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  • What makes this "declarator invalid"? C++

    - by nieldw
    I have Vertex template in vertex.h. From my graph.h: 20 template<class edgeDecor, class vertexDecor, bool dir> 21 class Vertex; which I use in my Graph template. I've used the Vertex template successfully throughout my Graph, return pointers to Vertices, etc. Now for the first time I am trying to declare and instantiate a Vertex object, and gcc is telling me that my 'declarator' is 'invalid'. How can this be? 81 template<class edgeDecor, class vertexDecor, bool dir> 82 Graph<edgeDecor,int,dir> Graph<edgeDecor,vertexDecor,dir>::Dijkstra(vertex s, bool print = false) const 83 { 84 /* Construct new Graph with apropriate decorators */ 85 Graph<edgeDecor,int,dir> span = new Graph<edgeDecor,int,dir>(); 86 span.E.reserve(this->E.size()); 87 88 typename Vertex<edgeDecor,int,dir> v = new Vertex(INT_MAX); 89 span.V = new vector<Vertex<edgeDecor,int,dir> >(this->V.size,v); 90 }; And gcc is saying: graph.h: In member function ‘Graph<edgeDecor, int, dir> Graph<edgeDecor, vertexDecor, dir>::Dijkstra(Vertex<edgeDecor, vertexDecor, dir>, bool) const’: graph.h:88: error: invalid declarator before ‘v’ graph.h:89: error: ‘v’ was not declared in this scope I know this is probably another noob question, but I'll appreciate any help.

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  • Dynamically adding controls from an Event after Page_Init

    - by GenericTypeTea
    Might seem like a daft title as you shouldn't add dynamic controls after Page_Init if you want to maintain ViewState, but I couldn't think of a better way of explaining the problem. I have a class similar to the following: public class WebCustomForm : WebControl, IScriptControl { internal CustomRender Content { get { object content = this.Page.Session[this.SESSION_CONTENT_TRACKER]; return content as CustomRender; } private set { this.Page.Session[this.SESSION_CONTENT_TRACKER] = value; } } } CustomRender is an abstract class that implements ITemplate that I use to self-contain a CustomForms module I'm in the middle of writing. On the Page_Init of the page that holds the WebCustomForm, I Initialise the control by passing the relevant Ids to it. Then on the overridden OnInit method of the WebCustomForm I call the Instantiate the CustomRender control that's currently active: if (this.Content != null) { this.Content.InstantiateIn(this); } The problem is that my CustomRender controls need the ability to change the CustomRender control of the WebCustomForm. But when the events that fire on the CustomRender fire, the Page_Init event has obviously already gone off. So, my question is, how can I change the content of the WebCustomForm from a dynamically added control within it? The way I see it, I have two options: I separate the CustomRender controls out into their own stand alone control and basically have an aspx page per control and handle the events myself on the page (although I was hoping to just make a control I drop on the page and forget about) I don't use events and just keep requesting the current page, but with different Request Parameters Or I go back to the drawing board with any better suggetions anyone can give me.

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  • A bit confused about OOP and PHP.

    - by Pirkka
    Hello I have programmed with procedural style a lot before and in these few months I have decided to go OOP. Im a bit confused about OOP and PHP. Lets say I have Categories table and Pages table in my database. I would like to do a page-class and a category-class. Lets say I would have a page that showed information about the category and there would be a list of pages that belong to the category. How would I implement that in OOP way? I have thought that the category class would have a property (array) that would contain all the pages that it has. Well then comes the part that I`m confused about. Should I have a method that would get all the pages with correct categoryID from the database and should I instantiate all the rows as an Page-object? Or should I have a setPages-method in the Category-class and getAllPages-method in the Pages-class and with that method I would set all the pages to the Category-class. Huh Im lost. :D

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  • Working with extra fields in an Inline form - save_model, save_formset, can't make sense of the diff

    - by magicrebirth
    Suppose I am in the usual situation where there're extra fields in the many2many relationship: class Person(models.Model): name = models.CharField(max_length=128) class Group(models.Model): name = models.CharField(max_length=128) members = models.ManyToManyField(Person, through='Membership') class Membership(models.Model): person = models.ForeignKey(Person) group = models.ForeignKey(Group) date_joined = models.DateField() invite_reason = models.CharField(max_length=64) # other models which are unrelated to the ones above.. class Trip(models.Model): placeVisited = models.ForeignKey(Place) visitor = models.ForeignKey(Person) pleasuretrip = models.Boolean() class Place(models.Model): name = models.CharField(max_length=128) I want to add some extra fields in the Membership form that gets displayed through the Inline. These fields basically are a shortcut to the instantiation of another model (Trip). Trip can have its own admin views, but these shortcuts are needed because when my project partners are entering 'Membership' data in the system they happen to have also the 'Trip' information handy (and also because some of the info in Membership can just be copied over to Trip etc. etc.). So all I want to have is two extra fields in the Membership Inline - placeVisited and pleasuretrip - which together with the Person instance will let me instantiate the Trip model in the background... I found out I can easily add extra fields to the inline view by defining my own form. But once the data have been entered, how and when to reference to them in order to perform the save operations I need to do? class MyForm(forms.ModelForm): place = forms.ModelChoiceField(required=False, queryset=Place.objects.all(), label="place",) pleasuretrip = forms.BooleanField(required=False, label="...") class MembershipInline(admin.TabularInline): model = Membership form = MyForm def save_model(self, request, obj, form, change): place = form.place pleasuretrip = form.pleasuretrip person = form.person .... # now I can create Trip instances with those data .... obj.save() class GroupAdmin(admin.ModelAdmin): model = Group .... inlines = (MembershipInline,) This doesn't seem to work... I'm also a bit puzzled by the save_formset method... maybe is that the one I should be using? Many thanks in advance for the help!!!!

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  • ASP.NET MVC 2 - How do I use an Interface as the Type for a Strongly Typed View

    - by Rake36
    I'd like to keep my concrete classes separate from my views. Without using strongly typed views, I'm fine. I just use a big parameter list in the controller method signatures and then use my service layer factory methods to create my concrete objects. This is actually just fine with me, but it got me thinking and after a little playing, I realized it was literally impossible for a controller method to accept an interface as a method parameter - because it has no way of instantiating it. Can't create a strongly-typed view using an interface through the IDE either (which makes sense actually). So my question. Is there some way to tell the controller how to instantiate the interface parameter using my service layer factory methods? I'd like to convert from: [Authorize] [AcceptVerbs(HttpVerbs.Post)] [UrlRoute(Path = "Application/Edit/{id}")] public ActionResult Edit(String id, String TypeCode, String TimeCode, String[] SelectedSchoolSystems, String PositionChoice1, String PositionChoice2, String PositionChoice3, String Reason, String LocationPreference, String AvailableDate, String RecipientsNotSelected, String RecipientsSelected) { //New blank app IApplication _application = ApplicationService.GetById(id); to something like [Authorize] [AcceptVerbs(HttpVerbs.Post)] [UrlRoute(Path = "Application/Edit/{id}")] public ActionResult Edit(String id, IApplication app) { //Don't need to do this anymore //IApplication _application = ApplicationService.GetById(id);

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  • iPhone - adding views and landscape orientation

    - by Franz
    I got a problem with Cocoa touch and landscape orientation. I instantiate my view from a .xib; i added in my view controller - (BOOL)shouldAutorotateToInterfaceOrientation:(UIInterfaceOrientation)interfaceOrientation { return interfaceOrientation == UIInterfaceOrientationLandscapeRight; } to only allow landscape orientation. This works find for the first view i add.. if I add a second view however it is rotated again like the landscape view is shown in portrait mode (rotated 90 degree counterclockwise). I really don't know what is going on and can't find a workaround. I even tried to get behind what is happening just adding my view twice: MainMenuViewController* controller = [[MainMenuViewController alloc] initWithNibName:@"MainMenu" bundle:nil]; [window addSubview: controller.view]; MainMenuViewController* controller2 = [[MainMenuViewController alloc] initWithNibName:@"MainMenu" bundle:nil]; [window addSubview: controller2.view]; [window makeKeyAndVisible]; The view of controller is displayed correctly, while the view of controller2 is rotated by 90 degrees. Does anyone have an idea how this can happen? Thanks for your help.

