Search Results

Search found 44734 results on 1790 pages for 'model based design'.

Page 191/1790 | < Previous Page | 187 188 189 190 191 192 193 194 195 196 197 198  | Next Page >

  • Practical Meta Programming System (MPS)

    - by INTPnerd
    This is in regards to Meta Programming System or MPS by JetBrains. Thus far, from my efforts to learn how to use MPS, I have only learned its basic purpose and that it is very complex. Is MPS worth learning? Is there anyone who already effectively uses MPS to create their own languages and editors for those languages and uses these created editors as their primary way of programming? If so, what types of programs have they made with this? What are the advantages and disadvantages of working with MPS? What is the best way to learn MPS?

    Read the article

  • Is data integrity possible without normalization?

    - by shuniar
    I am working on an application that requires the storage of location information such as city, state, zip code, latitude, and longitude. I would like to ensure: Location data is accurate Detroit, CA Detroit IS NOT in California Detroit, MI Detroit IS in Michigan Cities and states are spelled correctly California not Calefornia Detroit not Detriot Cities and states are named consistently Valid: CA Detroit Invalid: Cali california DET d-town The D Also, since city/zip data is not guaranteed to be static, updating this data in a normalized fashion could be difficult, whereas it could be implemented as a de facto location if it is denormalized. A couple thoughts that come to mind: A collection of reference tables that store a list of all states and the most common cities and zip codes that can grow over time. It would search the database for an exact or similar match and recommend corrections. Use some sort of service to validate the location data before it is stored in the database. Is it possible to fulfill these requirements without normalization, and if so, should I denormalize this data?

    Read the article

  • Low coupling processing big quantities of data

    - by vitalik
    Usually I achieve low coupling by creating classes that exchange lists, sets, and maps between them. Now I am developing a batch application and I can't put all the data inside a data structure because there isn't enough memory. I have to read and process one chunk of data and then going to the next one. So having low coupling is much more difficult because I have to check somewhere if there is still data to read, etc. What I am using now is: Source - Process - Persist The classes that process have to ask to the Source classes if there are more rows to read. What are the best practices and or useful patterns in such situations? I hope I am explaining myself, if not tell me.

    Read the article

  • Integration of routes that are not resources in an MVC REST style application

    - by Emil Lerch
    I would like to keep my application relatively REST-pure for the sake of consistency, but I'm struggling philosophically with the relatively few views (maybe just one) that I'll need to build that don't relate to resources directly, and therefore do not fit into a REST style. As an example, take the home page. Ruby on rails seems to bail on their otherwise RESTful approach for this very basic need of all web sites. The home page appears special: You can get it, but a get at the resource level is supposed to give you a collection of elements. I can imagine this being the list of routes maybe, but that seems a stretch, and doesn't address anything else. Getting the home page by id doesn't seem to make a whole lot of sense - what's the element of a home collection? Again, maybe routes, but a get on a route would do what? Redirect? This feels odd. You can't delete it (arguably you could allow this for administrators) Adding a second one doesn't make sense except possibly if the elements were routes Updating it might make sense for administrators, but AFAIK REST doesn't describe updates on the resource directly, only elements of the resource (this article explicitly says "UNUSED" for PUTS on the resource) Is the "right" thing to do just to special case these types of things? At the end of the day, I can wrap my head around most of applications being gathered around resources...I can't think of another good example other than a home page, but since that's the start of an application, I think it warrants some thought.

    Read the article

  • What is the value in hiding the details through abstractions? Isn't there value in transparency?

    - by user606723
    Background I am not a big fan of abstraction. I will admit that one can benefit from adaptability, portability and re-usability of interfaces etc. There is real benefit there, and I don't wish to question that, so let's ignore it. There is the other major "benefit" of abstraction, which is to hide implementation logic and details from users of this abstraction. The argument is that you don't need to know the details, and that one should concentrate on their own logic at this point. Makes sense in theory. However, whenever I've been maintaining large enterprise applications, I always need to know more details. It becomes a huge hassle digging deeper and deeper into the abstraction at every turn just to find out exactly what something does; i.e. having to do "open declaration" about 12 times before finding the stored procedure used. This 'hide the details' mentality seems to just get in the way. I'm always wishing for more transparent interfaces and less abstraction. I can read high level source code and know what it does, but I'll never know how it does it, when how it does it, is what I really need to know. What's going on here? Has every system I've ever worked on just been badly designed (from this perspective at least)? My philosophy When I develop software, I feel like I try to follow a philosophy I feel is closely related to the ArchLinux philosophy: Arch Linux retains the inherent complexities of a GNU/Linux system, while keeping them well organized and transparent. Arch Linux developers and users believe that trying to hide the complexities of a system actually results in an even more complex system, and is therefore to be avoided. And therefore, I never try to hide complexity of my software behind abstraction layers. I try to abuse abstraction, not become a slave to it. Question at heart Is there real value in hiding the details? Aren't we sacrificing transparency? Isn't this transparency valuable?

