factory-method

问题 What is the difference between the Builder design pattern and the Factory design pattern? Which one is more advantageous and why ? How do I represent my findings as a graph if I want to test and compare/contrast these patterns ? 回答1: With design patterns, there usually is no "more advantageous" solution that works for all cases. It depends on what you need to implement. From Wikipedia: Builder focuses on constructing a complex object step by step. Abstract Factory emphasizes a family of

问题 Note: Questions are at the end of the post. I have read the other stackoverflow threads regarding Abstract Factory vs Factory Method . I understand the intent of each pattern. However, I am not clear on the definition. Factory Method defines an interface for creating an object, but lets subclasses decide which of those to instantiate. A factory method lets classes defer instantiation to subclasses. By contrast, an Abstract Factory provides an interface for creating families of related or

问题 There\'s this one thing in C++ which has been making me feel uncomfortable for quite a long time, because I honestly don\'t know how to do it, even though it sounds simple: How do I implement Factory Method in C++ correctly? Goal: to make it possible to allow the client to instantiate some object using factory methods instead of the object\'s constructors, without unacceptable consequences and a performance hit. By \"Factory method pattern\", I mean both static factory methods inside an

问题 When is it a good idea to use factory methods within an object instead of a Factory class? 回答1: I like thinking about design pattens in terms of my classes being 'people,' and the patterns are the ways that the people talk to each other. So, to me the factory pattern is like a hiring agency. You've got someone that will need a variable number of workers. This person may know some info they need in the people they hire, but that's it. So, when they need a new employee, they call the hiring

问题 I was reading design patterns from a website There I read about Factory, Factory method and Abstract factory but they are so confusing, am not clear on the definition. According to definitions Factory - Creates objects without exposing the instantiation logic to the client and Refers to the newly created object through a common interface. Is a simplified version of Factory Method Factory Method - Defines an interface for creating objects, but let subclasses to decide which class to

问题 What\'s a \"static factory\" method? 回答1: We avoid providing direct access to database connections because they're resource intensive. So we use a static factory method getDbConnection that creates a connection if we're below the limit. Otherwise, it tries to provide a "spare" connection, failing with an exception if there are none. public class DbConnection{ private static final int MAX_CONNS = 100; private static int totalConnections = 0; private static Set<DbConnection>