Search Results

Search found 20211 results on 809 pages for 'language implementation'.

Page 236/809 | < Previous Page | 232 233 234 235 236 237 238 239 240 241 242 243  | Next Page >

• Was API hooking done as needed for Stuxnet to work? I don't think so

  - by The Kaykay

  Caveat: I am a political science student and I have tried my level best to understand the technicalities; if I still sound naive please overlook that. In the Symantec report on Stuxnet, the authors say that once the worm infects the 32-bit Windows computer which has a WINCC setup on it, Stuxnet does many things and that it specifically hooks the function CreateFileA(). This function is the route which the worm uses to actually infect the .s7p project files that are used to program the PLCs. ie when the PLC programmer opens a file with .s7p the control transfers to the hooked function CreateFileA_hook() instead of CreateFileA(). Once Stuxnet gains the control it covertly inserts code blocks into the PLC without the programmers knowledge and hides it from his view. However, it should be noted that there is also one more function called CreateFileW() which does the same task as CreateFileA() but both work on different character sets. CreateFileA works with ASCII character set and CreateFileW works with wide characters or Unicode character set. Farsi (the language of the Iranians) is a language that needs unicode character set and not ASCII Characters. I'm assuming that the developers of any famous commercial software (for ex. WinCC) that will be sold in many countries will take 'Localization' and/or 'Internationalization' into consideration while it is being developed in order to make the product fail-safe ie. the software developers would use UNICODE while compiling their code and not just 'ASCII'. Thus, I think that CreateFileW() would have been invoked on a WINCC system in Iran instead of CreateFileA(). Do you agree? My question is: If Stuxnet has hooked only the function CreateFileA() then based on the above assumption there is a significant chance that it did not work at all? I think my doubt will get clarified if: my assumption is proved wrong, or the Symantec report is proved incorrect. Please help me clarify this doubt. Note: I had posted this question on the general stackexchange website and did not get appropriate responses that I was looking for so I'm posting it here.

  Read the article

• Are first-class functions a substitute for the Strategy pattern?

  - by Prog

  The Strategy design pattern is often regarded as a substitute for first-class functions in languages that lack them. So for example say you wanted to pass functionality into an object. In Java you'd have to pass in the object another object which encapsulates the desired behavior. In a language such as Ruby, you'd just pass the functionality itself in the form of an annonymous function. However I was thinking about it and decided that maybe Strategy offers more than a plain annonymous function does. This is because an object can hold state that exists independently of the period when it's method runs. However an annonymous function by itself can only hold state that ceases to exist the moment the function finishes execution. So my question is: when using a language that features first-class functions, would you ever use the Strategy pattern (i.e. encapsulate the functionality you want to pass around in an explicit object), or would you always use an annonymous function? When would you decide to use Strategy when you can use a first-class function?

  Read the article

• Liberate Your Laptops! The Return of Virtual Developer Day

  - by Justin Kestelyn

  Many enterprises are reducing travel, conference, and training budgets for their developers without any change in expectation for the results those developers must deliver. How can you keep up? Well, some months back we offered you a Virtual Developer Day on the subject of building Rich Enterprise Applications, the key piece of which was free access to a cloud development environment for hands-on. Now it's back, new and improved! Join us for a FREE, online, multi-language event series for developers (English version is on July 27) at Oracle Technology Network 's Virtual Developer Day. This unique one-day event provides you the opportunity to: 1. Get trained on Oracle Tuxedo from the comfort of your laptop 2. Get hands-on, locally with Oracle VM VirtualBox or via the Cloud 3. Learn what Python, Ruby, and PHP have to do with Oracle Tuxedo 4. Network online with peers, Oracle Tuxedo architects and developers worldwide 5. Sessions, Labs, and Live Help in LOCAL Languages! Review the agenda details, dates, and language support options. Space is limited, so register for this event now! For information and to register go to: www.oracle.com/goto/otnvdd

  Read the article

• Java Magazine: Java at Sea!

