Clase Song como clase interna en Album en Java

Clase 12 de 40 • Curso Avanzado de Java SE

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Programación Avanzada en Java: Clases e Interfaces
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Tomar examen

Spotify tiene una relación Album - Song en donde Song será una clase que solo es utilizada en Album pues la definición de este es una colección de Song’s.

¿Cuál sería la forma más adecuada de tratar la clase Song si esta solamente se utilizará en Album?

Realiza el código que resuelva esto y compartelo en la sección de discuciones.

Comentarios

César Espitia

student•

Acá dejo mi versión de la implementación de la clase: Album

public class Album {

    private String name;
    private String author;
    private int year;
    private Song[] songs;

    public Album(String name, String author, int year) {
        this.name = name;
        this.author = author;
        this.year = year;
    }

    public void setAlbum(String[] names, int[] durations) {
        Song[] songs = new Song[names.length];
        for (int i = 0; i < names.length; i++) {
            songs[i] = new Song(names[i], durations[i]);
        }
        this.songs = songs;
    }

    private String getAlbum() {
        StringBuilder sb = new StringBuilder();
        for (Song song : songs) {
            sb.append(song);
        }
        return sb.toString();
    }

    public String toString() {
        return "\nALBUM: " + name +
                "\nAUTHOR: " + author +
                "\nYEAR: " + year +
                "\n\n::SONGS::\n" + getAlbum();
    }


    private static class Song {

        private String name;
        private int duration;

        private Song(String name, int duration) {
            this.name = name;
            this.duration = duration;
        }

        public String toString() {
            return "\nName: " + name +
                    "\nDuration: " + duration + " seconds\n";
        }
    }
}

Main

    public static void main(String[] args) {
        String[] names = {"Uno", "Divenire", "Monday", "Andare", "Rose", "Primavera", "Oltremare", "L'origine Nascosta", "Fly", "Ascolta", "Ritornare", "Svanire"};
        int[] durations = {228, 402, 355, 422, 256, 444, 660, 192, 279, 289, 532, 449};
        Album album = new Album("Divenire","Ludovico Einaudi",2006);
        album.setAlbum(names, durations);
        System.out.println(album);
    }

Nicolas Díaz

student•

public class Album{
/**
	* <h1>Song</h1>
	*
	* Representa una canción de Spotify, con nombre, duracion y demas atributos
	*/
	public class Song{
		
		private String nombre;
		//...otros atributos
	}
	private ArrayList<Song> songs = new ArrayList();
	
	//..logica para clase albun.
}

Wilson Alejandro Gonzalez Gaitan

student•

Esta solucion no estarria cumpliendo con clases anidadas debido a que las canciones pueden entrar dentro de la clase principal

Kevin Manuel Wong

student•

public class Album{
		
		private class Song{
			private String nombre;
			private String artista;
		}
		private ArrayList<Song> canciones;
		private String nombreAlbum;
		
		public Album() {
		}
		public Album(ArrayList<Song> canciones, String nAlbum) {
			this.canciones = canciones;
			this.nombreAlbum = nAlbum;
		}
	}

Deyvis Neyser Valdez Gavilan

student•

public class Album {
	public class Song {
	}
}

Album album = new Album();
Album.Song song = album.new Song();

Carlos René Rodas Juarez

student•

public class Album{
	public static class Song{
	}
}

Carlos Daniel Boyanosky

student•

public class Album{
	private Song[] canciones;
	//Otros atributos
	public class Song{
		//Atributos de canciones
	}
}```

Jorge Jorge Marrero

student•

Esto no tiene mucha lógica para mi, porque yo puedo implementar la clase Autor que solo se va a utilizar en Song y no necesariamente tiene que estar anidada. La verdad sigo sin verle la utilidad a esta propiedad del lenguaje

