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• Mozilla Persona to the login rescue?

  - by Matt Watson

  A lot of website now allow us to login or create accounts via OAuth or OpenID. We can use our Facebook, Twitter, Google, Windows Live account and others. The problem with a lot of these is we have to have allow the websites to then have access to our account and profile data that they shouldn't really have. Below is a Twitter authorization screen for example when signing in via Technorati. Now Technorati can follow new people, update my profile and post tweets? All I wanted to do was login to Technorati.com to comment on a post!Mozilla has just released their new solution for this called Persona. First thought is oh great another solution! But they are actually providing something a little different and better. It is based on an email address and isn't linked to anything like our personal social networks or their information. Persona only exists to help with logging in to websites. No loose strings attached.Persona is based on a new standard called BrowserID and you can read more about it here:How BrowserID Works.  The goal is to integrate BrowserID in to the browser at a deeper level so no password entry is required at all. You can tell your web browser to just auto sign in for you. I am really hoping this takes off and will look at implementing it in current projects! I would recommend researching it and lets hope it or something like it becomes a wide spread reality in the future.

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• Is it possible to use 3G internet for a TCP/IP game server?

  - by Amit Ofer

  I'm working on a turned based multiplayer android game with a friend. I started working on the game server and client using socket programming. I found a few tutorials on how to implement a basic chat on android and I started extending that example to suit my needs. Basically the game is really simple and the communication only include sending a few string from the client to the server every turn and sending the calculated scores back to all the clients after each turn. the idea is that one of the players creates the game and thus initialize the server, and each player connects to this client using ip. I tried this solution and it seems to work great when all the players are using the same wifi connection or by using router port forwarding. The problem is when trying to use 3G internet for the server, I guess the problem is that 3G ip address isn't global and you can't use port forwarding there, correct me if I'm wrong here. Is there a way to overcome this issue? or the only solution is to limit my game to wifi only or think of a different solution than the standard socket programming solution? I.E web server etc. what do you think would be the best approach here? Thanks.

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• Google Analytics: Do unique events report as unique visits when triggered on pages other than your own domain?

  - by Jesse Gardner

  We just recently attached a SWF to our Brightcove video player to report various events back to Google Analytics. We're also tracking page views with a standard GA snippet on the page where the player is embedded. As I understand it, because a unique has already been recorded for the page, any event being triggered by the player is getting associated with that unique. However, we allow people to embed the video player on other websites. All of the event data started pouring into the Events section as expected, but we noticed a dramatic uptick in unique visitors on the site (nearly double) while the pageview count stayed relatively unchanged. Disabling event tracking brought the traffic back down to average levels. I should also add that in the Pages section of Event tracking we're seeing URLs for other sites where the player has been embedded; but this data isn't showing up in the Content section. It seems counterintuitive, but does GA count an event fired as a unique visit even if it's triggered from some place other than your website? Is so, there any way to trigger an event in the events section without it reporting to the unique visitor count?

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• Using a random string to authenticate HMAC?

  - by mrwooster

  I am designing a simple webservice and want to use HMAC for authentication to the service. For the purpose of this question we have: a web service at example.com a secret key shared between a user and the server [K] a consumer ID which is known to the user and the server (but is not necessarily secret) [D] a message which we wish to send to the server [M] The standard HMAC implementation would involve using the secret key [K] and the message [M] to create the hash [H], but I am running into issues with this. The message [M] can be quite long and tends to be read from a file. I have found its very difficult to produce a correct hash consistently across multiple operating systems and programming languages because of hidden characters which make it into various file formats. This is of course bad implementation on the client side (100%), but I would like this webservice to be easily accessible and not have trouble with different file formats. I was thinking of an alternative, which would allow the use a short (5-10 char) random string [R] rather than the message for autentication, e.g. H = HMAC(K,R) The user then passes the random string to the server and the server checks the HMAC server side (using random string + shared secret). As far as I can see, this produces the following issues: There is no message integrity - this is ok message integrity is not important for this service A user could re-use the hash with a different message - I can see 2 ways around this Combine the random string with a timestamp so the hash is only valid for a set period of time Only allow each random string to be used once Since the client is in control of the random string, it is easier to look for collisions I should point out that the principle reason for authentication is to implement rate limiting on the API service. There is zero need for message integrity, and its not a big deal if someone can forge a single request (but it is if they can forge a very large number very quickly). I know that the correct answer is to make sure the message [M] is the same on all platforms/languages before hashing it. But, taking that out of the equation, is the above proposal an acceptable 2nd best?

