Homework SourseFind any Java Fraction class on the Internet Add any methods
Find any Java Fraction class on the Internet. Add any methods from the Lecture slides that are not implemented. Add a static “main” method that tests every single method, including constructors, for correctness.
Here\'s what I have so far:
public class Fraction { public static final Fraction ZERO = new Fraction(); //constants
private int numerator, denominator; //instance variables
public Fraction() { numerator=0; denominator=1;} //default constructor
public Fraction(int num, int denom) {numerator = num; denominator = denom;}
public Fraction(Fraction toCopy) { //copy constructor
this.numerator = toCopy.numerator; /* … */}
public Fraction(String constant) {return Fraction.parse(constant); } /*optional*/
public int getNumerator() {return numerator;} //getter or accessor
public Fraction set(int num, int denom) //setter
{numerator = num; denominator = denom; return this;}
public Fraction reduce() { /* … */ return this;} //mutator
public Fraction add(Fraction f) { /* … */ return this;} //mutator
public int compareTo(Fraction f) { /* … */ return 0;} //predicate or test
public boolean equals(Object o) { /* … */ return true; } //predicate or tests
public static Fraction parse(String input) { /* … */ return ZERO;} //converts toString output
public String toString() { /* … */ return “3/4”;} //enables System.out.print }
Those were all the method from the lecture slide plus any others I could find. I just need them tested in a main method now and I\'m not sure how to do that.
Solution
Hi, Please find my implementation.
Please let me know in case of any issue.
############## Fraction.java ##########
public class Fraction {
/**
* instance variable
*/
public int numerator;
/**
* instance variable
*/
public int denominator;
// copy constructor
public Fraction(Fraction other) {
numerator = other.numerator;
denominator = other.denominator;
}
/**
* param n
* param d
*/
public Fraction(int n, int d) {
if(d == 0){
System.out.println(\"Denominator can not be negative\");
System.exit(0);
}
// finding gcd of n and d
int gcd = reduce(n, d);
// storing numerator and denominator in reduced form
numerator = n/gcd;
denominator = d/gcd;
}
// toString method
public String toString(){
return numerator+\"/\"+denominator;
}
// equal method
public boolean equals(Object other)
{
if( other != null && ! (other instanceof Fraction ) ) return false;
Fraction that = (Fraction)other;
if(numerator == that.numerator && denominator == that.denominator)
return true;
else
return false;
}
/**
* function to calculate gcd of numerator and denominator
*/
private int reduce(int numerator, int denominator) {
int min = numerator;
int gcd;
if (numerator > denominator) {
min = denominator;
}
for (gcd = min; gcd > 1; gcd--) {
if (numerator % gcd == 0 && denominator % gcd == 0) {
break;
}
}
return gcd;
}
public Fraction add(Fraction other){
int num = numerator*other.denominator + denominator*other.numerator;
int deno = numerator*denominator;
int gcd = reduce(num, deno);
return new Fraction(num/gcd, deno/gcd);
}
public Fraction set(int num, int denom) //setter
{numerator = num; denominator = denom; return this;}
public int compareTo(Fraction f) {
double f1 = (double)numerator/(double)denominator;
double f2 = (double)f.numerator/(double)f.denominator;
if(f1 < f2)
return -1;
else if(f1 > f2)
return 1;
else
return 0;
} //predicate or test
}
############## FractionTest.java ################
public class FractionDriver {
public static void main(String[] args) {
Fraction a = new Fraction(1,2);
Fraction b = new Fraction(3,4);
Fraction c = new Fraction(b);
System.out.println(\"a:\"+a.toString());
System.out.println(\"b:\"+b.toString());
System.out.println(\"c:\"+c.toString());
a.add(b);
a = a.add(b);
System.out.println(\"a:\"+a.toString());
System.out.println(\"b:\"+b.toString());
System.out.println(\"c:\"+c.toString());
System.out.println(\"a.equals(b):\" + a.equals(b));
System.out.println(\"b.equals(c):\" + b.equals(c));
}
}
/*
Sample output:
a:1/2
b:3/4
c:3/4
a:5/1
b:3/4
c:3/4
a.equals(b):false
b.equals(c):true
*/
