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Search found 50304 results on 2013 pages for 'class variables'.

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  • Has anyone used ever Mangoslick from themeforest?

    - by bonesnatch
    I was assigned to integrate MangoSlick theme to our current admin panel, Its a jQuery, Slick(?) and Responsive template. First, let me explain how the API goes In the documentation, it only says this is the only way data-[options]=[value] Example: If I wanna make a progress bar I can use this format <div class="progress"> <div class="bar" data-title="[title]" data-value="[value]" data-max="[max]" data-format="[format string]"></div> </div> so filling-in values <div class="progress"> <div class="bar" data-title="Space" data-value="1285" data-max="5120" data-format="0,0 MB"></div> </div> I will have this as output Now, the main question is when I use jQuery attr() to change the attribute values for data-title, data-max, data-value and data-format. Why is it not working? <script> var jq = $.noConflict(); jq(document).ready(function(){ jq('#bokz').attr("data-title", "No Space"); }); </script> Using the script above and inspect element in chrome the values are changed but not in the progressbar Some of you may have some ideas on this? Any help/suggestion would be very much appreciated.

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  • Best solution for __autoload

    - by tpk
    As our PHP5 OO application grew (in both size and traffic), we decided to revisit the __autoload() strategy. We always name the file by the class definition it contains, so class Customer would be contained within Customer.php. We used to list the directories in which a file can potentially exist, until the right .php file was found. This is quite inefficient, because you're potentially going through a number of directories which you don't need to, and doing so on every request (thus, making loads of stat() calls). Solutions that come to my mind... -use a naming convention that dictates the directory name (similar to PEAR). Disadvantages: doesn't scale too great, resulting in horrible class names. -come up with some kind of pre-built array of the locations (propel does this for its __autoload). Disadvantage: requires a rebuild before any deploy of new code. -build the array "on the fly" and cache it. This seems to be the best solution, as it allows for any class names and directory structure you want, and is fully flexible in that new files just get added to the list. The concerns are: where to store it and what about deleted/moved files. For storage we chose APC, as it doesn't have the disk I/O overhead. With regards to file deletes, it doesn't matter, as you probably don't wanna require them anywhere anyway. As to moves... that's unresolved (we ignore it as historically it didn't happen very often for us). Any other solutions?

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  • Design issue when having classes implement different interfaces to restrict client actions

    - by devoured elysium
    Let's say I'm defining a game class that implements two different views: interface IPlayerView { void play(); } interface IDealerView { void deal(); } The view that a game sees when playing the game, and a view that the dealer sees when dealing the game (this is, a player can't make dealer actions and a dealer can't make player actions). The game definition is as following: class Game : IPlayerView, IDealerView { void play() { ... } void deal() { ... } } Now assume I want to make it possible for the players to play the game, but not to deal it. My original idea was that instead of having public Game GetGame() { ... } I'd have something like public IPlayerView GetGame() { ... } But after some tests I realized that if I later try this code, it works: IDealerView dealerView = (IDealerView)GameClass.GetGame(); this works as lets the user act as the dealer. Am I worrying to much? How do you usually deal with this patterns? I could instead make two different classes, maybe a "main" class, the dealer class, that would act as factory of player classes. That way I could control exactly what I would like to pass on the the public. On the other hand, that turns everything a bit more complex than with this original design. Thanks

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  • Design patterns for Caching Images in a MVC?

    - by Onema
    Hi, I'm designing an image cache system that will be used in an MVC CMS. The main purpose of the image cacher is to modify images: scale, crop, etc and cache them in the client site. I have created an image cache Model and Mapper that interact with the Database, to keep track of the images and know what kind of actions have been applied to them (scale, crop, etc). In addition to the Model and Mapper I have created a ImageCacher Class that is used by the API to manage the Model and image creation based on arguments passed by the client site, this class creates the images and generates the links to the images for the View. A coworker argued that I need to include the functionality of this last Class inside the Model, as the bulk of the logic should go in the model. I respectfully disagree with him since I feel the model's responsibility is to deal with the information about the images cached at the database level, and the responsibility of the ImageCacher Class is to create the url/image that we will be caching (keeping the single responsibility principle). In addition to this I believe that a model should not have Presentation-related features, like creating or showing images. Does anyone have any insight on this? is there a particular design pattern that would make this division of tasks clear and and the image cacher reusable? Should I add all the logic in the Model? Thank you.

