuremap solution. What do you think?

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  • Silverlight 3 - Creating Custom Objects inside a Merged ResourceDictionary

    - by Tony Heupel
    I have custom classes that I currently instantiate within App.xaml as resources. I want to move these custom objects into a Merged ResourceDictionary, where they are used within styles, and keep them close to where they are used. Here's an example of what I want, arbitrarily using fake converter objects, but they could be any custom object... App.xaml (namespace declarations ommitted): <Application.Resources> <ResourceDictionary> <ResourceDictionary.MergedDictionaries> <ResourceDictionary Source="Merged.xaml" /> </ResourceDictionary.MergedDictionaries> <Style x:Key="SomeStyle" TargetType="SomeControl"> ... </Style> ... </ResourceDictionary> And then in Merged.xaml (namespace declarations omitted): <ResourceDictionary> <cvt:VisibilityToBoolConverter x:Key="BoolToVisibility" Inverted="True"/> <cvt:VisibilityToBoolConverter x:Key="NotBoolToVisibility" Inverted="True" Not="True"/> <Style x:Key="SomethingThatUsesVisibilityToBoolConvertersStyle" TargetType="SomeOtherControl"> .... </Style> </ResourceDictionary> The issue I'm seeing is this: when I create the BoolToVisibility and NotBoolToVisibility objects (as well instantiating other objects that are instances of custom classes I have created) just as part Application.Resources, they are created and all the references work as expected; however, when I move these into a Merged Resource Dictionary (as I have in the sample above), I get a malformed Application exception when the Silverlight application loads. I belive this to be an issue with how objects are instantiated differently in Merged Resource Dictionaries (I belive it is more of a lazy-load approach), but I would expect it to work nonetheless. I am very much able to add Style objects, DataTemplates, ControlTemplates, and the like. But when I want to create instances of custom classes that are named or keyed using Xaml, it works great inside of App.xaml's Application.Resources directly and Application.Resources/ResourceDictionary as well. As soon as they are moved into a merged dictionary, it throws the exception. Is this by design? Any other ideas that work? Thanks in advance...

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  • To use AES with 256 bits in inbuild java 1.4 api.

    - by sahil garg
    I am able to encrypt with AES 128 but with more key length it fails. code using AES 128 is as below. import java.security.*; import javax.crypto.*; import javax.crypto.spec.*; import java.io.*; /** * This program generates a AES key, retrieves its raw bytes, and * then reinstantiates a AES key from the key bytes. * The reinstantiated key is used to initialize a AES cipher for * encryption and decryption. */ public class AES { /** * Turns array of bytes into string * * @param buf Array of bytes to convert to hex string * @return Generated hex string */ public static String asHex (byte buf[]) { StringBuffer strbuf = new StringBuffer(buf.length * 2); int i; for (i = 0; i < buf.length; i++) { if (((int) buf[i] & 0xff) < 0x10) strbuf.append("0"); strbuf.append(Long.toString((int) buf[i] & 0xff, 16)); } return strbuf.toString(); } public static void main(String[] args) throws Exception { String message="This is just an example"; // Get the KeyGenerator KeyGenerator kgen = KeyGenerator.getInstance("AES"); kgen.init(128); // 192 and 256 bits may not be available // Generate the secret key specs. SecretKey skey = kgen.generateKey(); byte[] raw = skey.getEncoded(); SecretKeySpec skeySpec = new SecretKeySpec(raw, "AES"); // Instantiate the cipher Cipher cipher = Cipher.getInstance("AES"); cipher.init(Cipher.ENCRYPT_MODE, skeySpec); byte[] encrypted =cipher.doFinal("welcome".getBytes()); System.out.println("encrypted string: " + asHex(encrypted)); cipher.init(Cipher.DECRYPT_MODE, skeySpec); byte[] original = cipher.doFinal(encrypted); String originalString = new String(original); System.out.println("Original string: " + originalString + " " + asHex(original)); } }

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  • Can a View Controller manage more than 1 nib based view?

    - by Hugo Brynjar
    I have a VC controlling a screen of content that has 2 modes; a normal mode and an edit mode. Can I create a single VC with 2 views, each from separate nibs? In many situations on the iphone, you have a VC which controls an associated view. Then on a button press or other event, a new VC is loaded and its view becomes the top level view etc. But in this situation, I have 2 modes that I want to use the same VC for, because they are closely related. So I want a VC which can swap in/out 2 views. As per here: http://stackoverflow.com/questions/863321/iphone-how-to-load-a-view-using-a-nib-file-created-with-interface-builder/2683153#2683153 I have found that I can load a VC with an associated view from a nib and then later on load a different view from another nib and make that new view the active view. NSArray *nibObjects = [[NSBundle mainBundle] loadNibNamed:@"EditMode" owner:self options:nil]; UIView *theEditView = [nibObjects objectAtIndex:0]; self.editView = theEditView; [self.view addSubview:theEditView]; The secondary nib has outlets wired up to the VC like the primary nib. When the new nib is loaded, the outlets are all connected up fine and everything works nicely. Unfortunately when this edit view is then removed, there doesn't seem to be any elegant way of getting the outlets hooked up again to the (normal mode) view from the original nib. Nib loading and outlet setting seems a once only thing. So, if you want to have a VC that swaps in/out 2 views without creating a new VC, what are the options? 1) You can do everything in code, but I want to use nibs because it makes creating the UI simpler. 2) You have 1 nib for your VC and just hide/show elements using the hidden property of UIView and its subclasses. 3) You load a new nib as described above. This is fine for the new nib, but how do you sort the outlets when you go back to the original nib. 4) Give up and accept having a 1:1 between VCs and nibs. There is a nib for normal mode, a nib for edit mode and each mode has a VC that subclasses a common superclass. In the end, I went with 4) and it works, but requires a fair amount of extra work, because I have a model class that I instantiate in normal mode and then have to pass to the edit mode VC because both modes need access to the model. I'm also using NSTimer and have to start and stop the timer in each mode. It is because of all this shared functionality that I wanted a single VC with 2 nibs in the first place.

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  • What is the best workaround for the WCF client `using` block issue?

