public class TestBankAccount { public static void main(String[] args) { Account a; BankAccount b; CheckingAccount c; SavingAccount s; s = new SavingAccount(); System.out.println(); c = new CheckingAccount(); System.out.println(); System.out.println("s.getMonthlyFees():"); s.getMonthlyFees(); System.out.println(); b = s; System.out.println("b.getMonthlyFees():"); b.getMonthlyFees(); System.out.println(); System.out.println("b.setBalance(10000):"); b.setBalance(10000); System.out.println("b.getMonthlyFees():"); b.getMonthlyFees(); System.out.println(); System.out.println("c.getMonthlyFees():"); c.getMonthlyFees(); System.out.println(); a = b; // a.getMonthlyFees(); } }