Java Reference
In-Depth Information
thread.sleep(1000);
working
#
false
;
this
.repaint();
// notifies the Client that the task has been completed
this
.notifyObservers("WORKDONE");
}
catch
(InterruptedException ie) { ie.printStackTrace(); }
}
}
Class
Client
extends class
EventProcess
. It holds a reference to the server
object and implements the
run()
method. Every 1500 milliseconds the client
sends a request to the Server to execute a task and visualizes string
DOSERVICE
in the graphical user interface.
package
parking;
public class
Client
extends
EventProcess {
Server server; // a reference to the Server object
public
Client(String name, Server server) {
super
(name);
this
.server
#
server;
this
.attachTo(server); // attaches itself to the event
// raised by the Server
}
// this method implements the client's behaviour
public void
run() {
while
(alive)
try
{
server.doService();
this
.waitEvent(server, "WORKDONE");
thread.sleep(1500);
}
catch
(InterruptedException ie) { ie.printStackTrace(); }
}
}
11.5
■
Prototype 2: Graphical animation
The second prototype simulates the behaviour of the physical devices, the
controller and the car and animates them in a graphical user interface.
11.5.1
Analysis
Let's consider the dynamic of each subsystem. Figure 11.4 depicts the finite
state automata of
PhotoCell
,
TicketDispenser
and
StoppingBar
respectively.
Ovals represent states, while rectangles represent state transitions. State
names are in bold upper case. Two labels describe state transitions. The
