Search Results

Search found 46973 results on 1879 pages for 'return path'.

Page 648/1879 | < Previous Page | 644 645 646 647 648 649 650 651 652 653 654 655  | Next Page >

  • C++: Binding to a base class

    - by Helltone
    The following code works, but I'm not sure it is correct/portable. #include <iostream> #include <tr1/functional> class base { public: base(int v) : x(v) {} protected: int x; }; class derived : public base { public: bool test() { return (x == 42); } }; int main(int argc, char* argv[]) { base b(42); if(std::tr1::bind((bool (base::*)()) &derived::test, b)()) { std::cout << "ok\n"; } return 0; }

    Read the article

  • Java - Thread safety of ArrayList constructors

    - by andy boot
    I am looking at this piece of code. This constructor delegates to the native method "System.arraycopy" Is it Thread safe? And by that I mean can it ever throw a ConcurrentModificationException? public Collection<Object> getConnections(Collection<Object> someCollection) { return new ArrayList<Object>(someCollection); } Does it make any difference if the collection being copied is ThreadSafe eg a CopyOnWriteArrayList? public Collection<Object> getConnections(CopyOnWriteArrayList<Object> someCollection) { return new ArrayList<Object>(someCollection); }

    Read the article

  • WCF returning custom types

    - by Gena Verdel
    Hi. I'm a newbie to WCF, trying to perform relatively simple task. I'm trying to return list of objects read from the database but cannot overcome some really annoying exceptions. The question is very simple? What's wrong with the picture? [ServiceContract] public interface IDBService { [OperationContract] string Ping(string name); [OperationContract] InitBDResult InitBD(); } public InitBDResult InitBD() { _dc = new CentralDC(); InitBDResult result = new InitBDResult(); result.ord = _dc.Orders.First(); return result; } [DataContract] public class InitBDResult { //[DataMember] //public List<Order> Orders { get; set; } [DataMember] public Order ord { get; set; } }

    Read the article

  • Javascript: sort objects

    - by tom
    function Player() { var score; this.getScore = function() { return score; } this.setScore = function(sc) { score = sc; } } function compare(playerA, playerB) { return playerA.getScore() - playerB.getScore(); } var players = []; players['player1'] = new Player(); players['player2'] = new Player(); Array(players).sort(compare); I have code that is similar to the above. When I step through the code with a debugger, the compare function never gets called and the array isn't sorted. I'm not sure what's wrong with my code?

    Read the article

  • Technical non-terminating condition in a loop

    - by Snarfblam
    Most of us know that a loop should not have a non-terminating condition. For example, this C# loop has a non-terminating condition: any even value of i. This is an obvious logic error. void CountByTwosStartingAt(byte i) { // If i is even, it never exceeds 254 for(; i < 255; i += 2) { Console.WriteLine(i); } } Sometimes there are edge cases that are extremely unlikeley, but technically constitute non-exiting conditions (stack overflows and out-of-memory errors aside). Suppose you have a function that counts the number of sequential zeros in a stream: int CountZeros(Stream s) { int total = 0; while(s.ReadByte() == 0) total++; return total; } Now, suppose you feed it this thing: class InfiniteEmptyStream:Stream { // ... Other members ... public override int Read(byte[] buffer, int offset, int count) { Array.Clear(buffer, offset, count); // Output zeros return count; // Never returns -1 (end of stream) } } Or more realistically, maybe a stream that returns data from external hardware, which in certain cases might return lots of zeros (such as a game controller sitting on your desk). Either way we have an infinite loop. This particular non-terminating condition stands out, but sometimes they don't. A completely real-world example as in an app I'm writing. An endless stream of zeros will be deserialized into infinite "empty" objects (until the collection class or GC throws an exception because I've exceeded two billion items). But this would be a completely unexpected circumstance (considering my data source). How important is it to have absolutely no non-terminating conditions? How much does this affect "robustness?" Does it matter if they are only "theoretically" non-terminating (is it okay if an exception represents an implicit terminating condition)? Does it matter whether the app is commercial? If it is publicly distributed? Does it matter if the problematic code is in no way accessible through a public interface/API? Edit: One of the primary concerns I have is unforseen logic errors that can create the non-terminating condition. If, as a rule, you ensure there are no non-terminating conditions, you can identify or handle these logic errors more gracefully, but is it worth it? And when? This is a concern orthogonal to trust.

    Read the article

  • How do detect that transaction has already been started?

