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  • Understanding how software testing works and what to test.

    - by RHaguiuda
    Intro: I've seen lots of topics here on SO about software testing and other terms I don't understand. Problem: As a beginner developer I, unfortunately, have no idea how software testing works, not even how to test a simple function. This is a shame, but thats the truth. I also hope this question can help others beginners developers too. Question: Can you help me to understand this subject a little bit more? Maybe some questions to start would help: When I develop a function, how should I test it? For example: when working with a sum function, should I test every input value possible or just some limits? How about testing functions with strings as parameters? In a big program, do I have to test every single piece of code of it? When you guys program do you test every code written? How automated test works and how can I try one? How tools for automated testing works and what they do? I`ve heard about unit testing. Can I have a brief explanation on this? What is a testing framework? If possible please post some code with examples to clarify the ideas. Any help on this topic is very welcome! Thanks.

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  • Should my validator have access to my entire model?

    - by wb
    As the title states I'm wondering if it's a good idea for my validation class to have access to all properties from my model. Ideally, I would like to do that because some fields require 10+ other fields to verify whether it is valid or not. I could but would rather not have functions with 10+ parameters. Or would that make the model and validator too coupled with one another? Here is a little example of what I mean. This code however does not work because it give an infinite loop! Class User Private m_UserID Private m_Validator Public Sub Class_Initialize() End Sub Public Property Let Validator(value) Set m_Validator = value m_Validator.Initialize(Me) End Property Public Property Get Validator() Validator = m_Validator End Property Public Property Let UserID(value) m_UserID = value End property Public Property Get UserID() UserID = m_Validator.IsUserIDValid() End property End Class Class Validator Private m_User Public Sub Class_Initialize() End Sub Public Sub Initialize(value) Set m_User = value End Sub Public Function IsUserIDValid() IsUserIDValid = m_User.UserID > 13 End Function End Class Dim mike : Set mike = New User mike.UserID = 123456 mike.Validator = New Validator Response.Write mike.UserID If I'm right and it is a good idea, how can I go a head and fix the infinite loop with the get property UserID? Thank you.

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  • Combobox having values but not showing text

    - by ras
    hi, I'm using GWT-EXT combobox. My problem is when I render the combobox, it's having as many rows as it has values but all the rows are empty means text is not shown. Here's my code. Combobox cb = new Combobox(); cb.setForceSelection(true); cb.setMinChars(1); cb.setWidth(200); cb.setStore(store); // Store is perfectly loaded in combobox cb.setDisplayField("ReportName"); cb.setMode(ComboBox.LOCAL); cb.setTriggerAction(ALL); cb.setEmptyText("--Select--"); cb.setLoadingText("Searching..."); cb.setTypeAhead(true); cb.setSelectOnFocus(true); All other code is working fine. I'm sure for one thing that this problem is related to one of the functions of Combobox. Thanks in advance.

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  • linear combinations in python/numpy

    - by nmaxwell
    greetings, I'm not sure if this is a dumb question or not. Lets say I have 3 numpy arrays, A1,A2,A3, and 3 floats, c1,c2,c3 and I'd like to evaluate B = A1*c1+ A2*c2+ A3*c3 will numpy compute this as for example, E1 = A1*c1 E2 = A2*c2 E3 = A3*c3 D1 = E1+E2 B = D1+E3 or is it more clever than that? In c++ I had a neat way to abstract this kind of operation. I defined series of general 'LC' template functions, LC for linear combination like: template<class T,class D> void LC( T & R, T & L0,D C0, T & L1,D C1, T & L2,D C2) { R = L0*C0 +L1*C1 +L2*C2; } and then specialized this for various types, so for instance, for an array the code looked like for (int i=0; i<L0.length; i++) R.array[i] = L0.array[i]*C0 + L1.array[i]*C1 + L2.array[i]*C2; thus avoiding having to create new intermediate arrays. This may look messy but it worked really well. I could do something similar in python, but I'm not sure if its nescesary. Thanks in advance for any insight. -nick

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  • Passing data between Drupal module callback, preprocess and template

