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  • c++ compile error

    - by Niranjan
    Hi, I am trying to develop abstract design pattern code for one of my project as below.. But, I am not able to compile the code ..giving some compile errors(like "conversion from 'ProductA1 *' to 'ProductA *' exists, but is inaccessible" ).. Can any one please help me out in this... #include "stdafx.h" #include <iostream> using namespace std; class ProductA { public: virtual void Operation1()=0; virtual void Operation2()=0; }; class ProductA1 : ProductA { public: virtual void Operation1() {cout<<"PD ProductA1 Operation1"<<endl; } virtual void Operation2() {cout<<"PD ProductA1 Operation2"<<endl; } }; class ProductA2 : ProductA { public: virtual void Operation1() {cout<<"DT ProductA2 Operation1"<<endl; } virtual void Operation2() {cout<<"DT ProductA2 Operation2"<<endl; } }; //------------------------------------------------------------- class ProductB { public: virtual void Operation3()=0; virtual void Operation4()=0; }; class ProductB1 : ProductB { public: void Operation3() { cout<<"PD ProductB1 Operation3"<<endl; } void Operation4() { cout<<"PD ProductB1 Operation4"<<endl; } }; class ProductB2 : ProductB { public: void Operation3() { cout<<"DT ProductB2 Operation3"<<endl; } void Operation4() { cout<<"DT ProductB2 Operation4"<<endl; } }; //--------------- abstrct factory --------------------------- class Factory { public: virtual ProductA* CreateA () =0; virtual ProductB* CreateB ()=0; }; class Factory1 : Factory { public: ProductA* CreateA () { return new ProductA1(); } ProductB* CreateB () { return new ProductB1(); } }; class Factory2 : Factory { public: ProductA* CreateA () { return new ProductA2(); } ProductB* CreateB () { return new ProductB2(); } }; //--------------------- client -------------------------------- int _tmain(int argc, _TCHAR* argv[]) { Factory* pf = new Factory1(); ProductA *pa = pf->CreateA(); pa->Operation1(); pa->Operation2(); ProductB *pb = pf->CreateB(); pb->Operation3(); pb->Operation4(); return 0; }

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  • Using Core Data Concurrently and Reliably

    - by John Topley
    I'm building my first iOS app, which in theory should be pretty straightforward but I'm having difficulty making it sufficiently bulletproof for me to feel confident submitting it to the App Store. Briefly, the main screen has a table view, upon selecting a row it segues to another table view that displays information relevant for the selected row in a master-detail fashion. The underlying data is retrieved as JSON data from a web service once a day and then cached in a Core Data store. The data previous to that day is deleted to stop the SQLite database file from growing indefinitely. All data persistence operations are performed using Core Data, with an NSFetchedResultsController underpinning the detail table view. The problem I am seeing is that if you switch quickly between the master and detail screens several times whilst fresh data is being retrieved, parsed and saved, the app freezes or crashes completely. There seems to be some sort of race condition, maybe due to Core Data importing data in the background whilst the main thread is trying to perform a fetch, but I'm speculating. I've had trouble capturing any meaningful crash information, usually it's a SIGSEGV deep in the Core Data stack. The table below shows the actual order of events that happen when the detail table view controller is loaded: Main Thread Background Thread viewDidLoad Get JSON data (using AFNetworking) Create child NSManagedObjectContext (MOC) Parse JSON data Insert managed objects in child MOC Save child MOC Post import completion notification Receive import completion notification Save parent MOC Perform fetch and reload table view Delete old managed objects in child MOC Save child MOC Post deletion completion notification Receive deletion completion notification Save parent MOC Once the AFNetworking completion block is triggered when the JSON data has arrived, a nested NSManagedObjectContext is created and passed to an "importer" object that parses the JSON data and saves the objects to the Core Data store. The importer executes using the new performBlock method introduced in iOS 5: NSManagedObjectContext *child = [[NSManagedObjectContext alloc] initWithConcurrencyType:NSPrivateQueueConcurrencyType]; [child setParentContext:self.managedObjectContext]; [child performBlock:^{ // Create importer instance, passing it the child MOC... }]; The importer object observes its own MOC's NSManagedObjectContextDidSaveNotification and then posts its own notification which is observed by the detail table view controller. When this notification is posted the table view controller performs a save on its own (parent) MOC. I use the same basic pattern with a "deleter" object for deleting the old data after the new data for the day has been imported. This occurs asynchronously after the new data has been fetched by the fetched results controller and the detail table view has been reloaded. One thing I am not doing is observing any merge notifications or locking any of the managed object contexts or the persistent store coordinator. Is this something I should be doing? I'm a bit unsure how to architect this all correctly so would appreciate any advice.

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  • C++ - Breaking code implementation into different parts

    - by Kotti
    Hi! The question plot (a bit abstract, but answering this question will help me in my real app): So, I have some abstract superclass for objects that can be rendered on the screen. Let's call it IRenderable. struct IRenderable { // (...) virtual void Render(RenderingInterface& ri) = 0; virtual ~IRenderable() { } }; And suppose I also have some other objects that derive from IRenderable, e.g. Cat and Dog. So far so good. I add some Cat and Dog specific methods, like SeekForWhiskas(...) and Bark(...). After that I add specific Render(...) method for them, so my code looks this way: class Cat : public IRenderable { public: void SeekForWhiskas(...) { // Implementation could be here or moved // to a source file (depends on me wanting // to inline it or not) } virtual void Render(...) { // Here comes the rendering routine, that // is specific for cats SomehowDrawAppropriateCat(...); } }; class Dog : public IRenderable { public: void Bark(...) { // Same as for 'SeekForWhiskas(...)' } virtual void Render(...) { // Here comes the rendering routine, that // is specific for dogs DrawMadDog(...); } }; And then somewhere else I can do drawing the way that an appropriate rendering routine is called: IRenderable* dog = new Dog(); dog->Render(...); My question is about logical wrapping of such kind of code. I want to break apart the code, that corresponds to rendering of the current object and it's own methods (Render and Bark in this example), so that my class implementation doesn't turn into a mess (imagine that I have 10 methods like Bark and of course my Render method doesn't fit in their company and would be hard to find). Two ways of making what I want to (as far as I know) are: Making appropriate routines that look like RenderCat(Cat& cat, RenderInterface* ri), joining them to render namespace and then the functions inside a class would look like virtual void Render(...) { RenderCat(*this, ...); }, but this is plain stupid, because I'll lose access to Cat's private members and friending these functions looks like a total design disaster. Using visitor pattern, but this would also mean I have to rebuild my app's design and looks like an inadequate way to make my code complicated from the very beginning. Any brilliant ideas? :)