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• CSOM (Client Side Object Model) - What's new with SharePoint 2013

  - by KunaalKapoor

  SharePoint CSOMThe Client-Side Object Model or CSOM came out with SharePoint 2010. CSOM is accessible through client.svc but all client.svc calls must go through supported WFC entry points (supported entry points are .NET, Silverlight and JavaScript). So a developer would need to use client side proxy objects exposed by either a .NET assembly or a JavaScript library. Changes with SharePoint 2013REST Capabilities - Direct access to client.svcNew APIs - App ModelREST CapabilitiesOne of the most important changes to the CSOM with SharePoint 2013 is that the web service entry point of client.svc has been extended to allow direct access  via REST-Based web service calls. This is a really critical change since its going to make the SharePoint platform accessible to any other platform, opening the horizons of integration and collaboration with other REST based platforms and devices. OData (a really popular standard data access API for HTTP-based clients) is supported similar to 2010 but will be a more important aspect of SharePoint 2013 development.New API'sCSOM for SharePoint 2013 has been buffed up with several new APIs for not only SharePoint server functionality but also an API for Windows Phone applications. For a SharePoint 2010 farm most of the new APIs mentioned below are available only via server side APIs:SearchTaxonomyPublishingWorkflowUser ProfilesE-DiscoveryAnalyticsBusiness DataIRMFeedsSharePoint 2013 remote APIs being accessible through both CSOM and REST is very important to the new app model where developers can no longer run code in a SharePoint environment nor can they access the server-side APIs. So CSOM plays the savior here.Also, you can now substitute the alias '_api' in order to reference '_vti_bin/client.svc'.

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• How far should one take e-mail address validation?

  - by Mike Tomasello

  I'm wondering how far people should take the validation of e-mail address. My field is primarily web-development, but this applies anywhere. I've seen a few approaches: simply checking if there is an "@" present, which is dead simply but of course not that reliable. a more complex regex test for standard e-mail formats a full regex against RFC 2822 - the problem with this is that often an e-mail address might be valid but it is probably not what the user meant DNS validation SMTP validation As many people might know (but many don't), e-mail addresses can have a lot of strange variation that most people don't usually consider (see RFC 2822 3.4.1), but you have to think about the goals of your validation: are you simply trying to ensure that an e-mail address can be sent to an address, or that it is what the user probably meant to put in (which is unlikely in a lot of the more obscure cases of otherwise 'valid' addresses). An option I've considered is simply giving a warning with a more esoteric address but still allowing the request to go through, but this does add more complexity to a form and most users are likely to be confused. While DNS validation / SMTP validation seem like no-brainers, I foresee problems where the DNS server/SMTP server is temporarily down and a user is unable to register somewhere, or the user's SMTP server doesn't support the required features. How might some experienced developers out here handle this? Are there any other approaches than the ones I've listed? Edit: I completely forgot the most obvious of all, sending a confirmation e-mail! Thanks to answerers for pointing that one out. Yes, this one is pretty foolproof, but it does require extra hassle on the part of everyone involved. The user has to fetch some e-mail, and the developer needs to remember user data before they're even confirmed as valid.

