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  • How to be a better software designer

    - by Bmw
    I feel as if I am a hack programmer. I do things over and over again until they finally work. I copy/paste code. I don't think about why something makes sense, if it works I go with it. I have my undergraduate in computer science, and I've done this the entire time. Somehow I made it through the degree by doing this and now I'm in my second year of programming professionally and I am still able to do this and get away with it. Here's the thing, I don't want to be this way anymore. I am not proud of the work I do, I feel like I'm just a copy/paste programmer. How do I become better? I want to be able to design something on my own without copying code. Have you ever been in this situation, if so how did you move beyond it to become a better programmer? To add some background about myself, I started as an asp.net c# programmer, now I'm doing vbscript (which actually makes my tendency to copy/paste/hack a lot worse I must say!) with classic asp…

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  • JMS message. Model to include data or pointers to data?

    - by John
    I am trying to resolve a design difference of opinion where neither of us has experience with JMS. We want to use JMS to communicate between a j2ee application and the stand-alone application when a new event occurs. We would be using a single point-to-point queue. Both sides are Java-based. The question is whether to send the event data itself in the JMS message body or to send a pointer to the data so that the stand-alone program can retrieve it. Details below. I have a j2ee application that supports data entry of new and updated persons and related events. The person records and associated events are written to an Oracle database. There are also stand-alone, separate programs that contribute new person and event records to the database. When a new event occurs through any of 5-10 different application functions, I need to notify remote systems through an outbound interface using an industry-specific standard messaging protocol. The outbound interface has been designed as a stand-alone application to support scalability through asynchronous operation and by moving it to a separate server. The j2ee application currently has most of the data in memory at the time the event is entered. The data would consist of approximately 6 different objects; a person object and some with multiple instances for an average size in the range of 3000 to 20,000 bytes. Some special cases could be many times this amount. From a performance and reliability perspective, should I model the JMS message to pass all the data needed to create the interface message, or model the JMS message to contain record keys for the data and have the stand-alone Java application retrieve the data to create the interface message?

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  • is there a simple timed lock algorithm avoiding deadlock on multiple mutexes?

    - by Vicente Botet Escriba
    C++0x thread library or Boost.thread define a non-member variadic template function that locks all mutex at once that helps to avoid deadlock. template <class L1, class L2, class... L3> void lock(L1&, L2&, L3&...); The same can be applied to a non-member variadic template function try_lock_until, which locks all the mutex until a given time is reached that helps to avoid deadlock like lock(...). template <class Clock, class Duration, class L1, class L2, class... L3> void try_lock_until( const chrono::time_point<Clock,Duration>& abs_time, L1&, L2&, L3&...); I have an implementation that follows the same design as the Boost function boost::lock(...). But this is quite complex. As I can be missing something evident I wanted to know if: is there a simple timed lock algorithm avoiding deadlock on multiple mutexes? If no simple implementation exists, can this justify a proposal to Boost? P.S. Please avoid posting complex solutions.

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  • "Find all tiles connected to this one" project

    - by Omega
    Remember MS Paint? The bucket tool? If you used it and clicked on a pixel, all pixels connected to this pixel that are the same are affected. The theory is, I suppose, to check if there is any pixel adjacent to the selected one. If such pixel is the same type as the selected one, check for more adjacent pixels in this one, and so on. I want to implement something similar in VB.NET. Basically I have a 2D array map which represents the map. Let's assume there are only two types of tile: 0 and 1. Now, I got pretty much everything ready: I got my 2d map and I can tell which tile is clicked and tell what array indexes are the ones that represent such tile. Now for the "painting" process. Whenever I think about it, I can't figure a convenient way to execute such iteration. Can someone help me choosing a correct design/way/tip to achieve this?

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  • Calling member functions dynamically

    - by user652511
    I'm pretty sure it's possible to call a class and its member function dynamically in Delphi, but I can't quite seem to make it work. What am I missing? // Here's a list of classes (some code removed for clarity) moClassList : TList; moClassList.Add( TClassA ); moClassList.Add( TClassB ); // Here is where I want to call an object's member function if the // object's class is in the list: for i := 0 to moClassList.Count - 1 do if oObject is TClass(moClassList[i]) then with oObject as TClass(moClassList[i]) do Foo(); I get an undeclared identifier for Foo() at compile. Clarification/Additional Information: What I'm trying to accomplish is to create a Change Notification system between business classes. Class A registers to be notified of changes in Class B, and the system stores a mapping of Class A - Class B. Then, when a Class B object changes, the system will call a A.Foo() to process the change. I'd like the notification system to not require any hard-coded classes if possible. There will always be a Foo() for any class that registers for notification. Maybe this can't be done or there's a completely different and better approach to my problem. By the way, this is not exactly an "Observer" design pattern because it's not dealing with objects in memory. Managing changes between related persistent data seems like a standard problem to be solved, but I've not found very much discussion about it. Again, any assistance would be greatly appreciated. Jeff

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  • How important is the website logo on a page?