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  • random image and its url

    - by venom
    i want to create a random image and its url, i mean not the link of the image, but in addition to image's link, i want the specified URL, so that random image was displayed and when u click on it, u go to the specified URL here is my javascript: function random_imglink(){ var myimages=new Array() //specify random images below. You can have as many as you wish myimages[1]="/documents/templates/projedepo/banner/canon.jpg" myimages[2]="/documents/templates/projedepo/banner/indigovision.jpg" var ry=Math.floor(Math.random()*myimages.length) if (ry==0) ry=1 var randomImage = '<img src="'+myimages[ry]+'" height="420" width="964" />'; document.getElementById("image2").innerHTML = randomImage; } random_imglink() Here is my HTML: <div id="slider_container"> <div id="image2"> </div> <div id="thumb2"> <a href="#" rel="/documents/templates/projedepo/banner/canon.jpg" class="image2" ><img title="Canon" class="slider_thumb" src="/documents/templates/bilgiteknolojileri/images/t_flash/t1.png" border="0"/></a> <a href="#" rel="/documents/templates/projedepo/banner/indigovision.jpg" class="image2"><img title="IndogoVision" class="slider_thumb" src="/documents/templates/bilgiteknolojileri/images/t_flash/t2.png" border="0"/></a> </div></div>

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  • XmlSerializer construction with same named extra types

    - by NoizWaves
    Hey, I am hitting trouble constructing an XmlSerializer where the extra types contains types with the same Name (but unique Fullname). Below is an example that illustrated my scenario. Type definitions in external assembly I cannot manipulate: public static class Wheel { public enum Status { Stopped, Spinning } } public static class Engine { public enum Status { Idle, Full } } Class I have written and have control over: public class Car { public Wheel.Status WheelStatus; public Engine.Status EngineStatus; public static string Serialize(Car car) { var xs = new XmlSerializer(typeof(Car), new[] {typeof(Wheel.Status),typeof(Engine.Status)}); var output = new StringBuilder(); using (var sw = new StringWriter(output)) xs.Serialize(sw, car); return output.ToString(); } } The XmlSerializer constructor throws a System.InvalidOperationException with Message "There was an error reflecting type 'Engine.Status'" This exception has an InnerException of type System.InvalidOperationException and with Message "Types 'Wheel.Status' and 'Engine.Status' both use the XML type name, 'Status', from namespace ''. Use XML attributes to specify a unique XML name and/or namespace for the type." Given that I am unable to alter the enum types, how can I construct an XmlSerializer that will serialize Car successfully?

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  • C# generics with MVVM, pulling the T out of <T>

    - by bufferz
    My Model is a generic class that contains a (for example) Value property which can be int, float, string, bool, etc. So naturally this class is represented something like Model<T>. For the sake of collections Model<T> implements the interface IModel, although IModel is itself empty of any content. My ViewModel contains and instance of Model<T> and it is passed in through ViewModel's constructor. I still want to know what T is in ViewModel, so when I expose Model to the View I know the datatype of Model's buried Value property. The class for ViewModel ends up looking like the following: class ViewModel<T> { private Model<T> _model; public ViewModel(Model<T> model) { ....blah.... } public T ModelsValue {get; set; } } This works fine, but is limited. So now I need to expose a collection of IModels with varying Ts to my View, so I'm trying to set up an ObservableCollection of new ViewModel<T>s to a changing list of IModels. The problem is, I can't figure out how to get T from Model<T> from IModel to construct ViewModel<T>(Model<T>) at runtime. In the VS2010 debugger I can mouseover any IModel object and see its full Model<int> for example at runtime so I know the data is in there. Any ideas?

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  • Waiting until one event has happened before moving onto the next.

    - by jaasum
    I currently have a scrolling anchor animation that also adds an "active" class to the anchor clicked. I am trying to fit the below function into the works as well, so say someone clicks "anchor 1", "anchor 1" will get an active class and the window will scroll to that location. But, after that has happened say the user manually begins scrolling down the page, I want the active class to be removed. The problem I am running up against now is that the below function will happen when the scrolling animation from a clicked anchor is taking place. How can I disable this only when the window is being scrolled from a clicked anchor? $(window).scroll(function() { $('a[href^=#]').removeClass('active'); }); Here is the scrolling anchor script I am working with. /******* *** Anchor Slider by Cedric Dugas *** *** Http://www.position-absolute.com *** Never have an anchor jumping your content, slide it. Don't forget to put an id to your anchor ! You can use and modify this script for any project you want, but please leave this comment as credit. *****/ jQuery.fn.anchorAnimate = function(settings) { settings = jQuery.extend({ speed : 500 }, settings); return this.each(function(){ var caller = this $(caller).click(function (event) { event.preventDefault() var locationHref = window.location.href var elementClick = $(caller).attr("href") var destination = $(elementClick).offset().top; $("html:not(:animated),body:not(:animated)").animate({ scrollTop: destination}, settings.speed, 'easeOutCubic', function() { window.location.hash = elementClick }); return false; }) }) } And lastly, my jQuery // Scrolling Anchors $('[href^=#]').anchorAnimate(); // Active Class For Clicked Anchors var anchorscroll = $('a[href^=#]') anchorscroll.click(function(){ var anchorlocation = $(this).attr("href"); anchorscroll.removeClass('active'); $(this).addClass('active'); $('a[href='+anchorlocation+']').addClass('active'); });