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  • hadoop implementing a generic list writable

    - by Guruprasad Venkatesh
    I am working on building a map reduce pipeline of jobs(with one MR job's output feeding to another as input). The values being passed around are fairly complex, in that there are lists of different types and hash maps with values as lists. Hadoop api does not seem to have a ListWritable. Am trying to write a generic one, but it seems i can't instantiate a generic type in my readFields implementation, unless i pass in the class type itself: public class ListWritable<T extends Writable> implements Writable { private List<T> list; private Class<T> clazz; public ListWritable(Class<T> clazz) { this.clazz = clazz; list = new ArrayList<T>(); } @Override public void write(DataOutput out) throws IOException { out.writeInt(list.size()); for (T element : list) { element.write(out); } } @Override public void readFields(DataInput in) throws IOException{ int count = in.readInt(); this.list = new ArrayList<T>(); for (int i = 0; i < count; i++) { try { T obj = clazz.newInstance(); obj.readFields(in); list.add(obj); } catch (InstantiationException e) { e.printStackTrace(); } catch (IllegalAccessException e) { e.printStackTrace(); } } } } But hadoop requires all writables to have a no argument constructor to read the values back. Has anybody tried to do the same and solved this problem? TIA.

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  • java.lang.ExceptionInInitializerError Exception when creating Application Context in Spring

    - by cyotee
    I am practicing with Spring, and am getting a java.lang.ExceptionInInitializerError exception when I try to instantiate the context. The Exception appears below, with my code following it. I have simplified my experiment from before. The Exception Oct 17, 2012 5:54:22 PM org.springframework.context.support.AbstractApplicationContext prepareRefresh INFO: Refreshing org.springframework.context.support.ClassPathXmlApplicationContext@570c16b7: startup date [Wed Oct 17 17:54:22 CDT 2012]; root of context hierarchy Exception in thread "main" java.lang.ExceptionInInitializerError at org.springframework.context.support.AbstractRefreshableApplicationContext.createBeanFactory(AbstractRefreshableApplicationContext.java:195) at org.springframework.context.support.AbstractRefreshableApplicationContext.refreshBeanFactory(AbstractRefreshableApplicationContext.java:128) at org.springframework.context.support.AbstractApplicationContext.obtainFreshBeanFactory(AbstractApplicationContext.java:535) at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:449) at org.springframework.context.support.ClassPathXmlApplicationContext.<init>(ClassPathXmlApplicationContext.java:139) at org.springframework.context.support.ClassPathXmlApplicationContext.<init>(ClassPathXmlApplicationContext.java:83) at helloworld.HelloWorldTest.main(HelloWorldTest.java:13) Caused by: java.lang.NullPointerException at org.springframework.beans.factory.support.DefaultListableBeanFactory.<clinit>(DefaultListableBeanFactory.java:105) ... 7 more My configuration XML <?xml version="1.0" encoding="UTF-8"?> <beans xmlns="http://www.springframework.org/schema/beans" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:c="http://www.springframework.org/schema/c" xmlns:p="http://www.springframework.org/schema/p" xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-3.1.xsd"> <bean id="messageContainer" class="helloworld.MessageContainer"> <property name="message" value="Hello World"> </property> </bean> <bean id="messageOutputService" class="helloworld.MessageOutputService"> </bean> My test class. package helloworld; import org.springframework.context.ApplicationContext; import org.springframework.context.support.ClassPathXmlApplicationContext; public class HelloWorldTest { /** * @param args */ public static void main(String[] args) { ApplicationContext context = new ClassPathXmlApplicationContext("HelloWorldTest-context.xml"); MessageContainer message = context.getBean(MessageContainer.class); MessageOutputService service = context.getBean(MessageOutputService.class); service.outputMessageToConsole(message); } }

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  • What happens when we combine RAII and GOTO ?

    - by Robert Gould
    I'm wondering, for no other purpose than pure curiosity (because no one SHOULD EVER write code like this!) about how the behavior of RAII meshes with the use of Goto (lovely idea isn't it). class Two { public: ~Two() { printf("2,"); } }; class Ghost { public: ~Ghost() { printf(" BOO! "); } }; void foo() { { Two t; printf("1,"); goto JUMP; } Ghost g; JUMP: printf("3"); } int main() { foo(); } When running the following code in VS2005 I get the following output: 1,2,3 BOO! However I imagined, guessed, hoped that 'BOO!' wouldn't actually appear as the Ghost should have never been instantiated (IMHO, because I don't know the actual expected behavior of this code). Any Guru out there knows what's up? Just realized that if I instantiate an explicit constructor for Ghost the code doesn't compile... class Ghost { public: Ghost() { printf(" HAHAHA! "); } ~Ghost() { printf(" BOO! "); } }; Ah, the mystery ...

