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• Use a ContextLoaderListener in accordance with DispatchServlet

  - by Phuong Nguyen de ManCity fan

  I want to use both ContextLoaderListener (so that I can pass Spring Beans to my servlet) as well as DispatchServlet (Spring MVC). However, currently I have to pass init param to these both class initializer: <param-name>contextConfigLocation</param-name> <param-value> /WEB-INF/spring/app-config.xml </param-value> So, I use the same xml for these both classes. Wonder if it would lead to my beans being initialized twice? If yes, how would I do to avoid that?

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• PHP regular expression subpattern behaviour

  - by codecowboy

  I want to match both the src and title attributes of an image tag: pattern: <img [^>]*src=["|\']([^"|\']+["|\'])|title=["|\']([^"|\']+) target: <img src="http://someurl.jpg" class="quiz_caption" title="Caption goes here!"> This pattern gives me one unwanted match, title="content", and the match I actually want which is the value between the quotes after the word 'title', i.e 'content'. So, my matches are: <img src="http://someurl.jpg http://someurl.jpg title="Caption goes here!" Caption goes here! Is there a way to avoid the third of these matches? I'm using PCRE in PHP 5.2.x

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• Is there any tips for minimising access to a public page without login?

  - by alex

  I have a page that is just a non interactive display for a shop window. Obviously, I don't link to it, and I'd also like to avoid people stumbling across it (by Google etc). It will always be powered by Chrome. I have thought of... Checking User Agent for Chrome Ensuring resolution is 1920 x 1080 (not that useful as it is a client side check) Banning under robots.txt to keep Google out of it Do you have any more suggestions? Should I not really worry about it?

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• Persisting sensitve data in asp.net, odd implementation

  - by rawsonstreet

  For reasons not in scope of this question I have implemented a .net project in an iframe which runs from a classic asp page. The classic asp site persisted a few sensitive values by hitting the db on each page. I have passed there variables as xml to the aspx page, now I need to make these values available on any page of this .net site. I've looked into the cache object but we are on a web farm so I am not sure it would work. Is there a way I can can instantiate an object in a base page class and have other pages inherit from the base page to access these values? What is the best way to persist these values? A few more points to consider the site runs in https mode and I cannot use session variables, and I would like to avoid cookies if possible..

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• What are your references/recommendation on .NET DVDs, books and online training?

  - by egyamado

  There are lots of training methods from different vendors to learn .NET technologies (i.e. books, DVDs, online training, etc.). All of them claim the same thing: that they are the best, their content is 100% guaranteed, makes their customers professional in no time, etc. It’s confusing and sometimes frustrating as well. I especially want a training resource (i.e. a course) to provide valuable content in short time. More importantly I feel they should do their job properly so as to avoid the customer feeling they've wasted time or money. What I should do when I evaluating training methods and resources to help further software development skills? What are your training sources? Do you have any recommendations?

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• c++ polymorphism and other function question

  - by aharont

  i have got this code: class father{ public: virtual void f() { cout<<1;} }; class son:public father{ public: void f() {cout<<2;} }; void test (father x){x.f();} int main(){ son s; test(s); } the question says: the output is '1', what is the rule about polymorphism that the programmer forgot and how can i fix it so the output would be '2'? there is another rule that the programmer forgot when he wrote the father class, and he need to add an empty function to avoid problems from other sons of the father class. what is the rule and what is the missing function? another question write the g function so the next code would run with no crashes int x=11; g(x)=22;

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• How should I migrate DDL changes from one environment to the next?

  - by Rl

  I make DDL changes using SQL Developer's GUI. Problem is, I need to apply those same changes to the test environment. I'm wondering how others handle this issue. Currently I'm having to manually write ALTER statements to bring the test environment into alignment with the development environment, but this is prone to error (doing the same thing twice). In cases where there's no important data in the test environment I usually just blow everything away, export the DDL scripts from dev and run them from scratch in test. I know there are triggers that can store each DDL change, but this is a heavily shared environment and I would like to avoid that if possible. Maybe I should just write the DDL stuff manually rather than using the GUI?

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• MVC best practice when adding functions to controller?

  - by Patrick

  Hi I'm writing a function in my controller; this is supposed to take in a form, process it, register the user in DB, send a confirmation email etc etc. to avoid this function to be too cluttered, I was thinking of calling some sub-functions (eg: function registration() { //process form.. _insertInDb($formdata) _send_mail($address); //load confirmation view.. } function _send_mail($to) { //code here } function _insertInDb($formdata) { //other code here... } I'm not sure whether writing all the functions in the controller would be best practice -maybe I should insert all 'supporting' function (eg send_mail and insertInDb in this example) in another file and then import them? This would probably make the controller much more readable.. what's your view?

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• How to have NHibernate persist a String.Empty property value as NULL

  - by Todd

  I have a fairly simple class that I want to save to SQL Server via NHibernate (w/ Fluent mappings). The class is made up mostly of optional string fields. My problem is I default the class fields to string.empty to avoid NullRefExceptions and when NHibernate saves the row to the database each column contains an empty string instead of null. Question: Is there a way for me to get NHibernate to automatically save null when the string property is an empty string? Or do I need to litter my code with if (string.empty) checks?

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• Passing message over network

  - by Sylvestre Equy

  Hi, I'm currently trying to develop a message-oriented networking framework and I'm a bit stuck on the internal mechanism. Here are the problematic interfaces : public interface IMessage { } public class Connection { public void Subscribe<TMessage>(Action<TMessage> messageCallback); public void Send<TMessage>(TMessage message); } The Send method does not seem complicated, though the mechanism behind Subscribe seems a bit more painful. Obviously when receiving a message on one end of the connection, I'll have to invoke the appropriate delegate. Do you have any advice on how to read messages and easily detect their types ? By the way, I'd like to avoid to use MSMQ.

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• SVN - ignoring files already in repository

  - by Alex

  I have a configuration file in my project which needs to be in the repository (so new developers get it when they checkout the project). Each developer might change some values in the file locally - these changes should not be committed and I don't want them showing in the synchronization menu (I'm using eclipse and subversive if it matters). Note that I can't just set the svn:ignore property since it only works on files that aren't under version control - but I do want to keep a base version of the file in the repository. How can I avoid the file showing in synchronization without deleting it from repository? EDIT: A better description - what I actually need is to be able to set a "read-only" property on the config file, so it can't be changed in the repository as long as the property is on. Do you know anything like this? Thanks

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• What's the easiest way to implement background downloading in Wicket?

  - by David Moles

  I've got a simple Wicket form that lets users select some data and then download a ZIP file (generated on the fly) containing what they asked for. Currently the form button's onSubmit() method looks something like this: public void onSubmit() { IResourceStream stream = /* assemble the data they asked for ... */ ; ResourceStreamRequestTarget target = new ResourceStreamRequestTarget(stream); target.setFileName("download.zip"); RequestCycle.get().setRequestTarget(target); } This works, but of course the request stops there and it's impossible to display any other feedback to the user. What I'd like to have is something like the typical "Your requested download [NAME] should begin automatically. If not, click this link." Ideally, still displaying the same page, so the user can immediately select some different data and download that as well. I imagine it's possible to do this using Wicket's Ajax classes, but I've managed to avoid having to use them so far, and it's not immediately obvious to me how. What's my quickest way out, here?