    - by Eric King
    I like instantiating my WCF service clients within a using block as it's pretty much the standard way to use resources that implement IDisposable: using (var client = new SomeWCFServiceClient()) { //Do something with the client } But, as noted in this MSDN article, wrapping a WCF client in a using block could mask any errors that result in the client being left in a faulted state (like a timeout or communication problem). Long story short, when Dispose() is called, the client's Close() method fires, but throws and error because it's in a faulted state. The original exception is then masked by the second exception. Not good. The suggested workaround in the MSDN article is to completely avoid using a using block, and to instead instantiate your clients and use them something like this: try { ... client.Close(); } catch (CommunicationException e) { ... client.Abort(); } catch (TimeoutException e) { ... client.Abort(); } catch (Exception e) { ... client.Abort(); throw; } Compared to the using block, I think that's ugly. And a lot of code to write each time you need a client. Luckily, I found a few other workarounds, such as this one on IServiceOriented. You start with: public delegate void UseServiceDelegate<T>(T proxy); public static class Service<T> { public static ChannelFactory<T> _channelFactory = new ChannelFactory<T>(""); public static void Use(UseServiceDelegate<T> codeBlock) { IClientChannel proxy = (IClientChannel)_channelFactory.CreateChannel(); bool success = false; try { codeBlock((T)proxy); proxy.Close(); success = true; } finally { if (!success) { proxy.Abort(); } } } } Which then allows: Service<IOrderService>.Use(orderService => { orderService.PlaceOrder(request); } That's not bad, but I don't think it's as expressive and easily understandable as the using block. The workaround I'm currently trying to use I first read about on blog.davidbarret.net. Basically you override the client's Dispose() method wherever you use it. Something like: public partial class SomeWCFServiceClient : IDisposable { void IDisposable.Dispose() { if (this.State == CommunicationState.Faulted) { this.Abort(); } else { this.Close(); } } } This appears to be able to allow the using block again without the danger of masking a faulted state exception. So, are there any other gotchas I have to look out for using these workarounds? Has anybody come up with anything better?

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  • Brainstorming: Weird JPA problem, possibly classpath or jar versioning problem???

    - by Vinnie
    I'm seeing a weird error message and am looking for some ideas as to what the problem could be. I'm sort of new to using the JPA. I have an application where I'm using Spring's Entity Manager Factory (LocalContainerEntityManagerFactoryBean), EclipseLink as my ORM provider, connected to a MySQL DB and built with Maven. I'm not sure if any of this matters..... When I deploy this application to Glassfish, the application works as expected. The problem is, I've created a set of stand alone unit tests to run outside of Glassfish that aren't working correctly. I get the following error (I've edited the class names a little) com.xyz.abc.services.persistence.entity.MyEntity cannot be cast to com.xyz.abc.services.persistence.entity.MyEntity The object cannot be cast to a class of the same type? How can that be? Here's a snippet of the code that is in error Query q = entityManager.createNamedQuery("MyEntity.findAll"); List entityObjects = q.getResultList(); for (Object entityObject: entityObjects) { com.xyz.abc.services.persistence.entity.MyEntity entity = (com.xyz.abc.services.persistence.entity.MyEntity) entityObject; Previously, I had this code that produced the same error: CriteriaQuery cq = entityManager.getCriteriaBuilder().createQuery(); cq.select(cq.from(com.xyz.abc.services.persistence.entity.MyEntity.class)); List entityObjects = entityManager.createQuery(cq).getResultList(); for (Object entityObject: entityObjects) { com.xyz.abc.services.persistence.entity.MyEntity entity = (com.xyz.abc.services.persistence.entity.MyEntity) entityObject; This code is question is the same that I have deployed to the server. Here's the innermost exception if it helps Caused by: java.lang.ClassCastException: com.xyz.abc.services.persistence.entity.MyEntity cannot be cast to com.xyz.abc.services.persistence.entity.MyEntity at com.xyz.abc.services.persistence.entity.factory.MyEntityFactory.createBeans(MyEntityFactory.java:47) at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39) at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25) at java.lang.reflect.Method.invoke(Method.java:597) at org.springframework.beans.factory.support.SimpleInstantiationStrategy.instantiate(SimpleInstantiationStrategy.java:115) ... 37 more I'm guessing that there's some jar I'm using in Glassfish that is different than the ones I'm using in test. I've looked at all the jars I have listed as "provided" and am pretty sure they are all the same ones from Glassfish. Let me know if you've seen this weird issue before, or any ideas for correcting it.

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  • VS 2008 irritating copy constructor link dependency

    - by Paul Hollingsworth
    Hi guys, I've run into the following annoying and seemingly incorrect behaviour in the Visual Studio 2008 C++ compiler: Suppose I have a class library - Car.lib - that uses a "Car" class, with a header called "Car.h": class Car { public: void Drive() { Accelerate(); } void Accelerate(); }; What I'm actually trying to do is use the Car headers (for some other functions), but without having to link with Car.lib itself (the actual class is not called "Car" but I am sanitising this example). If I #include "Car.h" in the .cpp file used to build a managed C++ .dll, but never refer to Car, everything compiles and links fine. This is because I never instantiate a Car object. However, the following: namespace { class Car { public: Car(const Car& rhs) { Accelerate(); } void Accelerate(); }; } leaves me with the link error: Error 2 error LNK2001: unresolved external symbol "public: void __thiscall `anonymous namespace'::Car::Accelerate(void)" (?Accelerate@Car@?A0xce3bb5ed@@$$FQAEXXZ) CREObjectWrapper.obj CREObjectBuilderWrapper Note I've declared the whole thing inside an anonymous namespace so there's no way that the Car functions could be exported from the .DLL in any case. Declaring the copy constructor out-of-line makes no difference. i.e. the following also fails to link: class Car { public: Car(const Car& rhs); void Accelerate(); }; Car::Car(const Car& rhs) { Accelerate(); } It's something specifically to do with the copy constructor note, because the following, for example, does link: class Car { public: Car() { Accelerate(); } void Accelerate(); }; I am not a C++ standards guru but this doesn't seem correct to me. Surely the compiler still should not have had to even generate any code that calls the Car copy constructor. Can anyone confirm if this behaviour is correct? It's been a while since I used C++ - but I don't think this used to be an issue with Visual Studio 6.0 for example. Can anyone suggest a workaround that allows one to "re-use" the Accelerate method from within the copy constructor and still have the copy constructor declared inline?

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  • How to write a cctor and op= for a factory class with ptr to abstract member field?

