/** Make a new ticket available at the specified price for the specified flight. */
public synchronized void publishTicket(String flightCode, int price) {
Ticket ticket = new Ticket(flightCode, currentTicketNumber++, price);
Set<Ticket> ticketsForFlightCode = ticketsByFlightCode.get(ticket.getFlightCode());
if (ticketsForFlightCode == null) {
ticketsForFlightCode = new LinkedHashSet<Ticket>();
ticketsByFlightCode.put(ticket.getFlightCode(), ticketsForFlightCode);
}
ticketsForFlightCode.add(ticket);
}