    - by rob5408
    I've create a module called finder that I want to take parameters from a url, crunch them and then display results via a tpl file. here's the relevant functions... function finder_menu() { $items = array(); $items['finder'] = array( 'page callback' => 'finder_view', 'access callback' => TRUE, ); return $items; } function finder_theme($existing, $type, $theme, $path) { return array( 'finder_view' => array( 'variables' => array('providers' => null), 'template' => 'results', ), ); } function finder_preprocess_finder_view(&$variables) { // put my data into $variables } function finder_view($zipcode = null) { // Get Providers from Zipcode return theme('finder_view', $providers); } Now I know finder_view is being called. I also know finder_preprocess_finder_view is being called. Finally, I know that result.tpl.php is being used to output. But I cannot wrap my head around how to do meaningful work in the callback, somehow make that data available in the preprocessor to add to "variables" so that i can access in the tpl file. in a situation where you are using a tpl file is the callback even useful for anything? I've done this in the past where the callback does all the work and passes to a theming function, but i want to use a file for output instead this time. Thanks...

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  • How Can I Find a List of All Exceptions That a Given Library Function Throws in Python?

    - by b14ck
    Sorry for the long title, but it seems most descriptive for my question. Basically, I'm having a difficult time finding exception information in the official python documentation. For example, in one program I'm currently writing, I'm using the shutil libary's move function: from shutil import move move('somefile.txt', '/tmp/somefile.txt') That works fine, as long as I have write access to /tmp/, there is enough diskspace, and if all other requirements are satisfied. However, when writing generic code, it is often difficult to guarantee those factors, so one usually uses exceptions: from shutil import move try: move('somefile.txt', '/tmp/somefile.txt') except: print 'Move failed for some reason.' I'd like to actually catch the appropriate exceptions thrown instead of just catching everything, but I simply can't find a list of exceptions thrown for most python modules. Is there a way for me to see which exceptions a given function can throw, and why? This way I can make appropriate cases for each exception, eg: from shutil import move try: move('somefile.txt', '/tmp/somefile.txt') except PermissionDenied: print 'No permission.' except DestinationDoesNotExist: print "/tmp/ doesn't exist" except NoDiskSpace: print 'No diskspace available.' Answer points go to whoever can either link me to some relevant documentation that I've somehow overlooked in the official docs, or provide a sure-fire way to figure out exactly which exceptions are thrown by which functions, and why. Thanks!

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  • IE 7 activex object (or xmlhttprequest?) open method using POST takes 20-30 seconds to return

    - by Toddeman
    i have a problem that only shows itself in IE7. its a simple ajax call. i got my object (accounting for the browser) so in 7 i SHOULD have an ActiveXObject. when i call open with POST, it takes 20-30 seconds to return. i am using a TON of GET calls to populate information and all of these work (finally, after some bug fixing), but i am NOT a web developer so much like the other bugs i had to fix, i figured i was just missing another IE anomaly. this is not a consistent bug either, which makes it harder to find for me. most times the POST functions like it does in Firefox or Chrome, but maybe 1 out of 4 or 5 will take 20-30 seconds to return. it DOES return correctly when it returns, it just takes a long time. am i missing something simple? or is there a smarter way for me to find out exactly what is going on (like the equivalent of the firebug 'net' tab for windows?).

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  • What is a fast way to set debugging code at a given line in a function?