  - by Tori Wieldt

  The September/October issue of Java Magazine is now out, with several great Java stories, including: Java At Sea? Liquid Robotics charts a new course with expert help from Java pioneer James Gosling.?  ?Duke’s Choice AwardsMeet this year’s winners! (The awards will be presented at the JavaOne Sunday night reception at the Taylor Street Cafe.)Looking Ahead to Project LambdaJava Language Architect Brian Goetz on the importance of lambda expressions.JCP Q&A: Ben EvansThe London JUG representative talks about the JCP and the Java community.Java EE Connector Architecture 1.6Adam Bien on deep integration with connector services in a lean way.DataFX: Populate JavaFX Controls with Real-World DataTools to retrieve, parse, and render data in a variety of JavaFX controls. Fix ThisStephen Chin challenges your JavaFX skills. Java Magazine is a bi-monthly online publication. It includes technical articles on the Java language and platform; Java innovations and innovators; JUG and JCP news; Java events; links to online Java communities; and videos and multimedia demos. Subscriptions are free.

  Read the article

• Leveraging Code Across Platforms in Ever Bigger Games

  - by ashes999

  Summary: The same way that I continually build complex engines and libraries within a single platform and technology to allow me to build increasingly bigger and better games, how to continue this when development crosses into different platforms? If I switch platforms, how do I leverage past code and experiences? Games are hard to build. Big games are even harder to build. I've decided that to be able to make big games, I need to start building smaller games, and building up an asset base of code, assets (graphics, sounds), tools, and most importantly, game engines, so that I can eventually get there. One game at a time. Let me give an analogy. To build an MMO 3D RPG, I would approach this by building and releasing small games with increasingly more features. This could entail, for example: A simple 2D game A tile-based game A game with RPG elements (items, equipment, monsters, battle) A full-fledged RPG A 3D RPG The problem now is if I have to change platforms or tools, I don't know how to leverage past code-bases (and experience) to start with a mature product. Right now, I'm writing Silverlight (FlatRedBall) games. Let's say I stick with this for ten years, and then suddenly decide to write a PS6 game, which is in a different programming language entirely. Granted, I have ten years of game-development experience (and correspondingly ten years of professional software development experience from my day job) to back me up. But I would still like some way to transplant that 2D RPG engine into the new programming language, or else leverage it somehow. Is this even possible? What are my options?

  Read the article

• Apress "Pro DLR in .NET 4' - ISBN 978-1-430203066-3 - Initial comments

  - by TATWORTH

  The dynamic language runtime (DLR) is a radical development of Dot Net. In some ways it is like the Laser was 40 years, a solution looking for a problem. At the moment the DLR supports languages such as Iron Ruby and Iron Python, together with dynamic extensions for C# and VB.NET. Where DLR will also score is the ability to write your own Dot Net language for specialist areas. So how does this book fare in introducing the DLR? It is a book that will require careful study and perhaps reading several times before fully understanding the subject. You will need to spend time trying out the sample code. So who would I recommend this book to? I recommend it to C# development teams for their library. I recommend it to individuals who not only know C# but have a good history of learning other computer languages. It is not a book that can just be "dipped into", but will require one or more reads from start to finish. This is no reflection on the skill of the author but of the newness of the material.

  Read the article

• SOA Community Newsletter March 2012

  - by JuergenKress

  Dear SOA partner community member Thank you for your excellent feedback on the brand new Patch Set 5! PS5 is a combined release of all Fusion Middleware components. We recommend you to use this version for all your upcoming projects. We are very keen to know your feedback on PS5. We request you to please send it across to us, especially if your fist customers are in production. Edwin, Roland and Demed from product management published a joint paper Start Small, Grow Fast. Please let us know if you are interested to write a joint paper. Till we meet again! Till we meet again! To read the newsletter please visit http://tinyurl.com/soanewsMarch2012 (OPN Account required) To become a member of the SOA Partner Community please register at http://www.oracle.com/goto/emea/soa (OPN account required) If you need support with your account please contact the Oracle Partner Business Center. Blog Twitter LinkedIn Mix Forum Technorati Tags: SOA Community newsletter,SOA Community,Oracle,OPN,Jürgen Kress,WebLogic 12c,SOA Implementation Assessment,BPM Implementation Assessment,SOA Certification,SOA Specialist,BPM Certification,BPM Specialist,SOA Suite for Healthcare Integration,SOA Community Forum,SOA Specialization

  Read the article

• Using Clojure instead of Python for scalability (multi core) reasons, good idea?