    - by meo
    I have stopped to insert "img" tags for the logo of the page. Because its not an image that is part of the content, its a design element but its still a information I want to have control over. So I just write the title in a "a" element as display: block, overflow: hidden and I push the text out with some padding. I think thats a good solution for SEO because you are keeping control of how important the logo should be on a page. But now my dilemma is starting. How important is the logo of a page? "A list apart" puts the logo in a h1 element. But is the logo really that important? On article pages you have two H1 elements (the logo and the title of the article) Most of the sites just use a img balbal /a, but I don't like this solution. Because I just want to use img for images that are part of the content... Its kinda philosophical question, I hope you can give me some input or some articles to read about that...

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  • Can one thread open a socket and other thread close it?

    - by Pkp
    I have some kernel threads in Linux kernel, inside my KLM. I have a server thread, that listens to the channel, Once it sees there is an incoming connection, it creates an accept socket, accepts the connection and spawns a child thread. It also passes the accepted socket to the child kernel thread as the (void *) argument. The code is working fine. I had a design question. Suppose now the threads have to be terminated, main and the child threads, what would be the best way to close the accept socket. I can see two ways, 1] The main thread waits for all the child threads to exit, each of the child threads close the accept sockets while exiting, the last child thread passes a signal to the main thread for it to exit . Here even though the main thread was the one that created the accept socket, the child threads close that socket, and they do this before the main thread exits. So is this acceptable? Any problems you guys forsee here? 2] Second is the main thread closes all the accept sockets it created before it exits. But there may be a possibility(corner case) that the main thread gets an exception and will have to close, so if it closes the accept sockets before exiting, the child threads using that socket will be in danger. Hence i am using the first case i mentioned.Let me know what you guys think?

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  • Handling text menu in Python

    - by PulpFiction
    Hi all. I am trying to create a text based menu in Python. Here is the code: #!/usr/bin/env python def testcaseOutput(): print '1. Add. 2. Subtract. 3. Divide. 4. Multiply' try: answer = int(raw_input('Enter a value (1 - 4) >. ')) except ValueError: print 'Invalid input. Enter a value between 1 -4 .' testcaseOutput() if answer in range(1, 5): return answer else: print 'Invalid input. Enter a value between 1 - 4.' testcaseOutput() My question: When the user enters an invalid input, i.e. not a number, I want this function to get called again. So I used the recursive approach which I think is bad design. I use that approach again in the if answer in range(1, 5). Is there any other way to handle this? I need the prompt called again when there is an invalid input. Also, is there any way I can club the two constraints: check whether input is a number and check whether the number is in the range(1,5) together? As you can see, I am checking that individually.

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  • Execute client & server side code with one click?

    - by Abu Hamzah
    i am not sure if my design have flaw but would like to know what others have to say, i am in a situation where i am trying to acheive two things in one click. using : asp.net web form i have a web form with few textbox and a gridview control and a button. if i click on the button i am executing two things 1) asynchronously get data from server to client (working great) and able to display the data in the textboxes. 2) same click i want to bind the gridview. <asp:Content ID="Content2" ContentPlaceHolderID="cphMaster" runat="server"> <asp:Label runat="server" ID='Label1' >Id:</asp:Label> <asp:TextBox ID="txtId" runat='server'></asp:TextBox> <asp:Button ID="btnSubmit" OnClientClick="LoadDataById();" runat="server" Text="Submit" onclick="btnSubmit_Click" /> <br /> <br /> <asp:TextBox ID="txtName" runat='server'></asp:TextBox> <br /> <asp:TextBox ID="txtPurpose" runat='server'></asp:TextBox> <br /> <br /> <asp:GridView ID="GridView1" runat="server"> </asp:GridView> </asp:Content> server side protected void btnSubmit_Click(object sender, EventArgs e) { GridView1.DataSource = laodData(int.Parse(txtId.Text)); GridView1.DataBind(); } Jquery: function LoadVisitBasicByVisitId() { ContactServiceProxy.invoke({ serviceMethod: "GetDataById", data: { request: request }, callback: function(response) { processCompletedContactStore(response); }, error: function(xhr, errorMsg, thrown) { postErrorAndUnBlockUI(xhr, errorMsg, thrown); } }); return false; } recap: 1) jquery script execute asynchronously to get data from server to client and display in the textboxes 2) server side code to bind the gridview.

