Search Results

Search found 13710 results on 549 pages for 'relational model'.

Page 39/549 | < Previous Page | 35 36 37 38 39 40 41 42 43 44 45 46  | Next Page >

  • Which parallel pattern to use?

    - by Wim Van Houts
    I need to write a server application that fetches mails from different mail servers/mailboxes and then needs to process/analyze these mails. Traditionally, I would do this multi-threaded, launching a thread for fetching mails (or maybe one per mailbox) and then process the mails. We are moving more and more to servers where we have 8+ cores, so I would like to make use of these cores as much as possible (and not use 1 at 100% and leave the seven others untouched). So conceptually, as an example, it would be nice that I could write the application in such a way that two cores are "continuously" fetching emails and four cores are "continuously" processing/analyzing the emails (since processing and analyzing mails is more CPU intensive than fetching mails). This seems like a good concept, but after studying some parallel patterns, I'm not really sure how this is best implemented. None of the patterns really fit. I'm working in VS2012, native C++, but I guess from a design point of view this does not really matter and just some pointers on how to organize this would be great!

    Read the article

  • Is Akka a good solution for a concurrent pipeline/workflow problem?

    - by herpylderp
    Disclaimer: I am brand new to Akka and the concept of Actors/Event-Driven Architectures in general. I have to implement a fairly complex problem where users can configure a "concurrent pipeline": Pipeline: consists of 1+ Stages; all Stages execute sequentially Stage: consists of 1+ Tasks; all Tasks execute in parallel Task: essentially a Java Runnable As you can see above, a Task is a Runnable that does some unit of work. Tasks are organized into Stages, which execute their Tasks in parallel. Stages are organized into the Pipeline, which executes its Stages sequentially. Hence if a user specifies the following Pipeline: CrossTheRoadSafelyPipeline Stage 1: Look Left Task 1: Turn your head to the left and look for cars Task 2: Listen for cars Stage 2: Look right Task 1: Turn your head to the right and look for cars Task 2: Listen for cars Then, Stage 1 will execute, and then Stage 2 will execute. However, while each Stage is executing, it's individual Tasks are executing in parallel/at the same time. In reality Pipelines will become very complicated, and with hundreds of Stages, dozens of Tasks per Stage (again, executing at the same time). To implement this Pipeline I can only think of several solutions: ESB/Apache Camel Guava Event Bus Java 5 Concurrency Actors/Akka Camel doesn't seem right because its core competency is integration not synchrony and orchestration across worker threads. Guava is great, but this doesn't really feel like a subscriber/publisher-type of problem. And Java 5 Concurrency (ExecutorService, etc.) just feels too low-level and painful. So I ask: is Akka a strong candidate for this type of problem? If so, how? If not, then why, and what is a good candidate?

    Read the article

  • How best to look up objects by label?

    - by dsollen
    I am writing the server backed by a pre-written API. I'm going to get a number of strings representing ports, signals, paths, etc etc etc. I need to look up the object associated with a given label, these objects are all in memory (no sql magic to do this for me). My question is, how best do I associate a given unique label with the mutable object it represents? I have enough objects that looking through every signal or every port to find the one that matches is possible, but may be slightly too slow. To be honest the direct 'look at every object' method is probably good enough for so small a body of objects and anything else is premature optimization, but I still am curious what the proper solution would be if I thought my signals were going to grow a bit larger. As I see it there are two options available. First would be to to create a 'store' that is a simple map between object and label. I could have it so that every time I call addObject the object is automatically saved into a hashmap or the like. This works, but relies on my properly adding and deleting each object so the map doesn't grow indefinitely. The biggest issue to me is that this involves having some hidden static map in my ModelObject class that just feels...wrong somehow. The other option is to have some method that can interpret the labels. All of these labels are derived from the underlying objects. So I can look at the signal label, for instance, and say "these 20 characters are the port" to figure out what port I need. This would allow me to quickly figure out what I need. However, if the label method is changed the translateLabelToObject method needs to be updated as well or everything breaks. Which solution is cleaner, or possibly a cleaner solution than either of above? For the record I'm working with sufficient number of variables to make direct comparison a little slow, but not enough to be concerned about memory overhead, written in java. All objects that have labels I need to look up extend the same parent class.

    Read the article

  • MVC Can the model know ANYTHING about the view?

    - by AwDogsGo2Heaven
    I'm working on a game, and without getting into any details I am using MVC "patterns", "rules" or whatever you want to call it to make the game. The view includes everything needed to draw things on the screen, the controller passes input to the model. And the Model contains game logic. Here's my problem, the game is being made for mobile devices that vary in screen sizes. I feel my model needs to know the view size so it can appropriately adjust for it. I've thought about it for a while I could put all the adjustments in the view, but it just seems inefficient to translate the model positioning to the view's needed positioning every time. If the model knows the size it only needed to adjust itself once. So my question is can I pass the view size to the model without 'breaking' MVC? I feel personally they are still decoupled this way because a size is just a number, I could still change the view any time as long as it has a size. But I wanted to get a community response on this because I haven't seen many discussions of MVC being used in a game. (And to be clear I don't want an answer of why I shouldn't use it in a game, but do I break MVC by letting it know the view's size) EDIT - More details on the game's needs and why I wanted to pass the view. Some objects positions need to be set relative to the edge of the screen (such as UI elements) so that they appear relatively in the same place. Sprite sizes are not stretched if the window size is wider such as an IPhone 5 screen. They will just be placed relatively to the screen edge. .If I gave it to the view to handle this, I will need a flag saying that this element is positioned say x number of pixels from TOP BOTTOM RIGHT LEFT. Then allow the view to draw it with that information. Its acceptable, I just wanted to know if there was a better way while still being MVC because it seems this way will be repeating a logic over and over, where as if I knew the view size in the model, I could convert all the relative positions into absolute positions in one run, but with this I have to convert on every update to the screen.

