Java:Compile time and run time polymorphism

Question

void sum(int a, int b){};
void sum(float a, float b){};

The above code is an example for compile time polymorphism but If user is entering the value of a and b, then method call will be determeined at compile time or run time ?

Answer 1

It will be determined at compile-time !!!

The method to be invoked will be determined depending on the reference type of the variables and not the actual value.

Answer 2

Your example would be determined at compile time . Example of runtime polymorphism.

Class A{
   void sum(int a, int b){};
}

Class B extends A{
   @Override
   void sum(int a, int b){};
}

Class C{
  A b = new B();
  b.sum(1, 2);  //whose sum() would be called (A/B)? Decision will take at run time. Runtime polymorphism.
}

Answer 3

Not very clear for your situation but when user has to enter value then too the code will decide which one to call.

public class Sample
{

    void sum(int a, int b)
    {
        System.out.print(a+b);
    }
    void sum(float a, float b){System.out.print(a+b);}
    public static void main(String[] a)
    {
        int a,b;
        float c,d;
        // logic for setting abcd;
        sum(a,b) //sum with int args will be called
        sum(c,d) //sum with float will be called
    }
}

And this will be resolved at compile time only. Hope this will help