Question

Create a short program in Java which contains the below information:

- Has one abstract and two regular classes

- Has two interfaces (the two regular classes have to implement at least one interface

- At least one regular class must implement both interfaces

- The two classes have to extend the abstract class

- The abstract class must have a method

- At least one interface must have a method

- At least two fields in each class, this includes the superclass

- All the fields are instantiated within the constructor

Answer 1

interface 1 :

Vehicle.java

public interface Vehicle {

// mothod inside interface

   void getManufacturer();
}

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interface 2 :

VehicleParts.java

public interface VehicleParts {

// two methods inside interface

   void getNumberOfWheels();
   void getVehicleBodyDetails();
  
}

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abstract class

Offer.java

public abstract class Offer {
// variable inside abstract class
   boolean isOffer;
// abstract method inside abstract class
   abstract void getOfferDetails();
  
}
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regular class 1:

Car.java

public class Car extends Offer implements Vehicle, VehicleParts {

// variables in the class

String varient;
   double price;
   Offer offer;

// parameterised constructor and is instantiated

   public Car(String varient, double price, Offer offer) {
  
       this.varient = varient;
       this.price = price;
       this.offer = offer;
   }

// default constructor

   public Car() {
       super();
   }

// abstract class method implementation

@Override
   void getOfferDetails() {
       System.out.println("No offers available !");

   }

// method inside interface vehicleParts and locally implemented

   @Override
   public void getNumberOfWheels() {
       System.out.println("This is a car and have 4 wheels.");

   }

// method inside interface vehicleParts and locally implemented

   @Override
   public void getVehicleBodyDetails() {
       System.out.println("High quality Metal Body.");

   }

// method inside interface vehicle and locally implemented

   @Override
   public void getManufacturer() {
       System.out.println("This Car is manufactured by TOYOTA.");

   }

}
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regular class2

Bike.java

public class Bike extends Offer implements Vehicle {

// variables in the class  

String model;
   String brakeSystem;
   Offer offer;

// parameterised constructor and is instantiated

   public Bike(String model, String brakeSystem, Offer offer) {
       this.model = model;
       this.brakeSystem = brakeSystem;
       this.offer = offer;
   }

//default constructor

   public Bike() {
       super();
   }

// abstract class method implementation

   @Override
   void getOfferDetails() {
       System.out.println("Get 5000* offer. Expire soon !");

   }

// method inside interface vehicle and locally implemented

   @Override
   public void getManufacturer() {
       System.out.println("This is manufactured by 'ROYAL ENFIELD'");

   }

}
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test class

Showroom.java

public class Showroom {

   public static void main(String[] args) {
       Car newCar = new Car();
       Bike newBike = new Bike();

       // set values to the fields in Car
       newCar.varient = "XZPlus";
       newCar.price = 1000000;
       newCar.isOffer = false;

       // set values to the fields in bike
       newBike.model = "Thunder";
       newBike.brakeSystem = "ABS";
       newBike.isOffer = true;

       // print car details
       newCar.getManufacturer();
       newCar.getNumberOfWheels();
       newCar.getOfferDetails();

       System.out.println("\n");

       // print bike details
       newBike.getManufacturer();
       newBike.getOfferDetails();

   }

}