  - by Vandell

  After reading http://clojure.org/rationale and other performance comparisons between Clojure and many languages, I started to think that apart from ease of use, I shouldn't be coding in Python anymore, but in Clojure instead. Actually, I began to fill irresponsisble for not learning clojure seeing it's benefits. Does it make sense? Can't I make really efficient use of all cores using a more imperative language like Python, than a lisp dialect or other functional language? It seems that all the benefits of it come from using immutable data, can't I do just that in Python and have all the benefits? I once started to learn some Common Lisp, read and done almost all exercices from a book I borrowod from my university library (I found it to be pretty good, despite it's low popularity on Amazon). But, after a while, I got myself struggling to much to do some simple things. I think there's somethings that are more imperative in their nature, that makes it difficult to model those thins in a functional way, I guess. The thing is, is Python as powerful as Clojure for building applications that takes advantages of this new multi core future? Note that I don't think that using semaphores, lock mechanisms or other similar concurrency mechanism are good alternatives to Clojure 'automatic' parallelization.

  Read the article

• Learning OO for a C Programmer

  - by Holysmoke

  I've been programming professionally in C, and only C, for around 10 years in a variety of roles. As would be normal to expect, I understand the idioms of the language fairly well and beyond that also some of the design nuances - which APIs to make public, who calls what, who does what, what is supposed to reentrant and so on. I grew up reading 'Writing Solid Code', it's early C edition, not the one based on C++. However, I've never ever programmed in an OO language. Now, I want to migrate to writing applications for iPhone (maybe android), so want to learn to use Objective-C and use it with a degree of competence fitting a professional programmer. How do I wrap my head around the OO stuff? What would be your smallest reading list suggestion to me. Is there a book that carries some sort of relatively real world example OO design Objective-C? Besides, the reading what source code would you recommend me to go through. How to learn OO paradigm using Objective-C?

  Read the article

• Oracle E-Business Suite is Helping to Save Lives at the National Marrow Donor Program

  - by Di Seghposs

  To improve the management of its life-saving operations, the National Marrow Donor Program recently modernized its financial and procurement operations by upgrading to Oracle E-Business Suite 12.1.   As the global leader in bone marrow and umbilical cord blood transplants, the NMDP manages a complex ecosystem of donor, patient, hospital, and biological data. “Maintaining accurate data and having an efficient matching process is essential, particularly as our global database of bone marrow patients grows and donor lists expand,” says Bruce Schmaltz, director of finance/controller. “We rely on the Oracle E-Business Suite to ensure our procurement and financial management processes meet the highest standards, enabling our growing non-profit to work swiftly and efficiently to help improve and save lives.” As the non-profit organization and its registry grew larger, NMDP needed a modern platform to store and integrate its financial information and complicated procurement process. It selected Oracle E-Business Suite for its ability to fit seamlessly into NMDP’s enterprise architecture. NMDP initially implemented Oracle E-Business Suite release 12 by leveraging Oracle Business Accelerators, which are rapid implementation tools and templates that help reduce implementation time and costs. With Oracle Financial Management and Oracle Procurement, NMDP has streamlined back-office processes and integrated its procure-to-pay business processes by leveraging industry leading accounts payable, accounts receivable, and general ledger modules. NMDP is currently rolling out Oracle Hyperion Performance Management applications and plans to implement Oracle Order Management and Oracle Advanced Pricing by the end of 2012. Read more details about NMDP’s modernization efforts.  For more updates on Oracle Financial Management Solutions, view our November 2012 Oracle Information InDepth Financial Management newsletter. Subscribe Now. 