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  • Database/Object Mapping

    - by Eric
    Hello everyone, This is a beginner question, but it's been frustrating me... I am using C#, by the way. I'd like to make a few classes, each with their own properties and methods. I would also like to have a database to store certain instances of these classes in case I would ever need to look at them again. So, for example... class Polygon { String name; Double perimiter; int numSides; public Double GetArea() { // ... } } class Circle { String name; Double radius; public void PrintName() { // ... } } Say I've got these classes. I also want a database that has the TABLES "Polygon" and "Circle" with the COLUMNS "name" "perimeter" "radius" etc. And I want an easy way to save a class instance into the database, or pull a class instance out of the database. I have previously been using MS Access for my database stuff, which I don't mind using, but I would prefer if nothing other than .NET need to be installed. I've been researching online a bit, but I wanted to get some opinions on here. I have looked at Linq-to-Sql, but it seems you need Sql-Server. Is this true? If so, I'd really rather not use it because I don't want to have to have it installed everywhere. Anway, I'm just fishing for some ideas/insights/suggestions/etc. so please help me out if you can. Thanks.

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  • [jQuery UI - Accordion] Styling active header?

    - by RC
    Hi, Simple issue: I am using Accordion without any UI themes (just barebones, using my own CSS). So far, so good, except that I cannot figure out how to set an "active" style for the currently selected header. The jQuery code: $("#menu").accordion({ event:"mouseover",header:"a.top" }); The HTML code: <a href="#" class="top">XXX1</a> <div class="sub"> <a href="#">Subheading 1</a> <a href="#">Subheading 2</a> <a href="#">Subheading 3</a> </div> <a href="#" class="top">XXX2</a> <div class="sub"> <a href="#">Subheading 1</a> <a href="#">Subheading 2</a> <a href="#">Subheading 3</a> </div> This works great, except that I cannot find a way to define the styles for the active header without using ThemeRoller. Manually setting the following styles in my CSS has no effect: .ui-state-active .ui-widget-content .ui-state-active .ui-state-active a .ui-state-active a:link .ui-state-active a:visited Assistance, please?

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  • Modulo jquery question

    - by chchrist
    Hi all, Dont ask why but I need to add class zebra to the lis with the content next to them. I do a $("li").each(function(index){ if(index%??? == 0) { } }); <ul> <li></li> <li></li> <li></li> //add here class zebra <li></li> <li></li> <li></li> <li></li> //add here class zebra <li></li> <li></li> <li></li> <li></li> //add here class zebra <li></li> </ul>

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  • Problem in mutiple :dependent=> :destroy when multiple polymorphic is true

    - by piemesons
    I have four models question, answer, comment and vote.Consider it same as stackoverflow. Question has_many comments Answers has_many comments Questions has_many votes answers has_many votes comments has_many votes Here are the models (only relevant things) class Comment < ActiveRecord::Base belongs_to :commentable, :polymorphic => true has_many :votes, :as => :votable, :dependent => :destroy end class Question < ActiveRecord::Base has_many :comments, :as => :commentable, :dependent => :destroy has_many :answers, :dependent => :destroy has_many :votes, :as => :votable, :dependent => :destroy end class Vote < ActiveRecord::Base belongs_to :votable, :polymorphic => true end class Answer < ActiveRecord::Base belongs_to :question, :counter_cache => true has_many :comments, :as => :commentable , :dependent => :destroy end Now the problem is whenever i am trying to delete any question/answer/comment its giving me an error NoMethodError in QuestionsController#destroy undefined method `each' for 0:Fixnum if i remove this line from any of the model (question/answer/comment) has_many :votes, :as => :votable, :dependent => :destroy then it works perfectly. It seems there is a problem while deleting the records active record is not able to find out the proper path because of multiple joins within the tables.

