Question

Can someone tell me how to create a test for the following Hotel classes that test all of the methods?

public class Bed



{

  private String type;

  private static final String[] TYPES ={"Single", "Double", "King Size"};



  public Bed(String type)

  {

    this.type = type;

  }



  public boolean isSingle()

  {

    return type.equals(TYPES[0]);

  }



  public boolean isDouble()

  {

    return type.equals(TYPES[1]);

  }



  public boolean isKingSize()

  {

    return type.equals(TYPES[2]);

  }



}

public class Guest

{
private String name;

public Guest (String name)
{
    this.name = name;
}

public String getName()
{
    return name;
}

//checks if instance is an object of guest
public boolean equals(Object obj)
{
    if (!(obj instanceof Guest))
      return false;
    Guest other = (Guest) obj;
    return this.name.equals(other.name); //checks the instance of the object not the actual object which is the guest//
}
}

public class Room

{

  private int number;

  private Bed bed;

  private Guest guest;

  public static final double[] PRICES = {59.50, 72.40, 89.00};

  public static final String[] BED_TYPES = {"Single", "Double", "King Size"};

  public Room (int number, String bedType)

  {

    this.number = number;

    this.bed = new Bed(bedType);

    this.guest = null;

  }



  public int getNumber()

  {

    return number;

  }

  public int getFloor()

  {

    int floor = number/100;

    return floor;



  }

public double getPrice()

{

  if (bed.isSingle())

  {

    return PRICES[0];

  }

 else if (bed.isDouble())

  {

    return PRICES[1];

  }

  else {

    return PRICES[2];

  }



}

public boolean isOccupied()

{

  return  guest != null;

}

public void registerGuest(Guest guest)

{

  this.guest = guest;

}



public void vacate()

  {

    guest = null;

  }



public String getBedType()

{

  if (bed.isSingle())

  {

    return BED_TYPES[0];

  }

  else if (bed.isDouble())

  {

    return BED_TYPES[1];

  }

  else

  {

    return BED_TYPES[2];

  }

}

 public Guest getGuest()

 {

   return guest;

 }

}

import java.util.ArrayList;



public class Hotel

{

  private String name;

  private Room[] rooms;



  private Hotel(String name, Room[] rooms)

  {

    this.name = name;

    this.rooms = rooms;

  }



  public String getName()

  {

    return name;

  }



  public int getNumberOfRooms()

  {

    return rooms.length;

  }



  public int getNumberOfAvailableRooms()

  {

    int count = 0;

    for (int i=0; i<rooms.length;i++)

    {

      if (!rooms[i].isOccupied())

      {

        count++;

      }

    }

    return count;

  }



  public Room getFirstAvailableRoom()

  {

    for (int i=0; i<rooms.length;i++)

    {

      if (!rooms[i].isOccupied())

      {

        return rooms[i];

      }

    }

    return null;

  }



  public Room getFirstAvailableRoom(double maxPrice)

  {

    for (int i=0; i<rooms.length;i++)

    {

      if (!rooms[i].isOccupied() && rooms[i].getPrice() <=maxPrice)

      {

        return rooms[i];

      }

    }

    return null;

  }



  public Room[] getAllAvailableRooms(String bedType)

  {

    ArrayList<Room> list = new ArrayList<>();

    for (int i = 0; i < rooms.length; i++)

    {

      if (!rooms[i].isOccupied() && rooms[i].getBedType().equals(bedType))

      {

      list.add(rooms[i]);

      }

    }

    return (Room[])list.toArray();

  }



  public boolean hasGuest(Guest guest)

  {



    for (int i = 0; i < rooms.length; i++)

    {

      if (rooms[i].isOccupied() && rooms[i].getGuest().equals(guest))

      {

       return true;

      }

    }

    return false;

  }



  public Room getRoom(Guest guest)

  {



    for (int i = 0; i < rooms.length; i++)

    {

      if (rooms[i].isOccupied() && rooms[i].getGuest().equals(guest))

      {

        return rooms[i];

      }

    }

    return null;

  }

}

Answer 1

Here in this given set of classes, we can't instantiate an object for class Hotel in order to test all the hotel related methods, it is because the Hotel class is having a private constructor. If we are allowed to make a change the constructor to public, then we can test the given Hotel class like the below given code.

import java.util.ArrayList;


class Main {

    public static void main(String[] args) {

        //creating guests objects
        Guest guest1 = new Guest("Guest One");  
        Guest guest2 = new Guest("Guest Two");
        Guest guest3 = new Guest("Guest Three");
        Guest guest4 = new Guest("Guest Four");


        //creating objects for Room for the Hotel 
        Room room1 = new Room(1,Room.BED_TYPES[0]);
        Room room2 = new Room(2,Room.BED_TYPES[1]);
        Room room3 = new Room(3,Room.BED_TYPES[2]);
        Room room4 = new Room(4,Room.BED_TYPES[2]);

        
        //register the created Guests in the created Rooms
        room1.registerGuest(guest2);
        room2.registerGuest(guest1);
        room3.registerGuest(guest3);
        
        //creating Room's array
        Room[] rooms = new Room[]{room1,room2,room3,room4};