    Read the article

  • Is there a language where collections can be used as objects without altering the behavior?

    - by Dokkat
    Is there a language where collections can be used as objects without altering the behavior? As an example, first, imagine those functions work: function capitalize(str) //suppose this *modifies* a string object capitalizing it function greet(person): print("Hello, " + person) capitalize("pedro") >> "Pedro" greet("Pedro") >> "Hello, Pedro" Now, suppose we define a standard collection with some strings: people = ["ed","steve","john"] Then, this will call toUpper() on each object on that list people.toUpper() >> ["Ed","Steve","John"] And this will call greet once for EACH people on the list, instead of sending the list as argument greet(people) >> "Hello, Ed" >> "Hello, Steve" >> "Hello, John"

    Read the article

  • Representation of data in application versus database

    - by user1815201
    I'm going to make an application that will be given data to put in a database. The data will for the most part be the same, but the way it is formatted will vary a lot (could be in anything from text files to .xls to .doc). I'm not a very experienced developer, but I can see some potential issues and I want to minimize them. First off I have decided to use the DAO pattern, so that I can easily support new file formats or file suddenly formatted in different ways. What I really wonder about though, is how I should manage the data itself within my application. I'm thinking that the database DAO should have models representing each table of the database with the same relations between them, to make the uploading process easy. But should the filesystem DAO's have to use the same models? I can imaging that when the database changes, the change will suddenly propagate throughout the entire system, all DAOs and models alike. And that is obviously a bad thing. I'm a little bit tired and out of time. Will update with what ever questions you have. Thanks!

    Read the article

  • Can an aggregate root hold references of members of another aggregate root?

    - by Rushino
    Hello, I know outside aggregates cant change anything inside an aggregate without passing by his root. That said i would like to know if an aggregate root can hold references of members (objects insides) of another aggregate root? (fellowing DDD rules) Example : a Calendar contain a list of phases which contain a list of sequences which contain a list of assignations Calendar is root because phases and sequences and assignations only work in context of a calendar. You also have Students and Groups of student (called groups) It is possible (fellowing DDD rules) to make Groups holding references of assignations or it need to pass by the root for accessing groups from assignations ? Thanks.

    Read the article

  • Databinding to an Entity Framework in WPF

    - by King Chan
    Is it good to use databinding to Entity Framework's Entity in WPF? I created a singleton entity framework context: To have only one connection and it won't open and close all the time. So I can pass the Entity around to any class, and can modify the Entity and make changes to the database. All ViewModels getting the entity out from the same Context and databinding to the View saves me time from mapping new object, but now I imagine there is problem in not using the newest Context: A ViewModel databinding to a Entity, then someone else updated the data. The ViewModel will still display the old data, because the Context is never being dispose to refresh. I always create new Context and then dispose of it. If I want to pass the Entity around, then there will be conflicts between Context and Entity. What is the suggested way of doing this ?

    Read the article

  • Securing iOS or Android Backend API

    - by El Guapo
    I have an application that I am writing for both iOS and Android; this application will be served by a ReSTFUL API running on a cluster of servers on "the internets". I am curious how the rest of the world is going about securing their APIs so only specific applications running on iOS or Android can use these APIs. I could go the same route as other OAuth providers by providing a key/secret combination (2-legged OAuth), however, what do I do if I ever have to change these keys??? Do I create a new key/secret for every person that downloads the app???

    Read the article

  • Callback Contract in WCF

    Callback contracts are a very powerful concept that is easily implemented in WCF. Using this, it is very easy to achieve event-like behavior between a service and client (duplex operations).

