overriding

This is not about "When VTABLE is created?" . Rather, when the VPTR should be initialized? Is it at the beginning/end of the constructor or before/after the constructor? A::A () : i(0), j(0) -->> here ? { -->> here ? //... -->> here ? } The machinery for virtual calls (usually a v-table, but doesn't need to be) is set up during the ctor-initializer , after construction of base subobjects and before construction of members. Section [class.base.init] decrees: Member functions (including virtual member functions, 10.3) can be called for an object under construction. Similarly, an object under

I'm having difficulty trying to override a property declared in a profile-specific application properties file on the classpath with another value declared in an overrides file on the file system. I have an auto-configured Spring-boot application (that is, using @EnableAutoconfiguration ) that has multiple profiles, which I launch using PropertiesLauncher rather than JarLauncher (the reason having to do with deployment constraints - I need to deploy an exploded directory rather than an archive into a read-only filesystem.) Within the root of my application, I have some profile-specific

I am trying to understand the object-oriented concepts in Fortran 2003 standards (or later). I have some knowledge in C++ so I think there are some common ideas between these two languages which can help me understand them better. In C++, the polymorphism is done through class derivation and member function overriding. One defines a "abstract" base class where almost all the virtual functions are defined. Different derived classes contains the actual implementation of them. So other functions just need to program based on the "abstract" class. Then they works for all derived classes. I think

My Parent class is : import java.io.IOException; public class Parent { int x = 0; public int getX() throws IOException{ if(x<=0){ throw new IOException(); } return x; } } I extend this class to write a subclass Child : public class Child1 extends Parent{ public int getX(){ return x+10; } } Notice while overriding the getX method in the Child class , I have removed the throws clause from the method definition .Now it results in an anomalous behavior by the compiler which is expected : new Parent().getX() ; does not compile without enclosing it in a try-catch block , as expected . new Child()

I'm trying to subclass str , but having some difficulties due to its immutability. class DerivedClass(str): def __new__(cls, string): ob = super(DerivedClass, cls).__new__(cls, string) return ob def upper(self): #overridden, new functionality. Return ob of type DerivedClass. Great. caps = super(DerivedClass, self).upper() return DerivedClass(caps + '123') derived = DerivedClass('a') print derived.upper() #'A123' print type(derived.upper()) #<class '__main__.DerivedClass'> print derived.lower() #'a' print type(derived.lower()) #<type 'str'> For inherited methods that don't require any new

Per this answer and this answer , Java static methods aren't virtual and can't be overridden. Intuitively, therefore, this should work (even if in 99% of cases it's dangerous programming): class Foo { public static String frob() { return "Foo"; } } class Bar extends Foo { public static Number frob() { return 123; } } However, in practice this gets you: Foo.java:10: frob() in Bar cannot override frob() in Foo; attempting to use incompatible return type found : java.lang.Number required: java.lang.String public static Number frob() { ^ Naively, it seems like Foo.frob() and Bar.frob() should have

I've been wonder for some time what the best practice is for modifying a plugin created by a WordPress user? For example there are a couple lines of code I want to change within the Contact Form 7 plugin. The function is called function wpcf7_ajax_json_echo() and is located in: wp-content > plugins > contact-form-7 > includes > controller.php Of course I could just change the code right in that file and be done, but then I'm out of luck when I want to update that plugin as my modifications will probably get written over. I know I should be making this happen via my functions.php file, but I'm

I have looked all over the place, and found a lot of info... but nothing works for me and I don't get it :( I know that you are suppose to override the registration controller, like this: class Users::RegistrationsController < Devise::RegistrationsController def after_sign_up_path_for(resource) authors_waiting_path end end Then following the example showed by Tony Amoyal http://www.tonyamoyal.com/2010/07/28/rails-authentication-with-devise-and-cancan-customizing-devise-controllers/ , I am supposed to change my routes to update the access the new controller: devise_for :users, :controllers => {