package cse1030;


/**
 * A simple abstract class for representing bank accounts. The balance is
 * stored as an integer amount (presumably in cents for a North American
 * bank account).
 * 
 * @author EECS1030Z_2014_15W
 *
 */
public abstract class AbstractBankAccount {

  private long balance;
  
  /**
   * Create a bank account with the given starting balance.
   * 
   * @param balance the starting balance of the account
   */
  protected AbstractBankAccount(long balance) {
    this.balance = balance;
  }
  
  /**
   * Deposit an amount of currency into the account.
   * 
   * <p>
   * Exactly how the balance of the account is affected by the
   * deposit is determined by the subclasses; the default
   * behavior supplied by AbstractBankAccount is to add the
   * deposit amount to the balance.
   * 
   * @param amount the amount of currency to deposit into the account
   * @throws IllegalArgumentException if <code>amount < 0</code>
   */
  public void deposit(long amount) {
    if (amount < 0) {
      throw new IllegalArgumentException("deposit amount:" + amount + " is negative");
    }
    this.balance += amount;
  }
  
  /**
   * Withdraw an amount of currency from the account.
   * 
   * <p>
   * Exactly how the balance of the account is affected by the
   * withdrawal is determined by the subclasses; the default
   * behavior supplied by AbstractBankAccount is to subtract the
   * withdrawal amount from the balance.
   * 
   * @param amount the amount of currency to withdraw from the account
   * @throws IllegalArgumentException if <code>amount < 0</code>
   */
  public void withdraw(long amount) {
    if (amount < 0) {
      throw new IllegalArgumentException("withdraw amount:" + amount + " is negative");
    }
    this.balance -= amount;
  }
  
  /**
   * Return the account balance.
   * 
   * @return the account balance
   */
  public long getBalance() {
    return this.balance;
  }
  
  /**
   * Update the account balance to reflect specific policies on the account;
   * for example, a savings account might add interest to the account
   * balance.
   * 
   */
  public abstract void update();
}