// Accounts example -- Lowis & Loftus, 1st edition, page 302.

class SavingsAccount {

   protected int account;
   protected double balance;
   protected double rate;

   public SavingsAccount (int accountNum, double initBalance,
                          double intRate) {
   account = accountNum;
   balance = initBalance;
   rate = intRate;
   }

   public void deposit (double amount) {
      balance += amount;
      System.out.println ("Deposit into account " + account);
      System.out.println ("Amount: " + amount);
      System.out.println ("New balance: " + balance);
      System.out.println();
   }

   public boolean withdrawal (double amount) {
      boolean result = false;
      System.out.println ("Withdrawal from account " + account);
      System.out.println ("Amount: " + amount);
      if (amount > balance)
         System.out.println ("Insufficient funds.");
      else {
         balance -=amount;
         System.out.println ("New balance: " + balance);
         result = true;
      }
      System.out.println();
      return result;
   }

   public void addInterest () {
      balance += balance * rate;
      System.out.println ("Interest added to account " + account);
      System.out.println ("New balance: " + balance);
      System.out.println();
   }
}

class BonusSaver extends SavingsAccount {

   private final int PENALTY = 25;
   private final double BONUS_RATE = 0.03;

   public BonusSaver (int accountNum, double initBalance,
                          double intRate) {
      super (accountNum, initBalance, intRate);
   }

   public boolean withdrawal (double amount) {
      System.out.println ("Penalty incurred: " + PENALTY);
      return super.withdrawal (amount + PENALTY);
   }

   public void addInterest () {
      balance += balance * (rate + BONUS_RATE);
      System.out.println ("Interest added to account " + account);
      System.out.println ("New balance: " + balance);
      System.out.println();
   }
}

class Accounts {

   public static void main (String[] args) {

      SavingsAccount savings = new SavingsAccount 
                                 (4321, 8921.39, 0.02);
      BonusSaver bigSavings = new BonusSaver (6543, 1234.00, 0.02);

      savings.addInterest();
      bigSavings.addInterest();

      savings.deposit (456.09);
      bigSavings.deposit (456.09);

      savings.withdrawal (555.99);
      bigSavings.withdrawal (666.88);
   }
}