Сколько ответственностей у Singleton

class DatabaseConnection {
    private static DatabaseConnection instance;
    
    private DatabaseConnection() {}
    
    public static DatabaseConnection getInstance() {
        if (instance == null) {
            instance = new DatabaseConnection();
        }
        return instance;
    }
    
    // Основная бизнес-логика
    public void connect() { /*...*/ }
}