Search Results

Search found 17407 results on 697 pages for 'static constructor'.

Page 33/697 | < Previous Page | 29 30 31 32 33 34 35 36 37 38 39 40  | Next Page >

  • C#: why have all static methods/variables in a non-static class?

    - by Craig Johnston
    I have come across a class which is non-static, but all the methods and variables are static. Eg: public class Class1 { private static string String1 = "one"; private static string String2 = "two"; public static void PrintStrings(string str1, string str2) { ... All the variables are static across all instances, so there is no point having separate instances of the class. Is there any reason to create a class such as this?

    Read the article

  • How can I create a generic constructor? (ie. BaseClass.FromXml(<param>)

    - by SofaKng
    I'm not sure how to describe this but I'm trying to create a base class that contains a shared (factory) function called FromXml. I want this function to instantiate an object of the proper type and then fill it via an XmlDocument. For example, let's say I have something like this: Public Class XmlObject Public Shared Function FromXml(ByVal source as XmlDocument) As XmlObject // <need code to create SPECIFIC TYPE of object and return it End Function End Class Public Class CustomObject Inherits XmlObject End Class I'd like to be able to do something like this: Dim myObject As CustomObject = CustomObject.FromXml(source) Is this possible?

    Read the article

  • How to use a object whose copy constructor and copy assignment is private?

    - by coanor
    In reading TCPL, I got a problem, as the title refered, and then 'private' class is: class Unique_handle { private: Unique_handle& operator=(const Unique_handle &rhs); Unique_handle(const Unique_handle &rhs); public: //... }; the using code is: struct Y { //... Unique_handle obj; }; and I want to execute such operations: int main() { Y y1; Y y2 = y1; } although, these code are come from TCPL, but I still can not got the solution... Can anybody help me, appreciate.

    Read the article

  • Definition of variables/fields type within a constructor, how is it done?

    - by elementz
    I just had a look at Suns Java tutorial, and found something that totally confused me: Given the following example: public Bicycle(int startCadence, int startSpeed, int startGear) { gear = startGear; cadence = startCadence; speed = startSpeed; } Why is it, that the types of the variables (fields?) gear, cadence and speed do not need to be defined? I would have written it as follows: public Bicycle(int startCadence, int startSpeed, int startGear) { int gear = startGear; int cadence = startCadence; int speed = startSpeed; } What would be the actual differnce?

    Read the article

  • How to synchronize static method in java.

    - by Summer_More_More_Tea
    Hi there: I come up with this question when implementing singleton pattern in Java. Even though the example listed blow is not my real code, yet very similar to the original one. public class ConnectionFactory{ private static ConnectionFactory instance; public static synchronized ConnectionFactory getInstance(){ if( instance == null ){ instance = new ConnectionFactory(); } return instance; } private ConnectionFactory(){ // private constructor implementation } } Because I'm not quite sure about the behavior of a static synchronized method, I get some suggestion from google -- do not have (or as less as possible) multiple static synchronized methods in the same class. I guess when implementing static synchronized method, a lock belongs to Class object is used so that multiple static synchronized methods may degrade performance of the system. Am I right? or JVM use other mechanism to implement static synchronized method? What's the best practice if I have to implement multiple static synchronized methods in a class? Thank you all! Kind regards!

