Search Results

Search found 13716 results on 549 pages for 'proxy classes'.

Page 471/549 | < Previous Page | 467 468 469 470 471 472 473 474 475 476 477 478  | Next Page >

• Creating a complex tree model in Qt

  - by Zeke

  I'm writing an IRC Client (yes another one). Long story short. I'm writing a Server dialogue that keeps a list of this: Identity Networks Channels Addresses I have 3 different list views that will be for the Networks, Channels and Addresses. When the user changes the Identity (combo box). The network listview will lookup all the networks for that specific Identity. After it loads up the Networks it will automatically select the first network and then load all the channels and addresses for that specific network. The problem is I want to have 3 views for 1 model, to minimise all the memory and the loading of data. So that it makes it much easier to manage and not do a bunch of work. If you'd look at QColumnView it's the same exact thing. But I don't need it to be on one exact page since the views are on entirely different tabs to make it easier to go through the Server dialogue. I'm wondering what will be the best way to go about handling this complexity. The information is stored in a SQLite database. I already have the classes written to extract and store it. Just the modelling is the painful part of this solution.

  Read the article

• Is dependency injection only for service type objects and singletons? (and NOT for gui?)

  - by sensui

  I'm currently experimenting with the Google's guice inversion of control container. I previously had singletons for just about any service (database, active directory) my application used. Now I refactored the code: all the dependencies are given as parameters to constructors. So far, so good. Now the hardest part is with the graphical user interface. I face this problem: I have a table (JTable) of products wrapped in an ProductFrame. I give the dependencies as parameters (EditProductDialog). @Inject public ProductFrame(EditProductDialog editProductDialog) { // ... } // ... @Inject public EditProductDialog(DBProductController productController, Product product) { // ... } The problem is that guice can't know what Product I have selected in the table, so it can't know what to inject in the EditProductDialog. Dependency Injection is pretty viral (if I modify one class to use dependency injection I also need to modify all the other classes it interacts with) so my question is should I directly instantiate EditProductDialog? But then I would have to pass manually the DBProductController to the EditProductDialog and I will also need to pass it to the ProductFrame and all this boils down to not using dependency injection at all. Or is my design flawed and because of that I can't really adapt the project to dependecy injection? Give me some examples of how you used dependency injection with the graphical user interface. All the examples found on the Internet are really simple examples where you use some services (mostly databases) with dependency injection.

  Read the article

• When are predicates appropriate and what is the best pattern for usage

  - by Maxim Gershkovich

  When are predicates appropriate and what is the best pattern for usage? What are the advantages of predicates? It seems to me like most cases where a predicate can be employed a tight loop would accomplish the same functionality? I don’t see a reusability argument given you will probably only implement a predicate in one method right? They look and feel nice but besides that they seem like you would only employ them when you need a quick hack on the collection classes? UPDATE But why would you be rewriting the tight loop again and again? In my mind/code when it comes to collections I always end up with something like Class Person End Class Class PersonList Inherits List(Of Person) Function FindByName(Name) as Person tight loop.... End Function End Class @Ani By that same logic I could implement the method as such Class PersonList Inherits List(Of Person) Function FindByName(Name) as PersonList End Function Function FindByAge(Age) as PersonList End Function Function FindBySocialSecurityNumber(SocialSecurityNumber) as PersonList End Function End Class And call it as such Dim res as PersonList = MyList.FindByName("Max").FindByAge(25).FindBySocialSecurityNumber(1234) and the result along with the amount of code and its reusability is largely the same, no? I am not arguing just trying to understand.

  Read the article

• .NET MissingMethodException occuring on one of thousands of end-user machines -- any insight?

