Search Results

Search found 51282 results on 2052 pages for 'empty class'.

Page 464/2052 | < Previous Page | 460 461 462 463 464 465 466 467 468 469 470 471  | Next Page >

  • Converting string to a simple type

    - by zespri
    .Net framework contains a great class named Convert that allows conversion between simple types, DateTime type and String type. Also the class support conversion of the types implementing IConvertible interface. The class has been implemented in the very first version of .Net framework. There were a few things in the first .Net framework that were not done quite right. For example .Parse methods on simple types would throw an exception if the string couldn't be parsed and there would be no way to check if exception is going to be thrown in advance. A future version of .Net Framework removed this deficiency by introducing the TryParse method that resolved this problem. The Convert class dates back to time of the old Parse method, so the ChangeType method on this class in implemented old style - if conversion can't be performed an exception is thrown. Take a look at the following code: public static T ConvertString<T>(string s, T @default) { try { return (T)Convert.ChangeType(s, typeof(T), CultureInfo.InvariantCulture); } catch (Exception) { return @default; } } This code basically does what I want. However I would pretty much like to avoid the ugly try/catch here. I'm sure, that similar to TryParse, there is a modern method of rewriting this code without the catch-all. Could you suggest one?

    Read the article

  • VC9 C1083 Cannot open include file: 'boost...' after trying to abstract an include dependency

    - by ronivek
    Hey, So I've been working on a project for the past number of weeks and it uses a number of Boost libraries. In particular I'm using the boost::dynamic_bitset library quite extensively. I've had zero issues up until now; but tonight I discovered a dependency between some includes which I had to resolve; and I tried to do so by providing an abstract callback class. Effectively I now have the following: First include... class OtherClassCallback { public: virtual int someOtherMethod() const = 0; }; class SomeClass { public: void someMethod(OtherClassCallback *oc) { ... oc->someOtherMethod(); ... } }; Second include... #include "SomeClass.h" class SomeOtherClass : public OtherClassCallback { public: int someOtherMethod() const { return this->someInt; } }; Here is the issue; ever since I implemented this class I'm now getting the following error: fatal error C1083: Cannot open include file: 'boost/dynamic_bitset/dynamic_bitset.hpp': No such file or directory Now I'm getting no other compiler errors; and it's a pretty substantial project. My include paths and so on are perfect; my files are fully accessible and removing the changes fixes the issue. Does anyone have any idea what might be going on? I'm compiling to native Windows executables in VS9. I should confess that I'm very inexperienced with C++ in general so go easy on me if it's something horribly straightforward; I can't figure it out.

    Read the article

  • How to get selenium to click on an object other than by ID

    - by Zombies
    So here is a little challenge. I have an image. It has 2 attributes: a random ID - not helpful an image url - but it is a button, and other buttons use the same image url, not helpful a CSS class - also used by too many other things to be helpful a style - neither helpful nor unique This image is however inside of an anchor tag, but the anchor tab isn't to a page, it just runs some javascript. Bellow is the html in question: <a id="template:j_id__ctru168pc2" title="Click for the Manual Class LOV" class="xei" style="text-decoration: none;" onclick="return false;" href="#"> <img id="template:j_id__ctru169pc2" class="xgs" style="border: 0pt none;" src="images/lov_ena.png"> </a> How can I click this image without using the ID?

    Read the article

  • How to use JNI, but only when available for current platform?

    - by Mecki
    What is the common way (or best practice) to optionally use JNI? E.g. I have a Java class and this class is 100% pure Java, so it can run on all platforms. However, on some platforms I'd like to speed up some heavy calculations using JNI - which works fine. Unfortunately I cannot support any existing Java platform in the world. So I guess it is fine to initially only support the big three: Linux, Windows, Mac OS X. So what I'd like to do is to use JNI on those three platforms and use the 100% pure Java version on all other platforms. Now I can think of various ways how to do that (loading class dynamically for example and either loading the JNI class or the pure Java one), but thinking that this is a common issue that thousands of projects had to solve in the past for sure, I'm really surprised to not find any documentation or references to the question how to solve this most elegantly or effectively.

