abstract-factory

问题 I know there are many posts out there about the differences between these two patterns, but there are a few things that I cannot find. From what I have been reading, I see that the factory method pattern allows you to define how to create a single concrete product but hiding the implementation from the client as they will see a generic product. My first question is about the abstract factory. Is its role to allow you to create families of concrete objects in (that can depend on what specific

问题 My objective is to run a never ending process in a parallel thread. The problem is, I cannot just instantiate my worker service in the new Thread, because I am using DI in my application. Based on my research here on SO, I have noticed many people are suggesting that Abstract Factories need to be injected into the thread to dynamically instantiate a thread-safe object in a parallel thread. 1, 2 /// <summary> /// Responsible for starting parallel long running worker threads /// </summary>

问题 As usual to build the project with different design patterns, architects always prefer the advantageous view of that particular design pattern. But sometimes it need to understand what should be the violation area and disadvantages in terms of future extension of project. I am using Abstract factory design pattern now a days. I understood it but unable to figure out its disadvantages,its limitations, where it will get fail. can somebody please explain me this another view of Abstract Factory

问题 Sorry for asking again. I have searched over web but couldn't understand hence i have to put here. Here what I research by my self. I studied from head first design pattern. Abstract factory pattern : As per the differences i studied that builder some senses it is a Factory, but it only creates one type, most of the time. So can i say NYStore in above image is builder as it returns pizza object to client? am i correct? Please give your answer on bases of above example which may help me to

问题 I'm rethinking a current WCF service we're using right now. We do A LOT of loading XML to various databases. In some cases, we can store it as XML data, and in others, we need to store it as rowsets. So I'm redesigning this service to accept different providers. My first thought, classic abstract factory, but now I'm having my doubts. Essentially, the service class has one operation contract method, Load. But to me, it seems silly to new-up provider instances every time Load is called.

问题 This question already has answers here : What are the differences between Abstract Factory and Factory design patterns? (16 answers) Closed 5 years ago . I have read about Factory Method where Sub class creates needed Object and Abstract Factory has methods where concrete classes creates needed Object Factory Method public class PizzaStore { public Pizza orderPizza(String type) { Pizza pizza = createPizza(type); pizza.prepare(); pizza.bake(); pizza.cut(); } abstract Pizza createPizza(String

问题 I am implementing the AbstractFactory pattern allowing outsiders to create Factories. I am reading the factory implementation name from a properties file, loading the factory class and using it to construct objects. Problem is that somewhere in my factory implementation when I'm trying to create an object of a task I get the following error: Exception in thread "Thread-1" java.lang.ClassFormatError: Code segment has wrong length in class file com/testsuite/loadperformancetesterusage/tasks

问题 I was studying the design patterns and came across Abstract Factory Pattern which by definition is : Abstract Factory Pattern says that just define an interface or abstract class for creating families of related (or dependent) objects but without specifying their concrete sub-classes.That means Abstract Factory lets a class returns a factory of classes. But I am not able to understand it thoroughly. I even went through some examples given in this link and this question, but nothing helped.

问题 I think the original use of the abstract factory pattern is when you want to create a family of related objects. This is what is described in Gang of Four (GoF) and this tutorial: http://www.oodesign.com/abstract-factory-pattern.html I keep also seeing posts that the abstract factory pattern can be used for dependency injection, particulary for injecting values that are worked out at runtime. All the uses of abstract factory pattern given here seem to be referring to this method: Why do we

问题 CodeCampServer source code contains a generic StaticFactory. I'm surmising that this is a key piece of the mechanism for how the framework plays well with Dependency Injection. Subclasses of which use it's DefaultUnconfiguredState to provide static access to, well, a Default Unconfigured State for themselves which the dependency resolution mechanism can replace with working stuff. I've not been able to find any documentation for this... Is there a good explanation in the book? (I'm awaiting