    - by Josh O'Brien
    Preamble: R's trace() is a powerful debugging tool, allowing users to "insert debugging code at chosen places in any function". Unfortunately, using it from the command-line can be fairly laborious. As an artificial example, let's say I want to insert debugging code that will report the between-tick interval calculated by pretty.default(). I'd like to insert the code immediately after the value of delta is calculated, about four lines up from the bottom of the function definition. (Type pretty.default to see where I mean.) To indicate that line, I need to find which step in the code it corresponds to. The answer turns out to be step list(c(12, 3, 3)), which I zero in on by running through the following steps: as.list(body(pretty.default)) as.list(as.list(body(pretty.default))[[12]]) as.list(as.list(as.list(body(pretty.default))[[12]])[[3]]) as.list(as.list(as.list(body(pretty.default))[[12]])[[3]])[[3]] I can then insert debugging code like this: trace(what = 'pretty.default', tracer = quote(cat("\nThe value of delta is: ", delta, "\n\n")), at = list(c(12,3,3))) ## Try it a <- pretty(c(1, 7843)) b <- pretty(c(2, 23)) ## Clean up untrace('pretty.default') Questions: So here are my questions: Is there a way to print out a function (or a parsed version of it) with the lines nicely labeled by the steps to which they belong? Alternatively, is there another easier way, from the command line, to quickly set debugging code for a specific line within a function? Addendum: I used the pretty.default() example because it is reasonably tame, but with real/interesting functions, repeatedly using as.list() quickly gets tiresome and distracting. Here's an example: as.list(as.list(as.list(as.list(as.list(as.list(as.list(as.list(as.list(body(# model.frame.default))[[26]])[[3]])[[2]])[[4]])[[3]])[[4]])[[4]])[[4]])[[3]]

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  • Trait, FunctionN, or trait-inheriting-FunctionN in Scala?

    - by Willis Blackburn
    I have a trait in Scala that has a single method. Call it Computable and the single method is compute(input: Int): Int. I can't figure out whether I should Leave it as a standalone trait with a single method. Inherit from (Int = Int) and rename "compute" to "apply." Just get rid of Computable and use (Int = Int). A factor in favor of it being a trait is that I could usefully add some additional methods. But of course if they were all implemented in terms of the compute method then I could just break them out into a separate object. A factor in favor of just using the function type is simplicity and the fact that the syntax for an anonymous function is more concise than that for an anonymous Computable instance. But then I've no way to distinguish objects that are actually Computable instances from other functions that map Int to Int but aren't meant to be used in the same context as Computable. How do other people approach this type of problem? No right or wrong answers here; I'm just looking for advice.

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  • LuaEdit can't find module when Lua files all in the same folder

    - by joverboard
    I downloaded LuaEdit to use as an IDE and debug tool however I'm having trouble using it for even the simplest things. I've created a solution with 2 files in it, all of which are stored in the same folder. My files are as follows: --startup.lua require("foo") test("Testing", "testing", "one, two, three") --foo.lua foo = {} print("In foo.lua") function test(a,b,c) print(a,b,c) end This works fine when in my C++ compiler when accessed through some embed code, however when I attempt to use the same code in LuaEdit, it crashes on line 3 require("foo") with an error stating: module 'foo' not found: no field package.preload['foo'] no file 'C:\Program Files (x86)\LuaEdit 2010\lua\foo.lua' no file 'C:\Program Files (x86)\LuaEdit 2010\lua\foo\init.lua' no file 'C:\Program Files (x86)\LuaEdit 2010\foo.lua' no file 'C:\Program Files (x86)\LuaEdit 2010\foo\init.lua' no file '.\foo.lua' no file 'C:\Program Files (x86)\LuaEdit 2010\foo.dll' no file 'C:\Program Files (x86)\LuaEdit 2010\loadall.dll' no file '.\battle.dll' I have also tried creating these files prior to adding them to a solution and still get the same error. Is there some setting I'm missing? It would be great to have an IDE/debugger but it's useless to me if it can't run linked functions.

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  • C++ Implicit Conversion Operators

    - by Imbue
    I'm trying to find a nice inheritance solution in C++. I have a Rectangle class and a Square class. The Square class can't publicly inherit from Rectangle, because it cannot completely fulfill the rectangle's requirements. For example, a Rectangle can have it's width and height each set separately, and this of course is impossible with a Square. So, my dilemma. Square obviously will share a lot of code with Rectangle; they are quite similar. For examlpe, if I have a function like: bool IsPointInRectangle(const Rectangle& rect); it should work for a square too. In fact, I have a ton of such functions. So in making my Square class, I figured I would use private inheritance with a publicly accessible Rectangle conversion operator. So my square class looks like: class Square : private Rectangle { public: operator const Rectangle&() const; }; However, when I try to pass a Square to the IsPointInRectangle function, my compiler just complains that "Rectangle is an inaccessible base" in that context. I expect it to notice the Rectangle operator and use that instead. Is what I'm trying to do even possible? If this can't work I'm probably going to refactor part of Rectangle into MutableRectangle class. Thanks.