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  • DCI: How to implement Context with Dependency Injection?

    - by ciscoheat
    Most examples of a DCI Context are implemented as a Command pattern. When using Dependency Injection though, it's useful to have the dependencies injected in the constructor and send the parameters into the executing method. Compare the Command pattern class: public class SomeContext { private readonly SomeRole _someRole; private readonly IRepository<User> _userRepository; // Everything goes into the constructor for a true encapsuled command. public SomeContext(SomeRole someRole, IRepository<User> userRepository) { _someRole = someRole; _userRepository = userRepository; } public void Execute() { _someRole.DoStuff(_userRepository); } } With the Dependency injected class: public class SomeContext { private readonly IRepository<User> _userRepository; // Only what can be injected using the DI provider. public SomeContext(IRepository<User> userRepository) { _userRepository = userRepository; } // Parameters from the executing method public void Execute(SomeRole someRole) { someRole.DoStuff(_userRepository); } } The last one seems a bit nicer, but I've never seen it implemented like this so I'm curious if there are any things to consider.

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  • Wordpress is_front_page if statment

    - by Anders Kitson
    I have the following code below. I am trying to get rid of the box articles div when I am on the home page the code works when the html is outside of the else portion of the IF statement, as soon as I put it inside the page goes blank, I can't seem to figure out where I have broken the code. Any help would be great. <?php if(is_front_page()) { if(function_exists('wp_content_slider')) { wp_content_slider(); } } else{ ?> <div class="box articles"> <div class="block" id="articles"> <h2><?php the_title(); ?></h2> <div class="article"> <div class="entry"> <?php the_content(); ?> </div> <?php edit_post_link('Modifca Contenuto.', '<p>', '</p>'); ?> </div> </div> </div> <?php endwhile; endif; ?> <? } ?>

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  • How is covariance cooler than polymorphism...and not redundant?

    - by P.Brian.Mackey
    .NET 4 introduces covariance. I guess it is useful. After all, MS went through all the trouble of adding it to the C# language. But, why is Covariance more useful than good old polymorphism? I wrote this example to understand why I should implement Covariance, but I still don't get it. Please enlighten me. using System; using System.Collections.Generic; using System.Linq; using System.Text; namespace Sample { class Demo { public delegate void ContraAction<in T>(T a); public interface IContainer<out T> { T GetItem(); void Do(ContraAction<T> action); } public class Container<T> : IContainer<T> { private T item; public Container(T item) { this.item = item; } public T GetItem() { return item; } public void Do(ContraAction<T> action) { action(item); } } public class Shape { public void Draw() { Console.WriteLine("Shape Drawn"); } } public class Circle:Shape { public void DrawCircle() { Console.WriteLine("Circle Drawn"); } } public static void Main() { Circle circle = new Circle(); IContainer<Shape> container = new Container<Circle>(circle); container.Do(s => s.Draw());//calls shape //Old school polymorphism...how is this not the same thing? Shape shape = new Circle(); shape.Draw(); } } }

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  • Nested bind expressions

    - by user328543
    This is a followup question to my previous question. #include <functional> int foo(void) {return 2;} class bar { public: int operator() (void) {return 3;}; int something(int a) {return a;}; }; template <class C> auto func(C&& c) -> decltype(c()) { return c(); } template <class C> int doit(C&& c) { return c();} template <class C> void func_wrapper(C&& c) { func( std::bind(doit<C>, std::forward<C>(c)) ); } int main(int argc, char* argv[]) { // call with a function pointer func(foo); func_wrapper(foo); // error // call with a member function bar b; func(b); func_wrapper(b); // call with a bind expression func(std::bind(&bar::something, b, 42)); func_wrapper(std::bind(&bar::something, b, 42)); // error // call with a lambda expression func( [](void)->int {return 42;} ); func_wrapper( [](void)->int {return 42;} ); return 0; } I'm getting a compile errors deep in the C++ headers: functional:1137: error: invalid initialization of reference of type ‘int (&)()’ from expression of type ‘int (*)()’ functional:1137: error: conversion from ‘int’ to non-scalar type ‘std::_Bind(bar, int)’ requested func_wrapper(foo) is supposed to execute func(doit(foo)). In the real code it packages the function for a thread to execute. func would the function executed by the other thread, doit sits in between to check for unhandled exceptions and to clean up. But the additional bind in func_wrapper messes things up...