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  • C++ game designing & polymorphism question

    - by Kotti
    Hi! I'm trying to implement some sort of 'just-for-me' game engine and the problem's plot goes the following way: Suppose I have some abstract interface for a renderable entity, e.g. IRenderable. And it's declared the following way: interface IRenderable { // (...) // Suppose that Backend is some abstract backend used // for rendering, and it's implementation is not important virtual void Render(Backend& backend) = 0; }; What I'm doing right now is something like declaring different classes like class Ball : public IRenderable { virtual void Render(Backend& backend) { // Rendering implementation, that is specific for // the Ball object // (...) } }; And then everything looks fine. I can easily do something like std::vector<IRenderable*> items, push some items like new Ball() in this vector and then make a call similiar to foreach (IRenderable* in items) { item->Render(backend); } Ok, I guess it is the 'polymorphic' way, but what if I want to have different types of objects in my game and an ability to manipulate their state, where every object can be manipulated via it's own interface? I could do something like struct GameState { Ball ball; Bonus bonus; // (...) }; and then easily change objects state via their own methods, like ball.Move(...) or bonus.Activate(...), where Move(...) is specific for only Ball and Activate(...) - for only Bonus instances. But in this case I lose the opportunity to write foreach IRenderable* simply because I store these balls and bonuses as instances of their derived, not base classes. And in this case the rendering procedure turns into a mess like ball.Render(backend); bonus.Render(backend); // (...) and it is bad because we actually lose our polymorphism this way (no actual need for making Render function virtual, etc. The other approach means invoking downcasting via dynamic_cast or something with typeid to determine the type of object you want to manipulate and this looks even worse to me and this also breaks this 'polymorphic' idea. So, my question is - is there some kind of (probably) alternative approach to what I want to do or can my current pattern be somehow modified so that I would actually store IRenderable* for my game objects (so that I can invoke virtual Render method on each of them) while preserving the ability to easily change the state of these objects? Maybe I'm doing something absolutely wrong from the beginning, if so, please point it out :) Thanks in advance!

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  • What is the best way to return two values from a method?

    - by Edward Tanguay
    When I have to write methods which return two values, I usually go about it as in the following code which returns a List<string>. Or if I have to return e.g. a id and string, then I return a List<object> and then pick them out with index number and recast the values. This recasting and referencing by index seems inelegant so I want to develop a new habit for methods that return two values. What is the best pattern for this? using System; using System.Collections.Generic; using System.Linq; namespace MultipleReturns { class Program { static void Main(string[] args) { string extension = "txt"; { List<string> entries = GetIdCodeAndFileName("first.txt", extension); Console.WriteLine("{0}, {1}", entries[0], entries[1]); } { List<string> entries = GetIdCodeAndFileName("first", extension); Console.WriteLine("{0}, {1}", entries[0], entries[1]); } Console.ReadLine(); } /// <summary> /// gets "first.txt", "txt" and returns "first", "first.txt" /// gets "first", "txt" and returns "first", "first.txt" /// it is assumed that extensions will always match /// </summary> /// <param name="line"></param> public static List<string> GetIdCodeAndFileName(string line, string extension) { if (line.Contains(".")) { List<string> parts = line.BreakIntoParts("."); List<string> returnItems = new List<string>(); returnItems.Add(parts[0]); returnItems.Add(line); return returnItems; } else { List<string> returnItems = new List<string>(); returnItems.Add(line); returnItems.Add(line + "." + extension); return returnItems; } } } public static class StringHelpers { public static List<string> BreakIntoParts(this string line, string separator) { if (String.IsNullOrEmpty(line)) return null; else { return line.Split(new string[] { separator }, StringSplitOptions.None).Select(p => p.Trim()).ToList(); } } } }

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  • Do you use an exception class in your Perl programs? Why or why not?

    - by daotoad
    I've got a bunch of questions about how people use exceptions in Perl. I've included some background notes on exceptions, skip this if you want, but please take a moment to read the questions and respond to them. Thanks. Background on Perl Exceptions Perl has a very basic built-in exception system that provides a spring-board for more sophisticated usage. For example die "I ate a bug.\n"; throws an exception with a string assigned to $@. You can also throw an object, instead of a string: die BadBug->new('I ate a bug.'); You can even install a signal handler to catch the SIGDIE psuedo-signal. Here's a handler that rethrows exceptions as objects if they aren't already. $SIG{__DIE__} = sub { my $e = shift; $e = ExceptionObject->new( $e ) unless blessed $e; die $e; } This pattern is used in a number of CPAN modules. but perlvar says: Due to an implementation glitch, the $SIG{DIE} hook is called even inside an eval(). Do not use this to rewrite a pending exception in $@ , or as a bizarre substitute for overriding CORE::GLOBAL::die() . This strange action at a distance may be fixed in a future release so that $SIG{DIE} is only called if your program is about to exit, as was the original intent. Any other use is deprecated. So now I wonder if objectifying exceptions in sigdie is evil. The Questions Do you use exception objects? If so, which one and why? If not, why not? If you don't use exception objects, what would entice you to use them? If you do use exception objects, what do you hate about them, and what could be better? Is objectifying exceptions in the DIE handler a bad idea? Where should I objectify my exceptions? In my eval{} wrapper? In a sigdie handler? Are there any papers, articles or other resources on exceptions in general and in Perl that you find useful or enlightening.

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  • Robust way to save/load objects with dependencies?

    - by mrteacup
    I'm writing an Android game in Java and I need a robust way to save and load application state quickly. The question seems to apply to most OO languages. To understand what I need to save: I'm using a Strategy pattern to control my game entities. The idea is I have a very general Entity class which e.g. stores the location of a bullet/player/enemy and I then attach a Behaviour class that tells the entity how to act: class Entiy { float x; float y; Behavior b; } abstract class Behavior { void update(Entity e); {} // Move about at a constant speed class MoveBehavior extends Behavior { float speed; void update ... } // Chase after another entity class ChaseBehavior extends Behavior { Entity target; void update ... } // Perform two behaviours in sequence class CombineBehavior extends Behavior { Behaviour a, b; void update ... } Essentially, Entity objects are easy to save but Behaviour objects can have a semi-complex graph of dependencies between other Entity objects and other Behaviour objects. I also have cases where a Behaviour object is shared between entities. I'm willing to change my design to make saving/loading state easier, but the above design works really well for structuring the game. Anyway, the options I've considered are: Use Java serialization. This is meant to be really slow in Android (I'll profile it sometime). I'm worried about robustness when changes are made between versions however. Use something like JSON or XML. I'm not sure how I would cope with storing the dependencies between objects however. Would I have to give each object a unique ID and then use these IDs on loading to link the right objects together? I thought I could e.g. change the ChaseBehaviour to store a ID to an entity, instead of a reference, that would be used to look up the Entity before performing the behaviour. I'd rather avoid having to write lots of loading/saving code myself as I find it really easy to make mistakes (e.g. forgetting to save something, reading things out in the wrong order). Can anyone give me any tips on good formats to save to or class designs that make saving state easier?

