factory-pattern

I'm writing a framework for querying the Mediawiki API . I have a Page class which represents articles on the wiki, and I've also got a Category class, which is-a Page with more specific methods (like being able to count the number of members in the category. I've also got a method Page#category? which determines if an instantiated Page object is actually representative of a Mediawiki category page, by querying the API to determine the namespace of the article. class Page def initialize(title) # do initialization stuff end def category? # query the API to get the namespace of the page and then

I have a problem that I’ve tried to get help for before, but I wasn’t able to solve it then, so I’m trying to simplify the problem now to see if I can get some more concrete help with this because it is driving me crazy… Basically, I have a working (more complex) version of this application, which is a project cost calculator. But because I am at the same time trying to learn to design my applications better, I would like some input on how I could improve this design. Basically the main thing I want is input on the conditionals that (here) appear repeated in two places. The suggestions I got

I am learning design patterns newly & I am trying to understand the difference between Simple Factory & Factory Method Pattern. First I want to clear that , I tried reading lot of articles from Stack-overflow and other sites regarding the same but that doesn't helped me. Here is my question: Lets consider I have a product hierarchy as shown below: I have written a simple Factory class as shown below public class SimpleItemFactory { static Item getItem(String type) { if(type.equals("Cake")) { return new Cake(); }else if(type.equals("Chocolate")) { return new Chocolate(); }else { return null; }

I've got a factory method inside a parser. Essentially as I load a token I look up the handler for that token, or drop through to the default handler. I've implemented this as a switch and as a Dictionary<string,Type> but both approaches require me to store the mapping somewhere else than the handler class. We are using Ninject for IOC and so I've realized I can also do it using kernel.Get<ITokenHandler>(tokenName); but that doesn't save me storing the information on what token the handler can deal with in 2 locations. Is there a way I can decorate the handler so this gets mapped automatically

I have a Data Access Layer library that I would like to make "portable". The reason I like it to be portable is because I want to work with SQL Azure & Azure File Storage (eg, data + pdf reports) as well as Sql Server 2008R2 and File System storage on a concrete server. Based on spec the system is supposed to go live with the later implementation (sql + file system storage), while upon a meeting a certain scalability threshold we plan on moving to Azure. The data access class I use implements IDataProvider interface (which I built) and it defines the methods that any data access concrete

Which way use of Factory is better(correct)? IPacket info = PacketFactory.CreatePacketObject(PacketType.Info, currentUser, DateTime.Now, " disconnected"); or should I throw out second method in PacketFactory and use this one? IPacket info = PacketFactory.CreatePacketObject(PacketType.Info); info.CreationTime = DateTime.Now; info.Creator = currentUser; info.Data = " disconnected"; or maybe some other? PacketFactory code: public static class PacketFactory { public static IPacket CreatePacketObject(PacketType type) { IPacket packetToCreate = null; switch (type) { case PacketType.Info:

I want to change the object return from call to a constuctor FROM public class A { public A(){ } public String sayHello() { return "hello"; } public String foo() { return "foo"; } } TO public class AWrapped extends A { private A wrapped; public AWrapped() { super(); } public AWrapped(A pWrapped) { wrapped=pWrapped; } public String foo() { return wrapped.foo(); } public String sayHello { return "gday mate"; } } What i want to do is to change the object that is returned from a call A a = new A(); a.sayHello() returns "gday mate" a is an instaceof AWrapped I understand that this would usually be