    Read the article

  • Java: refactoring static constants

    - by akf
    We are in the process of refactoring some code. There is a feature that we have developed in one project that we would like to now use in other projects. We are extracting the foundation of this feature and making it a full-fledged project which can then be imported by its current project and others. This effort has been relatively straight-forward but we have one headache. When the framework in question was originally developed, we chose to keep a variety of constant values defined as static fields in a single class. Over time this list of static members grew. The class is used in very many places in our code. In our current refactoring, we will be elevating some of the members of this class to our new framework, but leaving others in place. Our headache is in extracting the foundation members of this class to be used in our new project, and more specifically, how we should address those extracted members in our existing code. We know that we can have our existing Constants class subclass this new project's Constants class and it would inherit all of the parent's static members. This would allow us to effect the change without touching the code that uses these members to change the class name on the static reference. However, the tight coupling inherent in this choice doesn't feel right. before: public class ConstantsA { public static final String CONSTANT1 = "constant.1"; public static final String CONSTANT2 = "constant.2"; public static final String CONSTANT3 = "constant.3"; } after: public class ConstantsA extends ConstantsB { public static final String CONSTANT1 = "constant.1"; } public class ConstantsB { public static final String CONSTANT2 = "constant.2"; public static final String CONSTANT3 = "constant.3"; } In our existing code branch, all of the above would be accessible in this manner: ConstantsA.CONSTANT2 I would like to solicit arguments about whether this is 'acceptable' and/or what the best practices are.

    Read the article

  • Using an interface as a constructor parameter in Java?

    - by aperson
    How would I be able to accomplish the following: public class testClass implements Interface { public testClass(Interface[] args) { } } So that I could declare Interface testObject = new testClass(new class1(4), new class2(5)); Where class1 and class2 are also classes that implement Interface. Also, once I accomplish this, how would I be able to refer to each individual parameter taken in to be used in testClass? Thanks :)

    Read the article

  • How good idea is it to use code contracts in Visual Studio 2010 Professional (ie. no static checking

    - by Lasse V. Karlsen
    I create class libraries, some which are used by others around the world, and now that I'm starting to use Visual Studio 2010 I'm wondering how good idea it is for me to switch to using code contracts, instead of regular old-style if-statements. ie. instead of this: if (String.IsNullOrWhiteSpace(fileName)) throw new ArgumentNullException("fileName"); (yes, I know, if it is whitespace, it isn't strictly null) use this: Contract.Requires(!String.IsNullOrWhiteSpace(fileName)); The reason I'm asking is that I know that the static checker is not available to me, so I'm a bit nervous about some assumptions that I make, that the compiler cannot verify. This might lead to the class library not compiling for someone that downloads it, when they have the static checker. This, coupled with the fact that I cannot even reproduce the problem, would make it tiresome to fix, and I would gather that it doesn't speak volumes to the quality of my class library if it seemingly doesn't even compile out of the box. So I have a few questions: Is the static checker on by default if you have access to it? Or is there a setting I need to switch on in the class library (and since I don't have the static checker, I won't) Are my fears unwarranted? Is the above scenario a real problem? Any advice would be welcome.

    Read the article

  • What does static and IOException mean?

    - by Brian
    I just had a test on java and we had to give the definition of 1) Static: 2) IOExcepion: What I said for static was...a static method is used to define a method as a class method. And I got it wrong so I asked my teacher and he said he wants the actually definition of static not a static method, class or variable just static. Can someone tell me the definition of this and for IOException please Thanks.

    Read the article

  • Performance side effect with static internal Util classes?

    - by Fostah
    For a util class that contains a bunch of static functionality that's related to the same component, but has different purposes, I like to use static internal classes to organize the functionality, like so: class ComponentUtil { static class Layout { static int calculateX(/* ... */) { // ... } static int calculateY(/* ... */) { // ... } } static class Process { static int doThis(/* ... */) { // ... } static int doThat(/* ... */) { // ... } } } Is there any performance degradation using these internal classes vs. just having all the functionality in the Util class?

    Read the article

  • How do I access static variables in an enum class without a class instance?