    Read the article

  • C#: Inheritence, Overriding, and Hiding

    - by Rosarch
    I'm having difficulty with an architectural decision for my C# XNA game. The basic entity in the world, such as a tree, zombie, or the player, is represented as a GameObject. Each GameObject is composed of at least a GameObjectController, GameObjectModel, and GameObjectView. These three are enough for simple entities, like inanimate trees or rocks. However, as I try to keep the functionality as factored out as possible, the inheritance begins to feel unwieldy. Syntactically, I'm not even sure how best to accomplish my goals. Here is the GameObjectController: public class GameObjectController { protected GameObjectModel model; protected GameObjectView view; public GameObjectController(GameObjectManager gameObjectManager) { this.gameObjectManager = gameObjectManager; model = new GameObjectModel(this); view = new GameObjectView(this); } public GameObjectManager GameObjectManager { get { return gameObjectManager; } } public virtual GameObjectView View { get { return view; } } public virtual GameObjectModel Model { get { return model; } } public virtual void Update(long tick) { } } I want to specify that each subclass of GameObjectController will have accessible at least a GameObjectView and GameObjectModel. If subclasses are fine using those classes, but perhaps are overriding for a more sophisticated Update() method, I don't want them to have to duplicate the code to produce those dependencies. So, the GameObjectController constructor sets those objects up. However, some objects do want to override the model and view. This is where the trouble comes in. Some objects need to fight, so they are CombatantGameObjects: public class CombatantGameObject : GameObjectController { protected new readonly CombatantGameModel model; public new virtual CombatantGameModel Model { get { return model; } } protected readonly CombatEngine combatEngine; public CombatantGameObject(GameObjectManager gameObjectManager, CombatEngine combatEngine) : base(gameObjectManager) { model = new CombatantGameModel(this); this.combatEngine = combatEngine; } public override void Update(long tick) { if (model.Health <= 0) { gameObjectManager.RemoveFromWorld(this); } base.Update(tick); } } Still pretty simple. Is my use of new to hide instance variables correct? Note that I'm assigning CombatantObjectController.model here, even though GameObjectController.Model was already set. And, combatants don't need any special view functionality, so they leave GameObjectController.View alone. Then I get down to the PlayerController, at which a bug is found. public class PlayerController : CombatantGameObject { private readonly IInputReader inputReader; private new readonly PlayerModel model; public new PlayerModel Model { get { return model; } } private float lastInventoryIndexAt; private float lastThrowAt; public PlayerController(GameObjectManager gameObjectManager, IInputReader inputReader, CombatEngine combatEngine) : base(gameObjectManager, combatEngine) { this.inputReader = inputReader; model = new PlayerModel(this); Model.Health = Constants.PLAYER_HEALTH; } public override void Update(long tick) { if (Model.Health <= 0) { gameObjectManager.RemoveFromWorld(this); for (int i = 0; i < 10; i++) { Debug.WriteLine("YOU DEAD SON!!!"); } return; } UpdateFromInput(tick); // .... } } The first time that this line is executed, I get a null reference exception: model.Body.ApplyImpulse(movementImpulse, model.Position); model.Position looks at model.Body, which is null. This is a function that initializes GameObjects before they are deployed into the world: public void Initialize(GameObjectController controller, IDictionary<string, string> data, WorldState worldState) { controller.View.read(data); controller.View.createSpriteAnimations(data, _assets); controller.Model.read(data); SetUpPhysics(controller, worldState, controller.Model.BoundingCircleRadius, Single.Parse(data["x"]), Single.Parse(data["y"]), bool.Parse(data["isBullet"])); } Every object is passed as a GameObjectController. Does that mean that if the object is really a PlayerController, controller.Model will refer to the base's GameObjectModel and not the PlayerController's overriden PlayerObjectModel?

    Read the article

  • OBJ model loaded in LWJGL has a black area with no texture

    - by gambiting
    I have a problem with loading an .obj file in LWJGL and its textures. The object is a tree(it's a paid model from TurboSquid, so I can't post it here,but here's the link if you want to see how it should look like): http://www.turbosquid.com/FullPreview/Index.cfm/ID/701294 I wrote a custom OBJ loader using the LWJGL tutorial from their wiki. It looks like this: public class OBJLoader { public static Model loadModel(File f) throws FileNotFoundException, IOException { BufferedReader reader = new BufferedReader(new FileReader(f)); Model m = new Model(); String line; Texture currentTexture = null; while((line=reader.readLine()) != null) { if(line.startsWith("v ")) { float x = Float.valueOf(line.split(" ")[1]); float y = Float.valueOf(line.split(" ")[2]); float z = Float.valueOf(line.split(" ")[3]); m.verticies.add(new Vector3f(x,y,z)); }else if(line.startsWith("vn ")) { float x = Float.valueOf(line.split(" ")[1]); float y = Float.valueOf(line.split(" ")[2]); float z = Float.valueOf(line.split(" ")[3]); m.normals.add(new Vector3f(x,y,z)); }else if(line.startsWith("vt ")) { float x = Float.valueOf(line.split(" ")[1]); float y = Float.valueOf(line.split(" ")[2]); m.texVerticies.add(new Vector2f(x,y)); }else if(line.startsWith("f ")) { Vector3f vertexIndicies = new Vector3f(Float.valueOf(line.split(" ")[1].split("/")[0]), Float.valueOf(line.split(" ")[2].split("/")[0]), Float.valueOf(line.split(" ")[3].split("/")[0])); Vector3f textureIndicies = new Vector3f(Float.valueOf(line.split(" ")[1].split("/")[1]), Float.valueOf(line.split(" ")[2].split("/")[1]), Float.valueOf(line.split(" ")[3].split("/")[1])); Vector3f normalIndicies = new Vector3f(Float.valueOf(line.split(" ")[1].split("/")[2]), Float.valueOf(line.split(" ")[2].split("/")[2]), Float.valueOf(line.split(" ")[3].split("/")[2])); m.faces.add(new Face(vertexIndicies,textureIndicies,normalIndicies,currentTexture.getTextureID())); }else if(line.startsWith("g ")) { if(line.length()>2) { String name = line.split(" ")[1]; currentTexture = TextureLoader.getTexture("PNG", ResourceLoader.getResourceAsStream("res/" + name + ".png")); System.out.println(currentTexture.getTextureID()); } } } reader.close(); System.out.println(m.verticies.size() + " verticies"); System.out.println(m.normals.size() + " normals"); System.out.println(m.texVerticies.size() + " texture coordinates"); System.out.println(m.faces.size() + " faces"); return m; } } Then I create a display list for my model using this code: objectDisplayList = GL11.glGenLists(1); GL11.glNewList(objectDisplayList, GL11.GL_COMPILE); Model m = null; try { m = OBJLoader.loadModel(new File("res/untitled4.obj")); } catch (Exception e1) { e1.printStackTrace(); } int currentTexture=0; for(Face face: m.faces) { if(face.texture!=currentTexture) { currentTexture = face.texture; GL11.glBindTexture(GL11.GL_TEXTURE_2D, currentTexture); } GL11.glColor3f(1f, 1f, 1f); GL11.glBegin(GL11.GL_TRIANGLES); Vector3f n1 = m.normals.get((int) face.normal.x - 1); GL11.glNormal3f(n1.x, n1.y, n1.z); Vector2f t1 = m.texVerticies.get((int) face.textures.x -1); GL11.glTexCoord2f(t1.x, t1.y); Vector3f v1 = m.verticies.get((int) face.vertex.x - 1); GL11.glVertex3f(v1.x, v1.y, v1.z); Vector3f n2 = m.normals.get((int) face.normal.y - 1); GL11.glNormal3f(n2.x, n2.y, n2.z); Vector2f t2 = m.texVerticies.get((int) face.textures.y -1); GL11.glTexCoord2f(t2.x, t2.y); Vector3f v2 = m.verticies.get((int) face.vertex.y - 1); GL11.glVertex3f(v2.x, v2.y, v2.z); Vector3f n3 = m.normals.get((int) face.normal.z - 1); GL11.glNormal3f(n3.x, n3.y, n3.z); Vector2f t3 = m.texVerticies.get((int) face.textures.z -1); GL11.glTexCoord2f(t3.x, t3.y); Vector3f v3 = m.verticies.get((int) face.vertex.z - 1); GL11.glVertex3f(v3.x, v3.y, v3.z); GL11.glEnd(); } GL11.glEndList(); The currentTexture is an int - it contains the ID of the currently used texture. So my model looks absolutely fine without textures: (sorry I cannot post hyperlinks since I am a new user) i.imgur.com/VtoK0.png But look what happens if I enable GL_TEXTURE_2D: i.imgur.com/z8Kli.png i.imgur.com/5e9nn.png i.imgur.com/FAHM9.png As you can see an entire side of the tree appears to be missing - and it's not transparent, since it's not in the colour of the background - it's rendered black. It's not a problem with the model - if I load it using Kanji's OBJ loader it works fine(but the thing is,that I need to write my own OBJ loader) i.imgur.com/YDATo.png this is my OpenGL init section: //init display try { Display.setDisplayMode(new DisplayMode(Support.SCREEN_WIDTH, Support.SCREEN_HEIGHT)); Display.create(); Display.setVSyncEnabled(true); } catch (LWJGLException e) { e.printStackTrace(); System.exit(0); } GL11.glLoadIdentity(); GL11.glEnable(GL11.GL_TEXTURE_2D); GL11.glClearColor(1.0f, 0.0f, 0.0f, 1.0f); GL11.glShadeModel(GL11.GL_SMOOTH); GL11.glEnable(GL11.GL_DEPTH_TEST); GL11.glDepthFunc(GL11.GL_LESS); GL11.glDepthMask(true); GL11.glEnable(GL11.GL_NORMALIZE); GL11.glMatrixMode(GL11.GL_PROJECTION); GLU.gluPerspective (90.0f,800f/600f, 1f, 500.0f); GL11.glMatrixMode(GL11.GL_MODELVIEW); GL11.glEnable(GL11.GL_CULL_FACE); GL11.glCullFace(GL11.GL_BACK); //enable lighting GL11.glEnable(GL11.GL_LIGHTING); ByteBuffer temp = ByteBuffer.allocateDirect(16); temp.order(ByteOrder.nativeOrder()); GL11.glMaterial(GL11.GL_FRONT, GL11.GL_DIFFUSE, (FloatBuffer)temp.asFloatBuffer().put(lightDiffuse).flip()); GL11.glMaterialf(GL11.GL_FRONT, GL11.GL_SHININESS,(int)material_shinyness); GL11.glLight(GL11.GL_LIGHT2, GL11.GL_DIFFUSE, (FloatBuffer)temp.asFloatBuffer().put(lightDiffuse2).flip()); // Setup The Diffuse Light GL11.glLight(GL11.GL_LIGHT2, GL11.GL_POSITION,(FloatBuffer)temp.asFloatBuffer().put(lightPosition2).flip()); GL11.glLight(GL11.GL_LIGHT2, GL11.GL_AMBIENT,(FloatBuffer)temp.asFloatBuffer().put(lightAmbient).flip()); GL11.glLight(GL11.GL_LIGHT2, GL11.GL_SPECULAR,(FloatBuffer)temp.asFloatBuffer().put(lightDiffuse2).flip()); GL11.glLightf(GL11.GL_LIGHT2, GL11.GL_CONSTANT_ATTENUATION, 0.1f); GL11.glLightf(GL11.GL_LIGHT2, GL11.GL_LINEAR_ATTENUATION, 0.0f); GL11.glLightf(GL11.GL_LIGHT2, GL11.GL_QUADRATIC_ATTENUATION, 0.0f); GL11.glEnable(GL11.GL_LIGHT2); Could somebody please help me?

