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• Grammatically correct double-noun identifiers, plural versions

  - by Michal Czardybon

  Consider compounds of two nouns, which in natural English would most often appear in the form "noun of noun", e.g. "direction of light", "output of a filter". When programming we usually write "LightDirection" and "FilterOutput". Now, I have a problem with plural nouns. There are two cases: 1) singular of plural e.g. "union of (two) sets", "intersection of (two) segments" Which is correct, SetUnion and SegmentIntersection or SetsUnion and SegmentsIntersection? 2) plural of plural There are two subcases: (a) Many elements, each having many related elements, e.g. "outputs of filters" (b) Many elements, each having single related element, e.g. "directions of vectors" Shell I use FilterOutputs and VectorDirections or FiltersOutputs and VectorsDirections? I suspect correct is the first version (FilterOutupts, VectorDirections), but I think it may lead to ambiguities, e.g. FilterOutputs - many outputs of a single filter or many outputs of many filters? LineSegmentProjections - projections of many segments or many projections of a single segment?

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• How Proxy server works with tcp/http connections?

  - by Vivek

  Since I am a beginner in the world of internet/networking, I always mess up with these kinds of doubts in my head while programming ;) .. My doubts are, While working behind a proxy, how my requests and responses work? Means my request headers and data will first reach to Proxy server- then proxy server sends it(same headers and data) to corresponding server. And server responses to it with a response header and body to the proxy server-then proxy server sends it to my computer. Wright? While using websockets we are upgrading our http connection to tcp. At this time what is happening @ Proxy server? Does the proxyserver also upgrades its connection to plain TCP? After opening such TCP connections, does the proxy server able to track/log those socket messsages? And most importantly, Is the proxy server transparent or acting like an original server infront of a client? Thanks for any answers or helpful links in advance.

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• How do I secure password parameters in RESTful web service URIs?

  - by adam

  i'm a newbie to server-side programming, so please forgive me if this gets messy. i've been contracted to create a web service to allow authenticated users to access a database. users have to enter a login and password. been reading and reading about REST vs SOAP, and i thought i'd settled on a RESTful design when i came across this statement: "Data that needs to be secure should not be sent as parameters in URIs." this seems like a major demerit against a RESTful approach. i'm aware that with https the password would be encrypted to prevent man-in-the-middle interception, but that leaves the server logs and client history as possible exposure points. is there a RESTful solution out there for this problem, or do i need to go SOAPy? any advice appreciated.

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• Create a javascript chome extention that does not execute in 6 months

  - by user1907657

  I have just started learning programming and I would like to make a script into a chrome extension. Its a basic script and I hope to practice more and more and develop bigger projects and set myself bigger tasks This script has to do the following : reload a page every 20 seconds (say google.com) after 6 months the script must not run (maybe prompt a window saying "its over 6 months") The code should be able to go into a small chrome extension and also the 6 month time period should be absolute not relative to the time the script was started; for example should the browser crash and i have to turn on the extension again it should not restart the 6 month counter. Also if anyone could recommend any good sources for JavaScript to learn (preferably books; nothingIi read online ever seems to stick)

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• Virtual directories as DB queries

  I have a site, e.g. site.com I would like users to be able to access it in their locale at site.com/somecity This is similar to craigslist, but they do it with subdomains e.g. sfbay.craigslist.org Using Apache HTTP server. MySql for DB. If you can provide a brief explanation and perhaps links to more thorough discussions, I would be quite interested in learning. I'm developing a web-app and wonder if I should focus some time to read up on Apache, or should I focus more of my time on server-side programming. Thanks!

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• SwingWorker exceptions lost even when using wrapper classes