    - by krick
    I have some code that processes fixed length data records. I've defined the record structures using java enums. I've boiled it down the the simplest example possible to illustrate the hoops that I currently have to jump through to get access to a static variable inside the enum. Is there a better way to get at this variable that I'm overlooking? If you compile and run the code, it just prints out "3". Note: the "code" tag doesn't seem to want to format this properly, but it should compile. class EnumTest { private interface RecordLayout { public int length(); } private enum RecordType1 implements RecordLayout { FIELD1 (2), FIELD2 (1), ; private int length; private RecordType1(int length) { this.length = length; } public int length() { return length; } public static int LEN = 3; } private static <E extends Enum<E> & RecordLayout> String parse(String data, Class<E> record) { // ugly hack to get at LEN... try { int len = record.getField("LEN").getInt(record); System.out.println(len); } catch (Exception e) { System.out.println(e); } String results = ""; for (E field: record.getEnumConstants()) { // do some stuff with the fields } return results; } public static void main(String args[]) { parse("ABC", RecordType1.class); } }

    Read the article

  • Copy Constructors and calling functions

    - by helixed
    Hello, I'm trying to call an accessor function in a copy constructor but it's not working. Here's an example of my problem: A.h class A { public: //Constructor A(int d); //Copy Constructor A(const A &rhs); //accessor for data int getData(); //mutator for data void setData(int d); private: int data; }; A.cpp #include "A.h" //Constructor A::A(int d) { this->setData(d); } //Copy Constructor A::A(const A &rhs) { this->setData(rhs.getData()); } //accessor for data int A::getData() { return data; } //mutator for data void A::setData(int d) { data = d; } When I try to compile this, I get the following error: error: passing 'const A' as 'this' argument of 'int A::getData()' discards qualifiers If I change rhs.getData() to rhs.data, then the constructor works fine. Am I not allowed to call functions in a copy constructor? Could somebody please tell me what I'm doing wrong? Thanks, helixed

    Read the article

  • Managing Static Library project as a module like Framework on iOS project in Xcode4.

    - by Eonil
    (Solution Note, I'll answer immediately) Many people including me trying to make a kind of Static Library framework for iOS to archive some kind of modularity. Framework is best way to do this, but it doesn't provided by Apple, and workarounds don't work well. https://github.com/kstenerud/iOS-Universal-Framework/tree/master/Fake%20Framework/Templates Fake framework cannot be referenced from linking tab in Build Phases. Real framework needs modification of system setting. And still not work smoothly on every parts. Problem is static library need header files, and it's impossible to reference header files on project at another location on different project without some script. And script breaks IDE's file management abstraction. How can I use static library project like a convenient module manner? (just dragging project into another project to complete embedding)

    Read the article

  • Is there a way to catch a MOUSE_UP Event over a static textfield in Flash?

    - by Jovica Aleksic
    When the user presses the mouse, and releases it over a static textfield with selectable text, no MOUSE_UP event is fired - not on the stage and also nowhere else. I experienced this when using a scrollbar class on a movieclip with a nested static textfield. When the user drags the scroll handle and releases the mouse over the textfield, the dragging/scrolling is stuck. To test this, create a new AS3 fla file, place a static textfield somewhere, and put in some text. Make sure the selectable property is checked in the properties panel. Add this script to the timeline: import flash.events.* function down(event:Event):void { trace('down'); } function up(event:Event):void { trace('up'); } stage.addEventListener(MouseEvent.MOUSE_DOWN, down) stage.addEventListener(MouseEvent.MOUSE_UP, up) Now test the movie and click the mouse. You will notice that trace('up') will not occur when you release the mouse over the textfield.

    Read the article

  • How to initialize a static const map in c++?

    - by Meloun
    Hi, I need just dictionary or asociative array string = int. There is type map C++ for this case. But I need make one map in my class make for all instances(- static) and this map cannot be changed(- const); I have found this way with boost library std::map<int, char> example = boost::assign::map_list_of(1, 'a') (2, 'b') (3, 'c'); Is there other solution without this lib? I have tried something like this, but there are always some issues with map initialization. class myClass{ private: static map<int,int> create_map() { map<int,int> m; m[1] = 2; m[3] = 4; m[5] = 6; return m; } static map<int,int> myMap = create_map(); } thanks

    Read the article

  • How can I change the value or a static char* from a function? C++

    - by flyout
    I am trying to change the value of a "static char *" I define at startup, I do it from inside a function, and when this function returns the var I am trying to re-set the value doesn't retain it. Example: static char *X = "test_1"; void testFunc() { char buf[256]; // fill buf with stuff... X = buf; } How can I achieve this without using static for buf? Should I use another datatype? if so, which one?