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• Rails Variable across all controller actions

  - by bob

  Hello, This should be a very simple rails question. I have a variable like the following. @administration = Administration.first I want this variable to be accessible through every controller action across all my controllers so for example if I have a Product controller and inside of it I have the usual CRUD actions, I want the @administration variable as defined above to be put into all the CRUD actions. (It would not be needed in destroy or create or update). I have many controllers throughout my project and I was wondering if there is an easier way than adding it manually through all of the actions that I want it in. I tried a global variable $administration = Administration.first but I run into an issue where it is not updated when I update the actual content of the Administration.first table. Also, I would like to avoid global variables. Any help would be much appreciated. Thanks! :)

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• What happens to an instance of ServerSocket blocked inside accept(), when I drop all references to i

  - by Hanno Fietz

  In a multithreaded Java application, I just tracked down a strange-looking bug, realizing that what seemed to be happening was this: one of my objects was storing a reference to an instance of ServerSocket on startup, one thread would, in its main loop in run(), call accept() on the socket while the socket was still waiting for a connection, another thread would try to restart the component under some conditions, the restart process missed the cleanup sequence before it reached the initialization sequence as a result, the reference to the socket was overwritten with a new instance, which then wasn't able to bind() anymore the socket which was blocking inside the accept() wasn't accessible anymore, leaving a complete shutdown and restart of the application as the only way to get rid of it. Which leaves me wondering: with no references left to the ServerSocket instance, what would free the socket for a new connection? At what point would the ServerSocket become garbage collected? In general, what are good practices I can follow to avoid this type of bug?

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• Creating and releasing objects in the same method, while using self as delegate

  - by user200341

  In objective-c you are responsible for releasing objects you allocate, but what happens when you allocate an object in a method, assign self as the objects delegate, and then release the object. The callbacks from the newly created (and released) object fails at this point, or rather, doesn't happen. - (void)doSomething { MyObj *myObj = [[MyObj alloc] init]; myObj.delegate = self; [myObj performOperation]; [myObj release]; } - (void)callbackMethodFromMyObj:(NSString *)message { NSLog(message); } I can't release the object until the callback has occurred, and I can't avoid releasing the object in the same method that creates it (because it exists outside the scope). One way of doing it would be to pass the object along in the call-back and release it in the callback, but is this the right way to go about this?

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• database row/ record pointers

  - by David

  Hi I don't know the correct words for what I'm trying to find out about and as such having a hard time googling. I want to know whether its possible with databases (technology independent but would be interested to hear whether its possible with Oracle, MySQL and Postgres) to point to specific rows instead of executing my query again. So I might initially execute a query find some rows of interest and then wish to avoid searching for them again by having a list of pointers or some other metadata which indicates the location on a database which I can go to straight away the next time I want those results. I realise there is caching on databases, but I want to keep these "pointers" else where and as such caching doesn't ultimately solve this problem. Is this just an index and I store the index and look up by this? most of my current tables don't have indexes and I don't want the speed decrease that sometimes comes with indexes. So whats the magic term I've been trying to put into google? Cheers

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• UITableView with contact image problems.

  - by prathumca

  As par my app requirement, I'm showing the contact images in a UITableView as shown below. ABRecordRef contact = [self getContact]; if(contact && ABPersonHasImageData(contact)) { UIImage *contactImage = [UIImage imageWithData:(NSData*)ABPersonCopyImageData(contact)]; callImage.image = contactImage; } I've two problems if I use the above code segment. Table Scrolling is too slow. If comment the above code, then UITable responds very fast. Memory Management. My app started using 25 - 30 MB of RAM. Is there any better way to avoid the above two problems?

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• Hibernate Unit tests - Reset schema

  - by Marco

  Hi, I'm testing the CRUD operations of my DAOs in JUnit tests. When i execute the single test, Hibernate always resets the schema and populates the DB in a known state. But when i execute multiple tests in a row, Hibernate resets the schema once, and then the data is accumulated during the execution of the tests. This is an unexpected behavior, so I'd like to add in the @Before method of the tests a function that explicitly resets the schema to avoid the pesistence of side data created by previous tests during the execution chain. Any tips? Thanks

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• [C#] How to create a constructor of a class that return a collection of instances of that class?