    Read the article

  • AngularJS not validating email field in form

    - by idipous
    I have the html below where I have a form that I want to submit to the AngularJS Controller. <div class="newsletter color-1" id="subscribe" data-ng-controller="RegisterController"> <form name="registerForm"> <div class="col-md-6"> <input type="email" placeholder="[email protected]" data-ng-model="userEmail" required class="subscribe"> </div> <div class="col-md-2"> <button data-ng-click="register()" class="btn btn-primary pull-right btn-block">Subsbcribe</button> </div> </form> </div> And the controller is below app.controller('RegisterController', function ($scope,dataFactory) { $scope.users = dataFactory.getUsers(); $scope.register = function () { var userEmail = $scope.userEmail; dataFactory.insertUser(userEmail); $scope.userEmail = null; $scope.ThankYou = "Thank You!"; } }); The problem is that no validation is taking place when I click the button. It is always routed to the controller although I do not supply a correct email. So every time I click the button I get the {{ThankYou}} variable displayed. Maybe I do not understand something.

    Read the article

  • Qt: any way to automatically generate QSharedData-based structures?

    - by Eye of Hell
    Hello. Qt has a build-in supprt for creating objects with integrated reference counting via QSharedData and QSharedDataPointer. All wordks great, but for each such object i need to write a lot of code: QSharedData-based implementation class with constructor and copy constructor, object class itsef with accessor methods for each filed. For a simple structures with 5-10 fields this requires really lot of near same code. Is it some ways to automate such classes generation? Maybe it's some generators exists that take a short description and automatically generates implementation class and object class with all accessors?

    Read the article

  • Does C++ have a proper implementation of interface that does not use vtable?

    - by gilbertc
    Does C++ have a proper implementation of interface that does not use vtable? for example class BaseInterface{ public: virtual void func() const = 0; } class BaseInterfaceImpl:public BaseInterface{ public: void func(){ std::cout<<"called."<<endl; } } BaseInterface* obj = new BaseInterfaceImpl(); obj->func(); the call to func at the last line goes to vtable to find the func ptr of BaseInterfaceImpl::func, but is there any C++ way to do that directly as the BaseInterfaceImpl is not subclassed from any other class besides the pure interface class BaseInterface? Thanks. Gil.

    Read the article

  • Accessing the "super of this" in Java

    - by gerdemb
    This is what I'm doing now. Is there a better way to access the super class? public class SearchWidget { private void addWishlistButton() { final SearchWidget thisWidget = this; button.addClickHandler(new ClickHandler() { public void onClick(ClickEvent event) { // A better way to access the super class? // something like "this.super" ...? workWithWidget(thisWidget); } } } } I'm programming with Google Web Toolkit, but I think this is really a generic Java question.

    Read the article

  • How do i use 'auto' in C++ (C++0x) ?

    - by LoudNPossiblyRight
    What do i have to do to this code to make it compile, it's braking around this line: auto val = what.getObject(); #include<iostream> using namespace std; class CUP{ public: void whatsHappening(){} }; class MUG{ public: void whatsHappening(){} }; class CupThrower{ public: CUP cp; CUP getObject(){ return cp;} }; class MugThrower{ public: MUG mg; MUG getObject(){return mg;} }; template <typename T> void whatsHappening(T what){ auto val = what.getObject(); //DOES NOT COMPILE val.whatsHappening(); } int main(){ CupThrower ct; MugThrower mt; whatsHappening(ct); whatsHappening(mt); return 0; } i am using VS2008 to compile.

    Read the article

  • What is the problems for my xml file format ?

