dynamic-binding

问题 I had initial apprehensions about posting this question lest it be a duplicate.But even after googling with many keywords,I couldn't find any link on StackOverflow that explains static and dynamic binding for C.There are questions and answers for C++ though,but all involve classes and stuff that are clearly not for C.And the links outside StackExchange were quite dubious. I need to know the rigorous definition and contrast between these two bindings,exclusively in the context of C.I would

问题 I had initial apprehensions about posting this question lest it be a duplicate.But even after googling with many keywords,I couldn't find any link on StackOverflow that explains static and dynamic binding for C.There are questions and answers for C++ though,but all involve classes and stuff that are clearly not for C.And the links outside StackExchange were quite dubious. I need to know the rigorous definition and contrast between these two bindings,exclusively in the context of C.I would

问题 I have N Servers, N DBs and N configuration. see the scenario below So, on every request , I need to access server and db based on configuration. How can implement dynamically data source in spring data jpa? 回答1: You can try AbstractRoutingDatasource provided by Spring since version 2.0.1. using which you can dynamically use appropriate data-source . For integration with Spring data JPA check this very good example. In your case since your configurations are in DB instead of properties file

问题 So I am having some confusion understanding dynamic binding vs upcasting. My original understanding was that when you create a base_class reference and assign it to a derived class object like: base_class obj = new derived_class(); you can now call the methods/member functions of derived_class with obj.method_of_derived class() , without dynamic binding. I thought you only needed dynamic binding when the base_class and derived_class have functions/methods that have the same name, and some

问题 I am using jquery file upload function on my page like following: $('.new-variant-image') .fileupload({ dataType: 'script', add: function(e, data){ } }); but the DOM class "new-variant-image" is dynamically created after the page is loaded, so it wouldn't work. I searched ways to bind dynamic event using "on" and "live" but wouldn't get it to work in this case. Any assistance will be much thanked. Edit The DOM element "new-variant-image" is created afterwards using AJAX, it works if I put the

问题 When i invoke a virtual function from a base constructor, the compiler does not give any error. But when i invoke a pure-virtual function from the base class constructor, it gives compilation error. Consider the sample program below: #include <iostream> using namespace std; class base { public: void virtual virtualfunc() = 0; //void virtual virtualfunc(); base() { virtualfunc(); } }; void base::virtualfunc() { cout << " pvf in base class\n"; } class derived : public base { public: void

问题 I have a problem in virtual function: Here is some code as an example: class A { public : virtual void print(void) { cout<< "A::print()"<<endl; } }; class B : public A { public : virtual void print(void) { cout<<"B::print()"<<endl; } }; class C : public A { public : void print(void) { cout<<"C::print()"<<endl; } }; int main(void) { A a,*pa,*pb,*pc; B b; C c; pa=&a; pb=&b; pc=&c; pa->print(); pb->print(); pc->print(); a=b; a.print(); return 0; } the result: A::print() B::print() C::print() A:

问题 When I was trying the Animal/Food example for abstract types in Martin Odersky's Programming in Scala , class Food abstract class Animal { type SuitableFood <: Food def eat(food:SuitableFood) } class Grass extends Food class Cow extends Animal { type SuitableFood=Grass override def eat(food:SuitableFood) {} } val bessy:Animal = new Cow bessy.eat(new Grass) I got the following error: scala> <console>:13: error: type mismatch; found : Grass required: bessy.SuitableFood bessy.eat(new Grass) ^

问题 I'm not sure how to do this... function f1() { var x = 10; function f2(fx) { var x; x = 6; fx(); }; function f3() { print x; }; f2(f3); }; For each of the following two binding methods, what would the program print? A) Shallow Binding B) Deep Binding Thanks for the help! 回答1: Deep/shallow binding makes sense only when a procedure can be passed as an argument to a function. Deep binding binds the environment at the time a procedure is passed as an argument. Shallow binding binds the

问题 While at their core dynamic binding and templates are fundamentally different things, they can be used to implement the same functionality. Code example (only for reference) A) dynamic binding namespace DB { // interface class CustomCode { public: virtual void operator()(char) const = 0; }; class Lib { public: void feature(CustomCode const& c) { c('d'); } }; // user code class MyCode1 : public CustomCode { public: void operator()(char i) const { std::cout << "1: " << i << std::endl; } };