  Read the article

• What should I "forget" when going to Javascript?

  - by ElGringoGrande

  I went from C=64 Basic and assembler to FORTRAN and C to C++ and Java. Professionally I started in Visual Basic for applications then to Visual Basic 4, 5, 6. After that VB.NET AND C# with some Java here and there. I have played with Ruby and Python and found both fun. During each step I never felt like I had to forget what I had learned before. I always felt like I was just learning better and/or slightly different ways of doing things but the difference was not major. The difference was like the difference between American, Australian and British English. (Maybe assembler was Latin and FORTRAN was Spanish.) But now I am using JavaScript to do real, actual work. (Before used it as a "Scripting" language pure a simple.) And I just feel like I have to forget some things to become proficient in it. It feels like some old Egyptian language. What should I forget? Is it just that code organization is different (no real classes so no one class one file)? Or is it something more basic?

  Read the article

• Is implementing an interface defined in a subpackage an anti-pattern?

  - by Michael Kjörling

  Let's say I have the following: package me.my.pkg; public interface Something { /* ... couple of methods go here ... */ } and: package me.my; import me.my.pkg.Something; public class SomeClass implements Something { /* ... implementation of Something goes here ... */ /* ... some more method implementations go here too ... */ } That is, the class implementing an interface lives closer to the package hierarchy root than does the interface it implements but they both belong in the same package hierarchy. The reason for this in the particular case I have in mind is that there is a previously-existing package that groups functionality which the Something interface logically belongs to, and the logical (as in both "the one you'd expect" and "the one where it needs to go given the current architecture") implementation class exists previously and lives one level "up" from the logical placement of the interface. The implementing class does not logically belong anywhere under me.my.pkg. In my particular case, the class in question implements several interfaces, but that feels like it doesn't make any (or at least no significant) difference here. I can't decide if this is an acceptable pattern or not. Is it or is it not, and why?

  Read the article

• Dojo and Separate JavaScript File

  - by Bunch

  For a project I needed to use the ArcGIS API for some mapping. To use this you need to use Dojo but in this case all it really comes down to is adding some require lines and a addOnLoad on your web page. At first everything was working great, the maps rendered and the various layers would populate as needed. Once it was working I started moving the various javascript functions into their own files to keep everything nice and neat. Then the problems started, mainly the map would not show up any more. So that was a pretty big problem. Luckily the fix was pretty simple, just move the dojo.addOnLoad line into it’s own script tag. If I had the dojo.addOnLoad in the same script block as the various require lines it would not work as expected. Works: <script type="text/javascript" language="javascript" src="javascript/test.js" />     <script type="text/javascript">       dojo.require("esri.map");       dojo.require("esri.tasks.locator");       dojo.require("esri.tasks.query");       dojo.require("esri.tasks.geometry");  </script>  <script type="text/javascript">      dojo.addOnLoad(init);  </script> Does not work: <script type="text/javascript" language="javascript" src="javascript/test.js" /> <script type="text/javascript">       dojo.require("esri.map");       dojo.require("esri.tasks.locator");       dojo.require("esri.tasks.query");       dojo.require("esri.tasks.geometry");       dojo.addOnLoad(init); </script> Technorati Tags: JavaScript,Dojo

  Read the article

• Is it considered poor programming to do this with xna components?

  - by Rob

  I created my own Menu System that is event driven. In order to have a loading screen and multithreaded loading to work, I devised this sort of implementation: //Let's check if the game is done loading. if (_game != null) { _gameLoaded = _game.DoneLoading; } //This means the game is loading still, //therefore the loading screen should be active. if (!_gameLoaded && _gameActive) { _gameScreenList[2].UpdateMenu(); } //The loading screen was selected. if (_gameScreenList[2].CurrentState == GameScreen.State.Shown && !_gameActive) { Components.Add(_game = new ParadoxGame(this)); _game.Initialize(); //Initializes the Game so that the loading can begin. _gameActive = true; } In the XNA Game Component that contains the actual game, in the LoadContent method I simply created a new Thread that calls another method ThreadLoad that has all the actual loading. I also have a boolean variable called DoneLoading in the XNA Game Component that is set to true at the end of the ThreadLoad. I am wondering if this is a poor implementation.