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  • Localization of DisplayNameAttribute

    - by PowerKiKi
    Hi, I am looking for a way to localize properties names displayed in a PropertyGrid. The property's name may be "overriden" using the DisplayNameAttribute attribute. Unfortunately attributes can not have non constant expressions. So I can not use strongly typed resources such as: class Foo { [DisplayAttribute(Resources.MyPropertyNameLocalized)] // do not compile string MyProperty {get; set;} } I had a look around and found some suggestion to inherit from DisplayNameAttribute to be able to use resource. I would end up up with code like: class Foo { [MyLocalizedDisplayAttribute("MyPropertyNameLocalized")] // not strongly typed string MyProperty {get; set;} } However I lose strongly typed resource benefits which is definitely not a good thing. Then I came across DisplayNameResourceAttribute which may be what I'm looking for. But it's supposed to be in Microsoft.VisualStudio.Modeling.Design namespace and I can't find what reference I am supposed to add for this namespace. Anybody know if there's a easier way to achieve DisplayName localization in a good way ? or if there is as way to use what Microsoft seems to be using for Visual Studio ?

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  • Are reads and (transactional) writes faster for entities of the same group than otherwise?

    - by indiehacker
    What advantage is there to designing child-parent relationships, which allow us to do writes in transactions, when there is never a real concern for consistency and contention and those sort of more complex issues? Does it make writes and reads faster? Consider my situation where there are many .png images that are referenced to one mosaic layer, and these .png images are written just once by a single user. The user can design many mosaic layers and her mosaic layers and referenced image entities are never changed/updated, they are just deleted some time in the future. Other users can come to the web project site and interactively view the mosaic layer as different layouts/configurations of the images as they play (query) with different criteria. So reads should be very fast. So there is no real worry of contention, or users conflicting with one another with writing new image entities. And because of that I am assuming there is no "requirement" for the .png image entities to be grouped by their same mosaic layer in child-parent relationship. However, perhaps, since the documentation says they are stored close to one another, if the many image entities were grouped as children to a single mosaic layer parent than this has the advantage that the writing (in transaction) and reading will happen much faster?

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  • git + partly shared files between branches/repositories. Is it possible?

    - by Maxym
    One team in company I work for has the following problem. They develop an application, which will have different builds (e.g. different design depending on customer). so they have some code shared between builds, and some specific to build. E.g. first build has (example is meaningless about files, it is just to understand the problem; I don't know exactly which code differs) /src/class1.java /src/class2.java /res/image1.png /res/image2.png second project contains /src/class1.java /src/class3.java /res/image1.png /res/image3.png as you see, both have class1.java and image1.png. Evething else is different. The project is much more complex of course, so to contain everything in one project is not comfortable... But also to make different branches and commit the same code to all of them is not comfortable... probably I picked wrong direction thinking about this problem, but I just took a look at git (we use svn), and it allows separated repositories. The question is: is it possible to make different branches in git, but tell it that "these files should be shared between them" and other files should be only in those branches. Then when developer commits class1.java git synchronizes it in all branches/repositorias etc. Maybe there is another solution which can be easy taken?

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  • RESTful API: How to model JSON representation?

    - by Jan P.
    I am designing a RESTful API for a booking application. You can request a list of accommodations. And that's where I don't really know how to design the JSON represenation. This is my XML representation: <?xml version="1.0" encoding="utf-8"?> <accommodations> <accommodation> <name>...</name> <category>couch</category> </accommodation> <accommodation> <name>...</name> <category>room</category> </accommodation> <accommodations> My first try to convert this to JSON resulted in this output (1): { "0": { "name": "...", "category": "couch" }, "1": { "name": "...", "category": "room" } } But as I looked how others APIs did it, I found something looking more like this (2): [ { "name": "...", "category": "couch" }, { "name": "...", "category": "room" } ] I know version 1 is an object, and version 2 an array. But which one is better in this case?