    Read the article

  • Where should common static resources (images, js, css, etc) go in DotNetNuke?

    - by Joosh21
    Is there a recommended location to store static resources (images, css, js, etc) in a DotNetNuke 5.x installation? There are /images and /js folders as well as a /Resources folder that contains resources. There appears to be some overlap as MicrosoftAjax.js is in multiple locations (but might be different versions?). I also could put resources in a /DesktopModule/ModuleX location. Does anyone know if there is a difference in using any of these folders? I kinda like the idea of all static resources being under a common folder (/Resources) so I could set caching rule headers, permissions, etc on them in one place. Has anyone used a separate image server to serve DotNetNuke static content? http://stackoverflow.com/questions/913208/pros-and-cons-of-a-separate-image-server-e-g-images-mydomain-com

    Read the article

  • Can I use a static var to "cache" the result? C++

    - by flyout
    I am using a function that returns a char*, and right now I am getting the compiler warning "returning address of local variable or temporary", so I guess I will have to use a static var for the return, my question is can I make something like if(var already set) return var else do function and return var? This is my function: char * GetUID() { TCHAR buf[20]; StringCchPrintf(buf, 20*sizeof(char), TEXT("%s"), someFunction()); return buf; } And this is what I want to do: char * GetUID() { static TCHAR buf[20]; if(strlen(buf)!=0) return buf; StringCchPrintf(buf, 20*sizeof(char), TEXT("%s"), someFunction()); return buf; } Is this a well use of static vars? And should I use ZeroMemory(&buf, 20*sizeof(char))? I removed it because if I use it above the if(strlen...) my TCHAR length is never 0, should I use it below?

    Read the article

  • C# Add class instance with internal timer to a static List, is it safe?

    - by CodeMongo
    My program has a static list of type classA. ClassA implements a threading timer that executes a task. The list may contain as many instances of classA as desired. Is this technique causing threading issues where the class instances can block each other? It that is the case how can I solve the that problem. ex: static List<MyClassType> list=null; void static Main() { list = new List<MyClassType>(); var a = new MyClassType(); var b = new MyClassType(); list.Add(a); list.Add(b); Console.ReadKey(); } a and b will execute theire internal task based on the timer.Is it s bsd technique? Why?

    Read the article

  • Unit testing of static library that involves NSDocumentDirectory and other iOS App specific calls.

    - by Shiun
    Hi, I'm attempting to run unit tests for a static library that attempts to create/write/read a file in the document directory. Since this is a static library and not an application for the iOS, attempts to reference the NSDocumentDirectory is returning me directory for the form "/Users//Library/Application Support/iPhone Simulator/Documents" This directory does not exist. When attempting to access a directory from an actual application, the NSDocumentDirectory returns something of the form: "/Users//Library/Application Support/iPhone Simulator/4.2/FEDBEF5F-1326-4383-A087-CDA1B865E61A/Documents" (Please note the simulator version as well as application ID as part of the path) How can I overcome this shortcoming in the unit test framework for static libraries that implement tests that require iOS app specific calls? Thanks in advance.

    Read the article

  • Header unset Server not working for static files

    - by Sam Lee
    I'm trying to unset the "Server" field in response headers. I do this using Header unset Server, and that works fine for requests handled by mod_perl. However, for requests to /static I use Apache to serve static files. For some reason, when these files are loaded directly in the browser, the Server field is not removed. How can I go about fixing this? Relevent parts of my httpd.conf: LoadModule headers_module modules/mod_headers.so Header unset Server <VirtualHost *:80> <Location /> SetHandler modperl PerlResponseHandler MyHandler </Location> Alias /static/ /home/site/static/ <Location /static> SetHandler None </Location> </VirtualHost>

    Read the article

< Previous Page | 29 30 31 32 33 34 35 36 37 38 39 40  | Next Page >