Understanding class definitions - Objects First with Java: A Practical Introduction Using BlueJ - page 41

Code 2.8
continued
A more sophisticated
TicketMachine

/**
* Receive an amount of money in cents from a customer.
* Check that the amount is sensible.
*/
public void insertMoney( int amount)
{

if (amount > 0) {
balance = balance + amount;

}
else {
System.out.println( "Use a positive amount rather than: " +
amount);

}

}

/**
* Print a ticket if enough money has been inserted, and
* reduce the current balance by the ticket price. Print
* an error message if more money is required.
*/
public void printTicket()
{

if (balance >= price) {
// Simulate the printing of a ticket.
System.out.println( "##################" );
System.out.println( "# The BlueJ Line" );
System.out.println( "# Ticket" );
System.out.println( "# " + price + " cents." );
System.out.println( "##################" );
System.out.println();

// Update the total collected with the price.
total = total + price;
// Reduce the balance by the price.
balance = balance - price;

}
else {
System.out.println( "You must insert at least: " +
(price - balance) + " cents." );

}

}

/**
* Return the money in the balance.
* The balance is cleared.
*/