music-streaming-service.md

Designing an Online Music Streaming Service Like Spotify

This article focuses on developing an object-oriented design for an Online Music Streaming Service similar to Spotify using Java.

The system aims to deliver a comprehensive music streaming experience.

System Requirements

The Online Music Streaming Service should:

1. User Account Management: Manage user registrations, profiles, and subscriptions.
2. Music Library Management: Maintain a library of songs, artists, and albums.
3. Streaming and Playback: Enable streaming of music and manage playback settings.
4. Playlist Management: Allow users to create and manage personalized playlists.
5. User Recommendation System: Offer music suggestions based on preferences and listening history.

Core Use Cases

1. Registering and Managing User Accounts
2. Browsing and Streaming Music
3. Creating and Editing Playlists
4. Recommending Music
5. Handling Subscriptions and Payments

UML/Class Diagrams

Key Classes:

• MusicStreamingService: Manages the system.
• User: Represents a subscriber.
• Song: Represents an individual music track.
• Playlist: Manages a collection of songs.
• Subscription: Handles subscription details.

Java Implementation

User Class

Manages user account information and preferences.

public class User {
    private String userId;
    private String name;
    private Subscription subscription;
    private List<Playlist> playlists;

    public User(String userId, String name) {
        this.userId = userId;
        this.name = name;
        this.playlists = new ArrayList<>();
        this.subscription = new Subscription();
    }

    public void createPlaylist(String playlistName) {
        Playlist newPlaylist = new Playlist(playlistName);
        playlists.add(newPlaylist);
    }

    // Getters and setters...
}```
### Song Class
Represents an individual music track.
```java
public class Song {
    private String songId;
    private String title;
    private String artist;
    private String album;
    private double duration;

    public Song(String songId, String title, String artist, String album, double duration) {
        this.songId = songId;
        this.title = title;
        this.artist = artist;
        this.album = album;
        this.duration = duration;
    }

    // Getters and setters...
}

Playlist Class

Manages a collection of songs.

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

public class Playlist {
    private String name;
    private List<Song> songs;

    public Playlist(String name) {
        this.name = name;
        this.songs = new ArrayList<>();
    }

    public void addSong(Song song) {
        songs.add(song);
    }

    // Getters and setters...
}

Subscription Class

Handles user subscription details.

public class Subscription {
    private SubscriptionType type;
    private double price;

    public Subscription() {
        this.type = SubscriptionType.FREE;
        this.price = 0.0;
    }

    public void upgradeSubscription(SubscriptionType newType) {
        this.type = newType;
        // Set price based on subscription type
    }

    // Getters and setters...
}

enum SubscriptionType {
    FREE, PREMIUM
}

MusicStreamingService Class

public class MusicStreamingService {
    private List<User> users;
    private List<Song> songs;

    public MusicStreamingService() {
        this.users = new ArrayList<>();
        this.songs = new ArrayList<>();
    }

    public void addUser(User user) {
        users.add(user);
    }

    public void addSong(Song song) {
        songs.add(song);
    }

    public List<Song> searchSongs(String title) {
        // Implement search logic to find songs by title
        List<Song> foundSongs = new ArrayList<>();
        for (Song song : songs) {
            if (song.getTitle().equalsIgnoreCase(title)) {
                foundSongs.add(song);
            }
        }
        return foundSongs;
    }

    public void subscribeUser(String userId, SubscriptionType subscriptionType) {
        User user = findUserById(userId);
        if (user != null) {
            user.getSubscription().upgradeSubscription(subscriptionType);
        }
    }

    private User findUserById(String userId) {
        for (User user : users) {
            if (user.getUserId().equals(userId)) {
                return user;
            }
        }
        return null;
    }

    // Other necessary methods...
}