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  • Can I write a test that succeeds if and only if a statement does not compile?

    - by Billy ONeal
    I'd like to prevent clients of my class from doing something stupid. To that end, I have used the type system, and made my class only accept specific types as input. Consider the following example (Not real code, I've left off things like virtual destructors for the sake of example): class MyDataChunk { //Look Ma! Implementation! }; class Sink; class Source { virtual void Run() = 0; Sink *next_; void SetNext(Sink *next) { next_ = next; } }; class Sink { virtual void GiveMeAChunk(const MyDataChunk& data) { //Impl }; }; class In { virtual void Run { //Impl } }; class Out { }; //Note how filter and sorter have the same declaration. Concrete classes //will inherit from them. The seperate names are there to ensure only //that some idiot doesn't go in and put in a filter where someone expects //a sorter, etc. class Filter : public Source, public Sink { //Drop objects from the chain-of-command pattern that don't match a particular //criterion. }; class Sorter : public Source, public Sink { //Sorts inputs to outputs. There are different sorters because someone might //want to sort by filename, size, date, etc... }; class MyClass { In i; Out o; Filter f; Sorter s; public: //Functions to set i, o, f, and s void Execute() { i.SetNext(f); f.SetNext(s); s.SetNext(o); i.Run(); } }; What I don't want is for somebody to come back later and go, "Hey, look! Sorter and Filter have the same signature. I can make a common one that does both!", thus breaking the semantic difference MyClass requires. Is this a common kind of requirement, and if so, how might I implement a test for it?

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  • Read from file in eclipse

    - by Buzkie
    I'm trying to read from a text file to input data to my java program. However, eclipse continuosly gives me a Source not found error no matter where I put the file. I've made an additional sources folder in the project directory, the file in question is in both it and the bin file for the project and it still can't find it. I even put a copy of it on my desktop and tried pointing eclipse there when it asked me to browse for the source lookup path. No matter what I do it can't find the file. here's my code in case it's pertinent: System.out.println(System.getProperty("user.dir")); File file = new File("file.txt"); Scanner scanner = new Scanner(file); in addition, it says the user directory is the project directory and there is a copy there too. I have no clue what to do. Thanks, Alex after attempting the suggestion below and refreshing again, I was greeted by a host of errors. FileNotFoundException(Throwable).<init>(String) line: 195 FileNotFoundException(Exception).<init>(String) line: not available FileNotFoundException(IOException).<init>(String) line: not available FileNotFoundException.<init>(String) line: not available URLClassPath$JarLoader.getJarFile(URL) line: not available URLClassPath$JarLoader.access$600(URLClassPath$JarLoader, URL) line: not available URLClassPath$JarLoader$1.run() line: not available AccessController.doPrivileged(PrivilegedExceptionAction<T>) line: not available [native method] URLClassPath$JarLoader.ensureOpen() line: not available URLClassPath$JarLoader.<init>(URL, URLStreamHandler, HashMap) line: not available URLClassPath$3.run() line: not available AccessController.doPrivileged(PrivilegedExceptionAction<T>) line: not available [native method] URLClassPath.getLoader(URL) line: not available URLClassPath.getLoader(int) line: not available URLClassPath.access$000(URLClassPath, int) line: not available URLClassPath$2.next() line: not available URLClassPath$2.hasMoreElements() line: not available ClassLoader$2.hasMoreElements() line: not available CompoundEnumeration<E>.next() line: not available CompoundEnumeration<E>.hasMoreElements() line: not available ServiceLoader$LazyIterator.hasNext() line: not available ServiceLoader$1.hasNext() line: not available LocaleServiceProviderPool$1.run() line: not available AccessController.doPrivileged(PrivilegedExceptionAction<T>) line: not available [native method] LocaleServiceProviderPool.<init>(Class<LocaleServiceProvider>) line: not available LocaleServiceProviderPool.getPool(Class<LocaleServiceProvider>) line: not available NumberFormat.getInstance(Locale, int) line: not available NumberFormat.getNumberInstance(Locale) line: not available Scanner.useLocale(Locale) line: not available Scanner.<init>(Readable, Pattern) line: not available Scanner.<init>(ReadableByteChannel) line: not available Scanner.<init>(File) line: not available code used: System.out.println(System.getProperty("user.dir")); File file = new File(System.getProperty("user.dir") + "/file.txt"); Scanner scanner = new Scanner(file);

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  • cakephp datetime insertion behaviour

    - by littlechad
    hi everyone this is a cakePHP question about datetime database insertion mismatch, i jumped in to this project while the whole thing is already built around 70%. here's what happen, every time i insert a data that contain a datetime, the inserted time doesn't match the inputted date, and the mismatch has no pattern or what ever, in some table the differences is 5 hours, while in others it could be 12 hours, 7 hours, or even 15 hours. i have traced this by investigating the controller, the model, the app_controller, everything but i don't find anything that indicate a datetime insertion rules. if the view : echo $form->input('start_date', array('label' => __l('start date')); i can't even find in the controller anything like: $this->data['current_controller']['start_date'] = $this->data['current_controller']['start_date']; when i use pr($this-data); to print the posted data, this is shown: [start_date] => Array ( [month] => 02 [day] => 16 [year] => 2011 [hour] => [min] => [meridian] => ) so i figured doing something like: $yearMonDay = $this->data['current_controller']['start_date']['year']."-"; $yearMonDay .= $this->data['current_controller']['start_date']['month']."-"; $yearMonDay .= $this->data['current_controller']['start_date']['day']; if(!empty($this->data['current_controller']['start_date']['hour'])){ $hourMinSec = $this->data['current_controller']['start_date']['hour'].":"; $hourMinSec .= $this->data['current_controller']['start_date']['min'].":"; $hourMinSec .= $this->data['current_controller']['start_date']['meridian']; }else{ $hourMinSec = "00:00:00"; } $this->data['Deal']['start_date'] = $yearMonDay." ".$hourMinSec; just to make sure the funny thing is that those posted datetime is inserted into the database with the mismatch value anyway. it's getting pretty frustrating, is there any suggestion on where else should i find the codes that define how the datetime should be inserted? or probably give me a clue on how to override those mismatched insertion rules? thanks