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  • UIAlertView choice causing resignFirstResponder to fail

    - by Chazbot
    Hi everyone. I'm having a similar issue to Anthony Chan's question, and after trying every suggested solution, I'm still stuck. Somehow, only after interacting with my UIAlertView, I'm unable to dismiss the keyboard in another view of my app. It's as though the Alert is breaking my UITextField's ability to resignFirstResponder. Below I instantiate my UIAlertView, which then calls its didDismissWIthButtonIndex method. Then, I call the showInfo method, which loads another UIViewController. UIAlertView *emailFailAlert = [[UIAlertView alloc] initWithTitle:@"Error" message:@"error message text." delegate:self cancelButtonTitle:@"Not now" otherButtonTitles:@"Settings", nil]; [emailFailAlert setTag:2]; [emailFailAlert show]; [emailFailAlert release]; Once the 'Settings' option is pressed, I'm calling this method: - (void)alertView:(UIAlertView *)alertView didDismissWithButtonIndex:(NSInteger)buttonIndex { if ([alertView tag] == 2) { if (buttonIndex == 1){ [self showInfo:nil]; } } } My showInfo method loads the other ViewController, via the code below: - (IBAction)showInfo:(id)sender { FlipsideViewController *fscontroller = [[FlipsideViewController alloc] initWithNibName:@"FlipsideView" bundle:nil]; fscontroller.delegate = self; fscontroller.modalTransitionStyle = UIModalTransitionStyleFlipHorizontal; [self presentModalViewController:fscontroller animated:YES]; [fscontroller release]; } Upon clicking any textField in this Flipside VC, I'm unable to dismiss the keyboard as I normally can with - (BOOL)textFieldShouldReturn:(UITextField *)textField, and [textField resignFirstResponder]. I've omitted this code bc this question is getting long, but I'm happy to post if necessary. The interesting part is that if I comment out the [self showInfo:nil] call made when the button is clicked and call it by clicking a test button (outside the alertView didDismissWithButtonIndex: method), everything works fine. Any idea what's happening here? Thanks in advance!

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  • Security Exception when using Custom ASP.NET Healthmonitoring event in medium trust

    - by Elementenfresser
    Hi, I'm using custom healthmonitoring events in ASP.NET We recently moved to a new server with default High Trust Permissions. Literature says that healthmonitoring and custom events should work under Medium or higher trust (http://msdn.microsoft.com/en-us/library/bb398933.aspx). Problem is - it doesn't. In less than full trust I get a SecurityException saying The application attempted to perform an operation not allowed by the security policy It works in Full trust or when I remove the inheritance of System.Web.Management.WebErrorEvent. Any suggestions anyone? Here is the super simple code behind with a custom event defined: public partial class Default : System.Web.UI.Page { protected void Page_Load(object sender, EventArgs e) { try { CallCustomEvent(); } catch (Exception ex) { Response.Write(ex.Message); throw ex; } } /// <summary> /// this metho is never called due to lacking permissions... /// </summary> private void CallCustomEvent() { try { //do something useful here } catch (Exception) { //code to instantiate the forbidden inheritance... WebBaseEvent.Raise(new CustomEvent()); } } } /// <summary> /// custom error inheriting WebErrorEvent which is not allowed in high trust? can't believe that... /// </summary> public class CustomEvent : WebErrorEvent { public CustomEvent() : base("test", HttpContext.Current.Request, 100001, new ApplicationException("dummy")) { } } and the Web Config excerpt for high trust: <system.web> <trust level="High" originUrl="" />

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  • MFC CDialog not showing

    - by Jesus_21
    here is my problem : In my Solution, I have 2 projects, one is a lib in which I created a ressource file (mylib.rc) and a dialog template in it. Then I made a class which inherits CDialog and uses this template. But when I instantiate it and call DoModal(), nothing appends... here the code of my class, is something wrong with it ? MyDialog.h /*MyDialog.h*/ #pragma once #include "../../../resource.h" class MyDialog : public CDialog { enum {IDD=IDD_DLGTEMPLATE}; public: MyDialog(CWnd* pParent = NULL); virtual ~MyDialog(); protected: virtual BOOL OnInitDialog(); DECLARE_MESSAGE_MAP() private: afx_msg void OnBnClickedOk(); afx_msg void OnBnClickedCancel(); }; MyDialog.cpp /*MyDialog.cpp*/ #include "stdafx.h" #include "MyDialog.h" MyDialog::MyDialog(CWnd* pParent /*=NULL*/) : CDialog(IDD_DLGTEMPLATE, pParent) {} MyDialog::~MyDialog() {} BOOL MyDialog::OnInitDialog() { return TRUE; } BEGIN_MESSAGE_MAP(MyDialog, CDialog) ON_BN_CLICKED(IDOK, &MyDialog::OnBnClickedOk) ON_BN_CLICKED(IDCANCEL, &MyDialog::OnBnClickedCancel) END_MESSAGE_MAP() void MyDialog::OnBnClickedOk() { OnOK(); } void MyDialog::OnBnClickedCancel() { OnCancel(); }

