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  • Open a File Browser From Your Current Command Prompt/Terminal Directory

    - by The Geek
    Ever been doing some work at the command line when you realized… it would be a lot easier if I could just use the mouse for this task? One command later, you’ll have a window open to the same place that you’re at. This same tip works in more than one operating system, so we’ll detail how to do it in every way we know how. Open a File Browser in Windows We’ve actually covered this before when we told you how to open an Explorer window from the command prompt’s current directory, but we’ll briefly review: Just type the follow command into your command prompt: explorer . Note: You could actually just type “start .” instead. And you’ll then see a file browsing window set to the same directory you were previous at. And yes, this screenshot is from Vista, but it works the same in every version of Windows. If that wasn’t good enough, you should really read how you can navigate in the File Open/Save dialogs with just the keyboard—now that’s a Stupid Geek Trick! Open a File Browser in Linux For this exercise, we’re going to assume that you’re using Gnome under a Linux flavor like Ubuntu, because that’s the most common. From your terminal window, just type in the following command: nautilus . And the next thing you know, you’ll have a file browser window open at the current location. You’ll see some type of error message at the prompt, but you can pretty much ignore that. You can also use “gnome-open .” if you want. Open Finder in Mac OS X All the Mac computers in this office are running Linux, so we haven’t had a chance to verify, but you should be able to use the following command on OS X to open Finder in the current terminal location: open . Open Dolphin on Linux KDE4 dolphin . Got any extra tips to help out your fellow readers? How do you do the same thing in KDE3? What about OS X? Leave your savvy advice in the comments, and maybe we’ll update the article. Or not. Either way, it’ll help somebody! Similar Articles Productive Geek Tips Keyboard Ninja: Concatenate Multiple Text Files in WindowsStupid Geek Tricks: Open an Explorer Window from the Command Prompt’s Current DirectoryHow to automate FTP uploads from the Windows Command LineShell Geek: Rename Multiple Files At OnceAdd "Open with gedit" to the right click menu in Ubuntu TouchFreeze Alternative in AutoHotkey The Icy Undertow Desktop Windows Home Server – Backup to LAN The Clear & Clean Desktop Use This Bookmarklet to Easily Get Albums Use AutoHotkey to Assign a Hotkey to a Specific Window Latest Software Reviews Tinyhacker Random Tips DVDFab 6 Revo Uninstaller Pro Registry Mechanic 9 for Windows PC Tools Internet Security Suite 2010 Home Networks – How do they look like & the problems they cause Check Your IMAP Mail Offline In Thunderbird Follow Finder Finds You Twitter Users To Follow Combine MP3 Files Easily QuicklyCode Provides Cheatsheets & Other Programming Stuff Download Free MP3s from Amazon

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  • C++ property system interface for game editors (reflection system)

    - by Cristopher Ismael Sosa Abarca
    I have designed an reusable game engine for an project, and their functionality is like this: Is a completely scripted game engine instead of the usual scripting languages as Lua or Python, this uses Runtime-Compiled C++, and an modified version of Cistron (an component-based programming framework).to be compatible with Runtime-Compiled C++ and so on. Using the typical GameObject and Component classes of the Component-based design pattern, is serializable via JSON, BSON or Binary useful for selecting which objects will be loaded the next time. The main problem: We want to use our custom GameObjects and their components properties in our level editor, before used hardcoded functions to access GameObject base class virtual functions from the derived ones, if do you want to modify an property specifically from that class you need inside into the code, this situation happens too with the derived classes of Component class, in little projects there's no problem but for larger projects becomes tedious, lengthy and error-prone. I've researched a lot to find a solution without luck, i tried with the Ogitor's property system (since our engine is Ogre-based) but we find it inappropiate for the component-based design and it's limited only for the Ogre classes and can lead to performance overhead, and we tried some code we find in the Internet we tested it and worked a little but we considered the macro and lambda abuse too horrible take a look (some code omitted): IWE_IMPLEMENT_PROP_BEGIN(CBaseEntity) IWE_PROP_LEVEL_BEGIN("Editor"); IWE_PROP_INT_S("Id", "Internal id", m_nEntID, [](int n) {}, true); IWE_PROP_LEVEL_END(); IWE_PROP_LEVEL_BEGIN("Entity"); IWE_PROP_STRING_S("Mesh", "Mesh used for this entity", m_pModelName, [pInst](const std::string& sModelName) { pInst->m_stackMemUndoType.push(ENT_MEM_MESH); pInst->m_stackMemUndoStr.push(pInst->getModelName()); pInst->setModel(sModelName, false); pInst->saveState(); }, false); IWE_PROP_VECTOR3_S("Position", m_vecPosition, [pInst](float fX, float fY, float fZ) { pInst->m_stackMemUndoType.push(ENT_MEM_POSITION); pInst->m_stackMemUndoVec3.push(pInst->getPosition()); pInst->saveState(); pInst->m_vecPosition.Get()[0] = fX; pInst->m_vecPosition.Get()[1] = fY; pInst->m_vecPosition.Get()[2] = fZ; pInst->setPosition(pInst->m_vecPosition); }, false); IWE_PROP_QUATERNION_S("Orientation (Quat)", m_quatOrientation, [pInst](float fW, float fX, float fY, float fZ) { pInst->m_stackMemUndoType.push(ENT_MEM_ROTATE); pInst->m_stackMemUndoQuat.push(pInst->getOrientation()); pInst->saveState(); pInst->m_quatOrientation.Get()[0] = fW; pInst->m_quatOrientation.Get()[1] = fX; pInst->m_quatOrientation.Get()[2] = fY; pInst->m_quatOrientation.Get()[3] = fZ; pInst->setOrientation(pInst->m_quatOrientation); }, false); IWE_PROP_LEVEL_END(); IWE_IMPLEMENT_PROP_END() We are finding an simplified way to this, without leading confusing the programmers, (will be released to the public) i find ways to achieve this but they are only available for the common scripting as Lua or editors using C#. also too portable, we can write "wrappers" for different GUI toolkits as Qt or GTK, also i'm thinking to using Boost.Wave to get additional macro functionality without creating my own compiler. The properties designed to use in the editor they are removed in the game since the save file contains their data and loads it using an simple 'load' function to reduce unnecessary code bloat may will be useful if some GameObject property wants to be hidden instead. In summary, there's a way to implement an reflection(property) system for a level editor based in properties from derived classes? Also we can use C++11 and Boost (restricted only to Wave and PropertyTree)

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  • Detect Unicode Usage in SQL Column

    One optimization you can make to a SQL table that is overly large is to change from nvarchar (or nchar) to varchar (or char).  Doing so will cut the size used by the data in half, from 2 bytes per character (+ 2 bytes of overhead for varchar) to only 1 byte per character.  However, you will lose the ability to store Unicode characters, such as those used by many non-English alphabets.  If the tables are storing user-input, and your application is or might one day be used internationally, its likely that using Unicode for your characters is a good thing.  However, if instead the data is being generated by your application itself or your development team (such as lookup data), and you can be certain that Unicode character sets are not required, then switching such columns to varchar/char can be an easy improvement to make. Avoid Premature Optimization If you are working with a lookup table that has a small number of rows, and is only ever referenced in the application by its numeric ID column, then you wont see any benefit to using varchar vs. nvarchar.  More generally, for small tables, you wont see any significant benefit.  Thus, if you have a general policy in place to use nvarchar/nchar because it offers more flexibility, do not take this post as a recommendation to go against this policy anywhere you can.  You really only want to act on measurable evidence that suggests that using Unicode is resulting in a problem, and that you wont lose anything by switching to varchar/char. Obviously the main reason to make this change is to reduce the amount of space required by each row.  This in turn affects how many rows SQL Server can page through at a time, and can also impact index size and how much disk I/O is required to respond to queries, etc.  If for example you have a table with 100 million records in it and this table has a column of type nchar(5), this column will use 5 * 2 = 10 bytes per row, and with 100M rows that works out to 10 bytes * 100 million = 1000 MBytes or 1GB.  If it turns out that this column only ever stores ASCII characters, then changing it to char(5) would reduce this to 5*1 = 5 bytes per row, and only 500MB.  Of course, if it turns out that it only ever stores the values true and false then you could go further and replace it with a bit data type which uses only 1 byte per row (100MB  total). Detecting Whether Unicode Is In Use So by now you think that you have a problem and that it might be alleviated by switching some columns from nvarchar/nchar to varchar/char but youre not sure whether youre currently using Unicode in these columns.  By definition, you should only be thinking about this for a column that has a lot of rows in it, since the benefits just arent there for a small table, so you cant just eyeball it and look for any non-ASCII characters.  Instead, you need a query.  Its actually very simple: SELECT DISTINCT(CategoryName)FROM CategoriesWHERE CategoryName <> CONVERT(varchar, CategoryName) Summary Gregg Stark for the tip. Did you know that DotNetSlackers also publishes .net articles written by top known .net Authors? We already have over 80 articles in several categories including Silverlight. Take a look: here.

