Search Results

Search found 17770 results on 711 pages for 'repository design'.

Page 73/711 | < Previous Page | 69 70 71 72 73 74 75 76 77 78 79 80  | Next Page >

• Design a Distributed System

  - by Bonton255

  I am preparing for an interview on Distributed Systems. I have gone through a lot of text and understand the basics of the area. However, I need some examples of discussions on designing a distributed system given a scenario. For example, if I were to design a distributed system to calculate if a number N is primary or not, what will the be design of the system, what will be the impact of network latency, CPU performance, node failure, addition of nodes, time synchronization etc. If you guys could present your in-depth thoughts on this example, or point me to some similar discussion, that would be really helpful.

  Read the article

• Component based design, but components rely on eatchother

  - by MintyAnt

  I've begun stabbing at a "Component Based" game system. Basically, each entity holds a list of components to update (and render) I inherit the "Component" class and break each game system into it. Examples: RenderComponent - Draws the entity MovementComponent - Moves the entity, deals with velocity and speed checks DamageComponent - Deals with how/if the entity gets damaged... So. My system has this: MovementComponent InputComponent Now maybe my design is off, but the InputComponent should say things like if (w key is down) add y speed to movement if (x key is down) Trigger primary attack This means that the InputComponent sort of relies on these other components. I have to do something alone the lines of: if (w key is down) { MovementComponent* entityMovement = mEntity->GetMovement(); if (entityMovement != NULL) add y speed to movement } which seems kinda crappy every update. Other options? Better design? Is this the best way? Thanks!

  Read the article

• in ubuntu 11.10 IDE like dreamweaver for PHP with design mode

  - by pkachhia

  I know that this question is already asked here, but I did not find any free IDE like dreamweaver which have facility to view design mode with PHP+HTML code. I am previously worked on windows machine and used dreamweave, now I moved to ubuntu 11.10 and I need IDE like dreamweaver. Currently I have used Geany and Eclipse but none of them has facility of design mode. Is there any add-on available for Geany or Eclipse then please give it link to me. I am new to ubuntu so, did not have much knowledge of it and because of it I am here for answer. Thanks in advance. Pkachhia

  Read the article

• Design Patterns for SSIS Performance (Presentation)

  Here are the slides from my session (Design patterns for SSIS Performance) presented at SQLBits VI in London last Friday. Slides - Design Patterns for SSIS Performance - Darren Green.pptx (86KB) It was an interesting session, with some very kind feedback, especially considering I woke up on Friday without a voice. The remnants of a near fatal case on man flu rather than any overindulgence the night before I assure you. With much coughing, I tried to turn the off the radio mike during the worst, and an interesting vocal range, we got through it and it seemed to be well received. Thanks to all those who attended.

  Read the article

• Web Design Tips for Search Engine Optimization

  Use these helpful SEO tips to make the design and code of your website more search engine friendly.

  Read the article

• Refactoring to the Template Method Design Pattern

  By Refactoring to established Design Patterns your maintenance efforts will improve rather than degrade the quality of the code.

  Read the article

• Game Object Design

  - by oisin

  I'm having a problem with the way I designed my first simple game in C++. I have GameObject (abstract class) and ObjectA which inherits the update() and draw() methods from GameObject. My main loop contains a linked list of GameObject*, and while that list is not empty it cycles through it, calling update on each one. Up until this point, I thought the design was standard(?) and would work. However, when I call update on ObjectA() I run into two problems: ObjectA can die which messes up the list, which in turn throws off the loop in main. ObjectA can spawn more ObjectA's but these are local scope and the update() goes out of scope, creating problems in main's list of GameObjects. I think my design if alright, but I'm having such problems with segmentation faults that there must be something seriously wrong with at least one part of my implementation. If anyone could point out any serious mistakes or simple examples of this being done (or even alternative designs) then I would greatly appreciate it!

  Read the article

• How do I get yum to see updates to a local repo without cleaning cache?