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  • Is it possible to restrict instantiation of an object to only one other (parent) object in VB.NET?

    - by Casey
    VB 2008 .NET 3.5 Suppose we have two classes, Order and OrderItem, that represent some type of online ordering system. OrderItem represents a single line item in an Order. One Order can contain multiple OrderItems, in the form of a List(of OrderItem). Public Class Order Public Property MyOrderItems() as List(of OrderItem) End Property End Class It makes sense that an OrderItem should not exist without an Order. In other words, an OrderItem class should not be able to be instantiated on its own, it should be dependent on an Order class to contain it and instantiate it. However, the OrderItem should be public in scope so that it's properties are accessible to other objects. So, the requirements for OrderItem are: Can not be instantiated as a stand alone object; requires Order to exist. Must be public so that any other object can access it's properties/methods through the Order object. e.g. Order.OrderItem(0).ProductID. OrderItem should be able to be passed to other subs/functions that will operate on it. How can I achieve these goals? Is there a better approach?

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  • Issue calling superclass method in subclass constructor

    - by stormin986
    I get a NullPointerException calling a Superclass Method in Subclass Inner Class Constructor... What's the Deal? In my application's main class (subclass of Application), I have a public inner class that simply contains 3 public string objects. In the parent class I declare an object of that inner class. public class MainApplication extends Application { public class Data { public String x; public String y; public String z; } private Data data; MainApplication() { data = new Data() data.x = SuperClassMethod(); } } After I instantiate the object in the constructor, I get a runtime error when I try to assign a value in the inner class with a superclass method. Any idea what's up here?? Can you not call superclass methods in the subclass constructor? ** Edit ** Original question was about inner class member assignment in outer class constructor. Turned out the issue was with calling a superclass method in the class's constructor. It was giving me a null pointer exception. Thus, the question has changed.

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  • Castle, sharing a transient component between a decorator and a decorated component

    - by Marius
    Consider the following example: public interface ITask { void Execute(); } public class LoggingTaskRunner : ITask { private readonly ITask _taskToDecorate; private readonly MessageBuffer _messageBuffer; public LoggingTaskRunner(ITask taskToDecorate, MessageBuffer messageBuffer) { _taskToDecorate = taskToDecorate; _messageBuffer = messageBuffer; } public void Execute() { _taskToDecorate.Execute(); Log(_messageBuffer); } private void Log(MessageBuffer messageBuffer) {} } public class TaskRunner : ITask { public TaskRunner(MessageBuffer messageBuffer) { } public void Execute() { } } public class MessageBuffer { } public class Configuration { public void Configure() { IWindsorContainer container = null; container.Register( Component.For<MessageBuffer>() .LifeStyle.Transient); container.Register( Component.For<ITask>() .ImplementedBy<LoggingTaskRunner>() .ServiceOverrides(ServiceOverride.ForKey("taskToDecorate").Eq("task.to.decorate"))); container.Register( Component.For<ITask>() .ImplementedBy<TaskRunner>() .Named("task.to.decorate")); } } How can I make Windsor instantiate the "shared" transient component so that both "Decorator" and "Decorated" gets the same instance? Edit: since the design is being critiqued I am posting something closer to what is being done in the app. Maybe someone can suggest a better solution (if sharing the transient resource between a logger and the true task is considered a bad design)

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  • Accessing a Class Member from a First-Class Function