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  • php regex guitar tab (tabs or tablature, a type of music notation)

    - by John
    I am in the process of creating a guitar tab to rtttl (Ring Tone Text Transfer Language) converter in PHP. In order to prepare a guitar tab for rtttl conversion I first strip out all comments (comments noted by #- and ended with -#), I then have a few lines that set tempo, note the tunning and define multiple instruments (Tempo 120\nDefine Guitar 1\nDefine Bass 1, etc etc) which are stripped out of the tab and set aside for later use. Now I essentially have nothing left except the guitar tabs. Each tab is prefixed with it's instrument name in conjunction with the instrument name noted prior. Some times we have tabs for 2 separate instruments that are linked because they are to be played together, ie a Guitar and a Bass Guitar playing together. Example 1, Standard Guitar Tab: |Guitar 1 e|--------------3-------------------3------------| B|------------3---3---------------3---3----------| G|----------0-------0-----------0-------0--------| D|--------0-----------0-------0-----------0------| A|------2---------------2---2---------------2----| E|----3-------------------3-------------------3--| Example 2, Conjunction Tab: |Guitar 1 e|--------------3-------------------3------------| B|------------3---3---------------3---3----------| G|----------0-------0-----------0-------0--------| D|--------0-----------0-------0-----------0------| A|------2---------------2---2---------------2----| E|----3-------------------3-------------------3--| | | |Bass 1 G|----------0-------0-----------0-------0--------| D|--------2-----------2-------2-----------2------| A|------3---------------3---3---------------3----| E|----3-------------------3-------------------3--| I have considered other methods of identifying the tabs with no solid results. I am hoping that someone who does regular expressions could help me find a way to identify a single guitar tab and if possible also be able to match a tab with multiple instruments linked together. Once the tabs are in an array I will go through them one line at a time and convert them into rtttl lines (exploded at each new line "\n"). I do not want to separate the guitar tabs in the document via explode "\n\n" or something similar because it does not identify the guitar tab, rather, it is identifying the space between the tabs - not on the tabs themselves. I have been messing with this for about a week now and this is the only major hold up I have. Everything else is fairly simple. As of current, I have tried many variations of the regex pattern. Here is one of the most recent test samples: <?php $t = " |Guitar 1 e|--------------3-------------------3------------| B|------------3---3---------------3---3----------| G|----------0-------0-----------0-------0--------| D|--------0-----------0-------0-----------0------| A|------2---------------2---2---------------2----| E|----3-------------------3-------------------3--| |Guitar 1 e|--------------3-------------------3------------| B|------------3---3---------------3---3----------| G|----------0-------0-----------0-------0--------| D|--------0-----------0-------0-----------0------| A|------2---------------2---2---------------2----| E|----3-------------------3-------------------3--| | | |Bass 1 G|----------0-------0-----------0-------0--------| D|--------2-----------2-------2-----------2------| A|------3---------------3---3---------------3----| E|----3-------------------3-------------------3--| "; preg_match_all("/^.*?(\\|).*?(\\|)/is",$t,$p); print_r($p); ?> It is also worth noting that inside the tabs, where the dashes and #'s are, you may also have any variation of letters, numbers and punctuation. The beginning of each line marks the tuning of each string with one of the following case insensitive: a,a#,b,c,c#,d,d#,e,f,f#,g or g. Thanks in advance for help with this most difficult problem.

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  • Separation of domain and ui layer in a composite

    - by hansmaad
    Hi all, i'm wondering if there is a pattern how to separate the domain logic of a class from the ui responsibilities of the objects in the domain layer. Example: // Domain classes interface MachinePart { CalculateX(in, out) // Where do we put these: // Draw(Screen) ?? // ShowProperties(View) ?? // ... } class Assembly : MachinePart { CalculateX(in, out) subParts } class Pipe : MachinePart { CalculateX(in, out) length, diamater... } There is an application that calculates the value X for machines assembled from many machine parts. The assembly is loaded from a file representation and is designed as a composite. Each concrete part class stores some data to implement the CalculateX(in,out) method to simulate behaviour of the whole assembly. The application runs well but without GUI. To increase the usability a GUi should be developed on top of the existing implementation (changes to the existing code are allowed). The GUI should show a schematic graphical representation of the assembly and provide part specific dialogs to edit several parameters. To achieve these goals the application needs new functionality for each machine part to draw a schematic representation on the screen, show a property dialog and other things not related to the domain of machine simulation. I can think of some different solutions to implement a Draw(Screen) functionality for each part but i am not happy with each of them. First i could add a Draw(Screen) method to the MachinePart interface but this would mix-up domain code with ui code and i had to add a lot of functionality to each machine part class what makes my domain model hard to read and hard to understand. Another "simple" solution is to make all parts visitable and implement ui code in visitors but Visitor does not belong to my favorite patterns. I could derive UI variants from each machine part class to add the UI implementation there but i had to check if each part class is suited for inheritance and had to be careful on changes to the base classes. My currently favorite design is to create a parallel composite hierarchy where each component stores data to define a machine part, has implementation for UI methods and a factory method which creates instances of the corresponding domain classes, so that i can "convert" a UI assembly to a domain assembly. But there are problems to go back from the created domain hierarchy to the UI hierarchy for showing calculation results in the drawing for example (imagine some parts store some values during the calculation i want to show in the schematic representation after the simluation). Maybe there are some proven patterns for such problems?

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  • How do make dependency generation work for C? (Also..decode this sed/make statement!)