  Read the article

• Count function on tree structure (non-binary)

  - by Spevy

  I am implementing a tree Data structure in c# based (largely on Dan Vanderboom's Generic implementation). I am now considering approach on handling a Count property which Dan does not implement. The obvious and easy way would be to use a recursive call which Traverses the tree happily adding up nodes (or iteratively traversing the tree with a Queue and counting nodes if you prefer). It just seems expensive. (I also may want to lazy load some of my nodes down the road). I could maintain a count at the root node. All children would traverse up to and/or hold a reference to the root, and update a internally settable count property on changes. This would push the iteration problem to when ever I want to break off a branch or clear all children below a given node. Generally less expensive, and puts the heavy lifting what I think will be less frequently called functions. Seems a little brute force, and that usually means exception cases I haven't thought of yet, or bugs if you prefer. Does anyone have an example of an implementation which keeps a count for an Unbalanced and/or non-binary tree structure rather than counting on the fly? Don't worry about the lazy load, or language. I am sure I can adjust the example to fit my specific needs. EDIT: I am curious about an example, rather than instructions or discussion. I know this is not technically difficult...

  Read the article

• How to convince a client to switch to a framework *now*; also examples of great, large-scale php applications.

  - by cbrandolino

  Hi everybody. I'm about to start working on a very ambitious project that, in my opinion, has some great potential for what concerns the basic concept and the implementation ideas (implementation as in how this ideas will be implemented, not as in programming). The state of the code right now is unluckily subpar. It's vanilla php, no framework, no separation between application and visualization logic. It's been done mostly by amateur students (I know great amateur/student programmers, don't get me wrong: this was not the case though). The clients are really great, and they know the system won't scale and needs a redesign. The problem is, they would like to launch a beta ASAP and then think of rebuilding. Since just the basic functionalities are present now, I suggested it would be a great idea if we (we're a three-people shop, all very proficient) ported that code to some framework (we like CodeIgniter) before launching. We would reasonably be able to do that in < 10 days. Problem is, they don't think php would be a valid long-term solution anyway, so they would prefer to just let it be and fix the bugs for now (there's quite a bit) and then directly switch to some ruby/python based system. Porting to CI now will make future improvements incredibly easier, the current code more secure, changing the style - still being discussed with the designers - a breeze (reminder: there are database calls in template files right now); the biggest obstacle is the lack of trust in php as a valid, scalable technology. So well, I need some examples of great php applications (apart from facebook) and some suggestions on how to try to convince them to port soon. Again, they're great people - it's not like they would like ruby cause it's so hot right now; they just don't trust php since us cool programmers like bashing it, I suppose, but I'm sure going on like this for even one more day would be a mistake. Also, we have some weight in the decision process.

  Read the article

• How exactly to implement multiple threads in a game

  - by xerwin

  So I recently started learning Java, and having a interest in playing games as well as developing them, naturally I want to create game in Java. I have experience with games in C# and C++ but all of them were single-threaded simple games. But now, I learned how easy it is to make threads in Java, I want to take things to the next level. I started thinking about how would I actually implement threading in a game. I read couple of articles that say the same thing "Usually you have thread for rendering, for updating game logic, for AI, ..." but I haven't (or didn't look hard enough) found example of implementation. My idea how to make implementation is something like this (example for AI) public class AIThread implements Runnable{ private List<AI> ai; private Player player; /*...*/ public void run() { for (int i = 0; i < ai.size(); i++){ ai.get(i).update(player); } Thread.sleep(/* sleep until the next game "tick" */); } } I think this could work. If I also had a rendering and updating thread list of AI in both those threads, since I need to draw the AI and I need to calculate the logic between player and AI(But that could be moved to AIThread, but as an example) . Coming from C++ I'm used to do thing elegantly and efficiently, and this seems like neither of those. So what would be the correct way to handle this? Should I just keep multiple copies of resources in each thread or should I have the resources on one spot, declared with synchronized keyword? I'm afraid that could cause deadlocks, but I'm not yet qualified enough to know when a code will produce deadlock.

