interface

问题 I'm making a change to an API that serves data. Some of the searches require data about an author and take a IAuthor object. The API has an IAuthor interface and a single concrete class that implements IAuthor called Author . I need to add a boolean property, IsNovelist that will change the semantics of some but not all searches. I've heard about the open/closed principle and it would seem that changing the IAuthor and/or Author classes would violate this. How then to make this simple change?

问题 Im having problems with making a good interface and use it... My setup overview: An "interface" GraphicsLibrary.H ... virtual void drawPoint(const Point& p, unsigned char r, unsigned char g, unsigned char b, double pointSize); with an "empty" GraphicsLibrary.ccp! because its an interface, so "OpenGL" is an graphics library... so i have an OpenGL.CPP with: void GraphicsLibrary::drawPoint(const Point& p, unsigned char r, unsigned char g, unsigned char b, double pointSize) { //some code } which

问题 I need to understand Interface : I have this structure : Core (contain Interface) BLL (Contain object who implement interface DAL (Contain Data access) IHM (Call BLL object) For example, i have an Interface Core.IVehicle who describe a basic vehicle like : Color Speed And a one method : LoadVehicle(int id) //return a iVehicule with speed and color In my BLL, I have an object "BLL.Car" who implement "Core.IVehicle". So, i will have a LoadVehicle method and access to DALfor get basics

问题 Update based on inputs below. Now and again I feel efforts for type-safe use of Java interfaces less than straightforward. Here's a simple example of what we'd like to do: a design, following. When it comes to implementation after several attempts to get type safety, I'm ( again ) discovering that we need to think in Java to encourage Java to support our needs. I'm made improvements on the original example. I'm leaving the question open because there's probably a better way to go about things

问题 I have an abstract class X and some classes who extend this class, call them A , B and C . In some other class Y I have a few methodcalls that depend on the type of the class. The if-else statement looks like this: public class Y implements InterfaceY { public Y(){ } public String doStuff (X x, Boolean flag) { String s = ""; if (x instanceof A) { doStuff((A) x)); } else if (x instanceof B) { doStuff((B) x)); } else if (x instanceof C) { doStuff((C) x, flag); } else { throw new Exeption(); }

问题 I'm pretty sure I have tried everything. I have a tabbed activity utilizing 6 fragments within a viewpager. Part of the layout includes a FINISH button within the parent activity, that once clicked should call 6 methods, one in each fragment, from 1-6. For the life of me nothing seems to be able to work. What I have tried: 1) Creating a button onclicklistener for the finish button within each fragment and calling the methods. It only calls the method in the first fragment and does not seem to

问题 interface A { string Name {get;set;}} interface B { string Name {get;set;}} class C : A, B { string A.Name {get;set;} string B.Name {get;set;}} var c = new C(); ((A)c).Name = "a"; ((B)c).Name = "b"; var s = JsonConvert.SerializeObject(c); The result is an empty json object with no property values. Is it possible to serialize and deserialize such an object? 回答1: Tell json to serialize private properties: class C : A, B { [JsonProperty] string A.Name { get; set; } [JsonProperty] string B.Name {

问题 so I'm currently creating a unit test for a class that I've implemented a few weeks ago. I'll show you first the particular part of the class where I'm working on. public void PostEvent(eVtCompId inSenderComponentId, eVtEvtId inEventId, long inEventReference, IF_SerializableData inEventData) { if(mEventMap.ContainsKey(inEventId)) { mEventMap[inEventId](inSenderComponentId, inEventReference, inEventData); } } For this method, I have 4 parameters. 1st, an enum; 2nd, another enum; 3rd, long; 4th

问题 I'm trying to create a scenario on my Macbook with Mojave in Anylogic, which is part of agent-based simulation with many different tools. My idea is to connect Anylogic via Java Interface to Eclipse. The main problem is, that Anylogic somehow does not respond. I have tried many different codes with sockets, but could not find one, which worked for Anylogic. I'm using the free version of Anylogic and created a Java Interface under my Main Project. To run the Java Interface I press right-click

问题 I have two distinct (no inheritance) interfaces: IInvestable and IPricable and two classes: IndexClass and FundClass that are stored in seperate tables in my DB. IndexClass is IPriceable FundClass is IPriceable and IInvestable . I need a table to store prices against an IndexClass and a FundClass I need a table to store that FundClasses are invested in. One way might be to have two tables: Pricable and Investable which just have an ID column. Then have a foreign key on IndexClass : PricableID