    - by python
    <? $xml="<?xml version='1.0' encoding='UTF-8' standalone='no'?> <Document> <pain.001.001.02> <books> <book> <qty>12</qty> <title>C++</title> </book> <book> <qty>21</qty> <title>PHP</title> </book> </books> <books> <book> <qty>25</qty> <title>Java</title> </book> <book> <qty>32</qty> <title>Python</title> </book> <book> <qty>22</qty> <title>History</title> </book> </books> </pain.001.001.02> </Document> "; $doc = new DOMDOcument; $doc->loadxml($xml); $xpath = new DOMXpath($doc); $arr = array( array( '12;C++', '21;PHP'), array( '25;Java', '32;Python' ) ); # Remove elements based on qty and title foreach($arr as $items) { foreach($items as $item) { list($qty, $title) = explode(';', $item); foreach($xpath->query('//pain.001.001.02/books/book[title="'.$title.'"][qty="'.$qty.'"]') as $book) { $book->parentNode->removeChild($book); } } } # Remove empty <books> foreach($xpath->query('pain.001.001.02/books[count(book)=0]') as $empty) { $empty->parentNode->removeChild($empty); } header('Content-type: text/xml'); echo $doc->savexml(); ?> If I put <Document> in the xml document , get the expected result BUT If change <Document> to <Document xmlns="urn:iso:std:iso:20022:tech:xsd:pain.001.001.02"> get UNEXPECTED RESULT? Do you have any idea? thanks

    Read the article

  • Documentation for Qt documentation comments? Qt + Doxygen?

    - by Jake Petroules
    Where can I find documentation for Qt documentation comments? I'm referring to how Qt uses a specific style for documentation comments, like so: /*! \class MyClassName \brief The MyClassName class is used as an example on Stack Overflow. This class serves a few functions, the most important being: \list \i So people can understand my question. \i So people can have a few laughs at the comedy in my example. \endlist */ ...you get the picture. So where can I find information about all the switches, like \class, \list, \brief, etc. Also, what tool(s) do I use to generate documentation files from these comments in my source files? Does Doxygen support this syntax?

    Read the article

  • Calling different functions depending on the template parameter c++

    - by Noman Javed
    I want to have something like that class A { public: Array& operator()() { . . . } }; class B { public: Element& operator[](int i) { ... } }; template<class T> class execute { public: output_type = operator()(T& t) { if(T == A) Array out = T()(); else { Array res; for(int i=0 ; i < length; ++i) a[i] = t[i]; } } }; There are two issues here 1. Meta-function replacing if-else in the execute operator() 2. Return type of execute operator() Thanks in anticipation Noman

    Read the article

  • Is it OK to write a constructor which does nothing?

    - by Roman
    To use methods of a class I need to instantiate a class. At the moment the class has not constructor (so I want to write it). But than I have realized that the constructor should do nothing (I do need to specify values of fields). In this context I have a question if it is OK to write constructor which does nothing. For example: public Point() { }

    Read the article

  • Why boost::recursive_mutex is not working as expected?

    - by Kjir
    I have a custom class that uses boost mutexes and locks like this (only relevant parts): template<class T> class FFTBuf { public: FFTBuf(); [...] void lock(); void unlock(); private: T *_dst; int _siglen; int _processed_sums; int _expected_sums; int _assigned_sources; bool _written; boost::recursive_mutex _mut; boost::unique_lock<boost::recursive_mutex> _lock; }; template<class T> FFTBuf<T>::FFTBuf() : _dst(NULL), _siglen(0), _expected_sums(1), _processed_sums(0), _assigned_sources(0), _written(false), _lock(_mut, boost::defer_lock_t()) { } template<class T> void FFTBuf<T>::lock() { std::cerr << "Locking" << std::endl; _lock.lock(); std::cerr << "Locked" << std::endl; } template<class T> void FFTBuf<T>::unlock() { std::cerr << "Unlocking" << std::endl; _lock.unlock(); } If I try to lock more than once the object from the same thread, I get an exception (lock_error): #include "fft_buf.hpp" int main( void ) { FFTBuf<int> b( 256 ); b.lock(); b.lock(); b.unlock(); b.unlock(); return 0; } This is the output: sb@dex $ ./src/test Locking Locked Locking terminate called after throwing an instance of 'boost::lock_error' what(): boost::lock_error zsh: abort ./src/test Why is this happening? Am I understanding some concept incorrectly?