  - by Ti Strga

  I've been struggling with the usability problem of SwingWorker eating any exceptions thrown in the background task, for example, described on this SO thread. That thread gives a nice description of the problem, but doesn't discuss recovering the original exception. The applet I've been handed needs to propagate the exception upwards. But I haven't been able to even catch it. I'm using the SimpleSwingWorker wrapper class from this blog entry specifically to try and address this issue. It's a fairly small class but I'll repost it at the end here just for reference. The calling code looks broadly like try { // lots of code here to prepare data, finishing with SpecialDataHelper helper = new SpecialDataHelper(...stuff...); helper.execute(); } catch (Throwable e) { // used "Throwable" here in desperation to try and get // anything at all to match, including unchecked exceptions // // no luck, this code is never ever used :-( } The wrappers: class SpecialDataHelper extends SimpleSwingWorker { public SpecialDataHelper (SpecialData sd) { this.stuff = etc etc etc; } public Void doInBackground() throws Exception { OurCodeThatThrowsACheckedException(this.stuff); return null; } protected void done() { // called only when successful // never reached if there's an error } } The feature of SimpleSwingWorker is that the actual SwingWorker's done()/get() methods are automatically called. This, in theory, rethrows any exceptions that happened in the background. In practice, nothing is ever caught, and I don't even know why. The SimpleSwingWorker class, for reference, and with nothing elided for brevity: import java.util.concurrent.ExecutionException; import javax.swing.SwingWorker; /** * A drop-in replacement for SwingWorker<Void,Void> but will not silently * swallow exceptions during background execution. * * Taken from http://jonathangiles.net/blog/?p=341 with thanks. */ public abstract class SimpleSwingWorker { private final SwingWorker<Void,Void> worker = new SwingWorker<Void,Void>() { @Override protected Void doInBackground() throws Exception { SimpleSwingWorker.this.doInBackground(); return null; } @Override protected void done() { // Exceptions are lost unless get() is called on the // originating thread. We do so here. try { get(); } catch (final InterruptedException ex) { throw new RuntimeException(ex); } catch (final ExecutionException ex) { throw new RuntimeException(ex.getCause()); } SimpleSwingWorker.this.done(); } }; public SimpleSwingWorker() {} protected abstract Void doInBackground() throws Exception; protected abstract void done(); public void execute() { worker.execute(); } }

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• Best approach to creating a database driven Java website?

  - by Craig Whitley

  I'm fairly new to programming and new to java, but I'd like to jump in the deep end with a little database driven website project. I've read quite a lot about requirements in the 'real world' requesting experience with Spring and Hibernate, so I have those installed on netbeans and a project created (if I hit run I get the default spring page). Now I just need a little guidance as to where to start designing my app (please tell me if I'm getting in a bit too over my head for a beginner!). Should I start off with my classes? - create all my classes as they map to my database tables and decide which attributes and methods each will require? Can anyone suggest any good books for maybe.. making a java based website from scratch (i.e. from design right through to deployment) that might be useful for a beginner? Any help appreciated thanks.

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• VBA long overflow

  - by HK_CH

  Hi I am trying to do some maths with my VBA excel (prime factorization) and I am hitting the limit of the long data type (runtime error 6 Overflow). Is there any way to get around this and still stay within VBA? (I am aware that the obvious one would be to use another more appropriate programming language) Thanks for help in advance! Thank you, it works in so far that I am able to get the big numbers into the variables now. However when I try to apply the MOD function (bignumber MOD 2 for example) it still fails with error message runtime error 6 Overflow.

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• How does compiling circular dependencies work?

  - by Fabio F.

  I've made the example in Java but I think (not tested) that it works in other (all?) languages. You have 2 files. First, M.java: public class MType { XType x; MType() {x = null;} } Second, another file (in the same directory), XType.java: public class XType { MType m; public XType(MType m) {this.m = m;} } Ok it's bad programming, but if you run javac XType it compiles: compiles even MType because XType needs it. But ... MType needs XType ... how does that work? How does the compiler know what is happening? Probably this is a stupid question, but I would like to know how the compiler (javac or any other compilers you know) manages that situation, not how to avoid it. I'm asking because i'm writing a precompiler and I would like to manage that situation.

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• Does program need additional symbols from .so shared library except those declared in header file?

  - by solotim

  In C programming, I thought that a object file can be successfully linked with a .so file as long as the .so file offers all symbols which have been declared in the header file. Suppose I have foo.c, bar.h and two libraries libbar.so.1 and libbar.so.2. The implementation of libbar.so.1 and libbar.so.2 is totally different, but I think it's OK as long as they both offers functions declared in bar.h. I linked foo.o with libbar.so.1 and produced an executable: foo.bin. This executable worked when libbar.so.1 is in LD_LIBRARY_PATH.(of course a symbolic link is made as libbar.so) However, when I change the symbolic link to libbar.so.2, foo.bin could not run and complainted this: undefined symbol: _ZSt4cerr I found this symbol type is 'B' and it does not appear in libbar.so.2. Obviously this symbol has nothing to do with those functions I decared in bar.h. What's wrong here?