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  • Setting objct literal property value via asynchronous callback.

    - by typeof
    I'm creating a self-contained javascript utility object that detects advanced browser features. Ideally, my object would look something like this: Support = { borderRadius : false, // values returned by functions gradient : false, // i am defining dataURI : true }; My current problem deals with some code I'm adapting from Weston Ruter's site which detects dataURI support. It attempts to use javascript to create an image with a dataURI source, and uses onload/onerror callbacks to check the width/height. Since onload is asynchronous, I lose my scope and returning true/false does not assign true/false to my object. Here is my attempt: Support = { ... dataURI : function(prop) { prop = prop; // keeps in closure for callback var data = new Image(); data.onload = data.onerror = function(){ if(this.width != 1 || this.height != 1) { that = false; } that = true; } data.src = "data:image/gif;base64,R0lGODlhAQABAIAAAAAAAP///ywAAAAAAQABAAACAUwAOw=="; return -1; }(this) }; I'm executing the anonymous function immediately, passing this (which I hoped was a reference to Support.dataURI), but unfortunately references the window object -- so the value is always -1. I can get it to work by using an externally defined function to assign the value after the Support object is created... but I don't think it's very clean that way. Is there a way for it to be self-contained? Can the object literal's function reference the property it's assigned to?

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  • Recursion in assembly?

    - by Davis
    I'm trying to get a better grasp of assembly, and I am a little confused about how to recursively call functions when I have to deal with registers, popping/pushing, etc. I am embedding x86 assembly in C++. Here I am trying to make a method which given an array of integers will build a linked list containing these integers in the order they appear in the array. I am doing this by calling a recursive function: insertElem (struct elem *head, struct elem *newElem, int data) -head: head of the list -data: the number that will be inserted at the end of a list -newElem: points to the location in memory where I will store the new element (data field) My problem is that I keep overwriting the registers instead of a typical linked list. For example, if I give it an array {2,3,1,8,3,9} my linked-list will return the first element (head) and only the last element, because the elements keep overwriting each other after head is no longer null. So here my linked list looks something like: 2--9 instead of 2--3--1--8--3--9 I feel like I don't have a grasp on how to organize and handle the registers. newElem is in EBX and just keeps getting rewritten. Thanks in advance!

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  • Are there any libraries for parsing "number expressions" like 1,2-9,33- in Java

    - by mihi
    Hi, I don't think it is hard, just tedious to write: Some small free (as in beer) library where I can put in a String like 1,2-9,33- and it can tell me whether a given number matches that expression. Just like most programs have in their print range dialogs. Special functions for matching odd or even numbers only, or matching every number that is 2 mod 5 (or something like that) would be nice, but not needed. The only operation I have to perform on this list is whether the range contains a given (nonnegative) integer value; more operations like max/min value (if they exist) or an iterator would be nice, of course. What would be needed that it does not occupy lots of RAM if anyone enters 1-10000000 but the only number I will ever query is 12345 :-) (To implement it, I would parse a list into several (min/max/value/mod) pairs, like 1,10,0,1 for 1-10 or 11,33,1,2 for 1-33odd, or 12,62,2,10 for 12-62/10 (i. e. 12, 22, 32, ..., 62) and then check each number for all the intervals. Open intervals by using Integer.MaxValue etc. If there are no libs, any ideas to do it better/more efficient?)