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  • How to override part of an overload function in JavaScript

    - by Guan Yuxin
    I create a class with a function like this var Obj=function(){this.children=[];this.parent=null;}//a base class Obj.prototype.index=function(child){ // the index of current obj if(arguments.length==0){ return this.parent?this.parent.index(this):0; } // the index of a child matchs specific obj [to be override] return -1; } basically it is just an overload function composed of index() and index(child). Then I create a sub class,SubObj or whatever, inherits from Obj SubObj.prototype.prototype=Obj; Now, it's time to override the index(child) function,however, index() is also in the function an I don't want to overwrite it too. One solution is to write like this var Obj=function(){this.children=[];this.parent=null;}//a base class Obj.prototype.index=function(child){ // the index of current obj if(arguments.length==0){ return this.parent?this.parent.index(this):0; } // the index of a child matchs specific obj [to be override] return this._index(this); } Obj.prototype._index=function(this){ return -1; } SubObj.prototype._index=function(this){/* overwriteing */} But this will easily mislead other coders as _index(child) should be both private(should not be used except index() function) and public(is an overload function of index(),which is public) you guys have better idea?

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  • Cakephp 1.3, Weird behavior on firefox when using $this->Html->link ...

    - by ion
    Greetings, I am getting a very weird and unpredictable result in firefox when using the following syntax: $this->Html->link($this->Html->div('p-cpt',$project['Project']['name']) . $this->Html->div('p-img',$this->Html->image('/img/projects/'.$project['Project']['slug'].'/project.thumb.jpg', array('alt'=>$project['Project']['name'],'width'=>100,'height'=>380))),array('controller' => 'projects', 'action' => 'view', $project['Project']['slug']),array('title' => $project['Project']['name'], 'escape' => false),false); OK I know it is big but bear with me. The point is to get the following output: <a href="x" title="x"> <div class="p-ctp">Name</div> <div class="p-img"><img src="z width="y" height="a" alt="d" /></div> </a> I'm not sure if this validates correctly both on cakephp and html but it works everywhere else apart from firefox. You can actually see the result here: http://www.gnomonconstructions.com/projects/browser To reproduce the result use the form with different categories and press search. At some point it will happen!! Although most of the time it renders the way it should, sometimes it produces an invalid output like that: <a href="x" title="x"></a> <div class="p-cpt"> <a href="x" title="x">name</a> </div> <div class="p-img"> <a href="x" title="x"><img src="x" width="x" height="x" alt="x" /></a> </div> Looks like it repeats the link inside each element. To be honest the only reason I used this syntax was because cakephp encourages it. Any help will be much appreciated :)

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  • jQuery Fancy - popup window doesn't fully expand

    - by fmz
    I am using jQuery Fancybox to display a number of Flash videos on a site and I am having trouble with the window not opening fully on the first click in Firefox. It works fine in other browsers. Here is the jQuery: <script type="text/javascript"> $(document).ready(function() { $("a.videoLink").fancybox({ 'titleShow' : false, 'autoscale' : true, 'width' : '820', 'height' : '620', 'transitionIn' : 'elastic', 'transitionOut' : 'elastic' }); }); </script> Here is the html: <tr> <td class="title"><a class="videoLink" href="#video-content30">CPR Lesson 1 Movie</a></td> <td class="time">38:39</td> <td class="video" style="display:none"> <div id="video-content30"> <script type='text/javascript'> var flashvars = { file: 'http://www.stockmarketcpr.com/smsys/link/CPR-Lesson-1-Movie.flv', id: '30' }; var params = { wmode: 'opaque', bgcolor: '#CCCCCC', allowfullscreen: 'true', allowscriptaccess: 'always' }; swfobject.embedSWF('http://www.stockmarketcpr.com/_flash/player.swf', 'player30','800','600', '9.0.0','expressInstall.swf', flashvars, params); </script> <div id="player30"></div> </div> </td> </tr> I end up getting a quarter inch high, full-width window on the first click. The second click plays fine. I would appreciate any assistance. Thank you!

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  • How to pass a parameter in a Javascript confirm function?