    - by Kache4
    I'm extracting files from zip and rar archives into raw buffers. I created the following to wrap minizip and unrarlib: Archive.hpp #include "ArchiveBase.hpp" #include "ArchiveDerived.hpp" class Archive { public: Archive(string path) { /* logic here to determine type */ switch(type) { case RAR: archive_ = new ArchiveRar(path); break; case ZIP: archive_ = new ArchiveZip(path); break; case UNKNOWN_ARCHIVE: throw; break; } } Archive(Archive& other) { archive_ = // how do I copy an abstract class? } ~Archive() { delete archive_; } void passThrough(ArchiveBase::Data& data) { archive_->passThrough(data); } Archive& operator = (Archive& other) { if (this == &other) return *this; ArchiveBase* newArchive = // can't instantiate.... delete archive_; archive_ = newArchive; return *this; } private: ArchiveBase* archive_; } ArchiveBase.hpp class ArchiveBase { public: // Is there any way to put this struct in Archive instead, // so that outside classes instantiating one could use // Archive::Data instead of ArchiveBase::Data? struct Data { int field; }; virtual void passThrough(Data& data) = 0; /* more methods */ } ArchiveDerived.hpp "Derived" being "Zip" or "Rar" #include "ArchiveBase.hpp" class ArchiveDerived : public ArchiveBase { public: ArchiveDerived(string path); void passThrough(ArchiveBase::Data& data); private: /* fields needed by minizip/unrarlib */ // example zip: unzFile zipFile_; // example rar: RARHANDLE rarFile_; } ArchiveDerived.cpp #include "ArchiveDerived.hpp" ArchiveDerived::ArchiveDerived(string path) { //implement } ArchiveDerived::passThrough(ArchiveBase::Data& data) { //implement } Somebody had suggested I use this design so that I could do: Archive archiveFile(pathToZipOrRar); archiveFile.passThrough(extractParams); // yay polymorphism! How do I write a cctor for Archive? What about op= for Archive? What can I do about "renaming" ArchiveBase::Data to Archive::Data? (Both minizip and unrarlib use such structs for input and output. Data is generic for Zip & Rar and later is used to create the respective library's struct.)

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  • Is it possible to use XStream with an abstract node?

    - by Dan Watling
    My client application is making calls to a service that returns a common "root" XML, but a different result node. The "root" XML contains possible error codes. Is it possible to use XStream in this scenario? Example: public class RootNode { ErrorInfo errorInfo; BaseResult result; ... } public class ErrorInfo { String message; ... } public abstract BaseResult { } public class SearchResult extends BaseResult { List<Object> searchResults; ... } public class AccountResult extends BaseResult { String name; ... } The XML coming back could be one of two formats: <root> <errorInfo><message>...</message></errorInfo> <result> <searchResults>...</searchResults> </result> </root> OR <root> <errorInfo><message>...</message></errorInfo> <result> <name>...</name> </result> </root> I have set up my XStream object as follows: XStream x = new XStream(); x.alias("root", Root.class); x.alias("errorInfo", ErrorInfo.class); x.alias("result", <SearchResult.class OR AccountResult.class depending on what I am expecting back>); Of course, when I run this I receive an error telling me XStream cannot instantiate the base class (BaseResult). For fun, I also converted the BaseResult into an interface but received a similar error. I've looked through XStream's documentation and it isn't clear to me how to handle a situation like the one I just described. Is it even possible to do using XStream? Thanks, -Dan

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  • Multiple Graphics2D Objects

    - by Trizicus
    I have a Graphics object of JPanel and that is working fine: import java.awt.Color; import java.awt.Graphics; import java.awt.Graphics2D; import java.awt.geom.Rectangle2D; import javax.swing.JPanel; public class GraphicsTest extends JPanel { private Graphics2D g2d; private String state; private int x, y; @Override public void paintComponent(Graphics g) { super.paintComponent(g); g2d = (Graphics2D) g; g2d.setClip(0, 0, getWidth(), getHeight()); g2d.setColor(Color.BLACK); g2d.drawString("STATE: " + state, 5, 15); g2d.drawString("Mouse Position: " + x + ", " + y, 5, 30); g2d.setColor(Color.red); Rectangle2D r2d = new Rectangle2D.Double(x,y,10,10); g2d.draw(r2d); Test t = new Test(); super.add(t); repaint(); } public void setState(String state) { this.state = state; } public String getState() { return state; } public void setX(int x) { this.x = x; } public void setY(int y) { this.y = y; } } I was experimenting with a new Graphics component and when I instantiate a new Test and add it in GraphicsTest nothing happens. What is it that I am doing wrong? import java.awt.Color; import java.awt.Graphics; import java.awt.Graphics2D; import java.awt.geom.Rectangle2D; import javax.swing.JComponent; public class Test extends JComponent { private Graphics2D g2d; private String state; private int x, y; @Override public void paintComponent(Graphics g) { super.paintComponent(g); g2d = (Graphics2D) g.create(); g2d.setColor(Color.GREEN); g2d.fill(new Rectangle2D.Double(60, 60, 10, 10)); repaint(); } public void setState(String state) { this.state = state; } public String getState() { return state; } public void setX(int x) { this.x = x; } public void setY(int y) { this.y = y; } } Thanks!

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  • How to pass ctor args in Activator.CreateInstance?

    - by thames
    I need a performance enhanced Activator.CreateInstance() and came across this article by Miron Abramson that uses a factory to create the instance in IL and then cache it. (I've included code below from Miron Abramson's site in case it somehow disappears). I'm new to IL Emit code and anything beyond Activator.CreateInstance() for instantiating a class and any help would be much appreciative. My problem is that I need to create an instance of an object that takes a ctor with a parameter. I see there is a way to pass in the Type of the parameter, but is there a way to pass in the value of the ctor parameter as well? If possible, I would like to use a method similar to CreateObjectFactory<T>(params object[] constructorParams) as some objects I want to instantiate may have more than 1 ctor param. // Source: http://mironabramson.com/blog/post/2008/08/Fast-version-of-the-ActivatorCreateInstance-method-using-IL.aspx public static class FastObjectFactory { private static readonly Hashtable creatorCache = Hashtable.Synchronized(new Hashtable()); private readonly static Type coType = typeof(CreateObject); public delegate object CreateObject(); /// /// Create an object that will used as a 'factory' to the specified type T /// public static CreateObject CreateObjectFactory() where T : class { Type t = typeof(T); FastObjectFactory.CreateObject c = creatorCache[t] as FastObjectFactory.CreateObject; if (c == null) { lock (creatorCache.SyncRoot) { c = creatorCache[t] as FastObjectFactory.CreateObject; if (c != null) { return c; } DynamicMethod dynMethod = new DynamicMethod("DM$OBJ_FACTORY_" + t.Name, typeof(object), null, t); ILGenerator ilGen = dynMethod.GetILGenerator(); ilGen.Emit(OpCodes.Newobj, t.GetConstructor(Type.EmptyTypes)); ilGen.Emit(OpCodes.Ret); c = (CreateObject)dynMethod.CreateDelegate(coType); creatorCache.Add(t, c); } } return c; } } Update to Miron's code from commentor on his post 2010-01-11 public static class FastObjectFactory2<T> where T : class, new() { public static Func<T> CreateObject { get; private set; } static FastObjectFactory2() { Type objType = typeof(T); var dynMethod = new DynamicMethod("DM$OBJ_FACTORY_" + objType.Name, objType, null, objType); ILGenerator ilGen = dynMethod.GetILGenerator(); ilGen.Emit(OpCodes.Newobj, objType.GetConstructor(Type.EmptyTypes)); ilGen.Emit(OpCodes.Ret); CreateObject = (Func<T>) dynMethod.CreateDelegate(typeof(Func<T>)); } }

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  • Avoiding circular project/assembly references in Visual Studio with statically typed dependency conf

    - by svnpttrssn
    First, I want to say that I am not interested in debating about any non-helpful "answers" to my question, with suggestions to putting everything in one assembly, i.e. there is no need for anyone to provide webpages such as the page titled with "Separate Assemblies != Loose Coupling". Now, my question is if it somehow (maybe with some Visual Studio configuration to allow for circular project dependencies?) is possible to use one project/assembly (I am here calling it the "ServiceLocator" assembly) for retrieving concrete implementation classes, (e.g. with StructureMap) which can be referred to from other projects, while it of course is also necessary for the the ServiceLocator itself to refer to other projects with the interfaces and the implementations ? Visual Studio project example, illustrating the kind of dependency structure I am talking about: http://img10.imageshack.us/img10/8838/testingdependencyinject.png Please note in the above picture, the problem is how to let the classes in "ApplicationLayerServiceImplementations" retrieve and instantiate classes that implement the interfaces in "DomainLayerServiceInterfaces". The goal is here to not refer directly to the classes in "DomainLayerServiceImplementations", but rather to try using the project "ServiceLocator" to retrieve such classes, but then the circular dependency problem occurrs... For example, a "UserInterfaceLayer" project/assembly might contain this kind of code: ContainerBootstrapper.BootstrapStructureMap(); // located in "ServiceLocator" project/assembly MyDomainLayerInterface myDomainLayerInterface = ObjectFactory.GetInstance<MyDomainLayerInterface>(); // refering to project/assembly "DomainLayerServiceInterfaces" myDomainLayerInterface.MyDomainLayerMethod(); MyApplicationLayerInterface myApplicationLayerInterface = ObjectFactory.GetInstance<MyApplicationLayerInterface>(); // refering to project/assembly "ApplicationLayerServiceInterfaces" myApplicationLayerInterface.MyApplicationLayerMethod(); The above code do not refer to the implementation projects/assemblies ApplicationLayerServiceImplementations and DomainLayerServiceImplementations, which contain this kind of code: public class MyApplicationLayerImplementation : MyApplicationLayerInterface and public class MyDomainLayerImplementation : MyDomainLayerInterface The "ServiceLocator" project/assembly might contain this code: using ApplicationLayerServiceImplementations; using ApplicationLayerServiceInterfaces; using DomainLayerServiceImplementations; using DomainLayerServiceInterfaces; using StructureMap; namespace ServiceLocator { public static class ContainerBootstrapper { public static void BootstrapStructureMap() { ObjectFactory.Initialize(x => { // The two interfaces and the two implementations below are located in four different Visual Studio projects x.ForRequestedType<MyDomainLayerInterface>().TheDefaultIsConcreteType<MyDomainLayerImplementation>(); x.ForRequestedType<MyApplicationLayerInterface>().TheDefaultIsConcreteType<MyApplicationLayerImplementation>(); }); } } } So far, no problem, but the problem occurs when I want to let the class "MyApplicationLayerImplementation" in the project/assembly "ApplicationLayerServiceImplementations" use the "ServiceLocator" project/assembly for retrieving an implementation of "MyDomainLayerInterface". When I try to do that, i.e. add a reference from "MyApplicationLayerImplementation" to "ServiceLocator", then Visual Studio complains about circular dependencies between projects. Is there any nice solution to this problem, which does not imply using refactoring-unfriendly string based xml-configuration which breaks whenever an interface or class or its namespace is renamed ? / Sven

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  • Can't read excel file after creating it using File.WriteAllText() function

    - by Srikanth Mattihalli
    public void ExportDataSetToExcel(DataTable dt) { HttpResponse response = HttpContext.Current.Response; response.Clear(); response.Charset = "utf-8"; response.ContentEncoding = Encoding.GetEncoding("utf-8"); response.ContentType = "application/vnd.ms-excel"; Random Rand = new Random(); int iNum = Rand.Next(10000, 99999); string extension = ".xls"; string filenamepath = AppDomain.CurrentDomain.BaseDirectory + "graphs\\" + iNum + ".xls"; string file_path = "graphs/" + iNum + extension; response.AddHeader("Content-Disposition", "attachment;filename=\"" + iNum + "\""); string query = "insert into graphtable(graphtitle,graphpath,creategraph,year) VALUES('" + iNum.ToString() + "','" + file_path + "','" + true + "','" + DateTime.Now.Year.ToString() + "')"; try { int n = connect.UpdateDb(query); if (n > 0) { resultLabel.Text = "Merge Successfull"; } else { resultLabel.Text = " Merge Failed"; } resultLabel.Visible = true; } catch { } using (StringWriter sw = new StringWriter()) { using (HtmlTextWriter htw = new HtmlTextWriter(sw)) { // instantiate a datagrid DataGrid dg = new DataGrid(); dg.DataSource = dt; //ds.Tables[0]; dg.DataBind(); dg.RenderControl(htw); File.WriteAllText(filenamepath, sw.ToString()); // File.WriteAllText(filenamepath, sw.ToString(), Encoding.UTF8); response.Write(sw.ToString()); response.End(); } } } Hi all, I have created an excel sheet from datatable using above function. I want to read the excel sheet programatically using the below connectionstring. This string works fine for all other excel sheets but not for the one i created using the above function. I guess it is because of excel version problem. OleDbConnection conn= new OleDbConnection("Data Source='" + path +"';provider=Microsoft.Jet.OLEDB.4.0;Extended Properties=Excel 8.0;";); Can anyone suggest a way by which i can create an excel sheet such that it is readable again using above query. I cannot use Microsoft InterOp library as it is not supported by my host.