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  • C# property exactly the same, defined in two places

    - by Sarah Vessels
    I have the following classes: Defect - represents a type of data that can be found in a database FilterQuery - provides a way of querying the database by setting simple Boolean filters Both Defect and FilterQuery implement the same interface: IDefectProperties. This interface specifies particular fields that are in the database. Different classes have methods that return lists of Defect instances. With FilterQuery, you specify some filters for the particular properties implemented as part of IDefectProperties, and then you run the query and get back a list of Defect instances. My problem is that I end up implementing some properties exactly the same in FilterQuery and Defect. The two are inherently different classes, they just share some of the same properties. For example: public DateTime SubmitDateAsDate { get { return DateTime.Parse(SubmitDate); } set { SubmitDate = value.ToString(); } } This is a property required by IDefectProperties that depends on a different property, SubmitDate, which returns a string instead of a DateTime. Now SubmitDate is implemented differently in Defect and FilterQuery, but SubmitDateAsDate is exactly the same. Is there a way that I can define SubmitDateAsDate in only place, but both Defect and FilterQuery provide it as a property? FilterQuery and Defect already inherit from two different classes, and it wouldn't make sense for them to share an ancestor anyway, I think. I am open to suggestions as to my design here as well.

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  • has_many :through default values

    - by David Lyod
    I have a need to design a system to track users memberships to groups with varying roles (currently three). class Group < ActiveRecord::Base has_many :memberships has_many :users, :through => :memberships end class Role < ActiveRecord::Base has_many :memberships has_many :users, :through => :memberships end class Membership < ActiveRecord::Base belongs_to :user belongs_to :role belongs_to :group end class User < ActiveRecord::Base has_many :memberships has_many :groups, :through => :memberships end Ideally what I want is to simply set @group.users << @user and have the membership have the correct role. I can use :conditions to select data that has been manually inserted as such : :conditions => ["memberships.grouprole_id= ? ", Grouprole.find_by_name('user')] But when creating the membership to the group the grouprole_id is not being set. Is there a way to do this as at present I have a somewhat repetitive piece of code for each user role in my Group model.

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  • Comparing lists of field-hashes with equivalent AR-objects.

    - by Tim Snowhite
    I have a list of hashes, as such: incoming_links = [ {:title => 'blah1', :url => "http://blah.com/post/1"}, {:title => 'blah2', :url => "http://blah.com/post/2"}, {:title => 'blah3', :url => "http://blah.com/post/3"}] And an ActiveRecord model which has fields in the database with some matching rows, say: Link.all => [<Link#2 @title='blah2' @url='...post/2'>, <Link#3 @title='blah3' @url='...post/3'>, <Link#4 @title='blah4' @url='...post/4'>] I'd like to do set operations on Link.all with incoming_links so that I can figure out that <Link#4 ...> is not in the set of incoming_links, and {:title => 'blah1', :url =>'http://blah.com/post/1'} is not in the Link.all set, like so: #pseudocode #incoming_links = as above links = Link.all expired_links = links - incoming_links missing_links = incoming_links - links expired_links.destroy missing_links.each{|link| Link.create(link)} One route I've tried: I'd rather not rewrite Array#- and such, and I'm okay with converting incoming_links to a set of unsaved Link objects; so I've tried overwriting hash eql? and so on in Link so that it ignored the id equality that AR::Base provides by default. But this is the only place this sort of equality should be considered in the application - in other places the Link#id default identity is required. Is there some way I could subclass Link and apply the hash, eql?, etc overwriting there? The other route I've tried is to pull out the attributes hash for each Link and doing a .slice('id',...etc) to prune the hashes down. But this requires writing seperate methods for keeping track of the Link objects while doing set operations on the hashes, or writing seperate Collection classes to wrap the incoming_links hash-list and Link-list which seems a bit overkill. What is the best way to design this interaction? Extra credit for cleanliness.

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  • jQuery .ready() automatically assigning variables for each element with ID in DOM

    - by Greg
    I have noticed some unexpected behaviour when using the jQuery .ready() function, whereby afterwards you can reference an element in the DOM simply by using its ID without prior declaration or assignment: <html> <script src="jquery.js"></script> <script> $(document).ready(function() { myowndiv.innerHTML = 'wow!' }); </script> <body> <div id="myowndiv"></div> </body> </html> I would have expected to have to declare and assign myowndiv with document.getElementById("myowndiv"); or $("#myowndiv"); before I could call innerHTML or anything else on it? Is this behaviour by design? Can anyone explain why? My fear is that if I refactor and end up not using .ready() or even using jQuery at all then my code will fail to execute. Cheers!

