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• iOS6: do we have to set rootViewController in App delegate in order to support different orientations?

  - by Centurion

  The app was perfectly fine working in iOS5 in landscape orientation. However in iOS6, it started to use portrait orientation in all view controllers. The methods shouldAutorotateToInterfaceOrientation are not called anymore. I read the new stuff about changed rotation mechanism in iOS6 and I was able to fix that by adding a line in my AppDelegate: self.window.rootViewController = _viewController _viewControler is the starting screen (Home-menu). All other view controllers implement shouldAutorotateToInterfaceOrientation method and returns YES for landscape orientations only. So, it's perfectly working solution for the app that needs to support only one orientation. However, the problem is I need one view controller (lets call it phone-VC) to be presented in portrait orientation. Now, if I want this view controller would be rotated then I need to return YES in Home-menu controller that is assigned to rootViewControler in appDelegate. However, I can't do that because this rootViewController is starting window that need to presented in landscape only, otherwise the layout with graphics in this window will break. But if I don't return YES from its shouldAutorotateToInterfaceOrientation (Home-menu) then the same method is not called in my view phone-VC that needs to be presented in portrait. Any ideas? Does the assignation of rootViewController is mandatory in AppDelegate? UPDATE: the problem exists on device (at least on iPhone4).

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• C#: Need one of my classes to trigger an event in another class to update a text box

  - by Matt

  Total n00b to C# and events although I have been programming for a while. I have a class containing a text box. This class creates an instance of a communication manager class that is receiving frames from the Serial Port. I have this all working fine. Every time a frame is received and its data extracted, I want a method to run in my class with the text box in order to append this frame data to the text box. So, without posting all of my code I have my form class... public partial class Form1 : Form { CommManager comm; public Form1() { InitializeComponent(); comm = new CommManager(); } private void updateTextBox() { //get new values and update textbox } . . . and I have my CommManager class class CommManager { //here we manage the comms, recieve the data and parse the frame } SO... essentially, when I parse that frame, I need the updateTextBox method from the form class to run. I'm guessing this is possible with events but I can't seem to get it to work. I tried adding an event handler in the form class after creating the instance of CommManager as below... comm = new CommManager(); comm.framePopulated += new EventHandler(updateTextBox); ...but I must be doing this wrong as the compiler doesn't like it... Any ideas?!

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• interface variables are final and static by default and methods are public and abstract

  - by sap

  The question is why it's been decided to have variable as final and static and methods as public and abstract by default. Is there any particular reason for making them implicit,variable as final and static and methods as public and abstract. Why they are not allowing static method but allowing static variable? We have interface to have feature of multiple inheritance in Java and to avoid diamond problem. But how it solves diamond problem,since it does not allow static methods. In the following program, both interfaces have method with the same name..but while implementing only one we implement...is this how diamond problem is solved? interface testInt{ int m = 0; void testMethod(); } interface testInt1{ int m = 10; void testMethod(); } public class interfaceCheck implements testInt, testInt1{ public void testMethod(){ System . out . println ( "m is"+ testInt.m ); System . out . println ( "Hi World!" ); } }

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• Should a C++ constructor do real work?

  - by Wade Williams

  I'm strugging with some advice I have in the back of my mind but for which I can't remember the reasoning. I seem to remember at some point reading some advice (can't remember the source) that C++ constructors should not do real work. Rather, they should initialize variables only. The advice when on to explain that real work should be done in some sort of init() method, to be called separately after the instance was created. The situation is I have a class that represents a hardware device. It makes logical sense to me for the constructor to call the routines that query the device in order to build up the instance variables that describe the device. In other words, once new instantiates the object, the developer receives an object which is ready to be used, no separate call to object-init() required. Is there a good reason why constructors shouldn't do real work? Obviously it could slow allocation time, but that wouldn't be any different if calling a separate method immediately after allocation. Just trying to figure out what gotchas I not currently considering that might have lead to such advice.

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• How to use observer_field in RoR?