    Read the article

  • The Next-gen Databases

    - by Randin
    I'm learning traditional Relational Databases (with PostgreSQL) and doing some research I've come across some new types of databases. CouchDB, Drizzle, and Scalaris to name a few, what is going to be the next database technologies to deal with?

    Read the article

  • Database design -- does it respect 3rd NF?

    - by Flavius
    Hi I have the following relations (tables) in a relational model Person person_id, first_name, last_name, address Student person_id, matr_nr Teacher person_id, salary Lecture lecture_id, lect_name, lect_description Attendees lecture_id, person_id, date I'm wondering about the functional dependencies of Student and Teacher. Do these tables respect the 3rd normal form? Which should be the primary keys of these tables?

    Read the article

  • Sharing the model in MVP Winforms App

    - by Keith G
    I'm working on building up an MVP application (C# Winforms). My initial version is at http://stackoverflow.com/questions/1422343/ ... Now I'm increasing the complexity. I've broken out the code to handle two separate text fields into two view/presenter pairs. It's a trivial example, but it's to work out the details of multiple presenters sharing the same model. My questions are about the model: I am basically using a property changed event raised by the model for notifying views that something has changed. Is that a good approach? What if it gets to the point where I have 100 or 1000 properties? Is it still practical at that point? Is instantiating the model in each presenter with   NoteModel _model = NoteModel.Instance   the correct approach? Note that I do want to make sure all of the presenters are sharing the same data. If there is a better approach, I'm open to suggestions .... My code looks like this: NoteModel.cs public class NoteModel : INotifyPropertyChanged { private static NoteModel _instance = null; public static NoteModel Instance { get { return _instance; } } static NoteModel() { _instance = new NoteModel(); } private NoteModel() { Initialize(); } public string Filename { get; set; } public bool IsDirty { get; set; } public readonly string DefaultName = "Untitled.txt"; string _sText; public string TheText { get { return _sText; } set { _sText = value; PropertyHasChanged("TheText"); } } string _sMoreText; public string MoreText { get { return _sMoreText; } set { _sMoreText = value; PropertyHasChanged("MoreText"); } } public void Initialize() { Filename = DefaultName; TheText = String.Empty; MoreText = String.Empty; IsDirty = false; } private void PropertyHasChanged(string sPropName) { IsDirty = true; if (PropertyChanged != null) { PropertyChanged(this, new PropertyChangedEventArgs(sPropName)); } } public event PropertyChangedEventHandler PropertyChanged; } TextEditorPresenter.cs public class TextEditorPresenter { ITextEditorView _view; NoteModel _model = NoteModel.Instance; public TextEditorPresenter(ITextEditorView view)//, NoteModel model) { //_model = model; _view = view; _model.PropertyChanged += new PropertyChangedEventHandler(model_PropertyChanged); } void model_PropertyChanged(object sender, PropertyChangedEventArgs e) { if (e.PropertyName == "TheText") _view.TheText = _model.TheText; } public void TextModified() { _model.TheText = _view.TheText; } public void ClearView() { _view.TheText = String.Empty; } } TextEditor2Presenter.cs is essentially the same except it operates on _model.MoreText instead of _model.TheText. ITextEditorView.cs public interface ITextEditorView { string TheText { get; set; } } ITextEditor2View.cs public interface ITextEditor2View { string MoreText { get; set; } }

    Read the article

  • Need help with NHibernate / Fluent NHibernate mapping

    - by Mark Boltuc
    Let's say your have the following table structure: ============================== | Case | ============================== | Id | int | | ReferralType | varchar(10) | +---------| ReferralId | int |---------+ | ============================== | | | | | | | ====================== ====================== ====================== | SourceA | | SourceB | | SourceC | ====================== ====================== ====================== | Id | int | | Id | int | | Id | int | | Name | varchar(50) | | Name | varchar(50) | | Name | varchar(50) | ====================== ====================== ====================== Based on the ReferralType the ReferralId contains id to the SourceA, SourceB, or SourceC I'm trying to figure out how to map this using Fluent NHibernate or just plain NHibernate into an object model. I've tried a bunch of different things but I haven't been succesful. Any ideas? The object model might be something like: public class Case { public int Id { get; set; } public Referral { get; set; } } public class Referral { public string Type { get; set; } public int Id { get; set; } public string Name { get; set; } }

    Read the article

  • Is there a way to update a ViewModel in MVC2?

    - by Juvaly
    This code works: [HttpPost] public ActionResult Edit(int id, FormCollection fc) { Movie movie = ( from m in _ctx.Movie.Include("MovieActors") where m.MovieID == id select m ).First(); MovieActorViewModel movieActor = new MovieActorViewModel(movie); if (TryUpdateModel(movieActor)) { _ctx.ApplyPropertyChanges(movieActor.Movie.EntityKey.EntitySetName, movieActor.Movie); _ctx.SaveChanges(); } return View(movieActor); } However, I am not sure how to test this, and in general would much rather have the method take a typed model like: [HttpPost] public ActionResult Edit(MovieActorViewModel movieActor) Is this possible? What changes to my MovieActorViewModel class do I need to make in order to enable this? That class looks like this: public class MovieActorViewModel { public Movie Movie { get; set; } public Actor Actor { get; set; } public PublisherDealViewModel(Movie movie) { this.Movie = movie; this.Actor = ( from a in this.Movie.Actors where a.ActorID == 1 select a ).First(); } } The view is typed (inherits ViewPage) simple: <% using (Html.BeginForm()) {%> Movie Title: <%= Html.TextBoxFor(model=>model.Movie.Title) %><br/> Actor Name: <%= Html.TextBoxFor(model=>model.Actor.Name) %> <% } %>

    Read the article

  • PS/2 to USB adapter doesn't work with Model M keyboard

    - by mickburkejnr
    I bought a server about 3 months ago from a friend, and I have only had time to tinker with it in the last week. I noticed that this server doesn't have any PS/2 ports, which meant configuring it was near impossible. I don't have any USB keyboards in the house, I only have an IBM Model M keyboard (built 1994) and another IBM keyboard that was built circa 2001. Both of them have PS/2 connections. I bought an adapter off eBay, and when I used it with the Model M keyboard the three lights on the keyboard flashed for a split second, but then the keyboard is then unresponsive. I can bash away at the keys for ages and nothing will happen. The same applies to the later built IBM keyboard. What could I do to make the adapter work? I am getting the loan of a USB keyboard in two weeks time, but I'd like a more permanent solution without having to rely on getting the loan of a keyboard every time I have to perform maintenance on the server. And as I already have two keyboards which work fine and I like using, I don't really want to have to buy another keyboard just for use on the server.

    Read the article

  • How to map IEnumerable<SelectListItem> to IList<> for ListBox

    - by Superhuman
    I have two classes. Class1 and Class2. public class Class1{ ... public virtual IList<Class2> Class2s{get;set;} ... } public class Class2{ ... public virtual IList<Class1> Class1s{get;set;} ... } The view contains <%=Html.ListBox("Class2s", ViewData.Model.Class2s.Select( x => new SelectListItem { Text = x.Name, Value = x.Id.ToString(), Selected = ViewData.Model.Class1.Class2s.Any(y => y.Id == x.Id) }) They have many to many mapping. I have a ListBox in Class1 view which displays Class2. How to map the output of the ListBox back to IList Class2s property of Class1? I am able to display the values in the ListBox but unable to map back the SelectListItem to IList.

    Read the article

  • access exception when invoking method of an anonymous class using java reflection

    - by Asaf David
    Hello I'm trying to use an event dispatcher to allow a model to notify subscribed listeners when it changes. the event dispatcher receives a handler class and a method name to call during dispatch. the presenter subscribes to the model changes and provide a Handler implementation to be called on changes. Here's the code (I'm sorry it's a bit long). EventDispacther: package utils; public class EventDispatcher<T> { List<T> listeners; private String methodName; public EventDispatcher(String methodName) { listeners = new ArrayList<T>(); this.methodName = methodName; } public void add(T listener) { listeners.add(listener); } public void dispatch() { for (T listener : listeners) { try { Method method = listener.getClass().getMethod(methodName); method.invoke(listener); } catch (Exception e) { System.out.println(e.getMessage()); } } } } Model: package model; public class Model { private EventDispatcher<ModelChangedHandler> dispatcher; public Model() { dispatcher = new EventDispatcher<ModelChangedHandler>("modelChanged"); } public void whenModelChange(ModelChangedHandler handler) { dispatcher.add(handler); } public void change() { dispatcher.dispatch(); } } ModelChangedHandler: package model; public interface ModelChangedHandler { void modelChanged(); } Presenter: package presenter; public class Presenter { private final Model model; public Presenter(Model model) { this.model = model; this.model.whenModelChange(new ModelChangedHandler() { @Override public void modelChanged() { System.out.println("model changed"); } }); } } Main: package main; public class Main { public static void main(String[] args) { Model model = new Model(); Presenter presenter = new Presenter(model); model.change(); } } Now, I except to get the "model changed" message. However, I'm getting an java.lang.IllegalAccessException: Class utils.EventDispatcher can not access a member of class presenter.Presenter$1 with modifiers "public". I understand that the class to blame is the anonymous class i created inside the presenter, however I don't know how to make it any more 'public' than it currently is. If i replace it with a named nested class it seem to work. It also works if the Presenter and the EventDispatcher are in the same package, but I can't allow that (several presenters in different packages should use the EventDispatcher) any ideas?

    Read the article

  • Cakephp Insert Ignore Feature?

    - by SeanDowney
    Is there a way to do an "insert ignore" in cake without using a model-query function? $this->Model->save(array( 'id' => NULL, 'guid' => $guid, 'name' => $name, )); Generates error: Warning (512): SQL Error: 1062: Duplicate entry 'GUID.....' for key 'unique_guid' [CORE/cake/libs/model/datasources/dbo_source.php, line 524] It would be great to be able to set some flag or option that says "don't care"

    Read the article

  • Limit a user to view only associated records in rails

    - by trobrock
    I have an application with three Models (Profile - SubModel - SubSubModel) chained together with has many relationships. I am trying to limit a user, after logging in, to only retrieving records that are associated with their Profile. I am very new to rails and this is what I had been trying in the Profile model has_many :submodels, :conditions => {:profile_id => self.id} but this is returning an empty data set when calling with Profile.find_by_id(1).submodels, how else could I achieve what I am trying to do. Or should I handle this in the controller or view instead, I thought it sounded well suited for the model to handle this.

    Read the article

  • Model-View-Controller in JavaScript

    - by Casey Hope
    tl;dr: How does one implement MVC in JavaScript in a clean way? I'm trying to implement MVC in JavaScript. I have googled and reorganized with my code countless times but have not found a suitable solution. (The code just doesn't "feel right".) Here's how I'm going about it right now. It's incredibly complicated and is a pain to work with (but still better than the pile of code I had before). It has ugly workarounds that sort of defeat the purpose of MVC. And behold, the mess, if you're really brave: // Create a "main model" var main = Model0(); function Model0() { // Create an associated view and store its methods in "view" var view = View0(); // Create a submodel and pass it a function // that will "subviewify" the submodel's view var model1 = Model1(function (subview) { view.subviewify(subview); }); // Return model methods that can be used by // the controller (the onchange handlers) return { 'updateModel1': function (newValue) { model1.update(newValue); } }; } function Model1(makeSubView) { var info = ''; // Make an associated view and attach the view // to the parent view using the passed function var view = View1(); makeSubView(view.__view); // Dirty dirty // Return model methods that can be used by // the parent model (and so the controller) return { 'update': function (newValue) { info = newValue; // Notify the view of the new information view.events.value(info); } }; } function View0() { var thing = document.getElementById('theDiv'); var input = document.getElementById('theInput'); // This is the "controller", bear with me input.onchange = function () { // Ugly, uses a global to contact the model main.updateModel1(this.value); }; return { 'events': {}, // Adds a subview to this view. 'subviewify': function (subview) { thing.appendChild(subview); } }; } // This is a subview. function View1() { var element = document.createElement('div'); return { 'events': { // When the value changes this is // called so the view can be updated 'value': function (newValue) { element.innerHTML = newValue; } }, // ..Expose the DOM representation of the subview // so it can be attached to a parent view '__view': element }; } How does one implement MVC in JavaScript in a cleaner way? How can I improve this system? Or is this the completely wrong way to go, should I follow another pattern?

    Read the article

  • SOA design principles with regards to database relationships

    - by Eitan
    If I were to extricate my current membership provider from my solution, i.e. as a dll and expose it as a web service with it's own db, how would I model the relationships with regards to SOA design. For example I have a table: USER id, name, lastname, username, password, role. and table PRODUCT id, name, price, createdate, userid the foreign key being userid to table user. How would I model the relationship and/or query the db. If I wanted to get all products that were uploaded today for example, before I would query: SELECT u.name, u.lastname, u.username, p.* FROM PRODUCT p INNER JOIN USER u ON p.userid = u.id WHERE createdate = '05/05/2010' Now that I don't have the table within the database how would I perform this query? Thanks.

    Read the article

  • Binding, Prefixes and generated HTML

    - by Vman
    MVC newbie question re binders. Supposing I have two strongly typed partial actions that happen to have a model attributes with the same name, and are rendered in the same containing page i.e.: Class Friend {string Name {get; set ;} DateTime DOB {get; set ;}} Class Foe {string Name {get; set ;} string ReasonForDislike {get; set ;}} Both partials will have a line: <%= Html.TextBoxFor(model => model.Name) %> And associated controller actions: public ActionResult SaveFriend(Friend friend) public ActionResult SaveFoe(Foe foe) My problem is that both will render on my containing page with the same id (of course, bad for lots of reasons). I’m aware of the [Bind] attribute that allows me add a prefix, resulting in code: public ActionResult SaveFriend([Bind(Prefix = “friend”)] Friend friend) <%= Html.TextBox("friend.Name", Model. Name) %> //Boo, no TextBoxFor :( But this still doesn’t cut it. I can just about tolerate the loss of the strongly typed TextBoxFor helpers but I’ve yet to get clientside validation to work with prefixes: I’ve tried: <%= Html.ValidationMessage("friend.Name") %> ...and every other variant I can think of. I seem to need the model to be aware of the prefix in both directions but bind only applies when mapping the inbound request. It seems (to me) a common scenario but I’m struggling to find examples out there. What am I missing! Thanks in advance.

    Read the article

  • asp .net MVC 2.0 Validation

    - by ANDyW
    Hi I’m trying to do some validation in asp .net MVC 2.0 for my application. I want to have some nice client side validation. Validation should be done most time on model side with DataAnnotations with custom attributes( like CompareTo, StringLenght, MinPasswordLenght (from Membership.MinimumumpassworkdLenght value). For that purpose I tried to use xval with jquery.validation. Some specific thing is that most of forms will be working with ajax and most problems are when I want to validate form with ajax. Here is link for sample project http://www.sendspace.com/file/m9gl54 . I got two forms as controls ValidFormControl1.ascx, ValidFormControl2.ascx <% using (Ajax.BeginForm("CreateValidForm", "Test", new AjaxOptions { HttpMethod = "Post" })) {%> <div id="validationSummary1"> <%= Html.ValidationSummary(true)%> </div> <fieldset> <legend>Fields</legend> <div class="editor-label"> <%= Html.LabelFor(model => model.Name)%> </div> <div class="editor-field"> <%= Html.TextBoxFor(model => model.Name)%> <%= Html.ValidationMessageFor(model => model.Name)%> </div> <div class="editor-label"> <%= Html.LabelFor(model => model.Email)%> </div> <div class="editor-field"> <%= Html.TextBoxFor(model => model.Email)%> <%= Html.ValidationMessageFor(model => model.Email)%> </div> <div class="editor-label"> <%= Html.LabelFor(model => model.Password)%> </div> <div class="editor-field"> <%= Html.TextBoxFor(model => model.Password)%> <%= Html.ValidationMessageFor(model => model.Password)%> </div> <div class="editor-label"> <%= Html.LabelFor(model => model.ConfirmPassword)%> </div> <div class="editor-field"> <%= Html.TextBoxFor(model => model.ConfirmPassword)%> <%= Html.ValidationMessageFor(model => model.ConfirmPassword)%> </div> <p> <input type="submit" value="Create" /> </p> </fieldset> <% } %> <%= Html.ClientSideValidation<ValidModel>() .UseValidationSummary("validationSummary1", "Please fix the following problems:") %> Both look same the difference is only validation summaryID (validationSummary1, validationSummary2). Both controls are rendered on one page : Form2 <%Html.RenderPartial("~/Views/Test/ValidFormControl2.ascx", null); %> Form1 <%Html.RenderPartial("~/Views/Test/ValidFormControl.ascx", null); %> Validation property First problem, when we have two controls with same type to validate it don’t work becosue html elements are rendered by field name ( so we have two element with same name “Password” ). Only first form will be validated by client side. The worst thing is that even if we have different types and their fields name is same validation won’t work too ( this thing is what I need to repair it will be stupid to name some unique properites for validation ). Is there any solution for this ? Custom attributes validation Next thing custom attributes validation ( All those error are when I use Ajax for on normal form validation is working without problem. ): CompareTo - Simple compare to that is done in mvc template for account model ( class attribute saying with two property will be compared ) , and it wasn’t show on page. To do it I created own CachingRulesProvider with compareRule and my Attribute. Maybe there is more easy way to do it? StringLenght with minimum and maximum value, I won’t describe how I done it but is there any easy whey to do it? Validation summary When I have two two control on page all summary validation information goes to first control validation summary element, even xval generated script say that elementID are different for summary. Any one know how to repair it? Validation Information Is there any option to turn on messages on place where is Html.ValidationMessageFor(model = model.ConfirmPassword). Becsoue for me it isn’t show up. I would like to have summary and near field information too not only red border. Any one know how to do it? Ajax submit Anyone know how to do easy without massive code in javascript to do submit via javascript. This will be used to change input submit to href element (a). Both look same the difference is only validation summaryID