  - by Yoooder

  This issue has me baffled, it's affecting a single user (to my knowledge) and hasn't been reproduced by us... The user is receiving a MissingMethodException, our trace file indicates it's occuring after we create a new instance of a component, when we're calling an Initialize/Setup method in preparation to have it do work (InitializeWorkerByArgument in the example) The Method specified by the error is an interface method, which a base class implements and classes derived from the base class can override as-needed The user has the latest release of our application All the provided code is shipped within a single assembly Here's a very distilled version of the component: class Widget : UserControl { public void DoSomething(string argument) { InitializeWorkerByArgument(argument); this.Worker.DoWork(); } private void InitializeWorkerByArgument(string argument) { switch (argument) { case "SomeArgument": this.Worker = new SomeWidgetWorker(); break; } // The issue I'm tracking down would have occured during "new SomeWidgetWorker()" // and would have resulted in a missing method exception stating that // method "DoWork" could not be found. this.Worker.DoWorkComplete += new EventHandler(Worker_DoWorkComplete); } private IWidgetWorker Worker { get; set; } void Worker_DoWorkComplete(object sender, EventArgs e) { MessageBox.Show("All done"); } } interface IWidgetWorker { void DoWork(); event EventHandler DoWorkComplete; } abstract class BaseWorker : IWidgetWorker { virtual public void DoWork() { System.Threading.Thread.Sleep(1000); RaiseDoWorkComplete(this, null); } internal void RaiseDoWorkComplete(object sender, EventArgs e) { if (DoWorkComplete != null) { DoWorkComplete(this, null); } } public event EventHandler DoWorkComplete; } class SomeWidgetWorker : BaseWorker { public override void DoWork() { System.Threading.Thread.Sleep(2000); RaiseDoWorkComplete(this, null); } }

  Read the article

• C# Virtual method call in constructor - how to refactor?

  - by Cristi Diaconescu

  I have an abstract class for database-agnostic cursor actions. Derived from that, there are classes that implement the abstract methods for handling database-specific stuff. The problem is, the base class ctor needs to call an abstract method - when the ctor is called, it needs to initialize the database-specific cursor. I know why this shouldn't be done, I don't need that explanation! This is my first implementation, that obviously doesn't work - it's the textbook "wrong way" of doing it. The overridden method accesses a field from the derived class, which is not yet instantiated: public abstract class CursorReader { private readonly int m_rowCount; protected CursorReader() { m_rowCount = CreateCursor(sqlCmd); //virtual call ! } protected abstract int CreateCursor(string sqlCmd); } public class SqlCursorReader : CursorReader { private SqlConnection m_sqlConnection; public SqlCursorReader(string sqlCmd, SqlConnection sqlConnection) { m_sqlConnection = sqlConnection; //field initialized here } protected override int CreateCursor(string sqlCmd) { //uses not-yet-initialized member *m_sqlConnection* //so this throws a NullReferenceException var cursor = new CustomCursor(sqlCmd, m_sqlConnection); return cursor.Count(); } } I will follow up with an answer on my attempts to fix this...

  Read the article

• Recursive problem...

  - by Chronos

  Guys, I'm new to java and multithreading..... and I have a following problem: I have two classes running in two different threads. Class A and Class B. Class A has the method "onNewEvent()". Once that method is invoked, it will ask class B to do some work. As soon as B finishes the work it invokes onJobDone() method of the class A. Now... here comes the problem... what I want is to create new job within onJobDone() method and to send it again to B. here is what I do (pseudo code) ... in the sequence of execution A.onNewEvent(){ //create job //ask B to do it B.do() } B.do{ // Do some stuff A.jobDone() } A.onJobDOne(){ B.do() //doItAgain // print message "Thank you for doing it" } The problem is... that message "Thank you for doing it" never gets printed... in fact, when onJobDone() method is invoked, it invokes B.do()... because B.do() is very fast, it invokes onJobDone() immediatly... so execution flow never comes to PRINT MESSAGE part of code... I suppose this is one of the nasty multithreading problems.... any help would be appreciated.

  Read the article

• Does className exist in Mootools ?

  - by anna mae

  Hi, I want to update this very simple JS to Mootools 1.2 and it's not easy. This function : function changeclass(x){ document.getElementById("content").className = "ziclass0"; document.getElementById("content").className = "ziclass" + x; } is triggered in the DOM by : <div id="someclass"> a href="javascript: changeclass(0)">Unstyled</a a href="javascript: changeclass(1)">link one</a a href="javascript: changeclass(2)">link two</a a href="javascript: changeclass(3)">link three</a </div> to call the according CSS classes like : .ziclass1 h1{ color: rgb(142,11,0); font-family: Verdana; font-size: 2.5em; letter-spacing: 0.1em; } and changes the layout accordingly in : <div id="content" class="ziclass3"> ... </div> I know I can add an event to the triggers like : $(#someclass.each(function(element,index) { element.addEvent('click', function(){ //some code }); But, how do I get #content class classname ? Through an array ? I am a bit confused here. I'd be really grateful for any help to set me on the right track

  Read the article

• My QFileSystemModel doesn't work as expected in PyQt

  - by Skilldrick

  I'm learning the Qt Model/View architecture at the moment, and I've found something that doesn't work as I'd expect it to. I've got the following code (adapted from Qt Model Classes): from PyQt4 import QtCore, QtGui model = QtGui.QFileSystemModel() parentIndex = model.index(QtCore.QDir.currentPath()) print model.isDir(parentIndex) #prints True print model.data(parentIndex).toString() #prints name of current directory childIndex = model.index(0, 0, parentIndex) print model.data(childIndex).toString() rows = model.rowCount(parentIndex) print rows #prints 0 (even though the current directory has directory and file children) The question: Is this a problem with PyQt, have I just done something wrong, or am I completely misunderstanding QFileSystemModel? According to the documentation, model.rowCount(parentIndex) should return the number of children in the current directory. The QFileSystemModel docs say that it needs an instance of a Gui application, so I've also placed the above code in a QWidget as follows, but with the same result: import sys from PyQt4 import QtCore, QtGui class Widget(QtGui.QWidget): def __init__(self, parent=None): QtGui.QWidget.__init__(self, parent) model = QtGui.QFileSystemModel() parentIndex = model.index(QtCore.QDir.currentPath()) print model.isDir(parentIndex) print model.data(parentIndex).toString() childIndex = model.index(0, 0, parentIndex) print model.data(childIndex).toString() rows = model.rowCount(parentIndex) print rows def main(): app = QtGui.QApplication(sys.argv) widget = Widget() widget.show() sys.exit(app.exec_()) if __name__ == '__main__': main()

  Read the article

• Extracting function declarations from a PHP file

  - by byronh

  I'm looking to create an on-site API reference for my framework and application. Basically, say I have a class file model.class.php: class Model extends Object { ... code here ... // Separates results into pages. // Returns Paginator object. final public function paginate($perpage = 10) { ... more code here ... } } and I want to be able to generate a reference that my developers can refer to quickly in order to know which functions are available to be called. They only need to see the comments directly above each function and the declaration line. Something like this (similar to a C++ header file): // Separates results into pages. // Returns Paginator object. final public function paginate($perpage = 10); I've done some research and this answer looked pretty good (using Reflection classes), however, I'm not sure how I can keep the comments in. Any ideas? EDIT: Sorry, but I want to keep the current comment formatting. Myself and the people who are working on the code hate the verbosity associated with PHPDocumentor. Not to mention a comment-rewrite of the entire project would take years, so I want to preserve just the // comments in plaintext.

  Read the article

• Searching in an Arraylist

  - by Puchatek

  Currently I have two classes. A Classroom class and a School class. I would like to write a method in the School class public void showClassRoomDetails which would find the classroom details by only using the teacherName. e.g. teacherName = Daniel className = Science teacherName = Bob className = Maths so when I input Bob, it would print out Bob and Maths many, thanks public class Classroom { private String classRoomName; private String teacherName; public void setClassRoomName(String newClassRoomName) { classRoomName = newClassRoomName; } public String returnClassRoomName() { return classRoomName; } public void setTeacherName(String newTeacherName) { teacherName = newTeacherName; } public String returnTeacherName() { return teacherName; } } import java.util.ArrayList; public class School { private ArrayList<Classroom> classrooms; private String classRoomName; private String teacherName; public School() { classrooms = new ArrayList<Classroom>(); } public void addClassRoom(Classroom newClassRoom, String theClassRoomName) { classrooms.add(newClassRoom); classRoomName = theClassRoomName; } public void addTeacherToClassRoom(int classroomId, String TeacherName) { if (classroomId < classrooms.size() ) { classrooms.get(classroomId).setTeacherName(TeacherName); } } public void showClassRoomDetails { //loop System.out.println(returnClassRoomName); System.out.println(returnTeacherName); } }

  Read the article

• How can I get type information at runtime from a DMP file in a Windbg extension?

  - by pj4533

  This is related to my previous question, regarding pulling objects from a dmp file. As I mentioned in the previous question, I can successfully pull object out of the dmp file by creating wrapper 'remote' objects. I have implemented several of these so far, and it seems to be working well. However I have run into a snag. In one case, a pointer is stored in a class, say of type 'SomeBaseClass', but that object is actually of the type 'SomeDerivedClass' which derives from 'SomeBaseClass'. For example it would be something like this: MyApplication!SomeObject +0x000 field1 : Ptr32 SomeBaseClass +0x004 field2 : Ptr32 SomeOtherClass +0x008 field3 : Ptr32 SomeOtherClass I need someway to find out what the ACTUAL type of 'field1' is. To be more specific, using example addresses: MyApplication!SomeObject +0x000 field1 : 0cae2e24 SomeBaseClass +0x004 field2 : 0x262c8d3c SomeOtherClass +0x008 field3 : 0x262c8d3c SomeOtherClass 0:000> dt SomeBaseClass 0cae2e24 MyApplication!SomeBaseClass +0x000 __VFN_table : 0x02de89e4 +0x038 basefield1 : (null) +0x03c basefield2 : 3 0:000> dt SomeDerivedClass 0cae2e24 MyApplication!SomeDerivedClass +0x000 __VFN_table : 0x02de89e4 +0x038 basefield1 : (null) +0x03c basefield2 : 3 +0x040 derivedfield1 : 357 +0x044 derivedfield2 : timecode_t When I am in WinDbg, I can do this: dt 0x02de89e4 And it will show the type: 0:000> dt 0x02de89e4 SomeDerivedClass::`vftable' Symbol not found. But how do get that inside an extension? Can I use SearchMemory() to look for 'SomeDerivedClass::`vftable'? If you follow my other question, I need this type information so I know what type of wrapper remote classes to create. I figure it might end up being some sort of case-statement, where I have to match a string to a type? I am ok with that, but I still don't know where I can get that string that represents the type of the object in question (ie SomeObject-field1 in the above example).

  Read the article

• Structuring the UI code of a single-page EXTjs Web app using Rails?

  - by Daniel Beardsley

  I’m in the process of creating a large single-page web-app using ext-js for the UI components with Rails on the backend. I’ve come to good solutions for transferring data using Whorm gem and Rails support of RESTful Resources. What I haven’t come to a conclusion on is how to structure the UI and business logic aspects of the application. I’ve had a look at a few options, including Netzke but haven’t seen anything that I really think fits my needs. How should a web-application that uses ext-js components, layouts, and controls in the browser and Rails on the server best implement UI component re-use, good organization, and maintainability while maintaining a flexible layout design. Specifically I’m looking for best-practice suggestions for structuring the code that creates and configures UI components (many UI config options will be based on user data) Should EXT classes be extended in static JS for often re-used customizations and then instantiated with various configuration options by generated JS within html partials? Should partials create javascript blocks that instantiate EXT components? Should partials call helpers that return ruby hashes for EXT component config which is then dumped to Json? Something else entirely? There are many options and I'd love to hear from people who've been down this road and found some methodology that worked for them.

  Read the article

• ASP.NET MVC Viewmodel trouble...

  - by ile

  I've already started similar topic, but still didn't find final solution... So here I am with new one :) ... I'm developing NerdDinner from scratch and now I came to point where I define DinnerViewModel. Following these instructions (starting from Listing 5) I came to this: namespace Nerd.Controllers { // View Model Classes public class DinnerViewModel { public DinnerViewModel(List<Dinner> dinners) { this.Dinners = dinners; } public List<Dinner> Dinners { get; private set; } } public class DinnerController : Controller { private DinnerRepository dinnerRepository = new DinnerRepository(); .... public ActionResult NewDinners() { // Create list of products var dinners = new List<Dinner>(); dinners.Add(new Dinner(/*Something to add*/)); // Return view return View(new DinnerViewModel(dinners)); } } } Also, the Dinner table in this new version of NerdDinner is a bit shortened (it contains of DinnerID, Title, EventDate and Description fields). No matter what I try to add here dinners.Add(new Dinner(/*Something to add*/)); I always get following error Error 1 'Nerd.Model.Dinner' does not contain a constructor that takes '1' arguments C:\Documents and Settings\ilija\My Documents\Visual Studio 2008\Projects\Nerd\Nerd\Controllers\DinnerController.cs 150 25 Nerd Because I'm total beginner in C# and generally OOP, I have no idea what to do here... I suppose I need to declare a constructor, but how and where exactly? Thanks, Ile

  Read the article

• How can I refactor this to work without breaking the pattern horribly?

  - by SnOrfus

  I've got a base class object that is used for filtering. It's a template method object that looks something like this. public class Filter { public void Process(User u, GeoRegion r, int countNeeded) { List<account> selected = this.Select(u, r, countNeeded); // 1 List<account> filtered = this.Filter(selected, u, r, countNeeded); // 2 if (filtered.Count > 0) { /* do businessy stuff */ } // 3 if (filtered.Count < countNeeded) this.SendToSuccessor(u, r, countNeeded - filtered) // 4 } } Select(...), Filter(...) are protected abstract methods and implemented by the derived classes. Select(...) finds objects in the based on x criteria, Filter(...) filters those selected further. If the remaining filtered collection has more than 1 object in it, we do some business stuff with it (unimportant to the problem here). SendToSuccessor(...) is called if there weren't enough objects found after filtering (it's a composite where the next class in succession will also be derived from Filter but have different filtering criteria) All has been ok, but now I'm building another set of filters, which I was going to subclass from this. The filters I'm building however would require different params and I don't want to just implement those methods and not use the params or just add to the param list the ones I need and have them not used in the existing filters. They still perform the same logical process though. I also don't want to complicated the consumer code for this (which looks like this) Filter f = new Filter1(); Filter f2 = new Filter2(); Filter f3 = new Filter3(); f.Sucessor = f2; f2.Sucessor = f3; /* and so on adding filters as successors to previous ones */ foreach (User u in users) { foreach (GeoRegion r in regions) { f.Process(u, r, ##); } } How should I go about it?

  Read the article

• OnConnect event not firing when using TClientSocket inside a TThread on non-blocking mode

  - by mathematician1975

  I am trying to make use of Borlands TClientSocket component in non-blocking mode inside a multithreaded C++ Windows application. I am creating multiple threads (classes derived from TThread), each of which creates its own TClientSocket object. I then assign member functions of the thread class to act as event handlers for the OnConnect, OnDisconnect and OnSocketError events of the socket. The problem I am having here is that whenever I call the TClientSocket::Open() function from within the TThread::Execute() function, the OnConnect event never fires. However, When I call the Open() function from the VCL thread prior to the TThread::Execute() function getting called, all of the events fire and I can use the thread-socket combination as I would like. Now I have not read anything in documentation that says that TClientSocket should not be used in non-blocking mode when used inside a thread, but it appears to me that there is perhaps something wrong conceptually in the way I am trying to use this class. Borland documentation is quite poor on the subject and these components have now been deprecated so reliable information is hard to come by. Despite being deprecated I have to use them as there is no alternative in the Builder 6 package I have. Can anyone please advise me if there is a right/wrong way to use TThread and a non-blocking TClientSocket in combination. I have never had problems using it as part of the VCL thread and never had problems using TServerSocket before and I really cannot understand why some events are not firing.

