Demonstration of adhoc polymorphism via function overloading

AdHocPolymorphism.java

public class AdHocPolymorphism {

    // ad hoc polymorphism to refers to
    // polymorphic functions which can be
    // applied to arguments of different types,

    public static class Adder {

        // Note: int[] is not coercible to double[]

        public static int add(int[] integers) {
            int sum = 0;
            for(int i = 0 ; i < integers.length ; ++i) {
                sum += integers[i];
            }
            return sum;
        }

        public static double add(double[] doubles) {
            double sum = 0.0;
            for(int i = 0 ; i < doubles.length ; ++i) {
                sum += doubles[i];
            }
            return sum;
        }

    }

    // the add functions seems to work generically
    // over various types when looking at the
    // invocations, but are considered to be two
    // distinct functions by the compiler.

    public static class TestAdder {

        public static void main(String[] args) {
            int[] integers = {1, 2, 3, 4, 5};
            System.out.println (
                Adder.add(integers)
            );

            double[] doubles = {1d, 2d, 3d, 4d, 5d};
            System.out.println (
                Adder.add(doubles)
            );

            // won't compile
            float[] floats = {1f, 2f, 3f, 4f, 5f};
            System.out.println (
                Adder.add(floats)
            );

        }

    }

}