This lab will use the concept of a doubly-linked list to simulate part of an air traffic control system. The program will manage the arrival and departure of flights into and out of your airspace.

The job of air traffic controller involves taking responsibility for all of the aircraft in a specific area of the airspace. The airspace for this problem will be a piece of the traffic corridor between the cities of Buffalo and Boston, Ma. Other controllers will have responsibility for the area to the east, west, north and south of you but your area will be under your exclusive control.

The program will accept certain commands from you and will display certain information to you in response. The commands and their responses will be as follows:

Command: Entering This command will signal that an aircraft has entered your airspace. You will be able to specify

The ID int of an aircraft

The altitude int thousands of feet

The speed int miles per hour

The name String (ex: U566)

Response: one aircraft will be added to your problem

Command: Leaving you will give the aircraft name

Response: it will be removed from your problem

Command: Show you will give the aircraft name

Response: all information for that aircraft will be displayed

Command: Display

Response: all aircraft in your problem will be displayed in a list

Implementation:

You will create a doubly-linked list in Java. You will implement an aircraft class which will take the place of the node class which was discussed. Objects of this aircraft class will be linked together in a list, as they are entered into the problem. When the Display command is entered, all the aircraft currently on the list will be displayed to the user.

Remember:

Use object reference variables for links between nodes

Implement two classes

linked list class which will be used by main to manipulate objects of the aircraft class

an aircraft class whose objects will contain aircraft information.

The main program should be the place where all of the conversation with the user takes place. This means that;

The linked list object will be able to return a single aircraft object in response to the Show command and will return an array of aircraft objects in response to the Display command.

The aircraft class should have a method that returns a String, suitable for displaying all of its information (used in the Show command) and another method that returns its name (used in the Display command). This will prevent the main program from having to know the details of the data inside the aircraft class.

There will be NO keyboard or display accessing in the aircraft class nor in the linked list class

Outline of classes

Main

Create linked list object

Loop while cmd not quit

Enter

Get AC info from user

Add an AC to list

Leave

Get AC name from user

Delete AC from list

Display

Get AC count from list

Loop from 1 to count

Show each AC

Display all existing AC in order of altitude

Show

Get AC name from user

Search list for name

Show AC found

When quitting, tell list to delete all remaining AC (if any).

Linked List

Get AC count

Add an AC

Delete an AC

Show AC by number

Search for AC by name and return the number

Delete all AC

Aircraft

Get name

Set name

Set type

Set altitude

Set speed

Testing:

In order to save a lot of typing, you may use single character commands (Ex: e for entering, l for leaving etc.).

You should be able to

entering the first aircraft

entering the second aircraft

entering the third aircraft

display all three, in altitude-order

show the first

show the third

leaving the second

show the second (present an appropriate error message)

display both remaining

leaving the third

display the remaining one

leaving the first

display the empty list