    Read the article

  • Designing javascript chart library

    - by coolscitist
    I started coding a chart library on top of d3js: My chart library. I read Javascript API reusability and Towards reusable charts. However, I am NOT really following the suggestions because I am not really convinced about them. This is how my library can be used to create a bubble chart: var chart = new XYBubbleChart(); chart.data = [{"xValue":200,"yValue":300},{"xValue":400,"yValue":200},{"xValue":100,"yValue":310}]; //set data chart.dataKey.x = "xValue"; chart.dataKey.y = "yValue"; chart.elementId = "#chart"; chart.createChart(); Here are my questions: It does not use chaining. Is it a big issue? Every property and function is exposed publicly. (Example: width, height are exposed in Chart.js). OOP is all about abstraction and hiding, but I don't really see the point right now. I think exposing everything gives flexibility to change property and functionality inside subclasses and objects without writing a lot of code. What could be pitfalls of such exposure? I have implemented functions like: zooming, "showing info boxes when data point is clicked" as "abilities". (example: XYZoomingAbility.js). Basically, such "abilities" accept "chart" object, play around with public variables of "chart" to add functionality. What this allows me to do is to add an ability by writing: activateZoomAbility(chartObject); My goal is to separate "visualization" from "interactivity". I want "interactivity" like: zooming to be plugged into the chart rather than built inside the chart. Like, I don't want my bubble chart to know anything about "zooming". However, I do want zoomable bubble chart. What is the best way to do this? How to test and what to test? I have written mixed tests: jasmine and actual html files so that I can test manually on browser.

    Read the article

  • Where do you search/look for game developers for an indie game startup?

    - by G.Campos
    Hey there I just recently saw stackoverflow had a game dev sister site so here I am, wondering if you experienced fellows know where one can search/look for game developers for an indie game startup? In other words: I have a game idea which I've written down with as much detail as possible (so anyone else can understand how it works) and now I'm looking for a heavy php programmer with whom to pair up in order to go from idea to reality. I'm a front-end/interface designer and an intermediate programmer. I recognize my project requires heavy programming skills which I do not have as of today =) So, what websites, communities or places do you recommend I go look into? Where do good programmers interested in indie games go look for projects if they don't have their own? Thanks in advance G.Campos

    Read the article

  • genetic algorithm for leveling/build test

    - by Renan Malke Stigliani
    I'm starting o build a online PVP (duel like, one-to-one) game, where there is leveling, skill points, special attacks and all the common stuff. Since I never did anything like that, I'm still thinking about the maths behind the level/skill/special balances. So I thought good way of testing the best/combo builds would implement a Genetic Algorith. It'd be like that: Generate a big portion of random characters Make them fight, level them up accordingly to the victories(more XP)/losses(less XP) Mate the winners, crossing their builds, to try to make even best characters Add some more random chars, emulating new players Repeat the process for some time, or util find some chars who can beat everyone butts So I could play with the math and try to find the balance where the top x% chars would be a mix of various build types. So, is it a good idea, or there are some other easier method to do the balance? PS: I like this also, because it sounds funny

    Read the article

  • Scene Graph Traversing Techniques

    - by Bunkai.Satori
    Scene Graph seems to be the most effective way of representing the game world. The game world usually tends to be as large as the memory and device can handle. In contrast, the screen of the device captures only a fraction of the Game World/Scene Graph. Ideally, I wish to process(update and render) only the visible game objects/nodes on per-frame basis. My question therefore is, how to traverse the scene graph so, that I will focus only on the game notes that are in the camera frustum? How to organize data so that I can easily focus only on the scene graph nodes visible to me? What are techniques to minimize scenegraph traversal time? Is there such way as more effective traversal, or do I have to traverse whole scene graph on per-frame basis?

    Read the article

  • Responsive website VS mobile website

    - by Saif Bechan
    I am creating a new blog. Nowadays, especially for a blog, it's important that the websites are accessible for all devices. Now I have to make a choice on what to do. I have seen 2 options. Option 1 is to go with a normal fixed website, for example 960px wide (grid960). And for mobile users have a mobile version. This takes some more time, but then there are 2 good versions of the website. Option 2 I haven't seen a lot yet, creating a adaptive website, or also called responsive website. I am now looking into the LESS framework, where the website automatically switches to to required width. Only downside is that when the normal browser is re-sized, everything re-sizes. Another problem I found is that pinch-to-zoom on devices does not work. Now the question is, which one would you prefer for a blog. One that constantly changes layout when you move your device, or one where you have the choice to view mobile and normal. If there are any other options, please let me know.

