How do you write a distance formula in java?

How do you write a java program to solve the distance between two points in java?More specificly, give an example program please!

How do you write a distance formula in java?
double distance(double x1, double y1, double x2, double y2)


{


return math.sqrt((x1-x2)(x1-x2) + (y1-y2)(y1-y2));


}