  - by Sindri Guðmundsson

  Hi, I have a single select_tag with categories gathered from array in controller. When the user selects a category I want the application to redirect to the selected category. I have the following code in my view which. (I've tried both using :method = :get and :post, only change is in development.log) <%=select_tag "cat_selected", options_for_select(@cats_for_mt)%><br> <%=observe_field 'cat_selected', :url => {:action => :viewflokkur}, :with => 'cat', :method => :get %> When I select one of the options the following gets logged to development.log. Processing CategoriesController#viewflokkur (for 127.0.0.1 at 2010-06-12 12:33:26) [GET] Parameters: {"cat"=>"Taugasjúkraþjálfun", "authenticity_token"=> "B2u5ULNr7IJ/ta0+hiAMBjmjEtTtc/yMAQQvSxFn2d0="} Rendering template within layouts/main Rendering categories/viewflokkur Completed in 20ms (View: 18, DB: 0) | 200 OK [http://localhost/categories/viewflokkur?cat=Taugasj%C3%BAkra%C3%BEj%C3%A1lfun&authenticity_token=B2u5ULNr7IJ%2Fta0%2BhiAMBjmjEtTtc%2FyMAQQvSxFn2d0%3D] According to this I should now be in "viewflokkur", but nothing changes in the browser window. Is there anything else I need to do, maybe in the controller? BR, Sindri

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• calling same function on different buttons not loaded yet

  - by Jordan Faust

  I can not get this to work for every button and I cannot find anything explaining why. I guessing it is something small that I am missing $(document).ready(function() { // delete the selected row from the database $(document).on('click', '#business-area-delete-button', { model: "BusinessArea" }, deleteRow); $(document).on('click', '#business-type-delete-button', { model: "BusinessType" }, deleteRow); $(document).on('click', '#client-delete-button', { model: "Client" }, deleteRow); $(document).on('click', '#client-type-delete-button', { model: "ClientType" }, deleteRow); $(document).on('click', '#communication-channel-type', { model: "CommunicationChannelType" }, deleteRow); $(document).on('click', '#parameter-type-delete-button', { model: "ParameterType" }, deleteRow); $(document).on('click', '#validation-method-delete-button', { model: "ValidationMethod" }, deleteRow); } the event function deleteRow(event){ $.ajax( { type:'POST', data: { id: $(".delete-row").attr("id") }, url:"/mysite/admin/delete" + event.data.model, success:function(data,textStatus){ $('#main-content').html(data); }, error:function(XMLHttpRequest,textStatus,errorThrown){ jQuery('#alerts').html(XMLHttpRequest.responseText); }, complete:function(XMLHttpRequest,textStatus){ placeAlerts() } } ); return false }; This works only for a the button with id validation-method-delete-button. I use document and not the button its self because the button is contained in a template that is loaded later via ajax. I have this working for a similar function that is selecting a row in a table however I am not attempting to pass data in that scenario.

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• Help with create action in a different show page

  - by Andrew

  Hi, I'm a Rails newbie and want to do something but keep messing something up. I'd love some help. I have a simple app that has three tables. Users, Robots, and Recipients. Robots belong_to users and Recipients belong_to robots. On the robot show page, I want to be able to create recipients for that robot right within the robot show page. I have the following code in the robot show page which lists current recipients: <table> <% @robot.recipients.each do |recipient| %> <tr> <td><b><%=h recipient.chat_screen_name %></b> via <%=h recipient.protocol_name</td> <td><%= link_to 'Edit', edit_recipient_path(recipient) %>&nbsp;</td> <td><%= link_to 'Delete', recipient, :confirm => 'Are you sure?', :method => :delete %></td> </tr> <% end %> </table> What I'd like to do is have an empty field in which the user can add a new recipient, and have tried the following: I added this to the Robots Show view: <% form_for(@robot.recipient) do |f| %> Enter the screen name<br> <%= f.text_field :chat_screen_name %> <p> <%= f.submit 'Update' %> </p> <% end %> and then this to the Robot controller in the show action: @recipient = Recipient.new @recipients = Recipient.all Alas, I'm still getting a NoMethod error that says: "undefined method `recipient' for #" I'm not sure what I'm missing. Any help would be greatly appreciated. Thank you.