    - by Derek
    Hi all. I have a make build system that I am trying to decipher that someone else wrote. I am getting an error when I run it on a redhat system, but not when I run it on my solaris system. The versions of gmake are the same major revision (one off on minor revision). This is for building a C project, and the make system has a global Makefile.global that is inherited by each directory's local Makefile The Makefile.global has all the targets in it, starting with all: $(LIB) $(BIN) where LIB builds libs and BIN builds binaries. jumping down the targets I have $(LIB) : $(GEN_LIB) $(GEN_LIB) : $(GEN_DEPS) $(GEN_OBJS) $(AR) $(ARFLAGS) $(GEN_LIB) $(GEN_OBJS) $(GEN_DEPS) : @set -e; rm -f $@; \ $(CC) $(CDEP_FLAG) $(CFLAGS) $(INCDIRS) `basename $@ | sed 's/\.d/\.c/' | sed 's,^,$(HOME_SRC)/,'` | sed 's,\(.*\)\.o: ,$(GEN_OBJDIR)/\1.o $@ :,g' > [email protected] ; \ cat [email protected] > $@ ; \ cat [email protected] | cut -d: -f2 | grep '\.h' | sed 's,\.h,.h :,g' >> $@ ; \ rm [email protected] $(GEN_OBJS) : $(CC) $(CFLAGS) $(INCDIRS) -c $(*F).c -lmpi -o $@ I think these are all the relevant targets I need to include to answer my question. Definitions of those variables: CC = icc CDEP_FLAG = -M CFLAGS = various compiler flags ifdef type flags INCDIRS = include directory where all .h files are GEN_OBJDIR = /lib/objs HOME_SRC = . GEN_LIB = lib/$(LIB) GEN_DEPDIR=/lib/deps GEN_DEPS = $(addprefix $(GEN_DEPDIR)/,$(addsuffix .d,$(basename $(OBJS)))) I think this has everything covered you need. Basically self explanatory from the names. Now as best I can tell, this is generating in /lib/deps a .d file that has the object and source dependencies in it. In other words, for the utilities.a library, I will get a utils.o and utils.c dependency stack, all in the file utils.d There is some syntax error that is being generated in that file I think, because I get the following error: ../lib/deps/util.d:25: *** target pattern contains no '%'. Stop. gmake[2]: *** [all] Error 2 gmake[1]: *** [all] Error 2 gmake: *** [all] Error 2 I am not sure if my error is in the dependency generation, or some further down part, like the object generation target? If you need further info, let me know, I will add to post

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  • Persistence scheme & state data for low memory situations (iphone)

    - by Robin Jamieson
    What happens to state information held by a class's variable after coming back from a low memory situation? I know that views will get unloaded and then reloaded later but what about some ancillary classes & data held in them that's used by the controller that launched the view? Sample scenario in question: @interface MyCustomController: UIViewController { ServiceAuthenticator *authenticator; } -(id)initWithAuthenticator:(ServiceAuthenticator *)auth; // the user may press a button that will cause the authenticator // to post some data to the service. -(IBAction)doStuffButtonPressed:(id)sender; @end @interface ServiceAuthenticator { BOOL hasValidCredentials; // YES if user's credentials have been validated NSString *username; NSString *password; // password is not stored in plain text } -(id)initWithUserCredentials:(NSString *)username password:(NSString *)aPassword; -(void)postData:(NSString *)data; @end The app delegate creates the ServiceAuthenticator class with some user data (read from plist file) and the class logs the user with the remote service. inside MyAppDelegate's applicationDidFinishLaunching: - (void)applicationDidFinishLaunching:(UIApplication *)application { ServiceAuthenticator *auth = [[ServiceAuthenticator alloc] initWithUserCredentials:username password:userPassword]; MyCustomController *controller = [[MyCustomController alloc] initWithNibName:...]; controller.authenticator = auth; // Configure and show the window [window addSubview:..]; // make everything visible [window makeKeyAndVisible]; } Then whenever the user presses a certain button, 'MyCustomController's doStuffButtonPressed' is invoked. -(IBAction)doStuffButtonPressed:(id)sender { [authenticator postData:someDataFromSender]; } The authenticator in-turn checks to if the user is logged in (BOOL variable indicates login state) and if so, exchanges data with the remote service. The ServiceAuthenticator is the kind of class that validates the user's credentials only once and all subsequent calls to the object will be to postData. Once a low memory scenario occurs and the associated nib & MyCustomController will get unloaded -- when it's reloaded, what's the process for resetting up the 'ServiceAuthenticator' class & its former state? I'm periodically persisting all of the data in my actual model classes. Should I consider also persisting the state data in these utility style classes? Is that the pattern to follow?

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  • Architecture Suggestions/Recommendations for a Web Application with Sub-Apps

    - by user579218
    Hello. I’m starting to plan an architecture for a big web application, and I wanted to get suggestions and/or recommendations on where to begin and which technologies and/or frameworks to use. The application will be an Intranet-based web site using Windows authentication, running on IIS and using SQL Server and ASP.NET. It’ll need to be structured as a main/shell application with sub-applications that are “pluggable” based on some configuration settings. The main or shell application is to provide the overall user interface structure – header/footer, dynamically built tabs for each available sub-app, and a content area in which the sub-application will be loaded when the user clicks on the sub-application’s tab. So, on start-up of the main/shell application, configuration information will be queried from a database, and, based on the user and which of the sub-apps are available, the main or shell app would dynamically build tabs (or buttons or something) as a way to access each individual application. On start-up, the content area will be populated with the “home” sub-app. But, clicking on an sub-app tab will cause the content area to be populated with the sub-app corresponding to the tab. For example, we’re going to have a reports application, a display application, and probably a couple other distinct applications. On startup of the main/shell application, after determining who the user is, the main app will query the database to determine which sub-apps the user can use and build out the UI. Then the user can navigate between available sub-apps and do their work in each. Finally, the entire app and all sub-apps need to be a layered design with presentation, service, business, and data access layers, as well as cross-cutting objects for things such as logging, exception handling, etc. Anyway, my questions revolve around where to begin to plan something like this application. What technologies/frameworks would work best in developing a solution for this application? MVC? MVP? WCSF? EF? NHibernate? Enterprise Library? Repository Pattern? Others???? I know all these technologies/frameworks are not used for the same purpose, but knowing which ones to focus on is a little overwhelming. Which ones would be the best choice(s) for a solution? Which ones work well together for an end-to-end design? How would one structure the VS project for something like this? Thanks!