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  • Android Facebook SDK : post message without showing facebook page

    - by someone_ smiley
    I am trying to integrate Facebook to my Android app for social post. I have downloaded latest Facebook sdk from here and apply all setup require to post to facebook. Now i can post to facebook. But problem is that, when i run sample program from facebook sdk, a browser like page is open and user have to enter message himself there. but i dont want this page to showed up. i want a fixed message to post directly without opening facebook dialog box. But if there is noway to avoid this, please tell me how can i fixed certain part of message so that user can't modified it. Thanks in Advance Edit: this is message i got after using this project 04-10 11:44:34.691: I/dalvikvm(719): Failed resolving Lnet/xeomax/TestRocket/TestRocket; interface 22 'Lnet/xeomax/FBRocket/LoginListener;' 04-10 11:44:34.691: W/dalvikvm(719): Link of class 'Lnet/xeomax/TestRocket/TestRocket;' failed 04-10 11:44:34.691: D/AndroidRuntime(719): Shutting down VM 04-10 11:44:34.701: W/dalvikvm(719): threadid=1: thread exiting with uncaught exception (group=0x40015560) 04-10 11:44:34.781: E/AndroidRuntime(719): FATAL EXCEPTION: main 04-10 11:44:34.781: E/AndroidRuntime(719): java.lang.RuntimeException: Unable to instantiate activity ComponentInfo{net.xeomax.TestRocket/net.xeomax.TestRocket.TestRocket}: java.lang.ClassNotFoundException: net.xeomax.TestRocket.TestRocket in loader dalvik.system.PathClassLoader[/data/app/net.xeomax.TestRocket-1.apk] 04-10 11:44:34.781: E/AndroidRuntime(719): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:1569) 04-10 11:44:34.781: E/AndroidRuntime(719): at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:1663) 04-10 11:44:34.781: E/AndroidRuntime(719): at android.app.ActivityThread.access$1500(ActivityThread.java:117) 04-10 11:44:34.781: E/AndroidRuntime(719): at android.app.ActivityThread$H.handleMessage(ActivityThread.java:931) 04-10 11:44:34.781: E/AndroidRuntime(719): at android.os.Handler.dispatchMessage(Handler.java:99) 04-10 11:44:34.781: E/AndroidRuntime(719): at android.os.Looper.loop(Looper.java:130) 04-10 11:44:34.781: E/AndroidRuntime(719): at android.app.ActivityThread.main(ActivityThread.java:3683) 04-10 11:44:34.781: E/AndroidRuntime(719): at java.lang.reflect.Method.invokeNative(Native Method) 04-10 11:44:34.781: E/AndroidRuntime(719): at java.lang.reflect.Method.invoke(Method.java:507) 04-10 11:44:34.781: E/AndroidRuntime(719): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:839) 04-10 11:44:34.781: E/AndroidRuntime(719): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:597) 04-10 11:44:34.781: E/AndroidRuntime(719): at dalvik.system.NativeStart.main(Native Method) 04-10 11:44:34.781: E/AndroidRuntime(719): Caused by: java.lang.ClassNotFoundException: net.xeomax.TestRocket.TestRocket in loader dalvik.system.PathClassLoader[/data/app/net.xeomax.TestRocket-1.apk] 04-10 11:44:34.781: E/AndroidRuntime(719): at dalvik.system.PathClassLoader.findClass(PathClassLoader.java:240) 04-10 11:44:34.781: E/AndroidRuntime(719): at java.lang.ClassLoader.loadClass(ClassLoader.java:551) 04-10 11:44:34.781: E/AndroidRuntime(719): at java.lang.ClassLoader.loadClass(ClassLoader.java:511) 04-10 11:44:34.781: E/AndroidRuntime(719): at android.app.Instrumentation.newActivity(Instrumentation.java:1021) 04-10 11:44:34.781: E/AndroidRuntime(719): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:1561) 04-10 11:44:34.781: E/AndroidRuntime(719): ... 11 more

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  • how can we use AsynCallback method of web service in asp.net

    - by sameer
    Hi All, I was going through the proxy class which is generated using wsdl.exe found the asyncmethod like BeginAsynXXX() and EndAsyncXXX(). i understood how to utilize them on Windows application but i was wondering how can we use them in Web Application built using asp.net here is the code for web service client build as windows application.can any tell me how we can do this with web application. using System; using System.Runtime.Remoting.Messaging; using MyFactorize; class TestCallback { public static void Main(){ long factorizableNum = 12345; PrimeFactorizer pf = new PrimeFactorizer(); //Instantiate an AsyncCallback delegate to use as a parameter //in the BeginFactorize method. AsyncCallback cb = new AsyncCallback(TestCallback.FactorizeCallback); // Begin the Async call to Factorize, passing in our // AsyncCalback delegate and a reference // to our instance of PrimeFactorizer. IAsyncResult ar = pf.BeginFactorize(factorizableNum, cb, pf); // Keep track of the time it takes to complete the async call // as the call proceeds. int start = DateTime.Now.Second; int currentSecond = start; while (ar.IsCompleted == false){ if (currentSecond < DateTime.Now.Second) { currentSecond = DateTime.Now.Second; Console.WriteLine("Seconds Elapsed..." + (currentSecond - start).ToString() ); } } // Once the call has completed, you need a method to ensure the // thread executing this Main function // doesn't complete prior to the call-back function completing. Console.Write("Press Enter to quit"); int quitchar = Console.Read(); } // Set up a call-back function that is invoked by the proxy class // when the asynchronous operation completes. public static void FactorizeCallback(IAsyncResult ar) { // You passed in our instance of PrimeFactorizer in the third // parameter to BeginFactorize, which is accessible in the // AsyncState property. PrimeFactorizer pf = (PrimeFactorizer) ar.AsyncState; long[] results; // Get the completed results. results = pf.EndFactorize(ar); //Output the results. Console.Write("12345 factors into: "); int j; for (j = 0; j<results.Length;j++){ if (j == results.Length - 1) Console.WriteLine(results[j]); else Console.Write(results[j] + ", "); } } }

