Chapter 13, Problem 13.14PE

(Demonstrate the benefits of encapsulation) Rewrite the Rational class in Listing 13.13 using a new internal representation for the numerator and denominator. Create an array of two integers as follows:

private long[] r = new long[2];

Use r[0] to represent the numerator and r[1] to represent the denominator. The signatures of the methods in the Rational class are not changed, so a client application that uses the previous Rational class can continue to use this new Rational class without being recompiled.