      1  import java.io.Serializable;

      2

      3  /**

      4     A bank account has a balance that can be changed by

      5     deposits and withdrawals.

      6  */

      7  public class BankAccount implements Serializable

      8  {

      9     private int accountNumber;

     10     private double balance;

     11

     12     /**

     13        Constructs a bank account with a zero balance.

     14        @param anAccountNumber the account number for this account

     15     */

     16     public BankAccount(int anAccountNumber)

     17     {

     18        accountNumber = anAccountNumber;

     19        balance = 0;

     20     }

     21

     22     /**

     23        Constructs a bank account with a given balance.

     24        @param anAccountNumber the account number for this account

     25        @param initialBalance the initial balance

     26     */

     27     public BankAccount(int anAccountNumber, double initialBalance)

     28     {

     29        accountNumber = anAccountNumber;

     30        balance = initialBalance;

     31     }

     32

     33     /**

     34        Gets the account number of this bank account.

     35        @return the account number

     36     */

     37     public int getAccountNumber()

     38     {

     39        return accountNumber;

     40     }

     41

     42     /**

     43        Deposits money into the bank account.

     44        @param amount the amount to deposit

     45     */

     46     public void deposit(double amount)

     47     {

     48        double newBalance = balance + amount;

     49        balance = newBalance;

     50     }

     51

     52     /**

     53        Withdraws money from the bank account.

     54        @param amount the amount to withdraw

     55     */

     56     public void withdraw(double amount)

     57     {

     58        double newBalance = balance - amount;

     59        balance = newBalance;

     60     }

     61

     62     /**

     63        Gets the current balance of the bank account.

     64        @return the current balance

     65     */

     66     public double getBalance()

     67     {

     68        return balance;

     69     }

     70  }