Jackson processes @JsonTypeInfo before choosing which Deserializer to use, probably because the choice of Deserializer could depend generally on the type. However, you can easily disable this on a per-field basis the same way you specify custom Deserializer – by annotating the field directly: @JsonDeserialize(using = DefinitionDeserializer.class) @JsonTypeInfo(use = JsonTypeInfo.Id.NONE) private Definition definition;
Depends on compiler. In VC++, the vtable pointer stored at the beginning of the object allocation, before any member data. (Provided your class has at least one virtual member function.) There also may be multiple vtable pointers, if your class multiply-inherits from other classes with vtables. The vtables themselves are statically allocated somewhere in your … Read more
By the time your destructor is called, the destructor of inherited classes has already been called. Within constructors and destructors, the dynamic type of the object can effectively be considered to be the same as the static type. That is, when you call virtual methods from within your constructors/destructors it’s not the overriden versions of … Read more
Polymorphism can be achieved through overriding. Put in short words, polymorphism refers to the ability of an object to provide different behaviors (use different implementations) depending on its own nature. Specifically, depending on its position in the class hierarchy. Method Overriding is when a method defined in a superclass or interface is re-defined by one … Read more
Inheritance clearly means a knowledge of the base class. @staticmethod is ignorant of the class it is ‘attached’ to(hence they earlier-not now-a-days-called it ‘unbound;’ now technically @staticmethod is not a method at all; it is a function. But @classmethod is fully aware of the class it is attached to; it is technically not a function, … Read more
Idiomatic Clojure favors defining independent functions that operate on a very small set of core data structures; this unbundling of methods and data is a strong statement against object orientation and in favour of a functional style. Rich Hickey (creator of Clojure) has repeatedly stated the importance of this; for example here: “Clojure eschews the … Read more
As said, JavaScript is a dynamic typed language based on prototypal inheritance, so you can’t really use the same approach of typed languages. A JS version of what you wrote, could be: function Shape(){ throw new Error(“Abstract class”) } Shape.prototype.printSurface = function () { throw new Error (“Not implemented”); } function Rect() { // constructor; … Read more
You could declare, and implement, a pure virtual destructor: class ShapeF { public: virtual ~ShapeF() = 0; … }; ShapeF::~ShapeF() {} It’s a tiny step from what you already have, and will prevent ShapeF from being instantiated directly. The derived classes won’t need to change.
Your example is dynamic binding, because at run time it is determined what the type of a is, and the appropriate method is called. Now assume you have the following two methods as well: public static void callEat(Animal animal) { System.out.println(“Animal is eating”); } public static void callEat(Dog dog) { System.out.println(“Dog is eating”); } Even … Read more
That was one of my first questions in Stack Overflow or about Scala. The problem is that Scala maintains compatibility with Java, and that means its basic numeric types are equivalent to Java’s primitives. The problem arises in that Java primitives are not classes, and, therefore, do not have a class hierarchy which would allow … Read more