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  • Working and Studying in Oracle, how I balance my time....

    - by anca.rosu
    Hi, my name is Laura. I am working as an Intern within Executive Administration at Oracle Denmark, whilst studying Information Management at Copenhagen Business school. I have recently handeding a paper on Information Systems which gave me exposure to Oracle. Once completing this paper I came across a job posting on my University’s intranet site and I applied directly online. When I submitted my application for the job offer, I wondered about what language I should use for the application form, as the job posting was in Danish, but the contact person and number looked Irish. I therefore chose English. Later that same day, Fiona, one of Oracle’s Graduates Recruitment Consultants based in Ireland, contacted me. This shows how global Oracle truly is. I went for my face-to-face interview in Oracle Denmark with Charlotte, one of the team managers. I spent 5 minutes waiting in the lobby, just looking around, thinking to myself, I really want to work here. The atmosphere seemed so pleasant with a relaxed approach between colleagues, employees and guests. The interview took about an hour, but we touched on a lot of different subjects. The profile I got of Oraclewas that this is a place where you are encouraged to think for yourself, and you are given the freedom to use your ideas. Later that evening, Fiona called and offered me the job. I was very happy. At Oracle Denmark we have 4 different zones: a Quiet Zone, a Project Zone, a Dialogue Zone and a Call Zone. Everyday when you arrive you consider what will be the most productive for the day’s task, and you take your toolbox and go find a desk in the zone you have decided on. It is therefore very unusual to be next to the same person two days in a row. At Oracle, people are located all over the world, and everybody has team members, colleagues or leaders in other countries, or even other time zones. Initially,I was worried about how I would adapt to this approach but I soon realized I had nothing to worry about and now I appreciate working this way. My colleagues have been very supportive and they have openly welcomed me into my new role. I typically work two days a week and have three days at University. During exam periods, I have the flexibility to work less hours and focus on the exams, in return for putting in more hours at work when needed. The first time I had to ask for time off before handing in a paper, my boss looked at me and said, ”Of course! Your education is the most important!” I hope that by sharing my experiences with you, I can inspire or encourage you to consider Oracle as a potential employer, where you can grow both professionally and personally. If you have any questions related to this article feel free to contact  [email protected].  You can find our job opportunities via http://campus.oracle.com Technorati Tags: Intern,Oracle Denmark,Information Systems,Business school,Copenhagen,Graduates Recruitment,Ireland,Quiet Zone,Project Zone,Dialogue Zone,Call Zone,University,flexibility

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  • How would I handle input with a Game Component?

    - by Aufziehvogel
    I am currently having problems from finding my way into the component-oriented XNA design. I read an overview over the general design pattern and googled a lot of XNA examples. However, they seem to be right on the opposite site. In the general design pattern, an object (my current player) is passed to InputComponent::update(Player). This means the class will know what to do and how this will affect the game (e.g. move person vs. scroll text in a menu). Yet, in XNA GameComponent::update(GameTime) is called automatically without a reference to the current player. The only XNA examples I found built some sort of higher-level Keyboard engine into the game component like this: class InputComponent: GameComponent { public void keyReleased(Keys); public void keyPressed(Keys); public bool keyDown(Keys); public void override update(GameTime gameTime) { // compare previous state with current state and // determine if released, pressed, down or nothing } } Some others went a bit further making it possible to use a Service Locator by a design like this: interface IInputComponent { public void downwardsMovement(Keys); public void upwardsMovement(Keys); public bool pausedGame(Keys); // determine which keys pressed and what that means // can be done for different inputs in different implementations public void override update(GameTime); } Yet, then I am wondering if it is possible to design an input class to resolve all possible situations. Like in a menu a mouse click can mean "click that button", but in game play it can mean "shoot that weapon". So if I am using such a modular design with game components for input, how much logic is to be put into the InputComponent / KeyboardComponent / GamepadComponent and where is the rest handled? What I had in mind, when I heard about Game Components and Service Locator in XNA was something like this: use Game Components to run the InputHandler automatically in the loop use Service Locator to be able to switch input at runtime (i.e. let player choose if he wants to use a gamepad or a keyboard; or which shall be player 1 and which player 2). However, now I cannot see how this can be done. First code example does not seem flexible enough, as on a game pad you could require some combination of buttons for something that is possible on keyboard with only one button or with the mouse) The second code example seems really hard to implement, because the InputComponent has to know in which context we are currently. Moreover, you could imagine your application to be multi-layered and let the key-stroke go through all layers to the bottom-layer which requires a different behaviour than the InputComponent would have guessed from the top-layer. The general design pattern with passing the Player to update() does not have a representation in XNA and I also cannot see how and where to decide which class should be passed to update(). At most time of course the player, but sometimes there could be menu items you have to or can click I see that the question in general is already dealt with here, but probably from a more elobate point-of-view. At least, I am not smart enough in game development to understand it. I am searching for a rather code-based example directly for XNA. And the answer there leaves (a noob like) me still alone in how the object that should receive the detected event is chosen. Like if I have a key-up event, should it go to the text box or to the player?

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  • How the SPARC T4 Processor Optimizes Throughput Capacity: A Case Study

    - by Ruud
    This white paper demonstrates the architected latency hiding features of Oracle’s UltraSPARC T2+ and SPARC T4 processors That is the first sentence from this technical white paper, but what does it exactly mean? Let's consider a very simple example, the computation of a = b + c. This boils down to the following (pseudo-assembler) instructions that need to be executed: load @b, r1 load @c, r2 add r1,r2,r3 store r3, @a The first two instructions load variables b and c from an address in memory (here symbolized by @b and @c respectively). These values go into registers r1 and r2. The third instruction adds the values in r1 and r2. The result goes into register r3. The fourth instruction stores the contents of r3 into the memory address symbolized by @a. If we're lucky, both b and c are in a nearby cache and the load instructions only take a few processor cycles to execute. That is the good case, but what if b or c, or both, have to come from very far away? Perhaps both of them are in the main memory and then it easily takes hundreds of cycles for the values to arrive in the registers. Meanwhile the processor is doing nothing and simply waits for the data to arrive. Actually, it does something. It burns cycles while waiting. That is a waste of time and energy. Why not use these cycles to execute instructions from another application or thread in case of a parallel program? That is exactly what latency hiding on the SPARC T-Series processors does. It is a hardware feature totally transparent to the user and application. As soon as there is a delay in the execution, the hardware uses these otherwise idle cycles to execute instructions from another process. As a result, the throughput capacity of the system improves because idle cycles are no longer wasted and therefore more jobs can be run per unit of time. This feature has been in the SPARC T-series from the beginning, so why this paper? The difference with previous publications on this topic is in the amount of detail given. How this all works under the hood is fully explained using two example programs. Starting from the assembly language instructions, it is demonstrated in what way these programs execute. To really see what is happening we go down to the processor pipeline level, where the gaps in the execution are, and show in what way these idle cycles are filled by other copies of the same program running simultaneously. Both the SPARC T4 as well as the older UltraSPARC T2+ processor are covered. You may wonder why the UltraSPARC T2+ is included. The focus of this work is on the SPARC T4 processor, but to explain the basic concept of latency hiding at this very low level, we start with the UltraSPARC T2+ processor because it is architecturally a much simpler design. From the single issue, in-order pipelines of this processor we then shift gears and cover how this all works on the much more advanced dual issue, out-of-order architecture of the T4. The analysis and performance experiments have been conducted on both processors. The results depend on the processor, but in all cases the theoretical estimates are confirmed by the experiments. If you're interested to read a lot more about this and find out how things really work under the hood, you can download a copy of the paper here. A paper like this could not have been produced without the help of several other people. I want to thank the co-author of this paper, Jared Smolens, for his very valuable contributions and our highly inspiring discussions. I'm also indebted to Thomas Nau (Ulm University, Germany), Shane Sigler and Mark Woodyard (both at Oracle) for their feedback on earlier versions of this paper. Karen Perkins (Perkins Technical Writing and Editing) and Rick Ramsey at Oracle were very helpful in providing editorial and publishing assistance.

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  • what differs a computer scientist/software engineer to regular people who learn programming language and APIs?