    Read the article

  • C#. Saving information about events and event handlers and removing handlers using this information

    - by Philipp
    I have an object which is creating several event handlers using lambda expressions, and I need to remove all handlers created in that object in one time. I'm trying to create some unified static object which will 'know' which handler relates to which object and event if event handler was created through this static object. I tried something like code below, but I don't understand how to save events and event handlers objects, to be able remove handlers in one time. class Program { static void Main(string[] args) { var EventSender = new EventSender(); var EventReceiver = new EventReceiver(EventSender); EventSender.Invoke(" some var "); LinkSaver.RemoveEvent(EventReceiver); // ?? Console.ReadKey(); } } public class ObjLink{ public object Event; public object Action; } public static class LinkSaver { public static void SetEvent<T>(object obj, Action<T> Event, T Action) { Event(Action); var objLink = new ObjLink{Event = Event, Action = Action}; if (!Links.ContainsKey(obj)) Links.Add(obj, new List<ObjLink>{objLink}); else Links[obj].Add(objLink); } static Dictionary<object,List<ObjLink>> Links = new Dictionary<object, List<ObjLink>>(); public static void RemoveEvent(object obj){ foreach(var objLink in Links[obj]){ // objLink.Event -= objLink.Action; ??? } } } public class EventReceiver { public EventReceiver(EventSender obj) { LinkSaver.SetEvent<EventSender.TestDelegate>(this, obj.SetEvent, str => Console.WriteLine(str + " test event!")); } } public class EventSender { public void Invoke(string var) { if (eventTest != null) eventTest(var); } public void SetEvent(TestDelegate Action) { eventTest += Action; } public delegate void TestDelegate(string var); private event TestDelegate eventTest; // by the way public void RemoveFromEvent() { foreach (var handler in eventTest.GetInvocationList()) eventTest -= (TestDelegate)handler; } }

    Read the article

  • Speed comparison - Template specialization vs. Virtual Function vs. If-Statement

    - by Person
    Just to get it out of the way... Premature optimization is the root of all evil Make use of OOP etc. I understand. Just looking for some advice regarding the speed of certain operations that I can store in my grey matter for future reference. Say you have an Animation class. An animation can be looped (plays over and over) or not looped (plays once), it may have unique frame times or not, etc. Let's say there are 3 of these "either or" attributes. Note that any method of the Animation class will at most check for one of these (i.e. this isn't a case of a giant branch of if-elseif). Here are some options. 1) Give it boolean members for the attributes given above, and use an if statement to check against them when playing the animation to perform the appropriate action. Problem: Conditional checked every single time the animation is played. 2) Make a base animation class, and derive other animations classes such as LoopedAnimation and AnimationUniqueFrames, etc. Problem: Vtable check upon every call to play the animation given that you have something like a vector<Animation>. Also, making a separate class for all of the possible combinations seems code bloaty. 3) Use template specialization, and specialize those functions that depend on those attributes. Like template<bool looped, bool uniqueFrameTimes> class Animation. Problem: The problem with this is that you couldn't just have a vector<Animation> for something's animations. Could also be bloaty. I'm wondering what kind of speed each of these options offer? I'm particularly interested in the 1st and 2nd option because the 3rd doesn't allow one to iterate through a general container of Animations. In short, what is faster - a vtable fetch or a conditional?