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• OOP/MVC advice on where to place a global helper function

  - by franko75

  Hi, I have a couple of controllers on my site which are handling form data. The forms use AJAX and I have quite a few methods across different controllers which are having to do some specific processing to return errors in a JSON encoded format - see code below. Obviously this isn't DRY and I need to move this code into a single helper function which I can use globally, but I'm wondering where this should actually go! Should I create a static helper class which contains this function (e.g Validation::build_ajax_errors()), or as this code is producing a format which is application specific and tied into the jQuery validation plugin I'm using, should it be a static method stored in, for example, my main Website controller which the form handling controllers extend from? //if ajax request, output errors if (request::is_ajax()) { //need to build errors into array form for javascript validation - move this into a helper method accessible globally $errors = $post->errors('form_data/form_error_messages'); $i = 0; $new_errors = array(); foreach ($errors as $key => $value) { $new_errors[$i][0] = '#' . $key; $new_errors[$i][1] = $value; $new_errors[$i][2] = "error"; $i++; } echo '{"jsonValidateReturn":' . json_encode($new_errors) . '}'; return; }

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• Entity framework with Linq to Entities performance

  - by mare

  If I have a static method like this public static string GetTicClassificationTitle(string classI, string classII, string classIII) { using (TicDatabaseEntities ticdb = new TicDatabaseEntities()) { var result = from classes in ticdb.Classifications where classes.ClassI == classI where classes.ClassII == classII where classes.ClassIII == classIII select classes.Description; return result.FirstOrDefault(); } } and use this method in various places in foreach loops or just plain calling it numerous times, does it create and open new connection every time? If so, how can I tackle this? Should I cache the results somewhere, like in this case, I would cache the entire Classifications table in Memory Cache? And then do queries vs this cached object? Or should I make TicDatabaseEntities variable static and initialize it at class level? Should my class be static if it contains only static methods? Because right now it is not.. Also I've noticed that if I return result.First() instead of FirstOrDefault() and the query does not find a match, it will issue an exception (with FirstOrDefault() there is no exception, it returns null). Thank you for clarification.

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• Submit a form and get a JSON response with jQuery

  - by Leopd

  I expect this is easy, but I'm not finding a simple explanation anywhere of how to do this. I have a standard HTML form like this: <form name="new_post" action="process_form.json" method=POST> <label>Title:</label> <input id="post_title" name="post.title" type="text" /><br/> <label>Name:</label><br/> <input id="post_name" name="post.name" type="text" /><br/> <label>Content:</label><br/> <textarea cols="40" id="post_content" name="post.content" rows="20"></textarea> <input id="new_post_submit" type="submit" value="Create" /> </form> I'd like to have javascript (using jQuery) submit the form to the form's action (process_form.json), and receive a JSON response from the server. Then I'll have a javascript function that runs in response to the JSON response, like function form_success(json) { alert('Your form submission worked'); // process json response } How do I wire up the form submit button to call my form_success method when done? Also it should override the browser's own navigation, since I don't want to leave the page. Or should I move the button out of the form to do that?

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• OrderBy Linq.Expression as parameter = (Of Func(Of T,IComparable)) to perform LinqToEntity is not working

  - by NicoJuicy

  I'd like to get this working: Call: (Count & Page are used for pagination, so Count = 20 and Page = 1 for example, for the first 20 values). Sorting should be by name LeverancierService.GetLeveranciers(Function(el) el.Name, Count, Page) Equivalent in c#: LeverancierService.GetLeveranciers(el= el.Name, Count, Page) Method that gives an error (parameters shown above): Public Overridable Function GetAllPaged(orderby As Expression(Of Func(Of T, IComparable)), ByVal Count As Integer, ByVal Page As Integer) As IEnumerable(Of T) Return dbset.OrderBy(orderby).Skip((Page - 1) * Count).Take(Count).ToList() End Function Already tried changing it to this, but it gives the same error: Public Overridable Function GetAllPaged(Of TOrderBy)(orderby As Expression(Of Func(Of T, TOrderBy)), ByVal Count As Integer, ByVal Page As Integer) As IEnumerable(Of T) Return dbset.OrderBy(orderby).Skip((Page - 1) * Count).Take(Count).ToList() End Function Error: Unable to cast the type 'System.String' to type 'System.IComparable'. LINQ to Entities only supports casting Entity Data Model primitive types. Any idea how to do this? Extra info: I'm in a DDD-layered application, so the parameter should stay the same as the called method is an overridden interface (eg. if i change this, i have to do this for 200 times or so, because it's in VB.Net and not in C# (= 1 change) ) I know there is a way to change the expression to a string and then use DLinq (= Dynamic Linq), but that's not how it should be.