  - by Matt

  I have set up a local yum repository which I use to install test builds. For the testing purposes, my packages are versioned by <svn version number>.<date>.<time> (e.g. 12345.20110908.150404 The trouble is, once I make a new RPM, copy it to the repository directory and run createrepo $REPO_DIR, yum does not see the new RPM as being available. $ cd $REPO_DIR $ ls -1 repodata package-12345.20110908.150404-1.x86_64.rpm package-12345.20110908.174329-1.x86_64.rpm $ createrepo . # ...snip... $ rpm -q package package-12345.20110908.150404-1.x86_64 $ yum list --showduplicates package Installed Packages package.x86_64 12345.20110908.150404-1 @repo Available Packages package.x86_64 12345.20110908.150404-1 repo I can see the updates and grab them if I run yum clean all and then re-fetch the metadata, but I think this just means I need to be doing something else from the repo, as I don't have to do that for other yum repos. How do I need to set up my local repository so that I only need to run yum update from the client without having to clean my yum cache?

  Read the article

• Database with "Open Schema" - Good or Bad Idea?

  - by Claudiu

  The co-founder of Reddit gave a presentation on issues they had while scaling to millions of users. A summary is available here. What surprised me is point 3: Instead, they keep a Thing Table and a Data Table. Everything in Reddit is a Thing: users, links, comments, subreddits, awards, etc. Things keep common attribute like up/down votes, a type, and creation date. The Data table has three columns: thing id, key, value. There’s a row for every attribute. There’s a row for title, url, author, spam votes, etc. When they add new features they didn’t have to worry about the database anymore. They didn’t have to add new tables for new things or worry about upgrades. This seems like a terrible idea to me, but it seems to have worked out for Reddit. Is it a good idea in general, though? Or is it a peculiarity of Reddit that happened to work out for them?

  Read the article

• Bazaar newbie question about repository structures

  - by esc1729

  I want to use Bazaar on Windows XP for web-development and related tasks. Most of the files are edited locally and then transferred via FTP to the server. Just now the repository sits on my local workstation. Later on it should be shared locally with some co-workers. Perhaps we will use a local Linux server as a centralized repository, but this structure is not decided for now. But first I need to understand the impacts of the different repository setups, which I do not at all. Using Bazaar-Explorer on Windows XP I’ve created a ‘shared tree repository’ from the option list of the init-dialogue in some location dev-filter/. Bazaar Explorer tells me: Created repository with treeless branches at F:/bzr.local/dev-filter Created branch at F:/bzr.local/dev-filter/trunk Created working tree at F:/bzr.local/dev-filter/work OK so far. Now I move a bunch of files into the work directory and add and commit them as Rev 1 ‘Start Revision’. Then I work on some of these files and commit them again as Rev 2. Here my confusion starts. Shouldn’t both revisions go into the trunk? The trunk is still empty, beside the .bzr directory which only holds some management information. If I delete my working directory, which I have tried during these first experiments, everything is gone. There’s obviously no hidden storage of those files. OK. Perhaps I need to push it into the trunk? This does not work either. Entering the work/ directory and initializing the ‘push’ to the trunk, Bazaar-Explorer tells me No new revisions to push. So what? This looks like a severe conceptual misunderstanding about what should happen on my side. Edit, 2010-02-03: Some conclusions What I learned meanwhile is this: I think I should switch to the command line until I really understand what’s going on, at least for creating the repositories and branches. Bazaar Explorer introduces a new level of abstraction which I only can handle if I understand the level beneath One of the secrets of working with Bazaar at least for me is to understand those .bzr directories, their particular properties and states when created with ‘bzr init’, ‘bzr init-repository’, ‘bzr branch’ etc. in all their variants and how they are plumped together. While there’s a whole chapter of ‘Organizing your workspace’ in the Bazaar User Guide, it’s more or less workflow oriented. The manual contains a lot of directory structures for the given examples. What I would prefer beside this and have not (or only rudimentary) found so far is some graphical representation of those ‘Lego like’ .bzr building blocks which create the linking of all the parts. So I started to invent some simple notation while working through the examples and looking into the .bzr directories to document what information is stored there, where does it come from, how and to what is it linked, is it complete or shared, etc. Erich Schreiber

  Read the article

• Parametrized Strategy Pattern

  - by ott

  I have several Java classes which implement the strategy pattern. Each class has variable number parameters of different types: interface Strategy { public data execute(data); } class StrategyA implements Strategy { public data execute(data); } class StrategyB implements Strategy { public StrategyB(int paramA, int paramB); public data execute(data); } class StrategyB implements Strategy { public StrategyB(int paramA, String paramB, double paramC); public data execute(data); } Now I want that the user can enter the parameters in some kind of UI. The UI should be chosen at runtime, i.e. the strategies should be independent of it. The parameter dialog should not be monolithic and there should be the possibility to make it behave and look different for each strategy and UI (e.g. console or Swing). How would you solve this problem?