    Read the article

  • ASP.NET MVC CRUD PartialView Popup Issue

    - by Smiley Face
    I am creating an MVC website which makes use of Partial Views on Popups to handle all my CRUD transactions. Please note that my application can already handle these CRUD operations perfectly (LINQ-To-Entity). However, I have a problem with my popup forms. Below is the code from my _Add.cshtml: @model MyStore.Models.MyModels.ProductsModel @{ Layout = null; } @using (Ajax.BeginForm("_Add", "Products", new AjaxOptions { InsertionMode = InsertionMode.Replace, HttpMethod = "POST", OnSuccess = "addSuccess" }, new { @id = "addForm" })) { @Html.ValidationSummary(true) <div id="add-message" class="error invisible"></div> <fieldset> <legend>Products</legend> @Html.HiddenFor(m => Model.ProductCode) <div class="editor-label"> @Html.LabelFor(model => model.ProductName) </div> <div class="editor-field"> @Html.EditorFor(model => model.ProductName) @Html.ValidationMessageFor(model => model.ProductName) </div> <div class="editor-label"> @Html.LabelFor(model => model.Price) </div> <div class="editor-field"> @Html.TextBoxFor(model => model.Price) @Html.ValidationMessageFor(model => model.Price) </div> </fieldset> } Below is the code from my Controller: [HttpGet] public ActionResult _Add(string productCode) { ProductsModel model = newProductsModel(); model.ProductCode = ProductCode ; return PartialView(model); } [HttpPost] public JsonResult _Add(ProductsModel model) { if (ModelState.IsValid) { ProductsManager prod = new ProductsManager(); Products pa = new Products(); pa.ProductCode = model.ProductCode; pa.ProductName = model.ProductName; pa.Price = model.Price; prod.AddProduct(pa); return Json(HelperClass.SuccessResponse(pa), JsonRequestBehavior.AllowGet); } else { return Json(HelperClass.ErrorResponse("Please review your form"), JsonRequestBehavior.DenyGet); } } Please note that the _Add.cshtml is a partial view which is being rendered through a Popup.js which I found on the internet. It is rendered through this code: @Html.ActionLink("[Add Product]", "_Add", new { ProductCode = @ViewData["ProductCode"] }, new { @class = "editLink" }) This works okay. I mean it adds product to my database. But my problem is upon clicking the Proceed button, I get this pop-up download dialog from the page: Can somebody please help me with this? I have a hunch it's because of the HttpMethod i'm using (POST, PUT, GET, DELETE) but i'm not really sure which one is right to use or if it really is the problem in the first place. Any help would be greatly appreciated! PS. Sorry for the long post.

    Read the article

  • Migrating from a single entity to an abstract parent entity with child entities, NSEntityMigrationPolicy not called.

    - by Jimmy Selgen Nielsen
    Hi. I'm trying to upgrade my current application to use an abstract parent entity, with specialized sub entities. I've created a custom NSEntityMigrationPolicy, and in the mapping model I've set the Custom Policy to the name of my class. I'm initializing my persistent store like this, which should be fairly standard : NSError *error=nil; persistentStoreCoordinator = [[NSPersistentStoreCoordinator alloc] initWithManagedObjectModel: [self managedObjectModel]]; NSDictionary *options = [NSDictionary dictionaryWithObjectsAndKeys: [NSNumber numberWithBool:YES], NSMigratePersistentStoresAutomaticallyOption, nil]; if (![persistentStoreCoordinator addPersistentStoreWithType:NSSQLiteStoreType configuration:nil URL:storeUrl options:options error:&error]) { NSLog(@"Error adding persistent store : %@",[error description]); NSAssert(error==nil,[error localizedDescription]); } When i run the app i get the following error : Terminating app due to uncaught exception 'NSInternalInconsistencyException', reason: 'The operation couldn’t be completed. (Cocoa error 134140.)' [error userInfo] contains "reason=Can't find mapping model for migration" I've verified that version 1 of the data model will open, and if i set NSInferMappingModelAutomaticallyOption i get a migration, although my entities are not migrated correctly (as expected). I've verified that the mapping model (cdm) is in the application bundle, but somehow it refuses to find it. I've also set breakpoints and NSLog() statements in the custom migration policy, and none of it runs, with or without NSInferMappingModelAutomaticallyOption Any hints as to why it seems unable to find the mapping model ?

    Read the article

  • why does backbone not send the delete?

    - by Nippysaurus
    I have a very basic backbone (sample) application which just creates and destroys model items. When the model is created the object is persisted with a POST to the web server, but when the model is destroyed there is no DELETE sent to the server? Any idea why this might be? very basic model: window.User = Backbone.Model.extend({ urlRoot: 'users' }); my test code just to create and delete the model: var model = null; $(".add").click(function(){ if (model == null) { model = new window.User; model.set({name: 'meeee'}); model.save(); } }); $(".remove").click(function(){ if (model != null) { model.destroy(); } }); The JSON response when creating the model seems good too:

