Using the Super Word in a tutorial

Question

ive created two classes:
public class Polygon
int sides;
double area;
public Polygon()
System.out.println("Inside no-arg constructor");
public String NumberOfSides()
System.out.println("The Number of Sides = " + sides);
return sides;
public String toString()
System.out.println("Inside Polygon toString")
String rep = "Sides" + sides + "area" + area;
return rep;
public Polygon(int s)
sides = s;
System.out.println("Inside One-Arg Constructor");
public class Triangle extends Polygon
int base;
int height;
public Triangle(int b, int h)
base = b;
height = h;
The tutorial i am using says, 'Add a constructor to Triangle that takes in two int's for base and height. The constructor needs to use super() to invoke the constructor in Polygon, passing in 3 for the number of sides. Print out the message "Inside Triangle Constructor"
as you can see i've created the triangle constructor which takes in the two int's but i am unsure how to use the super keyword to use the constructor within the polygon class to pass in 3 as the number of sides.
can someone help me in solving this problem.
Thanks
Richard.

Answer 1

if i was to change the order to that would it not
take the NumberOfSides() and the toString() methods
out of the no-argument constructor?You cannot put methods inside methods.
That makes no sense in Java.
i deliberately
put them there because i only want them for the
no-arg constructor. or must methods be seperate
entities from constructors?Yes.
And in fact, you have 2 more problems:
your "sides" and "area" variable are uninitialized
if people use your "no-arg" constructor,
so the compiler will complain.
You need to assign them some value in your constructor
(perhaps "slides=0; area=0;")