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  • JavaScript (via Greasemonkey) failing to set "title" attributes on <a> tags

    - by rjray
    I have the following (fairly) simple JavaScript snippet that I have wired into Greasemonkey. It goes through a page, looks for <a> tags whose href points to tinyurl.com, and adds a "title" attribute that identifies the true destination of the link. Much of the important code comes from an older (unsupported) Greasemonkey script that quits working when the inner component that held the XPath implementation changed. My script: (function() { var providers = new Array(); providers['tinyurl.com'] = function(link, fragment) { // This is mostly taken from the (broken due to XPath component // issues) tinyurl_popup_preview script. link.title = "Loading..."; GM_xmlhttpRequest({ method: 'GET', url: 'http://preview.tinyurl.com/' + fragment, onload: function(res) { var re = res.responseText.match("<blockquote><b>(.+)</b></blockquote>"); if (re) { link.title = re[1].replace(/\<br \/\>/g, "").replace(/&amp;/g, "&"); } else { link.title = "Parsing failed..."; } }, onerror: function() { link.title = "Connection failed..."; } }); }; var uriPattern = /(tinyurl\.com)\/([a-zA-Z0-9]+)/; var aTags = document.getElementsByTagName("a"); for (i = 0; i < aTags.length; i++) { var data = aTags[i].href.match(uriPattern); if (data != null && data.length > 1 && data[2] != "preview") { var source = data[1]; var fragment = data[2]; var link = aTags[i]; aTags[i].addEventListener("mouseover", function() { if (link.title == "") { (providers[source])(link, fragment); } }, false); } } })(); (The reason the "providers" associative array is set up the way it is, is so that I can expand this to cover other URL-shortening services as well.) I have verified that all the various branches of code are being reached correctly, in cases where the link being examined does and does not match the pattern. What isn't happening, is any change to the "title" attribute of the anchor tags. I've watched this via Firebug, thrown alert() calls in left and right, and it just never changes. In a previous iteration all expressions of the form: link.title = "..."; had originally been: link.setAttribute("title", "..."); That didn't work, either. I'm no newbie to JavaScript OR Greasemonkey, but this one has me stumped!

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  • Subclassing and adding data members

    - by Marius
    I have an hierarchy of classes that looks like the following: class Critical { public: Critical(int a, int b) : m_a(a), m_b(b) { } virtual ~Critical() { } int GetA() { return m_a; } int GetB() { return m_b; } void SetA(int a) { m_a = a; } void SetB(int b) { m_b = b; } protected: int m_a; int m_b; }; class CriticalFlavor : public Critical { public: CriticalFlavor(int a, int b, int flavor) : Critical(a, b), m_flavor(flavor) { } virtual ~CriticalFlavor() { } int GetFlavor() { return m_flavor; } void SetFlavor(int flavor) { m_flavor = flavor; } protected: int m_flavor; }; class CriticalTwist : public Critical { public: CriticalTwist(int a, int b, int twist) : Critical(a, b), m_twist(twist) { } virtual ~CriticalTwist() { } int GetTwist() { return m_twist; } void SetTwist(int twist) { m_twist = twist; } protected: int m_twist; }; The above does not seem right to me in terms of the design and what bothers me the most is the fact that the addition of member variables seems to drive the interface of these classes (the real code that does the above is a little more complex but still embracing the same pattern). That will proliferate when in need for another "Critical" class that just adds some other property. Does this feel right to you? How could I refactor such code? An idea would be to have just a set of interfaces and use composition when it comes to the base object like the following: class Critical { public: virtual int GetA() = 0; virtual int GetB() = 0; virtual void SetA(int a) = 0; virtual void SetB(int b) = 0; }; class CriticalImpl { public: CriticalImpl(int a, int b) : m_a(a), m_b(b) { } ~CriticalImpl() { } int GetA() { return m_a; } int GetB() { return m_b; } void SetA(int a) { m_a = a; } void SetB(int b) { m_b = b; } private: int m_a; int m_b; }; class CriticalFlavor { public: virtual int GetFlavor() = 0; virtual void SetFlavor(int flavor) = 0; }; class CriticalFlavorImpl : public Critical, public CriticalFlavor { public: CriticalFlavorImpl(int a, int b, int flavor) : m_flavor(flavor), m_critical(new CriticalImpl(a, b)) { } ~CriticalFlavorImpl() { delete m_critical; } int GetFlavor() { return m_flavor; } void SetFlavor(int flavor) { m_flavor = flavor; } int GetA() { return m_critical-GetA(); } int GetB() { return m_critical-GetB(); } void SetA(int a) { m_critical-SetA(a); } void SetB(int b) { m_critical-SetB(b); } private: int m_flavor; CriticalImpl* m_critical; };

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  • I am getting the below mentioned error in my program. what will be the solution?

    - by suvirai
    // Finaldesktop.cpp : Defines the entry point for the console application. // include include include include include using namespace std; int SearchDirectory(vector &refvecFiles, const string &refcstrRootDirectory, const string &refcstrExtension, bool bSearchSubdirectories = true) { string strFilePath; // Filepath string strPattern; // Pattern string strExtension; // Extension HANDLE hFile; // Handle to file WIN32_FIND_DATA FileInformation; // File information strPattern = refcstrRootDirectory + "\."; hFile = FindFirstFile(strPattern.c_str(), &FileInformation); if(hFile != INVALID_HANDLE_VALUE) { do { if(FileInformation.cFileName[0] != '.') { strFilePath.erase(); strFilePath = refcstrRootDirectory + "\" + FileInformation.cFileName; if(FileInformation.dwFileAttributes & FILE_ATTRIBUTE_DIRECTORY) { if(bSearchSubdirectories) { // Search subdirectory int iRC = SearchDirectory(refvecFiles, strFilePath, refcstrExtension, bSearchSubdirectories); if(iRC) return iRC; } } else { // Check extension strExtension = FileInformation.cFileName; strExtension = strExtension.substr(strExtension.rfind(".") + 1); if(strExtension == refcstrExtension) { // Save filename refvecFiles.push_back(strFilePath); } } } } while(FindNextFile(hFile, &FileInformation) == TRUE); // Close handle FindClose(hFile); DWORD dwError = GetLastError(); if(dwError != ERROR_NO_MORE_FILES) return dwError; } return 0; } int main() { int iRC = 0; vector vecAviFiles; vector vecTxtFiles; // Search 'c:' for '.avi' files including subdirectories iRC = SearchDirectory(vecAviFiles, "c:", "avi"); if(iRC) { cout << "Error " << iRC << endl; return -1; } // Print results for(vector::iterator iterAvi = vecAviFiles.begin(); iterAvi != vecAviFiles.end(); ++iterAvi) cout << *iterAvi << endl; // Search 'c:\textfiles' for '.txt' files excluding subdirectories iRC = SearchDirectory(vecTxtFiles, "c:\textfiles", "txt", false); if(iRC) { cout << "Error " << iRC << endl; return -1; } // Print results for(vector::iterator iterTxt = vecTxtFiles.begin(); iterTxt != vecTxtFiles.end(); ++iterTxt) cout << *iterTxt << endl; // Wait for keystroke _getch(); return 0; }

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  • Why does JAXB not create a member variable in its generated code when an XML schema base type and subtype have the same element declared in them?

