Problem Definition
It is required to simulate a limited number of devices connected to a router’s Wi-Fi using Java threading and semaphore. Routers can be designed to limit the number of open connections. For example, a Router may wish to have only N connections at any point in time. As soon as N connections are made, the Router will not accept other incoming connections until an existing connection is released. Explain how semaphores can be used by a Router to limit the number of concurrent connections
The following rules should be applied:
➔ The Wi-Fi number of connected devices is initially empty.
➔ If a client is logged in (print a message that a client has logged in) and if it can be served ➔ (means that it can reach the internet), then the client should perform the following
activities:
◆ Connect
◆ Performonlineactivity
◆ Logout
➔ Note: these actions will be represented by printed messages, such that there is a
random
➔ waiting time between the printed messages when a client connects, do some online
➔ activities and logged out.
➔ If a client arrives and all connections are occupied, it must wait until one of the currently ➔ available clients finish his service and leave.
➔ After a client finishes his service, he leave and one of the waiting clients (if exist) will
➔ connect to the internet.
Solution Design
You program must contain the following classes:
1. Router Class: that contains a list of connections and methods to occupy a connection and release a connection.
2. Semaphore Class: as given the synchronization lab.
3. Device Class: represent different devices (threads) that can be connected to the router;
each device has its own name (i.e. C1) and type (i.e. mobile, pc, tablet…) and it may perform three activities: connect, perform online activity and disconnect/logout.
4. Network Class: this class contains the main method in which the user is asked for two
inputs:
- ● N: max number of connections a router can accept
- ● TC: total number of devices that wish to connect).
- ● TC lines that contain: name of each device, and its type
Program Output
You will print the output logs in a file, which simulates the execution order of the devices threads and the printed messages of each device
NOTE THAT: This is just an example not the only scenario that can be applied.
Sample Input
What is the number of WI-FI Connections?
2
What is the number of devices Clients want to connect? 4
C1 mobile
C2 tablet
C3 pc
C4 pc
Sample Output
- (C1)(mobile)arrived - (C2)(tablet)arrived - Connection 1: C1 Occupied - Connection 2: C2 Occupied - C4(pc) arrived and waiting - C3(pc)arrived and waiting - Connection 1: C1 login - Connection 1: C1 performs online activity - Connection 2: C2 login - Connection 2: C2 performs online activity - Connection 1: C1 Logged out - Connection 1 : C4 Occupied - Connection 1 : C4 log in - Connection 1 : C4 performs online activity - Connection 2: C2 Logged out - Connection 2: C3 Occupied
