ABSTRACT CLASSES AND INTERFACES - Introduction to Java Programming: Comprehensive Version - page 523

30 }
31
32

/** Return numerator */

33 public long getNumerator() {

34 return numerator;

35 }
36
37 /** Return denominator */

38 public long getDenominator() {

39 return denominator;

40 }
41
42 /** Add a rational number to this rational */
43 public Rational add(Rational secondRational) {
44 long n = numerator * secondRational.getDenominator() +
45 denominator * secondRational.getNumerator();
46

a
b

c
d

ad + bc

+ =

bd

long d = denominator * secondRational.getDenominator();

47 return new Rational(n, d);

48 }
49
50 /** Subtract a rational number from this rational */
51 public Rational subtract(Rational secondRational) {
52 long n = numerator * secondRational.getDenominator()
53 - denominator * secondRational.getNumerator();
54

a
b

c
d

ad - bc

- =

bd

long d = denominator * secondRational.getDenominator();

55 return new Rational(n, d);

56 }
57
58

/** Multiply a rational number by this rational */

59 public Rational multiply(Rational secondRational) {

a
b

c
d

ac
bd

* =

60 long n = numerator * secondRational.getNumerator();

61 long d = denominator * secondRational.getDenominator();

62 return new Rational(n, d);

63 }
64
65 /** Divide a rational number by this rational */

66 public Rational divide(Rational secondRational) {

a
b

c
d

ad
bc

, =

67 long n = numerator * secondRational.getDenominator();

68 long d = denominator * secondRational.numerator;

69 return new Rational(n, d);

70 }
71
72 @Override
73 public String toString() {

74 if (denominator == 1 )

75 return numerator + "" ;

76 else

77 return numerator + "/" + denominator;

78 }
79
80 @Override // Override the equals method in the Object class
81 public boolean equals(Object other) {

82 if (( this .subtract((Rational)(other))).getNumerator() == 0 )

83 return true ;

84 else

85 return false ;

86 }
87
88 @Override // Implement the abstract intValue method in Number
89

public int intValue() {