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• Save user names on .txt file witch username is listed in /etc/passwd file. Bash

  - by user1448637

  well my goal is to make bash script to check if the username exist in /etc/passwd, if true i want to add it to the users.txt file. i am not really good at UNIX programming so i hope somebody help me. while(get to the end of /etc/passwd){ name=$(cat /etc/passwd | cut -d: -f1); num1=$(cat /etc/passwd | cut -d: -f3); num2=$(cat /etc/passwd | cut -d: -f4); if(num1==num2) /*i compare argv[0] with $name */ /* if true i=1 */ } if(i==1) save folowing string "argv[0]=agrv[1]" else "error message"

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• a Facebook app beginner question

  - by Robert

  Dear all, I have written up my first php script to learn facebook API stuff.It goes like this: require_once('facebook/client/facebook.php'); $facebook = new Facebook('0fff13540b7ff2ae94be38463cb4fa67','8a029798dd463be6c94cb8d9ca851696'); http://stackoverflow.com/questions/ask $fb_user = $facebook-require_login(); ? Hello ' useyou='false' possessive='true' /! Welcome to my first application! I put "facebook.php" in the same directory as my php script. However,after I deploy the php on a web server and link it with facebook and run it,I got error saying: "Fatal error: Call to undefined method Facebook::require_login() in /home/a2660104/public_html/facebook-php-sdk-94fcb13/src/default.php on line 16" Could anyone help me a bit on this?I am a beginner to the facebook app programming.Thanks a lot!

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• First and last window don't show up.

  - by SirGregg

  Hi, I'm creating a WinApi application for my programming course. The program is supposed to show an LED clock using a separate window for each 'block'. I have figured most of it out, except for one thing: when creating the two-dimensional array of windows, the first and last window never show up. Here's the piece of code from the InitInstance function: for (int x=0;x<8;x++) for (int y=0;y<7;y++) { digitWnd[x][y] = CreateWindowEx((WS_EX_LAYERED | WS_EX_TRANSPARENT | WS_EX_NOACTIVATE | WS_EX_STATICEDGE), szWindowClass, szTitle, (WS_POPUP| WS_BORDER), NULL, NULL, NULL, NULL, dummyWnd, NULL, hInstance, NULL); ShowWindow(digitWnd[x][y], nCmdShow); UpdateWindow(digitWnd[x][y]); } The same loop bounds are used everytime I interact with the windows (set position and enable/disable). All the windows seem to be working fine, except for digitWnd[0][0] and digitWnd[7][6]... Any ideas as to what is happening?

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• How do I convert a single char in string to an int

  - by Guest

  Keep in mind, if you choose to answer the question, I am a beginner in the field of programming and may need a bit more explanation than others as to how the solutions work. Thank you for your help. My problem is that I am trying to do computations with parts of a string (consisting only of numbers), but I do not know how to convert an individual char to an int. The string is named "message". for (int place = 0; place < message.size(); place++) { if (secondPlace == 0) { cout << (message[place]) * 100 << endl; } } Thank you.

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• Some Simple Questions for knowledge?

  - by dhaliwaljee

  Before Some days my friend ask me some simple questions, but I have no answer. Please tell me about these questions. How many computer programming languages are used all in the world ? I want to create a language like 'java or c#'. What is the procedure for creating a language and how it will create? Which language is used for manipulate Window operating system? What is the procedure of create Operating System like Windows/Linux/Mac and in which language it should create? What is the procedure of create open source framework project in javascript and php?

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• Debugging ASP.NET in VS

  - by negligible

  A lot of what I'm doing at the moment is figuring out other peoples code and adding or adapting functions, so currently I am debugging more than I am writing code of my own. I'm still new to this, Junior Developer, and I am always finding new ways to improve what I am doing. For example I recently found This Guide which had some excellent tips, such as overriding the ToString() method in your classes so children are readable from their parents. So I am looking for any other tips or tricks to make my debugging more efficient, as I recognise it as a big part of programming, that you more experienced programmers may have picked up or found. Anything appreciated, I can read websites just fine so no need to explain it yourself if you have a good link!

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• Claims-based Authentication: Are strings the essence of claims?

  - by Rising Star

  I've been programming with claims-based authentication for some time now with Windows Identity Foundation. It appears to me that in Windows Identity Foundation, once a user is logged in, the claims are basically strings of information that describe the user. With the old role-based authentication, I could say that a user is or is not a member of a given group, but with claims-based authentication, I can now have strings of information that describe a user. "This user is female". This user was born on "July 6, 1975". "This user logged in using a USB key". Is it the essence of claims-based authentication,that I have strings of information about the user given to the application by the framework?

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• General question: Filesystem or database?

  - by poeschlorn

  Hey guys, i want to create a small document management system. there are several users who store their files. each file which is uploaded contains an info which user uploaded it and the document content itself. In a view there are displayed all files of ONE specific user, ordered by date. What would be better: 1) giving the documents a name or metadata(XML) which contain the date and user (and iterate through them to get the metadata) or 2) giving the files a random/unique name and store metadata in a DB? something like this: date | user | filename What would you say and why? The used programming language is java and the DB is MySQL.

