Question

1- Use inheritance to implement the following classes:
A: A Car that is a Vehicle and has a name, a max_speed value and an instance variable called the

number_of_cylinders in its engine. Add public methods to set and get the values of these variables. When a car is printed (using the toString method), its name, max_speed and number_of_cylinders are shown.
B: An Airplane that is also a vehicle and has a name, a max_speed value and an instance variable called the number_of_engines it has. Add public methods to set and get the values of these variables. When an airplane is printed (using the toString method), its name, max_speed and number_of_engines are shown.

C: Write a VehicleDemo.java class that does the following:

1- Creates an instance of a Car and an Airplane class.

2- Assign values to the name, speed, number_of_cylinders (for the Car object) and

number_of_engines (for the Airplane object) variables.

3- Compares which vehicle goes faster and prints the result.

4- Prints the instances of the car and airplane classes.

NEXT

2- Add the following changes to the above problem:
A: Make the Vehicle an abstract class and add the following abstract method to it:

double runningCost(int hour); Which receives the hours of operation as a parameter and returns the running cost of the vehicle. The Car and Airplane classes will implement this method as follows:

1- For the Car class, define a private double constant called

COST_PER_CYLINDER_PER_HOUR = 10.5. The runningCost of a Car will be equal to:

hours * COST_PER_CYLINDER_PER_HOUR * number_of_cylinders

2- For the Airplane class, define a private double constant called

COST_PER_ENGINE_PER_HOUR = 25.3. The runningCost of an Airplane will be equal to:

hours * COST_PER_ ENGINE _PER_HOUR * number_of_engines

B: Write an interface called maintainable, which has the following method:

double maintenanceCost(double costPerUnit); It receives the cost per unit of an engine or cylinder and returns the maintenance cost. The Car and Airplane classes will implement this interface as follows:
1- For the Car class, the maintenance cost of a Car will be equal to:

costPerUnit * number_of_cylinders

2- For the Airplane class, the maintenance cost of an Airplane will be equal to: costPerUnit * number_of_engines

C: Add a String toString() method to the Vehicle class. When a Vehicle is printed, its name and max_speed are shown. Also, the String toString() methods of the Car and Airplane classes will show the following:

1- When a car is printed, its name, max_speed, number_of_cylinders and

COST_PER_CYLINDER_PER_HOUR are shown.

2- When an airplane is printed, its name, max_speed, number_of_engines and COST_PER_

ENGINE _PER_HOUR are shown.

D: Write a VehicleDemo.java class that does the following:

1- Creates an instance of a Car and an instance of an Airplane class.

2- Assigns values to the name, max_speed and number_of_cylinders instance variables of the

Car object and the name, max_speed and number_of_engines instance variables of the

Airplane object.

3- Calls all the methods of the Car and Airplane objects that return the values of their instance

variables and prints the results.

4- Calls the runningCost(5) of the Car and Airplane objects and prints the result.

5- Calls the maintenanceCost (30.0) of the Car and maintenanceCost (250.0) of the Airplane

objects and prints the result.

6- Defines a reference variable of type Vehicle and assigns it to an instance of a Car class.

Example: Vehicle v1 = new Car(...);

7- Prints v1. Notice whether the toString() method of the Vehicle class is called or the toString()

method of the Car class. Explain why it has been the case. In Object Oriented paradigm, what is this called?

Answer 1

Legacy is a programming build that product designers use to set up is-a connections between classifications. Legacy empowers us to get more-particular classes from more-nonexclusive ones. The more-particular class is a sort of the more-non specific classification. For instance, a financial records is a sort of record in which you can make stores and withdrawals. Additionally, a truck is a sort of vehicle utilized for pulling extensive things.

Legacy can dive through various levels, prompting to perpetually particular classifications. For instance, Figure 1 demonstrates auto and truck acquiring from vehicle; station wagon acquiring from auto; and dump truck acquiring from truck. Bolts point from more-particular "tyke" classes (let down) to less-particular "parent" classifications