    Read the article

  • Cnoverting application to MVC architecture

    - by terence6
    I'm practicing writing MVC applications. I have a Mastermind game, that I would like to rewrite as MVC app. I have divided my code to parts, but instead of working game I'm getting empty Frame and an error in "public void paint( Graphics g )". Error comes from calling this method in my view with null argument. But how to overcome this ? MVC was quite simple with swing but awt and it's paint methods are much more complicated. Code of working app : http://paste.pocoo.org/show/224982/ App divided to MVC : Main : public class Main { public static void main(String[] args){ Model model = new Model(); View view = new View("Mastermind", 400, 590, model); Controller controller = new Controller(model, view); view.setVisible(true); } } Controller : import java.awt.*; import java.awt.event.*; public class Controller implements MouseListener, ActionListener { private Model model; private View view; public Controller(Model m, View v){ model = m; view = v; view.addWindowListener( new WindowAdapter(){ public void windowClosing(WindowEvent e){ System.exit(0); } }); view.addMouseListener(this); } public void actionPerformed( ActionEvent e ) { if(e.getSource() == view.checkAnswer){ if(model.isRowFull){ model.check(); } } } public void mousePressed(MouseEvent e) { Point mouse = new Point(); mouse = e.getPoint(); if (model.isPlaying){ if (mouse.x > 350) { int button = 1 + (int)((mouse.y - 32) / 50); if ((button >= 1) && (button <= 5)){ model.fillHole(button); } } } } public void mouseClicked(MouseEvent e) {} public void mouseReleased(MouseEvent e){} public void mouseEntered(MouseEvent e) {} public void mouseExited(MouseEvent e) {} } View : import java.awt.*; import javax.swing.*; import java.awt.event.*; public class View extends Frame implements ActionListener { Model model; JButton checkAnswer; private JPanel button; static final int HIT_X[] = {270,290,310,290,310}, HIT_Y[] = {506,496,496,516,516}; public View(String name, int w, int h, Model m){ model = m; setTitle( name ); setSize( w,h ); setResizable( false ); this.setLayout(new BorderLayout()); button = new JPanel(); button.setSize( new Dimension(400, 100)); button.setVisible(true); checkAnswer = new JButton("Check"); checkAnswer.addActionListener(this); checkAnswer.setSize( new Dimension(200, 30)); button.add( checkAnswer ); this.add( button, BorderLayout.SOUTH); button.setVisible(true); for ( int i=0; i < model.SCORE; i++ ){ for ( int j = 0; j < model.LINE; j++ ){ model.pins[i][j] = new Pin(20,0); model.pins[i][j].setPosition(j*50+30,510-i*50); model.pins[i+model.SCORE][j] = new Pin(8,0); model.pins[i+model.SCORE][j].setPosition(HIT_X[j],HIT_Y[j]-i*50); } } for ( int i=0; i < model.LINE; i++ ){ model.pins[model.OPTIONS][i] = new Pin( 20, i+2 ); model.pins[model.OPTIONS][i].setPosition( 370,i * 50 + 56); } model.combination(); model.paint(null); } public void actionPerformed( ActionEvent e ) { } } Model: import java.awt.*; public class Model extends Frame{ static final int LINE = 5, SCORE = 10, OPTIONS = 20; Pin pins[][] = new Pin[21][LINE]; int combination[] = new int[LINE]; int curPin = 0; int turn = 1; int repaintPin; boolean isUpdate = true, isPlaying = true, isRowFull = false; public Model(){ } void fillHole(int color) { pins[turn-1][curPin].setColor(color+1); repaintPins( turn ); curPin = (curPin+1) % LINE; if (curPin == 0){ isRowFull = true; } } public void paint( Graphics g ) { g.setColor( new Color(238, 238, 238)); g.fillRect( 0,0,400,590); for ( int i=0; i < pins.length; i++ ) { pins[i][0].paint(g); pins[i][1].paint(g); pins[i][2].paint(g); pins[i][3].paint(g); pins[i][4].paint(g); } } public void update( Graphics g ) { if ( isUpdate ) { paint(g); } else { isUpdate = true; pins[repaintPin-1][0].paint(g); pins[repaintPin-1][1].paint(g); pins[repaintPin-1][2].paint(g); pins[repaintPin-1][3].paint(g); pins[repaintPin-1][4].paint(g); } } void repaintPins( int pin ) { repaintPin = pin; isUpdate = false; repaint(); } void check() { int junkPegs[] = new int[LINE], junkCode[] = new int[LINE]; int pegCount = 0, pico = 0; for ( int i = 0; i < LINE; i++ ) { junkPegs[i] = pins[turn-1][i].getColor(); junkCode[i] = combination[i]; } for ( int i = 0; i < LINE; i++ ){ if (junkPegs[i]==junkCode[i]) { pins[turn+SCORE][pegCount].setColor(1); pegCount++; pico++; junkPegs[i] = 98; junkCode[i] = 99; } } for ( int i = 0; i < LINE; i++ ){ for ( int j = 0; j < LINE; j++ ) if (junkPegs[i]==junkCode[j]) { pins[turn+SCORE][pegCount].setColor(2); pegCount++; junkPegs[i] = 98; junkCode[j] = 99; j = LINE; } } repaintPins( turn+SCORE ); if ( pico == LINE ){ isPlaying = false; } else if ( turn >= 10 ){ isPlaying = false; } else{ curPin = 0; isRowFull = false; turn++; } } void combination() { for ( int i = 0; i < LINE; i++ ){ combination[i] = 1 + (int)(Math.random()*5); System.out.print(i+","); } } } class Pin{ private int color, X, Y, radius; private static final Color COLORS[] = { Color.black, Color.white, Color.red, Color.yellow, Color.green, Color.blue, new Color(7, 254, 250)}; public Pin(){ X = 0; Y = 0; radius = 0; color = 0; } public Pin( int r,int c ){ X = 0; Y = 0; radius = r; color = c; } public void paint( Graphics g ){ int x = X-radius; int y = Y-radius; if (color > 0){ g.setColor( COLORS[color]); g.fillOval( x,y,2*radius,2*radius ); } else{ g.setColor( new Color(238, 238, 238) ); g.drawOval( x,y,2*radius-1,2*radius-1 ); } g.setColor( Color.black ); g.drawOval( x,y,2*radius,2*radius ); } public void setPosition( int x,int y ){ this.X = x ; this.Y = y ; } public void setColor( int c ){ color = c; } public int getColor() { return color; } } Any clues on how to overcome this would be great. Have I divided my code improperly ?

    Read the article

< Previous Page | 35 36 37 38 39 40 41 42 43 44 45 46  | Next Page >