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  • JTable Boolean cell .. how to read it

    - by dimitar
    Hello guys, i have a table with a column that contains Boolean type. now when i try to run a program i have a problem: System.out.println(table.getColumnClass(5)); b= (Boolean)table.getValueAt(row, 5); It prints class java.lang.Boolean but also: Exception in thread "AWT-EventQueue-0" java.lang.ClassCastException: java.lang.String cannot be cast to java.lang.Boolean and i even try with b= (Boolean)table.getValueAt(row, 5); b= Boolean.parseBoolean((String)table.getValueAt(row, 5)); b= table.getValueAt(row, 5); but those show error too. So how to fix this guys?

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  • verilog or systemc for testbench

    - by Alphaneo
    I am assigned with the task of verifying some verilog based RTL code. Now, coding the RTL testbench using verilog seems to be very difficult (for me). So I would like to try one of the following. - Try providing a PLI interface to the RTL and thereby invoke 'C functions for testing - Using system 'C for interfacing the 'C functions PS: I already have a extensive 'C code that was used for testing the behavioral model. I am new to the world of hardware programming. Any pointers would be greatly appreciated.

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  • facebook graph api don´t publish to news feed

    - by rizidoro
    hi, im trying to update my news feed on facebook. Im using the new graph api. I can connect to graph, but when i try to publish some content to the feed object, nothing happens. here´s my code: <?php $token = "xxxx"; $fields = "message=test&access_token=$token"; $c = curl_init("http://graph.facebook.com/me/feed"); curl_setopt($c,"CURLOPT_POST", true); curl_setopt($c,"CURLOPT_POSTFIELDS",$fields); $r = curl_exec($c); print_r($r); this returns: {"error":{"type":"QueryParseException","message":"An active access token must be used to query information about the current user."}}1 then I try to pass access_token via GET: $c = curl_init("http://graph.facebook.com/me/feed?access_token=$token"); this returns: {"data":[]}1 Am I doing something wrong? thanks

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  • IE Automation - How to Trap 'NewProcess' event

    - by dpb
    In Environment - Standard User, Win7x64, IE8 on opening Unprotected URL, IE 8 will first start a tab with low integrity and the swap out this tab with another tab of medium integrity. This is done behind the scene and the original IWebBrowser2 pointer is lost. I want to catch the 'NewProcess' Event which will get generated during this swap out, please help me how to go about this. Sample code can help me, me using C++ Ref - http://blogs.msdn.com/b/ieinternals/archive/2011/08/03/internet-explorer-automation-protected-mode-lcie-default-integrity-level-medium.aspx Thank You

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  • Resizing page format on iReport

    - by pringlesinn
    I've been trying to print a pdf made from iReport in less than a page A4. it's like half A4 page height. I'm using a Line Matrix printer, doesn't matter which one. So, when I try to print 2 files at same file, it should print everything on the right place, but just first file is printed correctly. The second one is based on a A4 page format, and just starts printing after A4 page height is over, skipping a big blank. Where can I set the size of page in iReport? The only thing I could do was setting size of what is shown on screen while I edit the file. I tried my best to explain the situation, any doubts, ask me and I'll try even harder.

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  • Why do Pascal control structures appear to be inconsistent?

    - by 70Mike
    Most Pascal control structures make sense to me, like: for ... do {statement}; if (condition) then {statement}; while (condition) do {statement}; where the {statement} is either a single statement, or a begin ... end block. I have a problem with: repeat {statement-list} until (expression); try {statement-list} except {statement-list} end; Wouldn't it be better that repeat and try have the same general structure, accepting only a single statement or a begin ... end block, instead of having a statement-list that's not formally blocked with a begin and an end?

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  • Errors caught by WBT, but not BBT and vice versa

    - by David Relihan
    Hi Folks, Can you think of one type of error that might be found using White-Box testing, and one type using Black-Box testing. i.e. an error that would be found by one and not the other. For WBT there would null else statements, but what would you catch with BBT and not WBT??? BTW this question is just based on my own personal study - I'm not getting free marks out of this!!!! Thanks,

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  • How to get the current exception without having passing the variable?

    - by Pierre-Alain Vigeant
    I am looking for a way to retrieve the current exception without having to pass it as a variable. Suppose the following code public void MakeItFail() { try { throw new FailException(); } catch // Yes I'm aware that this shouldn't be done, but I don't want to go through all the code base and change it { ShowMessage("An error occured"); } } public void ShowMessage(string message) { // How can I retrieve the exception here } In the watch window, I can use $exception to get the current exception. Is there is a code equivalent?

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  • Exceptions thrown in jQuery AJAX callbacks swallowed?

    - by MikeWyatt
    Is there any way to handle exceptions thrown from AJAX callbacks in jQuery, other than adding a try..catch block to each callback? The error function is not called in this situation. $.ajax( { url: 'myurl.rails', success: function( data ) { throw 'Oh no!'; }, error: function ( xhr, textStatus, errorThrown ) { console.log( 'AJAX call failed', xhr, textStatus, errorThrown ); } } );

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  • Error Handling for Application in PHP

    - by Zubair1
    I was wondering if someone can show me a good way to handle errors in my PHP app, that i am also easily able to reuse in my codes. So far i have been using the following functions: Inline Errors function display_errors_for($fieldname) { global $errors; if (isset($errors[$fieldname])) { return '<label for="' .$fieldname. '" class="error">' . ucfirst($errors[$fieldname]). '</label>'; } else { return false; } } All Errrors function display_all_errors($showCounter = true) { global $errors; $counter = 0; foreach ($errors as $errorFieldName => $errorText) { if ($showCounter == true) { $counter++; echo '<li>' . $counter . ' - <label for="' .$errorFieldName. '">' .$errorText. '</label></li>'; } else { echo '<li><label for="' .$errorFieldName. '">' .$errorText. '</label></li>'; } } } I have a $errors = array(); defined on the top of my global file, so it is appended to all files. The way i use it is that if i encounter an error, i push a new error key/value to the $errors array holder, something like the following: if (strlen($username) < 3) { $errors['username'] = "usernames cannot be less then 3 characters."; } This all works great and all, But i wondering if some one has a better approach for this? with classes? i don't think i want to use Exceptions with try/catch seems like an overkill to me. I'm planning to make a new app, and i'll be getting my hands wet with OOP alot, though i have already made apps using OOP but this time i'm planning to go even deeper and use OOP approach more extensively. What i have in mind is something like this, though its just a basic class i will add further detail to it as i go deeper and deeper in my app to see what it needs. class Errors { public $errors = array(); public function __construct() { // Initialize Default Values // Initialize Methods } public function __destruct() { //nothing here too... } public function add($errorField, $errorDesc) { if (!is_string($errorField)) return false; if (!is_string($errorDesc)) return false; $this->errors[$errorField] = $errorDesc; } public function display($errorsArray) { // code to iterate through the array and display all errors. } } Please share your thoughts, if this is a good way to make a reusable class to store and display errors for an entire app, or is getting more familiar with exceptions and try/catch my only choice?

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  • How do I create a Spring 3 + Tiles 2 webapp using REST-ful URLs?

    - by Ichiro Furusato
    I'm having a heck of a time resolving URLs with Spring 3.0 MVC. I'm just building a HelloWorld to try out how to build a RESTful webapp in Spring, nothing theoretically complicated. All of the examples I've been able to find are based on configurations that pay attention to file extensions ("*.htm" or "*.do"), include an artificial directory name prefix ("/foo") or even prefix paths with a dot (ugly), all approaches that use some artificial regex pattern as a signal to the resolver. For a REST approach I want to avoid all that muck and use only the natural URL patterns of my application. I would assume (perhaps incorrectly) that in web.xml I'd set a url-pattern of "/*" and pass everything to the DispatcherServlet for resolution, then just rely on URL patterns in my controller. I can't reliably get my resolver(s) to catch the URL patterns, and in all my trials this results in a resource not found error, a stack overflow (loop), or some kind of opaque Spring 3 ServletException stack trace — one of my ongoing frustrations with Spring generally is that the error messages are not often very helpful. I want to work with a Tiles 2 resolver. I've located my *.jsp files in WEB-INF/views/ and have a single line index.jsp file at the application root redirecting to the index file set by my layout.xml (the Tiles 2 Configurer). I do all the normal Spring 3 high-level configuration: <mvc:annotation-driven /> <mvc:view-controller path="/" view-name="index"/> <context:component-scan base-package="com.acme.web.controller" /> ...followed by all sorts of combinations and configurations of UrlBasedViewResolver, InternalResourceViewResolver, UrlFilenameViewController, etc. with all manner of variantions in my Tiles 2 configuration file. Then in my controller I've trying to pick up my URL patterns. Problem is, I can't reliably even get the resolver(s) to catch the patterns to send to my controller. This has now stretched to multiple days with no real progress on something I thought would be very simple to implement. I'm perhaps trying to do too much at once, though I would think this should be a simple (almost a default) configuration. I'm just trying to create a simple HelloWorld-type application, I wouldn't expect this is rocket science. Rather than me post my own configurations (which have ranged all over the map), does anyone know of an online example that: shows a simple Spring 3 MVC + Tiles 2 web application that uses REST-ful URLs (i.e., avoiding forced URL patterns such as file extensions, added directory names or dots) and relies solely on Spring 3 code/annotations (i.e., nothing outside of Spring MVC itself) to accomplish this? Is there an easy way to do this? Thanks very much for any help.

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  • JAXB Web Services: Multiple Object Marshalling

    - by Luke Evans
    I can marshal and unmarshal 1 object with no problems (in netbeans); I need to know how to do this with multiple objects? I can't generate anything but null pointer exceptions when trying to unmarshal 3 objects into an array from XML; so I don't even know if I've marshalled the 3 out correctly. I know the basic idea of declaring the object, then using the jaxbu or jaxbm command, but I'd like to see this working for more than one object. **TLDR: How do I marshal/unmarshal multiple objects of a single class into/out of XML?? THANKS Code I have that marshals one object from XML: try { JAXBContext jc = JAXBContext.newInstance ("myOffers"); Unmarshaller u = jc.createUnmarshaller (); myOffers.Offer flight = (myOffers.Offer) u.unmarshal( new FileInputStream( "offers.xml" )); System.out.println ("Airline is : " + flight.getAirline()); System.out.println ("Origin is : " + flight.getOrigin()); System.out.println ("Destination is : " + flight.getDestination()); System.out.println ("Seats available : " + flight.getSeats()); System.out.println("Proximity to City Centre is : " + flight.getProximity()); System.out.println("Currency : " + flight.fare.getCurrency()); System.out.println("Value : " + flight.fare.getValue()); } catch (JAXBException e) { System.out.println("Error " + e);} ok so the Xml is: <?xml version="1.0" encoding="UTF-8" standalone="yes"?> <ns2:offer xmlns:ns2="http://simple.example.com/CInfoXmlDoc"> <Origin>Nottingham</Origin> <Destination>Istanbul</Destination> <Airline>Lufthansa</Airline> <Proximity>10</Proximity> <Seats>260</Seats> <Fare> <Currency>GBP</Currency> <Value>300</Value> </Fare> </ns2:offer> <?xml version="1.0" encoding="UTF-8" standalone="yes"?> <ns2:offer xmlns:ns2="http://simple.example.com/CInfoXmlDoc"> <Origin>Birmingham</Origin> <Destination>Cairo</Destination> <Airline>Monarch</Airline> <Proximity>15</Proximity> <Seats>350</Seats> <Fare> <Currency>GBP</Currency> <Value>300</Value> </Fare> </ns2:offer> public static void main(String[] args) throws FileNotFoundException { int i = 0; int arraySize = 2; myOffers.Offer offer[] = new myOffers.Offer[arraySize]; offer[i] = new myOffers.Offer(); offer[i].fare = new myOffers.Offer.Fare(); offer[i].setAirline("Lufthansa"); offer[i].setOrigin("Nottingham"); offer[i].setDestination("Istanbul"); offer[i].setSeats(260); offer[i].setProximity(10); offer[i].fare.currency = "GBP"; offer[i].fare.value = 