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• Django Model Formset Pre-Filled Value Problem

  - by user552377

  Hi, i'm trying to use model formsets with Django. When i load forms template, i see that it's filled-up with previous values. Is there a caching mechanism that i should stop, or what? Thanks for your help, here is my code: models.py class FooModel( models.Model ): a_field = models.FloatField() b_field = models.FloatField() def __unicode__( self ): return self.a_field forms.py from django.forms.models import modelformset_factory FooFormSet = modelformset_factory(FooModel) views.py def foo_func(request): if request.method == 'POST': formset = FooFormSet(request.POST, request.FILES, prefix='foo_prefix' ) if formset.is_valid(): formset.save() return HttpResponseRedirect( '/true/' ) else: return HttpResponseRedirect( '/false/' ) else: formset = FooFormSet(prefix='foo_prefix') variables = RequestContext( request , { 'formset':formset , } ) return render_to_response('footemplate.html' , variables ) template: <form method="post" action="."> {% csrf_token %} <input type="submit" value="Submit" /> <table id="FormsetTable" border="0" cellpadding="0" cellspacing="0"> <tbody> {% for form in formset.forms %} <tr> <td>{{ form.a_field }}</td> <td>{{ form.b_field }}</td> </tr> {% endfor %} </tbody> </table> {{ formset.management_form }} </form>

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• Please help with IFrame callback

  - by Code Sherpa

  Hi - thanks for clicking. I am trying to get status feedback using an IFrame for file uploads. I am not trying to get progress or percentages - just when a file is done uploading and if it was a success or failure. THE PROBLEM is that I can't seem to get the server response to appear on the client. I have to following design: I have an iframe on my page: <iframe id="target_frame" src="" style="border:0px; width:0px; height:0px"></iframe> The form tag points to it: <form enctype="multipart/form-data" id="fileUploadForm" name="fileUploadForm" action="picupload.aspx" method="post" target="target_frame"> And the submit button starts a file upload via the iframe: <input id="submit" type="submit" value="upload" /> In the picupload.aspx.cs file, I have a method that returns dynamic data. I then send it to the client: message = data; Response.Write(String.Format("<script language='javascript' type='text/javascript'>window.parent.handleResponse('{0}');</script>", message)); On the client, I have a response handler: function handleResponse(msg) { document.getElementById('statusDiv').innerHTML = msg; } My intent is to see the msg value change for each uploaded file but I never see anything appear in statusDiv, let alone dynamically changing messages. Can somebody please help??

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• How to specify multiple values in where with AR query interface in rails3

  - by wkhatch

  Per section 2.2 of rails guide on Active Record query interface here: which seems to indicate that I can pass a string specifying the condition(s), then an array of values that should be substituted at some point while the arel is being built. So I've got a statement that generates my conditions string, which can be a varying number of attributes chained together with either AND or OR between them, and I pass in an array as the second arg to the where method, and I get: ActiveRecord::PreparedStatementInvalid: wrong number of bind variables (1 for 5) which leads me to believe I'm doing this incorrectly. However, I'm not finding anything on how to do it correctly. To restate the problem another way, I need to pass in a string to the where method such as "table.attribute = ? AND table.attribute1 = ? OR table.attribute1 = ?" with an unknown number of these conditions anded or ored together, and then pass something, what I thought would be an array as the second argument that would be used to substitute the values in the first argument conditions string. Is this the correct approach, or, I'm just missing some other huge concept somewhere and I'm coming at this all wrong? I'd think that somehow, this has to be possible, short of just generating a raw sql string.

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• Java, Massive message processing with queue manager (trading)

  - by Ronny

  Hello, I would like to design a simple application (without j2ee and jms) that can process massive amount of messages (like in trading systems) I have created a service that can receive messages and place them in a queue to so that the system won't stuck when overloaded. Then I created a service (QueueService) that wraps the queue and has a pop method that pops out a message from the queue and if there is no messages returns null, this method is marked as "synchronized" for the next step. I have created a class that knows how process the message (MessageHandler) and another class that can "listen" for messages in a new thread (MessageListener). The thread has a "while(true)" and all the time tries to pop a message. If a message was returned, the thread calls the MessageHandler class and when it's done, he will ask for another message. Now, I have configured the application to open 10 MessageListener to allow multi message processing. I have now 10 threads that all time are in a loop. Is that a good design?? Can anyone reference me to some books or sites how to handle such scenario?? Thanks, Ronny

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• C#: Populating a UI using separate threads.

