Lab Assignment 9

(April 19/April 20)

 

Note: You can do this lab on your own or with a partner.

 

The main purpose of this lab is to understand more thoroughly some of the inheritance concepts we covered in class. For today's lab we will work with following four classes.

 

1. Inventory
2. Vehicle
3. Car
4. Bicycle

 

The main functionalities of the classes are explained below. Based on this, you will design and implement these classes. I will also let you think more about the method signatures.

 

Vehicle

This class should abstract the main similarities between a car and a bicycle. You should decide some of the fields and methods of this class. All the fields of this class should be declared private. Though there could be a lot of fields, just limit yourself to maximum 3 or 4.

• Your constructor should initialize all these fields.
• Amongst other methods, this class must have a print() method that should print information about all the fields. This method should be public.

 

Car

This class should be a subtype of Vehicle class. It should extend functionality of Vehicle class by adding fields and methods that are more relevant to a car. Again limit yourself to just 2-3 more fields and methods.

• Note that you will have to explicitly call superclass constructor to initialize fields. (Refer to lecture notes for how to do this).
• There should be a print method that prints complete car information, i.e. information for both Car fields and Vehicle fields. Thus, the print method in car should call print method from its superclass. (Refer to lecture notes for how to do this).

 

Bicycle

This class should also subtype Vehicle class. It should extend functionality of Vehicle class by adding fields and methods that are more relevant to a bicycle. Limit yourself to just 2-3 more fields and methods.

• Note that you will have to explicitly call superclass constructor to initialize fields.
• There should be a print method that prints complete bicycle information.

 

Inventory

The inventory class will keep track of all the vehicles. This class should use an ArrayList to store information about vehicles.

• There should be just one add() method that should accept objects of both Car and Bicycle Type.
• There should be a list() method that would print information about all the vehicles.Implement an if statement in the list() method that should be able to differentiate between the two type of objects. If the objects are of type car the method will print "This information is about a car" and then the other information else if the objects are of type bicycle it should print information "This information is about a bicycle" Note that information printed should be complete i.e. it should print information about all the fields of a car or a bicycle and their superclass vehicle.  (Note the purpose of this method is to make sure you know how to access the methods in a super object from the sub class, and to be able to distinguish between the objects of different subclasses).

 

Your class diagram should be as shown below: