Question

Java

For this assignment you need to create at least 5 classes.

1.Create a vehicle class ( super class)
2,3. Create two sub classes ( car, bus , truck train or any) for vehicle class
4 Create a subclass (sportscar or schoolbus or Goodstrain or any) for car or bus

You need to use the following atleast for one class.

Use a protected variable
Add constructor for superclass and subclass
Override a method which displays a description about the vehicle
Use super keyword to call a superclass constructor
Use super keyword to call a superclass method to return the number of wheels

5.Create a vehicle test class to create object of subclass (sportscar or schoolbus or any) and an object for subclass (car or bus or any)

You need to invoke all classes using only 2 objects

Answer 1

Code is Given Below:

===========================

Vehicle.java

============================

//here vehicle is base class
public class Vehicle {
   //variables
   protected String name;
   protected int max_speed;
   protected int wheels;
  
   public Vehicle(String name, int max_speed) {
       this.name = name;
       this.max_speed = max_speed;
   }
   //getter and setter methods
  
   public String getName() {
       return name;
   }
   public int getWheels() {
       return wheels;
   }

   public void setWheels(int wheels) {
       this.wheels = wheels;
   }

   public void setName(String name) {
       this.name = name;
   }
   public int getMax_speed() {
       return max_speed;
   }
   public void setMax_speed(int max_speed) {
       this.max_speed = max_speed;
   }
   //tostring method
   public String toString() {
       return "Name is : "+name+"\nMax Speed is : "+max_speed;
       }

}

Car.java

=======================

//here Car is child class of vehicle
public class Car extends Vehicle {
   //variable
   protected int number_of_cylinders;
  
   public Car(String name, int max_speed, int number_of_cylinders) {
       super(name, max_speed);
       this.number_of_cylinders = number_of_cylinders;
   }

   //getter and setter method
   public int getNumber_of_cylinders() {
       return number_of_cylinders;
   }

   public void setNumber_of_cylinders(int number_of_cylinders) {
       this.number_of_cylinders = number_of_cylinders;
   }
   //tostring method
   public String toString() {
       return super.toString()+"\nNumber of Cylinders Are: "+number_of_cylinders+"\nNo. of Wheels : "+super.getWheels();
   }

}

Bus.java

=====================

public class Bus extends Vehicle{
   protected String fuelType;

   public Bus(String name, int max_speed, String fuelType) {
       super(name, max_speed);//calling super class constructor
       this.fuelType = fuelType;
   }
   //getter and setter method
   public String getFuelType() {
       return fuelType;
   }

   public void setFuelType(String fuelType) {
       this.fuelType = fuelType;
   }
   public String toString() {
       return super.toString()+"\nFuel Type: "+fuelType;
   }

}

SchoolBus.java

=====================

public class SchoolBus extends Bus {
   protected int seats;

   public SchoolBus(String name, int max_speed, String fuelType, int seats) {
       super(name, max_speed, fuelType);
       this.seats = seats;
   }
   public String toString() {
       return super.toString()+"\nSeats : "+seats;
   }
  
}

SportsCar.java

====================

public class SportsCar extends Car {
   protected double milage;

   public SportsCar(String name, int max_speed, int number_of_cylinders, double milage) {
       super(name, max_speed, number_of_cylinders);
       this.milage = milage;
   }
   public String toString() {
       return super.toString()+"\nMilage is : "+milage;
   }

}

Test.java

================

public class Test {
   public static void main(String[] args) {
       //creating object
       SportsCar sc=new SportsCar("BMW", 320, 12, 8);
       SchoolBus sb=new SchoolBus("mercedes", 120, "CNG", 32);
       Car c=new Car("Fiat", 180, 10);
       Bus b=new Bus("F8",120, "Petrol");
       Vehicle v=new Vehicle("Van",80);
       c.setWheels(4);
       //printing details
       System.out.println("Sport car ");
       System.out.println(sc);
       System.out.println("===========================");
       System.out.println("School bus ");
       System.out.println(sb);
       System.out.println("===========================");
       System.out.println("Car ");
       System.out.println(c);
       System.out.println("===========================");
       System.out.println("Bus ");
       System.out.println(b);
       System.out.println("===========================");
       System.out.println("Vehicle ");
       System.out.println(v);
       System.out.println("===========================");
      
   }

}

Output:

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Code Snapshot:

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