  - by Andrew

  I'm trying to make some sense out of an application Ive been handed in order to track down the source of an error. Theres a bit of code (simplified here) which creates four threads which in turn populate list views on the main form. Each method gets data from the database and retrieves graphics from a resource dll in order to directly populate an imagelist and listview. From what Ive read on here (link) updating UI elements from any thread other than the UI thread should not be done, and yet this appears to work? Thread t0 = new Thread(new ThreadStart(PopulateListView1)); t0.IsBackground = true; t0.Start(); Thread t1 = new Thread(new ThreadStart(PopulateListView2)); t1.Start(); Thread t2 = new Thread(new ThreadStart(PopulateListView3)); t2.Start(); Thread t3 = new Thread(new ThreadStart(PopulateListView4)); t3.Start(); The error itself is a System.InvalidOperationException "Image cannot be added to the ImageList." which has me wondering if the above code is linked in some way. Iis this method of populating the UI recommended and if not what are the possible complications resulting from it?

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• When to use @Singleton in a Jersey resource

  - by dexter

  I have a Jersey resource that access the database. Basically it opens a database connection in the initialization of the resource. Performs queries on the resource's methods. I have observed that when I do not use @Singleton, the database is being open at each request. And we know opening a connection is really expensive right? So my question is, should I specify that the resource be singleton or is it really better to keep it at per request especially when the resource is connecting to the database? My resource code looks like this: //Use @Singleton here or not? @Path(/myservice/) public class MyResource { private ResponseGenerator responser; private Log logger = LogFactory.getLog(MyResource.class); public MyResource() { responser = new ResponseGenerator(); } @GET @Path("/clients") public String getClients() { logger.info("GETTING LIST OF CLIENTS"); return responser.returnClients(); } ... // some more methods ... } And I connect to the database using a code similar to this: public class ResponseGenerator { private Connection conn; private PreparedStatement prepStmt; private ResultSet rs; public ResponseGenerator(){ Class.forName("org.h2.Driver"); conn = DriverManager.getConnection("jdbc:h2:testdb"); } public String returnClients(){ String result; try{ prepStmt = conn.prepareStatement("SELECT * FROM hosts"); rs = prepStmt.executeQuery(); ... //do some processing here ... } catch (SQLException se){ logger.warn("Some message"); } finally { rs.close(); prepStmt.close(); // should I also close the connection here (in every method) if I stick to per request // and add getting of connection at the start of every method // conn.close(); } return result } ... // some more methods ... } Some comments on best practices for the code will also be helpful.

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• Android: Problems downloading images and converting to bitmaps

  - by Mike

  Hi all, I am working on an application that downloads images from a url. The problem is that only some images are being correctly downloaded and others are not. First off, here is the problem code: public Bitmap downloadImage(String url) { HttpClient client = new DefaultHttpClient(); HttpResponse response = null; try { response = client.execute(new HttpGet(url)); } catch (ClientProtocolException cpe) { Log.i(LOG_FILE, "client protocol exception"); return null; } catch (IOException ioe) { Log.i(LOG_FILE, "IOE downloading image"); return null; } catch (Exception e) { Log.i(LOG_FILE, "Other exception downloading image"); return null; } // Convert images from stream to bitmap object try { Bitmap image = BitmapFactory.decodeStream(response.getEntity().getContent()); if(image==null) Log.i(LOG_FILE, "image conversion failed"); return image; } catch (Exception e) { Log.i(LOG_FILE, "Other exception while converting image"); return null; } } So what I have is a method that takes the url as a string argument and then downloads the image, converts the HttpResponse stream to a bitmap by means of the BitmapFactory.decodeStream method, and returns it. The problem is that when I am on a slow network connection (almost always 3G rather than Wi-Fi) some images are converted to null--not all of them, only some of them. Using a Wi-Fi connection works perfectly; all the images are downloaded and converted properly. Does anyone know why this is happening? Or better, how can I fix this? How would I even go about testing to determine the problem? Any help is awesome; thank you!

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• access properties of current model in has_many declaration

  - by seth.vargo

  Hello, I didn't exactly know how to pose this question other than through example... I have a class we will call Foo. Foo :has_many Bar. Foo has a boolean attribute called randomize that determines the order of the the Bars in the :has_many relationship: class CreateFoo < ActiveRecord::Migration def self.up create_table :foos do |t| t.string :name t.boolean :randomize, :default => false end end end   class CreateBar < ActiveRecord::Migration def self.up create_table :bars do |t| t.string :name t.references :foo end end end   class Bar < ActiveRecord::Base belongs_to :foo end   class Foo < ActiveRecord::Base # this is the line that doesn't work has_many :bars, :order => self.randomize ? 'RAND()' : 'id' end How do I access properties of self in the has_many declaration? Things I've tried and failed: creating a method of Foo that returns the correct string creating a lambda function crying Is this possible? UPDATE The problem seems to be that the class in :has_many ISN'T of type Foo: undefined method `randomize' for #<Class:0x1076fbf78> is one of the errors I get. Note that its a general Class, not a Foo object... Why??