Daniel Camacho

student•

public class Album {
	public static void main(String[] args) {
		
		Song song1 = new Song("SnarkyPuppy", "What About Me", "JazzFusion");
		Song song2 = new Song("DirtyLoops", "HitMe", "Pop Progressive");
		Song song3 = new Song("Jesus Molina", "Night in Tunisia", "Jazz");
		Song song4 = new Song("FourPLay", "Flying East", "Jazz Soul");
		Song song5 = new Song("Anthony Brancati", "Neo Funk", "Funk Soul");
		
		Set<Song> CollectionSongs = new HashSet<Song>();
		
		
		CollectionSong.add(song1);
		CollectionSong.add(song2);
		CollectionSong.add(song3);
		CollectionSong.add(song4);
		CollectionSong.add(song5);

		
	for (Song song : CollectionSongs) {
		System.out.println(song.getArtist() + song.getNameSong() + song.getGenre());
	}

	}
	
	public class Song{
		
	private String	artist;
	private String	nameSong;
	private String 	genre;
		
	public Song(String artist, String nameSong, String genre){
		this.artist = artist;
		this.nameSong = nameSong;
		this.genre = genre;
	
	}

	public String getArtist() {
		return artist;
	}

	public void setArtist(String artist) {
		this.artist = artist;
	}

	public String getNameSong() {
		return nameSong;
	}

	public void setNameSong(String nameSong) {
		this.nameSong = nameSong;
	}

	public String getGenre() {
		return genre;
	}

	public void setGenre(String genre) {
		this.genre = genre;
	}
	
	
	}
	}

Carlos Uriel de Jesus Sánchez González

student•

public class Album{

	private class Song{

	}

}

Josue Granados

student•

primero, la interface para el atributo audio de la clase song

public interface IPlayable {
	public void play();
}

la clase álbum y dentro la clase song. Dado que en spotify podemos buscar el álbum que queramos o buscar directamente la canción decidí hacer la clase Song no estática, ya que para encontrar una canción de un álbum debe existir dicho álbum.

public class Album {
	//the number of the song and the song
	public  HashMap <Integer,Song> songs;
	String artist;
	String name;
	short year;
	String recordsCompany;
	
	//constructor
	public Album(String artist, String name, short year, String recordsCompany) {
		super();
		this.artist = artist;
		this.name = name;
		this.year = year;
		this.recordsCompany = recordsCompany;
		songs = new HashMap <Integer,Song>();
		//this is for stablish the number of song in the album
		Scanner scanner = new Scanner(System.in);
		System.out.println("Number of songs for " + this.name);
		int numberOfSongs = scanner.nextInt();
		addSong(songs, numberOfSongs);
		
	}
	//Method to add songs to the list
	private void addSong(HashMap listSongs, int numberOfSongs) {
		
		for (int i = 0; i < numberOfSongs; i++) {
			this.songs.put(i + 1, new Song());
		}
		
	}
	
	//getters
	public String getArtist() {
		return artist;
	}

	public String getName() {
		return name;
	}

	public short getYear() {
		return year;
	}

	public String getRecordsCompany() {
		return recordsCompany;
	}
	//*********************Song inner class******************************
	public class Song {
		String name;
		String artist;
		short year;
		//atribute with an anonymous class
		IPlayable audio = new IPlayable() {
			@Override
			public void play() {
				System.out.println("lalalalalalalalalalalalalalalalalalalala");
			}
		};
		//construcutor
		public Song() {
			super();
			Scanner scanner = new Scanner(System.in);
			System.out.println("Name of the song: ");
			this.name = scanner.nextLine();
			System.out.println("Artist: ");
			this.artist = scanner.nextLine();
			System.out.println("Year of the song: ");
			this.year = scanner.nextShort();
		}
		//getters
		public String getName() {
			return name;
		}
		public String getArtist() {
			return artist;
		}
		public short getYear() {
			return year;
		}
	}

}

Andrés Felipe Hernández Ángel

student•

<code>
import java.util.ArrayList;
/**
 *
 * @author Hernandez
 */
public class Album {
    private int id;
    private ArrayList<Song> songs = new ArrayList();

    public int getId() {
        return id;
    }
  
    public ArrayList<Song> getSongs() {
        return songs;
    }

    public void setSongs(ArrayList<Song> songs) {
        this.songs = songs;
    }
    
    public class Song{
        private int id;
        private Album album;
        private double duration;

        public int getId() {
            return id;
        }

        public Album getAlbum() {
            return album;
        }

        public void setAlbum(Album album) {
            this.album = album;
        }

        public double getDuration() {
            return duration;
        }

        public void setDuration(double duration) {
            this.duration = duration;
        }
    }
}

Mario Jesús Arango Cupe

student•

//podria estar mejor, pero algo asi es mi idea

public class Album {

private ArrayList<Song> alSong;

public static class Song{

    private String album;
    private String nombre;
    private double duracion;

    public String getAlbum() {
        return album;
    }

    public void setAlbum(String album) {
        this.album = album;
    }

    public String getNombre() {
        return nombre;
    }

    public void setNombre(String nombre) {
        this.nombre = nombre;
    }

    public double getDuracion() {
        return duracion;
    }

    public void setDuracion(double duracion) {
        this.duracion = duracion;
    }
}

public ArrayList<Song> getAlSong() {
    return alSong;
}

public void setAlSong(ArrayList<Song> alSong) {
    this.alSong = alSong;
}


public void listar(){
    for (Song element:
         getAlSong()) {
        System.out.println(element.getAlbum());
        System.out.println(element.getNombre());
        System.out.println(element.getDuracion());
    }
}

} public class Main {

public static void main(String[] args) {


    Album.Song alAlbunSong = new Album.Song();
    alAlbunSong.setAlbum("NOMBRE DEL ALBUM");
    alAlbunSong.setNombre("NOMBRE DE LA CANCIÓN");
    alAlbunSong.setDuracion(3.25);

    ArrayList<Album.Song> alAS = new ArrayList<Album.Song>();
    alAS.add(alAlbunSong);

    Album listaAlbum = new Album();
    listaAlbum.setAlSong(alAS);

    listaAlbum.listar();


}

}

Jaime Pinto Abad

student•

import java.util.Date; import java.util.List;

public class Album {

private int codigo;
private String Nombre;
private  List<Song> objSongs;

public int getCodigo() {
    return codigo;
}

public void setCodigo(int codigo) {
    this.codigo = codigo;
}

public String getNombre() {
    return Nombre;
}

public void setNombre(String nombre) {
    Nombre = nombre;
}

public List<Song> getObjSongs() {
    return objSongs;
}

public void setObjSongs(List<Song> objSongs) {
    this.objSongs = objSongs;
}

public class Song{

    private int codigo;
    private String artista;
    private String duracion;
    private String genero;
    private Date  publicacion;

    public Song()
    {

    }

    public int getCodigo() {
        return codigo;
    }

    public void setCodigo(int codigo) {
        this.codigo = codigo;
    }

    public String getArtista() {
        return artista;
    }

    public void setArtista(String artista) {
        this.artista = artista;
    }

    public String getDuracion() {
        return duracion;
    }

    public void setDuracion(String duracion) {
        this.duracion = duracion;
    }

    public String getGenero() {
        return genero;
    }

    public void setGenero(String genero) {
        this.genero = genero;
    }

    public Date getPublicacion() {
        return publicacion;
    }

    public void setPublicacion(Date publicacion) {
        this.publicacion = publicacion;
    }



}

}

Laura Sofía Córdoba

student•

Clase Album

package logica;

import java.util.ArrayList;

public class Album {
	
	private int id;
	private ArrayList<Song> songs;
	
	public Album(int id) {
		this.id = id;
	}
		
	public int getId() {
		return id;
	}
	
	public void setId(int id) {
		this.id = id;
	}



	public ArrayList<Song> getSongs() {
		return songs;
	}

	public void setSongs(ArrayList<Song> songs) {
		this.songs = songs;
	}
	
	public static ArrayList<Album> makeAlbum(){
		ArrayList<Album>albums = new ArrayList<Album>();
		for(int i=1; i<=5; i++) {
			Album album = new Album(i);
			album.setSongs(Song.makeSong(album));
			albums.add(album);
			
		}
		return albums;
	}


	public static class Song {
		
		private int id;
		private Album album;
		
		public int getId() {
			return id;
		}
		public void setId(int id) {
			this.id = id;
		}
		public Album getAlbum() {
			return album;
		}
		public void setAlbum(Album album) {
			this.album = album;
		}
		
		public Song(int id, Album album) {
			this.id = id;
			this.setAlbum(album);
		}
		
		//creando songs 
		public static ArrayList <Song> makeSong(Album album){
			ArrayList<Song> songs = new ArrayList<Song>();
			for(int i =1; i<= 5; i++) {
				songs.add(new Song( i, album));
			}			
			return songs;
			
		}
		
	}

}

Clase Main

import java.util.ArrayList;

import logica.Album.Song;

public class Main {

	public static void main(String[] args) {
			
		ArrayList<Album> albums = Album.makeAlbum();
		ArrayList<Album.Song> songs;
				
		System.out.println("Album");
		for (Album album : albums) {
			System.out.println("album " + album.getId());
			//informacion song 
			songs = album.getSongs();
			for (Song song : songs) {
				System.out.println(song.getId());
			}			
		}
				
	}
}

Fernando Alberto Morales Reyes

student•

Así lo hice yo:

import java.util.ArrayList;

import java.util.List;

public class Album {

private String title;

private String artist;

private List<Song> songs;

public Album(String title, String artist) {

this.title = title;

this.artist = artist;

this.songs = new ArrayList<>();

}

// Método para agregar canciones al álbum

public void addSong(String songTitle, double duration) {

// Creamos la instancia de Song directamente desde el Album

Song newSong = new Song(songTitle, duration);

this.songs.add(newSong);

}

public void showTracklist() {

System.out.println("Album: " + title + " - " + artist);

for (Song s : songs) {

System.out.println("- " + s.getDetails());

}

// CLASE INTERNA (Inner Class)

// Solo existe y tiene sentido dentro de un Album

private class Song {

private String songTitle;

private double duration;

public Song(String songTitle, double duration) {

this.songTitle = songTitle;

this.duration = duration;

}

public String getDetails() {

return songTitle + " (" + duration + " min)";

}

Carlos Naveda

student•

El ejercicio lo resolví así:

De acuerdo al enuncionado tenemos dos cosas claras: 1) La clase Song tiene que ser anidada a Album 2) Solo la clase Album usará a Song, por lo cual tenemos que tener un método en Album que use los atributos de Song.

Cosas que yo deduje (quizá me equivoque pero es lo que entiendo) - La clase Song debe ser estática, ya que no necesitamos que Song sepa la instancia de Album, la relación es al revés, Album necesita saber las canciones que le pertenecen, por ello cree la Lista<Song> como atributo en Album. -La clase Song solo le puse getters, no setters ya las propiedades de una canción no se modifican en tiempo.

Mi código queda así

Daniela Mendez Camacho

student•

public class <u>Album</u> {

private List<Song> songs;

private String nombreAlbum;

public Album(String nombre) {

this.nombreAlbum = nombre;

this.songs = new ArrayList<>();

}

public void agregarCancion(String titulo, double duracion) {

Song nuevaCancion = new Song(titulo, duracion);

songs.add(nuevaCancion);

}

private class Song {

private String titulo;

private double duracion;

public Song(String titulo, double duracion) {

this.titulo = titulo;

this.duracion = duracion;

}

@Override

public String toString() {

return titulo + " (" + duracion + ")";

}

Pablo Villegas Palacio

student•

public class Principal {

public static void main(String[] args) {

Album album = new Album("Random Access Memories", "Daft Punk", 2013);

album.agregarCancion("Give Life Back to Music", 275);

album.agregarCancion("Get Lucky", 248);

album.agregarCancion("Instant Crush", 337);