  Read the article

• Java Magazine: Growing on Open

  - by Tori Wieldt

  The November/December issue of Java Magazine is now out, with several great Java stories, including: Growing on Open AgroSense provides an all-Java open source platform for sustainable farming and precision agriculture. An Engine for Big Data Hadoop uses Java for large-scale analytics. JavaFX in SpringStephen Chin shows you why to use the Spring framework on the client. JCP Executive Q&A: Mike MilinkovichThe Eclipse Foundation’s executive director assesses the state of Java and the JCP. Exploring Lambda Expressions for the Java Language and the JVMBen Evans, Martijn Verburg, and Trisha Gee help you get ready for lambda expressions in Java SE 8. Get Started with Java SE for Embedded Devices on Raspberry PiWe walk you through getting Linux and Java SE for Embedded Devices to run on the Raspberry Pi in less than an hour. Java NationGet the news from JavaOne 2012 in San Francisco. Java Magazine is a bi-monthly online publication. It includes technical articles on the Java language and platform; Java innovations and innovators; JUG and JCP news; Java events; links to online Java communities; and videos and multimedia demos. Subscriptions are free. Do you have feedback about Java Magazine? Send a tweet to @oraclejavamag.

  Read the article

• CoffeeScript - inability to support progressive adoption

  - by Renso

  First if, what is CoffeeScript?Web definitionsCoffeeScript is a programming language that compiles statement-by-statement to JavaScript. The language adds syntactic sugar inspired by Ruby and Python to enhance JavaScript's brevity and readability, as well as adding more sophisticated features like array comprehension and pattern matching.The issue with CoffeeScript is that it eliminates any progressive adoption. It is a purist approach, kind of like the Amish, if you're not borne Amish, tough luck. So for folks with thousands of lines of JavaScript code will have a tough time to convert it to CoffeeScript. You can use the js2coffee API to convert the JavaScript file to CoffeeScript but in my experience that had trouble converting the files. It would convert the file to CoffeeScript without any complaints, but then when trying to generate the CoffeeScript file got errors with guess what: INDENTATION!Tried to convince the CoffeeScript community on github but got lots of push-back to progressive adoption with comments like "stupid", "crap", "child's comportment", "it's like Ruby, Python", "legacy code" etc. As a matter of interest one of the first comments were that the code needs to be re-designed before converted to CoffeeScript. Well I rest my case then :-)So far the community on github has been very reluctant to even consider introducing some way to define code-blocks, obviously curly braces is not an option as they use it for json object definitions. They also have no consideration for a progressive adoption where some, if not all, JavaScript syntax will be allowed which means all of us in the real world that have thousands of lines of JavaScript will have a real issue converting it over. Worst, I for one lack the confidence that tools like js2coffee will provide the correct indentation that will determine the flow of control in your code!!! Actually it is hard for me to find enough justification for using spaces or tabs to control the flow of code. It is no wonder that C#, C, C++, Java, all enterprise-scale frameworks still use curly braces. Have never seen an enterprise app built with Ruby or PhP.Let me know what your concerns are with CoffeeScript and how you dealt with large scale JavaScript conversions to CoffeeScript.

