java - Calculating the distance between 2 Points in 2D and 3D -

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i'm trying solve simple problem, have minor isses. hope can out beginner real quick ;)

i have 2 classes 'point' , 'point3d' that:

public class point {     protected double x;     protected double y;      point(double xcoord, double ycoord){         this.x = xcoord;         this.y = ycoord;     }      public double getx(){         return x;     }      public double gety(){         return y;     }      public static double distance(point a, point b)     {         double dx = a.x - b.x;         double dy = a.y - b.y;         return math.sqrt(dx * dx + dy * dy);     }      public static void main(string[] args) {         point p1 = new point(2,2);         point p2 = new point(5,6);         system.out.println("distance between them " + point.distance(p1, p2));     } }

and this:

public class point3d extends point {     protected double z;      point3d(double x, double y, double zcoord){         super(x, y);         this.z = zcoord;     }      public double getz(){         return z;     }      public static double distance(point p1, point p2){         double dx = p1.x - p2.x;         double dy = p1.y - p2.y;         double dz = p1.z - p2.z;         return math.sqrt(dx * dx + dy * dy + dz *dz);     }      public static void main(string[] args) {         point3d p1 = new point3d(-4,2,5);         point3d p2 = new point3d(1,3,-2);         system.out.println("distance between them " + point3d.distance(p1, p2));     } }

my problem following: if keep code this, eclipse saying 'z cannot resolved field' , possible solution should create in class 'point'. after doing class 'point3d' compiles doesn't calculate right answer..

greetings,

change signature of point3d distance method to:

public static double distance(point3d p1, point3d p2){

you had point types arguments, don't have z.


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