System.out.println("Álbum: " + album);

System.out.println("Canciones:");

for (String nombre : album.listarCanciones()) {

System.out.println(" - " + nombre);

}

System.out.println("Duración total (s): " + album.duracionTotalSegundos());

album.eliminarCancionPorTitulo("Get Lucky");

System.out.println("\nTras eliminar 'Get Lucky':");

for (String nombre : album.listarCanciones()) {

System.out.println(" - " + nombre);

}

Alfredo Miguel Peña Martínez

student•

public class Album
{
    public class Song
    {
        
    }
}

Juan Carlos Reynoso Zuñiga

student•

public class Album {
	public class Song {
	}
}

Album album = new Album();
Album.Song song = album.new Song();

public class Album {

    private String name;
    private String author;
    private int year;
    private Song[] songs;

    public Album(String name, String author, int year) {
        this.name = name;
        this.author = author;
        this.year = year;
    }

    public void setAlbum(String[] names, int[] durations) {
        Song[] songs = new Song[names.length];
        for (int i = 0; i < names.length; i++) {
            songs[i] = new Song(names[i], durations[i]);
        }
        this.songs = songs;
    }

    private String getAlbum() {
        StringBuilder sb = new StringBuilder();
        for (Song song : songs) {
            sb.append(song);
        }
        return sb.toString();
    }

    public String toString() {
        return "\nALBUM: " + name +
                "\nAUTHOR: " + author +
                "\nYEAR: " + year +
                "\n\n::SONGS::\n" + getAlbum();
    }


    private static class Song {

        private String name;
        private int duration;

        private Song(String name, int duration) {
            this.name = name;
            this.duration = duration;
        }

        public String toString() {
            return "\nName: " + name +
                    "\nDuration: " + duration + " seconds\n";
        }
    }
}

    public static void main(String[] args) {
        String[] names = {"Uno", "Divenire", "Monday", "Andare", "Rose", "Primavera", "Oltremare", "L'origine Nascosta", "Fly", "Ascolta", "Ritornare", "Svanire"};
        int[] durations = {228, 402, 355, 422, 256, 444, 660, 192, 279, 289, 532, 449};
        Album album = new Album("Divenire","Ludovico Einaudi",2006);
        album.setAlbum(names, durations);
        System.out.println(album);
    }

public class Album{
/**
	* <h1>Song</h1>
	*
	* Representa una canción de Spotify, con nombre, duracion y demas atributos
	*/
	public class Song{
		
		private String nombre;
		//...otros atributos
	}
	private ArrayList<Song> songs = new ArrayList();
	
	//..logica para clase albun.
}

public class Album{
		
		private class Song{
			private String nombre;
			private String artista;
		}
		private ArrayList<Song> canciones;
		private String nombreAlbum;
		
		public Album() {
		}
		public Album(ArrayList<Song> canciones, String nAlbum) {
			this.canciones = canciones;
			this.nombreAlbum = nAlbum;
		}
	}

public class Album {
	public static void main(String[] args) {
		
		Song song1 = new Song("SnarkyPuppy", "What About Me", "JazzFusion");
		Song song2 = new Song("DirtyLoops", "HitMe", "Pop Progressive");
		Song song3 = new Song("Jesus Molina", "Night in Tunisia", "Jazz");
		Song song4 = new Song("FourPLay", "Flying East", "Jazz Soul");
		Song song5 = new Song("Anthony Brancati", "Neo Funk", "Funk Soul");
		
		Set<Song> CollectionSongs = new HashSet<Song>();
		
		
		CollectionSong.add(song1);
		CollectionSong.add(song2);
		CollectionSong.add(song3);
		CollectionSong.add(song4);
		CollectionSong.add(song5);

		
	for (Song song : CollectionSongs) {
		System.out.println(song.getArtist() + song.getNameSong() + song.getGenre());
	}

	}
	
	public class Song{
		
	private String	artist;
	private String	nameSong;
	private String 	genre;
		
	public Song(String artist, String nameSong, String genre){
		this.artist = artist;
		this.nameSong = nameSong;
		this.genre = genre;
	
	}

	public String getArtist() {
		return artist;
	}

	public void setArtist(String artist) {
		this.artist = artist;
	}

	public String getNameSong() {
		return nameSong;
	}

	public void setNameSong(String nameSong) {
		this.nameSong = nameSong;
	}

	public String getGenre() {
		return genre;
	}

	public void setGenre(String genre) {
		this.genre = genre;
	}
	
	
	}
	}

public class Album {
	//the number of the song and the song
	public  HashMap <Integer,Song> songs;
	String artist;
	String name;
	short year;
	String recordsCompany;
	
	//constructor
	public Album(String artist, String name, short year, String recordsCompany) {
		super();
		this.artist = artist;
		this.name = name;
		this.year = year;
		this.recordsCompany = recordsCompany;
		songs = new HashMap <Integer,Song>();
		//this is for stablish the number of song in the album
		Scanner scanner = new Scanner(System.in);
		System.out.println("Number of songs for " + this.name);
		int numberOfSongs = scanner.nextInt();
		addSong(songs, numberOfSongs);
		
	}
	//Method to add songs to the list
	private void addSong(HashMap listSongs, int numberOfSongs) {
		
		for (int i = 0; i < numberOfSongs; i++) {
			this.songs.put(i + 1, new Song());
		}
		
	}
	
	//getters
	public String getArtist() {
		return artist;
	}

	public String getName() {
		return name;
	}

	public short getYear() {
		return year;
	}

	public String getRecordsCompany() {
		return recordsCompany;
	}
	//*********************Song inner class******************************
	public class Song {
		String name;
		String artist;
		short year;
		//atribute with an anonymous class
		IPlayable audio = new IPlayable() {
			@Override
			public void play() {
				System.out.println("lalalalalalalalalalalalalalalalalalalala");
			}
		};
		//construcutor
		public Song() {
			super();
			Scanner scanner = new Scanner(System.in);
			System.out.println("Name of the song: ");
			this.name = scanner.nextLine();
			System.out.println("Artist: ");
			this.artist = scanner.nextLine();
			System.out.println("Year of the song: ");
			this.year = scanner.nextShort();
		}
		//getters
		public String getName() {
			return name;
		}
		public String getArtist() {
			return artist;
		}
		public short getYear() {
			return year;
		}
	}

}

<code>
import java.util.ArrayList;
/**
 *
 * @author Hernandez
 */
public class Album {
    private int id;
    private ArrayList<Song> songs = new ArrayList();

    public int getId() {
        return id;
    }
  
    public ArrayList<Song> getSongs() {
        return songs;
    }

    public void setSongs(ArrayList<Song> songs) {
        this.songs = songs;
    }
    
    public class Song{
        private int id;
        private Album album;
        private double duration;

        public int getId() {
            return id;
        }

        public Album getAlbum() {
            return album;
        }

        public void setAlbum(Album album) {
            this.album = album;
        }

        public double getDuration() {
            return duration;
        }

        public void setDuration(double duration) {
            this.duration = duration;
        }
    }
}

public class Album {

private ArrayList<Song> alSong;

public static class Song{

    private String album;
    private String nombre;
    private double duracion;

    public String getAlbum() {
        return album;
    }

    public void setAlbum(String album) {
        this.album = album;
    }

    public String getNombre() {
        return nombre;
    }

    public void setNombre(String nombre) {
        this.nombre = nombre;
    }

    public double getDuracion() {
        return duracion;
    }

    public void setDuracion(double duracion) {
        this.duracion = duracion;
    }
}

public ArrayList<Song> getAlSong() {
    return alSong;
}

public void setAlSong(ArrayList<Song> alSong) {
    this.alSong = alSong;
}


public void listar(){
    for (Song element:
         getAlSong()) {
        System.out.println(element.getAlbum());
        System.out.println(element.getNombre());
        System.out.println(element.getDuracion());
    }
}

public static void main(String[] args) {


    Album.Song alAlbunSong = new Album.Song();
    alAlbunSong.setAlbum("NOMBRE DEL ALBUM");
    alAlbunSong.setNombre("NOMBRE DE LA CANCIÓN");
    alAlbunSong.setDuracion(3.25);

