How to create & implement interface in java.

 

Create interface Test

package Program;
/**
 *
 * @author Dilip
 */
public interface Test {
    public void sum(int a,int b);
    public void sum(double x,double y);
}

Create class Testinterface

package Program;
/**
 *
 * @author Dilip
 */
public class Testinterface implements Test {
    int ia,ib;
    double dx,dy;
    public void sum(int a, int b) {
       int c;
        ia=a;
       ib=b;
       c=ia+ib;
       System.out.println("Addition of int number="+c);
    }
    public void sum(double x, double y) {
        double z;
        dx=x;
        dy=y;
        z=dx+dy;
        System.out.println("Addition of double number="+z);
}
    public static void main(String args[])
    {
        Testinterface obj=new Testinterface();
        obj.sum(10,20);
        obj.sum(10.1,20.3);
    }
}

Output:

Addition of int number=30
Addition of double number=30.4