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  • Socket isn't listed by netstat unless using certain ports

    - by illuzive
    I'm a computer science student with a few years of programming experience. Yesterday, while working on a project (Mac OS X, BSD sockets) at school, I encountered a strange problem. I was adding several modules to a very basic "server" (mostly a bunch of functions to set up and manage an UDP socket on a certain port). While doing this, I started the server from time to time in order to see that everything worked like it should. I've been using port 32000 during the development of the server. When I start the server and run netstat, the socket is listed as expected. > netstat -p UDP | grep 32000 udp46 0 0 *.32000 *.* However, when I run the server on other ports (random (10000 - 50000)), it's not listed by netstat. My thought was that I had somehow hard coded the port somewhere in the code, but that's not the case. The thing is - I can connect to the socket on any of the tested ports, and it reads data sent to it without any problem at all. It just doesn't get listed by netstat. What I wonder, is if anyone of you have any idea of why this happens? Note: Although this is a project at school, it's not homework. This is just something I want to understand for my own benefit.

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  • Partial template specialization for more than one typename

    - by Matt Joiner
    In the following code, I want to consider functions (Ops) that have void return to instead be considered to return true. The type Retval, and the return value of Op are always matching. I'm not able to discriminate using the type traits shown here, and attempts to create a partial template specialization based on Retval have failed due the presence of the other template variables, Op and Args. How do I specialize only some variables in a template specialization without getting errors? Is there any other way to alter behaviour based on the return type of Op? template <typename Retval, typename Op, typename... Args> Retval single_op_wrapper( Retval const failval, char const *const opname, Op const op, Cpfs &cpfs, Args... args) { try { CallContext callctx(cpfs, opname); Retval retval; if (std::is_same<bool, Retval>::value) { (callctx.*op)(args...); retval = true; } else { retval = (callctx.*op)(args...); } assert(retval != failval); callctx.commit(cpfs); return retval; } catch (CpfsError const &exc) { cpfs_errno_set(exc.fserrno); LOGF(Info, "Failed with %s", cpfs_errno_str(exc.fserrno)); } return failval; }

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  • How to encapsulate a WinAPI application into a C++ class

    - by Semen Semenych
    There is a simple WinAPI application. All it does currently is this: register a window class register a tray icon with a menu create a value in the registry in order to autostart and finally, it checks if it's unique using a mutex As I'm used to writing code mainly in C++, and no MFC is allowed, I'm forced to encapsulate this into C++ classes somehow. So far I've come up with such a design: there is a class that represents the application it keeps all the wndclass, hinstance, etc variables, where the hinstance is passed as a constructor parameter as well as the icmdshow and others (see WinMain prototype) it has functions for registering the window class, tray icon, reigstry information it encapsulates the message loop in a function In WinMain, the following is done: Application app(hInstance, szCmdLIne, iCmdShow); return app.exec(); and the constructor does the following: registerClass(); registerTray(); registerAutostart(); So far so good. Now the question is : how do I create the window procedure (must be static, as it's a c-style pointer to a function) AND keep track of what the application object is, that is, keep a pointer to an Application around. The main question is : is this how it's usually done? Am I complicating things too much? Is it fine to pass hInstance as a parameter to the Application constructor? And where's the WndProc? Maybe WndProc should be outside of class and the Application pointer be global? Then WndProc invokes Application methods in response to various events.

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  • File streaming in PHP - How to replicate this C#.net code in PHP?

    - by openid_kenja
    I'm writing an interface to a web service where we need to upload configuration files. The documentation only provides a sample in C#.net which I am not familiar with. I'm trying to implement this in PHP. Can someone familiar with both languages point me in the right direction? I can figure out all the basics, but I'm trying to figure out suitable PHP replacements for the FileStream, ReadBytes, and UploadDataFile functions. I believe that the RecService object contains the URL for the web service. Thanks for your help! private void UploadFiles() { clientAlias = “<yourClientAlias>”; string filePath = “<pathToYourDataFiles>”; string[] fileList = {"Config.txt", "ProductDetails.txt", "BrandNames.txt", "CategoryNames.txt", "ProductsSoldOut.txt", "Sales.txt"}; RecommendClient RecService = new RecommendClient(); for (int i = 0; i < fileList.Length; i++) { bool lastFile = (i == fileList.Length - 1); //start generator after last file try { string fileName = filePath + fileList[i]; if (!File.Exists(fileName)) continue; // file not found } // set up a file stream and binary reader for the selected file and convert to byte array FileStream fStream = new FileStream(fileName, FileMode.Open, FileAccess.Read); BinaryReader br = new BinaryReader(fStream); byte[] data = br.ReadBytes((int)numBytes); br.Close(); // pass byte array to the web service string result = RecService.UploadDataFile(clientAlias, fileList[i], data, lastFile); fStream.Close(); fStream.Dispose(); } catch (Exception ex) { // log an error message } } }