    ArrayList<Album.Song> alAS = new ArrayList<Album.Song>();
    alAS.add(alAlbunSong);

    Album listaAlbum = new Album();
    listaAlbum.setAlSong(alAS);

    listaAlbum.listar();


}

private int codigo;
private String Nombre;
private  List<Song> objSongs;

public int getCodigo() {
    return codigo;
}

public void setCodigo(int codigo) {
    this.codigo = codigo;
}

public String getNombre() {
    return Nombre;
}

public void setNombre(String nombre) {
    Nombre = nombre;
}

public List<Song> getObjSongs() {
    return objSongs;
}

public void setObjSongs(List<Song> objSongs) {
    this.objSongs = objSongs;
}

public class Song{

    private int codigo;
    private String artista;
    private String duracion;
    private String genero;
    private Date  publicacion;

    public Song()
    {

    }

    public int getCodigo() {
        return codigo;
    }

    public void setCodigo(int codigo) {
        this.codigo = codigo;
    }

    public String getArtista() {
        return artista;
    }

    public void setArtista(String artista) {
        this.artista = artista;
    }

    public String getDuracion() {
        return duracion;
    }

    public void setDuracion(String duracion) {
        this.duracion = duracion;
    }

    public String getGenero() {
        return genero;
    }

    public void setGenero(String genero) {
        this.genero = genero;
    }

    public Date getPublicacion() {
        return publicacion;
    }

    public void setPublicacion(Date publicacion) {
        this.publicacion = publicacion;
    }



}

package logica;

import java.util.ArrayList;

public class Album {
	
	private int id;
	private ArrayList<Song> songs;
	
	public Album(int id) {
		this.id = id;
	}
		
	public int getId() {
		return id;
	}
	
	public void setId(int id) {
		this.id = id;
	}



	public ArrayList<Song> getSongs() {
		return songs;
	}

	public void setSongs(ArrayList<Song> songs) {
		this.songs = songs;
	}
	
	public static ArrayList<Album> makeAlbum(){
		ArrayList<Album>albums = new ArrayList<Album>();
		for(int i=1; i<=5; i++) {
			Album album = new Album(i);
			album.setSongs(Song.makeSong(album));
			albums.add(album);
			
		}
		return albums;
	}


	public static class Song {
		
		private int id;
		private Album album;
		
		public int getId() {
			return id;
		}
		public void setId(int id) {
			this.id = id;
		}
		public Album getAlbum() {
			return album;
		}
		public void setAlbum(Album album) {
			this.album = album;
		}
		
		public Song(int id, Album album) {
			this.id = id;
			this.setAlbum(album);
		}
		
		//creando songs 
		public static ArrayList <Song> makeSong(Album album){
			ArrayList<Song> songs = new ArrayList<Song>();
			for(int i =1; i<= 5; i++) {
				songs.add(new Song( i, album));
			}			
			return songs;
			
		}
		
	}

}

import java.util.ArrayList;

import logica.Album.Song;

public class Main {

	public static void main(String[] args) {
			
		ArrayList<Album> albums = Album.makeAlbum();
		ArrayList<Album.Song> songs;
				
		System.out.println("Album");
		for (Album album : albums) {
			System.out.println("album " + album.getId());
			//informacion song 
			songs = album.getSongs();
			for (Song song : songs) {
				System.out.println(song.getId());
			}			
		}
				
	}
}

Clase Song como clase interna en Album en Java

Introducción al Curso

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