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• Encapsulating code in F# (Part 2)

  - by MarkPearl

  In part one of this series I showed an example of encapsulation within a local definition. This is useful to know so that you are aware of the scope of value holders etc. but what I am more interested in is encapsulation with regards to generating useful F# code libraries in .Net, this is done by using Namespaces and Modules. Lets have a look at some C# code first… using System; namespace EncapsulationNS { public class EncapsulationCLS { public static void TestMethod() { Console.WriteLine("Hello"); } } } Pretty simple stuff… now the F# equivalent…. namespace EncapsulationNS module EncapsulationMDL = let TestFunction = System.Console.WriteLine("Hello") ()   Even easier… lets look at some specifics about F# namespaces… Namespaces are open. meaning you can have multiple source files and assemblies can contribute to the same namespace. So, Namespaces are a great way to group modules together, so the question needs to be asked, what role do modules play. For me, the F# module is in many ways similar to the vb6 days of modules. In vb6 modules were separate files and simply allowed us to group certain methods together. I find it easier to visualize F# modules this way than to compare them to the C# classes. However that being said one is not restricted to one module per file – there is flexibility to have multiple modules in one code file however with my limited F# experience I would still recommend using the file as the standard level of separating modules as it is very easy to then find your way around a solution. An important note about interop with F# and other .Net languages. I wrote a blog post a while back about a very basic F# to C# interop. If I were to reference an F# library in a C# project (for instance ‘TestFunction’), in C# it would show this method as a static method call, meaning I would not have to instantiate an instance of the module.

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• Multi Threading - How to split the tasks

  - by Motig

  if I have a game engine with the basic 'game engine' components, what is the best way to 'split' the tasks with a multi-threaded approach? Assuming I have the standard components of: Rendering Physics Scripts Networking And a quad-core, I see two ways of multi-threading: Option A ('Vertical'): Using this approach I can allow one core for each component of the engine; e.g. one core for the Rendering task, one for the Physics, etc. Advantages: I do not need to worry about thread-safety within each component I can take advantage of special optimizations provided for single-threaded access (e.g. DirectX offers a flag that can be set to tell it that you will only use single-threading) Option B ('Horizontal'): Using this approach, each task may be split up into 1 <= n <= numCores threads, and executed simultaneously, one after the other. Advantages: Allows for work-sharing, i.e. each thread can take over work still remaining as the others are still processing I can take advantage of libraries that are designed for multi-threading (i.e. ... DirectX) I think, in retrospect, I would pick Option B, but I wanted to hear you guys' thoughts on the matter.

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• Randomly and uniquely iterating over a range

  - by Synetech

  Say you have a range of values (or anything else) and you want to iterate over the range and stop at some indeterminate point. Because the stopping value could be anywhere in the range, iterating sequentially is no good because it causes the early values to be accessed more often than later values (which is bad for things that wear out), and also because it reduces performance since it must traverse extra values. Randomly iterating is better because it will (on average) increase the hit-rate so that fewer values have to be accessed before finding the right one, and also distribute the accesses more evenly (again, on average). The problem is that the standard method of randomly jumping around will result in values being accessed multiple times, and has no automatic way of determining when each value has been checked and thus the whole range has been exhausted. One simplified and contrived solution could be to make a list of each value, pick one at random, then remove it. Each time through the loop, you pick one fromt he set of remaining items. Unfortunately this only works for small lists. As a (forced) example, say you are creating a game where the program tries to guess what number you picked and shows how many guess it took. The range is between 0-255 and instead of asking Is it 0? Is it 1? Is it 2?…, you have it guess randomly. You could create a list of 255 numbers, pick randomly and remove it. But what if the range was between 0-232? You can’t really create a 4-billion item list. I’ve seen a couple of implementations RNGs that are supposed to provide a uniform distribution, but none that area also supposed to be unique, i.e., no repeated values. So is there a practical way to randomly, and uniquely iterate over a range?