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  • Extracting function declarations from a PHP file

    - by byronh
    I'm looking to create an on-site API reference for my framework and application. Basically, say I have a class file model.class.php: class Model extends Object { ... code here ... // Separates results into pages. // Returns Paginator object. final public function paginate($perpage = 10) { ... more code here ... } } and I want to be able to generate a reference that my developers can refer to quickly in order to know which functions are available to be called. They only need to see the comments directly above each function and the declaration line. Something like this (similar to a C++ header file): // Separates results into pages. // Returns Paginator object. final public function paginate($perpage = 10); I've done some research and this answer looked pretty good (using Reflection classes), however, I'm not sure how I can keep the comments in. Any ideas? EDIT: Sorry, but I want to keep the current comment formatting. Myself and the people who are working on the code hate the verbosity associated with PHPDocumentor. Not to mention a comment-rewrite of the entire project would take years, so I want to preserve just the // comments in plaintext.

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  • Updating section in ConfigParser (or an alternative)

    - by lyrae
    I am making a plugin for another program and so I am trying to make thing as lightweight as possible. What i need to do is be able to update the name of a section in the ConfigParser's config file. [project name] author:john doe email: [email protected] year: 2010 I then have text fields where user can edit project's name, author, email and year. I don't think changing [project name] is possible, so I have thought of two solutions: 1 -Have my config file like this: [0] projectname: foobar author:john doe email: [email protected] year: 2010 that way i can change project's name just like another option. But the problem is, i would need the section # to be auto incremented. And to do this i would have to get every section, sort of, and figure out what the next number should be. The other option would be to delete the entire section and its value, and re-add it with the updated values which would require a little more work as well, such as passing a variable that holds the old section name through functions, etc, but i wouldn't mind if it's faster. Which of the two is best? or is there another way? I am willing to go with the fastest/lightweight solution possible, doesn't matter if it requires more work or not.

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  • Where to store site settings: DB? XML? CONFIG? CLASS FILES?

    - by Emin
    I am re-building a news portal of which already have a large number of visits every day. One of the major concerns when re-building this site was to maximize performance and speed. Having said this, we have done many things from caching, to all sort of other measures to ensure speed. Now towards the end of the project, I am having a dilemma of where to store my site settings that would least affect performance. The site settings will include things such as: Domain, DefaultImgPath, Google Analytics code, default emails of editors as well as more dynamic design/display feature settings such as the background color of specific DIVs and default color for links etc.. As far as I know, I have 4 choices in storing all these info. Database: Storing general settings in the DB and caching them may be a solution however, I want to limit the access to the database for only necessary and essential functions of the project which generally are insert/update/delete news items, author articles etc.. XML: I can store these settings in an XML file but I have not done this sort of thing before so I don't know what kind of problems -if any- I might face in the future. CONFIG: I can also store these settings in web.config CLASS FILE: I can hard code all these settings in a SiteSettings class, but since the site admin himself will be able to edit these settings, It may not be the best solution. Currently, I am more close to choosing web.config but letting people fiddle with it too often is something I do not want. E.g. if somehow, I miss out a validation for something and it breaks the web.config, the whole site will go down. My concern basically is that, I cannot forsee any possible consequences of using any of the methods above (or is there any other?), I was hoping to get this question over to more experienced people out here who hopefully help make my decision.