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  • Inference engine to calculate matching set according to internal rules

    - by Zecrates
    I have a set of objects with attributes and a bunch of rules that, when applied to the set of objects, provides a subset of those objects. To make this easier to understand I'll provide a concrete example. My objects are persons and each has three attributes: country of origin, gender and age group (all attributes are discrete). I have a bunch of rules, like "all males from the US", which correspond with subsets of this larger set of objects. I'm looking for either an existing Java "inference engine" or something similar, which will be able to map from the rules to a subset of persons, or advice on how to go about creating my own. I have read up on rule engines, but that term seems to be exclusively used for expert systems that externalize the business rules, and usually doesn't include any advanced form of inferencing. Here are some examples of the more complex scenarios I have to deal with: I need the conjunction of rules. So when presented with both "include all males" and "exclude all US persons in the 10 - 20 age group," I'm only interested in the males outside of the US, and the males within the US that are outside the 10 - 20 age group. Rules may have different priorities (explicitly defined). So a rule saying "exclude all males" will override a rule saying "include all US males." Rules may be conflicting. So I could have both an "include all males" and an "exclude all males" in which case the priorities will have to settle the issue. Rules are symmetric. So "include all males" is equivalent to "exclude all females." Rules (or rather subsets) may have meta rules (explicitly defined) associated with them. These meta rules will have to be applied in any case that the original rule is applied, or if the subset is reached via inferencing. So if a meta rule of "exclude the US" is attached to the rule "include all males", and I provide the engine with the rule "exclude all females," it should be able to inference that the "exclude all females" subset is equivalent to the "include all males" subset and as such apply the "exclude the US" rule additionally. I can in all likelihood live without item 5, but I do need all the other properties mentioned. Both my rules and objects are stored in a database and may be updated at any stage, so I'd need to instantiate the 'inference engine' when needed and destroy it afterward.

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  • Hotfixing Code running inside Web Container with Groovy

    - by raoulsson
    I have a webapp running that has a bug. I know how to fix it in the sources. However I cannot redeploy the app as I would have to take it offline to do so. (At least not right now). I now want to fix the code "at runtime". Surgery on the living object, so to speak. The app is implemented in Java and is build on top of Seam. I have added a Groovy Console to the app previous to the last release. (A way to run arbitrary code at runtime) The normal way of adding behaviour to a class with Groovy would be similar to this: String.metaClass.foo= { x -> x * x } println "anything".foo(3) This code added the method foo to java.lang.String and prints 9. I can do the same thing with classes running inside my webapp container. New instances will thereafter show the same behaviour: com.my.package.SomeService.metaClass.foo= { x -> x * x } def someService = new com.my.package.SomeService() println someService.foo(3) Works as excpected. All good so far. My problem is now that the container, the web framework, Seam in this case, has already instantiated and cached the classes that I would like to manipulate (that is change their behaviour to reflect my bug fix). Ideally this code would work: com.my.package.SomeService.metaClass.foo= { x -> x * x } def x = org.jboss.seam.Component.getInstance(com.my.package.SomeService) println x.foo(3) However the instantiation of SomeService has already happened and there is no effect. Thus I need a way to make my changes "sticky". Has the groovy magic gone after my script has been run? Well, after logging out and in again, I can run this piece of code and get the expected result: def someService = new com.my.package.SomeService() println someService.foo(3) So the foo method is still around and it looks like my change has been permanent... So I guess the question that remains is how to force Seam to re-instantiate all its components and/or how to permanently make the change on all living instances...?

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  • Crash in OS X Core Data Utility Tutorial

    - by vinogradov
    I'm trying to follow Apple's Core Data utility Tutorial. It was all going nicely, until... The tutorial uses a custom sub-class of NSManagedObject, called 'Run'. Run.h looks like this: #import <Foundation/Foundation.h> #import <CoreData/CoreData.h> @interface Run : NSManagedObject { NSInteger processID; } @property (retain) NSDate *date; @property (retain) NSDate *primitiveDate; @property NSInteger processID; @end Now, in Run.m we have an accessor method for the processID variable: - (void)setProcessID:(int)newProcessID { [self willChangeValueForKey:@"processID"]; processID = newProcessID; [self didChangeValueForKey:@"processID"]; } In main.m, we use functions to set up a managed object model and context, instantiate an entity called run, and add it to the context. We then get the current NSprocessInfo, in preparation for setting the processID of the run object. NSManagedObjectContext *moc = managedObjectContext(); NSEntityDescription *runEntity = [[mom entitiesByName] objectForKey:@"Run"]; Run *run = [[Run alloc] initWithEntity:runEntity insertIntoManagedObjectContext:moc]; NSProcessInfo *processInfo = [NSProcessInfo processInfo]; Next, we try to call the accessor method defined in Run.m to set the value of processID: [run setProcessID:[processInfo processIdentifier]]; And that's where it's crashing. The object run seems to exist (I can see it in the debugger), so I don't think I'm messaging nil; on the other hand, it doesn't look like the setProcessID: message is actually being received. I'm obviously still learning this stuff (that's what tutorials are for, right?), and I'm probably doing something really stupid. However, any help or suggestions would be gratefully received! ===MORE INFORMATION=== Following up on Jeremy's suggestions: The processID attribute in the model is set up like this: NSAttributeDescription *idAttribute = [[NSAttributeDescription alloc]init]; [idAttribute setName:@"processID"]; [idAttribute setAttributeType:NSInteger32AttributeType]; [idAttribute setOptional:NO]; [idAttribute setDefaultValue:[NSNumber numberWithInteger:-1]]; which seems a little odd; we are defining it as a scalar type, and then giving it an NSNumber object as its default value. In the associated class, Run, processID is defined as an NSInteger. Still, this should be OK - it's all copied directly from the tutorial. It seems to me that the problem is probably in there somewhere. By the way, the getter method for processID is defined like this: - (int)processID { [self willAccessValueForKey:@"processID"]; NSInteger pid = processID; [self didAccessValueForKey:@"processID"]; return pid; } and this method works fine; it accesses and unpacks the default int value of processID (-1). Thanks for the help so far!