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• Corporate Efficiency

  - by AndyScott

  Thoughts on streamlining the process of getting someone up to speed when they join a project as a new hire; or as is common in some companies, switch from one project to another: Has anyone heard of a strategy (including emphasis towards consistent, ongoing documentation) that would bring a user up to speed quickly? Has there been any thought given to focused documentation, specific to a role within a project? Or formalized mentoring within a project, that goes beyond a “system walkthrough”?   Often it's overlooked what time is wasted when a senior level worker is brought on board.  It's assumed that they will know the right questions to ask. They are the type of people that normally learn quickly, and in their own ways, so let them get by with what's out there.   Having a user without a computer will cost you measurable worker hours, making it an easy target to shoot at (and rightly so). Not getting them up to speed as quickly as possible is an efficiency issue, that seems to have become an industry standard as an accepted loss. Given the complexity of the projects within most companies, and the frequency with which users are shifted from one project to another based on need; I think this is an area that bears consideration.

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• Ubuntu server is dropping SSH connections, then not allowing me to log back on

  - by wilhil

  I have an ESX box which I have loaded with two Ubuntu Server machines. During setup, I chose no additional packages to install as I just wanted a lightweight machine for testing. The first thing I did was change the root password via sudo passwd After ESX got on my nerves through lag, I decided to install OpenSSH via apt-get install openssh-server. It did it's business, and I then opened putty and could connect in to both machines fine. The first time it connected, it asked me to add the ssh key as obviously it did not know it. Anyway, the second server is working flawlessly, but, the first seems to be giving me trouble. I was in the middle of typing a sentence when it kicked me off for no reason and when I tried to reconnect, putty gave me a warning that the ssh key had changed and it is potentially dangerous. I attempted to log in anyway and it did not work, just the standard access denied message. Using the second machine, I SSHed in to the first machine and it worked straight away, I then killed the SSH sessions (and possibly SSH server), I then reconnected via putty and I again received the security warning message, but, it allowed me to log on fine. ... I thought "glitch" and nothing more of it, but, it just happened again! I really do not understand this and was hoping someone here can help?

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• How to implement Restricted access to application features

  - by DroidUser

  I'm currently developing a web application, that provides some 'service' to the user. The user will have to select a 'plan' according to which she/he will be allowed to perform application specific actions but up to a limit defined by the plan. A Plan will also limit access to certain features, which will not be available at all for some plans. As an example : say there are 3 plans, 2 actions throughout the application users in plan-1 can perform action-1 3 times, and they can't perform action-2 at all users in plan-2 can perform action-1 10 times, action-2 5 times users in plan-3 can perform action-1 20 times, action-2 10 times So i'm looking for the best way to get this done, and my main concerns besides implementing it, are the following(in no particular order) maintainability/changeability : the number of plans, and type of features/actions will change in the final product industry standard/best practice : for future readiness!! efficiency : ofcourse, i want fast code!! I have never done anything like this before, so i have no clue about how do i go about implementing these functionalities. Any tips/guides/patterns/resources/examples? I did read a little about ACL, RBAC, are they the patterns that i need to follow? Really any sort of feedback will help.

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• How do I get HDMI output working on a Dell XPS 15 L502x?

  - by Jones

  Recently I've bought my dream's notebook, a Dell XPS 15 but since then this dream became a kind of endless nightmare. I'm almost getting crazy to make my graphic card driver work properly, but it seems to be just impossible. Yes, I have a 2GB NVIDIA GeForce GT 540m (Optimus) in it! It simply doesn't work. Every time I generate the xorg.conf Ubuntu hangs on while starting up, which forces me to remove this file to be able to start the notebook with the standard graphic settings. Another problem is that the Dell XPS 15 does NOT have a VGA output, but a HDMI. So, to be able to use a second monitor I have to configure it by the NVIDIA X Server Settings, which just works if the driver is properly initialized with the xorg.conf. I've also tried to make it work with the Bumblebee, but unfortunately it didn't help me much with the HDMI output. Do you guys have any idea to solve this deadlock? Is there any way for me to use my second monitor?

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• Logging Output of Azure Startup Tasks to the Event Log

  - by Your DisplayName here!

