/**
 * Created by hajarboulhdir on 02/10/2016.
 */
public class Sphere extends Shape3D{
    private double radius;
    public double volume(){
        return( 4.0 / 3.0 ) * Math.PI * Math.pow( this.radius, 3.0 );

    }

    @Override
    public double surface() {
        return 0;
    }

    @Override
    public Point3D getRefPoint() {
        return null;
    }
}

@@ -107,16 +107,138 @@
  radius;
+%0A%0A    public Sphere() %7B%0A        this(0.0);%0A    %7D%0A%0A    public Sphere(double radius) %7B%0A        this.radius = radius;%0A    %7D%0A%0A
 %0A    pub
@@ -328,17 +328,16 @@
  3.0 );%0A
-%0A
     %7D%0A%0A 
@@ -449,24 +449,24 @@
 efPoint() %7B%0A
-
         retu
@@ -479,11 +479,73 @@
 l;%0A    %7D
+%0A%0A    public double getRadius() %7B%0A        return radius;%0A    %7D
 %0A%7D%0A

Add Sphere class.