Java: Search, book, cancel hotel and flight reservations

// TravelApp.java
// Import the ArrayList class
import java.util.ArrayList;
// Import the Random class
import java.util.Random;

// Define the TravelApp class
public class TravelApp {
  // Declare an ArrayList to store flights
  private ArrayList flights;
  // Declare an ArrayList to store hotels
  private ArrayList hotels;

  // Constructor to initialize the ArrayLists
  public TravelApp() {
    // Initialize the flights ArrayList
    this.flights = new ArrayList();
    // Initialize the hotels ArrayList
    this.hotels = new ArrayList();
  }

  // Method to search for flights
  public void searchFlights(String origin, String destination, String date, int numPassengers) {
    // Print the search details for flights
    System.out.println("Searching for flights from " + origin + " to " + destination + " on " + date + " for " + numPassengers + " passengers.");
  }

  // Method to search for hotels
  public void searchHotels(String location, String checkIn, String checkOut, int numGuests) {
    // Print the search details for hotels
    System.out.println("Searching for hotels in " + location + " from " + checkIn + " to " + checkOut + " for " + numGuests + " guests.");
  }

  // Method to book a flight
  public void bookFlight(int flightNumber, String passengerName, String origin, String destination, String date, int numPassengers, double price) {
    // Create a new Flight object with the provided details
    Flight flight = new Flight(flightNumber, passengerName, origin, destination, date, numPassengers, price);
    // Generate a confirmation number
    int confirmationNumber = generateConfirmationNumber();
    // Set the confirmation number for the flight
    flight.setConfirmationNumber(confirmationNumber);
    // Add the flight to the flights ArrayList
    this.flights.add(flight);
    // Print the confirmation number for the booked flight
    System.out.println("Flight booked! Confirmation number: " + confirmationNumber);
  }

  // Method to book a hotel
  public void bookHotel(int hotelId, String guestName, String location, String checkIn, String checkOut, int numGuests, double price) {
    // Create a new Hotel object with the provided details
    Hotel hotel = new Hotel(hotelId, guestName, location, checkIn, checkOut, numGuests, price);
    // Generate a confirmation number
    int confirmationNumber = generateConfirmationNumber();
    // Set the confirmation number for the hotel
    hotel.setConfirmationNumber(confirmationNumber);
    // Add the hotel to the hotels ArrayList
    this.hotels.add(hotel);
    // Print the confirmation number for the booked hotel
    System.out.println("Hotel booked! Confirmation number: " + confirmationNumber);
  }

  // Method to cancel a reservation
  public void cancelReservation(int confirmationNumber) {
    // Loop through the flights ArrayList to find the reservation
    for (Flight flight : this.flights) {
      // If the confirmation number matches, remove the flight reservation
      if (flight.getConfirmationNumber() == confirmationNumber) {
        this.flights.remove(flight);
        // Print the cancellation message for the flight
        System.out.println("Flight reservation with confirmation number " + confirmationNumber + " cancelled.");
        return;
      }
    }
    // Loop through the hotels ArrayList to find the reservation
    for (Hotel hotel : this.hotels) {
      // If the confirmation number matches, remove the hotel reservation
      if (hotel.getConfirmationNumber() == confirmationNumber) {
        this.hotels.remove(hotel);
        // Print the cancellation message for the hotel
        System.out.println("Hotel reservation with confirmation number " + confirmationNumber + " cancelled.");
        return;
      }
    }
    // Print a message if no reservation is found with the provided confirmation number
    System.out.println("No reservation found with confirmation number " + confirmationNumber + ".");
  }

  // Method to generate a random 6-digit confirmation number
  private int generateConfirmationNumber() {
    // Create a Random object
    Random rand = new Random();
    // Generate and return a random 6-digit number
    return rand.nextInt(900000) + 100000;
  }
} 

// Flight.java
// Define the Flight class
public class Flight {
    // Declare an integer variable to store the flight number
    private int flightNumber;
    // Declare a string variable to store the passenger name
    private String passengerName;
    // Declare a string variable to store the origin of the flight
    private String origin;
    // Declare a string variable to store the destination of the flight
    private String destination;
    // Declare a string variable to store the date of the flight
    private String date;
    // Declare an integer variable to store the number of passengers
    private int numPassengers;
    // Declare a double variable to store the price of the flight
    private double price;
    // Declare an integer variable to store the confirmation number
    private int confirmationNumber;