    - by Amumu
    In University, we learn and reinvent the wheel a lot to truly learn the programming concepts. For example, we may learn assembly language to understand, what happens inside the box, and how the system operates, when we execute our code. This helps understanding higher level concepts deeper. For example, memory management like in C is just an abstraction of manually managed memory contents and addresses. The problem is, when we're going to work, usually productivity is required more. I could program my own containers, or string class, or date/time (using POSIX with C system call) to do the job, but then, it would take much longer time to use existing STL or Boost library, which abstract all of those thing and very easy to use. This leads to an issue, that a regular person doesn't need to get through all the low level/under the hood stuffs, who learns only one programming language and using language-related APIs. These people may eventually compete with the mainstream graduates from computer science or software engineer and call themselves programmers. At first, I don't think it's valid to call them programmers. I used to think, a real programmer needs to understand the computer deeply (but not at the electronic level). But then I changed my mind. After all, they get the job done and satisfy all the test criteria (logic, performance, security...), and in business environment, who cares if you're an expert and understand how computer works or not. You may get behind the "amateurs" if you spend to much time learning about how things work inside. It is totally valid for those people to call themselves programmers. This makes me confuse. So, after all, programming should be considered an universal skill? Does programming language and concepts matter or the problems we solve matter? For example, many C/C++ vs Java and other high level language, one of the main reason is because C/C++ features performance, as well as accessing low level facility. One of the main reason (in my opinion), is coding in C/C++ seems complex, so people feel good about it (not trolling anyone, just my observation, and my experience as well. Try to google "C hacker syndrome"). While Java on the other hand, made for simplifying programming tasks to help developers concentrate on solving their problems. Based on Java rationale, if the programing language keeps evolve, one day everyone can map their logic directly with natural language. Everyone can program. On that day, maybe real programmers are mathematicians, who could perform most complex logic (including business logic and academic logic) without worrying about installing/configuring compiler, IDEs? What's our job as a computer scientist/software engineer? To solve computer specific problems or to solve problems in general? For example, take a look at this exame: http://cm.baylor.edu/ICPCWiki/attach/Problem%20Resources/2010WorldFinalProblemSet.pdf . The example requires only basic knowledge about the programming language, but focus more on problem solving with the language. In sum, what differs a computer scientist/software engineer to regular people who learn programming language and APIs? A mathematician can be considered a programmer, if he is good enough to use programming language to implement his formula. Can we programmer do this? Probably not for most of us, since we specialize about computer, not math. An electronic engineer, who learns how to use C to program for his devices, can be considered a programmer. If the programming languages keep being simplified, may one day the software engineers, who implements business logic and create softwares, be obsolete? (Not for computer scientist though, since many of the CS topics are scientific, and science won't change, but technology will).

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  • Attending a Career Fair: &ldquo;Don&rsquo;t be shy &ndash; Be prepared&rdquo;

    - by jessica.ebbelaar
    There are a large number of ways to interact with companies nowadays. The career fair is a very effective and personal way to interact with a number of different companies in a very short period of time. Here are some simple tips to help you perform during a career fair. Do research The key to being successful at a career fair is to do research before you go. Make a first selection of the companies you feel could be interesting for you. Include many types of employers. Once you have decided on the list of companies you want to visit, go to their career portal. Inform yourself about what the company does, i.e what roles there are available, how the company culture is described, what impression the testimonials give you. The question that you still have after reviewing this information, are the ones you can discuss with the company on the fair. Sell yourself Visit the companies you have on your top 5 list first, so you will be at your highest energy level to make that first impression. Think in advance about what you are going to tell the recruiter. Prepare a 30-second introduction (including degree, strengths, skills & experience) Be confident when you talk about your experience. Remember to start the conversation with a smile, make good eye contact and give a firm handshake. You could be speaking to your next manager, so be professional! If you already know what jobs you are interested in, relate your skills and experience to the roles that the company has available. If you are not yet sure gather as much information as you can about employment and/or hiring procedures, specific skills necessary for different jobs, training and career paths. Stand out As career fairs are very crowded and the attending companies meet with a lot of potential candidates on one day, you have to make sure you are noticed in a positive way. A good preparation and asking questions that show you have a good understanding of the industry, organization and roles will help you. Be aware of time demands on employers. Do not monopolize an employer's time. Dress appropriately to make a good first impression. Bring your resume Do not forget to bring your resume in print or on a USB-stick to the fair. If you are searching for different types of jobs, bring different versions of your resume. Your resume should be short and professional on white paper that is free of graphics or fancy print styles and containing larger margins for interviewer notes. Follow up After each conversation ask who you can contact for follow-up discussions about the specific roles. Use the back of a business card to record notes that help you remember important details and follow-up instructions. If no card is available, record the contact information and your comments in your notepad or phone. Last but not least, thank everyone you talk to for their time. Follow up as soon as possible with thank you notes that address the companies’ hiring needs, your qualifications, and express your desire for a second interview. What not to do… Do not visit a company with a group of friends. Interact with the companies on your own, to make your own positive impression. Do not walk up to a recruiter and interrupt a current conversation; wait your turn and be polite. What you should absolutely avoid is a grab and run on freebies! Take the time to speak to the company and ask for a freebie at the end of the conversation in case they are not offered to you. Good luck with the preparations for the career fair you will attend. Oracle recruiters look forward to meet you! They will be present on a large number of fairs in the region. For an overview of the fairs go to the Events & Calendar page on http://campus.oracle.com If you have any questions related to this article feel free to contact [email protected].

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  • What is the best practice, point of view of well experienced developers

    - by Damien MIRAS
    My manager pushes me to use his self defined best practices. All of these practices are based on is own assumptions. I disagree with them and I would like to have some feedback of well experienced people about these practices. I would prefer answers from people involved in the maintenance of huge products and people whom have maintained the product for years. Developers with 15+ years of experience are preferred because my manager has that much experience himself. I have 7 years of experience. Here are the practices he wants me to use: never extends classes, use composition and interface instead because extending classes are unmaintainable and difficult to debug. What I think about that Extend when needed, respect "Liskov's Substitution Principle" and you'll never be stuck with a problem, but prefer composition and decoration. I don't know any serious project which has banned inheriting, sometimes it's impossible to not use that, i.e. in a UI framework. Design patterns are just unusable. In PHP, for simple use cases (for example a user needs a web interface to view a database table), his "best practice" is: copy some random php code wich we own, paste and modify it, put html and php code in same file, never use classes in PHP, it doesn't work well for small jobs, and in fact it doesn't work well at all, there is no good tool to work with. Copy & paste PHP code is good practice for maintenance because scripts are independent, if you have a bug somewhere you can fix it without side effects. What I think about that: NEVER EVER COPY code or do it because you have five minutes to deliver something, you will do some refactoring after that. Copy & paste code is a beginners error, if you have errors you'll have the error everywhere any time you have pasted it's a nightmare to maintain. If you repsect the "Open Close Principle" you'll rarely get edge effects, use unit test if you are afraid of that. For small jobs in PHP use at least something you get or write the HTML separately from the PHP code and reuse it any time you need it. Classes in PHP are mature, not as mature as other languages like python or java, but they are usable. There is tools to work with classes in PHP like Zend Studio that work very well. The use of classes or not depends not on the language you use but the programming paradigm you have choosen. I'm a OOP developer, I use PHP5, why do I have to shoot myself in the foot? When you find a simple bug in the code, and you can fix it simply, if you are not working on the code where you have found it, never fix it, even if it takes 5 seconds. He says to me his "best practices" are driven by the fact that he has a lot of experience in maintaining software in production (14 years) and he now knows what works and what doesn't work, what the community says is a fad, and the people advocating such principles as never copy & paste code, are not evolved in maintaining applications. What I think about that: If you find a bug fix it if you can do it quickly inform the people who've touched that code before, check if you have not introduced a new bug, ideally add a unit test for it. I currently work on a web commerce project, which serves 15k unique users per day. The code base has to be maintained and has been maintained this way since 2005. Ideally you include a short description of your position and experience in terms of years effectively maintaining an application which has been in production for real.

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  • Why Is Hibernation Still Used?