    - by dbyrne
    I have a case class which takes a list of functions: case class A(q:Double, r:Double, s:Double, l:List[(Double)=>Double]) I have over 20 functions defined. Some of these functions have their own parameters, and some of them also use the q, r, and s values from the case class. Two examples are: def f1(w:Double) = (d:Double) => math.sin(d) * w def f2(w:Double, q:Double) = (d:Double) => d * q * w The problem is that I then need to reference q, r, and s twice when instantiating the case class: A(0.5, 1.0, 2.0, List(f1(3.0), f2(4.0, 0.5))) //0.5 is referenced twice I would like to be able to instantiate the class like this: A(0.5, 1.0, 2.0, List(f1(3.0), f2(4.0))) //f2 already knows about q! What is the best technique to accomplish this? Can I define my functions in a trait that the case class extends? EDIT: The real world application has 7 members, not 3. Only a small number of the functions need access to the members. Most of the functions don't care about them.

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  • C++: best way to implement globally scoped data

    - by bobobobo
    I'd like to make program-wide data in a C++ program, without running into pesky LNK2005 errors when all the source files #includes this "global variable repository" file. I have 2 ways to do it in C++, and I'm asking which way is better. The easiest way to do it in C# is just public static members. C#: public static class DataContainer { public static Object data1 ; public static Object data2 ; } In C++ you can do the same thing C++ global data way#1: class DataContainer { public: static Object data1 ; static Object data2 ; } ; Object DataContainer::data1 ; Object DataContainer::data2 ; However there's also extern C++ global data way #2: class DataContainer { public: Object data1 ; Object data2 ; } ; extern DataContainer * dataContainer ; // instantiate in .cpp file In C++ which is better, or possibly another way which I haven't thought about? The solution has to not cause LNK2005 "object already defined" errors.

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  • A dynamic array of a class, inside another separate class?

    - by pinnacler
    I'm working on a robot localization simulator and I created a class called "landmark". The end result is going to be a robot that is always centered and always faces the top of the screen. As it turns, the birds eye view map will rotate around the robot. To accomplish this, I'm assuming I can rotate one class and have all elements inside rotate as well. So, the landmark class has properties x,y, label, and radius. This is suppose to simulate a tree location in a forest. To test everything, I need "forest data," and I wrote a script to generate 100 trees in a 100m x 100m area. The script automatically generates values within an acceptable range for x,y, radius. The generated data is stored in an object called tempForest and is 100x3. Ideally, I want to create a class called "landmarks" (plural) that has 100 landmark instances inside. How would I instantiate 100 instances of landmark in one instance of landmarks using that randomly generated data? Ideally, I'd just type treeBeacons = landmarks(); and it would randomly populate 100 (user definable, set in config file) instances with x, y, radius data. I'm not sure how to deal with a dynamic array of class "Landmark", inside another single class "landmarks." Any ideas?

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  • how do use Ninject with class libraries I am developing?

    - by Greg
    Hi, If I am working on a class library how do I make use of Ninject here? Ie from the internal class library point of view and also from the client code? For example: should the class library have it's own IOC set up, or should it always assume the client code will supply? if no (ie it's upto the client to have the IOC in place) then where is the mapping data stored here'. Is this mapping of the class library's functionality to be places in the client? have a reusable library that is available, that uses interfaces with classes that use the getInstance concept to create concrete classes for you to use, then in this case would that make sense on the client side to use the IOC container to create instances of these classes? Or is that really applying a double layer of abstraction? Q2 Or in the cases where I'm building the reusable library myself and want the client to use an IOC container, then in my reusable library would I then dispense with any overhead of having factories or "getInstance" methods to instantiate the classes in the client? (i.e. as the IOC container would do this no?)

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  • Is dependency injection only for service type objects and singletons? (and NOT for gui?)

    - by sensui
    I'm currently experimenting with the Google's guice inversion of control container. I previously had singletons for just about any service (database, active directory) my application used. Now I refactored the code: all the dependencies are given as parameters to constructors. So far, so good. Now the hardest part is with the graphical user interface. I face this problem: I have a table (JTable) of products wrapped in an ProductFrame. I give the dependencies as parameters (EditProductDialog). @Inject public ProductFrame(EditProductDialog editProductDialog) { // ... } // ... @Inject public EditProductDialog(DBProductController productController, Product product) { // ... } The problem is that guice can't know what Product I have selected in the table, so it can't know what to inject in the EditProductDialog. Dependency Injection is pretty viral (if I modify one class to use dependency injection I also need to modify all the other classes it interacts with) so my question is should I directly instantiate EditProductDialog? But then I would have to pass manually the DBProductController to the EditProductDialog and I will also need to pass it to the ProductFrame and all this boils down to not using dependency injection at all. Or is my design flawed and because of that I can't really adapt the project to dependecy injection? Give me some examples of how you used dependency injection with the graphical user interface. All the examples found on the Internet are really simple examples where you use some services (mostly databases) with dependency injection.