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• Generic that takes only numeric types (int double etc)?

  - by brandon

  In a program I'm working on, I need to write a function to take any numeric type (int, short, long etc) and shove it in to a byte array at a specific offset. There exists a Bitconverter.GetBytes() method that takes the numeric type and returns it as a byte array, and this method only takes numeric types. So far I have: private void AddToByteArray<T>(byte[] destination, int offset, T toAdd) where T : struct { Buffer.BlockCopy(BitConverter.GetBytes(toAdd), 0, destination, offset, sizeof(toAdd)); } So basically my goal is that, for example, a call to AddToByteArray(array, 3, (short)10) would take 10 and store it in the 4th slot of array. The explicit cast exists because I know exactly how many bytes I want it to take up. There are cases where I would want a number that is small enough to be a short to really take up 4 bytes. On the flip side, there are times when I want an int to be crunched down to just a single byte. I'm doing this to create a custom network packet, if that makes any ideas pop in to your heads. If the where clause of a generic supported something like "where T : int || long || etc" I would be ok. (And no need to explain why they don't support that, the reason is fairly obvious) Any help would be greatly appreciated! Edit: I realize that I could just do a bunch of overloads, one for each type I want to support... but I'm asking this question because I want to avoid precisely that :)

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• Problem with ModelAndView and ModelMap in AnnotationController, Springframework

  - by saltfactory

  I have a question that is a point difference between ModelAndView and ModelMap. I want to maintain modelAndView when requestMethod is "GET" and requestMethod is "POST". My modelAndView saved others. So I made modelAndView return type to "GET", "POST" methods. But, Request lost commandObject, form:errors..., if request return showForm on "POST" because request validation failed. example) private ModelAndView modelAndView; public ControllerTest{ this.modelAndView = new ModelAndView(); } @RequestMapping(method = RequestMethod.GET) public ModelAndView showForm(ModelMap model) { EntityObject entityObject = new EntityObject(); CommandObject commandObject = new CommandObject(); commandObject.setEntityObject(entityObject); model.addAttribute("commandObject", commandObject); this.modelAndView.addObject("id", "GET"); this.modelAndView.setViewName("registerForm"); return this.modelAndView; } @RequestMapping(method = RequestMethod.POST) public ModelAndView submit(@ModelAttribute("commandObject") CommandObject commandObject, BindingResult result, SessionStatus status) { this.commandValidator.validate(commandObject, result); if (result.hasErrors()) { this.modelAndView.addObject("id", "POST"); this.modelAndView.setViewName("registerForm"); return this.modelAndView; } else { this.modelAndView.addObject("id", "after POST"); this.modelAndView.setViewName("success"); } status.setComplete(); return this.modelAndView; }

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• Ensure that my C# desktop application is making requests to my ASP .NET MVC action?

  - by Mathias Lykkegaard Lorenzen

  I've seen questions that are almost identical to this one, except minor but important differences that I would like to get detailed. Let's say that I have a controller and an action method in MVC which therefore accepts requests on the following URL: http://example.com/api/myapimethod?data=some-data-here. This URL is then being called regularly by 1000 clients or more spread out in the public. The reason for this is crowdsourcing. The clients around the globe help feed a global cache on my server, which makes it faster for the rest of the clients to fetch the data. Now, if I'm sneaky (and I am), I can go into Fiddler, Ethereal, Wireshark or any other packet sniffing tool and figure out which requests the program is making. By figuring that out, I can also replicate them, and fill the service with false corrupted data. What is the best approach to ensuring that the data received in my ASP .NET MVC action method is actually from the desktop client application, and not some falsely generated data that the user invented? Since it is all based on crowdsourcing, would it be a good idea for my users to be able to "vote" if some data is falsified, and then let an automatic cleanup commence if there are enough votes? I do not have access to a tool like SmartAssembly, so unfortunately my .NET program is fully decompilable. I realize this might be impossible to accomplish in an error-proof manner, but I would like to know where my best chances are.