  Read the article

• Strategy pattern and "action" classes explosion

  - by devoured elysium

  Is it bad policy to have lots of "work" classes(such as Strategy classes), that only do one thing? Let's assume I want to make a Monster class. Instead of just defining everything I want about the monster in one class, I will try to identify what are its main features, so I can define them in interfaces. That will allow to: Seal the class if I want. Later, other users can just create a new class and still have polymorphism by means of the interfaces I've defined. I don't have to worry how people (or myself) might want to change/add features to the base class in the future. All classes inherit from Object and they implement inheritance through interfaces, not from mother classes. Reuse the strategies I'm using with this monster for other members of my game world. Con: This model is rigid. Sometimes we would like to define something that is not easily achieved by just trying to put together this "building blocks". public class AlienMonster : IWalk, IRun, ISwim, IGrowl { IWalkStrategy _walkStrategy; IRunStrategy _runStrategy; ISwimStrategy _swimStrategy; IGrowlStrategy _growlStrategy; public Monster() { _walkStrategy = new FourFootWalkStrategy(); ...etc } public void Walk() { _walkStrategy.Walk(); } ...etc } My idea would be next to make a series of different Strategies that could be used by different monsters. On the other side, some of them could also be used for totally different purposes (i.e., I could have a tank that also "swims"). The only problem I see with this approach is that it could lead to a explosion of pure "method" classes, i.e., Strategy classes that have as only purpose make this or that other action. In the other hand, this kind of "modularity" would allow for high reuse of stratagies, sometimes even in totally different contexts. What is your opinion on this matter? Is this a valid reasoning? Is this over-engineering? Also, assuming we'd make the proper adjustments to the example I gave above, would it be better to define IWalk as: interface IWalk { void Walk(); } or interface IWalk { IWalkStrategy WalkStrategy { get; set; } //or something that ressembles this } being that doing this I wouldn't need to define the methods on Monster itself, I'd just have public getters for IWalkStrategy (this seems to go against the idea that you should encapsulate everything as much as you can!) Why? Thanks

  Read the article

• Factory pattern vs ease-of-use?

  - by Curtis White

  Background, I am extending the ASP.NET Membership with custom classes and extra tables. The ASP.NET MembershipUser has a protected constructor and a public method to read the data from the database. I have extended the database structure with custom tables and associated classes. Instead of using a static method to create a new member, as in the original API: I allow the code to instantiate a simple object and fill the data because there are several entities. Original Pattern #1 Protected constructor > static CreateUser(string mydata, string, mydata, ...) > User.Data = mydata; > User.Update() My Preferred Pattern #2 Public constructor > newUser = new MembershipUser(); > newUser.data = ... > newUser.ComplextObject.Data = ... > newUser.Insert() > newUser.Load(string key) I find pattern #2 to be easier and more natural to use. But method #1 is more atomic and ensured to contain proper data. I'd like to hear any opinions on pros/cons. The problem in my mind is that I prefer a simple CRUD/object but I am, also, trying to utilize the underlying API. These methods do not match completely. For example, the API has methods, like UnlockUser() and a readonly property for the IsLockedOut

  Read the article

• How to store the path of a game pawn in a turn based game ?

  - by panzerschreck

  Hello, I have a square grid, for a turn based game ( grid is similar to the chess board ), but the moves in the games are different based on whether you have lapped your opponent pawn at least once or not. i.e if you have not lapped (beaten any of the opponents pawns) in the outer most grid as below if you have lapped your opponent pawn once at least, then you get to reach home,this way.Any player having all his pawns reaching "home" first wins. The ones in yellow are safe-houses, i.e both the opponent pawn and the player's pawn get to stay in the same grid, this is not considered to be lapping ( the opponent ).The lapped pawn will return to its start point. Now the question is, what is the effective way to store the paths for the all the pawns.we will have 4 pawns for the player and 4 opponent pawns. Is there any pattern to store such static information, in a elegant way ? Thanks for your time

  Read the article

• Concrete Types or Interfaces for return types?

