account.java

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//********************************************************************
//  Account.java       Author: Lewis/Loftus
//
//  Represents a bank account with basic services such as deposit
//  and withdraw.
//********************************************************************

import java.text.NumberFormat;

public class Account
{
   private NumberFormat fmt = NumberFormat.getCurrencyInstance();

   private final double RATE = 0.035;  // interest rate of 3.5%

   private long acctNumber;
   private double balance;
   private String name;

   //-----------------------------------------------------------------
   //  Sets up the account by defining its owner, account number,
   //  and initial balance.
   //-----------------------------------------------------------------
   public Account (String owner, long account, double initial)
   {
      name = owner;
      acctNumber = account;
      balance = initial;
   }

   //-----------------------------------------------------------------
   //  Validates the transaction, then deposits the specified amount
   //  into the account. Returns the new balance.
   //-----------------------------------------------------------------
   public double deposit (double amount)
   {
      if (amount < 0)  // deposit value is negative
      {
         System.out.println ();
         System.out.println ("Error: Deposit amount is invalid.");
         System.out.println (acctNumber + "  " + fmt.format(amount));
      }
      else
         balance = balance + amount;

      return balance;
   }

   //-----------------------------------------------------------------
   //  Validates the transaction, then withdraws the specified amount
   //  from the account. Returns the new balance.
   //-----------------------------------------------------------------
   public double withdraw (double amount, double fee)
   {
      amount += fee;

      if (amount < 0)  // withdraw value is negative
      {
         System.out.println ();
         System.out.println ("Error: Withdraw amount is invalid.");
         System.out.println ("Account: " + acctNumber);
         System.out.println ("Requested: " + fmt.format(amount));
      }
      else
         if (amount > balance)  // withdraw value exceeds balance
         {
            System.out.println ();
            System.out.println ("Error: Insufficient funds.");
            System.out.println ("Account: " + acctNumber);
            System.out.println ("Requested: " + fmt.format(amount));
            System.out.println ("Available: " + fmt.format(balance));
         }
         else
            balance = balance - amount;

      return balance;
   }

   //-----------------------------------------------------------------
   //  Adds interest to the account and returns the new balance.
   //-----------------------------------------------------------------
   public double addInterest ()
   {
      balance += (balance * RATE);
      return balance;
   }

   //-----------------------------------------------------------------
   //  Returns the current balance of the account.
   //-----------------------------------------------------------------
   public double getBalance ()
   {
      return balance;
   }

   //-----------------------------------------------------------------
   //  Returns the account number.
   //-----------------------------------------------------------------
   public long getAccountNumber ()
   {
      return acctNumber;
   }

   //-----------------------------------------------------------------
   //  Returns a one-line description of the account as a string.
   //-----------------------------------------------------------------
   public String toString ()
   {
      return (acctNumber + "\t" + name + "\t" + fmt.format(balance));
   }
}