UpAndDown

Elevator management service simulation.

Concept

A ElevatorControlSystem class manages multiple functioning elevators, persons can submit Pickup requests to the system and the system will send an elevator to pick them up.

The system will choose if possible, the first closest available elevator, if no elevator is available, the closest one will be chosen, and will come after processing its current pending requests.

Pickup requests have to specify the floor on which the request is made, and the destination floor.

Usage

ElevatorControlSystem provides 4 main functionalities :

pickup(int pickupFloor, int destinationFloor) : Send a pickup request, the system will send an elevator as soon as possible.
update(int elevatorId, int floorNumber) : Set an elevator to a particular floor.
status() / status(int elevatorId) : Get the current status of all the elevators / one elevator. The data returned for each elevator is a Map on which the static keys are defined in the Elevator class, the keys are :

ELEVATOR_ID_KEY
CURRENT_FLOOR_KEY
CURRENT_DIRECTION_KEY
CURRENT_PICKUP_KEY
PENDING_PICKUPS_KEY

step() : Time control the simulation.

Compiling and Testing

The project is using Apache Maven management tool. To create the distribution of the project :

mvn clean package

Code examples can be found in the src/test/ directory. There are some test simulations I left there that I used when testing, plus some explanations.

Utils to print the status and the Elevators can be found in me.kgdo.upanddown.util.PrettyPrintUtils.

Example running

        // ElevatorControSystem takes the number of elevators running in parameter.
        ElevatorControlSystem ecs = new ElevatorControlSystem(4);

        ecs.pickup(3, 6);
        // Elevator 0 is chosen for the pickup because first available.
        ecs.step();
        ecs.step();
        ecs.step();
        prettyPrintStatus(ecs);

        ecs.pickup(0, 8);
        // Elevator 1 is chosen for the pickup because 0 is busy.
        ecs.step();
        ecs.step();
        ecs.step();
        ecs.step();
        ecs.step();
        ecs.step();
        ecs.step();
        ecs.step();
        ecs.step();
        ecs.step();
        prettyPrintStatus(ecs);

        ecs.pickup(0, 5);
        // Elevator 2 is chosen for the pickup because it's the closest available.
        ecs.step();
        prettyPrintStatus(ecs);

Comments

I tried to put comments on the algorithmic part, so Finding an elevator, and the elevator movements logic.

Time

Started at : Sat-21-May 15:11 (British Standard Time)

Finished at : Sat-21-May 19:43 (British Standard Time)

4h32min spent for the coding, tests, and main documentation part.

newkek/upanddown