    - by belltower
    I have a question regarding with regard to JAXB generated classes. As you can I see, I have a complex type, DG_PaymentIdentification1, declared in my schema. Its a restriction of PaymentIdentification1. DG_PaymentIdentification1 is also identical to PaymentIdentification1. I also have a type called DG_CreditTransferTransactionInformation10 which has a base type of CreditTransferTransactionInformation10 and is identical to it. I have included the relevant XML schema snippets below. <xs:complexType name="DG_PaymentIdentification1"> <xs:complexContent> <xs:restriction base="PaymentIdentification1"> <xs:sequence> <xs:element name="InstrId" type="DG_Max35Text_REF" minOccurs="0"/> <xs:element name="EndToEndId" type="DG_Max35Text_REF" id="DG-41"/> </xs:sequence> </xs:restriction> </xs:complexContent> </xs:complexType> <xs:complexType name="PaymentIdentification1"> <xs:sequence> <xs:element name="InstrId" type="Max35Text" minOccurs="0"/> <xs:element name="EndToEndId" type="Max35Text"/> </xs:sequence> </xs:complexType> <xs:complexType name="DG_CreditTransferTransactionInformation10"> <xs:complexContent> <xs:restriction base="CreditTransferTransactionInformation10"> <xs:sequence> <xs:element name="PmtId" type="DG_PaymentIdentification1"/> <xs:simpleType name="DG_Max35Text_REF"> <xs:restriction base="DG_NotEmpty35"> <xs:pattern value="[\-A-Za-z0-9\+/\?:\(\)\.,'&#x20;]*"/> </xs:restriction> </xs:simpleType> <xs:simpleType name="Max35Text"> <xs:restriction base="xs:string"> <xs:minLength value="1"/> <xs:maxLength value="35"/> </xs:restriction> </xs:simpleType> JAXB generates the following java class for DG_PaymentIdentification1: @XmlAccessorType(XmlAccessType.FIELD) @XmlType(name = "DG_CreditTransferTransactionInformDGion10") public class DGCreditTransferTransactionInformation10 extends CreditTransferTransactionInformation10 { } My question is why doesnt the DGCreditTransferTransactionInformation10 generated class have a variable of type DG_PaymentIdentification1 in the generated code? The base class CreditTransferTransactionInformation10 does have a type PaymentIdentification1 declared in it. Is there any way of ensuring that DGCreditTransferTransactionInformation10 will have a DG_PaymentIdentification1 in it?

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  • JavaScript - Inheritance in Constructors

    - by j0ker
    For a JavaScript project we want to introduce object inheritance to decrease code duplication. However, I cannot quite get it working the way I want and need some help. We use the module pattern. Suppose there is a super element: a.namespace('a.elements.Element'); a.elements.Element = (function() { // public API -- constructor Element = function(properties) { this.id = properties.id; }; // public API -- prototype Element.prototype = { getID: function() { return this.id; } }; return Element; }()); And an element inheriting from this super element: a.namespace('a.elements.SubElement'); a.elements.SubElement = (function() { // public API -- constructor SubElement = function(properties) { // inheritance happens here // ??? this.color = properties.color; this.bogus = this.id + 1; }; // public API -- prototype SubElement.prototype = { getColor: function() { return this.color; } }; return SubElement; }()); You will notice that I'm not quite sure how to implement the inheritance itself. In the constructor I have to be able to pass the parameter to the super object constructor and create a super element that is then used to create the inherited one. I need a (comfortable) possibility to access the properties of the super object within the constructor of the new object. Ideally I could operate on the super object as if it was part of the new object. I also want to be able to create a new SubElement and call getID() on it. What I want to accomplish seems like the traditional class based inheritance. However, I'd like to do it using prototypal inheritance since that's the JavaScript way. Is that even doable? Thanks in advance! EDIT: Fixed usage of private variables as suggested in the comments. EDIT2: Another change of the code: It's important that id is accessible from the constructor of SubElement.

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  • PHP Shared Sessions across Domain

    - by bigstylee
    Hi, I have seen a few answers to this on SOO but most of these are concerned with the use of subdomains, of which none have worked for me. The common one being that the use of session.cookie_domain, which from my understanding will only work with subdomains. I am interested in a solution that deals with deals with entirely different domains (and includes the possibility of subdomains). Unfortunately project deadlines being what they are, time is not on my side, so I turn to SOO's expertise and experience. The current project brief is to be able to log into one site which currently only stores the user_id in the session and then be able to retrieve this value while on a different domain within the same server enviroment. Session data is being stored/retrieved from a database where the session id is the primary key. I am hoping to find a "light wieght" and "easy" to implement solution. The system is utlising an in-house Model View Controller design pattern, so all requests (including different domains) are run through a single bootstrap script. Using the domain name as a variable, this determines what context to display to the user. One option that did look like to have potential is the use of a hidden image and using the alt tag to set the user id. My first impressions suggest this immediately seems "too easy" (if possible) and riddled with security flaws. Disscuss? Another option which I considered is using the IP and User Agent for authentication but again I feel this not going to be a reliable option due to shared networks and changing IP addresses. My third option (and preferred) which I considered and as yet not seen discussed is using htaccess to fool the user into thinking that they are on a different domain when infact apache is redirecting; something like www.foo.com/index.php?domain=bar.com&controller=news/categoires/1 but displays to the user as www.bar.com/news/categories/1 foo.com represents the "main site domain" which all requests are run through and bar.com is what the user thinks they are accessing. The controller request dictates the page and view being requested. Is this possible? Are there other options? Pros/Cons? Thanks in advanced!!!

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  • Dynamic swappable Data Access Layer

    - by Andy
    I'm writing a data driven WPF client. The client will typically pull data from a WCF service, which queries a SQL db, but I'd like the option to pull the data directly from SQL or other arbitrary data sources. I've come up with this design and would like to hear your opinion on whether it is the best design. First, we have some data object we'd like to extract from SQL. // The Data Object with a single property public class Customer { private string m_Name = string.Empty; public string Name { get { return m_Name; } set { m_Name = value;} } } Then I plan on using an interface which all data access layers should implement. Suppose one could also use an abstract class. Thoughts? // The interface with a single method interface ICustomerFacade { List<Customer> GetAll(); } One can create a SQL implementation. // Sql Implementation public class SqlCustomrFacade : ICustomerFacade { public List<Customer> GetAll() { // Query SQL db and return something useful // ... return new List<Customer>(); } } We can also create a WCF implementation. The problem with WCF is is that it doesn't use the same data object. It creates its own local version, so we would have to copy the details over somehow. I suppose one could use reflection to copy the values of similar fields across. Thoughts? // Wcf Implementation public class WcfCustomrFacade : ICustomerFacade { public List<Customer> GetAll() { // Get date from the Wcf Service (not defined here) List<WcfService.Customer> wcfCustomers = wcfService.GetAllCustomers(); // The list we're going to return List<Customer> customers = new List<Customer>(); // This is horrible foreach(WcfService.Customer wcfCustomer in wcfCustomers) { Customer customer = new Customer(); customer.Name = wcfCustomer.Name; customers.Add(customer); } return customers; } } I also plan on using a factory to decide which facade to use. // Factory pattern public class FacadeFactory() { public static ICustomerFacade CreateCustomerFacade() { // Determine the facade to use if (ConfigurationManager.AppSettings["DAL"] == "Sql") return new SqlCustomrFacade(); else return new WcfCustomrFacade(); } } This is how the DAL would typically be used. // Test application public class MyApp { public static void Main() { ICustomerFacade cf = FacadeFactory.CreateCustomerFacade(); cf.GetAll(); } } I appreciate your thoughts and time.

