java final methods vs c++ nonvirtual functions

are java final methods and c++ nonvirtual methods different or the same? How?

You can still declare non-virtual member functions with the same signature in inheriting classes in C++, where-as Java explicitly forbids declaring methods with the same signature in which the base class declares that method final. Virtuality in C++ just helps find the correct function to call when dealing with inheritance/polymorphism.

Example:

#include <iostream>

class Base
{
public:
    void doIt()
    {
        std::cout << "from Base.doIt()" << std::endl;
    }
};

class Child : public Base
{
public:

    void doIt()
    {
        std::cout << "from Child.doIt()" << std::endl;
    }
};

int main()
{
    Base a;
    a.doIt(); // calls Base.doIt()
    Child b;
    b.doIt(); // calls Child.doIt()
    Base *c = new Base();
    c->doIt(); // calls Base.doIt()
    Child *d = new Child();
    d->doIt(); // calls Child.doIt()
    Base *e = new Child();
    e->doIt(); // calls Base.doIt()
    std::cin.ignore();
    return 0;
}

The comparable example in Java using final will result in a compiler error:

public class Base
{
    public final void doIt()
    {
        System.out.println("In Base.doIt()");
    }
}

public class Child extends Base
{
    public void doIt() // compiler error: Cannot overload the final method from Base
    {
        System.out.println("In Child.doIt()");
    }
}

For more explanation on Polymorphism in C++, see cplusplus.com: Polymorphism

Effictively, though, both methods have similar goals: to prevent overriding of a function in the base class. They just go about it in slightly different ways.