    - by xelurg
    I am using Zend_Db to insert some data inside a transaction. My function starts a transaction and then calls another method that also attempts to start a transaction and of course fails(I am using MySQL5). So, the question is - how do I detect that transaction has already been started? Here is a sample bit of code: try { Zend_Registry::get('database')->beginTransaction(); $totals = self::calculateTotals($Cart); $PaymentInstrument = new PaymentInstrument; $PaymentInstrument->create(); $PaymentInstrument->validate(); $PaymentInstrument->save(); Zend_Registry::get('database')->commit(); return true; } catch(Zend_Exception $e) { Bootstrap::$Log->err($e->getMessage()); Zend_Registry::get('database')->rollBack(); return false; } Inside PaymentInstrument::create there is another beginTransaction statement that produces the exception that says that transaction has already been started.

    Read the article

  • Clear sqlalchemy reflection cache

    - by OrganicPanda
    Hi all, I'm using sqlalchemy's reflection tools to get a Table object. I do this because these tables are dynamic and tables/columns can change. Here's the code I'm using: def getTableByReflection(self, tableName, metadata, engine): return Table(tableName, metadata, autoload = True, autoload_with = engine) The problem is that when the above code is run twice it seems to return the same results regardless of whether or not the columns have changed. I have tried refreshing using the mysession.refresh(mytable) but that fails because the table is not attached to any metadata - which makes sense but then why am I seeing cached results? Is there any way to tell the metadata/engine/session to forget about this table and let me load it cleanly?

    Read the article

  • Asking browsers to cache as aggressively as possible

    - by balpha
    This is about a web app that serves images. Since the same request will always return the same image, I want the accessing browsers to cache the images as aggressively as possible. I pretty much want to tell the browser Here's your image. Go ahead and keep it; it's really not going to change for the next couple of days. No need to come back. Really. I promise. I do, so far, set Cache-Control: public, max-age=86400 Last-Modified: (some time ago) Expires: (two days from now) and of course return a 304 not modified if the request has the appropriate If-Modified-Since header. Is there anything else I can do (or anything I should do differently) to get my message across to the browsers? The app is hosted on the Google App Engine, in case that matters.

    Read the article

  • Strange lifecycle behaviour with f:ajax and valueChangedListener

    - by gerry
    I want to use the f:ajax tag to update a part of a page with a editor gui, which style depends on a selectOneMenu and its selected item. The problem is, that if the ajax is called the server first renders the editor and then executes the valueChangedListener method. In my JSF2.0 / Facelets app I've the following code: ... <h:selectOneMenu id="typeSelect" validator="#{addEntityBean.checkType}" value="#{addEntityBean.selectedTypeAsString}" valueChangeListener="#{addEntityBean.selectedTypeChanged}"> <f:ajax render="editorGrid"/> <f:selectItems value="#{addEntityBean.entityTypeListAsString}"/> </h:selectOneMenu> ... <h:panelGrid id="editorGrid" columns="2" binding="#{addEntityBean.dynamicEditorGrid}" /> The BackingBean code looks like this: public String getSelectedTypeAsString() { return selectedTypeAsString; } public void setSelectedTypeAsString(String selectedType) { this.selectedTypeAsString = selectedType; } public Class<? extends Entity> getSelectedType() { log.severe("getSelectedType"); Class<? extends Entity> res = null; if(selectedTypeAsString != null){ int index = entityTypeListAsString.indexOf(selectedTypeAsString); res = entityTypeList.get(index); } return res; } public void selectedTypeChanged(ValueChangeEvent event){ setSelectedTypeAsString((String)event.getNewValue()); Class<? extends Entity> clazz = getSelectedType(); if(clazz != null){ try { setEntity(clazz.newInstance()); } catch (Exception e) { log.severe(e); } } else{ setEntity(null); } } public HtmlPanelGrid getDynamicEditorGrid() { HtmlPanelGrid grid = DynamicHtmlComponentCreator.createHtmlPanelGrid(); Entity entity = getEntity(); if(entity != null){ log.severe("getEntity() -->"+entity.getClassName()); grid = (HtmlPanelGrid)buildGui(grid, entity, "entityBean.entity", false); } else log.severe("getEntity() --> null"); return grid; } The problem is, that the server logs show that at first the getDynamicEditorGrid() is executed. And later the selectedTypeChanged()-listener-method. So everytime the selected editor style type is update one selection later. I.e. after a page reload (the type is initally null) the user selects the A, now the getDynamicEditorGrid() is executed again with type null and after that the type is changed to A. Again the user selects now B (after A) and now the getDynamicEditorGrid() is executed with the type A and after that the type is changed to B. What is wrong with my code? How can I fix this really strange behavior...