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  • SWIG interface to receive an opaque struct reference in Java through function argument

    - by Beeo
    I am trying to use SWIG in order to use the Spotify API (libspotify) for Android: https://developer.spotify.com/technologies/libspotify/ I am having trouble defining the SWIG interface file to be able to successfully call the following native C function: sp_error sp_session_create(const sp_session_config * config, sp_session ** sess); Which in C would be called like this: //config struct defined previously sp_session *sess; sp_session_create(&config, &sess); But in Java I would need to call it like this: //config object defined previously sp_session javaSess = new sp_session(); sp_session_create(config, javaSess); sp_session is an opaque struct and is only defined in libspotify's API.h file as: typedef struct sp_session sp_session; I'm expecting the libspotify library to create it and give me a reference to it. The only thing I need that reference for then is to pass to other functions in the API. I believe the answer lies within the SWIG interface and typemaps, but I have been unsuccessful in trying to apply the examples I found in the documentation: http://www.swig.org/Doc2.0/SWIGDocumentation.html#Java_struct_pointer_pointer `http://www.swig.org/Doc2.0/SWIGDocumentation.html#Java_using_typemaps_return_arguments Help!

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  • Object equality in context of hibernate / webapp

    - by bert
    How do you handle object equality for java objects managed by hibernate? In the 'hibernate in action' book they say that one should favor business keys over surrogate keys. Most of the time, i do not have a business key. Think of addresses mapped to a person. The addresses are keeped in a Set and displayed in a Wicket RefreshingView (with a ReuseIfEquals strategy). I could either use the surrogate id or use all fields in the equals() and hashCode() functions. The problem is that those fields change during the lifetime ob the object. Either because the user entered some data or the id changes due to JPA merge() being called inside the OSIV (Open Session in View) filter. My understanding of the equals() and hashCode() contract is that those should not change during the lifetime of an object. What i have tried so far: equals() based on hashCode() which uses the database id (or super.hashCode() if id is null). Problem: new addresses start with an null id but get an id when attached to a person and this person gets merged() (re-attached) in the osiv-filter. lazy compute the hashcode when hashCode() is first called and make that hashcode @Transitional. Does not work, as merge() returns a new object and the hashcode does not get copied over. What i would need is an ID that gets assigned during object creation I think. What would be my options here? I don't want to introduce some additional persistent property. Is there a way to explicitly tell JPA to assign an ID to an object? Regards

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  • How to return a record from function, executed by INSERT/UPDATE rule (trigger)?

    - by seas
    Do the following scheme for my database: create sequence data_sequence; create table data_table { id integer primary key; field varchar(100); }; create view data_view as select id, field from data_table; create function data_insert(_new data_view) returns data_view as $$declare _id integer; _result data_view%rowtype; begin _id := nextval('data_sequence'); insert into data_table(id, field) values(_id, _new.field); select * into _result from data_view where id = _id; return _result; end; $$ language plpgsql; create rule insert as on insert to data_view do instead select data_insert(new); Then type in psql: insert into data_view(field) values('abc'); Would like to see something like: id | field ----+--------- 1 | abc Instead see: data_insert ------------- (1, "abc") Is it possible to fix this somehow? Thanks for any ideas. Ultimate idea is to use this in other functions, so that I could obtain id of just inserted record without selecting for it from scratch. Something like: insert into data_view(field) values('abc') returning id into my_variable would be nice but doesn't work with error: ERROR: cannot perform INSERT RETURNING on relation "data_view" HINT: You need an unconditional ON INSERT DO INSTEAD rule with a RETURNING clause. I don't really understand that HINT. I use PostgreSQL 8.4.

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  • Magento: Attribute always returns default value in catalog view, works fine in product view

    - by colinodell
    I've created a new Yes/No attribute for products. I've extended the Product model to do some custom logic and the custom functions are working everywhere. When I initially tried getting the custom attribute value, I ran into some issue. Magento wasn't loading it for me, so calls to $product-getMyAttributeName() did nothing. In the product views, I got it working with this additional function: public function getAttrVal($attr_name) { return $this->getResource()->getAttribute($attr_name)->getFrontend()->getValue($this); } So that worked great when viewing a product on the frontend. It would fetch the assigned value if set, or the default if not. When I view any Category (grid of all products in that category), the same exact code is being executed. But my getAttrVal() function always returns the default value, even if I've explicitly set this value for my product. I can't, for the life of me, figure out why the attribute loads correctly in the Product view but the Category view always grabs the default value, despite running the same exact code. Any thoughts?

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