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  • Hibernate/Spring: getHibernateTemplate().save(...) Freezes/Hangs

    - by ashes999
    I'm using Hibernate and Spring with the DAO pattern (all Hibernate dependencies in a *DAO.java class). I have nine unit tests (JUnit) which create some business objects, save them, and perform operations on them; the objects are in a hash (so I'm reusing the same objects all the time). My JUnit setup method calls my DAO.deleteAllObjects() method which calls getSession().createSQLQuery("DELETE FROM <tablename>").executeUpdate() for my business object table (just one). One of my unit tests (#8/9) freezes. I presumed it was a database deadlock, because the Hibernate log file shows my delete statement last. However, debugging showed that it's simply HibernateTemplate.save(someObject) that's freezing. (Eclipse shows that it's freezing on HibernateTemplate.save(Object), line 694.) Also interesting to note is that running this test by itself (not in the suite of 9 tests) doesn't cause any problems. How on earth do I troubleshoot and fix this? Also, I'm using @Entity annotations, if that matters. Edit: I removed reuse of my business objects (use unique objects in every method) -- didn't make a difference (still freezes). Edit: This started trickling into other tests, too (can't run more than one test class without getting something freezing) Transaction configuration: <bean id="txManager" class="org.springframework.jdbc.datasource.DataSourceTransactionManager"> <property name="dataSource" ref="dataSource" /> </bean> <tx:advice id="txAdvice" transaction-manager="txManager"> <!-- the transactional semantics... --> <tx:attributes> <!-- all methods starting with 'get' are read-only --> <tx:method name="get*" read-only="true" /> <tx:method name="find*" read-only="true" /> <!-- other methods use the default transaction settings (see below) --> <tx:method name="*" /> </tx:attributes> </tx:advice> <!-- my bean which is exhibiting the hanging behavior --> <aop:config> <aop:pointcut id="beanNameHere" expression="execution(* com.blah.blah.IMyDAO.*(..))" /> <aop:advisor advice-ref="txAdvice" pointcut-ref="beanNameHere" /> </aop:config>

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  • Self referencing a table

    - by mue
    Hello, so I'm new to NHibernate and have a problem. Perhaps somebody can help me here. Given a User-class with many, many properties: public class User { public virtual Int64 Id { get; private set; } public virtual string Firstname { get; set; } public virtual string Lastname { get; set; } public virtual string Username { get; set; } public virtual string Email { get; set; } ... public virtual string Comment { get; set; } public virtual UserInfo LastModifiedBy { get; set; } } Here some DDL for the table: CREATE TABLE USERS ( "ID" BIGINT NOT NULL , "FIRSTNAME" VARCHAR(50) NOT NULL , "LASTNAME" VARCHAR(50) NOT NULL , "USERNAME" VARCHAR(128) NOT NULL , "EMAIL" VARCHAR(128) NOT NULL , ... "LASTMODIFIEDBY" BIGINT NOT NULL , ) IN "USERSPACE1" ; Database-table-field 'LASTMODIFIEDBY' holds for auditing purposes the Id from the User who is acting in case of inserts or updates. This would normally be an admin. Because the UI shall display not this Int64 but admins name (pattern like 'Lastname, Firstname') I need to retrieve these values by self referencing table USERS to itself. Next is, that a whole object of type User would be overkill by the amount of unwanted fields. So there is a class UserInfo with much smaller footprint. public class UserInfo { public Int64 Id { get; set; } public string Firstname { get; set; } public string Lastname { get; set; } public string FullnameReverse { get { return string.Format("{0}, {1}", Lastname ?? string.Empty, Firstname ?? string.Empty); } } } So here starts the problem. Actually I have no clue how to accomplish this task. Im not sure if I also must provide a mapping for class UserInfo and not only for class User. I'd like to integrate class UserInfo as Composite-element within the mapping for User-class. But I dont no how to define the mapping between USERS.ID and USERS.LASTMODIFIEDBY table-fields. Hopefully I decribes my problem clear enough to get some hints. Thanks alot!

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  • C++ Filling an 1D array to represent a n-dimensional object based on a straight line segment

    - by Ben
    I'm struggling to find a good way to put this question but here goes. I'm making a system that uses a 1D array implemented as double * parts_ = new double[some_variable];. I want to use this to hold co-ordinates for a particle system that can run in various dimensions. What I want to be able to do is write a generic fill algorithm for filling this in n-dimensions with a common increment in all direction to a variable size. Examples will serve best I think. Consider the case where the number of particles stored by the array is 4 In 1D this produces 4 elements in the array because each particle only has one co-ordinate. 1D: {0, 25, 50, 75}; In 2D this produces 8 elements in the array because each particle has two co-ordinates.. 2D: {0, 0, 0, 25, 25, 0, 25, 25} In 3D this produces 12 elements in the array because each particle now has three co-ordinates {0, 0, 0, 0, 0, 25, 0, 0, 50, ... } These examples are still not quite accurate, but they hopefully will suffice. The way I would do this normally for two dimensions: int i = 0; for(int x = 0; x < parts_size_ / dims_ / dims_ * 25; x += 25) { for(int y = 0; y < parts_size_ / dims_ / dims_ * 25; y += 25) { parts_[i] = x; parts_[i+1] = y; i+=2; // Indentation hates me today .< How can I implement this for n-dimensions where 25 can be any number? The straight line part is because it seems to me logical that a line is a somewhat regular shape in 1D, as is a square in 2D, and a cube in 3D. It seems to me that it would follow that there would be similar shapes in this family that could be implemented for 4D and higher dimensions via a similar fill pattern. This is the shape I wish to set my array to represent.

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