  Read the article

• Impact on SEO of adding categories/tags in front of the HTML title [closed]

  - by Mad Scientist

  Possible Duplicate: Does the order of keywords matter in a page title? All StackExchange sites add the most-used tag of a question in front of the HTML title for SEO purposes. On Stackoverflow for example this is usually the programming language, so you end up with a title like python - How do I do X? This has obviously an enourmous benefit on SEO as the programming language is an extremely important keyword that is very often omitted from the title. Now, my question is for the cases where the tag isn't an important keyword missing from the title, but just a category. So on Biology.SE for example one would have questions like biochemistry - How does protein X interact with Y? or on Skeptics medical science - Do vaccines cause autism? Those tags are usually not part of the search terms, they serve to categorize the content but users don't use those tags in their searches. How harmful is adding tags that are not used in searches in terms of SEO? Is there any hard data on the impact this practise might have on SEO? The negative aspects I can imagine, but have no data to show that it is actually a problem are: I heard that search engines dislike keyword stuffing and this might trigger some defense mechanisms against that It's a practise associated with less reputable sites, a keyword in front that doesn't fit the actual title well might look suspicious to some users. It wastes precious space in the title shown in search results.

  Read the article

• Using visitor pattern with large object hierarchy

  - by T. Fabre

  Context I've been using with a hierarchy of objects (an expression tree) a "pseudo" visitor pattern (pseudo, as in it does not use double dispatch) : public interface MyInterface { void Accept(SomeClass operationClass); } public class MyImpl : MyInterface { public void Accept(SomeClass operationClass) { operationClass.DoSomething(); operationClass.DoSomethingElse(); // ... and so on ... } } This design was, however questionnable, pretty comfortable since the number of implementations of MyInterface is significant (~50 or more) and I didn't need to add extra operations. Each implementation is unique (it's a different expression or operator), and some are composites (ie, operator nodes that will contain other operator/leaf nodes). Traversal is currently performed by calling the Accept operation on the root node of the tree, which in turns calls Accept on each of its child nodes, which in turn... and so on... But the time has come where I need to add a new operation, such as pretty printing : public class MyImpl : MyInterface { // Property does not come from MyInterface public string SomeProperty { get; set; } public void Accept(SomeClass operationClass) { operationClass.DoSomething(); operationClass.DoSomethingElse(); // ... and so on ... } public void Accept(SomePrettyPrinter printer) { printer.PrettyPrint(this.SomeProperty); } } I basically see two options : Keep the same design, adding a new method for my operation to each derived class, at the expense of maintainibility (not an option, IMHO) Use the "true" Visitor pattern, at the expense of extensibility (not an option, as I expect to have more implementations coming along the way...), with about 50+ overloads of the Visit method, each one matching a specific implementation ? Question Would you recommand using the Visitor pattern ? Is there any other pattern that could help solve this issue ?

  Read the article

• Compressing/compacting messages over websocket on Node.js

  - by icelava

  We have a websocket implementation (Node.js/Sock.js) that exchanges data as JSON strings. As our use cases grow, so have the size of the data transmitted across the wire. The websocket protocol does not natively offer any compression feature, so in order to reduce the size of our messages we'd have to manually do something about the serialisation. There appear to be a variety of LZW implementations in Javascript, some which confuses me on their compatibility for in-browser use only versus transmission across the wire due to my lack of understanding on low-level encodings. More importantly, all of them seem to take a noticeable performance drag when Javascript is the engine doing the compression/decompression work, which is not desirable for mobile devices. Looking instead other forms of compact serialisation, MessagePack does not appear to have any active support in Javascript itself; BSON does not have any Javascript implementation; and an alternative BISON project that I tested does not deserialise everything back to their original values (large numbers), and it does not look like any further development will happen either. What are some other options others have explored for Node.js?

  Read the article

• How should I architect a personal schedule manager that runs 24/7?