  - by SDReyes

  Today I came to a fundamental paradox of the object programming style, concrete types or interfaces. Whats the better election for a method's return type: a concrete type or an interface? In most cases, I tend to use concrete types as the return type for methods. because I believe that an concrete type is more flexible for further use and exposes more functionality. The dark side of this: Coupling. The angelic one: A concrete type contains per-se the interface you would going to return initially, and extra functionality. What's your thumb's rule? Is there any programming principle for this? BONUS: This is an example of what I mean http://stackoverflow.com/questions/491375/readonlycollection-or-ienumerable-for-exposing-member-collections

  Read the article

• What makes static initialization functions good, bad, or otherwise?

  - by Richard Levasseur

  Suppose you had code like this: _READERS = None _WRITERS = None def Init(num_readers, reader_params, num_writers, writer_params, ...args...): ...logic... _READERS = new ReaderPool(num_readers, reader_params) _WRITERS = new WriterPool(num_writers, writer_params) ...more logic... class Doer: def __init__(...args...): ... def Read(self, ...args...): c = _READERS.get() try: ...work with conn finally: _READERS.put(c) def Writer(...): ...similar to Read()... To me, this is a bad pattern to follow, some cons: Doers can be created without its preconditions being satisfied The code isn't easily testable because ConnPool can't be directly mocked out. Init has to be called right the first time. If its changed so it can be called multiple times, extra logic has to be added to check if variables are already defined, and lots of NULL values have to be passed around to skip re-initializing. In the event of threads, the above becomes more complicated by adding locking Globals aren't being used to communicate state (which isn't strictly bad, but a code smell) On the other hand, some pros: its very convenient to call Init(5, "user/pass", 2, "user/pass") It simple and "clean" Personally, I think the cons outweigh the pros, that is, testability and assured preconditions outweigh simplicity and convenience.

  Read the article

• C#, Linq, Dynamic Query: Code to filter a Dynamic query outside of the Repository

  - by Dr. Zim

  If you do something like this in your Repository: IQueryable<CarClass> GetCars(string condition, params object[] values) { return db.Cars.Where(condition, values); } And you set the condition and values outside of the repository: string condition = "CarMake == @Make"; object[] values = new string[] { Make = "Ford" }; var result = myRepo.GetCars( condition, values); How would you be able to sort the result outside of the repository with Dynamic Query? return View( "myView", result.OrderBy("Price")); Somehow I am losing the DynamicQuery nature when the data exits from the repository. And yes, I haven't worked out how to return the CarClass type where you would normally do a Select new Carclass { fieldName = m.fieldName, ... }

  Read the article

• Is it possible to read from Mercurial repository using PHP

  - by Metropolis

  Hey Everyone, After trying to get the mercurial repository explorer setup on my shared hosting with no luck, I have decided to try and write a module for our Intranet that will act as a repository explorer. Is it possible for me to get changesets from a Mercurial repository without Mercurial installed on the machine? Thanks for any help! Metropolis

  Read the article

• Example with Visitor Pattern

  - by devoured elysium

  public class Song { public string Genre { get; protected set; } public string Name { get; protected set; } public string Band { get; protected set; } public Song(string name, string band, string genre) { Name = name; Genre = genre; Band = band; } } public interface IMusicVisistor { void Visit(List<Song> items); } public class MusicLibrary { List<Song> _songs = new List<Song> { ...songs ... }; public void Accept(IMusicVisitor visitor) { visitor.Visit(_songs); } } and now here's one Visitor I made: public class RockMusicVisitor : IMusicVisitor { public List<Song> Songs { get; protected set; } public void Visit(List<Song> items) { Songs = items.Where(x => x.Genre == "Rock").ToList(); } } Why is this any better than just putting a public property Songs and then letting any kind of class do with it anything that it wants to? This example comes from this post.