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  • CoGetClassObject gives many First-chance exceptions in ATL project. Should I worry?

    - by Andrew
    Hello, I have written a COM object that in turn uses a thrid party ActiveX control. In my FinalConstruct() for my COM object, I instantiate the ActiveX control with the follow code: HRESULT hRes; LPCLASSFACTORY2 pClassFactory; hRes = CoInitializeEx(NULL,COINIT_APARTMENTTHREADED); bool bTest = SUCCEEDED(hRes); if (!bTest) return E_FAIL; if (SUCCEEDED(CoGetClassObject(__uuidof(SerialPortSniffer), CLSCTX_INPROC_SERVER, NULL, IID_IClassFactory2, (LPVOID *)(&pClassFactory)))) { ... more set up code When I step over the line if (SUCCEEDED(CoGetClassObject(__uuidof(SerialPortSniffer), ..., I get 20+ lines in the Output window stating: First-chance exception at 0x0523f82e in SillyComDriver.exe: 0xC0000005: Access violation writing location 0x00000000. I also get the lines: First-chance exception at 0x051e3f3d in SillyComDriver.exe: 0xC0000096: Privileged instruction. First-chance exception at 0x100ab9e6 in SillyComDriver.exe: 0xC000001D: Illegal Instruction. Notice these are first-chance exceptions. The program runs as expected I can access the third party methods/properties. Still, I'm left wondering why they are occurring. Perhaps my way of instantiating the ActiveX control (for which I want use of it's methods/properties and not it's GUI stuff) is incorrect? Besides the code I'm showing, I also put the line import "spsax.dll" no_namespace in the stdafx.h That's all the code necessary for my simple demo project. I noticed this problem because I had (inadvertently) set the "break on exceptions" options in my "real" project and it was breaking on this line. Once I removed it, it also works. If you're read this far thank you, and perhaps I can ask one other minor question. In my demo project, if I right click on SerialPortSniffer and "go to definition", it takes me to the file C:....\AppData\Local\Temp\spsax.tlh. Can someone explain that? Finally, in my "real" project, right clicking on SerialPortSniffer and going to difinition leads to "The symbol 'SerialPortSniffer' is not defined". It doesn't seem to affect the program though. Is there some setting I've messed up? By the way, all my code is written w/ VS2008. Thanks, Dave

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  • Good working habits to observe in project development?

    - by Will Marcouiller
    As my development experience grows, I see fit to stick to best practices from here and there to build somehow my own working practices while observing the conventions, etc. I'm currently working on a project which my goals is to graduate the security access model from an environment's Active Directory to another environment's automatically. I don't know for any of you, but as far as I'm concerned, I meet some real difficulties sticking to only one way, then develop. I mean, I learn something new everyday while visiting SO, and recently wanted to get acquainted with generics. On the other hand, I better know the Façade pattern which proved to be very practical in transactional programming in process systems. This seems to be less practical for desktop application as there are plenty of variables to consider in a desktop application that you don't have to care in transactional programming, as you're playing only with information data. As for my current project, I have: Groups; Organizational Units; Users. Which are all considered an entry in the Active Directory. This points out to be a good candidate for generics, as also approached this way by Bart de Smett's Linq to AD on CodePlex. He has a DirectorySource<T>, and to manage let's say groups, then he instantiate a source with the proper type: var groups = new DirectorySource<Group>(); This seems to be very a good way of doing. Despite, I seem to go from one pattern to another and I don't seem to be able to strictly stick to one. While I'm aware that one must not stay with only one way of doing, since each pattern statisfies certain advantages, while also illustrating disadvantages under some usage conditions, I seem to want to develop with both patterns having a singleton Façade class with the underlying factories which represent the sub systems: GroupsFactory; UsersFactory; OrganizationalUnitsFactory. Each of the factories offers the possible operations for their respective entity (group, user, OU). To make a very long story short, I often have plenty of ideas while developping and this causes me some trouble, as I go from an idea to another feeling completely lost after a while. Yet I understand the advantages and disavantages, I have no trouble choosing from one pattern to another depending on the situation. Nevertheless, when it comes to programming itself, if I'm not part of a team, I feel sometimes like I can't do anything good. That is, because I can't stand not doing something "perfect" the first time. The role I play within the project is both: the project manager and the programmer. I am more comfortable in the project manager role, architectural role, analytical role than the developer's. Has any of you some good habbits to observe in project development? Thanks to you all! =)

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  • Constructor Injection and when to use a Service Locator

    - by Simon
    I'm struggling to understand parts of StructureMap's usage. In particular, in the documentation a statement is made regarding a common anti-pattern, the use of StructureMap as a Service Locator only instead of constructor injection (code samples straight from Structuremap documentation): public ShippingScreenPresenter() { _service = ObjectFactory.GetInstance<IShippingService>(); _repository = ObjectFactory.GetInstance<IRepository>(); } instead of: public ShippingScreenPresenter(IShippingService service, IRepository repository) { _service = service; _repository = repository; } This is fine for a very short object graph, but when dealing with objects many levels deep, does this imply that you should pass down all the dependencies required by the deeper objects right from the top? Surely this breaks encapsulation and exposes too much information about the implementation of deeper objects. Let's say I'm using the Active Record pattern, so my record needs access to a data repository to be able to save and load itself. If this record is loaded inside an object, does that object call ObjectFactory.CreateInstance() and pass it into the active record's constructor? What if that object is inside another object. Does it take the IRepository in as its own parameter from further up? That would expose to the parent object the fact that we're access the data repository at this point, something the outer object probably shouldn't know. public class OuterClass { public OuterClass(IRepository repository) { // Why should I know that ThingThatNeedsRecord needs a repository? // that smells like exposed implementation to me, especially since // ThingThatNeedsRecord doesn't use the repo itself, but passes it // to the record. // Also where do I create repository? Have to instantiate it somewhere // up the chain of objects ThingThatNeedsRecord thing = new ThingThatNeedsRecord(repository); thing.GetAnswer("question"); } } public class ThingThatNeedsRecord { public ThingThatNeedsRecord(IRepository repository) { this.repository = repository; } public string GetAnswer(string someParam) { // create activeRecord(s) and process, returning some result // part of which contains: ActiveRecord record = new ActiveRecord(repository, key); } private IRepository repository; } public class ActiveRecord { public ActiveRecord(IRepository repository) { this.repository = repository; } public ActiveRecord(IRepository repository, int primaryKey); { this.repositry = repository; Load(primaryKey); } public void Save(); private void Load(int primaryKey) { this.primaryKey = primaryKey; // access the database via the repository and set someData } private IRepository repository; private int primaryKey; private string someData; } Any thoughts would be appreciated. Simon

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  • What am I not getting about this abstract class implementation?

