Design a Ship class with the following members:

• Two private fields: name of the ship and the year it was built.
• A no-arg constructor and a constructor that takes two arguments (name and year).
• Appropriate getters and setters.
• A toString method that overrides the toString method in Object and displays the ship's name and the year it was built.

Design a CruiseShip class that extends the Ship class. The CruiseShip class should have the following members:

• A field for the maximum number of passengers (int).
• A constructor and appropriate accessors and mutators.
• A toString method that overrides the toString method in the base class. The CruiseShip class's toString method should display only the ship's name and the maximum number Of passengers.

Design a CargoShip class that extends the Ship class. The CargoShip class should habe the following members:

•A field for the cargo capacity in tonnage (int).
•A constructor and appropriate accessors and mutators.
•A toString method that overrides the toString method in the base class. The CargoShip class's toString method should display only the ship's name and the ship's cargo capacity.

Required:
Demonstrate the classes in a program that has a Ship array. Assign various Ship, CruiseShip and CargoShip objects to the array elements. The program should then step through the array, calling each object's toString method.

In this exercise we have to use the knowledge of programming in the Java language, in this way we find the code as:

The code can be found in the figure attached below.

So to make it easier the code will be rewritten below as:

// Ship.java

public class Ship {

//field to store the name of the ship

private String name;

// filed to store the built on date as string

private String builtOn;

// constructor for ship takes name and built on date as argument

public Ship(String name, String builtOn) {

this.name = name;

this.builtOn = builtOn;

}

// getter to get the name of the ship

public String getName() {

return name;

}

// setter to set the name of the ship

public void setName(String name) {

this.name = name;

}

// getter method to get the built on date of the ship

public String getBuiltOn() {

return builtOn;

}

// setter method to set the built on date of the ship

public void setBuiltOn(String builtOn) {

this.builtOn = builtOn;

}

// to string method to print the ship as as string

public String toString() {

return "Ship [name=" + name + ", builtOn=" + builtOn + "]";

}

// CruiseShip.java

public class CruiseShip extends Ship {

// field to store the max number of passenger in the ship

private int maxNumberOfPassenger;

// constructor for cruise ship takes name , builton date and max number of passenger as argument

public CruiseShip(String name, String builtOn, int

axNumberOfPassenger) {

super(name, builtOn);

this.maxNumberOfPassenger = maxNumberOfPassenger;

}

// getter method to get the maximum number of passenger in the ship

public int getMaxNumberOfPassenger() {

return maxNumberOfPassenger;

}

// setter mehtod to set the maximum number of passenger in the ship

public void setMaxNumberOfPassenger(int maxNumberOfPassenger) {

this.maxNumberOfPassenger = maxNumberOfPassenger;

}

// to string method to print the cruise ship as string

atOverride //replace the at with at symbol

public String toString() {

return (super.toString() + ", " + "CruiseShip [maxNumberOfPassenger=" + maxNumberOfPassenger + "]");

}

// CargoShip.java

public class CargoShip extends Ship{

// field to store the capacity of cargo ship

private int cargoCapacity;

// constructor for cargo ship takes name , builton date and capacity as argumnet

public CargoShip(String name, String builtOn, int cargoCapacity) {

super(name, builtOn);

this.cargoCapacity = cargoCapacity;

}

// getter method to get the capacity of cargo ship

public int getCargoCapacity() {

return cargoCapacity;

}

// setter method to set the capacity of cargo ship

public void setCargoCapacity(int cargoCapacity) {

this.cargoCapacity = cargoCapacity;

}

// to string mehtod to print the cargo ship object as string

atOverride // replace at with its symbol

public String toString() {

return (super.toString() + ", " + "CargoShip [cargoCapacity=" + cargoCapacity + " tonnage]");

}

// Test.java

import java.util.ArrayList;

import java.util.List;

public class Test {

// driver mehtod to test declared class

public static void main(String args[]){

// declare arraylist of ship to store the ships

List<Ship> ships = new ArrayList<Ship>();

// adding the ship into the arraylist

ships.add(new Ship("ShipA", "04/04/2018"));

ships.add(new Ship("ShipB","05/04/2018"));

ships.add(new CruiseShip("CruiseShipA", "03/04/2018", 14));

ships.add(new CruiseShip("CruiseShipB", "04/04/2018", 24));

ships.add(new CargoShip("CargoShipA", "02/04/2018", 40));

ships.add(new CargoShip("CargoShipB", "04/04/2018", 12));

// printing the ships by iterating over the array list of ships

for (int i = 0; i < ships.size(); i++){

System.out.println(ships.get(i));

}

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