Invoking virtual method in constructor: difference between Java and C++

Question

In Java:

class Base {
    public Base() { System.out.println(\"Base::Base()\"); virt(); }
    void virt()   { System.out.println(\"Base::virt()\"); }
}

clas         


        

Answer 1

Actually I want to know what's the insight behind this design decision

It may be that in Java, every type derives from Object, every Object is some kind of leaf type, and there's a single JVM in which all objects are constructed.

In C++, many types aren't virtual at all. Furthermore in C++, the base class and the subclass can be compiled to machine code separately: so the base class does what it does without whether it's a superclass of something else.