In this program, we will implement method overloading based on the different number of arguments but here we will demonstrate type promotion, here we will pass argument float type, but argument is defined of type double in the method signature.

Program/Source Code:

The source code to implement method overloading based on type promotion is given below. The given program is compiled and executed successfully.

// Java program to implement method overloading 
// based on type promotion

public class Main {
  static double sum(int num1, int num2) {
    double s = 0;
    s = num1 + num2;
    return s;
  }
  
  static double sum(int num1, double num2) {
    double s = 0;
    s = num1 + num2;
    return s;
  }

  public static void main(String[] args) {
    double result = 0;

    result = sum(10, 20);
    System.out.println("Sum : " + result);

    result = sum(20, 20.56F);
    System.out.println("Sum : " + result);
  }
}

Output:

Sum : 30.0
Sum : 40.55999946594238

Explanation:

In the above program, we created a Main class that contains a method main() and 2 overloaded method sum() to calculate the addition of specified arguments.

The main() method is the entry point for the program, here we passed the argument float type, but the argument is defined as type double in method signature using the below statement,

result = sum(20, 20.56F);