  Read the article

• Problem creating XML using c#

  - by Pankaj

  I am searching a batter solution for creating xml through xml serialization. What i need, i have a given format like this <product Id="1"> <name>2 1/2 X 6 PVC NIPPLE TOE SCH 80</name> <notes> <note>!--note 1---</note> <note>!--note 2--</note> ...... </notes> </product> what i am doing here, i created a 2 classes like this public class product { [XmlElement("name")] public string Name { get; set; } [XmlArray("notes")] public List<notes> ListNotes { get; set; } } public class notes { [XmlIgnore] public string Note { get; set; } } when i am serializing this then i am getting xml in this formate <product Id="1"> <name>2 1/2 X 6 PVC NIPPLE TOE SCH 80</name> <notes> <notes> <note>!--note 1---</note> <note>!--note 2--</note> </notes> </notes> </product> i don't want extra <notes>. Any batter solution to solve this problem? Thanks

  Read the article

• Servlet doPost() Method setup?

  - by Mark R

  I am interested in creating a web app that uses JSP, Servlets and XML. At the moment I have the following: JSP - Form input. Servlet - Retrieving Form data and sending that data to a java object. Java object (1) - Converts data into XML file....instantiates java object (2). Java object (2) - Sends that file to a database. On the returning side the database will send back another XML file that I will then process using XSLT to display back to the user. Can I place that XSLT code in the orignial Servlets doPost() method? So my doPost()` method would: Retrieve user inputted data from the form on my JSP page. Instantiate a java object to convert that data to XML, in-turn that object will instantiates another object to send the XML file to a database. Converts the resulting XML file sent from the database and displays it for the user. Can one servlet doPost() method handle all of this? If not, how would I set up my application and classes to handle this work flow? Thank you in advance

  Read the article

• What makes an effective UI for displaying versioning of structured hierarchical data

  - by Fadrian Sudaman

  Traditional version control system are displaying versioning information by grouping Projects-Folders-Files with Tree view on the left and details view on the right, then you will click on each item to look at revision history for that configuration history. Assuming that I have all the historical versioning information available for a project from Object-oriented model perspective (e.g. classes - methods - parameters and etc), what do you think will be the most effective way to present such information in UI so that you can easily navigate and access the snapshot view of the project and also the historical versioning information? Put yourself in the position that you are using a tool like this everyday in your job like you are currently using SVN, SS, Perforce or any VCS system, what will contribute to the usability, productivity and effectiveness of the tool. I personally find the classical way for display folders and files like above are very restrictive and less effective for displaying deep nested logical models. Assuming that this is a greenfield project and not restricted by specific technology, how do you think I should best approach this? I am looking for idea and input here to add values to my research project. Feel free to make any suggestions that you think is valuable. Thanks again for anyone that shares their thoughts.

  Read the article

• Help with Java Generics: Cannot use "Object" as argument for "? extends Object"

  - by AniDev

  Hello, I have the following code: import java.util.*; public class SellTransaction extends Transaction { private Map<String,? extends Object> origValueMap; public SellTransaction(Map<String,? extends Object> valueMap) { super(Transaction.Type.Sell); assignValues(valueMap); this.origValueMap=valueMap; } public SellTransaction[] splitTransaction(double splitAtQuantity) { Map<String,? extends Object> valueMapPart1=origValueMap; valueMapPart1.put(nameMappings[3],(Object)new Double(splitAtQuantity)); Map<String,? extends Object> valueMapPart2=origValueMap; valueMapPart2.put(nameMappings[3],((Double)origValueMap.get(nameMappings[3]))-splitAtQuantity); return new SellTransaction[] {new SellTransaction(valueMapPart1),new SellTransaction(valueMapPart2)}; } } The code fails to compile when I call valueMapPart1.put and valueMapPart2.put, with the error: The method put(String, capture#5-of ? extends Object) in the type Map is not applicable for the arguments (String, Object) I have read on the Internet about generics and wildcards and captures, but I still don't understand what is going wrong. My understanding is that the value of the Map's can be any class that extends Object, which I think might be redundant, because all classes extend Object. And I cannot change the generics to something like ? super Object, because the Map is supplied by some library. So why is this not compiling? Also, if I try to cast valueMap to Map<String,Object>, the compiler gives me that 'Unchecked conversion' warning. Thanks!

  Read the article

• How to create XSD schema from XML with this kind of structure (in .net)?

