Section 13.9 Check Point Questions7 questions

13.9.1

Show the output of the following code?

Rational r1 = new Rational(-2, 6);
System.out.println(r1.getNumerator());
System.out.println(r1.getDenominator());
System.out.println(r1.intValue());
System.out.println(r1.doubleValue());

13.9.2

Why is the following code wrong?

Rational r1 = new Rational(-2, 6);
Object r2 = new Rational(1, 45);
System.out.println(r2.compareTo(r1));

13.9.3

Why is the following code wrong?

Object r1 = new Rational(-2, 6);
Rational r2 = new Rational(1, 45);
System.out.println(r2.compareTo(r1));

13.9.4

Simplify the code in lines 82-85 in LiveExample 13.13, Rational.java, using one line of code without using the if statement. Simplify the code in lines 110-115 using a conditional operator.

13.9.5

Trace the program carefully and show the output of the following code.

Rational r1 = new Rational(1, 2);
Rational r2 = new Rational(1, -2);
System.out.println(r1.add(r2));

13.9.6

The preceding question shows a bug in the toString method. Revise the toString() method to fix the error.

13.9.7

What happens if you create a Rational using new Rational(1, 0)? Discuss the appropriate ways for handling this case.