随笔分类 -  Design patterns

摘要：Function:Provide an interface for creating families of related or dependent objects without specifying their concrete classes. Participants:AbstractFactory(ContinentFactory) declares an interface for ... 阅读全文

摘要：Function:Lets subclasses redefine certain steps of an algorithm without changing the algorithm's structureActor: 阅读全文

摘要：Function: Make sure that in an application exists only one instance of a class.Actors: 阅读全文

摘要：Function:A facade is an object that provides a simplified interface to a larger body of code, such as a class library. A facade can:make a software library easier to use and understand, since the faca... 阅读全文

摘要：Function:The decorator pattern can be used to make it possible to extend (decorate) the functionality of a class at runtime.Actors:FunctionInterface, BasicFunctionClass, decorator, concreteDecoratorSu... 阅读全文

摘要：Function: Decouple the object that invokers the operation, by creating class for operations.Actors:Client, Invoker, command, concreteCommand, receiverSummary: 阅读全文

摘要：Function:Create a new interface(like a adapter or wrapper) between client and class of library. So when use another library, just need to modify the adapter without letting the client knows the change... 阅读全文

摘要：访问者 visitor的本质是创建若干个各个类型Element的子类SubElement，子类中提供visit(Vistior v)方法，因为SubElement知道自己的类型，所以可以在visit(v)方法中自己决定visitor调用哪个方法来处理SubElement.而不需要在Visitor中根据Element的类型来判断需要执行哪个方法 (instanceof) 阅读全文