I am creating two classes that are inherited from a class Item, CD and CD player. I have been able to create the CD and CD Player classes by using the "extends" keyword, but I do not know how to store several Strings in the field "features".

Here is what I need to add:

Change StockManager unit test class to perform the following additional tasks:
• add the following products
o A CD, id=110, name="Dr. Love’s Greatest Hits”, suggested retail price=17.95, Artist=”Dr. Love”, Record Label=”Artista”; tracks: “Hold on”, “Go away”, “Give some time”, “You bet – you loose”

o A CD, id=15, name=”Romance Music”, suggested retail price=15.98, Artist=”Various”, Record Label=”EMI”, tracks: ”Slow moves”, “Sweet Love”, “Serenity in time”

o A CD Player, id=32, name=”Philcosoft”, Manufacturer=”Zing Electronics”, price=155.56, features: “MP3”, “RW”, “Progressing Scan”
Now I know how to use the external method calls using dot notation, but I do not know how to add the "tracks" and "features" fields so that they store multiple Strings.

Here is my coding for the StockManager class:

Java Code:
import java.util.ArrayList;
/*
 * Class StockManager 
 * get info about the stock
 * A.K.
 * October 25, 2008
 */

public class StockManager 
{
    
    // list of products
     
    ArrayList<Product> list;
    
    /*
     * Constructor for objects of class StockManager
     * create new list of products
     */
    public StockManager()
    {
        list=new ArrayList<Product>();
    }
    
    /*
     * add product to the list
     */
    public void addProduct(Product p)
    {
        list.add(p);
    }
    /*
     * Print inventory info if its' quantity equals
     * to quantity
     * @param quantity
     */
    public void printInventoryExceptions(int quantity)
    {
        int i;
        int counter=0;
        for(i=0;i<list.size();i++)
            if(list.get(i).getQuantity()<=quantity)
            {
                counter++;
                System.out.println(list.get(i).getName());
                System.out.println(list.get(i).getQuantity());
            }
        if(counter==0)
            System.out.println("There aren't any product exceptions in the stock");
    }
    
    /*
     * find product with certain name and return it
     * @return product
     */
    private Product findProduct(String name)
    {
        int i;
    
        for(i=0;i<list.size();i++)
            if(list.get(i).getName().equalsIgnoreCase(name))
            {
                Product p=new Product(list.get(i).getID(),list.get(i).getName());
                return p;
            }
        return null;
        
    }
    /*
     * print product of certain name
     * @param name
     */
    public void printProduct(String name)
    {
        Product p=findProduct(name);
        System.out.println("There are "+p.getQuantity()+ " "+p.getName()+ " for product id "+p.getID());
        
    }

}
The CD Class:

Java Code:
/**
 * Write a description of class CD here.
 * 
 * @author (your name) 
 * @version (a version number or a date)
 */
public class CD extends Product
{
    // instance variables - replace the example below with your own
    private String artist;
    private String cdLabel;
    private int numberOfTracks;
    private double retailPrice;
    
    

    /**
     * Constructor for objects of class CD
     */
    public CD(int id, String title, String theArtist, String label, int tracks, double price)
    {
        // initialise instance variables
        super(id, title);
        cdLabel = label;
        artist = theArtist;
        numberOfTracks = tracks;
        retailPrice = price;
       
    }

    public String getArtist()
    {
        return artist;
    }

    public void changeArtist(String newArtist)
    {
        artist = newArtist;
    }
    
    public String getLabel()
    {
        return cdLabel;
    }
    
    public void changeLabel(String newCDLabel)
    {
        cdLabel = newCDLabel;
    }
    
    public int getNumberOfTracks()
    {
        return numberOfTracks;
    }
    
    public double getRetailPrice()
    {
        return retailPrice;
    }
    

}
The code for the CDPlayer class:

Java Code:
/**
 * Write a description of class CDPlayer here.
 * 
 * @author (your name) 
 * @version (a version number or a date)
 */
public class CDPlayer extends Product
{
    // instance variables - replace the example below with your own
    private String manufacturer;
    private String listOfFeatures;
    private double retailPrice;

    /**
     * Constructor for objects of class CDPlayer
     */
    public CDPlayer(int id, String title, String madeBy, String features, double price)
    {
        // initialise instance variables
        super(id, title);
        manufacturer = madeBy;
        listOfFeatures = features;
        retailPrice = price;
       
    }


}
Any help would be much appreciated!