How does default virtual behavior differ in C++ and Java ?

Default virtual behavior of methods is opposite in C++ and Java:

In C++, class member methods are non-virtual by default. They can be made virtual by using virtual keyword. For example, Base::show() is non-virtual in following program and program prints “Base::show() called”.

#include<iostream> 
  
using namespace std; 
  
class Base { 
public:       
  
    // non-virtual by default 
    void show() {   
         cout<<"Base::show() called"; 
    } 
}; 
  
class Derived: public Base { 
public:       
    void show() { 
         cout<<"Derived::show() called"; 
    }       
}; 
  
int main() 
{ 
  Derived d; 
  Base &b = d;    
  b.show();  
  getchar(); 
  return 0; 
} 

Adding virtual before definition of Base::show() makes program print “Derived::show() called”

In Java, methods are virtual by default and can be made non-virtual by using final keyword. For example, in the following java program, show() is by default virtual and the program prints “Derived::show() called”

class Base { 
  
    // virtual by default 
    public void show() { 
       System.out.println("Base::show() called"); 
    } 
} 
  
class Derived extends Base { 
    public void show() { 
       System.out.println("Derived::show() called"); 
    } 
} 
  
public class Main { 
    public static void main(String[] args) { 
        Base b = new Derived();; 
        b.show(); 
    } 
} 

Unlike C++ non-virtual behavior, if we add final before definition of show() in Base , then the above program fails in compilation.

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How does default virtual behavior differ in C++ and Java ?

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