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  • Trying to create a .NET DLL to be used with Non-.NET Application

    - by Changeling
    I am trying to create a .NET DLL so I can use the cryptographic functions with my non .NET application. I have created a class library so far with this code: namespace AESEncryption { public class EncryptDecrypt { private static readonly byte[] optionalEntropy = { 0x21, 0x05, 0x07, 0x08, 0x27, 0x02, 0x23, 0x36, 0x45, 0x50 }; public interface IEncrypt { string Encrypt(string data, string filePath); }; public class EncryptDecryptInt:IEncrypt { public string Encrypt(string data, string filePath) { byte[] plainKey; try { // Read in the secret key from our cipher key store byte[] cipher = File.ReadAllBytes(filePath); plainKey = ProtectedData.Unprotect(cipher, optionalEntropy, DataProtectionScope.CurrentUser); // Convert our plaintext data into a byte array byte[] plainTextBytes = Encoding.ASCII.GetBytes(data); MemoryStream ms = new MemoryStream(); Rijndael alg = Rijndael.Create(); alg.Mode = CipherMode.CBC; alg.Key = plainKey; alg.IV = optionalEntropy; CryptoStream cs = new CryptoStream(ms, alg.CreateEncryptor(), CryptoStreamMode.Write); cs.Write(plainTextBytes, 0, plainTextBytes.Length); cs.Close(); byte[] encryptedData = ms.ToArray(); return Convert.ToString(encryptedData); } catch (Exception ex) { return ex.Message; } } } } } In my VC++ application, I am using the #import directive to import the TLB file created from the DLL, but the only available functions are _AESEncryption and LIB_AES etc I don't see the interface or the function Encrypt. When I try to instantiate so I can call the functions in my VC++ program, I use this code and get the following error: HRESULT hr = CoInitialize(NULL); IEncryptPtr pIEncrypt(__uuidof(EncryptDecryptInt)); error C2065: 'IEncryptPtr': undeclared identifier error C2146: syntax error : missing ';' before identifier 'pIEncrypt'

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  • Strategies for when to use properties and when to use internal variables on internal classes?

    - by Edward Tanguay
    In almost all of my classes, I have a mixture of properties and internal class variables. I have always chosen one or the other by the rule "property if you need it externally, class variable if not". But there are many other issues which make me rethink this often, e.g.: at some point I want to use an internal variable from outside the class, so I have to refactor it into a property which makes me wonder why I don't just make all my internal variables properties in case I have to access them externally anyway, since most classes are internal classes anyway it aren't exposed on an API so it doesn't really matter if the internal variables are accessible from outside the class or not but then since C# doesn't allow you to instantiate e.g. List<string> property in the definition, then these properties have to be initialized in every possible constructor, so these variables I would rather have internal variables just to keep things cleaner in that they are all initialized in one place C# code reads more cleanly if constructor/method parameters are camel case and you assign them to pascal case properties instead of the ambiguity of seeing "templateIdCode" and having to look around to see if it is a local variable, method parameter or internal class variable, e.g. it is easier when you see "TemplateIdCode = templateIdCode" that this is a parameter being assigned to a class property. This would be an argument for always using only properties on internal classes. e.g.: public class TextFile { private string templateIdCode; private string absoluteTemplatePathAndFileName; private string absoluteOutputDirectory; private List<string> listItems = new List<string>(); public string Content { get; set; } public List<string> ReportItems { get; set; } public TextFile(string templateIdCode) { this.templateIdCode = templateIdCode; ReportItems = new List<string>(); Initialize(); } ... When creating internal (non-API) classes, what are your strategies in deciding if you should create an internal class variable or a property?