  This can come in handy when troubleshooting: using System; using System.Diagnostics; using System.Text;   namespace Thinktecture.Azure {     class Program     {         static EventLog _eventLog = new EventLog("Application", ".", "StartupTaskShell");         static StringBuilder _out = new StringBuilder(64);         static StringBuilder _err = new StringBuilder(64);           static int Main(string[] args)         {             if (args.Length != 1)             {                 Console.WriteLine("Invalid arguments: " + String.Join(", ", args));                 _eventLog.WriteEntry("Invalid arguments: " + String.Join(", ", args));                                 return -1;             }               var task = args[0];               ProcessStartInfo info = new ProcessStartInfo()             {                 FileName = task,                 WorkingDirectory = Environment.CurrentDirectory,                 UseShellExecute = false,                 ErrorDialog = false,                 CreateNoWindow = true,                 RedirectStandardOutput = true,                 RedirectStandardError = true             };               var process = new Process();             process.StartInfo = info;               process.OutputDataReceived += (s, e) =>                 {                     if (e.Data != null)                     {                         _out.AppendLine(e.Data);                     }                 };             process.ErrorDataReceived += (s, e) =>                 {                     if (e.Data != null)                     {                         _err.AppendLine(e.Data);                     }                 };               process.Start();             process.BeginOutputReadLine();             process.BeginErrorReadLine();             process.WaitForExit();               var outString = _out.ToString();             var errString = _err.ToString();               if (!string.IsNullOrWhiteSpace(outString))             {                 outString = String.Format("Standard Out for {0}\n\n{1}", task, outString);                 _eventLog.WriteEntry(outString, EventLogEntryType.Information);             }               if (!string.IsNullOrWhiteSpace(errString))             {                 errString = String.Format("Standard Err for {0}\n\n{1}", task, errString);                 _eventLog.WriteEntry(errString, EventLogEntryType.Error);             }               return 0;         }     } } You then wrap your startup tasks with the StartupTaskShell and you’ll be able to see stdout and stderr in the application event log.

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• SEO questions about PR, Page Structure, and Other

  - by jasondavis

  A couple of basic questions related to SEO. 1) If I have a site that has several different niches that I am trying to promote from. Example Web Developer broke down into section of Web Design, Graphic Design, Programming, Software for SEO purposes, would it be better to use subdomains for these main sections or use the main domain with a folder like structure? 2) Is PR different for each page of a domain or ever page has a PR of the same on that domain? Also do sub-domains have a different PR? 3) When entering a hugely over saturated niche such as web-design, is it even possible to compete with the big sites that have been ranked on google #1 page for years? 4) Lastly, I have read about how important titles, link anchors, and headings are for SEO and how content is the most important. So left's say we are building a standard header, body, sidebar, footer page. In the the actual markup, would it be better to make sure the main content comes before the sidebar on the page or does this probably not make a difference? 5) I seen mentioned in another answer here that microformats can help with SEO, is there any fact behind this? Thank you for any info on this

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• design an extendible and pluggable business logic flow handler in php

  - by Broncha

  I am working on a project where I need to allow a pluggable way to inject business processes in the normal data flow. eg There is an ordering system. The standard flow of the application is A consumer orders an item. Pays for it and card is authorized. Admin captures the payment. Order is marked as complete and item is shipped. But this process may vary (extra steps in between) for different clients. Say a client would need to validate the location of the consumer before he is presented with a credit card form, OR his policies might require some other processes in between. I am thinking of using State Pattern for processing orders, saving the current state of the order in database, and initializing the state of order from the saved state. I would also need some mechanism, where a small plugin would be able to inject business specific states in the state machine. Am I thinking the right way? Are there already implemented patterns for this kind of situation? I am working with Codeigniter and basically this would mean for me, to redirect to proper controller according to the current state of the order. Like, if the state of the order is unconfirmed then redirect the user to details page and then change the state to pending. If some client would need to do some validation, then register an intermediate state between unconfirmed and pending Please suggest.