  Read the article

• Check to See if File is in Repository with SharpSVN

  - by Jason

  How do I check if a file is already in a repository (or NOT in the repository) so I can determine whether I need to 'add' it first before doing the check in? (For the record, I have check-in working, but I get an exception when I try to check in a file that has not yet been added to the repository.) Thanks

  Read the article

• Creating colour schemes based on an existing scheme

  - by Neil Barnwell

  I have a colour scheme based around yellow, for warning messages on a website. It amounts to a slightly orange bordered box, with a pale yellow fill. The exact colours are: #FED626 (border) #FFF7C0 (fill) I want to know if it's possible to convert this scheme mathematically or algorithmically somehow, to come up with a blue version where the border is the "same amount" of blue as this one is yellow. Is this possible, or do I just "pin the tail on the donkey" on a colour pallet to get roughly the right one? I ask, because I'd quite like to be able to calculate this on the fly, to perhaps implement something in .less. To give you an idea, I tried swopping the red and blue values on those two, and came up with this: #26D6FE (border) #C0F7FF (fill) That wasn't too hard, but think about if I wanted a pink colour scheme... :)

  Read the article

• Seperation of game- and rendering logic

  - by Qua

  What is the best way to seperate rendering code from the actually game engine/logic code? And is it even a good idea to seperate those? Let's assume we have a game object called Knight. The Knight has to be rendered on the screen for the user to see. We're now left with two choices. Either we give the Knight a Render/Draw method that we can call, or we create a renderer class that takes care of rendering all knights. In the scenario where the two is seperated the Knight should the knight still contain all the information needed to render him, or should this be seperated as well? In the last project we created we decided to let all the information required to render an object be stored inside the object itself, but we had a seperate component to actually read those informations and render the objects. The object would contain information such as size, rotation, scale, and which animation was currently playing and based on this the renderer object would compose the screen. Frameworks such as XNA seem to think joining the object and rendering is a good idea, but we're afraid to get tied up to a specific rendering framework, whereas building a seperate rendering component gives us more freedom to change framework at any given time.

  Read the article

• Question regarding factory pattern

  - by eriks

  I have a factory class to build objects of base class B. The object (D) that uses this factory received a list of strings representing the actual types. What is the correct implementation: the factory receives an Enum (and uses switch inside the Create function) and D is responsible to convert the string to Enum. the factory receives a string and checks for a match to a set of valid strings (using ifs') other implementation i didn't think of.

  Read the article

• Empty data problem - data layer or DAL?

  - by luckyluke

  I designing the new App now and giving the following question a lot of thought. I consume a lot of data from the warehouse, and the entities have a lot of dictionary based values (currency, country, tax-whatever data) - dimensions. I cannot be assured though that there won't be nulls. So I am thinking: create an empty value in each of teh dictionaries with special keyID - ie. -1 do the ETL (ssis) do the correct stuff and insert -1 where it needs to let the DAL know that -1 is special (Static const whatever thing) don't care in the code to check for nullness of dictionary entries because THEY will always have a value But maybe I should be thinking: import data AS IS let the DAL do the thinking using empty record Pattern still don't care in the code because business layer will have what it needs from DAL. I think is more of a approach thing but maybe i am missing something important here... What do You think? Am i clear? Please don't confuse it with empty record problem. I do use emptyCustomer think all the time and other defaults too.

  Read the article

• What is the best way to handle validity dates in applications ?

  - by user214626

  Hello, How do we model these objects ? Scenario 1: Price changes in a time period EffectiveDate ExpiryDate Price 2009-01-01 2009-01-31 800$ 2009-02-01 Null 900$ So, if the price changes to 910$ on 2009-02-15, then the system should automatically update the expiry date on the previous effective price to 2009-02-14, to keep it consistent. Scenario 2: No price specified between 2009-02-01 to 2009-02-28 EffectiveDate ExpiryDate Price 2009-01-01 2009-01-31 800$ 2009-03-01 Null 900$ So, if new price is specified for 2009-02-15 onwards , then the system should automatically set the expiry date on the record to be inserted to 2009-02-28, because already a record effective from 2009-03-01 exists. Please suggest an effective way to handle these scenarios to model my framework, or are there any frameworks around that can do this . Thanks

  Read the article

< Previous Page | 69 70 71 72 73 74 75 76 77 78 79 80  | Next Page >