Question

1. Add another public method called add to your Fraction class. This method adds another fraction to the ‘calling object’. Thus, the method will take a Fraction class object as a parameter, add this parameter fraction to the calling object (fraction), and return a Fraction object as a result. HINT: We can use cross multiplication to determine the numerator of the resultant Fraction. The denominator of the resultant Fraction is simply the multiplication of the denominators of the two other Fractions.

   
   

2. Add a private method simplify() to your Fraction class that converts a fraction to its simplest form. For example, the fraction 20 / 60 should be stored in the class instance variables as 1 / 3 (i.e. numerator = 1, denominator = 3). N.B. you will need a method to determine the Greatest Common Divisor (GCD). Remember, both of these methods (simplify and gcd) must be private. As these methods are private, client programs cannot access them. So, how are they to be used? Given their purpose, it would mean that any Fraction class method that modifies the instance variables (e.g.: add, ICT167 Principles of Computer Science 2 constructor, set) should call the simplify() method to reduce the instance variables to their minimum values. Thus, these methods are used only for housekeeping; they are not to be used by client programs. Make sure you understand how the following GCD algorithm work before implementing it.

                        // function gcd; two integer parameters

                           int gcd(int n1, int n2)

                                // local variable c

                                int c

                               loop while ( n1 != 0 AND n2 != 0 )

                               c = n2

                               n2 = n1 % n2 // modulus operator

                               n1 = c

                          return (n1 + n2)

   
   

3. Write a client class (TestFraction2) that allows the user to add up any number of non-zero fractions. The program should display the running total as an exact fraction (in simplified form as numerator / denominator). The user can finish by entering a fraction that represents a zero fraction. Note: If you need any implement any more methods (private or public) in the class to complete this question, you will need to justify and explain it clearly here.

   
   

   
   

4. import java.util.Scanner;
   
   public class Fraction 
   {
       private int numerator;
       private int denominator;
       public void inputValues()
       {
           System.out.println("Enter any 2 numbers for a fraction.");
           Scanner input = new Scanner(System.in);
           numerator = input.nextInt();
           denominator = input.nextInt();
       }
       
       public void outputValues()
       {
           System.out.println("The fraction is " + numerator + "/" + denominator + ":");
       }
       public int getNumerator()
       {
           return numerator;
       }
       public int getDenominator()
       {
           return denominator;
       }
   }

5. import java.util.Scanner;
   
   /* import Fraction.java into this class and
   use while loop to continue asking the user to enter
   a fraction and if the user enter a negative input
   the loop will end
   */
   
   
   public class TestFraction 
   {
       public static void main(String[] args)
       {
           Scanner kboard = new Scanner(System.in);
           Fraction fTotal = new Fraction(); 
           fTotal.setNumerator(0); // Zero fraction number
           fTotal.setDenominator(1);
           Fraction fNumber = new Fraction();
           while (true)
           {
               System.out.println("Enter numerator: ");
               int numerator = kboard.nextInt();
               if (numerator == 0)
               {
                   break; // Zero fraction, stop the loop
               }
               System.out.println("Enter denominator: ");
               int denominator = kboard.nextInt();
               fNumber.setNumerator(numerator);
               fNumber.setDenominator(denominator);
               fTotal = fTotal.add(fNumber);
               System.out.println(fTotal.toString());
           }
       }
   }

Answer 1

1. 

TestFraction.java:

import java.util.Scanner;
public class TestFraction {
public static void main(String arg[]) {
Scanner in = new Scanner(System.in);
int numerator, denominator;
while (true) {
System.out.print("Enter a numerator : ");
numerator = in.nextInt();
if (numerator >= 0) {
System.out.print("Enter a denominator : ");
denominator = in.nextInt();
Fraction f = new Fraction(numerator, denominator);
System.out.println("Your fraction is: " + f);
System.out.println("---------------------");
System.out.println("Enter another number to compare");
System.out.print("Enter numerator: ");
int cpNumerator = in.nextInt();
System.out.print("Enter denomainator: ");
int cpDenominator = in.nextInt();
Fraction f1 = new Fraction(cpNumerator, cpDenominator);
if (f.isEquals(f1)) {
System.out.println("Both fractions " + f1 + " and " + f + " are equal\n");
} else {
System.out.println("Both fractions " + f1 + " and " + f + " are not equal\n");
}
} else {
System.out.println("exiting");
System.exit(0);
}
}
}
}