    // Constructor to initialize the Flight object with provided details
    public Flight(int flightNumber, String passengerName, String origin, String destination, String date, int numPassengers, double price) {
        // Initialize the flight number
        this.flightNumber = flightNumber;
        // Initialize the passenger name
        this.passengerName = passengerName;
        // Initialize the origin of the flight
        this.origin = origin;
        // Initialize the destination of the flight
        this.destination = destination;
        // Initialize the date of the flight
        this.date = date;
        // Initialize the number of passengers
        this.numPassengers = numPassengers;
        // Initialize the price of the flight
        this.price = price;
    }

    // Method to get the flight number
    public int getFlightNumber() {
        return flightNumber;
    }

    // Method to get the passenger name
    public String getPassengerName() {
        return passengerName;
    }

    // Method to get the origin of the flight
    public String getOrigin() {
        return origin;
    }

    // Method to get the destination of the flight
    public String getDestination() {
        return destination;
    }

    // Method to get the date of the flight
    public String getDate() {
        return date;
    }

    // Method to get the number of passengers
    public int getNumPassengers() {
        return numPassengers;
    }

    // Method to get the price of the flight
    public double getPrice() {
        return price;
    }

    // Method to get the confirmation number
    public int getConfirmationNumber() {
        return confirmationNumber;
    }

    // Method to set the confirmation number
    public void setConfirmationNumber(int confirmationNumber) {
        this.confirmationNumber = confirmationNumber;
    }
} 

// Hotel.java
// Define the Hotel class
public class Hotel {
  // Declare an integer variable to store the hotel ID
  private int hotelId;
  // Declare a string variable to store the guest name
  private String name;
  // Declare a string variable to store the location of the hotel
  private String location;
  // Declare a string variable to store the check-in date
  private String checkIn;
  // Declare a string variable to store the check-out date
  private String checkOut;
  // Declare an integer variable to store the number of guests
  private int numGuests;
  // Declare a double variable to store the price of the stay
  private double price;
  // Declare an integer variable to store the confirmation number
  private int confirmationNumber;

  // Constructor to initialize the Hotel object with provided details
  public Hotel(int hotelId, String name, String location, String checkIn, String checkOut, int numGuests, double price) {
    // Initialize the hotel ID
    this.hotelId = hotelId;
    // Initialize the guest name
    this.name = name;
    // Initialize the location of the hotel
    this.location = location;
    // Initialize the check-in date
    this.checkIn = checkIn;
    // Initialize the check-out date
    this.checkOut = checkOut;
    // Initialize the number of guests
    this.numGuests = numGuests;
    // Initialize the price of the stay
    this.price = price;
  }

  // Method to get the hotel ID
  public int getHotelId() {
    return hotelId;
  }

  // Method to get the guest name
  public String getName() {
    return name;
  }

  // Method to get the location of the hotel
  public String getLocation() {
    return location;
  }

  // Method to get the check-in date
  public String getCheckIn() {
    return checkIn;
  }

  // Method to get the check-out date
  public String getCheckOut() {
    return checkOut;
  }

  // Method to get the price of the stay
  public double getPrice() {
    return price;
  }

  // Method to get the number of guests
  public int getNumGuests() {
    return numGuests;
  }

  // Method to get the confirmation number
  public int getConfirmationNumber() {
    return confirmationNumber;
  }

  // Method to set the confirmation number
  public void setConfirmationNumber(int confirmationNumber) {
    this.confirmationNumber = confirmationNumber;
  }
}

// Main.java
// Define the Main class
public class Main {
  // Main method, the entry point of the application
  public static void main(String[] args) {
    // Create a new TravelApp object
    TravelApp app = new TravelApp();
    // Search for flights from New York to London on 2022-09-01 for 1 passenger
    app.searchFlights("New York", "London", "2022-09-01", 1);
    // Search for hotels in London from 2022-08-01 to 2022-09-05 for 2 guests
    app.searchHotels("London", "2022-08-01", "2022-09-05", 2);
    // Book a flight with flight number 12345670 for Martin Nadine from New York to London on 2022-08-01 for 1 passenger with a price of $700.00
    app.bookFlight(12345670, "Martin Nadine", "New York", "London", "2022-08-01", 1, 700.00);
    // Book a flight with flight number 67843513 for Jennifer Ulrike from New York to London on 2022-08-01 for 1 passenger with a price of $655.00
    app.bookFlight(67843513, "Jennifer Ulrike", "New York", "London", "2022-08-01", 1, 655.00);
    // Book a hotel with hotel ID 98765432 for Martin Nadine in London from 2022-09-01 to 2022-09-05 for 1 guest with a price of $100.00
    app.bookHotel(98765432, "Martin Nadine", "London", "2022-09-01", "2022-09-05", 1, 100.00);
    // Cancel the reservation with confirmation number 12345670
    app.cancelReservation(12345670);
  }
}