    - by Jason Fitzpatrick
    With the increased prevalence of fast solid-state hard drives, why do we still have system hibernation? Today’s Question & Answer session comes to us courtesy of SuperUser—a subdivision of Stack Exchange, a community-driven grouping of Q&A web sites. The Question SuperUser reader Moses wants to know why he should use hibernate on a desktop machine: I’ve never quite understood the original purpose of the Hibernation power state in Windows. I understand how it works, what processes take place, and what happens when you boot back up from Hibernate, but I’ve never truly understood why it’s used. With today’s technology, most notably with SSDs, RAM and CPUs becoming faster and faster, a cold boot on a clean/efficient Windows installation can be pretty fast (for some people, mere seconds from pushing the power button). Standby is even faster, sometimes instantaneous. Even SATA drives from 5-6 years ago can accomplish these fast boot times. Hibernation seems pointless to me [on desktop computers] when modern technology is considered, but perhaps there are applications that I’m not considering. What was the original purpose behind hibernation, and why do people still use it? Quite a few people use hibernate, so what is Moses missing in the big picture? The Answer SuperUser contributor Vignesh4304 writes: Normally hibernate mode saves your computer’s memory, this includes for example open documents and running applications, to your hard disk and shuts down the computer, it uses zero power. Once the computer is powered back on, it will resume everything where you left off. You can use this mode if you won’t be using the laptop/desktop for an extended period of time, and you don’t want to close your documents. Simple Usage And Purpose: Save electric power and resuming of documents. In simple terms this comment serves nice e.g (i.e. you will sleep but your memories are still present). Why it’s used: Let me describe one sample scenario. Imagine your battery is low on power in your laptop, and you are working on important projects on your machine. You can switch to hibernate mode – it will result your documents being saved, and when you power on, the actual state of application gets restored. Its main usage is like an emergency shutdown with an auto-resume of your documents. MagicAndre1981 highlights the reason we use hibernate everyday: Because it saves the status of all running programs. I leave all my programs open and can resume working the next day very easily. Doing a real boot would require to start all programs again, load all the same files into those programs, get to the same place that I was at before, and put all my windows in exactly the same place. Hibernating saves a lot of work pulling these things back up again. It’s not unusual to find computers around the office here that have been hibernated day in and day out for months without an actual full system shutdown and restart. It’s enormously convenient to freeze your work space at the exact moment you stopped working and to turn right around and resume there the next morning. Have something to add to the explanation? Sound off in the the comments. Want to read more answers from other tech-savvy Stack Exchange users? Check out the full discussion thread here.     

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  • Talking JavaOne with Rock Star Kirk Pepperdine

    - by Janice J. Heiss
    Kirk Pepperdine is not only a JavaOne Rock Star but a Java Champion and a highly regarded expert in Java performance tuning who works as a consultant, educator, and author. He is the principal consultant at Kodewerk Ltd. He speaks frequently at conferences and co-authored the Ant Developer's Handbook. In the rapidly shifting world of information technology, Pepperdine, as much as anyone, keeps up with what's happening with Java performance tuning. Pepperdine will participate in the following sessions: CON5405 - Are Your Garbage Collection Logs Speaking to You? BOF6540 - Java Champions and JUG Leaders Meet Oracle Executives (with Jeff Genender, Mattias Karlsson, Henrik Stahl, Georges Saab) HOL6500 - Finding and Solving Java Deadlocks (with Heinz Kabutz, Ellen Kraffmiller Martijn Verburg, Jeff Genender, and Henri Tremblay) I asked him what technological changes need to be taken into account in performance tuning. “The volume of data we're dealing with just seems to be getting bigger and bigger all the time,” observed Pepperdine. “A couple of years ago you'd never think of needing a heap that was 64g, but today there are deployments where the heap has grown to 256g and tomorrow there are plans for heaps that are even larger. Dealing with all that data simply requires more horse power and some very specialized techniques. In some cases, teams are trying to push hardware to the breaking point. Under those conditions, you need to be very clever just to get things to work -- let alone to get them to be fast. We are very quickly moving from a world where everything happens in a transaction to one where if you were to even consider using a transaction, you've lost." When asked about the greatest misconceptions about performance tuning that he currently encounters, he said, “If you have a performance problem, you should start looking at code at the very least and for that extra step, whip out an execution profiler. I'm not going to say that I never use execution profilers or look at code. What I will say is that execution profilers are effective for a small subset of performance problems and code is literally the last thing you should look at.And what is the most exciting thing happening in the world of Java today? “Interesting question because so many people would say that nothing exciting is happening in Java. Some might be disappointed that a few features have slipped in terms of scheduling. But I'd disagree with the first group and I'm not so concerned about the slippage because I still see a lot of exciting things happening. First, lambda will finally be with us and with lambda will come better ways.” For JavaOne, he is proctoring for Heinz Kabutz's lab. “I'm actually looking forward to that more than I am to my own talk,” he remarked. “Heinz will be the third non-Sun/Oracle employee to present a lab and the first since Oracle began hosting JavaOne. He's got a great message. He's spent a ton of time making sure things are going to work, and we've got a great team of proctors to help out. After that, getting my talk done, the Java Champion's panel session and then kicking back and just meeting up and talking to some Java heads."Finally, what should Java developers know that they currently do not know? “’Write Once, Run Everywhere’ is a great slogan and Java has come closer to that dream than any other technology stack that I've used. That said, different hardware bits work differently and as hard as we try, the JVM can't hide all the differences. Plus, if we are to get good performance we need to work with our hardware and not against it. All this implies that Java developers need to know more about the hardware they are deploying to.”

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  • Big Data – ClustrixDB – Extreme Scale SQL Database with Real-time Analytics, Releases Software Download – NewSQL

    - by Pinal Dave
    There are so many things to learn and there is so little time we all have. As we have little time we need to be selective to learn whatever we learn. I believe I know quite a lot of things in SQL but I still do not know what is around SQL. I have started to learn about NewSQL recently. If you wonder what is NewSQL I encourage all of you to read my blog post about NewSQL over here Big Data – Buzz Words: What is NewSQL – Day 10 of 21. NewSQL databases are quickly becoming popular – providing the scale of NoSQL with the SQL features and transactions. As a part of learning NewSQL database, I have recently started to learn about ClustrixDB. ClustrixDB has been the most mature NewSQL database used by some of the largest internet sites in the world for over 3 years, with extensive SQL support. In addition to scale, it provides fast real-time analytics by bringing massively parallel processing (MPP), available only in warehousing databases, to the transactional database. The reason I am more intrigued about learning ClustrixDB is their recent announcement on Oct 31. ClustrixDB was only available as an appliance, but now with their software release on Oct 31, everyone can use it. It is now available as forever free for up to 12 cores with community support, and there is a 45 day trial for unlimited cluster sizes. With the forever free world, I am indeed interested in ClustrixDB now. I know that few of the leading eCommerce sites in the world uses them for their transactional database. Here are few of the details I have quickly noted for ClustrixDB. ClustrixDB allows user to: Scale by simply adding nodes to the cluster with a single command Run billions of transactions a day Run fast real-time analytics Achieve high-availability with recovery from node failure Manages itself Easily migrate from MySQL as it is nearly plug-and-play compatible, use MySQL drivers, tools and replication. While I was going through the documentation I realized that ClustrixDB also has extensive support for SQL features including complex queries involving joins on a dozen or more tables, aggregates, sorts, sub-queries. It also supports stored procedures, triggers, foreign keys, partitioned and temporary tables, and fully online schema changes. It is indeed a very matured product and SQL solution. Indeed Clusterix sound very promising solution, I decided to dig a bit deeper to understand who are current customers of the Clustrix as they exist in the industry for quite a few years. Their client list is indeed very interesting and here is my quick research about them. Twoo.com – Europe’s largest social discovery (dating) site runs 4.4 Billion Transactions a day with table sizes over a Terabyte, on a 168 core cluster. EngageBDR – Top 3 in the online advertising category uses ClustrixDB to serve 6.9 billion ads a day through real-time bidding platform. Their reports went from 4 hours to 15 seconds. NoMoreRack – Top 2 fastest growing e-commerce company in US used ClustrixDB for high availability and fast growth through Amazon cloud. MakeMyTrip – India’s leading travel site runs on ClustrixDB with two clusters running as multi-master in Chennai and Bangalore. Many enterprises such as AOL, CSC, Rakuten, Symantec use ClustrixDB when their applications need scale. I must accept that I am impressed with the information I have learned so far and now is the time to do some hand’s on experience with their product. I want to learn this technology so in future when it is about NewSQL, I know what I am talking about. Read more why Clustrix explains why you ClustrixDB might be the right database for you. Download ClustrixDB with me today and install it on your machine so in future when we discuss the technical aspects of it, we all are on the same page. The software can be downloaded here. Reference : Pinal Dave (http://blog.SQLAuthority.com)Filed under: Big Data, MySQL, PostADay, SQL, SQL Authority, SQL Query, SQL Server, SQL Tips and Tricks, T SQL Tagged: Clustrix

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  • Projet Doneness and Einstein's Razor

    - by Malcolm Anderson
    Normal 0 false false false EN-US X-NONE X-NONE MicrosoftInternetExplorer4 /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-qformat:yes; mso-style-parent:""; mso-padding-alt:0in 5.4pt 0in 5.4pt; mso-para-margin-top:0in; mso-para-margin-right:0in; mso-para-margin-bottom:10.0pt; mso-para-margin-left:0in; line-height:115%; mso-pagination:widow-orphan; font-size:11.0pt; font-family:"Calibri","sans-serif"; mso-ascii-font-family:Calibri; mso-ascii-theme-font:minor-latin; mso-fareast-font-family:"Times New Roman"; mso-fareast-theme-font:minor-fareast; mso-hansi-font-family:Calibri; mso-hansi-theme-font:minor-latin;} I’ve started working on a series of articles about the value of having testers involved in requirements gathering.  Today I was reminded of a useful tool that has provided value to me for at least 20 years.  To those of you who already use this tool, I’m interested in your stories where it has made a difference for you, and to those of you who have never heard of it, I hope sharing it will make a difference in your careers.   I was reminded of it because I just finished a 3 month set of personal projects and was reviewing the success of those projects while putting together my next set of 3 month projects.  During this review, I noticed that a good number of my projects did not have the level of success that I wanted.  The results were good, but they could have been better.  Then it hit me, I didn’t have clear enough doneness criteria.  As a Scrum Practitioner, I wouldn’t think of running a sprint without reviewing the backlog with Einstein's Razor, so why wouldn’t I do the same for my own projects?    I can hear a few of you asking "What's Einstein's Razor?"   I'm glad you asked.  I was once told that Einstein told an audience, "If you can't explain what you do to a relatively bright six year old, you probably don't understand it yourself."    This quote had an impact on me, especially early in my career as a solo developer.  At the time, I was mostly doing end to end software development.  I found that I saved myself a lot of pain and trouble by turning that quote around to “If you can't explain your project's doneness criteria in such a way that a relatively bright six year old can't competently determine your projects success or failure, then you have not broken it down to a fine enough level.”  There are more negatives in that quote than I’m happy with, but it still gives me tons of value to this day.     In your opinion, in your current projects, could a 6 year old competently pass or fail your next sprint?  What risks are you running if your answer is “No” ?

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  • Where to store front-end data for "object calculator"

    - by Justin Grahn
    I recently have completed a language library that acts as a giant filter for food items, and flows a bit like this :Products -> Recipes -> MenuItems -> Meals and finally, upon submission, creates an Order. I have also completed a database structure that stores all the pertinent information to each class, and seems to fit my needs. The issue I'm having is linking the two. I imagined all of the information being local to each instance of the product, where there exists one backend user who edits and manipulates data, and multiple front end users who select their Meal(s) to create an Order. Ideally, all of the front end users would have all of this information stored locally within the library, and would update the library on startup from a database. How should I go about storing the data so that I can load it into the library every time the user opens the application? Do I package a database onboard and just load and populate every time? The only method I can currently conceive of doing this, even if I only have 500 possible Product objects, would require me to foreach the list for every Product that I need to match to a Recipe and so on and so forth every time I relaunch the program, which seems like a lot of wasteful loading. Here is a general flow of my architecture: Products: public class Product : IPortionable { public Product(string n, uint pNumber = 0) { name = n; productNumber = pNumber; } public string name { get; set; } public uint productNumber { get; set; } } Recipes: public Recipe(string n, decimal yieldAmt, Volume.Unit unit) { name = n; yield = new Volume(yieldAmt, unit); yield.ConvertUnit(); } /// <summary> /// Creates a new ingredient object /// </summary> /// <param name="n">Name</param> /// <param name="yieldAmt">Recipe Yield</param> /// <param name="unit">Unit of Yield</param> public Recipe(string n, decimal yieldAmt, Weight.Unit unit) { name = n; yield = new Weight(yieldAmt, unit); } public Recipe(Recipe r) { name = r.name; yield = r.yield; ingredients = r.ingredients; } public string name { get; set; } public IMeasure yield; public Dictionary<IPortionable, IMeasure> ingredients = new Dictionary<IPortionable,IMeasure>(); MenuItems: public abstract class MenuItem : IScalable { public static string title = null; public string name { get; set; } public decimal maxPortionSize { get; set; } public decimal minPortionSize { get; set; } public Dictionary<IPortionable, IMeasure> ingredients = new Dictionary<IPortionable, IMeasure>(); and Meal: public class Meal { public Meal(int guests) { guestCount = guests; } public int guestCount { get; private set; } //TODO: Make a new MainCourse class that holds pasta and Entree public Dictionary<string, int> counts = new Dictionary<string, int>(){ {MainCourse.title, 0}, {Side.title , 0}, {Appetizer.title, 0} }; public List<MenuItem> items = new List<MenuItem>(); The Database just stores and links each of these basic names and amounts together usings ID's (RecipeID, ProductID and MenuItemID)

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  • Cloud hosted CI for .NET projects

    - by Scott Dorman
    Originally posted on: http://geekswithblogs.net/sdorman/archive/2014/06/02/cloud-hosted-ci-for-.net-projects.aspxContinuous integration (CI) is important. If you don’t have it set up…you should. There are a lot of different options available for hosting your own CI server, but they all require you to maintain your own infrastructure. If you’re a business, that generally isn’t a problem. However, if you have some open source projects hosted, for example on GitHub, there haven’t really been any options. That has changed with the latest release of AppVeyor, which bills itself as “Continuous integration for busy developers.” What’s different about AppVeyor is that it’s a hosted solution. Why is that important? By being a hosted solution, it means that I don’t have to maintain my own infrastructure for a build server. How does that help if you’re hosting an open source project? AppVeyor has a really competitive pricing plan. For an unlimited amount of public repositories, it’s free. That gives you a cloud hosted CI system for all of your GitHub projects for the cost of some time to set them up, which actually isn’t hard to do at all. I have several open source projects (hosted at https://github.com/scottdorman), so I signed up using my GitHub credentials. AppVeyor fully supported my two-factor authentication with GitHub, so I never once had to enter my password for GitHub into AppVeyor. Once it was done, I authorized GitHub and it instantly found all of the repositories I have (both the ones I created and the ones I cloned from elsewhere). You can even add “build badges” to your markdown files in GitHub, so anyone who visits your project can see the status of the lasted build. Out of the box, you can simply select a repository, add the build project, click New Build and wait for the build to complete. You now have a complete CI server running for your project. The best part of this, besides the fact that it “just worked” with almost zero configuration is that you can configure it through a web-based interface which is very streamlined, clean and easy to use or you can use a appveyor.yml file. This means that you can define your CI build process (including any scripts that might need to be run, etc.) in a standard file format (the YAML format) and store it in your repository. The benefits to that are huge. The file becomes a versioned artifact in your source control system, so it can be branched, merged, and is completely transparent to anyone working on the project. By the way, AppVeyor isn’t limited to just GitHub. It currently supports GitHub, BitBucket, Visual Studio Online, and Kiln. I did have a few issues getting one of my projects to build, but the same day I posted the problem to the support forum a fix was deployed, and I had a functioning CI build about 5 minutes after that. Since then, I’ve provided some additional feature requests and had a few other questions, all of which have seen responses within a 24-hour period. I have to say that it’s easily been one of the best customer support experiences I’ve seen in a long time. AppVeyor is still young, so it doesn’t yet have full feature parity with some of the older (more established) CI systems available,  but it’s getting better all the time and I have no doubt that it will quickly catch up to those other CI systems and then pass them. The bottom line, if you’re looking for a good cloud-hosted CI system for your .NET-based projects, look at AppVeyor.

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  • UPOS RFIDScanner data format

    - by Robert Snyder
    A lot of work that I do currently is based in the OPOS/UPOS world. My company has a device that can read 13.56Mhz tags (RFID), Smart Cards, and Mag Stripe cards. Up until somewhat recently I have only been working with RFID for a very specific scenario. That was to read UltraLight C and Desfire cards. These cards were all setup very specifically so that I could take the data read from those cards and force it into a MSR track2 format. The past couple of weeks, however, I have been working on reading RFID credit cards (since I have a Visa card I've been using mine), and Smart Card credit cards. (The visa card I have has both) In learning how to communicate with SmartCard and reading ISO7816 and EMVCO documents I became a little more familiar with how info is stored. But now I have a question regarding UPOS. The RFID data on my Visa is stored (and read) very similar to how the data is stored and read from the Smart Card on my Visa. Cool. Well in the UPOS spec for SmartCardRW the ReadData method returns a byte array. That's cool, I can just return all that data and then parse it as my heart desires. The RFID though has a LinkedList of Tags. Well this makes sense in terms of my Visa card (reminds me of a question I have in regards to SmartCard, but that is for another question) but what about ULC and Desfire, or for that matter any Mifare card. Pages, Files, Purses don't exactly fit the Tag profile. For instance lets just say I read pages 4-12 on my ULC card. Each page I read is 4 bytes long. Does this mean I have 9 tags in my LinkedList? Is my Tag id the page number? Or then how does that translate to Desfire? I open application 123456 and read file 1 and file 2, Do I have 2 tags? and if so what is my tag id? At least with my Visa I think that I have to use the Tag id (ex 5F24 for my expiration date) and value of {0x15, 0x10, 0x31} Part of me says yes..that makes sense. Another part of me says, "well if that is the case then why doesn't SmartCardRW have Tags?" So that is my question. How do I format my data from those different types of media? or is that the job of my Control Object (the application)? Is so how does it know? The only protocols I have are: // Summary: // Enumerates the available predefined RFID tag protocols the device supports. [Flags] public enum RFIDProtocols { EpcClass0 = 1, RFIDSdt0Plus = 2, EpcClass1 = 4, EpcClass1Gen2 = 8, EpcClass2 = 16, Iso14443A = 4096, Iso14443B = 8192, Iso15693 = 12288, Iso180006B = 16384, Other = 16777216, All = 1073741824, } If I use that well all of my cards that I have are all Iso14443A. I use the ATQA and the SAK to know what type of card I really have. There is no RFID property that lets me specify that. So I'm lost.

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  • BizTalk: Instance Subscription: Details

    - by Leonid Ganeline
    It has interesting behavior and it is not always what we are waiting for. An orchestration can be enlisted with many subscriptions. In other word it can have several Receive shapes. Usually the first Receive uses the Activation subscription but other Receives create the Instance subscriptions. [See “Publish and Subscribe Architecture” in MSDN] Here is a sample process. This orchestration has two receives. It is a typical Sequential Convoy. [See "BizTalk Server 2004 Convoy Deep Dive" in MSDN by Stephen W. Thomas]. Let's experiment started.   There are three typical scenarios. First scenario: everything is OK Activation subscription for the Sample message is created when the orchestration the SampleProcess is enlisted. The Instance subscription is created only when the SampleProcess orchestration instance is started and it is removed when the orchestration instance is ended. So far so good, the Message_2 was delivered exactly in this time interval and was consumed. Second scenario: no consumers Three Sample_2 messages were delivered. One was delivered before the SampleProcess was started and before the instance subscription was created. Second message was delivered in the correct time interval. The third one was delivered after the SampleProcess orchestration was ended and the instance subscription was removed. Note: ·         It was not the first Sample_2 was consumed. It was first in the queue but in was not waiting, it was suspended when it was delivered to the Message Box and didn’t have any subscribers at this moment. The first and the last Sample_2 messages were Suspended (Nonresumable) in the Message Box. For each of this message we have got two (!) service instances associated with this suspended message. One service instance has the ServiceClass of Messaging, and we can see its Error Description:   The second service instance has the ServiceClass of RoutingFailureReport, and we can see its Error Description:   Third scenario: something goes wrong Two Sample_2 messages were delivered. Both were delivered in the same interval when the SampleProcess orchestration was working and the instance subscription was created and was working too. First Sample_2 was consumed. The second Sample_2 has the subscription but the subscriber, the SampleProcess orchestration, will not consume it. After the SampleProcess orchestration is ended (And only after! I will discuss this in the next article.), it is suspended (Nonresumable). In this time only one service instance associated with this kind of scenario is suspended. This service instance has the ServiceClass of Orchestration, and we can see its Error Description: In the Message tab we will see the Sample_2 message in the Suspended (Resumable) status. Note: ·         This behavior looks ambiguous. We see here the orchestration consumes the extra message(s) and gets suspended together with those extra messages. These messages are not consumed in term of “processed by orchestration”. But they are consumed in term of the “delivered to the subscriber”. The receive shape in the orchestration is not received these extra messages. But these messages are routed to the orchestration.     Unified Sequential convoy  Now one more scenario. It is the unified sequential convoy. That means the activation subscription is for the same message type as it for the instance subscription. The Sample_2 message is now the Sample message. For simplicity the SampleProcess orchestration consumes only two Sample messages. Usually the orchestration consumes a lot of messages inside loop, but now it is only two of them. First message starts the orchestration, the second message goes inside this orchestration. Then the next pair of messages follows, and so on. But if the input messages follow in shorter intervals we have got the problem. We lost messages in unpredictable manner. Note: ·         Maybe the better behavior would be if the orchestration removes the instance subscription after the message is consumed, not in the end on the orchestration. Right now it is a “feature” of the BizTalk subscription mechanism.

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  • Scenarios for Throwing Exceptions

    - by Joe Mayo
    I recently came across a situation where someone had an opinion that differed from mine of when an exception should be thrown. This particular case was an issue opened on LINQ to Twitter for an Exception on EndSession.  The premise of the issue was that the poster didn’t feel an exception should be raised, regardless of authentication status.  As first, this sounded like a valid point.  However, I went back to review my code and decided not to make any changes. Here's my rationale: 1. The exception doesn’t occur if the user is authenticated when EndAccountSession is called. 2. The exception does occur if the user is not authenticated when EndAccountSession is called. 3. The exception represents the fact that EndAccountSession is not able to fulfill its intended purpose - to end the session.  If a session never existed, then it would not be possible to perform the requested action.  Therefore, an exception is appropriate. To help illustrate how to handle this situation, I've modified the following code in Program.cs in the LinqToTwitterDemo project to illustrate the situation: static void EndSession(ITwitterAuthorizer auth) { using (var twitterCtx = new TwitterContext(auth, "https://api.twitter.com/1/", "https://search.twitter.com/")) { try { //Log twitterCtx.Log = Console.Out; var status = twitterCtx.EndAccountSession(); Console.WriteLine("Request: {0}, Error: {1}" , status.Request , status.Error); } catch (TwitterQueryException tqe) { var webEx = tqe.InnerException as WebException; if (webEx != null) { var webResp = webEx.Response as HttpWebResponse; if (webResp != null && webResp.StatusCode == HttpStatusCode.Unauthorized) Console.WriteLine("Twitter didn't recognize you as having been logged in. Therefore, your request to end session is illogical.\n"); } var status = tqe.Response; Console.WriteLine("Request: {0}, Error: {1}" , status.Request , status.Error); } } } As expected, LINQ to Twitter wraps the exception in a TwitterQueryException as the InnerException.  The TwitterQueryException serves a very useful purpose through it's Response property.  Notice in the example above that the response has Request and Error proprieties.  These properties correspond to the information that Twitter returns as part of it's response payload.  This is often useful while debugging to help you understand why Twitter was unable to perform the  requested action.  Other times, it's cryptic, but that's another story.  At least you have some way of knowing in your code how to anticipate and handle these situations, along with having extra information to debug with. To sum things up, there are two points to make: when and why an exception should be raised and when to wrap and re-throw an exception in a custom exception type. I felt it was necessary to allow the exception to be raised because the called method was unable to perform the task it was designed for.  I also felt that it is inappropriate for a general library to do anything with exceptions because that could potentially hide a problem from the caller.  A related point is that it should be the exclusive decision of the application that uses the library on what to do with an exception.  Another aspect of this situation is that I wrapped the exception in a custom exception and re-threw.  This is a tough call because I don’t want to hide any stack trace information.  However, the need to make the exception more meaningful by including vital information returned from Twitter swayed me in the direction to design an interface that was as helpful as possible to library consumers.  As shown in the code above, you can dig into the exception and pull out a lot of good information, such as the fact that the underlying HTTP response was a 401 Unauthorized.  In all, trade-offs are seldom perfect for all cases, but combining the fact that the method was unable to perform its intended function, this is a library, and the extra information can be more helpful, it seemed to be the better design. @JoeMayo

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  • Doubts about several best practices for rest api + service layer

    - by TheBeefMightBeTough
    I'm going to be starting a project soon that exposes a restful api for business intelligence. It may not be limited to a restful api, so I plan to delegate requests to a service layer that then coordinates multiple domain objects (each of which have business logic local to the object). The api will likely have many calls as it is a long-term project. While thinking about the design, I recalled a few best practices. 1) Use command objects at the controller layer (I'm using Spring MVC). 2) Use DTOs at the service layer. 3) Validate in both the controller and service layer, though for different reasons. I have my doubts about these recommendations. 1) Using command objects adds a lot of extra single-purpose classes (potentially one per request). What exactly is the benefit? Annotation based validation can be done using this approach, sure. What if I have two requests that take the same parameters, but have different validation requirements? I would have to have two different classes with exactly the same members but different annotations? Bleh. 2) I have heard that using DTOs is preferable to parameters because it makes for more maintainable code down the road (say, e.g., requirements change and the service parameters need to be altered). I don't quite understand this. Shouldn't an api be more-or-less set in stone? I would understand that in the early phases of a project (or, especially, an entire company) the domain itself will not be well understood, and thus core domain objects may change along with the apis that manipulate these objects. At this point however the number of api methods should be small and their dependents few, so changes to the methods could easily be tolerated from a maintainability standpoint. In a large api with many methods and a substantial domain model, I would think having a DTO for potentially each domain object would become unwieldy. Am I misunderstanding something here? 3) I see validation in the controller and service layer as redundant in most cases. Why would I validate that parameters are not null and are in general well formed in the controller if the service is going to do exactly the same (and more). Couldn't I just do all the validation in the service and throw a runtime exception with a list of bad parameters then catch that in the controller to make the error messages more presentable? Better yet, couldn't I just make the error messages user-friendly in the service and let the exception trickle up to a global handler (ControllerAdvice in spring, for example)? Is there something wrong with either of these approaches? (I do see a use case for controller validation if the input does not map one-to-one with the service input, but since the controllers are for a rest api and not forms, the api parameters will probably map directly to service parameters.) I do also have a question about unchecked vs checked exceptions. Namely, I'm not really sure why I'd ever want to use a checked exception. Every time I have seen them used they just get wrapped into general exceptions (DomainException, SystemException, ApplicationException, w/e) to reduce the signature length of methods, or devs catch Exception rather than dealing with the App1Exception, App2Exception, Sys1Exception, Sys2Exception. I don't see how either of these practices is very useful. Why not just use unchecked exceptions always and catch the ones you actually do care about? You could just document what unchecked exceptions the method throws.

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  • Feynman's inbox

    - by user12607414
    Here is Richard Feynman writing on the ease of criticizing theories, and the difficulty of forming them: The problem is not just to say something might be wrong, but to replace it by something — and that is not so easy. As soon as any really definite idea is substituted it becomes almost immediately apparent that it does not work. The second difficulty is that there is an infinite number of possibilities of these simple types. It is something like this. You are sitting working very hard, you have worked for a long time trying to open a safe. Then some Joe comes along who knows nothing about what you are doing, except that you are trying to open the safe. He says ‘Why don’t you try the combination 10:20:30?’ Because you are busy, you have tried a lot of things, maybe you have already tried 10:20:30. Maybe you know already that the middle number is 32 not 20. Maybe you know as a matter of fact that it is a five digit combination… So please do not send me any letters trying to tell me how the thing is going to work. I read them — I always read them to make sure that I have not already thought of what is suggested — but it takes too long to answer them, because they are usually in the class ‘try 10:20:30’. (“Seeking New Laws”, page 161 in The Character of Physical Law.) As a sometime designer (and longtime critic) of widely used computer systems, I have seen similar difficulties appear when anyone undertakes to publicly design a piece of software that may be used by many thousands of customers. (I have been on both sides of the fence, of course.) The design possibilities are endless, but the deep design problems are usually hidden beneath a mass of superfluous detail. The sheer numbers can be daunting. Even if only one customer out of a thousand feels a need to express a passionately held idea, it can take a long time to read all the mail. And it is a fact of life that many of those strong suggestions are only weakly supported by reason or evidence. Opinions are plentiful, but substantive research is time-consuming, and hence rare. A related phenomenon commonly seen with software is bike-shedding, where interlocutors focus on surface details like naming and syntax… or (come to think of it) like lock combinations. On the other hand, software is easier than quantum physics, and the population of people able to make substantial suggestions about software systems is several orders of magnitude bigger than Feynman’s circle of colleagues. My own work would be poorer without contributions — sometimes unsolicited, sometimes passionately urged on me — from the open source community. If a Nobel prize winner thought it was worthwhile to read his mail on the faint chance of learning a good idea, I am certainly not going to throw mine away. (In case anyone is still reading this, and is wondering what provoked a meditation on the quality of one’s inbox contents, I’ll simply point out that the volume has been very high, for many months, on the Lambda-Dev mailing list, where the next version of the Java language is being discussed. Bravo to those of my colleagues who are surfing that wave.) I started this note thinking there was an odd parallel between the life of the physicist and that of a software designer. On second thought, I’ll bet that is the story for anybody who works in public on something requiring special training. (And that would be pretty much anything worth doing.) In any case, Feynman saw it clearly and said it well.

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  • Dallas First Regionals 2012&ndash; For Inspiration and Recognition of Science and Technology

    - by T
    Wow!  That is all I have to say after the last 3 days. Three full fun filled days in a world that fed the geek, sparked the competitor, inspired the humanitarian, encouraged the inventor, and continuously warmed my heart.  As part of the Dallas First Regionals, I was awed by incredible students who teach as much as they learn, inventive and truly caring mentors that make mentoring look easy, and completely passionate and dedicated volunteers that bring meaning to giving all that you have and making events fun and safe for all.  If you have any interest in innovation, robotics, or highly motivated students, I can’t recommend anything any higher than visiting a First Robotics event. This is my third year with First and I was honored enough to serve the Dallas First Regionals as both a Web Site evaluator and as the East Field Volunteer Coordinator.  This was also the first year my daughter volunteered with me.  My daughter and I both recognize how different the First program is from other team events.  The difference with First is that everyone is a first class citizen.   It is a difference we can feel through experiencing and observing interactions between executives, respected engineers, students, and event staff.  Even with a veracious competition, you still find a lot of cooperation and we never witnessed any belittling between teams or individuals. First Robotics coined the term “Gracious Professionalism”.   It's a way of doing things that encourages high-quality work, emphasizes the value of others, and respects individuals and the community.1 I was introduced to this term as the Volunteer Coordinator when I was preparing the volunteer instructional speech.  Through the next few days, I discovered it is truly core to everything that First does.  One of the ways First accomplishes Gracious Professionalism is by utilizing another term they came up with which is “CoopertitionTM”. At FIRST, CoopertitionTM is displaying unqualified kindness and respect in the face of fierce competition.1   One of the things I never liked about sports was the need to “destroy” the other team.  First has really found a way to integrate CoopertitionTM  into the rules so teams can be competitive and part of that competition rewards cooperation. Oh and did I mention it has ROBOTS!!!  This year it had basket ball playing Kinect connected, remote controlled, robots!  There are not words for how exciting these games are.  You HAVE to check out this years game, Rebound Rumble, on youtube or you can view live action on Dallas First Video (as of this posting, the recording haven’t posted yet but should be there soon).  There are also some images below. Whatever it is, these students get it and exemplify it and these mentors ooze with it.  I am glad that First supports these events so we can all learn and be inspired by these exceptional students and mentors.  I know that no matter how much I give, it will never compare to what I gain volunteering at First.  Even if you don’t have time to volunteer, you owe it to yourself to go check out one of these events.  See what the future holds, be inspired, be encouraged, take some knowledge, leave some knowledge and most of all, have FUN.  That is what First is all about and thanks to First, I get it.   First Dallas Regionals 2012 VIEW SLIDE SHOW DOWNLOAD ALL 1.  USFirst http://www.usfirst.org/aboutus/gracious-professionalism