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  • Java: creating objects of arrays with different names at runtime and accessing/updating them

    - by scriptingalias
    Hello, I'm trying to create a class that can instantiate arrays at runtime by giving each array a "name" created by the createtempobjectname() method. I'm having trouble making this program run. I would also like to see how I could access specific objects that were created during runtime and accessing those arrays by either changing value or accessing them. This is my mess so far, which compiles but gets a runtime exception. import java.lang.reflect.Array; public class arrays { private static String temp; public static int name = 0; public static Object o; public static Class c; public static void main(String... args) { assignobjectname(); //getclassname();//this is supposed to get the name of the object and somehow //allow the arrays to become updated using more code? } public static void getclassname() { String s = c.getName(); System.out.println(s); } public static void assignobjectname()//this creates the object by the name returned { //createtempobjectname() try { String object = createtempobjectname(); c = Class.forName(object); o = Array.newInstance(c, 20); } catch (ClassNotFoundException exception) { exception.printStackTrace(); } } public static String createtempobjectname() { name++; temp = Integer.toString(name); return temp; } }

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  • Dependency Injection into your Singleton

    - by Langali
    I have a singleton that has a spring injected Dao (simplified below): public class MyService<T> implements Service<T> { private final Map<String, T> objects; private static MyService instance; MyDao myDao; public void set MyDao(MyDao myDao) { this. myDao = myDao; } private MyService() { this.objects = Collections.synchronizedMap(new HashMap<String, T>()); // start a background thread that runs for ever } public static synchronized MyService getInstance() { if(instance == null) { instance = new MyService(); } return instance; } public void doSomething() { myDao.persist(objects); } } My spring config will probably look like this: <bean id="service" class="MyService" factory-method="getInstance"/> But this will instantiate the MyService during startup. Is there a programmatic way to do a dependency injection of MyDao into MyService, but not have spring manage the MyService? Basically I want to be able to do this from my code: MyService.getInstance().doSomething(); while having spring inject the MyDao for me.

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  • How do I get NHibernate to work with .NET Framework 2.0?

    - by Daniel Dolz
    I can not make NHibernate 2.1 work in machines without framework 3.X (basically, windows 2000 SP4, although it happens with XP too). NHibernate doc do not mention this. Maybe you can help? I NEED to make NHibernate 2.1 work in Windows 2000 PCs, do you think this can be done? PD: DataBase is SQL 2000/2005. Error is: NHibernate.MappingException: Could not compile the mapping document: Datos.NH_VEN_ComprobanteBF.hbm.xml ---> NHibernate.HibernateException: Could not instantiate dialect class NHibernate.Dialect.MsSql2000Dialect ---> System.Reflection.TargetInvocationException: Se produjo una excepción en el destino de la invocación. ---> System.TypeInitializationException: Se produjo una excepción en el inicializador de tipo de 'NHibernate.NHibernateUtil'. ---> System.TypeLoadException: No se puede cargar el tipo 'System.DateTimeOffset' del ensamblado'mscorlib, Version=2.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089'. en NHibernate.Type.DateTimeOffsetType.get_ReturnedClass() en NHibernate.NHibernateUtil..cctor() --- Fin del seguimiento de la pila de la excepción interna --- en NHibernate.Dialect.Dialect..ctor() en NHibernate.Dialect.MsSql2000Dialect..ctor() --- Fin del seguimiento de la pila de la excepción interna --- en System.RuntimeTypeHandle.CreateInstance(RuntimeType type, Boolean publicOnly, Boolean noCheck, Boolean& canBeCached, RuntimeMethodHandle& ctor, Boolean& bNeedSecurityCheck) en System.RuntimeType.CreateInstanceSlow(Boolean publicOnly, Boolean fillCache) en System.RuntimeType.CreateInstanceImpl(Boolean publicOnly, Boolean skipVisibilityChecks, Boolean fillCache) en System.Activator.CreateInstance(Type type, Boolean nonPublic) en NHibernate.Bytecode.ActivatorObjectsFactory.CreateInstance(Type type) en NHibernate.Dialect.Dialect.InstantiateDialect(String dialectName) --- Fin del seguimiento de la pila de la excepción interna --- en NHibernate.Dialect.Dialect.InstantiateDialect(String dialectName) en NHibernate.Dialect.Dialect.GetDialect(IDictionary`2 props) en NHibernate.Cfg.Configuration.AddValidatedDocument(NamedXmlDocument doc) --- Fin del seguimiento de la pila de la excepción interna --- en NHibernate.Cfg.Configuration.LogAndThrow(Exception exception) en NHibernate.Cfg.Configuration.AddValidatedDocument(NamedXmlDocument doc) en NHibernate.Cfg.Configuration.ProcessMappingsQueue() and continues...

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