    Read the article

  • Returnimng collection of interfaces

    - by apoorv020
    I have created the following interface public interface ISolutionSpace { public boolean isFeasible(); public boolean isSolution(); public Set<ISolutionSpace> generateChildren(); } However, in the implementation of ISolutionSpace in a class called EightQueenSolutionSpace, I am going to return a set of EightQueenSolutionSpace instances, like the following stub: @Override public Set<ISolutionSpace> generateChildren() { return new HashSet<EightQueenSolutionSpace>(); } However this stub wont compile. What changes do I need to make? EDIT: I tried 'HashSet' as well and had tried using the extends keyword. However since 'ISolutionSpace' is an interface and EightQueenSolutionSpace is an implementation(and not a subclass) of 'ISolutionSpace', it is still not working.

    Read the article

  • Hibernate, select by id or unique column

    - by Nican
    I am using hibernate for Java, and I want to be able to select users by id or by name from the database. Nice thing about Hibernate is that it caches the result by id, but I seem to be unable to make it cache by name. static Session openSession = Factory.openSession(); public static User GetUser(int Id) { return (User) openSession.get(User.class, new Integer(Id)); } public static User GetUser( String Name ){ return (User) openSession.createCriteria( User.class ). add( Restrictions.eq("username", Name) ). uniqueResult(); } If I use GetUser(1) many times, hibernate will only show that it executed the first time. But every time I use GetUser("user1"), hibernate shows that it is executing a new query to database. What would be the best way to have the string identifier be cached also?

    Read the article

  • GoogleMaps API v3 - Need help with two "click" event scenarios. Need similar functionality to v2 AP

    - by Nathan Raley
    In version 2 of the API the map click event returned an Overlay, LatLng, Overlaylatlng. I used this to create a generic map event that would either retrieve the coordinates of the Map click event, or return the coordinates of a Marker or other type of Overlay. Now that API v3 doesn't return the Overlay or Overlaylatlng during the map click event, how can I go about creating a generic "click" event for the map that works if the user clicks on a marker or overlay? I really don't want to create a click event for each marker I have on my page as I am creating anywhere from a handful to a couple thousand markers. Also, I had to create a custom ImageMapType in order to display the StreetViewOverlay like we could do in v2 of the API because I couldn't find anywhere that told me how to add the StreetViewOverlay without the pegman icon. How can I go about retrieving the LatLng coordinates of a click on this overlay type as well?

    Read the article

  • What's the RegEx to make sure that delimiters are escaped?

    - by Kuyenda
    I'm looking for a regular expression that will check whether or not delimiters in a string are escaped with a backward slash. The delimiters I am concerned about are comma (\,), colon (\:), semicolon (\;) and of course the backward slash itself has to be escaped (\). For example, the string "test" should return a match because there are no delimiters in it, and no escaping is necessary. The string "te\;st" would return a match because the semicolon delimiter is escaped. "te;st" and "t\;s:t" would both fail because the both contain at least one delimiter that is not escaped. I know that I need a conditional and a positive look behind, and this is what I have so far, but it is not giving me the expected answer. ^(?<delimiter>[:;,\\])?(?(delimiter)\(?<=(?:\\\\)*\\)k<delimiter>|.)$ Any suggestions on how I can make this work? Thanks.

    Read the article

  • Using system time directly to get random numbers

    - by Richard Mar.
    I had to return a random element from an array so I came up with this placeholder: return codes[(int) (System.currentTimeMillis() % codes.length - 1)]; Now than I think of it, I'm tempted to use it in real code. The Random() seeder uses system time as seed in most languages anyway, so why not use that time directly? As a bonus, I'm free from the worry of non-random lower bits of many RNGs. It this hack coming back to bite me? (The language is Java if that's relevant.)

    Read the article

  • Objective C: App freezes when using a timer

    - by Chris
    It took me hours to figure out how to implement a timer into my program, but when it runs, the app doesn't load completely as it did before the timer. In my main.m: int main (int argc, const char * argv[]) { NSAutoreleasePool * pool = [[NSAutoreleasePool alloc] init]; OutLauncher *theLauncher = [[OutLauncher alloc] init]; NSTimer *theTimer = [theLauncher getTimer]; [theTimer retain]; [[NSRunLoop currentRunLoop] addTimer: theTimer forMode: NSDefaultRunLoopMode]; [[NSRunLoop currentRunLoop] run]; [pool release]; return 0; } The file OutLauncher is being imported into that, which looks like this: - (void)doStuff { NSLog( @"Doing Stuff"); } - (NSTimer *)getTimer{ NSTimer *theTimer; theTimer = [NSTimer scheduledTimerWithTimeInterval:1.0 target:self selector: @selector(doStuff) userInfo:nil repeats:YES]; return [theTimer autorelease]; } The timer works, the console updates every second with the phrase "doing stuff" but the rest of the program just won't load. It will if I comment out the code I added to int main though

    Read the article

  • Why have private fields in data contracts modified through public ones?