300; i++; offer[i] = new myOffers.Offer(); offer[i].fare = new myOffers.Offer.Fare(); offer[i].setAirline("Monarch"); offer[i].setOrigin("Birmingham"); offer[i].setDestination("Cairo"); offer[i].setSeats(350); offer[i].setProximity(15); offer[i].fare.currency = "GBP"; offer[i].fare.value = 300; try { int n = 0; FileOutputStream f = new FileOutputStream("offers.xml"); javax.xml.bind.JAXBContext jaxbCtx = javax.xml.bind.JAXBContext.newInstance(offer[n].getClass().getPackage().getName()); javax.xml.bind.Marshaller marshaller = jaxbCtx.createMarshaller(); marshaller.setProperty(javax.xml.bind.Marshaller.JAXB_ENCODING, "UTF-8"); //NOI18N marshaller.setProperty(javax.xml.bind.Marshaller.JAXB_FORMATTED_OUTPUT, Boolean.TRUE); while (n < arraySize) { marshaller.marshal(offer[n], f); n++; } } catch (javax.xml.bind.JAXBException ex) { // XXXTODO Handle exception java.util.logging.Logger.getLogger("global").log(java.util.logging.Level.SEVERE, null, ex); //NOI18N } } Which was generated by my marshal code found here: public static void main(String[] args) throws FileNotFoundException { int i = 0; int arraySize = 2; myOffers.Offer offer[] = new myOffers.Offer[arraySize]; offer[i] = new myOffers.Offer(); offer[i].fare = new myOffers.Offer.Fare(); offer[i].setAirline("Lufthansa"); offer[i].setOrigin("Nottingham"); offer[i].setDestination("Istanbul"); offer[i].setSeats(260); offer[i].setProximity(10); offer[i].fare.currency = "GBP"; offer[i].fare.value = 300; i++; offer[i] = new myOffers.Offer(); offer[i].fare = new myOffers.Offer.Fare(); offer[i].setAirline("Monarch"); offer[i].setOrigin("Birmingham"); offer[i].setDestination("Cairo"); offer[i].setSeats(350); offer[i].setProximity(15); offer[i].fare.currency = "GBP"; offer[i].fare.value = 300; try { int n = 0; FileOutputStream f = new FileOutputStream("offers.xml"); javax.xml.bind.JAXBContext jaxbCtx = javax.xml.bind.JAXBContext.newInstance(offer[n].getClass().getPackage().getName()); javax.xml.bind.Marshaller marshaller = jaxbCtx.createMarshaller(); marshaller.setProperty(javax.xml.bind.Marshaller.JAXB_ENCODING, "UTF-8"); //NOI18N marshaller.setProperty(javax.xml.bind.Marshaller.JAXB_FORMATTED_OUTPUT, Boolean.TRUE); while (n < arraySize) { marshaller.marshal(offer[n], f); n++; } } catch (javax.xml.bind.JAXBException ex) { // XXXTODO Handle exception java.util.logging.Logger.getLogger("global").log(java.util.logging.Level.SEVERE, null, ex); //NOI18N } } Apologies, I'm fining this editor quite appalling but thats another matter. Whats wrong with [code][/code] tags...

