Car parking - Software Development Case Studies in Java - page 297

public Controller(String name, TrafficLight tLight,
PhotoCell inPhC, PhotoCell outPhC, StoppingBar
bar, TicketDispenser dispenser) {
super (name);
trafficLight # tLight;
inPhotoCell # inPhC;
outPhotoCell # outPhC;
stoppingBar # bar;
ticketDispenser # dispenser;
// attaches to the events raised by the physical devices
this .attachTo(inPhC);
this .attachTo(outPhC);
this .attachTo(bar);
this .attachTo(dispenser);
}
public void run() {
trafficLight.setGreen();
while (alive) {
switch (phase) {
case 1:
// waits for a new car to cross the first photocell
waitEvent(inPhotoCell, "OCCUPIED");
phase # 2; break ;
case 2:
// waits for a new car to clear the first photocell
waitEvent(inPhotoCell, "CLEARED");
// set the trafficLight to red
trafficLight.setRed();
// a new car proceeds to the ticket dispenser
ticketDispenser.deliver();
phase # 3; break ;
case 3:
// waits for the ticket dispenser to deliver the
// ticket
waitEvent(ticketDispenser, "DELIVERED");
phase # 4; break ;
case 4:
// waits for the car to withdraw the ticket
waitEvent(ticketDispenser, "WITHDRAWN");
// the car has withdrawn the ticket; it raises the
// stopping bar
stoppingBar.raise();
phase # 5; break ;
case 5:
// the controller waits for the stopping bar to be up