// TODO replace with JSR 303
public void validateEnterBookingDetails(ValidationContext context) {
MessageContext messages = context.getMessageContext();
if (checkinDate.before(today())) {
messages.addMessage(new MessageBuilder().error().source(
"checkinDate").code("booking.checkinDate.beforeToday")
.build());
} else if (checkoutDate.before(checkinDate)) {
messages.addMessage(new MessageBuilder().error().source(
"checkoutDate").code(