  - by Mr. Brownstone

  Here's the problem: my input is XML file that looks something like: <BaseEntityClassInfo> <item> <key>BaseEntityClassInfo.SomeField</key> <value>valueData1</value> </item> <item> <key>BaseEntityClassInfo.AdditionalDataClass.SomeOtherField</key> <value>valueData2</value> </item> <item> <key>BaseEntityClassInfo.AdditionalDataClass.AnotherClassInfo.DisplayedText</key> <value>valueData3</value> </item> ... ... </BaseEntityClassInfo> The <key> element somehow describes entity classes fields and relationships (used in some other app that I don't have access to) and the <value> stores the actual data that I need. My goal is to programatically generate a typed Dataset from this XML that could then be used for creating reports. I thought of building some XSD schema from input XML file first and then use this schema to generate Dataset but I'm not sure how to do that. The problem is that I don't want all data in one table, I need several tables with relationships based on the <key> value so I guess I need to infer relational structure from XML <key> data in some way. So what do you think? How could this be done and what would be the best approach? Any advice, ideas, suggestions would be appreciated!

  Read the article

• Javascript Getting Objects to Fallback to One Another

  - by Ian

  Here's a ugly bit of Javascript it would be nice to find a workaround. Javascript has no classes, and that is a good thing. But it implements fallback between objects in a rather ugly way. The foundational construct should be to have one object that, when a property fails to be found, it falls back to another object. So if we want a to fall back to b we would want to do something like: a = {sun:1}; b = {dock:2}; a.__fallback__ = b; then a.dock == 2; But, Javascript instead provides a new operator and prototypes. So we do the far less elegant: function A(sun) { this.sun = sun; }; A.prototype.dock = 2; a = new A(1); a.dock == 2; But aside from elegance, this is also strictly less powerful, because it means that anything created with A gets the same fallback object. What I would like to do is liberate Javascript from this artificial limitation and have the ability to give any individual object any other individual object as its fallback. That way I could keep the current behavior when it makes sense, but use object-level inheritance when that makes sense. My initial approach is to create a dummy constructor function: function setFallback(from_obj, to_obj) { from_obj.constructor = function () {}; from_obj.constructor.prototype = to_obj; } a = {sun:1}; b = {dock:2}; setFallback(a, b); But unfortunately: a.dock == undefined; Any ideas why this doesn't work, or any solutions for an implementation of setFallback? (I'm running on V8, via node.js, in case this is platform dependent)

  Read the article

• Using reflection to find all linq2sql tables and ensure they match the database

  - by Jake Stevenson

  I'm trying to use reflection to automatically test that all my linq2sql entities match the test database. I thought I'd do this by getting all the classes that inherit from DataContext from my assembly: var contexttypes = Assembly.GetAssembly(typeof (BaseRepository<,>)).GetTypes().Where( t => t.IsSubclassOf(typeof(DataContext))); foreach (var contexttype in contexttypes) { var context = Activator.CreateInstance(contexttype); var tableProperties = type.GetProperties().Where(t=> t.PropertyType.Name == typeof(ITable<>).Name); foreach (var propertyInfo in tableProperties) { var table = (propertyInfo.GetValue(context, null)); } } So far so good, this loops through each ITable< in each datacontext in the project. If I debug the code, "table" is properly instantiated, and if I expand the results view in the debugger I can see actual data. BUT, I can't figure out how to get my code to actually query that table. I'd really like to just be able to do table.FirstOrDefault() to get the top row out of each table and make sure the SQL fetch doesn't fail. But I cant cast that table to be anything I can query. Any suggestions on how I can make this queryable? Just the ability to call .Count() would be enough for me to ensure the entities don't have anything that doesn't match the table columns.