    Read the article

  • Robotlegs: Warning: Injector already has a rule for type

    - by MikeW
    I have a bunch of warning messages like this appear when using Robotlegs/Signals. Everytime this command class executes, which is every 2-3 seconds ..this message displays below If you have overwritten this mapping intentionally you can use "injector.unmap()" prior to your replacement mapping in order to avoid seeing this message. Warning: Injector already has a rule for type "mx.messaging.messages::IMessage", named "". The command functions fine otherwise but I think I'm doing something wrong anyhow. public class MessageReceivedCommand extends SignalCommand { [Inject] public var message:IMessage; ...etc.. do something with message.. } the application context doesnt map IMessage to this command, as I only see an option to mapSignalClass , besides the payload is received fine. Wonder if anyone knows how I might either fix or suppress this message. I've tried calling this as the warning suggests injector.unmap(IMessage, "") but I receive an error - no mapping found for ::IMessage named "". Thanks Edit: A bit more info about the error Here is the signal that I dispatch to the command public class GameMessageSignal extends Signal { public function GameMessageSignal() { super(IMessage); } } which is dispatched from a IPushDataService class gameMessage.dispatch(message.message); and the implementation is wired up in the app context via injector.mapClass(IPushDataService, PushDataService); along with the signal signalCommandMap.mapSignalClass(GameMessageSignal, MessageReceivedCommand); Edit #2: Probably good to point out also I inject an instance of GameMessageSignal into IPushDataService public class PushDataService extends BaseDataService implements IPushDataService { [Inject] public var gameMessage:GameMessageSignal; //then private function processMessage(message:MessageEvent):void { gameMessage.dispatch(message.message); } } Edit:3 The mappings i set up in the SignalContext: injector.mapSingleton(IPushDataService); injector.mapClass(IPushDataService, PushDataService);

    Read the article

  • How can I login to a website with Python?

    - by Shady
    How can I do it? I was trying to enter some specified link (with urllib), but to do it, I need to log in. I have this source from the site: <form id="login-form" action="auth/login" method="post"> <div> <!--label for="rememberme">Remember me</label><input type="checkbox" class="remember" checked="checked" name="remember me" /--> <label for="email" id="email-label" class="no-js">Email</label> <input id="email-email" type="text" name="handle" value="" autocomplete="off" /> <label for="combination" id="combo-label" class="no-js">Combination</label> <input id="password-clear" type="text" value="Combination" autocomplete="off" /> <input id="password-password" type="password" name="password" value="" autocomplete="off" /> <input id="sumbitLogin" class="signin" type="submit" value="Sign In" /> Is this possible?

    Read the article

  • JUnit for Functions with Void Return Values

    - by RobotNerd
    I've been working on a Java application where I have to use JUnit for testing. I am learning it as I go. So far I find it to be useful, especially when used in conjunction with the Eclipse JUnit plugin. After playing around a bit, I developed a consistent method for building my unit tests for functions with no return values. I wanted to share it here and ask others to comment. Do you have any suggested improvements or alternative ways to accomplish the same goal? Common Return Values First, there's an enumeration which is used to store values representing test outcomes. public enum UnitTestReturnValues { noException, unexpectedException // etc... } Generalized Test Let's say a unit test is being written for: public class SomeClass { public void targetFunction (int x, int y) { // ... } } The JUnit test class would be created: import junit.framework.TestCase; public class TestSomeClass extends TestCase { // ... } Within this class, I create a function which is used for every call to the target function being tested. It catches all exceptions and returns a message based on the outcome. For example: public class TestSomeClass extends TestCase { private UnitTestReturnValues callTargetFunction (int x, int y) { UnitTestReturnValues outcome = UnitTestReturnValues.noException; SomeClass testObj = new SomeClass (); try { testObj.targetFunction (x, y); } catch (Exception e) { UnitTestReturnValues.unexpectedException; } return outcome; } } JUnit Tests Functions called by JUnit begin with a lowercase "test" in the function name, and they fail at the first failed assertion. To run multiple tests on the targetFunction above, it would be written as: public class TestSomeClass extends TestCase { public void testTargetFunctionNegatives () { assertEquals ( callTargetFunction (-1, -1), UnitTestReturnValues.noException); } public void testTargetFunctionZeros () { assertEquals ( callTargetFunction (0, 0), UnitTestReturnValues.noException); } // and so on... } Please let me know if you have any suggestions or improvements. Keep in mind that I am in the process of learning how to use JUnit, so I'm sure there are existing tools available that might make this process easier. Thanks!

