Consider this simple code: class A {} class B extends A {} public class TestClass { public static void main(String args[]) { A[] a, a1; B[] b; a = new A[10]; a1 = a; b = new B[20]; a = b; // 1 b = (B[]) a; // 2 b = (B[]) a1; // 3 } } Look closely at
I don't have access to the definition of a class but I can inherit from it. I want in the derived class to be denied from accessing some fields that are public in the base class for obvious reasons of accidentally accessing/setting/getting the fields
I'd like to have Table Per Concrete type inheritance in my application: public class Row { public int Id {get;set;} public string Name {get;set;} } public class ExtendedRow : Row { public int Weight {get;set;} } Each of the classes need to be mapped
EDIT Ive rephrased the question so it better reflects what im trying to do I'm trying to create a suite of classes that all inherit from 1 "superclass" or "baseclass". However i'm looking for a way around having to implement the code f
Let's say I have object Cat in a node module. I want to replace the Cat function itself and not it's prototypes. To put it another way I want to take the prototoypes from one object and add them to another. function Cat(name, breed){ this.name = name
Is there any advantage to calling the parent constructor explicitly in the derived class constructor? is this: LockableDoor :: LockableDoor() : Door(), locked_(true) { } is different from this: LockableDoor :: LockableDoor() : locked_(true) { } someh
(Removed original text as it is unrelated to the current question which has already been answered. See revisions.) Here is my example test.hpp (simplified): class House { private: int nWindows; public: House(int nWindows); int getNumberOfWindows(); }
Especially in unittests we use this "design pattern" I call "get class from class level" framworktest.py: class FrameWorkHttpClient(object): .... class FrameWorkTestCase(unittest.TestCase): # Subclass can control the class which gets u
I have a small class hierachy and I want all the objects to have a pointer to any other object from this class hierachy. So I decided a static vector of shared_ptr a good idea. More specifically, I have a class A which has a protected field: static s
The title is pretty much self explanatory, but I think this is better explained with an example. class Dog(): def __init__(self, name): self.name = name def get_name(self): return self.name def get_color(self): return body_color() class personality_1
The following code in java, when run on elipse, gives same output even if we replace superclass s=new sub(); with, sub s= new sub(); Note that we have overridden methods. Output is: changed supermethod in sub class num is sub class 5 Code: public cla
I have a base class in an OpenGL project which represents 3DModel in general. Now I want to create a more specialized class that will inherits from 3DModel. My problem is the mandatory base class constructor call in the initialization list. Is there
We are supposed to make classes of animals which inherit from classes of different types of animals, i.e the Dog class will inherit from the Carnivore class which will inherit from the Mammal class. I have tried using my classes in my own main functi
So say I have 3 classes: Base, A, and B. Base is a base class for both class A and class B. Base has a variable val that A and B can access. How would I get it to work where I can set the val variable through class A, and it is reflected in class B?
Situation: I have an abstract class with several methods: I have a few sub classes that extend the class above I have a collection <MyAbstractClass> collection filled with new objects of the sub classes in my main class I have a unique method of one
I´m new to c++. i´m getting an error "Symbol 'List' could not be resolved" I´m working on eclipse i can´t figure out what is the problem... List.h here is the declaration of the father class which is a generic class, which Vector will inherit #i
I am having some trouble with writing classes in Arduino. Here is a class called "Jerry." It contains three instances of user-defined classes called Mouth, Move, and Injection. The Arduino IDE complains 'Mouth' does not name a type, and 'Move' d
I have a class A which has become too long. So I have decided to move some of its functions to class B. I have made B inherit from A. Now there are functions in A, which need functions in B. My question is where should I instantiate class B in class
I am trying to use the Singleton design pattern via my abstract Charcter class so all sub classes can acces the object instance. Here is my singleton class: class GatewayAccess { private static GatewayAccess ph; // Constructor is 'protected' protecte
Does anyone know why covariant return types are not supported in C#? Even when attempting to use an interface, the compiler complains that it is not allowed. See the following example. class Order { private Guid? _id; private String _productName; pri
I have the following: class A{ @XmlElement String name; //getters and setters } and class B extends A{ @XmlElement String height; //getters and setters } finally I have @XmlRootElement class P{ @XmlElement List<A> things; //getters and setters } If
This is a follow up question on the following answer : Parent Object in php class A { protected function doSomeStuff(){ echo 'a method that all children will need to call'; } } class B { protected $_parent; public function __construct($parent) { $thi
I was not really sure how to formulate my question, but here is the puzzle I am trying to resolve: if (config.a) myObject = new Object<DummyInterface>(); else myObject = new Object<RealInterface>(); so the task is to create a object with a dum
Is there any technical difference between a class which inherits from another class and a class which is a subclass of it? What's the difference between A and B in the following code: A) public class foo { ... private class bar {...} } B) public clas
It is clear that the T[] array type is not covariant as the elements of a T[] can be set by index. And yet, a U[] can be cast to a T[] without any complaints from the compiler as long as U derives from T. Man[] men = new[] { new Man("Aaron"), ne
I'm slightly confused about runtime polymorphism. Correct me if I am wrong, but to my knowledge, runtime polymorphism means that function definitions will get resolved at runtime. Take this example: class a { a(); ~a(); void baseclass(); } class b: c
One way to hack limited form of polymorphism in C is to do something like this: typedef struct { int x; } base; typedef struct { base super; int y; } derived; Now you can refer to a derived instance as a base instance, depending on how the variable i
I have a class that extends a class that I need to overide, but I need to call that class's parent class. since I can't call super since that will execute the direct parent what is the best way to get the parent of my parent class? I am sure this is
We just started learning about class inheritance and attribute lookup in python. I have a question about the following code: class a : n = 1 class b : n = 2 class c : n = 3 class d (a,b) : pass class e (d,c) : pass I know that e.n would equal 1 due t
EDIT: I simplified the problem to leave only what really bothers me. Hello all, I am trying to make the following mapping. In my database, I have a table called "ReportRowValue" containg the following columns: RowNumber ColumnNumber StringValue