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• Compile for mixed platform (32, 64) and reference a 32 or 64 bit DLL resolved at runtime

  - by Nigel Aston

  Using VS2010 under windows 32 or 64 bit. Our C# app calls a 3rd party DLL (managed) that interfaces to an unmanaged DLL. The 3rd party DLL API appears identical in 32 or 64 bit although underneath it links to a 32 or 64 bit unmanaged DLL. We want our C# app to run on either 32 or 64 bit OS, ideally it will auto detect the OS and load the appropriate 32rd party DLL - via a simple factory class which tests the Enviroment. So the neatest solution would be a runtime folder containing: OurApp.exe 3rdParty32.DLL 3rdPartyUnmanaged32.DLL 3rdParty64.DLL 3rdPartyUnmanaged64.DLL However, the interface for the managed 3rdParty 32 and 64 dll is identical so both cannot be referenced within the same VS2010 project: when adding the second the warning triangle is shown and it does not get referenced. Is my only answer to create two extra library DLL projects to reference the 3rdParty 32 and 64 Dlls? So I would end up with this project arrangement: Project 1: Builds OurApp.exe, dynamically creates an object for project2 or project3. Project 2: Builds OurApp32.DLL which references 3rdParty32.dll Project 3: Builds OurApp64.DLL which references 3rdParty64.dll

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• Cant access NString after callback in [NSURLConnection sendSynchronousRequest]

  - by John ClearZ

  Hi I am trying to get a cookie from a site which I can do no problem. The problem arises when I try and save the cookie to a NSString in a holder class or anywhere else for that matter and try and access it outside the delegate method where it is first created. - (void)connection:(NSURLConnection *)connection didReceiveResponse:(NSURLResponse *)response { int i; NSString* c; NSArray* all = [NSHTTPCookie cookiesWithResponseHeaderFields:[response allHeaderFields] forURL:[NSURL URLWithString:@"http://johncleary.net"]]; //NSLog(@"RESPONSE HEADERS: \n%@", [response allHeaderFields]); for (i=0;i<[all count];i++) { NSHTTPCookie* cc = [all objectAtIndex: i]; c = [NSString stringWithFormat: @"%@=%@", [cc name], [cc value]]; [Cookie setCookie: c]; NSLog([Cookie cookie]) // Prints the cookie fine. } [receivedData setLength:0]; } I can see and print the cookie when I am in the method but I cant when trying to access it form anywhere else even though it gets stored in the holder class @interface Cookie : NSObject { NSString* cookie; } + (NSString*) cookie; + (void) setCookie: (NSString*) cookieValue; @end int main (void) { NSAutoreleasePool * pool = [[NSAutoreleasePool alloc] init]; JCLogin* login; login = [JCLogin new]; [login DoLogin]; NSLog([Cookie cookie]); // Crashes the program [pool drain]; return 0; }

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• Best way to run multiple queries per second on database, performance wise?

  - by Michael Joell

  I am currently using Java to insert and update data multiple times per second. Never having used databases with Java, I am not sure what is required, and how to get the best performance. I currently have a method for each type of query I need to do (for example, update a row in a database). I also have a method to create the database connection. Below is my simplified code. public static void addOneForUserInChannel(String channel, String username) throws SQLException { Connection dbConnection = null; PreparedStatement ps = null; String updateSQL = "UPDATE " + channel + "_count SET messages = messages + 1 WHERE username = ?"; try { dbConnection = getDBConnection(); ps = dbConnection.prepareStatement(updateSQL); ps.setString(1, username); ps.executeUpdate(); } catch(SQLException e) { System.out.println(e.getMessage()); } finally { if(ps != null) { ps.close(); } if(dbConnection != null) { dbConnection.close(); } } } And my DB connection private static Connection getDBConnection() { Connection dbConnection = null; try { Class.forName(DB_DRIVER); } catch (ClassNotFoundException e) { System.out.println(e.getMessage()); } try { dbConnection = DriverManager.getConnection(DB_CONNECTION, DB_USER,DB_PASSWORD); return dbConnection; } catch (SQLException e) { System.out.println(e.getMessage()); } return dbConnection; } This seems to be working fine for now, with about 1-2 queries per second, but I am worried that once I expand and it is running many more, I might have some issues. My questions: Is there a way to have a persistent database connection throughout the entire run time of the process? If so, should I do this? Are there any other optimizations that I should do to help with performance? Thanks

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