    Read the article

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

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

    Read the article

  • Visual Studio Default Open File Action

    - by Kleinux
    I am using Visual Studio 2008 with C#. Is there a way to set the default editor for a class file containing a DataTable derived class? Whenever I double click on one of these classes to open the file VS attempts to open a component designer. Since my class isn't compatible with that editor this is a rather useless default. I would like these files to open up in the normal code editor.

    Read the article

  • Is it okay for multiple objects to retain the same object in Objective-C/Cocoa?

    - by Andrew Arrow
    Say I have a tableview class that lists 100 Foo objects. It has: @property (nonatomic, retain) NSMutableArray* fooList; and I fill it up with Foos like: self.fooList = [NSMutableArray array]; while (something) { Foo* foo = [[Foo alloc] init]; [fooList addObject:foo]; [foo release]; } First question: because the NSMutableArray is marked as retain, that means all the objects inside it are retained too? Am I correctly adding the foo and releasing the local copy after it's been added to the array? Or am I missing a retain call? Then if the user selects one specific row in the table and I want to display a detail Foo view I call: FooView* localView = [[FooView alloc] initWithFoo:[self.fooList objectAtIndex:indexPath.row]]; [self.navigationController pushViewController:localView animated:YES]; [localView release]; Now the FooView class has: @property (nonatomic, retain) Foo* theFoo; so now BOTH the array is holding on to that Foo as well as the FooView. But that seems okay right? When the user hits the back button dealloc will be called on FooView and [theFoo release] will be called. Then another back button is hit and dealloc is called on the tableview class and [fooList release] is called. You might argue that the FooView class should have: @property (nonatomic, assign) Foo* theFoo; vs. retain. But sometimes the FooView class is called with a Foo that's not also in an array. So I wanted to make sure it was okay to have two objects holding on to the same other object.

    Read the article

  • Dynamic, reflective SignalHandler in Java

    - by pilcrow
    How do I install signal handling logic iff sun.misc.Signal is available? Background First generation of my code looked something like this: class MyApp { public static void main(String[] args) { ... Signal.handle(term_sig, new SignalHandler() { public void handle(Signal sig) { ... } }); ... } } I believe I understand how to reflectively test for and use signal handlers -- Class.forName("sun.misc.Signal"), reflectively call Signal.handle, and so forth. My impulse was simply to instantiate another anonymous inner class with the dynamically obtained SignalHandler class, but I think that's just wishful syntax.

    Read the article

  • Storing object into cache using Linq classes and velocity

    - by Arun
    I careated couple of linq classes & marked the datacontext as unidirectional. Out of four classes; one is main class while other three are having the one to many relationship with first one; When I load the object of main class & put into the memory OR serialize it into an XML file; I never get the child class data while it is maked as DataContractAttribute. How can I force object to put the child class data into XML file or into cache ?

    Read the article

  • PHP Fatal error on line number that doesn't exist

    - by alexantd
    Fatal error: Allowed memory size of 134217728 bytes exhausted (tried to allocate 523800 bytes) in /Library/WebServer/Documents/XMLDataStore.class.php on line 981 The curious thing about this error is not the memory leak, which would be easy enough to troubleshoot. Rather, it is the fact that XMLDataStore.class.php is only 850 lines long, which I have verified in multiple text editors. This is with the PHP 5.3 bundled with Snow Leopard. I'm not using an opcode cache. Here is my php.ini: allow_url_fopen = Off error_reporting = -1 display_errors = 1 display_startup_errors = 1 date.timezone = 'America/Los_Angeles' output_buffering = Off realpath_cache_size = 0k XMLDataStore.class.php has recently been refactored and it used to be longer than 981 lines. It's almost as if PHP has cached a 2-week-old version and is reading that. I'm positive that the current version at /Library/WebServer/Documents/XMLDataStore.class.php is only 850 lines long, though.

    Read the article

< Previous Page | 460 461 462 463 464 465 466 467 468 469 470 471  | Next Page >