    Read the article

  • S#arp Architecture 1.5.1 released

    - by AlecWhittington
    So far we have had some great success with the 1.5 release of S#arp Architecture, but there were a few issues that made it into the release that needed to be corrected. These issues were: Unnecessary assemblies in the root /bin and SolutionItemsContainer folders Nant folder removed from root /bin - this was causing issues with the build scripts that come with the project if the user did not have Nant installed and available via a path variable VS 2010 template - the CrudScaffoldingForEnterpriseApp...(read more)

    Read the article

  • Will it hurt my website's SEO friendliness if I host a french targetted website at, let's say, godaddy.com?

    - by Suraj
    Hi guys, I have read that the server location is important for a website to be SEO friendly. I am planning to build a website from scratch which is targetted mainly to french audience (in france), but I am planning to host the web site at godaddy.com. My concern is will it hurt the website SEO friendliness? Or do you recommend me to host the website in france itself? I have also read that I need to have a static IP Address. If it's true, can anyone explain me for what reason? Can anyone suggest me some good web hosting companies, prefereable in france? Thanks in advance!

    Read the article

  • Extracting Data from a Source System to History Tables

    - by Derek D.
    This is a topic I find very little information written about, however it is very important that the method for extracting data be done in a way that does not hinder performance of the source system.  In this example, the goal is to extract data from a source system, into another database (or server) all [...]

    Read the article

  • Configuration data: single-row table vs. name-value-pair table

    - by Heinzi
    Let's say you write an application that can be configured by the user. For storing this "configuration data" into a database, two patterns are commonly used. The single-row table CompanyName | StartFullScreen | RefreshSeconds | ... ---------------+-------------------+------------------+-------- ACME Inc. | true | 20 | ... The name-value-pair table ConfigOption | Value -----------------+------------- CompanyName | ACME Inc. StartFullScreen | true (or 1, or Y, ...) RefreshSeconds | 20 ... | ... I've seen both options in the wild, and both have obvious advantages and disadvantages, for example: The single-row tables limits the number of configuration options you can have (since the number of columns in a row is usually limited). Every additional configuration option requires a DB schema change. In a name-value-pair table everything is "stringly typed" (you have to encode/decode your Boolean/Date/etc. parameters). (many more) Is there some consensus within the development community about which option is preferable?

    Read the article

  • What's wrong with JavaScript

    - by ts01
    There is a lot of buzz around Dart recently, often questioning Google motivations and utility of Dart as replacement for JavaScript. I was searching for rationale of creating Dart rather than investing more effort in ECMAScript. In well known leaked mail its author is saying that Javascript has historical baggage that cannot be solved without a clean break. But there is only one concrete example given (apart of performance concerns) of "fundamental language problems", which is an existence of a single Number primitive So, my questions are: How an existence of a single Number primitive can be a "fundamental problem"? Are there other known "fundamental problems" in JavaScript?

    Read the article

  • What are current Biggest Challenges faced by Ecommerce Applications ?

    - by Rachel
    I am in the process to start Product Development for E-commerce and Online Retail domain but before starting I would like to know what are the biggest challenges faced by current state of Art E-Commerce Application ? Also I have not experience building e-commerce products and so what things should I keep in mind before developing one ? Is there are books, articles, blogs outside which I should refer to gain some knowledge before starting out ? Update: What are you thoughts on the recommendation engines for ecommerce applications ? What challenges we have with current state of recommendations engines for ecommerce web application and how can we overcome them ?

    Read the article

  • Cluster Nodes as RAID Drives

    - by BuckWoody
    I'm unable to sleep tonight so I thought I would push this post out VERY early. When you don't sleep your mind takes interesting turns, which can be a good thing. I was watching a briefing today by a couple of friends as they were talking about various ways to arrange a Windows Server Cluster for SQL Server. I often see an "active" node of a cluster with a "passive" node backing it up. That means one node is working and accepting transactions, and the other is not doing any work but simply "standing by" waiting for the first to fail over. The configuration in the demonstration I saw was a bit different. In this example, there were three nodes that were actively working, and a fourth standing by for all three. I've put configurations like this one into place before, but as I was looking at their architecture diagram, it looked familar - it looked like a RAID drive setup! And that's not a bad way to think about your cluster arrangements. The same concerns you might think about for a particular RAID configuration provides a good way to think about protecting your systems in general. So even if you're not staying awake all night thinking about SQL Server clusters, take this post as an opportunity for "lateral thinking" - a way of combining in your mind the concepts from one piece of knowledge to another. You might find a new way of making your technical environment a little better. Share this post: email it! | bookmark it! | digg it! | reddit! | kick it! | live it!