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  • Dojo's nested BorderContainer disappear in IE

    - by h4b0
    I have this terrible problem with IE 7/8/9. I wrote an app using Dojo toolkit 1.8.0 and Play! framework. It works fine in all browser except for IE. Its 'developers tools' show no error, so does firebug. The problematic code section is here: <div data-dojo-type="dijit.layout.BorderContainer" data-dojo-props="design: 'headline'"> <div data-dojo-type="dijit.layout.ContentPane" id="head" region="top"> </div> <div data-dojo-type="dijit.layout.BorderContainer" data-dojo-props="region: 'center'"> <div data-dojo-type="dijit.layout.ContentPane" id="menu" region="left"> </div> <div data-dojo-type="dijit.layout.BorderContainer" data-dojo-props="region: 'center'"> <div data-dojo-type="dijit.layout.ContentPane" id="content_1" region="top"> </div> <div data-dojo-type="dijit.layout.ContentPane" id="content_2" region="bottom"> </div> </div> </div> <div data-dojo-type="dijit.layout.ContentPane" id="foot" region="bottom"> </div> </div> The result, in all browsers except for IE is like that: But in IE it is shown like that: Can anyone explain why there are such differences? At first I thought that in IE content is hidden, so I set overflow: auto, but no scrollbar appeared after page load.

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  • Add a banner at the top on unknown HTML page on the fly; Send a note to network user

    - by Vi
    I want to be able to send messages to users of network that my computer routes to. Modifying requested pages, by adding messages like Warning: this access point is going down soon" or Network quota exhausted or You are overusing the network connection and may be banned or Security notice: this is unencrypted network, so everybody around can see this page too It seems the only good solution (as there is no general "Send notice to users of my access point" thing). All traffic is already routed through -j REDIRECT, socat and remote SOCSK5 server, so intercepting unencrypted content should be easy. How it's better to add a message? Just inserting <div style="color:white; background-color:red">Sorry, connect_me access point is going down soon...</div> as the first element of <body> breaks design of some pages (f.e. Wikipedia). Should I also add some "Cache-control" directive to prevent persisting such messages? /* smdclient messages are poor solution, as them are Windows-only and can disturb users not using the network */

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  • include ::before pseudo class in javascript

    - by user1955837
    Why is this thing not working? If I remove ::before from javascript and css it works. But due to the design needs there has to be a ::before. How do I point to the class + ::before? $(function () { var sections = $("section"); var navigation_links = $("nav a"); sections.waypoint({ handler: function (event, direction) { var active_section; active_section = $(this); if (direction === "up") active_section = active_section.prev(); var active_link = $('nav a[href="#' + active_section.attr("id") + '"]'); navigation_links.removeClass("selected::before"); active_link.addClass("selected::before"); }, offset: '25%' }) }); css: .selected::before { display: block; content: ""; margin-top: 6px; width: 8px; height: 8px; background: url(../img/sprite.png) -126px -196px; background-size: 400px 480px; float: left; margin-left: 20px; margin-right: 20px; }

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  • Joomla get plugin id

    - by Christian Sciberras
    I wrote a Joomla plugin which will eventually load a library. The path to library is a plugin parameter, as such when the path is incorrect, a message pops up in the backend, together with a link to edit the plugin parameters: /administrator/index.php?option=com_plugins&view=plugin&client=site&task=edit&cid[]=36 See the 36 at the end? That's my plugin's id in the database (table jos_plugins). My issue is that this id changes on installation, ie, on different installs, it would be something else. So I need to find this id programmatically. The problem is that I couldn't find this id from the plugin object itself (as to why not, that would be joomla's arguably short-sighted design decision). So unless you know about some neat trick, (I've checked and double checked JPlugin and JPluginHelper classes), I'll be using the DB. Edit; Some useful links: http://docs.joomla.org/Plugin_Developer_Overview http://api.joomla.org/Joomla-Framework/Plugin/JPlugin.html http://api.joomla.org/Joomla-Framework/Plugin/JPluginHelper.html http://forum.joomla.org/viewtopic.php?p=2227737 Guess I'll be using the wisdom from that last link...

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  • What choices do I have for a future in software development?