    - by Miles M.
    I have something like that in my code: <?php foreach($clients as $client): ?> <tr class="tableContent"> <td onclick="location.href='<?php echo site_url('clients/edit/'.$client->id ) ?>'"><?php echo $client->id ?></td> <td><a class='Right btn btn-danger' onClick="ConfirmMessage('client', <?php $client->id ?>,'clients')"> <i class="icon-remove-sign icon-white"></i> </a></td> </tr> <?php endforeach ?> that's actually the view. So when the user click on the delete button (thr one with the btn-danger class) I'd like him to confirm his choice with a javascript confirmation box message. You can find that script in the header <script> function ConfirmMessage(type, id, types) { if (confirm("Are you sure you want to delete this ",type," ?")) { // Clic sur OK document.location.href='<?php echo site_url(); ?>',types,'/delete/',id; } } </script> So here is my question: I would like the $type to be replaced by a paramenter (like client, article, post .. ) that I'll pass to the function. And i would like to get the $client-id parameter as well. I'm bad in javascript and as you already have guess, It is obviously not working at all.

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  • object references an unsaved transient instance

    - by developer
    Hi, I have 2 tables, user and userprofile, both with almost identical fields. user table references userprofile table by primary key ID. My requirement is that on click of a button I need to dump user table record to userprofile table. Now for a particular user table, if there is a corresponding userprofile entry, I am successfully able to dump the data, but if there is no record in userprofile table then I need to create a new record by dumping all the data. My problem is that I am able to update the data when the record is present in userprofile table, but in the case wherein I have to create a new record I get the below error "object references an unsaved transient instance - save the transient instance before flushing". `<class name="User"> <id name="ID" type="Int32"> <generator class="native" /> </id> <many-to-one name="Pid" class="UserProfile" /> </class>` UserProfile is another table and Pid above references the Primary key ID of UserProfile table.

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  • Creating an adjacency List for DFS

    - by user200081
    I'm having trouble creating a Depth First Search for my program. So far I have a class of edges and a class of regions. I want to store all the connected edges inside one node of my region. I can tell if something is connected by the getKey() function I have already implemented. If two edges have the same key, then they are connected. For the next region, I want to store another set of connected edges inside that region, etc etc. However, I am not fully understanding DFS and I'm having some trouble implementing it. I'm not sure when/where to call DFS again. Any help would be appreciated! class edge { private: int source, destination, length; int key; edge *next; public: getKey(){ return key; } } class region { edge *data; edge *next; region() { data = new edge(); next = NULL; } }; void runDFS(int i, edge **edge, int a) { region *head = new region(); aa[i]->visited == true;//mark the first vertex as true for(int v = 0; v < a; v++) { if(tem->edge[i].getKey() == tem->edge[v].getKey()) //if the edges of the vertex have the same root { if(head->data == NULL) { head->data = aa[i]; head->data->next == NULL; } //create an edge if(head->data) { head->data->next = aa[i]; head->data->next->next == NULL; }//if there is already a node connected to ti } if(aa[v]->visited == false) runDFS(v, edge, a); //call the DFS again } //for loop }

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  • Java Inheritance doubt in parameterised collection

    - by Gala101
    It's obvious that a parent class's object can hold a reference to a child, but does this not hold true in case of parameterised collection ?? eg: Car class is parent of Sedan So public void doSomething(Car c){ ... } public void caller(){ Sedan s = new Sedan(); doSomething(s); } is obviously valid But public void doSomething(Collection<Car> c){ ... } public void caller(){ Collection<Sedan> s = new ArrayList<Sedan>(); doSomething(s); } Fails to compile Can someone please point out why? and also, how to implement such a scenario where a function needs to iterate through a Collection of parent objects, modifying only the fields present in parent class, using parent class methods, but the calling methods (say 3 different methods) pass the collection of three different subtypes.. Ofcourse it compiles fine if I do as below: public void doSomething(Collection<Car> c){ ... } public void caller(){ Collection s = new ArrayList<Sedan>(); doSomething(s); }

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  • 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.

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  • How does a java compiler resolve a non-imported name

    - by gexicide
    Consider I use a type X in my java compilation unit from package foo.bar and X is not defined in the compilation unit itself nor is it directly imported. How does a java compiler resolve X now efficiently? There are a few possibilities where X could reside: X might be imported via a star import a.b.* X might reside in the same package as the compilation unit X might be a language type, i.e. reside in java.lang The problem I see is especially (2.). Since X might be a package-private type, it is not even required that X resides in a compilation unit that is named X.java. Thus, the compiler must look into all entries of the class path and search for any classes in a package foo.bar, it then must read every class that is in package foo.bar to check whether X is included. That sounds very expensive. Especially when I compile only a single file, the compiler has to read dozens of class files only to find a type X. If I use a lot of star imports, this procedure has to be repeated for a lot of types (although class files won't be read twice, of course). So is it advisable to import also types from the same package to speed up the compilation process? Or is there a faster method for resolving an unimported type X which I was not able to find?

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