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  • Good DBAs Do Baselines

    - by Louis Davidson
    One morning, you wake up and feel funny. You can’t quite put your finger on it, but something isn’t quite right. What now? Unless you happen to be a hypochondriac, you likely drag yourself out of bed, get on with the day and gather more “evidence”. You check your symptoms over the next few days; do you feel the same, better, worse? If better, then great, it was some temporal issue, perhaps caused by an allergic reaction to some suspiciously spicy chicken. If the same or worse then you go to the doctor for some health advice, but armed with some data to share, and having ruled out certain possible causes that are fixed with a bit of rest and perhaps an antacid. Whether you realize it or not, in comparing how you feel one day to the next, you have taken baseline measurements. In much the same way, a DBA uses baselines to gauge the gauge health of their database servers. Of course, while SQL Server is very willing to share data regarding its health and activities, it has almost no idea of the difference between good and bad. Over time, experienced DBAs develop “mental” baselines with which they can gauge the health of their servers almost as easily as their own body. They accumulate knowledge of the daily, natural state of each part of their database system, and so know instinctively when one of their databases “feels funny”. Equally, they know when an “issue” is just a passing tremor. They see their SQL Server with all of its four CPU cores running close 100% and don’t panic anymore. Why? It’s 5PM and every day the same thing occurs when the end-of-day reports, which are very CPU intensive, are running. Equally, they know when they need to respond in earnest when it is the first time they have heard about an issue, even if it has been happening every day. Nevertheless, no DBA can retain mental baselines for every characteristic of their systems, so we need to collect physical baselines too. In my experience, surprisingly few DBAs do this very well. Part of the problem is that SQL Server provides a lot of instrumentation. If you look, you will find an almost overwhelming amount of data regarding user activity on your SQL Server instances, and use and abuse of the available CPU, I/O and memory. It seems like a huge task even to work out which data you need to collect, let alone start collecting it on a regular basis, managing its storage over time, and performing detailed comparative analysis. However, without baselines, though, it is very difficult to pinpoint what ails a server, just by looking at a single snapshot of the data, or to spot retrospectively what caused the problem by examining aggregated data for the server, collected over many months. It isn’t as hard as you think to get started. You’ve probably already established some troubleshooting queries of the type SELECT Value FROM SomeSystemTableOrView. Capturing a set of baseline values for such a query can be as easy as changing it as follows: INSERT into BaseLine.SomeSystemTable (value, captureTime) SELECT Value, SYSDATETIME() FROM SomeSystemTableOrView; Of course, there are monitoring tools that will collect and manage this baseline data for you, automatically, and allow you to perform comparison of metrics over different periods. However, to get yourself started and to prove to yourself (or perhaps the person who writes the checks for tools) the value of baselines, stick something similar to the above query into an agent job, running every hour or so, and you are on your way with no excuses! Then, the next time you investigate a slow server, and see x open transactions, y users logged in, and z rows added per hour in the Orders table, compare to your baselines and see immediately what, if anything, has changed!

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  • Is the Internet Making us Smarter or Not?

    - by BuckWoody
    I’ve been reading recently about an exchange among some very bright folks, some who posit that the Internet with its instant-on, sometimes-right, big-statement-wins mentality is making people think in a more shallow way, teaching us to rely on others as experts and diluting our logical thought process. Others state that it broadens our perspective and extends our mental reach. Whenever I see this kind of exchange on two ends of a spectrum, I begin to wonder if both sides might be correct.   I can certainly say that I have changed my way of learning, reading, and social interactions because of the Internet. And my tolerance for reading long missives has indeed gone down. I tend to (mentally and literally) “bookmark” things I never seem to have time to get back to. But I also agree that I’ve been exposed to thoughts, ideas and people I never would have encountered any other way. So how to deal with this dichotomy?   Well, I’m going to go off and think about it. No, I’m really going to go off for a full week to a cabin I’ve rented in a National Forest in the Midwest. It has no indoor plumbing, phones, Internet connections or anything else – only a bed to sleep in and a place to cook a little. I’m taking one book, some paper, and a guitar with me and that’s it. I plan to spend my days walking, reading a little, playing a little on the guitar, but mostly just thinking. Those of you who know me might find this unusual. I’m an always-on, hyper-caffeinated, overly-busy, connected person. I haven’t taken a vacation in five years, at least for more than two or three days at a time. Even then, I keep us on the move constantly – our vacations aren’t cruises or anything like that. I check e-mail, post and all that. When I’m not on vacation, I live with and leverage lots of technology, and work with those that do the same. This, however, is a really “unplugged” event, and I’m hoping that it will let me unpack the things I’ve been stuffing in my head. I plan to spend a lot of time on a single subject, writing notes, thinking, and writing more notes.   So after I post tomorrow's “quote of the day” I’ll be “going dark” for a week. No twitter, FaceBook, LinkedIn, e-mail, chat, none of my five blogs will get updated, and I’ll have to turn in my two articles for InformIT.com early. I won’t have access to my college class portal, so my students will be without me for a week. I will really be offline. I’ll see you in a week – hopefully a little more educated. See you then.   Share this post: email it! | bookmark it! | digg it! | reddit! | kick it! | live it!

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  • Is the Internet Making us Smarter or Not?

    - by BuckWoody
    I’ve been reading recently about an exchange among some very bright folks, some who posit that the Internet with its instant-on, sometimes-right, big-statement-wins mentality is making people think in a more shallow way, teaching us to rely on others as experts and diluting our logical thought process. Others state that it broadens our perspective and extends our mental reach. Whenever I see this kind of exchange on two ends of a spectrum, I begin to wonder if both sides might be correct.   I can certainly say that I have changed my way of learning, reading, and social interactions because of the Internet. And my tolerance for reading long missives has indeed gone down. I tend to (mentally and literally) “bookmark” things I never seem to have time to get back to. But I also agree that I’ve been exposed to thoughts, ideas and people I never would have encountered any other way. So how to deal with this dichotomy?   Well, I’m going to go off and think about it. No, I’m really going to go off for a full week to a cabin I’ve rented in a National Forest in the Midwest. It has no indoor plumbing, phones, Internet connections or anything else – only a bed to sleep in and a place to cook a little. I’m taking one book, some paper, and a guitar with me and that’s it. I plan to spend my days walking, reading a little, playing a little on the guitar, but mostly just thinking. Those of you who know me might find this unusual. I’m an always-on, hyper-caffeinated, overly-busy, connected person. I haven’t taken a vacation in five years, at least for more than two or three days at a time. Even then, I keep us on the move constantly – our vacations aren’t cruises or anything like that. I check e-mail, post and all that. When I’m not on vacation, I live with and leverage lots of technology, and work with those that do the same. This, however, is a really “unplugged” event, and I’m hoping that it will let me unpack the things I’ve been stuffing in my head. I plan to spend a lot of time on a single subject, writing notes, thinking, and writing more notes.   So after I post tomorrow's “quote of the day” I’ll be “going dark” for a week. No twitter, FaceBook, LinkedIn, e-mail, chat, none of my five blogs will get updated, and I’ll have to turn in my two articles for InformIT.com early. I won’t have access to my college class portal, so my students will be without me for a week. I will really be offline. I’ll see you in a week – hopefully a little more educated. See you then.   Share this post: email it! | bookmark it! | digg it! | reddit! | kick it! | live it!

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  • Something about Property Management or &hellip; the understanding of SharePoint Admins/roles ?!?

    - by Enrique Lima
    When I talk about SharePoint, for some reason it comes to my mind as if it were property management and all the tasks associated with it. So, imagine you have a lot ( a piece of land of sorts), you then decide there is something you want to do with it.  So, you make the choice of having a building built.  Now, in order to go forward with your plan, you need to check what the rules/regulations are.  Has is it been zoned residential, commercial, industrial … you get the idea.  This to me sounds like Governance.  The what am I to do given a defined set of rules. We keep on moving forward based on those rules.  And with this we start the process of building, the building process takes us to survey the land, identify what our boundaries are.  And as we go along we start getting the idea in our head as to what we will do as far as the building goes.  We identify the essentials of the building, basic services and such.  All in all, we plan.  And as with many things we do, we like solid foundations.  What a solid foundation looks like will depend on where and what we build.  The way buildings are built depends in many ways in being able to foresee the potential for natural disasters or to try to leverage the lay of the land.  Sound familiar?  We have done our Requirements Gathering. We have the building in place, we have followed the zoning rules, we have implemented services.  But we need someone to manage the building, now we move on to the human side of the story.  We want to establish a means to normalcy in the building, someone that can be the monitoring agent as to the “what’s going on?” of it.  This person will be tasked with making sure all basic services are functional, that measures are taken if there is an issue and so on.  Enter the Farm Administrator. In a way, we establish an extension of the rules to make sure the building and the apartments/offices build follow a standard set of rules too. Now, in turn you will have people leasing or buying the apartments/offices, they will be the keepers of that space.  So, now we are building sites, we have moved from having the building (farm) ready, to leasing/selling offices/apartments (site collections).  There will be someone assuming responsibility for those offices, that person will authorize or be informed about activities and also who not only gets a code into the building, but perhaps a key to the office.  Enter Site Collection Administrator.  And then perhaps we move on to the person that would be responsible for specifics within the office, for example a Human Resources Manager or Coordinator.  They will have specific control and knowledge about people.  A facilities coordinator, and so on.  I would translate that into Site Administrators. With that said then, we identify the following: Role Name Responsibility (but not limited to) Farm Administrator Infrastructure Site Collection Admin Policies for Content, Hierarchy, Recycle Bin, Security and Access Site Owner (Site Admin) Security and Access, Training, Guidance, Manage Templates All in all there are different levels of responsibility to be handled, but it is very important to understand what they are and what they mean. Here is a link to very well laid out explanation on this … http://www.endusersharepoint.com/2009/08/11/site-managers-and-end-user-expectations-roles-and-responsibilities/

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