  Read the article

• tomcat resource missing, servlet not running

  - by user2837260

  import javax.servlet.*; import java.io.*; public class MyServlet implements Servlet { public void init(ServletConfig con) {} public void service(ServletRequest req, ServletResponse res) throws IOException,ServletException { res.setContentType("text/html"); PrintWriter out=res.getWriter(); String s="blah"; String s1="blah"; out.println("<html><body>"); if((s.equals(req.getParameter("firstname")))&&(s1.equals(req.getParameter("pwd")))) out.println("passwords match"); else out.println("password and name combo does not match"); out.println("</body></html>"); } public void destroy() {} public ServletConfig getServletConfig() { return null;} public String getServletInfo() { return null;} } this is my java file with the servlet class.its saved with the name MyServlet.java and so is the class file. and here is the xml file: <web-app> <servlet> <servlet-name>demoo</servlet-name> <servlet-class>MyServlet</servlet-class> </servlet> <servlet-mapping> <servlet-name>demoo</servlet-name> <url-pattern>/demo</url-pattern> </servlet-mapping> </web-app> i have made the folder as WEB-INF and then classes... WEB-INF also contains the .xml file but when i try to run the servlet , it says resource not found ps- i am already looking for the servlet with the name :demo localhost:8081/s1/demo* s1 is the war file * a html file in the war file seems to run fine on the server though. *

  Read the article

• How to create a platform ontop of CSLA? <-- if in case it make sense

  - by Peejay

  Hi all! here is the senario, i'm developing an application using csla 3.8 / c#.net, the application will have different modules. its like an ERP, it will have accounting, daily time record, recruitment etc as modules. Now the requirement is to check for common entities per module and build a "platform" (<- the boss calls it that way) from it. for example, DTR will have an entity "employee", Recruitment will have "Applicant" so one common entity that you can derive from both that can be put in the platform is "Person". "Person" will contain typical info like name, address, contact info etc. I know it sounds like OOP 101. the thing is, i dont know how i am to go about it. how i wish it was just a simple inheritance but the requirement is like to create an API of some sort to be used by the modules using CSLA. in csla you create smart objects right, inheriting from the base classes of csla like businessListbase, readonlylistbase etc. right? what if for example i created a businessbase Applicant class, it will have properties like salary demand, availability date etc. now for the personal info i will need the "Person" from the "platform" and implement it to the applicant class. so in summary i have several questions: how to create such platform? if such platform is possible, how will it be implemented on each module's entities? (im already inheriting from base clases of csla) if incase 1 and 2 are possible, does it have advantages on development and maintenace of the app? the reason why i'm asking #3 is because the way i see it, even if i am able to create a platform for that, i will be needing to define properties of the platform entity on my module entities so to have validation and all. im sorry if i'm typing nonesense i'm really confused. hope someone could enlighten me. thank you all!

  Read the article

• Problem with 2 levels of inheritance in hibernate mapping

  - by Seth

  Here's my class structure: class A class B extends A class C extends A class D extends C class E extends C And here are my mappings (class bodies omitted for brevity): Class A: @Entity @Inheritance(strategy=InheritanceType.SINGLE_TABLE) @MappedSuperclass @DiscriminatorColumn( name="className", discriminatorType=DiscriminatorType.STRING ) @ForceDiscriminator public abstract class A Class B: @Entity @DiscriminatorValue("B") public class B extends A Class C: @Entity @DiscriminatorValue("C") @MappedSuperclass @DiscriminatorColumn( name="cType", discriminatorType=DiscriminatorType.STRING ) @ForceDiscriminator public abstract class C extends A Class D: @Entity @DiscriminatorValue("D") public class D extends C Class E: @Entity @DiscriminatorValue("E") public class E extends C I've got a class F that contains a set of A: @Entity public class F { ... @OneToMany(fetch=FetchType.LAZY, cascade=CascadeType.ALL) @JoinTable( name="F_A", joinColumns = @JoinColumn(name="A_ID"), inverseJoinColumns = @JoinColumn(name="F_ID") ) private Set<A> aSet = new HashSet<A>(); ... The problem is that whenever I add a new E instance to aSet and then call session.saveOrUpdate(fInstance), hibernate saves with "A" as the discrimiator string. When I try to access the aSet in the F instance, I get the following exception (full stacktrace ommitted for brevity): org.hibernate.InstantiationException: Cannot instantiate abstract class or interface: path.to.class.A Am I mapping the classes incorrectly? How am I supposed to map multiple levels of inheritance? Thanks for the help!

  Read the article

< Previous Page | 467 468 469 470 471 472 473 474 475 476 477 478  | Next Page >