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• Existing SQL database android help

  - by basketball4567

  Hey guys, I am new to android programming and i am trying to make an app that will interface with a website i have. It is a movie website with all of its information stored in SQL database. I know how to write the requests and queries in .asp but dont know how to get information from the database in my app. I want the user to be able to enter a movie title, and through a couple of stored procedures that are in my SQL database, return the info on that movie(actor, budget, genre....). I would like to have little info stored on the device, have all of the queries being sent to my SQL server and just have the info being returned. So my question boils down to, how do i link my existing SQL database with an android app. Any help would be great. Thanks Basketball4567

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• How to create an iPad directory view like animation?

  - by mahes25

  In the recent iOS 4.2 update, Apple introduced a nice animation for creating one level directories. I am trying to figure out how to implement a similar animation in my project. I would deeply appreciate it if anyone could give me any pointers to do this efficiently. From my investigation, I believe this animation or effect could be done very efficiently using Core Image which would allow me to write a custom filter. Unfortunately, Core Image is not available in iPhone. So how can do it? I read a blog post that explained a core animation scheme to create an iPad flip clock. The problem I have is similar but has important differences. Besides, I not excited about saving the subimage combinations, which I believe can cause a memory issue. Please enlighten me on the possible ways of doing this animation. I am relatively new to iOS programming, so I might have missed obvious ways of doing this animation or effect.

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• Is It Worth Using Bitwise Operators In Methods?

  - by user1626141

  I am very new to Java (and programming in general, my previous experience is with ActionScript 2.0 and some simple JavaScript), and I am working my way slowly and methodically through Java: A Beginner's Guide by Herbert Schildt. It is an incredible book. For one thing, I finally understand more-or-less what bitwise operators (which I first encountered in ActionScript 2.0) do, and that they are more efficient than other methods for certain sums. My question is, is it more efficient to use a method that uses, say, a shift right, to perform all your divisions/2 (or divisions/even) for you in a large program with many calculations (in this case, a sprawling RPG), or is it more efficient to simply use standard mathematical operations because the compiler will optimise it all for you? Or, am I asking the wrong question entirely?

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• gdb + nasm debug info not being created

  - by cpowel2

  I am relatively new to assembly language programming and am trying to debug a small .asm file that I wrote in Ubuntu. I am however running into an issue where my symbol table is not being loaded and was looking for some help. I am compiling my program as follows. nasm -f elf -g -F dwarf bs.asm gcc -m32 -g bs.o -o bs which produces the executable bs when I run gdb bs I get a message that says no debugging symbols and when I try to set a break point by b main it says function not defined even though its in the file and I can run it using ./bs I read a couple posts that suggested adding the -F dwarf when assembling but that didn't help if anyone has any insight I would greatly appreciated your input. Thanks in advance

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• What books help one to learn to read code?

  - by Daniel

  Lion's Commentary on Unix Sixth Edition with Source Code is a wonderful book to learn how to read code. Reading code is important -- how does one learn how to write excellent code without having read excellent code? But, sadly, while great writers, of fiction and non-fiction, all spend a great deal of time reading stuff, we, programmers, seem to avoid it like the plague. Worse still, programming books usually go the same way. They might show a pattern or a style, but they often avoid showing good, complex code, and helping one go through it. There are exceptions, of course. I hope. So, with that in mind, what books are to be found which help one learn how to read code?

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• Retrieving content of a txt file from URL to Android

  - by eightx2

  I would like to be able to retrieve contents of a .txt file from the internet, and load it in an EditText. I tried using the code on this page: Reading Text File From Server on Android It didn't work, as you might have guessed. I've read on numerous sites about this type of problem, but I can't get anything to work. Someone suggested AndroidHttpClient (http://developer.android.com/reference/android/net/http/AndroidHttpClient.html), but I simply can't find any examples with this. As I'm a newbie in Android programming, I would love if someone could please give me a small example.

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• Questions about "casting operation" in OOP

  - by rhapsodyn

  When programming, we usually use some type-casting operations. When the casting happens on the objects "on the same level", it feels ok. But when it happens on the ojects "on the different levels"(mainly between father and son), it feels weird. Considering this: Class Son extends Father WhenSon s = (Son)father;, it's absolutely unreasonable. Because a "Son" is not a "Father" anymore, "Son" may grow up with some new properties "Father" doesn't have, the casting operation makes these properties unknown. On the other hand, Father f = (Father)son seems reasonable, but according to LSP "An instance of a derived should be able to replace any instance of its superclass" A "Son" can do anything his "Father" can, so the casting operation seems useless. So can i say that these casting operations are agaisnt OO design principle but necessary?

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