    - by user354892
    After graduating from college with a degree in mathematics and a minor in computer science, I took over a year to find my first programming job. I very much enjoy my work environment, but sometimes I feel like I'm not developing professionally as quickly as I am capable of. My company does mostly web programming. The project that I work on is basically a front-end for a SQL database. The entire project is (AFAIK) coded is VB.NET. I've been working on the back-end logic of the program. After some time on the job, we decided that designing web pages is not my cup of tea. It seems like the thing that I spend more time on than anything else is searching the web and SO for information about poorly documented .net and web APIs. This does not make me happy; is this normal for a programming job; I don't think it is. It really hit me the other day when i saw a question about math asked here and I didn't know the answer; I feel like my knowledge is going stale! I was previously almost hired by another company where they design graphic-intensive battle simulations for the military. I sometimes wonder what my life might be like if I had that job. I feel like my math and problem solving skills might have been a better fit at this other company. Within the wide field of software development, there are a number of directions in which to go as evidenced by the huge variety of topics discussed here on StackOverflow. I would like to feel like I'm going in the direction where I will make the most of my skills and have a satisfying career. Let me word this question as clearly as possible: given the wide breadth of the field of software development, how does it break down into sub-fields and what are the considerations for developing a software development career. I do not want to manage my career by default.

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  • Would like some modelling tips for dependent values

    - by orjan
    I'm working on a model for a simple fishing competition and I have some issues with my design. The main class for the fishing game is Capture and it looks like this: public class Capture : Entity { public virtual int Weight { get; set; } public virtual int Length { get; set; } public virtual DateTime DateForCapture { get; set; } public virtual User CapturedBy { get; set; } public virtual Species Species { get; set; } } So far there´s no problem but I'm not really sure how to model the game. Every Species is connected to a reference weight that changes from year to year The number of point for a capture is its Weight divided by the current reference weight for the species. One way to solve the problem is to connect a capture to SpeciesReferenceWeight instead of Species public class SpeciesReferenceWeight : Entity { public virtual Species Species { get; set; } public virtual int ReferenceWeight { get; set; } public virtual int Year { get; set; } } But in that way that Capture is connected to the implementation details of the game and from my point of view a capture is still a capture even if it's not included in a game. The result I'm aiming for is like: http://hornalen.net/fishbonkern/2007/ that I wrote a couple of years ago with brute force sql and no domain model. I would be very happy for all kinds of feeback on this issue.

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  • Objective C - creating concrete class instances from base class depending upon type

    - by indiantroy
    Just to give a real world example, say the base class is Vehicle and concrete classes are TwoWheeler and FourWheeler. Now the type of the vehicle - TwoWheeler or FourWheeler, is decided by the base class Vehicle. When I create an instance of TwoWheeler/FourWheeler using alloc-init method, it calls the super implementation like below to set the value of common properties defined in the Vehicle class and out of these properties one of them is type that actually decides if the type is TwoWheeler or FourWheeler. if (self = [super initWithDictionary:dict]){ [self setOtherAttributes:dict]; return self; } Now when I get a collection of vehicles some of them could be TwoWheeler and others will be FourWheeler. Hence I cannot directly create an instance of TwoWheeler or FourWheeler like this Vehicle *v = [[TwoWheeler alloc] initWithDictionary:dict]; Is there any way I can create an instance of base class and once I know the type, create an instance of child class depending upon type and return it. With the current implementation, it would result in infinite loop because I call super implementation from concrete class. What would be the perfect design to handle this scenario when I don't know which concrete class should be instantiated beforehand?

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  • How to get results efficiently out of an Octree/Quadtree?

    - by Reveazure
    I am working on a piece of 3D software that has sometimes has to perform intersections between massive numbers of curves (sometimes ~100,000). The most natural way to do this is to do an N^2 bounding box check, and then those curves whose bounding boxes overlap get intersected. I heard good things about octrees, so I decided to try implementing one to see if I would get improved performance. Here's my design: Each octree node is implemented as a class with a list of subnodes and an ordered list of object indices. When an object is being added, it's added to the lowest node that entirely contains the object, or some of that node's children if the object doesn't fill all of the children. Now, what I want to do is retrieve all objects that share a tree node with a given object. To do this, I traverse all tree nodes, and if they contain the given index, I add all of their other indices to an ordered list. This is efficient because the indices within each node are already ordered, so finding out if each index is already in the list is fast. However, the list ends up having to be resized, and this takes up most of the time in the algorithm. So what I need is some kind of tree-like data structure that will allow me to efficiently add ordered data, and also be efficient in memory. Any suggestions?

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