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  • Shipping GNU/Linux Firefox plugin with shared libraries (for installation with no root access)

    - by Vi
    The application is a Firefox plugin (loaded from $HOME/.mozilla/plugins), so wrapper script that sets LD_LIBRARY_PATH is not an easy option. RPATH, as far as I know, cannot refer to $HOME and can be only absolue path. Firefox tries to dlopen it's plugin from ~/.mozilla/plugins but fails (because it depends on shared libraries installed somewhere in the user home directory). Modifying Firefox menu item to provide a wrapper (with LD_LIBRARY_PATH) around Firefox is too hacky. What should installer script do (without root access) to make standard firefox load plug-ins that depends on out shared library? Should I just try to make embed everything into that .so to remove dependencies? Should I try to make installer script to finish linking or patch RPATH during the installation phase?

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  • how to filter data from xml file for displaying only selected as nodes in treeview

    - by michale
    I have an xml file named "books.xml" provided in the link "http://msdn.microsoft.com/en-us/library/windows/desktop/ms762271(v=vs.85).aspx". What my requirement was to disaplay only the <title> from xml information as nodes in tree view. But when i did the following coding its displaying all the values as nodes like "catalog" as rootnode, book as parent node for all then author,title,genre etc as nodes but i want only root node catalogue and title as nodes not even book. Can any body guide me what modification i need to do in the exisitng logic for displaying title as nodes OpenFileDialog dlg = new OpenFileDialog(); dlg.Title = "Open XML document"; dlg.Filter = "XML Files (*.xml)|*.xml"; dlg.FileName = Application.StartupPath + "\\..\\..\\Sample.xml"; if (dlg.ShowDialog() == DialogResult.OK) { try { //Just a good practice -- change the cursor to a //wait cursor while the nodes populate this.Cursor = Cursors.WaitCursor; //First, we'll load the Xml document XmlDocument xDoc = new XmlDocument(); xDoc.Load(dlg.FileName); //Now, clear out the treeview, //and add the first (root) node treeView1.Nodes.Clear(); treeView1.Nodes.Add(new TreeNode(xDoc.DocumentElement.Name)); TreeNode tNode = new TreeNode(); tNode = (TreeNode)treeView1.Nodes[0]; //We make a call to addTreeNode, //where we'll add all of our nodes addTreeNode(xDoc.DocumentElement, tNode); //Expand the treeview to show all nodes treeView1.ExpandAll(); } catch (XmlException xExc) //Exception is thrown is there is an error in the Xml { MessageBox.Show(xExc.Message); } catch (Exception ex) //General exception { MessageBox.Show(ex.Message); } finally { this.Cursor = Cursors.Default; //Change the cursor back } }} //This function is called recursively until all nodes are loaded private void addTreeNode(XmlNode xmlNode, TreeNode treeNode) { XmlNode xNode; TreeNode tNode; XmlNodeList xNodeList; if (xmlNode.HasChildNodes) //The current node has children { xNodeList = xmlNode.ChildNodes; for (int x = 0; x <= xNodeList.Count - 1; x++) //Loop through the child nodes { xNode = xmlNode.ChildNodes[x]; treeNode.Nodes.Add(new TreeNode(xNode.Name)); tNode = treeNode.Nodes[x]; addTreeNode(xNode, tNode); } } else //No children, so add the outer xml (trimming off whitespace) treeNode.Text = xmlNode.OuterXml.Trim(); }

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  • Why is this HTTP request continually looping?

    - by alex
    I'm probably overlooking something really obvious here. Comments are in to help explain any library specific code. public function areCookiesEnabled() { $random = 'cx67ds'; // set cookie cookie::set('test_cookie', $random); // try and get cookie, if not set to false $testCookie = cookie::get('test_cookie', false); $cookiesAppend = '?cookies=false'; // were we able to get the cookie equal ? $cookiesEnabled = ($testCookie === $random); // if $_GET['cookies'] === false , etc try and remove $_GET portion if ($this->input->get('cookies', false) === 'false' AND $cookiesEnabled) { url::redirect(str_replace($cookiesAppend, '', url::current())); // redirect return false; } // all else fails, add a $_GET[] if ( ! $cookiesEnabled) { url::redirect(url::current().$cookiesAppend); } return $cookiesEnabled; }

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  • Google Custom Search Engine not giving the expected search result.

    - by iecut
    Hi, I have been trying to create a new google custom search engine, but when I try some query,the search engine it is not giving me the expected search result.On some queries it is working fine, but on other queries, it says"no result". I tried adding the URL of the website that I wanted to search for, but there are certain pages and keywords that are not coming up in the search result when I try to search for the keyword of that page. I tired adding both the main page URL and the URL of the sub page that I want to search for, but nothing is working. There are some sub pages to the main URL that are coming in the search result.

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  • HOw I can verify my SQL / SQL Pl syntax

    - by rima
    Hi all Sorry my English is bad.I hope u can get what I want. I have lots of *.sql files that i want to write a program to compile them and if there is any issue(problem or mistake) report me. One of my friend write an IDE for java,as I remember he use javac to generate the codes error,in other hand maybe u see when u try to write code in a Visual stadio or Netbean the IDE generate errors for u.so now I want to know any one have any idea how I can do it for my sql files? In other mean I want to write a Editor for SQL files(PL/SQL) that compile my code and tell me what is my error. this problem raise up when I try to compile all of them in SQL PLUS,it's so boring. please help me...

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  • Hibernate SessionFactory: how to configure JNDI in Tomcat?

    - by EugeneP
    that's how the session factory should be gotten: protected SessionFactory getSessionFactory() { try { return (SessionFactory) new InitialContext() .lookup("SessionFactory"); } catch (Exception e) { } } Please provide a simple solution for Tomcat6 to be able to get SessionFactory thru simple jndi lookup in Java code. What should be written in what file on the side of Tomcat ?

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  • Jython saying "No visible constructors for class"

    - by clutch
    I have a jython servlet as part of a large application running in tomcat5. I tested a few Spring Framework classes and create the objects in the Jython servlet. When I try to create objects of classes in the application I catch an Exception message "No visible constructors for class". These java classes do have a public constructor class, such as: public SchoolImpl() { } I create the object in python: from com.dc.sports.entity import SchoolImpl ... school = SchoolImpl() What am I doing wrong?

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  • c++ dynamic_cast error handling

    - by Nazgob
    Is there any good practice related to dynamic_cast error handling (except not using it when you don't have to)? I'm wondering how should I go about NULL and bad_cast it can throw. Should I check for both? And if I catch bad_cast or detect NULL I probably can't recover anyway... For now, I'm using assert to check if dynamic_cast returned not NULL value. Would you accept this solution on a code review?

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  • Unable to add CRM 2011's Organization service as Service Reference to VS project

    - by Scorpion
    I have problem accessing Organization Service when I try to add it as a Service Reference in Visual Studio. However, I can Access the Service in browser. I have tried to add OrganizationData service and there is no issue with that. An Error occurred while attempting to find service at 'http://xxxxxxxx/xxxxx/XRMServices/2011/Organization.svc'. Error Details There was an error downloading 'http://xxxxxxxx/xxxxx/XRMServices/2011/Organization.svc/_vti_bin/ListData.svc/$metadata'. The request failed with HTTP status 400: Bad Request. Metadata contains a reference that cannot be resolved: 'http://xxxxxxxx/xxxxx/XRMServices/2011/Organization.svc'. Metadata contains a reference that cannot be resolved: 'http://xxxxxxxx/xxxxx/XRMServices/2011/Organization.svc'. If the service is defined in the current solution, try building the solution and adding the service reference again.

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  • Problem with tcp server when converting to service

    - by djerry
    Hello lads, I'm working on monitoring some object (cdr-packets). I'm setting up a tcp-server and am listening on port 50043 for the packages. The program as a console application is working just fine, my server is working like it should and i'm receiving the packets. When i try to use it as a service, i cannot seem to get a client connected to my server. Is there something i need to change to deploy this as a service? Code below is from my application: this is my service class where i start protected override void OnStart(string[] args) { server = new TcpServer(); server.StartServer(); } this is the constructor of TcpServer public TcpServer() { try { _server = new TcpListener(IPAddress.Any, 50043); } catch (Exception) { _server = null; } } this is the method i call after initialising the class public void StartServer() { if (_server != null) { // Create a ArrayList for storing SocketListeners before starting the server. _socketListenersList = new ArrayList(); // Start the Server and start the thread to listen client requests. _server.Start(); _serverThread = new Thread(new ThreadStart(ServerThreadStart)); _serverThread.Start(); // Create a low priority thread that checks and deletes client // SocktConnection objcts that are marked for deletion. _purgingThread = new Thread(new ThreadStart(PurgingThreadStart)); _purgingThread.Priority = ThreadPriority.Lowest; _purgingThread.Start(); } } this is the thread that keep checking if any client tries to connect private void ServerThreadStart() { // Client Socket variable; Socket clientSocket = null; TcpSocketListener socketListener = null; while (!_stopServer) { try { // Wait for any client requests and if there is any request from any //client accept it (Wait indefinitely). clientSocket = _server.AcceptSocket(); // Create a SocketListener object for the client. socketListener = new TcpSocketListener(clientSocket); // Add the socket listener to an array list in a thread safe fashon. lock (_socketListenersList) { _socketListenersList.Add(socketListener); } // Start a communicating with the client in a different thread. socketListener.StartSocketListener(); } catch (SocketException se) { _stopServer = true; } } } when for the first time a packet waits to be read, and i get to "clientSocket = _server.AcceptSocket();", it throws an exception (service, not very good debugable) Does anyone recognize this problem or can help me? Thanks in advance

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  • Python - List of Lists Slicing Behavior

    - by Dan Dobint
    When I define a list and try to change a single item like this: list_of_lists = [['a', 'a', 'a'], ['a', 'a', 'a'], ['a', 'a', 'a']] list_of_lists[1][1] = 'b' for row in list_of_lists: print row It works as intended. But when I try to use list comprehension to create the list: row = ['a' for range in xrange(3)] list_of_lists = [row for range in xrange(3)] list_of_lists[1][1] = 'b' for row in list_of_lists: print row It results in an entire column of items in the list being changed. Why is this? How can I achieve the desired effect with list comprehension?

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