  - by codemonkie

  My program has the following class definition: public sealed class Subscriber { private subscription; public Subscriber(int id) { using (DataContext dc = new DataContext()) { this.subscription = dc._GetSubscription(id).SingleOrDefault(); } } } ,where _GetSubscription() is a sproc which returns a value of type ISingleResult<_GetSubscriptionResult> Say, I have a list of type List<int> full of 1000 ids and I want to create a collection of subscribers of type List<Subscriber>. How can I do that without calling the constructor in a loop for 1000 times? Since I am trying to avoid switching the DataContext on/off so frequently that may stress the database. TIA.

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• Accessing php $_SESSION from python (wsgi) - is it possible?

  - by Bill Zimmerman

  Hi, I've got a python/WSGI app which needs to check to see if a user has logged on to a PHP web app. The problem is that the PHP app checks if a user has logged on by comparing a value in the $_SESSION variable to a value in the cookie from the user's browser. I would prefer to avoid changing the behavior of the php app if at all possible. My questions: Is there anyway I can access the session variables from within python? Where should I start to look? Are there any obvious security/performance issues I should be aware of when taking this approach?

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• Is it a good practice to create a reference to application context and use it anywhere?

  - by kknight

  I have to use context in many places of my code such as database operations, preference operations, etc. I don't want to pass in context for every method. Is it a good practice to create a reference to application context at the main Activity and use it anywhere such as database operations? So, I don't need some many context in method parameters, and the code can avoid position memory leak due to use of Activity Context. public class MainActivity extends Activity { public static Context s_appContext; /** Called when the activity is first created. */ @Override public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); s_appContext = this.getApplicationContext();

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• Refresh combo box in Windows Form VB.NET

  - by fireBand

  Following is the code to populate combobox using DataSource Dim CountryList As Array = MyCtrl.GetAllCountries With cbCountyList .DataSource = CountryList .DisplayMember = "CountryName" .ValueMember = "CountryID" End With After adding a new COuntry Name to Database I want to reflect the changes in combobox. Repeating this code is not an option becasue it triggers SelectIndexChange event and had to do some crappy work around to avoid that. So I was wondering if there is way to refresh the combobox list. I actually thought binding with the DataSource property supposed to do it automatically. I also tried cbCountyList.Refresh() Thanks in advance.

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• Can I have fixed typed ArrayList in C#, just like C++?

  - by Kazoom

  I have an ArrayList which contains fixed type of objects. However everytime I need to extract an object a particular index, I need to typecast it to my user defined type from object type. Is there a way in C# to declare ArrayList of fixed types just like Java and C++, or is there a work around to avoid the typecasting everytime? Edit: I apologize I forgot mentioning that I require the datastructure to be thread-safe, which List is not. Otherwise I would have just used a normal Array. But I want to save myself from the effort of explicitly locking and unlocking while writing the array. So I thought of using ArrayList, synchronize it, but it requires typecasting every time.

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• Cakephp ajax Autocomplete not working

  - by Vijay Kumbhar

  Hello All, I am using ajax autocomplete in my application, but it is not giving the output. Ajax request to the desired function goes but it is not giving back any response, it is blank. I am also using jquery but it is used for other effects. i added jquery no conflict to avoid the prototype & jquery conflicts. I have tried other ajax helper methods like obeserverfield, it is working fine & returning the proper response, but when i use autocomplete it fails Can anybody help me ..........

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• IntelliJ Split Window Navigation

  - by jmquigley

  If I split the editor window (horizontal or vertical) into N tab groups, how do I switch/toggle from one tab group to another via the keyboard? If all of the tabs are in the same group you can switch from each tab easily (CTRL + right/left arrow), but when they're in separate tab groups I can't. I've searched through the key mappings and have not found one that seems to accomplish this. I know I can use the mouse, but I'm trying to find ways to avoid the mouse and stay with the keyboard. TIA for any help on this.

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