    Read the article

  • Adventures in the Land of CloudDB/NoSQL/NoAcid

    - by KKline
    Cloud, Bunny, or CloudBunny? Last year, some of my friends from Quest Software attended Hadoop World in New York. In 2009, I never would've guessed that Quest would be there with products, community initiatives, as a major sponsor and with presenters? There were just under 1,000 attendees who weren’t the typical devheads and geekasaurs you'd normally see at very techie events like Code Camps, SQL Saturdays, Cloud Camps and or even other NoSQL events such as the Cassandra Summit. We're talkin' enterprise...(read more)

    Read the article

  • ASP.NET MVC: Moving code from controller action to service layer

    - by DigiMortal
    I fixed one controller action in my application that doesn’t seemed good enough for me. It wasn’t big move I did but worth to show to beginners how nice code you can write when using correct layering in your application. As an example I use code from my posting ASP.NET MVC: How to implement invitation codes support. Problematic controller action Although my controller action works well I don’t like how it looks. It is too much for controller action in my opinion. [HttpPost] public ActionResult GetAccess(string accessCode) {     if(string.IsNullOrEmpty(accessCode.Trim()))     {         ModelState.AddModelError("accessCode", "Insert invitation code!");         return View();     }       Guid accessGuid;       try     {         accessGuid = Guid.Parse(accessCode);     }     catch     {         ModelState.AddModelError("accessCode", "Incorrect format of invitation code!");         return View();                    }       using(var ctx = new EventsEntities())     {         var user = ctx.GetNewUserByAccessCode(accessGuid);         if(user == null)         {             ModelState.AddModelError("accessCode", "Cannot find account with given invitation code!");             return View();         }           user.UserToken = User.Identity.GetUserToken();         ctx.SaveChanges();     }       Session["UserId"] = accessGuid;       return Redirect("~/admin"); } Looking at this code my first idea is that all this access code stuff must be located somewhere else. We have working functionality in wrong place and we should do something about it. Service layer I add layers to my application very carefully because I don’t like to use hand grenade to kill a fly. When I see real need for some layer and it doesn’t add too much complexity I will add new layer. Right now it is good time to add service layer to my small application. After that it is time to move code to service layer and inject service class to controller. public interface IUserService {     bool ClaimAccessCode(string accessCode, string userToken,                          out string errorMessage);       // Other methods of user service } I need this interface when writing unit tests because I need fake service that doesn’t communicate with database and other external sources. public class UserService : IUserService {     private readonly IDataContext _context;       public UserService(IDataContext context)     {         _context = context;     }       public bool ClaimAccessCode(string accessCode, string userToken, out string errorMessage)     {         if (string.IsNullOrEmpty(accessCode.Trim()))         {             errorMessage = "Insert invitation code!";             return false;         }           Guid accessGuid;         if (!Guid.TryParse(accessCode, out accessGuid))         {             errorMessage = "Incorrect format of invitation code!";             return false;         }           var user = _context.GetNewUserByAccessCode(accessGuid);         if (user == null)         {             errorMessage = "Cannot find account with given invitation code!";             return false;         }           user.UserToken = userToken;         _context.SaveChanges();           errorMessage = string.Empty;         return true;     } } Right now I used simple solution for errors and made access code claiming method to follow usual TrySomething() methods pattern. This way I can keep error messages and their retrieval away from controller and in controller I just mediate error message from service to view. Controller Now all the code is moved to service layer and we need also some modifications to controller code so it makes use of users service. I don’t show here DI/IoC details about how to give service instance to controller. GetAccess() action of controller looks like this right now. [HttpPost] public ActionResult GetAccess(string accessCode) {     var userToken = User.Identity.GetUserToken();     string errorMessage;       if (!_userService.ClaimAccessCode(accessCode, userToken,                                       out errorMessage))     {                       ModelState.AddModelError("accessCode", errorMessage);         return View();     }       Session["UserId"] = Guid.Parse(accessCode);     return Redirect("~/admin"); } It’s short and nice now and it deals with web site part of access code claiming. In the case of error user is shown access code claiming view with error message that ClaimAccessCode() method returns as output parameter. If everything goes fine then access code is reserved for current user and user is authenticated. Conclusion When controller action grows big you have to move code to layers it actually belongs. In this posting I showed you how I moved access code claiming functionality from controller action to user service class that belongs to service layer of my application. As the result I have controller action that coordinates the user interaction when going through access code claiming process. Controller communicates with service layer and gets information about how access code claiming succeeded.

    Read the article

< Previous Page | 187 188 189 190 191 192 193 194 195 196 197 198  | Next Page >