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• Unity gizmos vs. referenced game objects

  - by DuckMaestro

  I'm designing a Unity script that I intend to be highly reusable and as easy as possible to setup within the editor. To this end, a number of properties of this script really need some kind of visual representation on screen. It is an unresolved question to me whether the design of the script should require references to placeholder game objects, OR just Vector3's and float's that have associated gizmos drawn for them. Normally a gizmo would be a natural choice, except that Unity gizmos are not directly manipulable (as far as I can tell). Because of this shortcoming I'm having to consider whether depending on references to placeholder game objects is a more designer-friendly approach ultimately, in spite of the extra setup required, and that it might be counter-intuitive when the placeholder game objects disappear at run-time (which my script would do). Is there a community standard or preference here in this case? Can a Unity-experienced game programmer / designer speak to which approach they feel is more intuitive or more convenient to setup, when using a 3rd party script? Or is this just splitting hairs as long as I ship an example prefab with my script?

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• How to reset the language of the package descriptions

  - by xubuntix

  I have had German as my main language about a year ago. Later I changed it to English. Most parts of the system accepted the change. The notable exceptions are the package descriptions, which remain in German for some packages. You can see in the image (apt-cache and software-center), that while some descriptions are in English, some have remained in German. So the question is: how do I reset this? I guess that there is somewhere a description cache that needs to be told that it should update all descriptions? EDIT: As asked: the output of some language related commands: $ cat /etc/default/locale LANG="en_US.UTF-8" $ apt-config dump | grep Lang Acquire::Languages ""; Acquire::Languages:: "de_DE"; Acquire::Languages:: "de"; Acquire::Languages:: "en"; Acquire::Languages:: "none"; $ locale LANG=de_DE.UTF-8 LANGUAGE=en LC_CTYPE="de_DE.UTF-8" LC_NUMERIC="de_DE.UTF-8" LC_TIME="de_DE.UTF-8" LC_COLLATE="de_DE.UTF-8" LC_MONETARY="de_DE.UTF-8" LC_MESSAGES="de_DE.UTF-8" LC_PAPER="de_DE.UTF-8" LC_NAME="de_DE.UTF-8" LC_ADDRESS="de_DE.UTF-8" LC_TELEPHONE="de_DE.UTF-8" LC_MEASUREMENT="de_DE.UTF-8" LC_IDENTIFICATION="de_DE.UTF-8" LC_ALL= As a note: I'm not sure what each entry means, but some of the de_DE.UTF-8 are probably ok, since I do want paper-sizes, monetary, time, etc. in standard German formats.

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• Quoted on MVA Voices

  A couple of weeks ago, I received an email from the Dean of Microsoft Virtual Academy (MVA) asking for permission to quote a statement I made during a jump start. Following is an excerpt from that request: "Dear Jochen, I would like to thank you for providing insight as to how the Advanced HTML5 Jump Start helped you improve your skills.  I mentioned this to the leadership team at MVA, and they were pleased to hear this so much that they would like your permission to use a quote from your email to me on the MVA website." Of course! I really enjoy those free MVA jump starts - live and later the recordings. Actually, I prefer the live ones because you really have a chance to communicate with the MVA studio team and the experts in the chat. Luckily, the live stream is provided in two quality levels and with the remote situation of Mauritius, I always have to switch to 'Standard Quality' to avoid too much buffering and to enjoy a smooth experience. Later on, the recordings are great for rehearsal and repetition of the material. You can download and watch them offline while commuting, or what I'm going to do in the future - to use them as material for a study group within the Mauritius Software Craftsmanship Community (MSCC). For sure, this is going to be a lot of fun, and I'm looking forward to work with other Windows-oriented software craftsmen in order to 'push' them towards Microsoft certifications. By chance, I discovered today that my quote has been published in the MVA Voices section: Click to enlarge: Screenshot of Microsoft Virtual Academy web site taken on 04.07.2013 Thank you very much, MVA - this made my day and I'm very happy to be quoted.

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• Use decorator and factory together to extend objects?

  - by TheClue

  I'm new to OOP and design pattern. I've a simple app that handles the generation of Tables, Columns (that belong to Table), Rows (that belong to Column) and Values (that belong to Rows). Each of these object can have a collection of Property, which is in turn defined as an enum. They are all interfaces: I used factories to get concrete instances of these products, depending on circumnstances. Now I'm facing the problem of extending these classes. Let's say I need another product called "SpecialTable" which in turn has some special properties or new methods like 'getSomethingSpecial' or an extended set of Property. The only way is to extend/specialize all my elements (ie. build a SpecialTableFactory, a SpecialTable interface and a SpecialTableImpl concrete)? What to do if, let's say, I plan to use standard methods like addRow(Column column, String name) that doesn't need to be specialized? I don't like the idea to inherit factories and interfaces, but since SpecialTable has more methods than Table i guess it cannot share the same factory. Am I wrong? Another question: if I need to define product properties at run time (a Table that is upgraded to SpecialTable at runtime), i guess i should use a decorator. Is it possible (and how) to combine both factory and decorator design? Is it better to use a State or Strategy pattern, instead?

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• Why is quicksort better than other sorting algorithms in practice?

  - by Raphael

  This is a repost of a question on cs.SE by Janoma. Full credits and spoils to him or cs.SE. In a standard algorithms course we are taught that quicksort is O(n log n) on average and O(n²) in the worst case. At the same time, other sorting algorithms are studied which are O(n log n) in the worst case (like mergesort and heapsort), and even linear time in the best case (like bubblesort) but with some additional needs of memory. After a quick glance at some more running times it is natural to say that quicksort should not be as efficient as others. Also, consider that students learn in basic programming courses that recursion is not really good in general because it could use too much memory, etc. Therefore (and even though this is not a real argument), this gives the idea that quicksort might not be really good because it is a recursive algorithm. Why, then, does quicksort outperform other sorting algorithms in practice? Does it have to do with the structure of real-world data? Does it have to do with the way memory works in computers? I know that some memories are way faster than others, but I don't know if that's the real reason for this counter-intuitive performance (when compared to theoretical estimates).

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• How to fix Black screen?

  - by stupidwhiteguy

  so I recently had my question deleted and merged into a standard how to for blank screens. I am relatively new to This type of computer work and i don't understand the steps nessary to diagnose my problem well enough to solve it so this help full how to has me feeling helpless I can use Ctrl + Alt +F1 and log in So how do I use sudo commands to fix the blank screen on my old dell? sudo lsoci -nn tells me my video card is a ATI rage 128 pro ultra tf /var/log/Xorg.0.log tells me Permission denied that is all i get Sudo apt-get install --reinstall unity tried thay also have also tried Apt-get update and upgrade Please dont close this question without providing an actual answer or if you think it is an exact duplicate provide a solution that worked for that question. I see a lot of these questions as closed and there is no real answer given I will try any solutions available and report results so that others can also solve problems not be overwhelmed by overly broad troubleshooting guides that do nothing to help solve specific issues The nomodeset change from quiet splash also yields no results on reboot I still get a blank screen this screen still has contorl alt f1 abilities but that is it contorl alt f8 causes blinking cursor and F7 gets a crazy flash with green and blue then blank screen Contorl alt f1 a log in prompt in text only when run in recovery mode with failsafe graphics its says the syestem is running in low graphics mode your screen graphics card and input device settings could not be detected correctly. You will need to configure these your self how do i do that? I got this /var/log/failsafeX-backup-120909200641.tar as the location of my log files but i have no idea how to axcess sounds work in blank screen also screen responds or flashes after log in is typed and password entered really any help is good I don't even know where to start I believe 12.04 is installed and functioning but i don't think I can see it at the end of the error log it says error setting mtrr (base= oxf0000000, size= 0x01000000, type=1) inappropriate ioctl for device(25) i have tried to provide as much info as I understand how to provide

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• Preferred way for dealing with customer-defined data in enterprise application

  - by Axarydax

  Let's say that we have a small enterprise web (intranet) application for managing data for car dealers. It has screens for managing customers, inventory, orders, warranties and workshops. This application is installed at 10 customer sites for different car dealers. First version of this application was created without any way to provide for customer-specific data. For example, if dealer A wanted to be able to attach a photo to a customer, dealer B wanted to add e-mail contact to each workshop, and dealer C wanted to attach multiple PDF reports to a warranty, each and every feature like this was added to the application, so all of the customers received everything on new update. However, this will inevitably lead to conflicts as the number of customers grow as their usage patterns are unique, and if, for instance, a specific dealer requested to have an ability to attach (for some reason) a color of inventory item (and be able to search by this color) as a required item, others really wouldn't need this feature, and definitely will not want it to be a required item. Or, one dealer would like to manage e-mail contacts for their employees on a separate screen of the application. I imagine that a solution for this is to use a kind of plugin system, where we would have a core of the application that provides for standard features like customers, inventory, etc, and all of the customer's installed plugins. There would be different kinds of plugins - standalone screens like e-mail contacts for employees, with their own logic, and customer plugin which would extend or decorate inventory items (like photo or color). Inventory (customer,order,...) plugins would require to have installation procedure, hooks for plugging into the item editor, item displayer, item filtering for searching, backup hook and such. Is this the right way to solve this problem?

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• Packaging MATLAB (or, more generally, a large binary, proprietary piece of software)

  - by nfirvine

  I'm trying to package MATLAB for internal distribution, but this could apply to any piece of software with the same architecture. In fact, I'm packaging multiple releases of MATLAB to be installed concurrently. Key things Very large installation size (~4 GB) Composed of a core, and several plugins (toolboxes) Initially, I created a single "source" package (matlab2011b) that builds several .debs (mainly matlab2011b-core and matlab2011b-toolbox-* for each toolbox). The control file is just the standard all: dh $@ There is no Makefile; only copying files. I use a number of debian/*.install files to specify files to copy from a copy of an installation to /usr/lib/. The problem is, every time I build the thing (say, to make a correction to the core package), it recopies every file listed in the *.install file to e.g debian/$packagename/usr/ (the build phase), and then has to bundle that into a .deb file. It takes a long time, on the order of hours, and is doing a lot of extra work. So my questions are: Can you make dh_install do a hardlink copy (like cp -l) to save time? (AFAICT from the man page, no.) Maybe I should just get it to do this in the Makefile? (That's gonna b e big Makefile.) Can you make debuild only rebuild .debs that need rebuilding? Or specify which .debs to rebuild? Is my approach completely stupid? Should I break each of the toolboxes into its own source package too? (I'll have to do some silly templating or something, because there's hundreds of them. :/)

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• New: Online NetBeans 8 Crash Course

  - by Geertjan

  On Twitter today I came across an announcement for a brand new on-line course in NetBeans 8. Since NetBeans 8 has been released during the past few months, the course is really very new. Go here to get there directly: https://www.video2brain.com/de/videotraining/netbeans-ide-8-0-crashkurs Here's the general idea. As you can see, the course is in German. With my basic understanding of German, I've had no problem in following the course. The trainer speaks clearly and slowly and everything is very well structured. The course covers all the basics of NetBeans IDE. From getting set up to using all the key features. The quality of the videos is great and the content is clear and informative. Once you've bought the course, all the lessons are unlocked. As you can see, they're all quite short and there's really a lot of content, didn't all fit into the screenshot: Quite some work must have gone into this. Here's one of the free lessons in the course, to give an idea of what you'll get: https://www.video2brain.com/de/tutorial/texte-internationalisieren This one is also free: https://www.video2brain.com/de/tutorial/eclipse-projekt-importieren I highly recommend this course especially if you're switching, or thinking about switching, from a different IDE and want to get a thorough overview of all the features that NetBeans IDE provides. Everything in the course is done within NetBeans, which means no slides, just code. You get to see the workflow of all the standard tasks and, for these purposes, the course does a really great job.

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