    - by Nordvind
    When you make a new WCF project, sample service is generated for you. The default data contract is (I've just changed the string type field title): [DataContract] public class CompositeType { bool boolValue = true; string name = ""; [DataMember] public bool BoolValue { get { return boolValue; } set { boolValue = value; } } [DataMember] public string Name { get { return name; } set { name = value; } } } What is the point of having those private fields boolValue and name? Is it a good practice writing some data sanitizing or some other manipulations in contract, thus bloating it? It seems the only sane reason for me not writing to fields directly. So is it a bloatware or it has some reason behind it?

    Read the article

  • Regular Expression to get the size value of a CSS property?

    - by thiesdiggity
    I wrote a regular expression to get the size from a CSS property: /(([+-]?\d*\.?\d+(\s)*(px|em|ex|pt|in|pc|mm|cm)?)|thin|medium|thick)(\s|;|$)/i but for some reason its not working as intended. For example, when I run the following: preg_match_all('/(([+-]?\d*\.?\d+(\s)*(px|em|ex|pt|in|pc|mm|cm)?)|thin|medium|thick)(\s|;|$)/i', "border-bottom:1px solid #99999;", $matches); It outputs: 1px 99999; But I only want the 1px value returned. I understand why its returning the above but can't seem to figure out how to only return the size and not the color value. I tried using the following negative lookbehind but it's not working either: /(((?<!#\d{3}|#\d{6})[+-]?\d*\.?\d+(\s)*(px|em|ex|pt|in|pc|mm|cm)?)|thin|medium|thick)(\s|;|$)/i I want to use preg_match_all for those CSS properties that can have multiple size values (i.e. margin). Anyone have any ideas how to get this regex to return only the size values? Thanks for your help!

    Read the article

  • Reading the .vcproj file with C#

    - by Dulantha Fernando
    We create the vcproj file with the makefileproj keyword so we can use our own build in VS. My question is, using C#, how do you read the "C++" from the following vcproj file: <?xml version="1.0" encoding="Windows-1252"?> <VisualStudioProject ProjectType="Visual C++" Version="8.00" Name="TestCSProj" ProjectGUID="{840501C9-6AFE-8CD6-1146-84208624C0B0}" RootNamespace="TestCSProj" Keyword="MakeFileProj" > <Platforms> <Platform Name="x64" /> <Platform Name="C++" ===> I need to read "C++" /> </Platforms> I used XmlNode and got upto the second Platform: String path = "C:\\blah\\TestCSProj\\TestCSProj\\TestCSProj.vcproj"; FileStream fs = new FileStream(path, FileMode.Open, FileAccess.Read, FileShare.ReadWrite); XmlDocument xmldoc = new XmlDocument(); xmldoc.Load(fs); XmlNodeList oldFiles = xmldoc.GetElementsByTagName("Platform"); XmlAttribute name = oldFiles[1].Attributes[0]; Console.WriteLine(name.Name); This will print Name, but I need "C++". How do I read that? Thank you very much in advance

    Read the article

  • How to create a reference tables for collection classes using fluent nhibernate

    - by Akk
    How can i create a 3 table schema from the following model classes. public class Product { public int Id {get; set;} public string Name {get; set;} public IList<Photo> Photos {get; set;} } public class Photo { public int Id {get; set;} public string Path {get; set;} } I want to create the following table structure in the database: Product ------- Id Name ProductPhotos ------------- ProductId (FK Products.Id) PhotoId (FK Photos.Id) Photos ------ Id Path How i can express the above Database Schema using Fluent NHibernate? I could only manage the following the Mapping but this does not get me the 3rd Photo ref table. public class ProductMap : ClassMap<Product> { public CityMap() { Id(x => x.Id); Map(x => x.Name); Table("Products"); HasMany(x => x.Photos).Table("ProductPhotos").KeyColumn("ProductId"); } }

    Read the article

  • Predicates and Lists

    - by George
    Hello guys, I have a generic list. Some elements of this list belong to a parent element. I retrieved all these elements from a database and i want to recursively build a tree with them. So, here's what i'm thinking: Here is my predicate: public static bool FindChildren(Int32 parentId,CategoryMapping catMapping) { if (catMapping.parentId == parentId) { return true; } else { return false; } } root = list[0]; root.childrenElements = root.FindAll(FindChildren(root.id,???) I can't figure out how this would work. How can i do this kind of predicate?