  - by Crawford Comeaux

  I've developed an ADHD management system for myself that's attempting to change multiple habits at once. I know this is counter to conventional wisdom, but I've tried the conventional for years & am now trying it my way. (just wanted to say that to try and prevent it from distracting people from the actual question) Anyway, I'd like to write something to run on a remote server that monitors me, helps me build/avoid certain habits, etc. What this amounts to is a system that: runs 24/7 may have multiple independent tasks to run at once may have tasks that require other tasks to run first lets tasks be scheduled by specific time, recurrence (ie. "run every 5 mins"), or interval (ie. "run from 2pm to 3pm") My first naive attempt at this was just a single PHP script scheduled to run every minute by cron (language was chosen in order to use a certain library, but no longer necessary). The logic behind when to run this or that portion of code got hairy pretty quick. So my question is how should I approach this from here? I'm not tied to any one language, though I'm partial to python/javascript. Thoughts: Could be done as a set of scripts that include a scheduling mechanism with one script per bit of logic...but the idea just feels wrong to me. Building it as a daemon could be helpful, but still unsure what to do about dozens of if-else statements for detecting the current time

  Read the article

• Designs for outputting to a spreadsheet

  - by Austin Moore

  I'm working on a project where we are tasked to gather and output various data to a spreadsheet. We are having tons of problems with the file that holds the code to write the spreadsheet. The cell that the data belongs to is hardcoded, so anytime you need to add anything to the middle of the spreadsheet, you have to increment the location for all the fields after that in the code. There are random blank rows, to add padding between sections, and subsections within the sections, so there's no real pattern that we can replicate. Essentially, anytime we have to add or change anything to the spreadsheet it requires a many long and tedious hours. The code is all in this one large file, hacked together overtime in Perl. I've come up with a few OO solutions, but I'm not too familiar with OO programming in Perl and all my attempts at it haven't been great, so I've shied away from it so far. I've suggested we handle this section of the program with a more OO friendly language, but we can't apparently. I've also suggested that we scrap the entire spreadsheet idea, and just move to a webpage, but we can't do that either. We've been working on this project for a few months, and every time we have to change that file, we all dread it. I'm thinking it's time to start some refactoring. However, I don't even know what could make this file easier to work with. The way the output is formatted makes it so that it has to be somewhat hardcoded. I'm wondering if anyone has insight on any design patterns or techniques they have used to tackle a similar problem. I'm open to any ideas. Perl specific answers are welcome, but I am also interested in language-agnostic solutions.

  Read the article

• Thoughts on type aliases/synonyms?

  - by Rei Miyasaka

  I'm going to try my best to frame this question in a way that doesn't result in a language war or list, because I think there could be a good, technical answer to this question. Different languages support type aliases to varying degrees. C# allows type aliases to be declared at the beginning of each code file, and they're valid only throughout that file. Languages like ML/Haskell use type aliases probably as much as they use type definitions. C/C++ are sort of a Wild West, with typedef and #define often being used seemingly interchangeably to alias types. The upsides of type aliasing don't invoke too much dispute: It makes it convenient to define composite types that are described naturally by the language, e.g. type Coordinate = float * float or type String = [Char]. Long names can be shortened: using DSBA = System.Diagnostics.DebuggerStepBoundaryAttribute. In languages like ML or Haskell, where function parameters often don't have names, type aliases provide a semblance of self-documentation. The downside is a bit more iffy: aliases can proliferate, making it difficult to read and understand code or to learn a platform. The Win32 API is a good example, with its DWORD = int and its HINSTANCE = HANDLE = void* and its LPHANDLE = HANDLE FAR* and such. In all of these cases it hardly makes any sense to distinguish between a HANDLE and a void pointer or a DWORD and an integer etc.. Setting aside the philosophical debate of whether a king should give complete freedom to their subjects and let them be responsible for themselves or whether they should have all of their questionable actions intervened, could there be a happy medium that would allow the benefits of type aliasing while mitigating the risk of its abuse? As an example, the issue of long names can be solved by good autocomplete features. Visual Studio 2010 for instance will alllow you to type DSBA in order to refer Intellisense to System.Diagnostics.DebuggerStepBoundaryAttribute. Could there be other features that would provide the other benefits of type aliasing more safely?

  Read the article

< Previous Page | 232 233 234 235 236 237 238 239 240 241 242 243  | Next Page >