    - by Schnapple
    PREFACE: I'm relatively inexperienced in C++ so this very well could be a Day 1 n00b question. I'm working on something whose long term goal is to be portable across multiple operating systems. I have the following files: Utilities.h #include <string> class Utilities { public: Utilities() { }; virtual ~Utilities() { }; virtual std::string ParseString(std::string const& RawString) = 0; }; UtilitiesWin.h (for the Windows class/implementation) #include <string> #include "Utilities.h" class UtilitiesWin : public Utilities { public: UtilitiesWin() { }; virtual ~UtilitiesWin() { }; virtual std::string ParseString(std::string const& RawString); }; UtilitiesWin.cpp #include <string> #include "UtilitiesWin.h" std::string UtilitiesWin::ParseString(std::string const& RawString) { // Magic happens here! // I'll put in a line of code to make it seem valid return ""; } So then elsewhere in my code I have this #include <string> #include "Utilities.h" void SomeProgram::SomeMethod() { Utilities *u = new Utilities(); StringData = u->ParseString(StringData); // StringData defined elsewhere } The compiler (Visual Studio 2008) is dying on the instance declaration c:\somepath\somecode.cpp(3) : error C2259: 'Utilities' : cannot instantiate abstract class due to following members: 'std::string Utilities::ParseString(const std::string &)' : is abstract c:\somepath\utilities.h(9) : see declaration of 'Utilities::ParseString' So in this case what I'm wanting to do is use the abstract class (Utilities) like an interface and have it know to go to the implemented version (UtilitiesWin). Obviously I'm doing something wrong but I'm not sure what. It occurs to me as I'm writing this that there's probably a crucial connection between the UtilitiesWin implementation of the Utilities abstract class that I've missed, but I'm not sure where. I mean, the following works #include <string> #include "UtilitiesWin.h" void SomeProgram::SomeMethod() { Utilities *u = new UtilitiesWin(); StringData = u->ParseString(StringData); // StringData defined elsewhere } but it means I'd have to conditionally go through the different versions later (i.e., UtilitiesMac(), UtilitiesLinux(), etc.) What have I missed here?

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  • C++ vs. C++/CLI: Const qualification of virtual function parameters

    - by James McNellis
    [All of the following was tested using Visual Studio 2008 SP1] In C++, const qualification of parameter types does not affect the type of a function (8.3.5/3: "Any cv-qualifier modifying a parameter type is deleted") So, for example, in the following class hierarchy, Derived::Foo overrides Base::Foo: struct Base { virtual void Foo(const int i) { } }; struct Derived : Base { virtual void Foo(int i) { } }; Consider a similar hierarchy in C++/CLI: ref class Base abstract { public: virtual void Foo(const int) = 0; }; ref class Derived : public Base { public: virtual void Foo(int i) override { } }; If I then create an instance of Derived: int main(array<System::String ^> ^args) { Derived^ d = gcnew Derived; } it compiles without errors or warnings. When I run it, it throws the following exception and then terminates: An unhandled exception of type 'System.TypeLoadException' occurred in ClrVirtualTest.exe Additional information: Method 'Foo' in type 'Derived'...does not have an implementation. That exception seems to indicate that the const qualification of the parameter does affect the type of the function in C++/CLI (or, at least it affects overriding in some way). However, if I comment out the line containing the definition of Derived::Foo, the compiler reports the following error (on the line in main where the instance of Derived is instantiated): error C2259: 'Derived': cannot instantiate abstract class If I add the const qualifier to the parameter of Derived::Foo or remove the const qualifier from the parameter of Base::Foo, it compiles and runs with no errors. I would think that if the const qualification of the parameter affects the type of the function, I should get this error if the const qualification of the parameter in the derived class virtual function does not match the const qualification of the parameter in the base class virtual function. If I change the type of Derived::Foo's parameter from an int to a double, I get the following warning (in addition to the aforementioned error, C2259): warning C4490: 'override': incorrect use of override specifier; 'Derived::Foo' does not match a base ref class method So, my question is, effectively, does the const qualification of function parameters affect the type of the function in C++/CLI? If so, why does this compile and why are there no errors or warnings? If not, why is an exception thrown?

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  • Operator== in derived class never gets called.

    - by Robin Welch
    Can someone please put me out of my misery with this? I'm trying to figure out why a derived operator== never gets called in a loop. To simplify the example, here's my Base and Derived class: class Base { // ... snipped bool operator==( const Base& other ) const { return name_ == other.name_; } }; class Derived : public Base { // ... snipped bool operator==( const Derived& other ) const { return ( static_cast<const Base&>( *this ) == static_cast<const Base&>( other ) ? age_ == other.age_ : false ); }; Now when I instantiate and compare like this ... Derived p1("Sarah", 42); Derived p2("Sarah", 42); bool z = ( p1 == p2 ); ... all is fine. Here the operator== from Derived gets called, but when I loop over a list, comparing items in a list of pointers to Base objects ... list<Base*> coll; coll.push_back( new Base("fred") ); coll.push_back( new Derived("sarah", 42) ); // ... snipped // Get two items from the list. Base& obj1 = **itr; Base& obj2 = **itr2; cout << obj1.asString() << " " << ( ( obj1 == obj2 ) ? "==" : "!=" ) << " " << obj2.asString() << endl; Here asString() (which is virtual and not shown here for brevity) works fine, but obj1 == obj2 always calls the Base operator== even if the two objects are Derived. I know I'm going to kick myself when I find out what's wrong, but if someone could let me down gently it would be much appreciated.

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