    Read the article

  • C++ cin returns 0 for integer no matter what the user inputs

    - by kevin dappah
    No matter the cin it continues to to output 0 for score. Why is that? I tried returning the "return 0;" but still no go :/ #include "stdafx.h" #include <iostream> using namespace std; // Variables int enemiesKilled; const int KILLS = 150; int score = enemiesKilled * KILLS; int main() { cout << "How many enemies did you kill?" << endl; cin >> enemiesKilled; cout << "Your score: " << score << endl; return 0; }

    Read the article

  • Can the lock function be used to implement thread-safe enumeration?

    - by Daniel
    I'm working on a thread-safe collection that uses Dictionary as a backing store. In C# you can do the following: private IEnumerable<KeyValuePair<K, V>> Enumerate() { if (_synchronize) { lock (_locker) { foreach (var entry in _dict) yield return entry; } } else { foreach (var entry in _dict) yield return entry; } } The only way I've found to do this in F# is using Monitor, e.g.: let enumerate() = if synchronize then seq { System.Threading.Monitor.Enter(locker) try for entry in dict -> entry finally System.Threading.Monitor.Exit(locker) } else seq { for entry in dict -> entry } Can this be done using the lock function? Or, is there a better way to do this in general? I don't think returning a copy of the collection for iteration will work because I need absolute synchronization.

    Read the article

  • Can the Visual Studio (2010) Command Window handle "external tools" with project/solution relative p

    - by ee
    I have been playing with the Command Window in Visual Studio (View-Other Windows-Command Window). It is great for several mouse-free scenarios. (The autocompleting file "Open" command rocks in a non-trivial solution.) That success got me thinking and experimenting: Possibility 1.1: You can use the Alias commands to create custom commands Possibility 1.2: You can use the Shell command to run arbitrary executables and specify parameters (and pipe the result to the output or command windows) Possibility 2: A previously setup external tool definition (with project-relative path variables) could be run from the command window What I am stuck on is: There doesn't appear to be a way to send parameters to an aliased command (and thus the underlying Shell call) There doesn't appear to be a way to use project/solution relative paths ($SolutionDir/$ProjectDir) on a Shell call Using absolute paths in Shell works, but is fragile and high-maintenance (one alias for each needed use case). Typically you want the command to run against a file relative to your project/solution. It seems you can't run the traditional external tools (Tools-External Tools...) in the command window Ultimately I want the external tool functionality in the command window in some way. Can anyone see a way to do this? Or am I barking up the wrong tree? So my questions: Can an "external tool" of some sort (using relative project/solution path parameters) be used in the Command Window? If yes, How? If no, what might be a suitable alternative?

    Read the article

  • scripting subtlties [closed]

    - by jpmyob
    Possible Duplicates: When to use anonymous JavaScript functions? Is there any difference between var name = function() {} & function name() {} in Javascript? in javascript (and other scripting languages) what is the 'real' difference between these two syntax: a) function myFun(x) { yadda yadda } b) myFun(x) = function { yadda yadda } to a casual observer - no 'real' difference - you still call either as myFun()...and they still return the same thing, so if reference and return are identical - is it a preference or is there some difference in the code parsing engine that treats these two differently - and if so - when would you use one over the other???

    Read the article

  • CDN for Images in ASP.NET

    - by Chris
    I am in the process of moving all of the images in my web application over to a CDN but I want to easily be able to switch the CDN on or off without having to hard code the path to the images. My first thought was to add an HttpHandler for image extensions that depending whether a variable in the web.config (something like ) will serve the image from the server or from the CDN. But after giving this a little though I think I've essentially ruled this out as it will cause ASP.NET to handle the request for every single image, thus adding overhead, and it might actually completely mitigate the benefits of using a CDN. An alternative approach is, since all of my pages inherit from a base page class, I could create a function in the base class that determines what path to serve the files from based off the web.config variable. I would then do something like this in the markup: <img src='<%= GetImagePath()/image.png' /> I think this is probably what I'll have to end up doing, but it seems a little clunky to me. I also envision problems with the old .NET error of not being able to modify the control collection because of the "<%=" though the "<%#" solution will probably work. Any thoughts or ideas on how to implement this?

    Read the article

< Previous Page | 644 645 646 647 648 649 650 651 652 653 654 655  | Next Page >