Rational class for java can't run program

Question

So we have to create a Rational class that does the following. Create a project in Java that includes a Rational class. The class represents Rational numbers. It should have only 2 fields num and denom. It should have the following public methods (and any other private methods needed):

• A constructor that takes a num and denom (in that order) as initial field values. If denom is 0, set the number to 0/1.
• An accessor for num (getNum)
• An accessor for denom (getDenom)
• A toString method that returns String of the form "num/denom" (no spaces) where num and denom have the stored values
• An add method that takes a Rational number r and returns a Rational number that is the result of adding r to this Rational number. It should not change this rational number.
• (Extra credit - 2 points) A reduce method with no arguments that reduces this Rational number to lowest form.

I have code that I have done in Intellij IDEA but it will not let me run the program. I know that I am getting errors for most things but I believe it is just because I am not putting something in the correct place or leaving something out. This is what I have so far.

import java.util.Scanner;

public class Rational {

    private int num;
    private int den; //fields

    static Scanner userInput = new Scanner(System.in);

    public static void main(String[] args) {

        System.out.println("")

        public Rational( int n, int d){

            num = n;
            den = d;

            if (d == 0) {
                num = 0;
                den = 1;

                System.out.println("Denominator is 0. Enter a number other than 0 next time.");

            }//close if

            int g = gcd(num, den);
            num = n / g;
            den = d / g;

        }//close Rational

    public String toString() {

        if (den == 1) {
            return num + "";

        } else {

            return num + "/" + den;

        }

    }//close toString

    private Rational add(Rational r) {

        int newNum = (this.num * r.den) + (r.num * this.den);
        int newDen = r.den * this.den;
        return new Rational(newNum, newDen);

    }//close add

    private static int gcd(int m, int n) {

        if (0 == n) {
            return m;

        } else {

            return gcd(n, m % n);

        }//close else

    }//close gcd

}//close main

}//close class

Answer 1

      public Rational(int n, int d){ // put Your Constructor Out of the main First
         num = n;
         den = d;

         if (d == 0) {
            num = 0;
            den = 1;
            System.out.println("Denominator is 0. Enter a number other than 0 next time.");
        }//close if
         int g = gcd(num, den);
         num = n / g;
         den = d / g; 
       }//close Rational
    }

  public String toString() {  //put methods Outside of Main
                if (den == 1) {
                    return num + "";
                } else {

                    return num + "/" + den;

                }

            }//close toString

     private Rational add(Rational r) {   //put methods Outside of Main

          int newNum = (this.num * r.den) + (r.num * this.den);
          int newDen = r.den * this.den;
          return new Rational(newNum, newDen);
     }//close add

    private static int gcd(int m, int n) {  //put methods Outside of Main
                if (0 == n)
                    return m;
                else
                    return gcd(n, m % n);        
            }//close gcd

    public static void main (String [] args) { //here is your Main Method.

            System.out.println("");

            // call Your Methods Accordingly. 

        } // main Closed
    } //class Closed

1. You have put Constructor into the main Method. It should be out of the main box.
2. Each method that you Defined is exists within the main Method. Again a Compilation Error .
3. You can call these methods From inside of main either using any class object (If Instance method) or using Class Name directly (If Static Method).