Java Higher Order Functions and Lambda (Streams)

  package model;

public class Movie {
    private String title;
    private String director;
    private String genre;
    private int releaseYear;
    private double rating;

    public Movie(String title, String director, String genre, int releaseYear, double rating) {
        this.title = title;
        this.director = director;
        this.genre = genre;
        this.releaseYear = releaseYear;
        this.rating = rating;
    }

    public String getTitle() {
        return title;
    }

    public String getDirector() {
        return director;
    }

    public String getGenre() {
        return genre;
    }

    public int getReleaseYear() {
        return releaseYear;
    }

    public double getRating() {
        return rating;
    }

    @Override
    public String toString() {
        return title + " (" + releaseYear + ") - Directed by " + director + ", Genre: " + genre + ", Rating: " + rating;
    }
}

package model;

import java.util.ArrayList;
import java.util.List;

public class MovieStore {
    private List<Movie> movies;

    public MovieStore() {
        this.movies = new ArrayList<>();
    }

    public void addMovie(Movie movie) {
        movies.add(movie);
    }

    public List<Movie> filterByGenre(String genre) {
        return movies.stream()
                .filter(movie -> movie.getGenre().equalsIgnoreCase(genre))
                .toList();
    }

    public List<Movie> sortByReleaseYear() {
        return movies.stream()
                .sorted((movie1, movie2) -> Integer.compare(movie1.getReleaseYear(), movie2.getReleaseYear()))
                .toList();
    }

    public List<Movie> getTopRatedMovies(int n) {
        return movies.stream()
                .sorted((movie1, movie2) -> Double.compare(movie2.getRating(), movie1.getRating()))
                .limit(n)
                .toList();
    }
}

import java.util.List;

import model.Movie;
import model.MovieStore;

public class Main {
    public static void main(String[] args) {
        Movie movie1 = new Movie("Inception", "Christopher Nolan", "Sci-Fi", 2010, 8.8);
        Movie movie2 = new Movie("The Dark Knight", "Christopher Nolan", "Action", 2008, 9.0);
        Movie movie3 = new Movie("The Matrix", "Lana Wachowski, Lilly Wachowski", "Sci-Fi", 1999, 8.7);
        Movie movie4 = new Movie("Pulp Fiction", "Quentin Tarantino", "Crime", 1994, 8.9);


        MovieStore movieStore = new MovieStore();
        movieStore.addMovie(movie1);
        movieStore.addMovie(movie2);
        movieStore.addMovie(movie3);
        movieStore.addMovie(movie4);


        List<Movie> sciFiMovies = movieStore.filterByGenre("Sci-Fi");
        List<Movie> sortedMovies = movieStore.sortByReleaseYear();
        List<Movie> topRatedMovies = movieStore.getTopRatedMovies(3);


        System.out.println("Sci-Fi Movies:");
        sciFiMovies.forEach(movie -> System.out.println(movie));


        System.out.println("\nSorted by Release Year:");
        sortedMovies.forEach(movie -> System.out.println(movie));


        System.out.println("\nTop Rated Movies:");
        topRatedMovies.forEach(movie -> System.out.println(movie));

    }
}