        //Creating an Object for Hotel class with the above Rooms array
        Hotel hotel = new Hotel("Hotel Oberoi",rooms);

        //Calling all the methods of Hotel class
        System.out.println("\nHotel Name" + hotel.getName());

        System.out.println("\nTotal No:Of Rooms: "+hotel.getNumberOfRooms());

        System.out.println("\nNo:Of Available Rooms :" + hotel.getNumberOfAvailableRooms());

        System.out.println("\nDoes Hotel has Guest One?  " + hotel.hasGuest(guest1));

        System.out.println("\nIn which room Guest One staying? " + hotel.getRoom(guest1));

        Room[] availableRooms = hotel.getAllAvailableRooms(Room.BED_TYPES[2]);

        System.out.println("\nAvailable Rooms:");
        if(availableRooms.length < 1)
            System.out.println("No Rooms!");
        else
            for(Room room: availableRooms)
                System.out.println(room);


        System.out.println("\nFirst Available Rooms: " + hotel.getFirstAvailableRoom());

    }
}

class Bed {

    private static final String[] TYPES = {"Single", "Double", "King Size"};
    private String type;

    public Bed(String type) {
        this.type = type;
    }

    public boolean isSingle() {
        return type.equals(TYPES[0]);
    }

    public boolean isDouble() {
        return type.equals(TYPES[1]);
    }

    public boolean isKingSize() {
        return type.equals(TYPES[2]);
    }
}

class Guest {
    private String name;

    public Guest(String name) {
        this.name = name;
    }

    public String getName() {
        return name;
    }

    //checks if instance is an object of guest
    public boolean equals(Object obj) {
        if (!(obj instanceof Guest))
            return false;
        Guest other = (Guest) obj;
        return this.name.equals(other.name); //checks the instance of the object not the actual object which is the guest//
    }

    @Override
    public String toString() {
        return "Guest{" +
                "name='" + name + '\'' +
                '}';
    }
}

class Room {

    public static final double[] PRICES = {59.50, 72.40, 89.00};
    public static final String[] BED_TYPES = {"Single", "Double", "King Size"};
    private int number;
    private Bed bed;
    private Guest guest;

    public Room(int number, String bedType) {
        this.number = number;
        this.bed = new Bed(bedType);
        this.guest = null;
    }

    public int getNumber() {
        return number;
    }

    public int getFloor() {
        int floor = number / 100;
        return floor;
    }

    public double getPrice() {
        if (bed.isSingle()) {
            return PRICES[0];
        } else if (bed.isDouble()) {
            return PRICES[1];
        } else {
            return PRICES[2];
        }
    }

    public boolean isOccupied() {
        return guest != null;
    }

    public void registerGuest(Guest guest) {
        this.guest = guest;
    }

    public void vacate() {
        guest = null;
    }

    public String getBedType() {
        if (bed.isSingle()) {
            return BED_TYPES[0];
        } else if (bed.isDouble()) {
            return BED_TYPES[1];
        } else {
            return BED_TYPES[2];
        }
    }

    public Guest getGuest() {
        return guest;
    }

    @Override
    public String toString() {
        return "Room{" +
                "number=" + number +
                ", bed=" + getBedType() +
                ", guest=" + guest +
                '}';
    }
}


class Hotel {

    private String name;
    private Room[] rooms;

    public Hotel(String name, Room[] rooms) {
        this.name = name;
        this.rooms = rooms;
    }


    public String getName() {
        return name;
    }

    public int getNumberOfRooms() {
        return rooms.length;
    }

    public int getNumberOfAvailableRooms() {
        int count = 0;

        for (int i = 0; i < rooms.length; i++) {
            if (!rooms[i].isOccupied()) {
                count++;
            }
        }
        return count;
    }

    public Room getFirstAvailableRoom() {

        for (int i = 0; i < rooms.length; i++) {
            if (!rooms[i].isOccupied()) {
                return rooms[i];
            }
        }
        return null;
    }

    public Room getFirstAvailableRoom(double maxPrice) {

        for (int i = 0; i < rooms.length; i++) {
            if (!rooms[i].isOccupied() && rooms[i].getPrice() <= maxPrice) {
                return rooms[i];
            }
        }
        return null;
    }

    public Room[] getAllAvailableRooms(String bedType) {

        ArrayList<Room> list = new ArrayList<>();
        for (int i = 0; i < rooms.length; i++) {
            if (!rooms[i].isOccupied() && rooms[i].getBedType().equals(bedType)) {
                list.add(rooms[i]);
            }
        }
        Room[] rooms = new Room[list.size()];
        return list.toArray(rooms);     //changed due to java.lang.ClassCastException:
    }

    public boolean hasGuest(Guest guest) {

        for (int i = 0; i < rooms.length; i++) {
            if (rooms[i].isOccupied() && rooms[i].getGuest().equals(guest)) {
                return true;
            }
        }
        return false;
    }

    public Room getRoom(Guest guest) {

        for (int i = 0; i < rooms.length; i++) {
            if (rooms[i].isOccupied() && rooms[i].getGuest().equals(guest)) {
                return rooms[i];
            }
        }
        return null;
    }
}

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OUTPUT: