Demo of Interfaces in Java
Here we use interfaces to solve quadratic and linear equations.
We have two interfaces EqFace1 and EqFace2 that are implemented in class Equation (methods solve1 and solve2).
import java.lang.Math;
interface EqFace1
{
void solve1(double a, double b);
}
interface EqFace2
{
void solve2(double a, double b, double c);
}
class Equation implements EqFace1, EqFace2
{
public void solve2(double a, double b, double c)
{
System.out.println(a+"x2 + "+ b+"x +" + c + " = 0");
double delta = b*b - 4*a*c;
if(delta >=0)
{
double x1 = (-b - Math.sqrt(delta)) / (2*a);
double x2 = (-b + Math.sqrt(delta)) / (2*a);
System.out.println("x1 =" + x1 + " x2 =" + x2);
}
else
{
System.out.println("No solution");
}
}
public void solve1(double a, double b)
{
System.out.println("x = " + ( -b / a));
}
}
class Main
{
public static void main(String args[]){
Equation e1 = new Equation();
e1.solve1(2, 4);
Equation e2 = new Equation();
e2.solve2(1, 5, 6);
}
}